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Situ Conservation (situ + conservation)
Selected AbstractsEvolutionary response of landraces to climate change in centers of crop diversityEVOLUTIONARY APPLICATIONS (ELECTRONIC), Issue 5-6 2010Kristin L. Mercer Abstract Landraces cultivated in centers of crop diversity result from past and contemporary patterns of natural and farmer-mediated evolutionary forces. Successful in situ conservation of crop genetic resources depends on continuity of these evolutionary processes. Climate change is projected to affect agricultural production, yet analyses of impacts on in situ conservation of crop genetic diversity and farmers who conserve it have been absent. How will crop landraces respond to alterations in climate? We review the roles that phenotypic plasticity, evolution, and gene flow might play in sustaining production, although we might expect erosion of genetic diversity if landrace populations or entire races lose productivity. For example, highland maize landraces in southern Mexico do not express the plasticity necessary to sustain productivity under climate change, but may evolve in response to altered conditions. The outcome for any given crop in a given region will depend on the distribution of genetic variation that affects fitness and patterns of climate change. Understanding patterns of neutral and adaptive diversity from the population to the landscape scale is essential to clarify how landraces conserved in situ will continue to evolve and how to minimize genetic erosion of this essential natural resource. [source] Variability and divergence in Pongamia pinnata (L.) Pierre germplasm , a candidate tree for biodieselGCB BIOENERGY, Issue 6 2009N. SUNIL Abstract Three explorations were undertaken in South East Coastal zone of India covering parts of Andhra Pradesh (AP) and Orissa states to collect Pongamia pinnata (L.) Pierre germplasm during March,June 2007. A total of 123 accessions were collected and seed data recorded were analyzed for morphometric traits viz., seed length, seed width, seed thickness, 100-seed weight and oil content. Variation in the collected germplasm was analyzed using anova, simple measures of variation and D2 statistics. Significant genetic variability between seed traits and oil content and association among the seed traits was recorded. Phenotypic variance was higher than genotypic variance for all the characters indicating dominant role of environment. High heritability (broad sense) for 100-seed weight (97.6%) and oil content (86.7%) indicated the reliability of these characters as selection criteria for plus trees. Genetic gain was maximum for 100-seed weight (62.6%) followed by oil content (30.5%). D2 analysis grouped the accessions into 12 clusters. Cluster XII and cluster IX were the most diverse based on the intercluster distance. Based on the observed diversity, Chittoor, Srikakulam and Adilabad districts of AP are most suitable for collecting diverse germplasm lines and also for in situ conservation. [source] Using economic instruments to overcome obstacles to in situ conservation of biodiversityINTEGRATIVE ZOOLOGY (ELECTRONIC), Issue 1 2006Jeffrey A. McNEELY Abstract The leading direct cause of the loss of biodiversity is habitat alteration and disruption. If we are to address this cause directly, we need to find ways of changing the behavior of rural people. Experience has shown that this is done most effectively through the use of economic instruments, ranging from taxes that discourage over-exploitation, to direct payments for conservation activities carried out by rural land-owners or those occupying the land. In many parts of the world, governments provide incentives such as tax breaks to private land-owners. Other countries recognize specific use rights on particular parts of the land, enabling the land-owners to earn appropriate benefits. Since many protected areas have resident human populations, it is especially important that they be encouraged to contribute to the objectives of the protected area, and economic incentives offer an important way of doing so; they might, for example, be given employment in the protected area or in associated tourism activities. Direct payments to farmers for conserving watersheds is becoming increasingly popular, in both developed and developing countries. Improved conservation will require both removing perverse subsidies and developing a wide range of approaches for rewarding land-owners for biodiversity conservation activities. [source] The role of the Species Survival Plan in Maned wolf Chrysocyon brachyurus conservationINTERNATIONAL ZOO YEARBOOK, Issue 1 2010N. SONGSASEN The Association of Zoos and Aquariums Maned Wolf Species Survival Plan (MWSSP) was established almost 25 years ago. The goals of the MWSSP are to (1) maintain a viable self-sustaining captive population in North America, (2) enhance health and well-being of individuals living in North American zoos and (3) promote conservation of this species through education and field-conservation initiatives. Since its inception, the MWSSP and member institutions have supported studies on nutrition, medical management, behaviour