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Long-term Implications (long-term + implication)
Selected AbstractsPolicies, Interventions and Institutional Change in Pastoral Resource Management in Borana, Southern EthiopiaDEVELOPMENT POLICY REVIEW, Issue 4 2004Abdul B. Kamara The Borana rangelands of Southern Ethiopia are characterised by extensive livestock production under a communal land-use system that has evolved in response to variable rainfall and uncertain production conditions. However, the last two decades have witnessed an increasing privatisation of rangelands for crop production and private grazing. The results of a quantitative assessment are used to develop a framework for assessing the drivers of change and their long-term implications. It is concluded that certain national policies have resulted in conflicts of authority between traditional and formal systems, creating an avenue for spontaneous enclosures, associated conflicts and decreasing human welfare. [source] A catchment scale evaluation of the SIBERIA and CAESAR landscape evolution modelsEARTH SURFACE PROCESSES AND LANDFORMS, Issue 8 2010GR Hancock Abstract Landscape evolution models provide a way to determine erosion rates and landscape stability over times scales from tens to thousands of years. The SIBERIA and CAESAR landscape evolution models both have the capability to simulate catchment,wide erosion and deposition over these time scales. They are both cellular, operate over a digital elevation model of the landscape, and represent fluvial and slope processes. However, they were initially developed to solve research questions at different time and space scales and subsequently the perspective, detail and process representation vary considerably between the models. Notably, CAESAR simulates individual events with a greater emphasis on fluvial processes whereas SIBERIA averages erosion rates across annual time scales. This paper describes how both models are applied to Tin Camp Creek, Northern Territory, Australia, where soil erosion rates have been closely monitored over the last 10 years. Results simulating 10,000 years of erosion are similar, yet also pick up subtle differences that indicate the relative strengths and weaknesses of the two models. The results from both the SIBERIA and CAESAR models compare well with independent field data determined for the site over different time scales. Representative hillslope cross-sections are very similar between the models. Geomorphologically there was little difference between the modelled catchments after 1000 years but significant differences were revealed at longer simulation times. Importantly, both models show that they are sensitive to input parameters and that hydrology and erosion parameter derivation has long-term implications for sediment transport prediction. Therefore selection of input parameters is critical. This study also provides a good example of how different models may be better suited to different applications or research questions. Copyright © 2010 John Wiley & Sons, Ltd and Commonwealth of Australia [source] Source Zone Natural Attenuation at Petroleum Hydrocarbon Spill Sites,I: Site-Specific Assessment ApproachGROUND WATER MONITORING & REMEDIATION, Issue 4 2006Paul Johnson This work focuses on the site-specific assessment of source zone natural attenuation (SZNA) at petroleum spill sites, including the confirmation that SZNA is occurring, estimation of current SZNA rates, and anticipation of SZNA impact on future ground water quality. The approach anticipates that decision makers will be interested in answers to the following questions: (1) Is SZNA occurring and what processes are contributing to SZNA? (2) What are the current rates of mass removal associated with SZNA? (3) What are the longer-term implications of SZNA for ground water impacts? and (4) Are the SZNA processes and rates sustainable? This approach is a data-driven, macroscopic, multiple-lines-of-evidence approach and is therefore consistent with the 2000 National Research Council's recommendations and complementary to existing dissolved plume natural attenuation protocols and recent modeling work published by others. While this work is easily generalized, the discussion emphasizes SZNA assessment at petroleum hydrocarbon spill sites. The approach includes three basic levels of data collection and data reduction (Group I, Group II, and Group III). Group I measurements provide evidence that SZNA is occurring. Group II measurements include additional information necessary to estimate current SZNA rates, and group III measurements are focused on evaluating the long-term implications of SZNA for source zone characteristics and ground water quality. This paper presents the generalized site-specific SZNA assessment approach and then focuses on the interpretation of Group II data. Companion papers illustrate its application to source zones at a former oil field in California. [source] Offshore renewable energy: ecological implications of generating electricity in the coastal zoneJOURNAL OF APPLIED ECOLOGY, Issue 4 2005ANDREW B. GILL Summary 1Global-scale environmental degradation and its links with non-renewable fossil fuels have led to an increasing interest in generating electricity from renewable energy resources. Much of this interest centres on offshore renewable energy developments (ORED). The large scale of proposed ORED will add to the existing human pressures on coastal ecosystems, therefore any ecological costs and benefits must be determined. 