Ecosystem Management (ecosystem + management)

Distribution by Scientific Domains


Selected Abstracts


INTEGRATING HUMANS IN ECOSYSTEM MANAGEMENT USING MULTI-CRITERIA DECISION MAKING,

JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 2 2003
Georgios E. Pavlikakis
ABSTRACT: The Ecosystem Management (EM) process belongs to the category of Multi-Criteria Decision Making (MCDM) problems. It requires appropriate decision support systems (DSS) where "all interested people" would be involved in the decision making process. Environmental values critical to EM, such as the biological diversity, health, productivity and sustainability, have to be studied, and play an important role in modeling the ecosystem functions; human values and preferences also influence decision making. Public participation in decision and policy making is one of the elements that differentiate EM from the traditional methods of management. Here, a methodology is presented on how to quantify human preferences in EM decision making. The case study of the National Park of River Nestos Delta and Lakes Vistonida and Ismarida in Greece, presented as an application of this methodology, shows that the direct involvement of the public, the quantification of its preferences and the decision maker's attitude provide a strong tool to the EM decision making process. Public preferences have been given certain weights and three MCDM methods, namely, the Expected Utility Method, Compromise Programming and the Analytic Hierarchy Process, have been used to select alternative management solutions that lead to the best configuration of the ecosystem and are also socially acceptable. [source]


Obstacles to Bottom-Up Implementation of Marine Ecosystem Management

CONSERVATION BIOLOGY, Issue 5 2008
KIRSTEN E. EVANS
manejo de ecosistemas; manejo marino basado en ecosistemas; participación de partes interesadas; planificación de la conservación Abstract:,Ecosystem management (EM) offers a means to address multiple threats to marine resources. Despite recognition of the importance of stakeholder involvement, most efforts to implement EM in marine systems are the product of top-down regulatory control. We describe a rare, stakeholder-driven attempt to implement EM from the bottom up in San Juan County, Washington (U.S.A.). A citizens advisory group led a 2-year, highly participatory effort to develop an ecosystem-based management plan, guided by a preexisting conservation-planning framework. A key innovation was to incorporate social dimensions by designating both sociocultural and biodiversity targets in the planning process. Multiple obstacles hindered implementation of EM in this setting. Despite using a surrogate scheme, the information-related transaction costs of planning were substantial: information deficits prevented assessment of some biodiversity targets and insufficient resources combined with information deficits prevented scientific assessment of the sociocultural targets. Substantial uncertainty, practical constraints to stakeholder involvement, and the existence of multiple, potentially conflicting, objectives increased negotiation-related costs. Although information deficits and uncertainty, coupled with underinvestment in the transaction costs of planning, could reduce the long-term effectiveness of the plan itself, the social capital and momentum developed through the planning process could yield unforeseeable future gains in protection of marine resources. The obstacles we identified here will require early and sustained attention in efforts to implement ecosystem management in other grassroots settings. Resumen:,El manejo de ecosistemas es un medio para abordar múltiples amenazas a los recursos marinos. No obstante el reconocimiento de la importancia de la participación de las partes interesadas, la mayoría de los esfuerzos para implementar el manejo de ecosistemas en sistemas marinos son producto del control normativo de arriba hacia abajo. Describimos un intento raro, conducido por las partes interesadas, por implementar el manejo del ecosistema de abajo hacia arriba en el Condado San Juan, Washington (E.U.A.). Un grupo consultivo de ciudadanos dirigió un esfuerzo altamente participativo para desarrollar un plan de manejo basado en el ecosistema, guiados por un marco de planificación de la conservación preexistente. Una innovación clave fue la incorporación de dimensiones sociales al incluir objetivos tanto socioculturales como de biodiversidad en el proceso de planificación. Múltiples obstáculos dificultaron la implementación del manejo del ecosistema en este escenario. No obstante que se utilizó un plan sustituto, los costos de transacción de la planificación relacionados con la información fueron mayores de lo que el grupo pudo superar: los déficits de información impidieron la evaluación de algunos objetivos de biodiversidad y la insuficiencia de recursos combinada con los déficits de información impidieron la evaluación científica de los objetivos socioculturales. Los costos relacionados con la negociación incrementaron por la incertidumbre, por limitaciones prácticas en la participación de partes interesadas y la existencia de objetivos múltiples, potencialmente conflictivos. Aunque los déficits de información y la incertidumbre, aunados con la baja inversión en los costos de transacción de la planificación, pudieran reducir la efectividad a largo plazo del plan mismo, el capital social y el ímpetu desarrollados durante el proceso de planificación podrían producir ganancias futuras imprevisibles para la protección de recursos marinos. Los obstáculos que identificamos aquí requerirán de atención temprana y sostenida en los esfuerzos para implementar el manejo de ecosistemas en otros escenarios de base popular. [source]


Achieving Integrative, Collaborative Ecosystem Management

CONSERVATION BIOLOGY, Issue 5 2006
HEATHER L. KEOUGH
beneficios sociales y ecológicos; gestión; participación pública; toma de decisiones cooperativa Abstract:,Although numerous principles have been identified as being important for successfully integrating social and ecological factors in collaborative management, few authors have illustrated how these principles are used and why they are effective. On the basis of a review of the ecosystem management and collaboration literature, we identified eight factors important for integrative, collaborative ecosystem management,integrated and balanced goals, inclusive public involvement, stakeholder influence, consensus group approach, collaborative stewardship, monitoring and adaptive management, multidisciplinary data, and economic incentives. We examined four cases of successful ecosystem management to illustrate how the factors were incorporated and discuss the role they played in each case's success. The cases illustrate that balancing social and ecosystem sustainability goals is possible. Collaborative efforts resulted in part from factors aimed at making plans economically feasible and from meaningful stakeholder participation in ongoing management. It also required participation in monitoring programs to ensure stakeholder interests were protected and management efforts were focused on agreed-upon goals. Data collection efforts were not all-inclusive and systematic; rather, they addressed the ecological, economic, and social aspects of key issues as they emerged over time. Economic considerations appear to be broader than simply providing economic incentives; stakeholders seem willing to trade some economic value for recreational or environmental benefits. The cases demonstrate that it is not idealistic to believe integrative, collaborative ecosystem management is possible in field applications. Resumen:,Aunque numerosos principios han sido identificados como importantes para la integración exitosa de factores sociales y ecológicos en la gestión cooperativa, pocos autores han ilustrado como son utilizados estos principios y porque son efectivos. Con base en una revisión de la literatura sobre gestión de ecosistemas y colaboración, identificamos cinco factores,metas integradas y balanceadas, inclusive participación pública, influencia de grupos de interés, estrategia de consenso en el grupo, gestión cooperativa, gestión adaptativa y monitoreo, datos multidisciplinarios e incentivos económicos,que son importantes para la gestión integradora y cooperativa de ecosistemas. Examinamos cuatro casos de gestión exitosa de ecosistemas para ilustrar como fueron incorporados los factores y discutimos el papel que jugaron en el éxito de cada caso. Los casos ilustran que el balance de metas de sustentabilidad social y ecológica es posible. En parte, los esfuerzos cooperativos resultaron de factores orientados a hacer que los planes fueran económicamente viables y de la participación significativa de grupos de interés en la gestión en curso. También se requirió la participación en programas de monitoreo para asegurar que los intereses de los grupos fueran protegidos y los esfuerzos de gestión se enfocaran en las metas acordadas. No todos los esfuerzos de recolecta de datos fueron incluyentes y sistemáticos, más bien, eran dirigidos a los aspectos ecológicos, económicos y sociales de temas clave a medida que emergían. Las consideraciones económicas parecen ser más amplias que simplemente proporcionar incentivos económicos, los grupos de interés parecen dispuestos a cambiar algo de valor económico por beneficios recreativos o ambientales. Los casos demuestran que no es idealista pensar que es posible aplicar la gestión integradora y cooperativa de ecosistemas en el campo. [source]