and reproductive biology, and published a husbandry manual, which serves as a guide for captive management of Maned wolves Chrysocyon brachyurus in North and South American zoos. Furthermore, the MWSSP has provided funding for field studies aimed at identifying potential threats to wild populations in range countries, including Brazil, Bolivia and Argentina, as well as for the first Population and Habitat Viability Assessment Workshop for this species. Finally, the MWSSP has played an active role in promoting education and outreach efforts in both the United States and range countries. In this paper, we review and discuss the roles of the MWSSP in ex situ and in situ conservation of the Near Threatened Maned wolf. [source] Rhinoceros behaviour: implications for captive management and conservationINTERNATIONAL ZOO YEARBOOK, Issue 1 2006M. HUTCHINS All species of rhinoceros are, to varying degrees, threatened with extinction because of poaching, habitat loss, human-rhinoceros conflict, hunting and civil unrest. Clearly the threats facing the five remaining species (Black rhinoceros Diceros bicornis, White rhinoceros Ceratotherium simum, Greater one-horned rhinoceros Rhinoceros unicornis, Javan rhinoceros Rhinoceros sondaicus and Sumatran rhinoceros Dicerorhinus sumatrensis) are anthropogenic. Although many disciplines are important for conservation, understanding the behaviour characteristics of a species should be considered a key component when developing wildlife-management and conservation strategies. A general overview of the behaviour of rhinoceros is presented, addressing ecology and social organization, activity and habitat use, feeding strategies, courtship and reproduction, and anti-predator behaviour. The implications of behavioural studies for successful management and husbandry of rhinoceros in captivity are discussed in sections on group size and composition, enclosure design and enrichment programmes, activity patterns, introductions, reproduction, hand-rearing, and health and stress. Finally, there is some discussion about the implications of this knowledge for in situ conservation in relation to designing protected areas, further aspects of animal health and stress, and reintroduction and translocation. A detailed understanding of rhinoceros behaviour is important for survival both in range-country protected areas and captivity, and such knowledge should be used to provide the most appropriate animal care and environments for these species. [source] Conservation programmes for African cattle: design, cost and benefitsJOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 2 2005S.B. Reist-Marti Summary Information on costs and benefits of conservation programmes for cattle is scarce in the literature and mainly available for Europe. This study aims at simulating cost of and benefits from different kinds of conservation programmes designed for indigenous African cattle. The programmes include installation of a herdbook and activities to promote the breed (HB), in situ conservation with a sire rotation scheme (IS), cryoconservation of semen (CC) and CC combined with in situ conservation (IC). The results indicate that cost of the analysed conservation programmes was generally higher than those reported in the literature for comparable schemes. If cost per effective population size conserved is considered, programmes analysed in this study do not appear to be more expensive. The proposed rotation scheme in IS can be applied to many different production systems and prove to be effective with regard to low increase in kinship. Reduction in extinction probability is found to be higher for conservation programmes that strongly involve farmers and give them part of the responsibility for the breeding population. IC was most efficient with regard to cost per effective population size conserved. However, if cost per reduction in endangerment is considered as criterion for the efficiency of a programme, IS, HB and CC are superior to IC. These findings suggest that decisions on conservation programmes should be based on multiple criteria, and not just on cost per effective population size. [source] ISSR Analysis of the Genetic Diversity of the Endangered Species Sinopodophyllum hexandrum (Royle) Ying from Western Sichuan Province, ChinaJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 10 2006Meng Xiao Abstract Sinopodophyllum hexandrum (Royle) Ying is an important medicinal and endangered species. Inter-simple sequence repeats (ISSR) analysis was conducted on seven natural populations from western Sichuan Province to investigate the genetic diversity of S. hexandrum. Leaf samples of 140 individuals were collected. Of the 139 discernible fragments generated by 12 selected primers (among 100 primers), 54 appeared to be polymorphic. The percentage of polymorphic bands (PPB) was 38.85% at the species level, and PPB within a population ranged from 7.91% to 23.74%. Low levels of genetic variation (He= 0.092, Ho= 0.142) and high levels of genetic differentiation among the populations (Gst= 62.25%) was detected on the basis of results from POPGENE and analysis of molecular variance (AMOVA), respectively. Furthermore, the