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1.
While the Caribbean is a recognized “biodiversity hotspot”, plant conservation has not received adequate attention; particularly, given the high levels of endemism in many plant groups. Besides establishing protected areas, there needs to be a sustained effort to study the taxonomy, systematics and ecology of the flora. Recent phylogenetic studies have shown high levels of endemism and conservation studies indicate a large propotion of the flora is threatened with extinction. Eight recommendations are given for plant conservation in the region.  相似文献   

2.
湖北后河自然保护区拥有丰富的生物多样性,为中国生物多样性三大关键地区之一的川东-湘鄂西关键地区的重要组成部分。但所处的贫困山区少数民族县长期以来以森工产业为其县域经济的主要支柱,长期的木材采伐和狩猎习俗曾对该保护区的生物多样性带来了严重破坏。自然保护区的建立使其生物多样性逐渐得到了有效保护,特别是升为国家级自然保护区后,生物多样性保护进入了一个新阶段。但该保护区的生物多样性依然面临多种威胁,保护区自身科学研究力量的薄弱和保护区面积相对较小,限制着该区域生物多样性的进一步研究和保护。进一步扩充保护区面积、引进科研力量并提升自身人员科研素质、协调并增强区内外社区共管是该区生物多样性得到进一步保护和恢复的当务之急。  相似文献   

3.
Summary Fencing incentive programmes have been widely used throughout Australia to assist landholders to fence remnant woodland vegetation, to control grazing and improve native vegetation condition. This study investigated vegetation and soil condition in remnant woodlands fenced for 7–9 years in the Murray catchment area in southern New South Wales. Surveys were undertaken at 42 sites, where vegetation condition was assessed in paired fenced and unfenced sites. Semi‐structured interviews were also conducted with landholders to gather management information. Woodlands surveyed were Yellow Box/Blakely's Red Gum (Eucalyptus melliodora/E. blakelyi, 15 sites), Grey Box (E. microcarpa, 13 sites) and White Cypress Pine (Callitris glaucophylla, 14 sites). Fencing resulted in a range of responses which were highly variable between sites and vegetation types. In general, fenced sites had greater tree regeneration, cover of native perennial grasses, less cover of exotic annual grasses and weeds, and less soil compaction than unfenced sites. However, there was greater tree recruitment in remnants to the west of the study area, and tree recruitment was positively correlated with time since fencing. Within sites, tree recruitment tended to occur in more open areas with a good cover of native perennial grasses, as compared to sites with a dense tree canopy, or dominated by exotic annuals grasses or weeds. Forty‐eight per cent of fenced sites had no tree regeneration. There was a significant decline in native perennial grasses, and increase of several unpalatable weeds in many fenced areas, suggesting certain ecological barriers may be preventing further recovery. However, drought conditions and associated grazing are the most likely cause of this trend. A range of grazing strategies was implemented in fenced sites which require further research as a conservation management tool. Continued long‐term monitoring is essential to detect key threats to endangered woodland remnants.  相似文献   

4.
Resolving the conflicts between biodiversity conservation and socioeconomic development is a global pursuit for the long-run prospects of the human species. Based on Wenchuan County, a typical county in southwestern China, a group of 20 indicators quantifying regional biodiversity and socioeconomic development was established to classify and evaluate the county area spatially. A fuzzy c-means clustering (FCM) algorithm was used as the classification method. Three indices including BD, DL and DR characterizing the value of biodiversity, the level and rate of socioeconomic development of the delineated regions were formulated. The results indicated that Wenchuan County was optimally classified into 4 types of regions (region I to IV). The area percentages of the regions vary widely from 4.3 to 65.7%. The sequences of the regions on biodiversity, socioeconomic development level, and socioeconomic development rate were, respectively, IV > II > III > I, I > III > II > IV and III >I >II >IV. The spatial strategy on coordinating biodiversity conservation and regional development is to develop mainly from the east(I, II, III) and to conserve mainly in the west(IV). Eco-industry, such as eco-tourism and eco-agriculture, need to be emphasized in the process of regional development. The quantitative methods used here may have a wide applicability.  相似文献   