The Northwest Forest Plan as a Model for Broad-Scale Ecosystem Management: a Social Perspective

CONSERVATION BIOLOGY, Issue 2 2006
SUSAN CHARNLEY
conservación y desarrollo; comunidades rurales; gestión forestal; monitoreo socioeconómico Abstract:,I evaluated the Northwest Forest Plan as a model for ecosystem management to achieve social and economic goals in communities located around federal forests in the U.S. Pacific Northwest. My assessment is based on the results of socioeconomic monitoring conducted to evaluate progress in achieving the plan's goals during its first 10 years. The assessment criteria I used related to economic development and social justice. The Northwest Forest Plan incorporated economic development and social justice goals in its design. Socioeconomic monitoring results indicate that plan implementation to achieve those goals met with mixed success, however. I hypothesize there are two important reasons the plan's socioeconomic goals were not fully met: some of the key assumptions underlying the implementation strategies were flawed and agency institutional capacity to achieve the goals was limited. To improve broad-scale ecosystem management in the future, decision makers should ensure that natural-resource management policies are socially acceptable; land-management agencies have the institutional capacity to achieve their management goals; and social and economic management goals (and the strategies for implementing them) are based on accurate assumptions about the relations between the resources being managed and well-being in local communities. One of the difficulties of incorporating economic development and social justice goals in conservation initiatives is finding ways to link conservation behavior and development activities. From a social perspective, the Northwest Forest Plan as a model for ecosystem management is perhaps most valuable in its attempt to link the biophysical and socioeconomic goals of forest management by creating high-quality jobs for residents of forest communities in forest stewardship and ecosystem management work, thereby contributing to conservation. Resumen:,Evalué el Plan Forestal del Noroeste como un modelo para la gestión de ecosistemas para alcanzar metas sociales y económicas en comunidades localizadas alrededor de bosques federales en el Pacífico Noroeste de E.U.A. Mi evaluación se basa en los resultados del monitoreo socioeconómico desarrollado para evaluar el progreso en el logro de las metas del plan durantes sus 10 primeros años. Los criterios de evaluación que utilicé se relacionan con el desarrollo económico y la justicia social. El diseño del Plan Forestal del Noroeste incorporó metas de desarrollo económico y de justicia social. Sin embargo, los resultados del monitoreo socioeconómico indican que éxito en la implementación del plan para alcanzar esas metas fue combinado. Postulé la hipótesis de que hay dos razones importantes por las que las metas socioeconómicas del plan no se cumplieron totalmente: algunas de las suposiciones clave en las estrategias de implementación fueron deficientes y la capacidad institucional de la agencia para alcanzar las metas era limitada. Para mejorar la gestión de ecosistemas a gran escala en el futuro, los tomadores de decisiones deberán asegurarse que las políticas de gestión de recursos naturales sean aceptables socialmente; que las agencias de gestión de tierras tengan la capacidad institucional para cumplir sus metas de gestión; y que las metas de gestión sociales y económicas (y las estrategias para su implementación) se basen en suposiciones precisas de las relaciones entre los recursos a gestionar y el bienestar de las comunidades locales. La manera de vincular comportamiento de conservación y actividades de desarrollo es una de las dificultades para la incorporación de metas de desarrollo económico y de justicia social en las iniciativas de conservación. Desde una perspectiva social, el Plan Forestal del Noroeste como modelo para la gestión de ecosistemas quizás es más valioso por su intento de vincular las metas biofísicas y socioeconómicas de la gestión forestal mediante la creación de empleos de alta calidad para residentes de las comunidades en labores de regulación y supervisión forestal y de gestión de ecosistemas, por lo tanto contribuye a la conservación. [source]


Obstacles to Bottom-Up Implementation of Marine Ecosystem Management

CONSERVATION BIOLOGY, Issue 5 2008
KIRSTEN E. EVANS
manejo de ecosistemas; manejo marino basado en ecosistemas; participación de partes interesadas; planificación de la conservación Abstract:,Ecosystem management (EM) offers a means to address multiple threats to marine resources. Despite recognition of the importance of stakeholder involvement, most efforts to implement EM in marine systems are the product of top-down regulatory control. We describe a rare, stakeholder-driven attempt to implement EM from the bottom up in San Juan County, Washington (U.S.A.). A citizens advisory group led a 2-year, highly participatory effort to develop an ecosystem-based management plan, guided by a preexisting conservation-planning framework. A key innovation was to incorporate social dimensions by designating both sociocultural and biodiversity targets in the planning process. Multiple obstacles hindered implementation of EM in this setting. Despite using a surrogate scheme, the information-related transaction costs of planning were substantial: information deficits prevented assessment of some biodiversity targets and insufficient resources combined with information deficits prevented scientific assessment of the sociocultural targets. Substantial uncertainty, practical constraints to stakeholder involvement, and the existence of multiple, potentially conflicting, objectives increased negotiation-related costs. Although information deficits and uncertainty, coupled with underinvestment in the transaction costs of planning, could reduce the long-term effectiveness of the plan itself, the social capital and momentum developed through the planning process could yield unforeseeable future gains in protection of marine resources. The obstacles we identified here will require early and sustained attention in efforts to implement ecosystem management in other grassroots settings. Resumen:,El manejo de ecosistemas es un medio para abordar múltiples amenazas a los recursos marinos. No obstante el reconocimiento de la importancia de la participación de las partes interesadas, la mayoría de los esfuerzos para implementar el manejo de ecosistemas en sistemas marinos son producto del control normativo de arriba hacia abajo. Describimos un intento raro, conducido por las partes interesadas, por implementar el manejo del ecosistema de abajo hacia arriba en el Condado San Juan, Washington (E.U.A.). Un grupo consultivo de ciudadanos dirigió un esfuerzo altamente participativo para desarrollar un plan de manejo basado en el ecosistema, guiados por un marco de planificación de la conservación preexistente. Una innovación clave fue la incorporación de dimensiones sociales al incluir objetivos tanto socioculturales como de biodiversidad en el proceso de planificación. Múltiples obstáculos dificultaron la implementación del manejo del ecosistema en este escenario. No obstante que se utilizó un plan sustituto, los costos de transacción de la planificación relacionados con la información fueron mayores de lo que el grupo pudo superar: los déficits de información impidieron la evaluación de algunos objetivos de biodiversidad y la insuficiencia de recursos combinada con los déficits de información impidieron la evaluación científica de los objetivos socioculturales. Los costos relacionados con la negociación incrementaron por la incertidumbre, por limitaciones prácticas en la participación de partes interesadas y la existencia de objetivos múltiples, potencialmente conflictivos. Aunque los déficits de información y la incertidumbre, aunados con la baja inversión en los costos de transacción de la planificación, pudieran reducir la efectividad a largo plazo del plan mismo, el capital social y el ímpetu desarrollados durante el proceso de planificación podrían producir ganancias futuras imprevisibles para la protección de recursos marinos. Los obstáculos que identificamos aquí requerirán de atención temprana y sostenida en los esfuerzos para implementar el manejo de ecosistemas en otros escenarios de base popular. [source]