limited gene flow (Nm= 0.361) may result from biological characteristics, such as self-pollination and short distance seed dispersal. Based on the genetic and ecological information available for S. hexandrum, we propose some appropriate strategies for the conservation of the endangered medicinal species in this region, namely rescuing and conserving the core populations for in situ conservation and sampling and preserving more populations with fewer individuals from each population for ex situ conservation. (Managing editor: Li-Hui Zhao) [source] Mating system and genetic diversity of a rare desert legume Ammopiptanthus nanus (Leguminosae)JOURNAL OF SYSTEMATICS EVOLUTION, Issue 1 2009Guo-Qing CHEN Abstract Ammopiptanthus nanus is an endangered evergreen shrub endemic to the deserts of central Asia and plays an important role in delaying further desertification. We examined allozyme variation and AFLP diversity in A. nanus populations and investigated the mating system of this species using progeny arrays assayed for polymorphic allozyme loci. Mating system analysis in the Keyi'eryongke'er population showed low levels of out-crossing, and strong inbreeding depression. Low levels of genetic variation were detected at both population (allozyme, Pp= 14.0%, A= 1.14, He= 0.031; AFLP, Pp= 14.5%, Shannon's information index I= 0.063) and species (allozyme, Pp= 21.1%, A= 1.21, He= 0.040; AFLP, Pp= 20.9%, I= 0.083) levels; while moderate genetic differentiation existed among populations, as indicated by allozymes (GST= 0.081) and AFLP (GST= 0.151,0.193). Founder effect, bottlenecks in evolutionary history, the mixed mating system and co-ancestry may have influenced the level of genetic diversity in A. nanus. Markers of both types provide new insights for conservation management, indicating that the Biao'ertuokuoyi and Keyi'eryongke'er populations should be given priority for in situ conservation and regarded as seed sources for ex situ conservation. [source] When North and South don't mix: genetic connectivity of a recently endangered oceanic cycad, Cycas micronesica, in Guam using EST-microsatellitesMOLECULAR ECOLOGY, Issue 12 2010ANGÉLICA CIBRIÁN-JARAMILLO Abstract Subject to environmental changes and recurrent isolation in the last ca. 250 Ma, cycads are often described as relicts of a previously common lineage, with populations characterized by low genetic variation and restricted gene flow. We found that on the island of Guam, the endemic Cycas micronesica has most of the genetic variation of 14 EST-microsatellites distributed within each of 18 genetic populations, from 24 original sampling sites. There were high levels of genetic variation in terms of total number of alleles and private alleles, and moderate levels of inbreeding. Restricted but ongoing gene flow among populations within Guam reveals a genetic mosaic, probably more typical of cycads than previously assumed. Contiguous cycad populations in the north of Guam had higher self-recruitment rates compared to fragmented populations in the south, with no substantial connection between them except for one population. Guam's genetic mosaic may be explained by the influence of forest continuity, seed size, edaphic differences, and human transport of cycads. Also important are the extent of synchrony among flushes of reproductive female seed-bearing sporophylls and restricted pollen movement by an obligate mutualist and generalist insects. An NADH EST-locus under positive selection may reflect pressure from edaphic differences across Guam. This and three other loci are ideal candidates for ecological genomic studies. Given this species' vulnerability due to the recent introduction of the cycad aulacaspis scale, we also identify priority populations for ex situ conservation, and provide a genetic baseline for understanding the effects of invasive species on cycads in the Western Pacific, and islands in general. [source] Population genetic structure of mahogany (Swietenia macrophylla King, Meliaceae) across the Brazilian Amazon, based on variation at microsatellite loci: implications for conservationMOLECULAR ECOLOGY, Issue 11 2003Maristerra R. Lemes Abstract Mahogany (Swietenia macrophylla, Meliaceae) is the most valuable and intensively exploited Neotropical tree. No information is available regarding the genetic structure of mahogany in South America, yet the region harbours most of the unlogged populations of this prized hardwood. Here we report on the genetic diversity within and the differentiation among seven natural populations separated by up to 2100 km along the southern arc of the Brazilian Amazon basin. We analysed the variation at eight microsatellite loci for 194 adult individuals. All loci were highly variable, with the number of alleles per locus ranging from 13 to 27 (mean = 18.4). High levels of genetic diversity were found for all populations at the eight loci (mean HE = 0.781, range 0.754,0.812). We found moderate but statistically significant genetic differentiation among populations considering both estimators of FST and RST, , = 0.097 and , = 0.147, respectively. Estimates of , and , were significantly greater than zero for all