5.
The High Weald is an unusually well-wooded area in southern England. A high proportion of this woodland is ancient, being formerly exploited as seasonal pasture and coppice. Multiple pollen profiles from the Rye area have been used to elucidate the origins of this cultural landscape. By combining sites with small and large pollen source areas, both local and regional patterns of vegetation change have been determined. The mid-Holocene Tilia-dominated woodlands were subjected to temporary clearance as early as the Neolithic. This woodland was more extensively exploited over a ca. 700 year period from the beginning of the Bronze Age. The main elements of the modern landscape (woodland, pasture and limited cultivation) can be traced back to a more intensive phase of human activity, which commenced in the late Bronze Age. A regional increase in Fagus sylvatica pollen ca. 750 B.C. probably reflects the use of the Wealden woods for pasturage. There is no palynological evidence that the fuel demands of the Roman iron industry resulted in widespread woodland destruction. The early Anglo-Saxon period appears to have been one of land-use continuity, with a second increase in Fagus pollen at ca. A.D. 700 corresponding to historical evidence for the presence of wood-pastures in the Weald.  相似文献   

6.
Data are presented on the identification and characterisation of 17 chromosomal integration loci of the insertion element IS901 in the Mycobacterium avium (cervine strain JD88/118) genome. Thirteen of these integration loci have been mapped to their corresponding positions on the M. avium strain 104 (an IS901(-) strain) genome (The Institute for Genome Research (TIGR) unfinished genome-sequencing project). Sequence data for both upstream and downstream sequence flanking regions were obtained for 12 insertion loci, while upstream sequence was obtained for five others. A consensus IS901 insertion target sequence compiled from all 17 integration sites was in broad agreement with earlier reports that were based on only two such loci. Analysis of IS901 integration site flanking sequences revealed that, like IS900 in M. avium subspecies paratuberculosis, IS901 inserts preferentially between a putative ribosome-binding sequence (RBS) and the translational start codon of an open reading frame (ORF). In BLAST X and BLAST P searches of the GenBank database, these ORFs were shown to share significant homologies with a number of other prokaryotic genes.  相似文献   

7.
The Cape Peninsula is an area of outstanding natural beauty and exceptional biodiversity, worthy of proclamation as a World Heritage Site. The area is dominated by fynbos vegetation, usually managed by means of prescribed burning, together with various programmes aimed at the control of invasive alien plant species. Effective management of the Peninsula is bedevilled by the fact that the area is controlled by no less than 14 different public bodies, resulting in fragmentation of effort and the lack of a standardized approach to management. Historically, many official and unofficial investigations have called for this problem to be resolved, without success. The lack of coherent, focused, and well funded fire and alien weed control management plans for the entire Peninsula is a serious deficiency. Despite this, considerable progress has been made towards the establishment of a database for the Peninsula, and the development of decision support systems that can utilize this database for rational management. Adoption of such a system would provide a powerful uniting tramework that would standardize and influence the management approaches adopted by the various controlling authorities.  相似文献   

8.
Worldwide, tropical landscapes are increasingly dominated by human land use systems and natural forest cover is decreasing rapidly. We studied frugivorous butterflies and several vegetation parameters in 24 sampling stations distributed over near-primary forest (NF), secondary forest (SF), agroforestry and annual culture sites in the Northeastern part of the Korup region, SW Cameroon. As in other studies, both butterfly species richness and abundance were significantly affected by habitat modification. Butterfly richness and abundance were highest in SF and agroforestry sites and significantly lower in NF and annual crop sites. Butterfly species richness increased significantly with increasing tree density, but seemed to decrease with increasing herb diversity and density in annual crop farms. A significant negative correlation was found between butterfly geographic range and their preference for NF sites. Our results also showed that agroforestry systems, containing remnants of natural forest, can help to sustain high site richness, but appear to have low complementarity through loss of endemic species confined to more undisturbed habitats. Our study also indicated that the abundance of selected restricted-range butterflies, particularly in the family Nymphalidae, appears to be a good indicator to assess and monitor forest disturbance.  相似文献   