The importance of ecological research for ecosystem management: The case of browsing by swamp wallabies (Wallabia bicolor) in commercially harvested native forests

ECOLOGICAL MANAGEMENT & RESTORATION, Issue 1 2004
Julian Di Stefano
Summary Ecosystem management often proceeds within the context of sub-optimal relationships between ecologists and ecosystem managers, and management outcomes could be improved with greater collaboration between members of these disciplines. This paper identifies an ecosystem management problem resulting from the interaction between timber harvesting and browsing wallabies, and this case study is used to exemplify how ecological data and expertise can contribute to the process of ecosystem management. It is argued that appropriate use of existing ecological data, establishment of strategic new research and the implementation of management actions as experimental hypothesis tests can facilitate achievement of management objectives, but greater collaboration between ecologists and managers is required before this can occur. Reasons for sub-optimal relationships are outlined, and the potential for structural change within large State-run ecosystem management agencies to improve interactions between managers and ecologists is discussed. [source]


Obstacles to Bottom-Up Implementation of Marine Ecosystem Management

CONSERVATION BIOLOGY, Issue 5 2008
KIRSTEN E. EVANS
manejo de ecosistemas; manejo marino basado en ecosistemas; participación de partes interesadas; planificación de la conservación Abstract:,Ecosystem management (EM) offers a means to address multiple threats to marine resources. Despite recognition of the importance of stakeholder involvement, most efforts to implement EM in marine systems are the product of top-down regulatory control. We describe a rare, stakeholder-driven attempt to implement EM from the bottom up in San Juan County, Washington (U.S.A.). A citizens advisory group led a 2-year, highly participatory effort to develop an ecosystem-based management plan, guided by a preexisting conservation-planning framework. A key innovation was to incorporate social dimensions by designating both sociocultural and biodiversity targets in the planning process. Multiple obstacles hindered implementation of EM in this setting. Despite using a surrogate scheme, the information-related transaction costs of planning were substantial: information deficits prevented assessment of some biodiversity targets and insufficient resources combined with information deficits prevented scientific assessment of the sociocultural targets. Substantial uncertainty, practical constraints to stakeholder involvement, and the existence of multiple, potentially conflicting, objectives increased negotiation-related costs. Although information deficits and uncertainty, coupled with underinvestment in the transaction costs of planning, could reduce the long-term effectiveness of the plan itself, the social capital and momentum developed through the planning process could yield unforeseeable future gains in protection of marine resources. The obstacles we identified here will require early and sustained attention in efforts to implement ecosystem management in other grassroots settings. Resumen:,El manejo de ecosistemas es un medio para abordar múltiples amenazas a los recursos marinos. No obstante el reconocimiento de la importancia de la participación de las partes interesadas, la mayoría de los esfuerzos para implementar el manejo de ecosistemas en sistemas marinos son producto del control normativo de arriba hacia abajo. Describimos un intento raro, conducido por las partes interesadas, por implementar el manejo del ecosistema de abajo hacia arriba en el Condado San Juan, Washington (E.U.A.). Un grupo consultivo de ciudadanos dirigió un esfuerzo altamente participativo para desarrollar un plan de manejo basado en el ecosistema, guiados por un marco de planificación de la conservación preexistente. Una innovación clave fue la incorporación de dimensiones sociales al incluir objetivos tanto socioculturales como de biodiversidad en el proceso de planificación. Múltiples obstáculos dificultaron la implementación del manejo del ecosistema en este escenario. No obstante que se utilizó un plan sustituto, los costos de transacción de la planificación relacionados con la información fueron mayores de lo que el grupo pudo superar: los déficits de información impidieron la evaluación de algunos objetivos de biodiversidad y la insuficiencia de recursos combinada con los déficits de información impidieron la evaluación científica de los objetivos socioculturales. Los costos relacionados con la negociación incrementaron por la incertidumbre, por limitaciones prácticas en la participación de partes interesadas y la existencia de objetivos múltiples, potencialmente conflictivos. Aunque los déficits de información y la incertidumbre, aunados con la baja inversión en los costos de transacción de la planificación, pudieran reducir la efectividad a largo plazo del plan mismo, el capital social y el ímpetu desarrollados durante el proceso de planificación podrían producir ganancias futuras imprevisibles para la protección de recursos marinos. Los obstáculos que identificamos aquí requerirán de atención temprana y sostenida en los esfuerzos para implementar el manejo de ecosistemas en otros escenarios de base popular. [source]


Consumer Control of Salt Marshes Driven by Human Disturbance

CONSERVATION BIOLOGY, Issue 3 2008
MARK D. BERTNESS
control de consumidor; impactos humanos; conservación de pantano de sal; cascadas de trophic Abstract:,Salt marsh ecosystems are widely considered to be controlled exclusively by bottom,up forces, but there is mounting evidence that human disturbances are triggering consumer control in western Atlantic salt marshes, often with catastrophic consequences. In other marine ecosystems, human disturbances routinely dampen (e.g., coral reefs, sea grass beds) and strengthen (e.g., kelps) consumer control, but current marsh theory predicts little potential interaction between humans and marsh consumers. Thus, human modification of top,down control in salt marshes was not anticipated and was even discounted in current marsh theory, despite loud warnings about the potential for cascading human impacts from work in other marine ecosystems. In spite of recent experiments that have challenged established marsh dogma and demonstrated consumer-driven die-off of salt marsh ecosystems, government agencies and nongovernmental organizations continue to manage marsh die-offs under the old theoretical framework and only consider bottom,up forces as causal agents. This intellectual dependency of many coastal ecologists and managers on system-specific theory (i.e., marsh bottom,up theory) has the potential to have grave repercussions for coastal ecosystem management and conservation in the face of increasing human threats. We stress that marine vascular plant communities (salt marshes, sea grass beds, mangroves) are likely more vulnerable to runaway grazing and consumer-driven collapse than is currently recognized by theory, particularly in low-diversity ecosystems like Atlantic salt marshes. Resumen:,Se ha considerado extensamente que los ecosistemas de marismas son controlados exclusivamente por dinámicas abajo-arriba, pero se ha acumulado evidencia de que las perturbaciones humanas están provocando el control por consumidores en marismas del Atlántico occidental, a menudo con consecuencias catastróficas. En otros ecosistemas marinos, las perturbaciones humanas rutinariamente disminuyen (e.g., arrecifes de coral, pastos marinos) y refuerzan (e.g., varec) el control por consumidores, pero la teoría de marismas actual predice una leve interacción potencial entre humanos y consumidores en las marismas. Por lo tanto, las modificaciones humanas al control arriba-abajo en las marismas no estaba anticipada y aun era descontada en la teoría de marismas actual, a pesar de advertencias sobre el potencial de impactos humanos en cascada en trabajos en otros ecosistemas marinos. No obstante los experimentos recientes que han desafiado el dogma de marismas establecido y que han demostrado la desaparición gradual de marismas conducida por consumidores, las agencias gubernamentales y las organizaciones no gubernamentales continúan manejando la disminución de marismas en el marco de la teoría vieja y sólo consideran como agentes causales a factores abajo-arriba. Esta dependencia intelectual en la teoría sistema-específico (i.e., teoría de marismas abajo-arriba) de muchos ecólogos y manejadores costeros tiene el potencial de tener repercusiones graves para el manejo y conservación de ecosistemas costeros frente a las crecientes amenazas humanas. Enfatizamos que las comunidades plantas vasculares marinas (marismas, pastos marinos, manglares) son potencialmente más vulnerables al pastoreo descontrolado y al colapso conducido por consumidores que lo que reconoce la teoría actualmente, particularmente en ecosistemas con baja diversidad como las marismas del Atlántico. [source]