2The current pressures on coastal ecology set the context within which the potential impacts (both positive and negative) of offshore renewable energy generation are discussed. 3The number of published peer-review articles relating to renewable energy has increased dramatically since 1991. Significantly, only a small proportion of these articles relate to environmental impacts and none considers coastal ecology. 4Actual or potential environmental impact can occur during construction, operation and/or decommissioning of ORED. 5Construction and decommissioning are likely to cause significant physical disturbance to the local environment. There are both short- and long-term implications for the local biological communities. The significance of any effects is likely to depend on the natural disturbance regime and the stability and resilience of the communities. 6During day-to-day operation, underwater noise, emission of electromagnetic fields and collision or avoidance with the energy structures represent further potential impacts on coastal species, particularly large predators. The wider ecological implications of any direct and indirect effects are discussed. 7Synthesis and applications. This review demonstrates that offshore renewable energy developments will have direct and, potentially, indirect consequences for coastal ecology, with these effects occurring at different scales. Ecologists should be involved throughout all the phases of an ORED to ensure that appropriate assessments of the interaction of single and multiple developments with the coastal environment are undertaken. [source] Early Family Transitions and Depressive Symptom Changes From Adolescence to Early AdulthoodJOURNAL OF MARRIAGE AND FAMILY, Issue 1 2008Alan Booth Some research and theory suggest that early cohabitation, parenthood, and marriage have negative long-term implications. Nevertheless, in the context of their resources and opportunities, early transitions may represent positive choices for some individuals. We studied the family and personal characteristics of young adults (N = 8,172) who did, versus those who did not, make early family transitions. We assessed changes in their depressive symptoms from adolescence to young adulthood. Individuals who made early family transitions were disadvantaged in many respects, but differed little from those who did not with respect to changes in depressive symptoms. That they stay "even" with those who do not make transitions suggests that some young adults make positive choices from among limited options. [source] ADJUSTMENT OF STREAM CHANNEL CAPACITY FOLLOWING DAM CLOSURE, YEGUA CREEK, TEXAS,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 6 2002Anne Chin ABSTRACT: In Yegua Creek, a principal tributary of the Brazos River in Texas, surveys of a 19 km channel reach downstream of Somerville Dam show that channel capacity decreased by an average of 65 percent in a 34 year period following dam closure. The decrease corresponds with an approximately 85 percent reduction in annual flood peaks. Channel depth has changed the most, decreasing by an average of 61 percent. Channel width remained stable with an average decrease of only 9 percent, reflecting cohesive bank materials along with the growth of riparian vegetation resulting from increased low flows during dry summer months. Although large changes in stream channel geometry are not uncommon downstream of dams, such pronounced reductions in channel capacity could have long-term implications for sediment delivery through the system. [source] Airway function measurements and the long-term follow-up of survivors of preterm birth with and without chronic lung diseasePEDIATRIC PULMONOLOGY, Issue 6 2006Indra Narang MRCPCH Abstract This seventh paper in a review series on different aspects of chronic lung disease following preterm birth focuses on the current knowledge of respiratory symptoms, airway function, airway hyperresponsiveness, and exercise capacity from childhood to adulthood. This paper further considers the long-term implications of these studies for both future research and clinical practice. Pediatr Pulmonol. © 2006 Wiley-Liss, Inc. [source] Gastrointestinal parasites of the chimpanzee population introduced onto Rubondo Island National Park, TanzaniaAMERICAN JOURNAL OF PRIMATOLOGY, Issue 4 2010Klára J. Petr, elková Abstract The release of any species into a novel environment can evoke transmission of parasites that do not normally parasitize the host as well as potentially introducing new parasites into the environment. Species introductions potentially incur such risks, yet little is currently known about the parasite fauna of introduced primate species over the long term. We describe the results of long-term monitoring of the intestinal parasite fauna of an unprovisioned, reproducing population of chimpanzees introduced 40 years earlier (1966,1969) onto Rubondo Island in Lake Victoria, Tanzania, a non-native habitat for chimpanzees. Two parasitological surveys (March 1997,October 1998 and October 2002,December 2005) identified Entamoeba spp. including E. coli, Iodamoeba buetschlii, Troglodytella abrassarti, Chilomastix mesnili, Trichuris sp., Anatrichosoma sp., Strongyloides spp., Strongylida fam. gen. sp., Enterobius anthropopitheci, Subulura sp., Ascarididae gen. sp., and Protospirura muricola. The parasite fauna of the Rubondo chimpanzees is similar to wild chimpanzees living in their natural habitats, but Rubondo chimpanzees have a lower prevalence of strongylids (9%, 3.8%) and a higher prevalence of E. anthropopitheci (8.6%, 17.9%) than reported elsewhere. Species prevalence was similar between our two surveys, with the exception of Strongyloides spp. being higher in the first survey. None of these species are considered to pose a serious health risk to chimpanzees, but continued monitoring of the population and surveys of the parasitic fauna of the two coinhabitant primate species and other animals, natural reservoir hosts of some of the same parasites, is important to better understand the dynamics of host,parasite ecology and potential long-term implications for chimpanzees introduced into a new habitat. Am. J. Primatol. 72:307,316, 2010. © 2009 Wiley-Liss, Inc. [source] Vascular reconstruction in lower limb musculoskeletal tumoursANZ JOURNAL OF SURGERY, Issue 9 2009J. Ian Spark Abstract Background:, Individual experience in the investigative, planning and operative aspects of lower limb musculoskeletal tumours is often small, making comparison between results difficult. The aim of the study was to describe the recent experience of a single tertiary referral unit performing limb salvage surgery, to identify areas of concern that are amenable to intervention and to provide clinicians an understanding of the surgical options. Methods:, Nine patients with peripheral limb musculoskeletal tumours are described. Four patients had a leiomyosarcoma, and one each of osteosarcoma, synovial chondrosarcoma, synovial sarcoma, liposarcoma and recurrent malignant peripheral nerve sheath tumour. Results:, Thirty-day mortality was nil. Two patients (one with a leiomyosarcoma and one with an osteosarcoma) died at 6 months follow-up because of pulmonary metastases. One patient with synovial chondrosarcoma developed a local recurrence and underwent an above-knee amputation. Six patients at 18 months follow-up are alive with no evidence of local recurrence and a functional lower limb. Conclusion:, These cases are a challenge to the clinicians, radiologists and pathologists. Review by a multidisciplinary team can produce successful results with low post-operative morbidity and mortality. Longer follow-up is required to determine the long-term implications. [source] Long-term after-effects of fertilisation on the restoration of calcareous grasslandsAPPLIED VEGETATION SCIENCE, Issue 2 2008N.A.C. Smits Question: What are the long-term implications of former fertilisation for the ecological restoration of calcareous grasslands? Location: Gerendal, Limburg, The Netherlands. Methods: In 1970, ten permanent plots were established in just abandoned agricultural calcareous grassland under a regime of annual mowing in August. From 1971 to 1979, two different fertiliser treatments were applied twice a year to a subset of the plots (artificial fertiliser with different proportions of nitrogen and phosphorus). The vegetation of the plots was recorded yearly and vegetation biomass samples were taken for peak standing crop and total amounts of nitrogen, phosphorus and potassium. Species composition and floristic diversity were analysed over the research period (1970,2006) and between the treatments, including the use of multivariate techniques (Detrended Correspondence Analysis). Results: In terms of species number, there is a clear optimum 10 to 20 years after fertilisation has been terminated. Afterwards, there is a slow decrease; no new species appear and species of more nutrient-rich conditions gradually disappear. For the fertilised plots that received a relatively high proportion of N, effects are found only in the first years, whereas, for the plots that received a relatively high proportion of P, long-term after-effects are found in species composition, peak standing crop, total amounts of phosphorus in biomass, and in soil phosphorus data. Conclusions: The effect of artificial fertiliser with a large amount of nitrogen disappears in less than ten years when mown in August, including removal of the hay. This is a promising result for restoration of N-enriched calcareous grasslands, as the applied dose of nitrogen in this experiment largely exceeds the extra input of nitrogen via atmospheric deposition. Application of fertiliser with a large amount of phosphorus, however, has effects even more than 25 years after the last addition. There are no prospects that this effect will become reduced in the near future under the current mowing management. [source] Disturbance affects spatial patterning and stand structure of a tropical rainforest treeAUSTRAL ECOLOGY, Issue 4 2010BRUCE L. WEBBER Abstract The