9.
Mount Kawa Karpo of the Menri ('Medicine Mountains' in Tibetan), in the eastern Himalayas, is one of the most sacred mountains to Tibetan Buddhists. Numerous sacred sites are found between 1900 and 4000 m, and at higher elevations the area as a whole is considered a sacred landscape. Religious beliefs may affect the ecology of these sacred areas, resulting in unique ecological characteristics of importance to conservation; recent studies have demonstrated that sacred areas can often play a major role in conservation. The goal of this study is to preliminarily analyze the vegetation of sacred areas in the Menri region using existing vegetation maps and a Geographical Information System (GIS) for remote assessment. Sacred sites are compared to random points in the landscape, in terms of: elevation, vegetation, and nearness to villages; species composition, diversity, and richness; and frequency of useful and endemic plant species. Detrended correspondence analysis (DCA) ordination reveals that sacred sites differ significantly in both useful species composition (p=0.034) and endemic species composition (p=0.045). Sacred sites are located at lower elevations, and closer to villages, than randomly selected, non-sacred sites (p< 0.0001), and have higher overall species richness (p=0.033) and diversity (p=0.042). In addition, the high-elevation (> 4000 m) areas of the mountain - a sacred landscape - are found to have significantly more endemics than low-elevation areas (p<0.0001). These findings represent an initial analysis of sacred sites and suggest that sacred sites in the Menri region may be ecologically and ethnobotanically unique.  相似文献   

10.
Methods for establishing biodiversity conservation priorities are urgently required, as the number of species and habitats that are threatened increases relative to the material resources available for their conservation. The identification of priority areas demands the integration of biophysical data on ecosystems together with social data on human pressures and planning opportunities. But comprehensive and reliable data are rarely available to demarcate where the need for action is most urgent and where the benefits of conservation strategies can be maximized. Strategic conservation initiatives cannot wait for the creation of comprehensive databases. In order to fill the missing data gaps, the combined knowledge of local and technical experts can be used. This study presents a collaborative geographic information system (GIS) method for integrating the knowledge of local and technical experts with existing spatial environmental data to establish priority areas for biodiversity conservation. Procedures for structuring and framing the discussions, establishing assessment criteria, integrating knowledge with data, and building consensus are incorporated into the method. The method provides a novel cooperative mechanism to aid spatial knowledge management and inclusive biodiversity planning.  相似文献   

11.
Lessons from the past: forests and biodiversity   总被引:2,自引:0,他引:2  
The biodiversity of forested regions today is the result of complex historical interactions among physical, biological, and social forces over time, often heavily influenced by cycles of various sorts. Fire, agriculture technology, and trade have been particularly powerful human influences on forests. Virtually all of our planet's forests have been affected by the cultural patterns of human use, and the resulting landscape is an ever-changing mosaic of unmanaged and managed patches of habitat, which vary in size, shape, and arrangement. Because chance factors, human influence and small climatic variation can cause very substantial changes in vegetation, the biodiversity for any given landscape will vary substantially over any significant time period- and no one variant is necessarily more natural than the others. This implies that biodiversity conservation efforts may need to give greater attention to ecosystem processes than to ecosystem products. A review of historical evidence shows that past civilizations have tended to over-exploit their forests, and that such abuse of important resources has been a significant factor in the decline of the over-exploiting society. It appears that the best way to maintain biodiversity in forest ecosystems in the late 20th Century is through a combination of strictly protected areas (carefully selected on the basis of clearly defined criteria), multiple-use areas managed by local people, natural forests extensively managed for sustainable yield of logs and other products and services, and forest plantations intensively managed for the wood products needed by society. This diversity of approaches and uses will provide humanity with the widest range of options, the greatest diversity of opportunities, for adapting to the cyclical changes which are certain to continue.  相似文献   

12.
With diversification of field type among households in same eco-environment and social situation, even in the same ecosystem, merging household socio-economics with biodiversity initiative values to determine incentives and optimum strategy of on-farm conservation of biodiversity. Botany survey of agroecosystems at landscape level in Daka and Baka, Xishuangbanna, Yunnan, China, as well as household differentiation of biodiversity in agroecosystem and on-farm conservation strategy merging household socio-economic characters were studied. There were 73 families 179 species distributed in 0.1 ha of different agroecosystems in Daka, and 70 families 166 species distributed in 0.08 ha different agroecosystems of Baka respectively. The cosmopolitan families, such as Gramineae and Compositae decreased the percentage of tropical families and subtropical families. Botany survey among 12 random selected households from Daka in 46 sampling plots of different agroecosystems showed significant differentiation of the species richness indices of natural biodiversity and agrobiodiversity as there were differences of cognition and utilization of plant species besides management practices among households. Dengrogram using the Ward method of hierarchical cluster analysis based on annual questionnaire interview of 60% household from 1998 to 2001 in Daka showed disparity among different households’ socio-economics which underpins management diversity. There were significant correlation coefficients between household socio-economics and species richness indices of different agroecosystems. Fallow size had significant positive correlation coefficients with species richness index of rubber plantation. By contraries, production input had negative correlation coefficients with species richness index of upland rice field. Meanwhile, cereal crop income had significant positive correlation coefficient with agro-species richness index of rubber plantation. By contraries, other income such as off-farm income had negative correlation coefficients with agro-species richness index of rubber plantation. Innovations of the expert farmer on agrobiodiversity on farm conservation were admiration.  相似文献   