Achieving Integrative, Collaborative Ecosystem Management

CONSERVATION BIOLOGY, Issue 5 2006
HEATHER L. KEOUGH
beneficios sociales y ecológicos; gestión; participación pública; toma de decisiones cooperativa Abstract:,Although numerous principles have been identified as being important for successfully integrating social and ecological factors in collaborative management, few authors have illustrated how these principles are used and why they are effective. On the basis of a review of the ecosystem management and collaboration literature, we identified eight factors important for integrative, collaborative ecosystem management,integrated and balanced goals, inclusive public involvement, stakeholder influence, consensus group approach, collaborative stewardship, monitoring and adaptive management, multidisciplinary data, and economic incentives. We examined four cases of successful ecosystem management to illustrate how the factors were incorporated and discuss the role they played in each case's success. The cases illustrate that balancing social and ecosystem sustainability goals is possible. Collaborative efforts resulted in part from factors aimed at making plans economically feasible and from meaningful stakeholder participation in ongoing management. It also required participation in monitoring programs to ensure stakeholder interests were protected and management efforts were focused on agreed-upon goals. Data collection efforts were not all-inclusive and systematic; rather, they addressed the ecological, economic, and social aspects of key issues as they emerged over time. Economic considerations appear to be broader than simply providing economic incentives; stakeholders seem willing to trade some economic value for recreational or environmental benefits. The cases demonstrate that it is not idealistic to believe integrative, collaborative ecosystem management is possible in field applications. Resumen:,Aunque numerosos principios han sido identificados como importantes para la integración exitosa de factores sociales y ecológicos en la gestión cooperativa, pocos autores han ilustrado como son utilizados estos principios y porque son efectivos. Con base en una revisión de la literatura sobre gestión de ecosistemas y colaboración, identificamos cinco factores,metas integradas y balanceadas, inclusive participación pública, influencia de grupos de interés, estrategia de consenso en el grupo, gestión cooperativa, gestión adaptativa y monitoreo, datos multidisciplinarios e incentivos económicos,que son importantes para la gestión integradora y cooperativa de ecosistemas. Examinamos cuatro casos de gestión exitosa de ecosistemas para ilustrar como fueron incorporados los factores y discutimos el papel que jugaron en el éxito de cada caso. Los casos ilustran que el balance de metas de sustentabilidad social y ecológica es posible. En parte, los esfuerzos cooperativos resultaron de factores orientados a hacer que los planes fueran económicamente viables y de la participación significativa de grupos de interés en la gestión en curso. También se requirió la participación en programas de monitoreo para asegurar que los intereses de los grupos fueran protegidos y los esfuerzos de gestión se enfocaran en las metas acordadas. No todos los esfuerzos de recolecta de datos fueron incluyentes y sistemáticos, más bien, eran dirigidos a los aspectos ecológicos, económicos y sociales de temas clave a medida que emergían. Las consideraciones económicas parecen ser más amplias que simplemente proporcionar incentivos económicos, los grupos de interés parecen dispuestos a cambiar algo de valor económico por beneficios recreativos o ambientales. Los casos demuestran que no es idealista pensar que es posible aplicar la gestión integradora y cooperativa de ecosistemas en el campo. [source]


The Northwest Forest Plan as a Model for Broad-Scale Ecosystem Management: a Social Perspective

CONSERVATION BIOLOGY, Issue 2 2006
SUSAN CHARNLEY
conservación y desarrollo; comunidades rurales; gestión forestal; monitoreo socioeconómico Abstract:,I evaluated the Northwest Forest Plan as a model for ecosystem management to achieve social and economic goals in communities located around federal forests in the U.S. Pacific Northwest. My assessment is based on the results of socioeconomic monitoring conducted to evaluate progress in achieving the plan's goals during its first 10 years. The assessment criteria I used related to economic development and social justice. The Northwest Forest Plan incorporated economic development and social justice goals in its design. Socioeconomic monitoring results indicate that plan implementation to achieve those goals met with mixed success, however. I hypothesize there are two important reasons the plan's socioeconomic goals were not fully met: some of the key assumptions underlying the implementation strategies were flawed and agency institutional capacity to achieve the goals was limited. To improve broad-scale ecosystem management in the future, decision makers should ensure that natural-resource management policies are socially acceptable; land-management agencies have the institutional capacity to achieve their management goals; and social and economic management goals (and the strategies for implementing them) are based on accurate assumptions about the relations between the resources being managed and well-being in local communities. One of the difficulties of incorporating economic development and social justice goals in conservation initiatives is finding ways to link conservation behavior and development activities. From a social perspective, the Northwest Forest Plan as a model for ecosystem management is perhaps most valuable in its attempt to link the biophysical and socioeconomic goals of forest management by creating high-quality jobs for residents of forest communities in forest stewardship and ecosystem management work, thereby contributing to conservation. Resumen:,Evalué el Plan Forestal del Noroeste como un modelo para la gestión de ecosistemas para alcanzar metas sociales y económicas en comunidades localizadas alrededor de bosques federales en el Pacífico Noroeste de E.U.A. Mi evaluación se basa en los resultados del monitoreo socioeconómico desarrollado para evaluar el progreso en el logro de las metas del plan durantes sus 10 primeros años. Los criterios de evaluación que utilicé se relacionan con el desarrollo económico y la justicia social. El diseño del Plan Forestal del Noroeste incorporó metas de desarrollo económico y de justicia social. Sin embargo, los resultados del monitoreo socioeconómico indican que éxito en la implementación del plan para alcanzar esas metas fue combinado. Postulé la hipótesis de que hay dos razones importantes por las que las metas socioeconómicas del plan no se cumplieron totalmente: algunas de las suposiciones clave en las estrategias de implementación fueron deficientes y la capacidad institucional de la agencia para alcanzar las metas era limitada. Para mejorar la gestión de ecosistemas a gran escala en el futuro, los tomadores de decisiones deberán asegurarse que las políticas de gestión de recursos naturales sean aceptables socialmente; que las agencias de gestión de tierras tengan la capacidad institucional para cumplir sus metas de gestión; y que las metas de gestión sociales y económicas (y las estrategias para su implementación) se basen en suposiciones precisas de las relaciones entre los recursos a gestionar y el bienestar de las comunidades locales. La manera de vincular comportamiento de conservación y actividades de desarrollo es una de las dificultades para la incorporación de metas de desarrollo económico y de justicia social en las iniciativas de conservación. Desde una perspectiva social, el Plan Forestal del Noroeste como modelo para la gestión de ecosistemas quizás es más valioso por su intento de vincular las metas biofísicas y socioeconómicas de la gestión forestal mediante la creación de empleos de alta calidad para residentes de las comunidades en labores de regulación y supervisión forestal y de gestión de ecosistemas, por lo tanto contribuye a la conservación. [source]


Examining the role of the forest industry in collaborative ecosystem management: implications for corporate strategy

