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1.
Crop wild relatives (CWR) and wild harvested plant species (WHP) constitute an important element of a nation’s plant genetic resources (PGR) available for utilisation. Although their natural populations are threatened like other wild species by habitat lost and fragmentation, little attention has generally been paid to their systematic conservation. The development of checklists and inventories is considered by the convention on biological diversity (CBD) and the global strategy for plant conservation (GSPC) as the first step in any national strategy for conservation and sustainable use of plant diversity. Methodological approaches to the development of a national inventory of wild PGR are discussed in the light of a case-study for the CWR and WHP growing in mainland Portugal. The resultant inventory comprises 2319 taxa, of which 97.5% are CWR, 21.4% are WHP and 19.0% are both CWR and WHP. Approximately 6.1% are endemic to mainland Portugal; 24.1% occur in 1 to 4 Portuguese administrative regions; 15.6% are threatened, but only 5.9% are covered by legislative protection. Taxonomic misalignments and the dispersed nature of biological literature were the major impediments to the production of the national inventory, but once the inventory was established it has proven to be a powerful tool in conservation management.  相似文献   

2.
To conserve a rare plant, conservation programs must be guided by the biological attributes of the species. What constitutes the most critical biological information for plant conservation has been the issue of discussion for the last 30 years. Most scientists promote an approach that is either ecological or genetic in emphasis. Ecological and genetic processes will often interact synergistically to influence the population viability and to determine the persistence of populations in the long run. Consequently, conservation management of plant species, in addition to ecological information, requires a robust understanding of underlying genetic processes as well as the variation within and between populations. Conservation has a cost and the resources available for conservation programs are always limited. Therefore, conservation management strategies should not only be scientifically justified but also practical in terms of resource availability. Shorea lumutensis is a rare and endemic dipterocarp in Peninsular Malaysia. A comprehensive research activity was initiated to assess the population ecology and population genetics of S. lumutensis to elucidate specific ecological and genetic requirements and subsequently to set conservation strategies and priorities. This paper is apparently the first attempt at applying both the ecological and genetic approaches into conservation management of a rare dipterocarp. In addition, this paper also attempts to link the gaps between conservation research and conservation management in a realistic manner. It is our hope that this study will serve as a model for the study of other rare dipterocarps which should be given priority for conservation.  相似文献   

3.
The Convention on Biological Diversity and the subsequent International Treaty on Plant Genetic Resources for Food and Agriculture have proved a watershed in plant genetic resources (PGR) conservation and consequent initiatives have set various PGR conservation targets to be met by 2010. The aim of our paper is to develop ideas and issues concerning the monitoring of natural genetic resources: particularly in terms of developing a baseline from which to measure levels of genetic diversity. Three species of Brassica (B. nigra, B. oleracea, B. rapa) found wild in the UK were assessed for levels of genetic diversity using AFLP. The relationship between genetic distribution and ecogeographic distribution was considered for each species to determine patterns that may be useful in formulating conservation strategies. Genetic distance between populations of B. nigra and B. rapa were correlated to geographic distance. Levels of genetic polymorphism in B. oleracea were correlated to soil pH while in B. rapa they were correlated to soil coarseness. In terms of PGR conservation these findings may suggest an emphasis toward in situ conservation of a selection of disparate populations would be appropriate where possible as such adaptations may be lost in ex situ collections.  相似文献   

4.
Effective conservation strategies aimed to protect crop genetic resources require multiple sources of information. We used a combination of AFLP genotyping and farmer surveys to understand the extent, distribution and management of tartary buckwheat (Fagopyrum tataricum Gaertn.) diversity in its center of origin in Yunnan Province, China. We found genetic evidence of gene flow in tartary buckwheat throughout the study area, with small but statistically significant regional and village-level components. We also found genetic differentiation by seed color. Although most farmers reported exchanging seed in localized kinship networks, our results imply homogenizing gene flow is occurring. Yi ethnic farmers tend to plant more buckwheat than non-Yi farmers, and we found that in some communities, Yi farmers serve as seed sources for farmers of other ethnicities. Different tartary buckwheat varieties did not have different end uses; rather farmers maintained varietal diversity in order to protect crop yield and quality. Individual farmers’ seed exchange practices reflect their ideas about components of seed quality, as well as priorities in protecting buckwheat yield. From the standpoint of genetic resources conservation, the presence of a culturally rich farmer exchange network and hierarchical structuring of tartary buckwheat genetic diversity demonstrates the importance of maintaining an interlinked community of tartary buckwheat farmers in Yunnan.  相似文献   