13.
Summary

The paper explores whether any of the familar range of current oakwood structures in the west of Scotland can be used as realistic analogues for the prehistoric oakwoods. Even for the early historic oak woodlands we have no detailed knowledge of previous structures and composition.

The structure of today's oak woodlands, and to some extent even the legacy of species within that habitat, are a type of biocultural heritage. The oak woodlands that we see today are the product of a long interaction: between man's use of the woodlands and the ongoing natural processes within the oakwood ecosystem.

Grazing animals, especially domestic cattle and red deer, have played a key part in determining oak woodland structure in historic times, and perhaps have a future role too. Are there lessons to be drawn from knowledge of past management and regeneration of oak which are relevant to the present day, when most managers are finding it difficult to regenerate oak woodlands on any scale?

Understanding past utilisation and structure of oak woodlands is valuable mainly as a guide to future management. Indeed one might ask which models and structures are relevant for managing an oak woodland resource now regarded mainly as a wildlife habitat?  相似文献   

14.
The land market in part of New South Wales, Australia, has been shown to conserve the soil and promote sustainable agriculture. The market incentive at work is the availability of information on the erosion status of the land. This paper explores the general possibility that provision of market information on environmental characteristics will lead to improvements in environmental quality. In this way the market would encourage landowners to conserve their land, retain native vegetation, improve biodiversity and pursue sustainable agriculture. They would do all this automatically, without government regulations, bans or moratoria, and without a new government agency or new act to implement the policy. The government officers would merely show buyers and sellers in the land market where to obtain, and how to use, the relevant information.  相似文献   

15.
The monitoring of biodiversity at the level of habitats is becoming widespread in Europe and elsewhere as countries establish national habitat monitoring systems and various organisations initiate regional and local schemes. Parallel to this growth, it is increasingly important to address biodiversity changes on large spatial (e.g. continental) and temporal (e.g. decade-long) scales, which requires the integration of currently ongoing monitoring efforts. Here we review habitat monitoring and develop a framework for integrating data or activities across habitat monitoring schemes. We first identify three basic properties of monitoring activities: spatial aspect (explicitly spatial vs. non-spatial), documentation of spatial variation (field mapping vs. remote sensing) and coverage of habitats (all habitats or specific habitats in an area), and six classes of monitoring schemes based on these properties. Then we explore tasks essential for integrating schemes both within and across the major classes. Finally, we evaluate the need and potential for integration of currently existing schemes by drawing on data collected on European habitat monitoring in the EuMon project. Our results suggest a dire need for integration if we are to measure biodiversity changes across large spatial and temporal scales regarding the 2010 target and beyond. We also make recommendations for an integrated pan-European habitat monitoring scheme. Such a scheme should be based on remote sensing to record changes in land cover and habitat types over large scales, with complementary field mapping using unified methodology to provide ground truthing and to monitor small-scale changes, at least in habitat types of conservation importance.  相似文献   

16.
Summary Isolation and identification of a thermotolerant feather-degrading bacterial strain from Thai soil as well as purification and properties of its keratinase were investigated. The thermotolerant bacterium was identified as Bacillus licheniformis. The keratinase was purified to homogeneity by three-step chromatography. The purified enzyme exhibited a high specific activity (218 U mg−1) with 86-fold purification and 25% yield. The enzyme was monomeric and had a molecular mass of 35 kDa. The optimum pH and temperature for the enzyme were 8.5 and 60 °C, respectively. The enzyme activity was significantly inhibited by PMSF and partly inhibited by EDTA and iodoacetamide, but was stimulated by metal ions. It hydrolysed soluble proteins with a relative activity of 4–100% and insoluble proteins, including keratins, with a relative activity of 3–35%. Therefore, the enzyme could improve the nutritional value of meat- and poultry-processing wastes containing keratins, collagen and gelatin.  相似文献   