CORPORATE SOCIAL RESPONSIBILITY AND ENVIRONMENTAL MANAGEMENT, Issue 1 2005
Jennifer Dyke
Abstract The North American timber industry owns or controls a substantial amount of commercial timberland, and it is within this privately held acreage that major portions of critical natural habitat and areas of biodiversity are found. Because significant ecosystem components and processes lie within the ownership of forestry operations, industry participation in collaborative ecosystem management initiatives is vital to protect the integrity of ecological units at the landscape scale. This article analyzes and identifies the role of industry in ecosystem management projects, industry's willingness to participate in collaborative ecosystem management and the motivations behind company participation. Companies indicated active involvement in collaborative ecosystem management as both project initiators and collaborators. Motivations for participating in collaborative ecosystem management initiatives include the desires to decrease governmental regulations, collect data, develop relationships and improve current practices. Many companies also feel that participation is financially beneficial because it positively impacts corporate public relations. We discuss the implications of these results for developing an effective corporate environmental strategy associated with resource-based industries. Copyright © 2005 John Wiley & Sons, Ltd and ERP Environment. [source]


Implications of Liebig's law of the minimum for the use of ecological indicators based on abundance

ECOGRAPHY, Issue 2 2005
J. G. Hiddink
Many ecological responses to environmental variables or anthropogenic agents are difficult and expensive to measure. Therefore it is attractive to describe such responses in terms of indicators that are easier to measure. In ecosystem management, indicators can be used to monitor spatial and temporal changes in an environmental feature. The aim of this paper is to show that it is important to take Liebig's law of the minimum into consideration to understand when it is appropriate or inappropriate to use ecological indicators based on abundance. When developing indicators that relate the abundance of an organism to an environmental factor, it is likely that this relationship will be polygonal rather than a simple linear relationship. The upper boundary of the distribution describes how abundance is limited by this factor, while the variation below the upper boundary is explained by situations when factors other than the factor of interest limit abundance. The variation below the upper boundary of the distribution means that the use of indicators to examine spatial patterns in the response of abundance to an environmental factor can be problematic. Thus, while abundance-based indicators can identify sites that are in a good condition, they are less useful to detect those affected by environmental degradation. In contrast, abundance-based ecological indicators may enable temporal monitoring of the impact of environmental factors, as it is expected that limiting factors are less variable in time than in space. In conclusion, when multiple factors are limiting, a significant correlation between an indicator and a variable is not enough to validate the status of a factor as an indicator. [source]


The importance of ecological research for ecosystem management: The case of browsing by swamp wallabies (Wallabia bicolor) in commercially harvested native forests

ECOLOGICAL MANAGEMENT & RESTORATION, Issue 1 2004
Julian Di Stefano
Summary Ecosystem management often proceeds within the context of sub-optimal relationships between ecologists and ecosystem managers, and management outcomes could be improved with greater collaboration between members of these disciplines. This paper identifies an ecosystem management problem resulting from the interaction between timber harvesting and browsing wallabies, and this case study is used to exemplify how ecological data and expertise can contribute to the process of ecosystem management. It is argued that appropriate use of existing ecological data, establishment of strategic new research and the implementation of management actions as experimental hypothesis tests can facilitate achievement of management objectives, but greater collaboration between ecologists and managers is required before this can occur. Reasons for sub-optimal relationships are outlined, and the potential for structural change within large State-run ecosystem management agencies to improve interactions between managers and ecologists is discussed. [source]


The relationship between fishing methods, fisheries management and the estimation of maximum sustainable yield

FISH AND FISHERIES, Issue 4 2002
Mark N Maunder
Abstract The allocation of effort among fishing gears is as important as controlling effort with respect to both sustainable yield and ecosystem management. Differences in age-specific vulnerability to the fishing method can modify the maximum sustainable yield (MSY) that is obtainable from a fish stock. Different gears or methods are more or less selective for the species targeted, and MSY is rarely, if ever, attainable simultaneously for all species. The different fishing methods capture different types of nontarget species. Some methods will often be more profitable than others, and different user groups will prefer different methods. In many fisheries, it is unlikely that fishing can be limited to a single gear or method, so compromises among them will be required. Global MSY is discussed as a possible reference point for fisheries management. The yellowfin tuna fishery in the eastern Pacific Ocean (EPO) shows all the above characteristics and is used to illustrate effort allocation among fishing methods. [source]


A new role for MSY in single-species and ecosystem approaches to fisheries stock assessment and management

FISH AND FISHERIES, Issue 1 2001

In 1977, Peter Larkin published his now-famous paper, ,An epitaph for the concept of maximum sustained yield'. Larkin criticized the concept of single-species maximum sustained yield (MSY) for many reasons, including the possibility that it may not guard against recruitment failure, and the impossibility of maximising sustainable yields for all species simultaneously. However, in recent years, there has been a fundamental change in the perception of the fishing mortality associated with MSY (FMSY) as a limit to be avoided rather than a target that can routinely be exceeded. The concept of FMSY as a limit is embodied in several United Nations Food and Agriculture Organization (FAO) agreements and guidelines, and has now been incorporated into the US Magnuson,Stevens Fishery Conservation and Management Act. As a result, the United States now requires the development of overfishing definitions based on biological reference points that treat the FMSY as a limit reference point and must also define a lower limit on biomass below which rebuilding plans with strict time horizons must be developed. This represents a major paradigm shift from the previously mandated (but often unachieved) objective to simply maintain fishing mortalities at levels below those associated with recruitment overfishing. In many cases, it requires substantial reductions in current fishing mortality levels. Therefore, the necessity of the new paradigm is continually questioned. This paper draws on examples from several fisheries, but specifically focuses on the recent US experience illustrating the practical difficulties of reducing fishing mortality to levels below those corresponding to MSY. However, several studies suggest that even more substantial reductions in fishing mortality may be necessary if ecosystem considerations, such as multispecies interactions, maintenance of biodiversity and genetic diversity, and reduction of bycatch and waste, are taken into account. The pros and cons of moving beyond single-species assessment and management are discussed. A US plan for improving stock assessments indicates that even a ,basic' objective such as ,adequate baseline monitoring of all managed species' may be extremely costly. Thus, the suggestion of Larkin (1983, 1997) that the costs of research and management should not exceed 10,20% of the landed value of the catch may preclude comprehensive ecosystem management. More importantly, neither single-species nor ecosystem-based fisheries management is likely to improve appreciably unless levels of fishing capacity are aligned with resource productivity, as is currently being promoted by FAO and several individual nations. [source]


Development of a SWAT extension module to simulate riparian wetland hydrologic processes at a watershed scale

HYDROLOGICAL PROCESSES, Issue 16 2008
Yongbo Liu
Abstract Using a mass balance algorithm, this study develops an extension module that can be embedded in the commonly used Soil and Water Assessment Tool (SWAT). This module makes it possible to assess effects of riparian wetlands on runoff and sediment yields at a watershed scale, which is very important for aquatic ecosystem management but rarely documented in the literature. In addition to delineating boundaries of a watershed and its subwatersheds, the module groups riparian wetlands within a subwatershed into an equivalent wetland for modelling purposes. Further, the module has functions to compute upland drainage area and other parameters (e.g. maximum volume) for the equivalent wetland based on digital elevation model, stream network, land use, soil and wetland distribution GIS datasets. SWAT is used to estimate and route runoff and sediment generated from upland drainage area. The lateral exchange processes between riparian wetlands and their hydraulically connected streams are simulated by the extension module. The developed module is empirically applied to the 53 km2 Upper Canagagigue Creek watershed located in Southern Ontario of Canada. The simulation results indicate that the module can make SWAT more reasonably predict flow and sediment loads at the outlet of the watershed and better represent the hydrologic processes within it. The simulation is sensitive to errors of wetland parameters and channel geometry. The approach of embedding the module into SWAT enables simulation of hydrologic processes in riparian wetlands, evaluation of wetland effects on regulating stream flow and sediment loading and assessment of various wetland restoration scenarios. Copyright © 2008 John Wiley & Sons, Ltd. [source]