pairwise population comparisons. Pairwise ,-values were positively and significantly correlated with geographical distance under the isolation-by-distance model. Furthermore, four of the populations exhibited a significant inbreeding coefficient. The finding of local differentiation among Amazonian mahogany populations underscores the need for in situ conservation of multiple populations of S. macrophylla across its distribution in the Brazilian Amazon. In addition, the occurrence of microgeographical genetic differentiation at a local scale indicates the importance of maintaining populations in their diverse habitats, especially in areas with mosaics of topography and soil. [source] Square pegs in round holes , the implications of shell shape variation on the translocation of adult Margaritifera margaritifera (L.)AQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 5 2010S. J. Preston Abstract 1.The freshwater pearl mussel Margaritifera margaritifera is endangered throughout Europe. 2.Historically, mussels were described on the basis of shell characteristics. In more recent years with the advent of molecular techniques many ,species' of molluscs have been found to be ecophenotypes. 3.The pearl mussel is found in numerous rivers throughout Ireland and the UK with varying degrees of superficial differences. It is has been thought that the most divergent form is found in the Nore River, Ireland, Margaritifera m. durrovensis. 4.The current investigation considers shell shape differences (using morphometrics , elliptic Fourier descriptors) in mussels from a variety of rivers in Ireland in relation to river pH. 5.Results suggest that M. margaritifera has a fairly plastic phenotype, with a gradient of shape change in relation to water pH. 6.Margaritifera m. durrovensis does not appear to be morphologically unique from other populations studied, instead occurring at one end of the shell shape gradient. 7.Findings also suggest that shell shape may be characteristic to individual rivers. The existence of phenotypically distinct groups of Margaritifera margaritifera has particularly important implications for the future conservation of the species. 8.Ex situ conservation and reintroduction efforts will need to consider both the genotypic and phenotypic suitability of mussels if translocation is to be used as a viable conservation tool in the future. Copyright © 2010 John Wiley & Sons, Ltd. [source] Fluctuaciones Temporales en la Composición Floristica del Bosque Tropical Atlántico,BIOTROPICA, Issue 1 2001Samir Gonçalves Rolim ABSTRACT Temporal and spatial changes in floristic composition over a 15-year period in an Atlantic tropical forest in Brazil were analyzed. The data were recorded in five 0.5-ha (50 × 100 m) plots within a 22,000-ha forest reserve. In each plot, all stems ± 10 cm diameter at breast height (DBH) were repeatedly inventoried. The overall number of species among all plots was steady over time but changed within a given plot. In all plots, the proportion for the disappearance of species was 7 percent and that for immigration of new species into the plots was 9.5 percent. Approximately 65 percent of the disappearance occurred between 1986 and 1989, and 74 percent of the immigration happened after 1986. The observed changes in composition evidently were due to natural disturbance and climatic events, such as an unusual four-month drought. Disappearance of species from the plots did not denote regional extinction of those species, because they persisted elsewhere in the forest reserve. The changes in species composition within the plots and persistence outside them, however, indicated that large areas are required for in situ conservation of tropical tree species. These areas must be large enough for population changes to occur without negative effects on genetic and demographic structures of tree species. RESUMES Foram analisadas as variações temporais e espaciais na composição florística de uma floresta tropical num período de 15 anos entre os anos de 1980 e 1995. Em 5 parcelas de 0.5 ha (50 × 100 m) amostraram-se todas as árvores com diàmetro a altura do peito (DAP) , 10 cm. Para a escala e período que este estudo abrangeu pode-se concluir que há uma estabilidade no número de espécies da comunidade ao longo do tempo e esta estabilidade foi significativamente afetada por um distúrbio natural (um período seco de 4 meses) ocorrido em 1987. Foi constatado que em 15 anos desapareceram 7 por ciento das espécies nas parcelas monitoradas, contra um total de 9.5 por ciento de novas espécies recrutadas. Aproximadamente 65 por ciento do desaparecimento de espécies ocorreu entre 1986 e 1989 e 74 por ciento das novas espécies foram recrutadas apos 1986. O desaparecimento não significa necessariatmente um fenômeno de extinção e foi demonstrado que as espécies continuam ocorrendo na comunidade. O desaparecimento de espécies dentro das parcelas e sua pcrsisténcia fora delas indica que são necessárias grandes áreas para conservação in situ de espécies arbóreas. Estas áreas devem ser capazes de absorver as flutuaçz,oes populacionais sem afetar a estrutura genética e demográfica das espécies. [source] | ||||||||||||||||||||||