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1.
Quick biodiversity studies on poorly studied taxa and areas are increasingly popular for setting conservation priorities over a wide range of spatial scales. However, the implementation of such studies is complicated by the variable extent to which the different criteria used in prioritisation are correlated to each other. Using methods of constrained ordination, we examined the species-habitat relationships of carabid beetles based on ground beetle assemblages from 22 sites in the Picos de Europa National Park, northern Spain. We found characteristic species assemblages for subalpine meadows, Genista shrublands, and pastures, whereas mown meadows, heathlands, beech and riparian woodlands were occupied by more habitat generalist species. Species associated with subalpine meadows and Genista shrublands tended to be mostly brachypterous and to have geographic ranges restricted to northern Spain. In contrast, we found no relationship between the degree of species' association with pastures and geographic range-wing size type. Although the species richness was higher in riparian woodlands and mown meadows, we suggest a higher conservation value for subalpine meadows and Genista shrublands across the landscape because they sustain characteristic assemblages dominated by species with restricted ranges and reduced powers of dispersal. Our study suggests that preserving areas in the landscape supporting higher biodiversity will not necessarily preserve those species potentially more susceptible to habitat loss and fragmentation. It also supports the feasibility of biodiversity studies based on multivariate techniques for setting conservation priorities over complex landscapes.  相似文献   

2.
Feral pigs (Sus scrofa) have spread through Namadgi National Park (NNP) in south-eastern Australia since the early 1960s at a mean rate of 4 km/year. Pigs were abundant (approximately 1-2 pigs km−2) during the mid-1980s. Research from 1985 to 2000 inclusive has demonstrated a positive curved relationship across years between the frequency of occurrence of pig rooting and pig abundance (R2=0.48; P<0.001) and the extent of ground rooting; more pigs, more rooting. The ground rooting decreased plant species richness. There was a negative curved relationship between plant species richness and the extent of pig rooting at two sites (R2=0.81; P<0.0001 and R2=0.67; P<0.0001), with plant richness declining to zero with intensive pig rooting. Since the mid 1980s intensive pig control work has resulted in a significant (R2=0.39; P<0.001) decline in pig abundance with an annual instantaneous rate of change (r) of −0.15 between 1985 and 2000 inclusive. The results and their implications for biodiversity conservation and feral pig management are discussed.  相似文献   

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[目的] 三江源是“中华水塔”和中国重要生态安全屏障。探讨三江源国家公园土壤侵蚀分布规律,为实施生态保护政策及三江源国家公园水土保持与生态文明建设提供依据。[方法] 利用中国土壤流失方程(CSLE)、风力侵蚀模型和冻融侵蚀强度评价模型,采用叠加分析的方法,分析三江源国家公园土壤侵蚀状况及其在不同空间和下垫面的分布特征。[结果] 2020年公园土壤侵蚀面积2.64×104 km2,黄河源园区是土壤侵蚀分布最广泛的园区,而长江源园区土壤侵蚀相对严重;70%的水力侵蚀面积分布在地下冰发育带(海拔4 900 m以上),85%的风力侵蚀面积分布在地下冰发育带以下区域(海拔4 900 m以下),不同海拔高度区域土壤侵蚀及其分布差异显著;坡度5°及以下区域风力侵蚀面积比例达60%,是风力侵蚀相对集中分布区;水力侵蚀相对集中分布在8°~25°区域,水力侵蚀面积比例达75%,均是水土流失综合防治的重点区域;草地面积比例近80%,低覆盖、中低覆盖草地土壤侵蚀相对集中分布,沙地、裸土地的土壤侵蚀问题相对严重,值得重点关注。[结论] 三江源国家公园水力侵蚀主要分布在海拔4 900 m以上地下冰发育带,8°~35°的中低覆盖以下草地,占水力侵蚀面积的2/3左右;风力侵蚀主要集中分布在4 200~4 900 m,≤5°的中覆盖度以下草地。  相似文献   