GUEST EDITORIAL: The interplay of pollinator diversity, pollination services and landscape change

JOURNAL OF APPLIED ECOLOGY, Issue 3 2008
Ingolf Steffan-Dewenter
Summary 1Pollinators are a functional group with high relevance for ensuring cross-pollination in wild plant populations and yields in major crops. Both pollinator declines and losses of pollination services have been identified in the context of habitat destruction and land use intensification. 2This editorial synthesizes and links the findings presented in seven papers in this Special Profile, focusing on pollinator diversity and plant,pollinator interactions in natural habitats and agricultural landscapes. 3The results contribute to our understanding of local and landscape scale effects of land use intensification on pollinator densities and diversity, and pollination functions in wild plant communities and crops. 4Synthesis and applications. We emphasize the exceptional coverage in pollination ecology ranging from basic ecological relationships to applied aspects of ecosystem services and ecosystem management, and conclude with identifying gaps in current knowledge and challenging research areas for the future. [source]


Meeting the ecological challenges of agricultural change: editors' introduction

JOURNAL OF APPLIED ECOLOGY, Issue 6 2003
S. J. Ormerod
Summary 1The global need for agricultural production has never been greater. Nor has it ever been more complex due to the needs to balance global food security, optimum production, technological innovation, the preservation of environmental functions and the protection of biodiversity. The role of ecologists in finding this balance is pivotal. 2In support of this role, ecologists now have very substantial experience of agricultural systems. We can understand, recognize and sometimes predict, at least qualitatively, the effects of pesticide applications, fertilizer use, drainage, crop choices and habitat modifications on farmland organisms, agro-ecosystems or other ecosystems influenced by agricultural land. 3In instances of greater uncertainty, for example under changing climates, where environmental stresses on ecosystems are interactive, and where ecosystem management or restoration must adapt to new technologies, the investigative skills and experience of ecologists are even more crucial in problem solving. 4There are, nevertheless, contrasting examples of good and bad practice in knowledge-transfer between ecologists and the communities who need our knowledge. The UK farm-scale evaluations of genetically modified crops, for example, involved ecologists at all stages from design and data collection to advocating policy. By contrast, many European agri-environment projects appear to have been developed and evaluated with only modest ecological advice. We advocate fuller involvement of ecologists in the development and evaluation of the European Union Common Agricultural Policy. 5This special profile of seven agriculturally related papers illustrates effectively the array of approaches used by applied ecologists in addressing agricultural questions: modelling, meta-analysis, surveys, transect studies, classical experiments, seedbank assays and process studies based on modern ecological methods. With over 20% of recent papers in the Journal of Applied Ecology reflecting agricultural issues, agro-ecology continues to represent one of the pre-eminent areas of applied ecology that is unlikely to diminish in importance. [source]


Current issues with fish and fisheries: editor's overview and introduction

JOURNAL OF APPLIED ECOLOGY, Issue 2 2003
S. J. Ormerod
Summary 1.,By any measure, fishes are among the world's most important natural resources. Annual exploitation from wild populations exceeds 90 million tonnes, and fish supply over 15% of global protein needs as part of total annual trade exceeding $US 55 billion. Additionally, with over 25 000 known species, the biodiversity and ecological roles of fishes are being increasingly recognised in aquatic conservation, ecosystem management, restoration and aquatic environmental regulation. 2.,At the same time, substantial management problems now affect the production, exploitable stocks, global diversity, trophic structure, habitat quality and local composition of fish communities. 3.,In marine systems, key issues include the direct effects of exploitation on fish, habitats and other organisms, while habitat or water quality problems arise also from the atmospheric, terrestrial and coastal environments to which marine systems are linked. In freshwaters, flow regulation and obstruction by dams, fragmentation, catchment management, pollution, habitat alterations, exotic fish introductions and nursery-reared fish are widespread issues. 4.,Management responses to the problems of fish and fisheries include aquatic reserves in both marine and freshwater habitats, and their effectiveness is now being evaluated. Policies on marine exploitation increasingly emphasise fishes as integral components of aquatic ecosystems rather than individually exploitable stocks, but the rationalisation of fishing pressures presents many challenges. In Europe, North America and elsewhere, policies on freshwaters encourage habitat protection, integrated watershed management and restoration, but pressures on water resources will cause continued change. All these management approaches require development and evaluation, and will benefit from a perspective of ecological understanding with ecologists fully involved. 5.,Synthesis and applications. Although making a small contribution to the Journal of Applied Ecology in the past, leading work on aquatic problems and fish-related themes appear increasingly in this and other mainstream ecology journals. As this special profile of five papers shows, significant contributions arise on diverse issues that here include the benefit of aquatic reserves, river restoration for fish, the accumulation of contaminants, interactions with predators, and the fitness of salmonids from nurseries. This overview outlines the current context in which papers on the applied ecology of fish and fisheries are emerging, and it identifies scope for further contributions. [source]


Applied issues with predators and predation: editor's introduction

JOURNAL OF APPLIED ECOLOGY, Issue 2 2002
S. J. Ormerod
Summary 1,The effects of predation are among the most pervasive in ecology. As parasitoids, parasites, grazers or top carnivores, predators have large influences on the distribution, density, dynamics and evolved traits of other organisms. Effects scale-up to influence community attributes such as species coexistence and ecosystems processes such as production or trophic cascades. 2,Increasingly, however, some of the largest predation issues fall clearly within the scope of applied ecology. They include instances where, due to their ecological attributes and trophic position: (i) predators are valuable to nature conservation, as biocontrol agents, as natural enemies, or as grazers used in rangeland or ecosystem management; (ii) natural or introduced predators are viewed negatively due to effects on conservation, agriculture, forestry, hunting or disease transmission; (iii) predators are affected by human activities such as resource exploitation, or from exposure to factors such as biomagnified pollutants and disturbance; (iv) predators are controversial because different groups view them as either desirable or undesirable. 3,In all these cases, ecologists have a pivotal rôle in facilitating appropriate management. For valued predators, this involves developing sufficient ecological understanding to optimize habitat, increase prey abundance or to reinforce, establish or reintroduce desirable species. For predators considered undesirable, management can involve direct control. In other cases, predation and its consequences can be mitigated by deterrent, exclusion, supplementary feeding, habitat management to favour prey, predator swamping, or by compensating losses financially. These latter strategies are often used where predators are themselves considered too valuable to remove or control. 4,This collection of seven papers illustrates many of these themes by examining contrasting aspects of the applied ecology of Eurasian lynx; by further probing the interaction between predatory birds and red grouse; by exploring the effects of weather on biocontrol; and by illustrating effects on plant species where grazing or seed predation play a dominant rôle. 5,A key lesson from these and other recent papers in the Journal of Applied Ecology is that the successful management of predators depends invariably on understanding adequately the exact ecological context in which predator,prey interactions take place and in which problems arise. With predator-related issues growing rather than diminishing, ecologists will need sufficient resources to maintain current research if they are to provide the understanding required to offer and evaluate sound management. [source]