5.
Site selection, reserve selection, and spatial conservation prioritization are terms that have been used for various algorithms and methods for the spatial allocation of conservation resources. Many of these methods start from the setting of targets or weights for different conservation features. Almost always there is only one set of targets or weights, thus implicitly assuming that priorities stay the same through the entire planning region. However, priorities for biodiversity governance could vary between regions. For example, priorities inside countries could be different from global priorities. Inside a country, different stakeholders could hold different priorities. Thus, priorities could vary between sub-regions while ecological processes, such as connectivity, cross borders without regard to administrative boundaries. Here we describe how it is possible to account for conservation priorities that vary between administrative sub-regions in conservation prioritization. We illustrate how assumptions about selection methods and feature weights can significantly influence the outcome mapping of conservation priority. We also show how placing high emphasis on local considerations reduces the cost-efficiency of the global conservation outcome. Analyses proposed here will be made publicly available in software (Zonation) capable for large-scale high-resolution conservation prioritization.  相似文献   

6.
An understanding of the genetic structure of populations is vital for the formation of optimum collection, conservation and utilization strategies for plant genetic resources. This is of particular importance in the case of in-situ conservation, a strategy gaining in popularity. The population genetic structures of five wild lentil taxa, Lens culinaris subsp. orientalis, L. odemensis, L. ervoides, L. nigricans and L. lamottei were investigated using isozyme electrophoresis and random amplified polymorphic DNA (RAPD). Approximately 20 plants from each of 5 populations per taxon were screened for variation at 11 isozyme loci and using three RAPD primers. Levels of variation were generally low, although considerable variation existed in the levels of diversity found within populations of L. culinaris subsp. orientalis and L. lamottei. Comparison of the results obtained in this study with the results obtained in a previous study indicate that this is a trend occurring across all species. It implies that levels of diversity within populations must be measured and considered prior to targeting of specific populations for in-situ conservation. Analysis of molecular variance of both isozyme and RAPD data revealed that between 78% and 99% of the variation was attributable to between-population differences. Isozyme results from L. lamottei populations were, however, contradictory. Possible explanations for this difference are discussed.  相似文献   

7.
8.
Towards a methodology for on-farm conservation of plant genetic resources   总被引:2,自引:2,他引:2  
The signing of the Convention on Biological Diversity at the ``Earth Summit' in 1992, its ratification and its subsequent entering into force have highlighted the need for an approach to biodiversity conservation that employs both ex situ and in situ techniques in a complementary manner. Though much research has focused on ex situ techniques, less progress has been made in developing methodologies for the conservation of genetic diversity in situ. The definition of in situ conservation used in the Convention on Biological Diversity encompasses two distinct processes: conservation of wild species in genetic reserves and of crops on-farm. Of these two, the latter, where the genetic diversity of crop land races is conserved within traditional farming systems, has been the less studied and remains less well understood. While there are still relatively few practical examples of on-farm genetic resources conservation, most genetic diversity of immediate and potential use to plant breeders is found among land races, and there is evidence that it is being rapidly eroded. This paper attempts to set on-farm conservation within the context of plant genetic resource conservation as a whole, to introduces a possible generalised model for the conservation of genetic diversity on-farm and to promote debate around the science of on-farm conservation.  相似文献   