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Bushmeat hunting is one of the primary threats to many large-bodied vertebrate species in African forests. However, species vary in their degree of vulnerability to hunting. We investigated the impact of hunting on monkey species in Cameroon’s Korup National Park (KNP) and examined how vulnerability to hunting varies among species. Data on primate abundance and hunting intensity were collected along 10 line transects, distributed across three survey areas in KNP. We assessed how the relative abundance of seven monkey species spatially varied between heavily and lightly hunted areas and evaluated temporal changes in the relative abundance and proportional representation of these species at a single hunted forest site and in bushmeat harvests. The putty-nosed and mona monkeys are most tolerant to heavy hunting pressure whereas the crowned monkey, drill, and red colobus are among the most vulnerable. At our heavily hunted survey site, the overall relative density of monkey groups increased through time but primate species richness declined. The proportional representation of Cercopithecus species, especially putty-nosed monkeys, increased through time, possibly due to competitive release. We also observed an increase in the proportional representation of the putty-nosed and mona monkeys and a reduced percent contribution of the red colobus and drill in hunter harvests. We conclude that hunting is driving some of Africa’s most threatened primate species (e.g., Preuss’s red colobus and the drill) to local extinction in KNP. We discuss intrinsic factors of species that might influence their degree of vulnerability and strategies to improve protection efforts in KNP.  相似文献   

7.
Emmer wheat, Triticum dicoccon Schrank was one of the founder crops of Neolithic agriculture. Though its cultivation was largely replaced by hexaploid wheats 2000 years ago, pockets of small scale cultivation can still be found. One such area is the Asturias region of Northern Spain, where emmer wheat remains a traditional crop for high value specialist culinary uses, and farmers grow locally adapted landraces. In order to study the diversity of these landraces, we sampled emmer wheat from different regions of Asturias, and genotyped multiple plants from each village using nuclear and chloroplast microsatellites. A high level of variation was observed with markers from both genomes, including a novel chloroplast haplotype. A strong geographic structure was observed in the Asturian emmer wheats in both the chloroplast markers and the nuclear microsatellite data.  相似文献   

8.
A study on contamination levels by organochlorinated compounds (pesticides and PCBs) and heavy metals (Hg, Cd, Pb, Cu and Zn) in Doñana National Park (Spain) area and its surrounding region has been carried out. Residue levels of xenobiotics were determined in water and soils samples from seventeen sites selected through the park and nearest surrounding farm lands affecting to the inner Park. Also we analyzed some stations along the Guadiamar Basin in the north of Doñana region to determined the movement and influence of one mine situated over 40 km away, in Aznalcóllar, where the commercial expoitation of pyrites ores rich in Zn, Pb and Cu is being operated.  相似文献   

9.
Ecosystems produce goods and services that are essential for the wellbeing of humans and other organisms. The earth’s expanding human population is altering both pattern and process in ecosystems, and hence is impacting the provision of ecosystem goods and services at a variety of scales. Food production and other ecosystem services, such as the many benefits provided by forests, are not exclusive of one another at a regional scale. Although it is becoming obvious that uncoordinated local management is inadequate to address regional ecosystem changes in the face of regional drivers of change, few regional governments have addressed the need for holistic landscape management of regional ecosystem services. We compare and contrast two regional programs, the agricultural agenda of integrated pest management (IPM) and an as-yet hypothetical, fragmentation-oriented conservation agenda that we term ‘Regional Fragmentation Management’ (RFM). IPM has a strong practical foundation but is weak on theory. RFM has a stronger theoretical base, but is weak on practice and has mainly focused on protected areas. Both programs address only a small subset of the larger question of how to effectively maintain regional production of regional ecosystem services. Some of the successes of IPM practitioners in building institutions and achieving societal acceptance for their program, particularly in relation to regionally coordinated (‘areawide’) pest management, suggest that regional ecosystem management is plausible. IPM offers some ingredients of an institutional role model for a broader, more ambitious program that seeks to manage regional ecosystem services and processes in a sustainable manner. As the looming crisis of global climate change brings a potential window of opportunity for the introduction of novel approaches for managing deforestation, closer synergies between conservation and agriculture at regional scales seem not only possible, but essential.  相似文献   