Factors affecting the distribution patterns of zebra and wildebeest in a resource-stressed environment

AFRICAN JOURNAL OF ECOLOGY, Issue 1 2010
Rosemary Groom
Abstract Understanding the spatial dynamics of landscape use by free-ranging herbivores is integral for successful ecosystem management. We used binary logistic regression analyses to determine the relative importance of biotic, abiotic and human factors in influencing the distribution (presence/absence) of wild grazers on two Maasai ranches in Kenya's Amboseli-Tsavo ecosystem. Both ranches had low grass biomass and suffered from regular droughts. We found that grazers consistently located themselves where grass biomass was highest, usually irrespective of grass quality, suggesting that forage quantity may be the limiting factor where grass biomass is generally low. The availability of surface water had no significant effect on the likelihood of grazers being present, even in the dry season. Résumé La bonne compréhension de la dynamique spatiale de l'utilisation du paysage par les herbivores qui paissent en liberté fait partie intégrante de la gestion réussie d'un écosystème. Nous avons employé des analyses de régression logistique binaire pour déterminer l'importance relative des facteurs biotiques, abiotiques et humains dans l'influence sur la distribution (présence/absence) d'herbivores sauvages sur deux ranches masaï de l'écosystème Amboseli-Tsavo, au Kenya. Les deux ranches avaient une faible biomasse herbeuse et souffraient de sécheresses régulières. Nous avons découvert que les herbivores brouteurs se trouvaient de façon constante là où la biomasse herbeuse était la plus grande, sans tenir compte, d'habitude, de la qualité de l'herbe; ceci suggère que la quantité de fourrage pourrait être le facteur imitant là où la biomasse herbeuse est généralement faible. La disponibilité de l'eau de surface n'avait pas d'effet significatif sur la probabilité de la présence des herbivores, même en saison sèche. [source]


Plant community properties predict vegetation resilience to herbivore disturbance in the Arctic

JOURNAL OF ECOLOGY, Issue 5 2010
James D. M. Speed
Summary 1.,Understanding the impact of disturbance on vegetation and the resilience of plant communities to disturbance is imperative to ecological theory and environmental management. In this study predictors of community resilience to a simulated natural disturbance are investigated. Responses to disturbance are examined at the community, plant functional type and species level. 2.,Field experiments were set up in seven tundra plant communities, simulating disturbance based on the impact of grubbing by an increasing herbivore population of pink-footed geese (Anser brachyrhynchus). The short-term resilience of communities was assessed by comparing community dissimilarity between control plots and plots subject to three disturbance intensities based on the foraging impact of these geese. Potential for long-term recovery was evaluated across different disturbance patch sizes. 3.,Resilience to disturbance varied between communities; those with higher moss cover and higher soil moisture, such as wetlands and mires, were most resilient to disturbance. 4.,The wetter communities demonstrated greater long-term recovery potential following disturbance. In wetland communities, vegetative recovery of vascular plants and moss was greater in smaller disturbed patches and at the edges of patches. 5.,The response of vegetation to disturbance varied with intensity of disturbance, plant community and plant species. The use of functional type classifications only partially explained the variation in species responses to disturbance across communities, thus their use in predicting community changes was limited. 6.,Synthesis. The impact of disturbance is shown to be plant-community specific and related to the initial abiotic and biotic properties of the community. By showing that resilience is partly predictable, the identification of disturbance-susceptible communities is possible, which is of relevance for ecosystem management. [source]


Approaches to landcare,a century of soil conservation in Iceland

LAND DEGRADATION AND DEVELOPMENT, Issue 2 2005
A. Arnalds
Abstract Organized soil conservation in Iceland began in 1907, as a response to severe land degradation and desertification that was threatening the existence of several communities. During the first 75 years, many of the most threatening areas of accelerated soil erosion were fenced and seeded with sand stabilizers. These projects had a high success rate, halting the advancement of sand dunes and other forms of highly accelerated erosion. However, they were limited in scope, and often concentrated on the symptoms of the problems rather than the underlying causes, such as improper grazing management. On a national scale, not enough was being achieved in mitigating the extensive ecosystem degradation. This period of soil conservation in Iceland was characterized by single-issue, top-down approaches, a lack of appropriate incentives for soil conservation and weak laws for protection of the rangelands. During the last two decades there has been a gradual shift to more participatory strategies, community involvement, and ecosystem management for multiple benefits. These changes have greatly increased community involvement in projects, stimulated conservation awareness and improved land use. The ties between agricultural policy and soil-conservation issues are also being strengthened, especially by linking part of governmental subsidies for sheep production to land-use factors. Copyright © 2005 John Wiley & Sons, Ltd. [source]


Toward an improved legislative framework for China's land degradation control

NATURAL RESOURCES FORUM, Issue 1 2008
Zhou Ke
Abstract The Chinese government has recently been attaching increasing importance to the application of effective legal tools to tackle land degradation (LD) issues. Based on the concept of sustainable development, China began developing and reaping the benefits of environmental and natural resources legislation including LD control regulations in the 1990s. In the past three years, some central-western provinces in China have been implementing a "People's Republic of China/Global Environment Facility (PRC/GEF) Partnership on LD Control of Dryland Ecosystems", which is based on an integrated ecosystem management (IEM) approach. IEM is designed to achieve a balanced, scientific and participatory approach to natural resources management, which creates the potential to improve the quality of Chinese environmental law and policy procedures. The paper studies the existing Chinese national laws and regulations pertinent to LD control within 9 areas covering land, desertification, soil erosion, grassland, forest, water, agriculture, wild animals and plants, and environment protection in detail, against IEM principles and basic legal elements. The main objective is to identify problems and provide feasible solutions and recommendations for the improvement of the existing laws and regulations. The authors conclude that the development of an improved national legislative framework is essential if LD control is to be successfully achieved. The paper is partly based on Component 1 , Improving Policies, Laws and Regulations for Land Degradation Control under PRC/GEF Partnership on Land Degradation in Dryland Ecosystems (TA 4357). [source]


Junk-food in marine ecosystems

OIKOS, Issue 7 2008
Henrik Österblom
The abundance and availability of food are critical determininants of reproductive success and population dynamics of marine top predators. However, recent work has indicated that the quality of the food may also be critically important for some marine predators. The ,junkfood hypothesis' was originally suggested as a potential explanation for a dramatic population decline of Stellers sea lions Eumetopias jubatus in the Gulf of Alaska. According to the hypothesis, a dietary switch to prey of low energy content led to detrimental effects on the population of sea lions. A number of observations indicate that the hypothesis is relevant for several population parameters. Recent work on piscivorous seabirds has provided substantial evidence indicating the relevance of this hypothesis in food webs in e.g. the North Pacific, the North Sea and the Baltic Sea. The emergence of ,junk-food' in these systems may be coupled to large scale changes in climatological and oceanographic forcing, although predation, fishing and competition provide additional plausible hypotheses. It may be possible to predict which kinds of animals will be particularly sensitive to food quality; these seem to be species with limited ability to carry food loads, with energetically-expensive foraging behaviour, and with digestive anatomy evolved to minimize mass at the cost of digestive efficiency. This review suggests that the junk-food hypothesis is a highly relevant factor in relation to sustaining ecosystem resilience, and is an important consideration in ecosystem management. Sustaining healthy populations of marine top-predators requires an understanding of the role of food quality, in addition to food abundance and availability. [source]