9.
Natural hybridization between plant species often occurs in disturbed habitats and it is generally considered a threat for rare and endangered species. A different situation occurs in Mediterranean food deceptive orchids, where hybridization is a common phenomenon, as a natural consequence of their unspecific pollination system.Here, we present molecular and ecological evidence from a hybrid zone between Orchis mascula and O. pauciflora in order to address the consequences of hybridization on local orchid evolution and to assess conservation priorities for hybrids and hybrid zones in orchid conservation programs.We find that, although hybrids among the two target taxa are formed relatively frequently, hybrid zones often consist of F1 individuals, whereas backcrosses and later generation hybrids appear to be either rare or absent, presumably as a consequence of post-zygotic reproductive barriers acting in these food-deceptive orchids. Experimental evidence further indicates that hybrids are less fit than the parental species in attracting pollinators and that parental taxa exhibit higher or similar fitness in sympatry compared to allopatric populations. Since introgression is not frequent as indicated by molecular analyses, fitness and phenotypic trait differences observed among sympatric and allopatric populations of the parental taxa may be a consequence of pollinator-mediated selection.Our experimental data confirm that hybridization is a natural phenomenon in food-deceptive orchids and that it does not pose a threat to their survival. Furthermore, sympatric zones provide the stage for evolutionary processes in orchids, and this peculiarity should be taken into account when devising orchid conservation strategies.  相似文献   

10.
The conservation of biological diversity requires an integrated approach covering the ecological demands of a multitude of species. Integration may be achieved by focusing on a careful selection of target species, which is rare in practice. Calcareous grasslands offer a case in point. Although they harbour a high diversity of both plant and insect species, in management the emphasis is placed on the flora. This results in an underestimation of, notably, the importance of structural heterogeneity in the vegetation. As an apparent consequence, conservation management in the Netherlands has been much more successful for the flora than for butterflies. In contrast, Germany shows promising efforts to integrate both plant and animal species in conservation management and landscape planning. The main constraints for a successfully integrated conservation management presently consist of a limited availability and exchange of information, and an insufficient organisation of research and management at an international level.  相似文献   

11.
On-farm conservation of plant genetic resources for food and agriculture has received strong support worldwide in recent years. It has been justified on appealing assumptions: it complements ex situ conservation, allows co-evolutionary interaction of host–pathogens and crop–weed complexes, and involves local knowledge systems. This article illustrates how on-farm conservation being set for its sake is extremely difficult under farmers’ dynamic management of plant genetic resources based on sorghum. The dynamics of their management could be explained by continued introduction, displacement, loss and maintenance of aboriginal landraces that have distinct functional attributes, patch-occupancy and relative abundance profiles. Such management and hence the dynamic landrace demography has largely been triggered by co-evolving biophysical stresses, spatial and seasonal variations. The best viable alternative to support farmers’ management of genetic resources is to link conservation to crop improvement both to enhance on-farm genetic diversity and make the biophysical environment a comfortable home for the plant genotypes.  相似文献   

12.
Target-based spatial prioritization is the default approach in conservation resource allocation. Here, we clarify a poorly known feature of target-based spatial prioritization that may lead to an unbalanced allocation of resources between species or other biodiversity features. Highest per-species resources will be allocated to species occurring in costly and otherwise species-poor locations, whereas smallest per-species resources will be allocated to species that occur in species-rich locations at low-cost areas. Uncertainty in information about processes determining distributions of biodiversity features may lead to uncertainty in target setting. This can be a problem if unnecessarily high targets emerge to consume excessive resources thus detracting from other conservation action. Difficulties might be encountered in particular when there are many features, targets are given simultaneously to multiple different types of biodiversity features, or components of features, or when there are interactions or correlations between features. Consequently, we recommend that the costs of targets for individual features could be evaluated to screen for such targets that consume a disproportionate fraction of available resources. Costs of targets can be evaluated by a variant of the replacement cost technique. We also find that commonly used reserve selection methods, minimum set coverage, maximum coverage, and utility maximization differ significantly in how they treat targets and their costs.  相似文献   