distribution and spatial patterns of plant populations in natural ecosystems have recently received much attention; yet the impacts of human-induced disturbances on these patterns and underlying processes remain poorly understood. We used the sub-canopy tree, Ryparosa kurrangii (Achariaceae), to explore the possible effects of such disturbances on stand structure and spatial patterning in an Australian tropical rainforest. We studied three populations that differed in their extent of habitat modification: anthropogenic disturbance (proximate settlement and roads) and internal damage by an invasive alien species, the feral pig (Sus scrofa). Populations were mapped, characterized, and three size cohorts (seedlings, saplings, trees) were analysed using a suite of spatial point pattern analyses (univariate: Diggle's G and F and Ripley's K; bivariate: Diggle's G and Ripley's K). Ryparosa kurrangii has a typical stand structure for a sub-canopy tree species, but occurs at high densities locally (>400 stems ha,1). At all sites, the tree cohort were randomly distributed and saplings were spatially aggregated at distances of up to 2,3 m. Between sites there were distinct differences in the size structure and spatial pattern of seedlings, the cohort most affected by recent habitat modification. That is, the least disturbed site had no aggregation among seedlings, the site with the greatest anthropogenic disturbance had many small, clustered seedlings that were spatially associated with trees, and the site with pig damage had clustered seedlings that had no spatial relationship with trees. We propose that habitat modification by anthropogenic and pig disturbance disrupts seed dispersal and establishment regimes, which leads to altered seedling spatial patterns. These disturbances could have long-term implications for the population structure and health of R. Kurrangii. [source] General obstetrics: Preterm birth and multiple pregnancy in European countries participating in the PERISTAT projectBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 5 2006B Blondel Objective, To compare rates of preterm birth among multiple births in European countries, to estimate their contribution to overall preterm birth rates and to explore factors which could explain differences between preterm birth rates. Design, Analyses of data from vital statistics, birth registers or national samples of births. Setting, Eleven member states of the European Union. Population, All live births or representative samples of births at national or regional level for the year 2000 or most recent year. Methods, Description of rates of preterm birth before 37 and 32 weeks, estimation of population attributable risks (PAR), study of associations between preterm birth rates in multiples and singletons and nonspontaneous labour using Spearman's rank correlation coefficient. Main outcome measures, Preterm birth rates, PAR, proportions of deliveries with nonspontaneous onset (caesarean sections before labour or induction of labour). Results, The proportion of multiple births before 37 weeks varied from 68.4% in Austria to 42.2% in the Republic of Ireland. In half of the countries, over 20% of all preterm births were attributable to multiple births. A strong association was found between the proportions of births before 37 weeks among multiple and singleton births (r= 0.81; P < 0.001). An association was observed between the rates of preterm birth and the proportions of deliveries with nonspontaneous onset among twins. Conclusions, Wide variations in rates of preterm births and deliveries with nonspontaneous onset were found between countries, suggesting marked differences in clinical practice which could have long-term implications for the health of children from multiple births. [source] The prevalence of psychiatric disorder in children attending a school for pupils with emotional and behavioural difficultiesBRITISH JOURNAL OF SPECIAL EDUCATION, Issue 4 2001Elizabeth Cassidy The research presented in this article suggests that young people attending schools for pupils with emotional and behavioural difficulties are more likely to experience concurrent psychiatric disorders (comorbidity) than their peers in mainstream schools. Dr Cassidy (Consultant in Child and Adolescent Psychiatry), Dr James (Consultant and Honorary Senior Lecturer in Child and Adolescent Psychiatry) and Dr Wiggs (Research Psychologist) used questionnaires and interviews with parents and teachers, together with pupil self-reporting, to gather their data. The two-stage investigation suggested that 89% of the adolescents in one school for pupils with EBD met established criteria for the diagnosis of a psychiatric disorder. Conduct disorder and attention deficit hyperactivity disorder (ADHD) emerged as the most common psychiatric difficulties, but emotional disorders were also prominent in the data. These untreated problems are likely to have significant long-term implications for the psychological and educational development of the pupils concerned, and the authors speculate on some of the ways in which psychiatric and education services might work together in order to improve the outlook. [source] | ||||||||||||||||||||||