Tooth wear and dental pathology at the advent of agriculture: New evidence from the Levant

AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2006
Vered Eshed
Abstract Differences in patterns of diet and subsistence through the analysis of dental pathology and tooth wear were studied in skeletal populations of Natufian hunter-gatherers (10,500,8300 BC) and Neolithic populations (8300,5500 BC, noncalibrated) from the southern Levant. 1,160 Natufians and 804 Neolithic teeth were examined for rate of attrition, caries, antemortem tooth loss, calculus, periapical lesions, and periodontal processes. While the Natufian people manifest a higher rate of dental attrition and periodontal disease (36.4% vs. 19%), Neolithic people show a higher rate of calculus. Both populations manifested low and similar rates of caries (6.4% in the Natufian vs. 6.7% in the Neolithic), periapical lesions (not over 1.5%), and antemortem tooth loss (3.7% vs. 4.5%, respectively). Molar wear pattern in the Neolithic is different than in the Natufian. The current study shows that the dental picture obtained from the two populations is multifactorial in nature, and not exclusively of dietary origin, i.e., the higher rate and unique pattern of attrition seen in the Natufian could result from a greater consumption of fibrous plants, the use of pestles and mortars (which introduce large quantities of stone-dust to the food), and/or the use of teeth as a "third hand." The two major conclusions of this study are: 1) The transition from hunting and gathering to a food-producing economy in the Levant did not promote changes in dental health, as previously believed. This generally indicates that the Natufians and Neolithic people of the Levant may have differed in their ecosystem management (i.e., gathering vs. growing grains), but not in the type of food consumed. 2) Changes in food-preparation techniques and nondietary usage of the teeth explain much of the variation in tooth condition in populations before and after the agricultural revolution. Am J Phys Anthropol, 2006. © 2005 Wiley-Liss, Inc. [source]


Defining the Limits of Restoration: The Need for Realistic Goals

RESTORATION ECOLOGY, Issue 1 2000
Joan G. Ehrenfeld
The search for a universal statement of goals for ecological restoration continues to generate discussion and controversy. I discuss the diverse roots of restoration ecology, and show how the complex lineages within the field have led to diverse, and divergent, sets of goals. I then review the three major themes that currently are used to develop statements of goals: restoration of species, restoration of whole ecosystems or landscapes, and the restoration of ecosystem services, and point out both the advantages and the limitations and problems associated with each category. Finally, I suggest that restoration ecology would be better served by recognizing that the diversity of conditions requiring restoration demands much flexibility in goal setting, and that restorationists should seek to develop guidelines for defining the sets of conditions under which different kinds of goals are appropriate. I further suggest that goals would be more easily and more appropriately set if restorationists would set forth at the outset the true scope and limitations of what is possible in a given project. Key words: goal-setting, wetlands, conservation biology, ecosystem management, ecosystem services, landscape management. [source]


From plant,microbe interactions to symbiogenetics: a universal paradigm for the interspecies genetic integration

ANNALS OF APPLIED BIOLOGY, Issue 3 2009
I.A. Tikhonovich
Abstract Beneficial plant,microbe symbioses are based on the integration of genetic material from diverse organisms resulting in formation of superorganism genetic systems. Analysis of their functions and evolution requires the establishment of a new biological discipline, proposed to be called symbiogenetics, which provides a basis for fundamental and applied research of the genetic control over different (symbiotic and biocenotic) biotic interactions. In ecology and agrobiology, the approaches of symbiogenetics are indispensable for optimising the interactions between the plants and the beneficial microbes to be used in ecosystem management and in sustainable crop production in which hazardous fertilisers and pesticides should be replaced by environmentally friendly microbial inoculants. [source]


An ecosystem modelling approach to deriving viable harvest strategies for multispecies management of the Northern Gulf of California

AQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 4 2009
Diego Lercari
Abstract 1.An ecosystem analysis was developed focusing on resource exploitation and biodiversity conservation for the Northern Gulf of California. The main tools employed were a trophic ecosystem model and time dynamic simulations. 2.The ecosystem was represented by an Ecopath model that included 34 functional groups, from primary producers to top predators. It included relevant species in the area such as commercially important shrimp (e.g. Litopenaeus stylirostris) and highly endangered species (Phocoena sinus and Totoaba macdonaldi). 3.Temporal simulations of changing fishing effort allowed the evaluation of fishing impact on the ecosystem components and, particularly, on protected species. Formal optimization methods were applied with the purpose of searching viable temporal patterns of fishing effort that might minimize social, economic and conservationist conflicts in the area. 4.The results of those simulations showed the capability of the model to represent reference temporal series of relative biomass. The search for viable fishing strategies resulted in effort allocation consistent with those proposed by other studies; that is, a decrease in the industrial shrimp fleet (35,65%), a decrease in the gillnet fishing fleet (52,57%), and an increase of the artisanal shrimp fishery (63,222%). 5.The main conflicts in the Northern Gulf of California seem to take place between social and conservation interests, while the economic and ecological benefits seem to be relatively independent. The next steps towards conflict resolution and ecosystem management should consider the design and operation of MPAs already established in the region. Copyright © 2008 John Wiley & Sons, Ltd. [source]


Petroleum hydrocarbon contamination in boreal forest soils: a mycorrhizal ecosystems perspective

BIOLOGICAL REVIEWS, Issue 2 2007
Susan J. Robertson
Abstract The importance of developing multi-disciplinary approaches to solving problems relating to anthropogenic pollution is now clearly appreciated by the scientific community, and this is especially evident in boreal ecosystems exposed to escalating threats of petroleum hydrocarbon (PHC) contamination through expanded natural resource extraction activities. This review aims to synthesize information regarding the fate and behaviour of PHCs in boreal forest soils in both ecological and sustainable management contexts. From this, we hope to evaluate potential management strategies, identify gaps in knowledge and guide future research. Our central premise is that mycorrhizal systems, the ubiquitous root symbiotic fungi and associated food-web communities, occupy the structural and functional interface between decomposition and primary production in northern forest ecosystems (i.e. underpin survival and productivity of the ecosystem as a whole), and, as such, are an appropriate focal point for such a synthesis. We provide pertinent basic information about mycorrhizas, followed by insights into the ecology of ecto- and ericoid mycorrhizal systems. Next, we review the fate and behaviour of PHCs in forest soils, with an emphasis on interactions with mycorrhizal fungi and associated bacteria. Finally, we summarize implications for ecosystem management. Although we have gained tremendous insights into understanding linkages between ecosystem functions and the various aspects of mycorrhizal diversity, very little is known regarding rhizosphere communities in PHC-contaminated soils. This makes it difficult to translate ecological knowledge into environmental management strategies. Further research is required to determine which fungal symbionts are likely to survive and compete in various ecosystems, whether certain fungal - plant associations gain in ecological importance following contamination events, and how PHC contamination may interfere with processes of nutrient acquisition and exchange and metabolic processes. Research is also needed to assess whether the metabolic capacity for intrinsic decomposition exists in these ecosystems, taking into account ecological variables such as presence of other organisms (and their involvement in syntrophic biodegradation), bioavailability and toxicity of mixtures of PHCs, and physical changes to the soil environment. [source]