13.
The integration of freshwater and terrestrial biodiversity priorities in systematic conservation planning is a major challenge to conservation planners. Maintaining upstream–downstream connectivity and the influence of catchments on freshwater ecological integrity are some of the issues that make it difficult to reconcile terrestrial and freshwater conservation planning. As a result most conservation assessments are often biased towards terrestrial systems without adequate incorporation of freshwater biodiversity in determining priority areas for conservation. In this paper, we propose a protocol for integrating the assessment of freshwater and terrestrial priorities in conservation planning, based on a case study from Mpumalanga Province in South Africa. The approach involves the separate assessment of freshwater priority areas, and using the outcome to influence the selection of terrestrial priority areas. This allowed both freshwater and terrestrial biodiversity to be incorporated in conservation planning without compromising their unique requirements. To test the effectiveness of this approach, we assessed percentage overlap between freshwater and terrestrial priority areas, target achievement, and the area required to achieve targets. We then compared the outcome from the proposed approach with the separate assessments of freshwater and terrestrial biodiversity priorities, and when both systems are given an equal weighting in a single assessment. The results showed that there was a noticeable improvement in the overlap of priority areas for freshwater and terrestrial biodiversity from 23% to 47%. Target achievement for freshwater biodiversity improved by 10% when terrestrial assessment was based on freshwater priority areas as opposed to terrestrial systems being assessed alone. There was negligible increase in area required, whether there was integration of freshwater and terrestrial biodiversity or no integration. We conclude that the most efficient way to achieve integration in conservation planning is to preferentially select areas where freshwater and terrestrial biodiversity priorities overlap.  相似文献   

14.
The north-eastern India is highly diverse in Citrus germplasm (23 taxa including their 68 varieties). The climate and soil factors are highly favourable for plant growth and fruit quality. Inspite of the high potentialities, the Citrus had remained more or less a family need based cultivated plant. The large variation in traditional agro-ecosystems of the region has evolved and preserved highly valuable genetic resources under different species. The value of certain taxa as rootstocks has been outlined. The conservation of germplasm and research gaps has been emphasised.  相似文献   

15.
European native plant diversity is currently suffering erosion and extinction and thus, it is crucial to improve conservation strategies to maintain this essential resource. If unchecked, this genetic erosion and species extinction will cause unnecessary and irreversible harm to the economy and social well being of Europe. Much plant biodiversity is undoubtedly found in the existing 9654 European protected areas that cover 1,066,358 km2, but clearly targeted and active conservation of priority plant species is required within these protected areas. To help ensure more efficient long-term sustainable conservation, a novel approach to the in situ conservation of European plants, notably crop wild relatives, is suggested. The purpose of this approach is to know what plant genetic resources (PGR) we have, where they are located and to assess whether the current network of protected areas includes a representative sample of European PGR diversity. The generation of in situ conservation and management plans for PGR populations in existing protected areas can significantly improve the present conservation status. Additionally, the identification of gaps of certain PGR in current protected areas can provide the basis for the designation of new complementary PGR in situ reserves.  相似文献   

16.
The need to prioritize species based on their perceived endangerment has led to the development of systems for categorizing and assessing their degree of vulnerability. Systems with divergent biological and geographical scopes can result in conflicting lists of high-priority species, potentially confusing conservationists and hampering the efficient allocation of resources. To assess conservation priorities for North American birds, we compare three priority-setting systems; those of the International Union for the Conservation of Nature (IUCN), NatureServe, and Partners in Flight (PIF). We found highest correspondence among the three systems in the highest and lowest categories of the respective systems with lower levels of correspondence in intermediate categories. We suggest that this is because the systems, while using different formulations of criteria, are based on the major factors known to be correlated with extinction risk. The few examples of species listed as a high conservation priority by one group but not one or both of the others appear to be the result of differences in availability or interpretation of data. Better communication and collaboration among those responsible for compiling the priority lists for each system is needed.A primary difference among the systems was the total number of species identified as conservation priorities. IUCN identified the fewest species (47) and PIF the most (157). This difference is the result of differences in geographic and taxonomic scope of each system. However, when considered as the percent of the total number of taxa evaluated by each system, all systems identified approximately 20% of species as of conservation concern. To reconcile disparate lists, we urge that conservationists use a hierarchical approach that first considers species that meet thresholds for endangerment under global systems, followed by species considered most vulnerable relative to all continental biota.  相似文献   