17.
To ensure the long-term future of NATURA 2000 sites across Europe, effective techniques are required for evaluating and monitoring their conservation significance. This paper describes a GIS-based method that uses multi-criteria evaluation (MCE) to determine the conservation significance of vegetation communities and habitats for a case study of a proposed NATURA 2000 site on the northwest coast of Crete, Greece. The method uses the most frequently used criteria for the selection of priority areas for nature conservation—species and habitat diversity, rarity of species and habitats, naturalness, threat of human disturbance and replaceability. For each community and corresponding habitat type, each criterion was scored according to field data and expert knowledge using a numerical scale. The final conservation score for each community was derived using MCE within a GIS and mapped. The results demonstrated that the method is an effective tool for evaluating and comparing conservation significance and could be applied to other sites across Europe and to monitor change.  相似文献   

18.
The conservation status of all the amphibians in China is analyzed, and the country is shown to be a global priority for conservation in comparison to many other countries of the world. Three Chinese regions are particularly rich in amphibian diversity: Hengduan, Nanling, and Wuyi mountains. Salamanders are more threatened than frogs and toads. Several smaller families show a high propensity to become seriously threatened: Bombinatoridae, Cryptobranchidae, Hynobiidae and Salamandridae. Like other parts of the world, stream-breeding, high-elevation forest amphibians have a much higher likelihood of being seriously threatened. Habitat loss, pollution, and over-harvesting are the most serious threats to Chinese amphibians. Over-harvesting is a less pervasive threat than habitat loss, but it is more likely to drive a species into rapid decline. Five conservation challenges are mentioned with recommendations for the highest priority research and conservation actions.  相似文献   

19.
Some morphological and physiological characteristics of an Isaria fumosorosea isolate with diminished virulence, IFCF01-D, and its parent isolate, IFCF01, were evaluated and laboratory bioassays were performed to assess their virulence against Plutella xylostella. The relationship among these traits and virulence against P. xylostella is discussed. There were no significant differences in conidial viability, spore production and the time required for 50% germination (GT50). Spore viability after incubation for 24 h at 25°C was greater than 98% for both isolates tested. Spore production on potato dextrose agar after 14 days incubation at 25°C was 4.68 × 108 and 4.59 × 108 conidia/mL for IFCF01 and IFCF01-D, respectively. When exposed to high temperatures (40, 45, 50 or 55°C) through a water bath for 10 min, conidial germination ranged from 0.83% to 84.0% for IFCF01 and 0% to 86% for IFCF01-D. Germination rate showed a negative relationship with the exposure temperature for both isolates. The per cent germination of isolate IFCF01 24 h after ultraviolet (UV) radiation (18 W, 240–260 nm) varied from 0% to 92% and 0% to 81% for IFCF01-D. Germination rate and the exposure time exhibited a negative correlation for both isolates tested. Conidial surface hydrophobicity of IFCF01 (60%) was significantly higher than that of isolate IFCF01-D (53%). Subsequently, using the cicada exuviae as the substrate for enzymatic analysis, Pr1 and chitinase activity demonstrated the contrasting virulence traits: higher specific activities for the more virulent IFCF01 and lower enzymatic levels for isolate IFCF01-D.  相似文献   

20.
This paper addresses three major issues. Firstly, molecular taxonomy and its application to elucidate the biodiversity and biogeography of entomopathogenic nematodes is considered. Accurate identification is fundamental for understanding biodiversity, and because these nematodes are morphologically conservative, molecular techniques will provide the insights necessary to develop a robust, morphologically based taxonomy. Secondly, a review of the knowledge on their biogeography and habitat specificity, including a consideration of the limitations to the available data is given. Much of the information is presented in two tables which summarize the distributions of recognized species at continental and national levels. Thirdly, this paper provides a brief consideration of the Convention on Biological Diversity and its implications for future work with entomopathogenic nematodes and biological control.  相似文献   

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