17.
Moringa oleifera Lam., a medium sized tree species has gained importance due to its multipurpose usage and well adaptability to dry and hot climates of north-western plains, central India and dry regions of peninsular India. This species is reported in this paper for distribution of diversity and genetic resources value in different parts of the country. Information on diversification in use viz. regional importance has been included to broaden the scope for value addition, identification of potential value and use in plant genetic resource programmes.  相似文献   

18.
Clonally propagated crops exhibit great diversity and are integral components of global and regional food systems. At the same time, little is known about the mechanisms that generate diversity within clonal crop species, and this diversity is increasingly threatened by economic, environmental, and social change. Research addressing the genetic basis for folk classification of clonal crops can address both of these challenges. Here, we carry out such research through a case study of the Andean tuber crop, oca (Oxalis tuberosa Molina). We employ ethnobotanical and molecular genetic methods to assess the congruence in partitioning of 216 oca accessions with respect to 26 folk taxa and with respect to 31 genetic clones. We find that the greatest number of folk taxa (11) correspond to single, unique genetic clones, but we also identify two instances of single folk taxa comprising multiple genetic clones and two instances of multiple folk taxa comprising single, shared genetic clones. We discuss the potential roles of different diversity-generating mechanisms, such as somaclonal variation and sexual reproduction, underlying these varied forms of congruence in order to inspire more directed research on this topic. We also discuss the implications of our findings on in situ and ex situ conservation work, in which practitioners often approximate crop genetic diversity by counting folk taxa. Ultimately, we argue that efforts to understand and conserve clonal crop diversity will be most effective when both folk classification and its genetic basis are considered together.  相似文献   

19.
The goal of habitat restoration is to provide environmental conditions that promote the maintenance and growth of target populations. But rarely is it considered how the allocation of resources influences the diversity of phenotypes in these populations. Here we present a framework for considering how habitat restoration can shape the development and expression of phenotypes. We call this approach phenotype management as it entails restoring the resources in a habitat to manage phenotypic diversity. Phenotype management is achieved by manipulating the spatial and temporal distribution of resources to alter the degree of competition among individuals. Differences in competition, in turn, lead to changes in phenotypic and life history expression that affect population parameters including demography and effective population size (Ne). To illustrate how phenotype management can be applied, we explore how resource distributions shape variation in phenotypes in two imperiled fishes, Pacific salmon and desert pupfish. In both examples, modulating male reproductive phenotypes changes the allocation of reproductive success among population members to subsequently affect Ne. These examples further demonstrate that whether to increase or decrease phenotypic diversity depends on the primary conservation pressures faced by the species.  相似文献   

20.
Limestone karsts on tropical land masses are considered de facto habitat islands due to their isolation from one another by non-calcareous substrata; this spatial configuration limits gene flow and induces high levels of species endemism. Apart from their biological importance, karsts are also highly valued for the ecosystem services and resources they provide if left intact. Unfortunately, conservation planning for karsts has generally lacked scientific basis. Ideally, factors affecting the richness and distribution of karst-endemic taxa should be incorporated into quantitative guidelines for karst reserve selection. Using land snail data from 43 different karstic towers in Malaysia, we: (1) identified biogeographical factors (i.e., area, isolation, surrounding soil type and geological age) hypothesized to influence endemic richness; and (2) investigated how species distributions varied among karsts in different regions. Generalized linear mixed-effect models revealed the relatively important effects of surrounding soil type and karst area on land snail endemism; the most parsimonious model contributed to 63.6% of the Akaike’s Information Criterion weight and explained over 18% of the deviance in karst-endemic richness (of which 10.0% was explained by surrounding soil type). Non-metric multi-dimensional scaling indicated that karsts in different regions of Malaysia had distinct malacofaunas. Therefore, conservation planners should take into account karst size, surrounding soil type and the influence of geographic barriers to maximize the protection of land snails and possibly other karst-endemic taxa, which are increasingly threatened by quarrying throughout Southeast Asia.  相似文献   

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