10.
The recent development of multistate site occupancy models offers great opportunities to frame and solve decision problems for conservation that can be viewed in terms of site occupancy. These models have several characteristics (e.g., they account for detectability) that make them particularly well suited for addressing management and conservation problems. We applied multistate site occupancy models to evaluate hypotheses related to the conservation and management of Golden Eagles (Aquila chrysaetos) in Denali National Park, Alaska, and provided estimates of transition probabilities among three occupancy states for nesting areas (occupied with successful reproduction, occupied with unsuccessful reproduction, and unoccupied). Our estimation models included the effect of potential recreational activities (hikers) and environmental covariates such as a snowshoe hare (Lepus americanus) index on transition probabilities among the three occupancy states. Based on the most parsimonious model, support for the hypothesis of an effect of potential human disturbance on site occupancy dynamics was equivocal. There was some evidence that potential human disturbance negatively affected local colonization of territories, but there was no evidence of an effect on reproductive performance parameters. In addition, models that assume a positive relationship between the hare index and successful reproduction were well supported by the data. The statistical approach that we used is particularly useful to parameterize management models that can then be used to make optimal decisions related to the management of Golden Eagles in Denali. Although in our case we were particularly interested in managing recreational activities, we believe that such models should be useful to for a broad class of management and conservation problems.  相似文献   

11.
Plant conservation: old problems, new perspectives   总被引:1,自引:0,他引:1  
Nature conservation has changed from an idealistic philosophy to a serious technology(J. Harper, 1992)A review is given of the major conceptual changes that have taken place during the last 50 years in our understanding of the nature of plant conservation and of the principal methodological advances in undertaking conservation assessments and actions, largely through the incorporation of tools and techniques from other disciplines. The interrelationships between conservation and sustainable use are considered as well as the impact of the development of the discipline of conservation biology, the effects of the general acceptance of the concept of biodiversity and the practical implications of the implementation of the Convention on Biological diversity. The effect on conservation policy and management of the accelerating loss or conversion of habitats throughout the world and approaches for combating this are discussed.  相似文献   

12.
Deosai Plateau in Northern Pakistan was designated a national park to protect the largest remnant population of brown bears in Pakistan. The natural resources of this high elevation (3500-5000 m) park make a significant contribution to the livelihood of local and nomad communities. The present legislation excludes people from a park, which increases conflicts between management and local people. However, a pragmatic approach was adopted to involve people in conservation in Deosai. Community participation, achieved by recognizing rights and introducing incentives, reduced resistance against the conservation efforts, reduced grazing pressure in bear habitat and helped reduce poaching. The size of the brown bear population was set as an indicator of park success, and was monitored annually from 1993 through 2006. We observed a 5% annual growth of the brown bear population, suggesting that the conservation program has been successful due to a successful cooperation between an NGO, people, and the park management.The increase of the bear population is significant, because we observed an extremely low reproductive rate, due to late age of first reproduction (8.25 years), a long reproductive interval (5.7 years), and a small litter size (1.33). The reproductive rate of the Deosai population is the lowest yet documented for brown bear populations. Poor habitat quality, low quality food, high seasonality, and extreme weather conditions in the Himalaya probably explain the poor reproductive performance. Considering such low reproduction and known exchange of individuals with neighboring populations, we believe that the observed growth was a sum of reproduction and immigration. Brown bears are declining throughout South Asia and often have low-productive rates. Therefore, conservation efforts for brown bears in this region must target reducing human-caused mortalities, particularly of adult females. Involvement of people can increase efficiency in conservation, in addition to reducing cost and conflicts.  相似文献   

13.
Tree reactions and dune movements: Slowinski National Park,Poland   总被引:2,自引:0,他引:2  
The effects on tree growth of both climatic and non-climatic variables were investigated in relation to dune dynamics at three sites on the Czolpinska dune in the Slowinski National Park, Poland where aeolian sediments are invading a forest of Scots Pine (Pinus sylvestris L.). We found that where dune advance was relatively rapid, tree vitality declined after stem burial was over 1.9 m, but where advance was under 1 m/yr survival was remarkably increased, one tree survived, albeit with thinning needles, after an estimated 11.4 m burial. Below sand-surface stem discs, cut 0.5 m apart, from a heavily suppressed tree revealed a difference in narrow-ring reactions of up to 2 years over a 2 m burial distance; the discs also showed a time lag of 4 years before compression wood formation. Consequently, when estimating sand-movement rates we discounted compression wood reactions; we also excluded climatic events and pest infestations. The remaining data supplied a sand-advance rate at Site 1 from 2.4 to 3.5 m/yr. At Site 2, rates were from 1.2 to 2.5 m/yr, with a direct measurement of 0.3 m/yr between 2006 and 2007. At Site 3 rates were from 0.3 to 1.2 m/yr, with dune migration here virtually at a standstill over the last seven years. Direct measurement of sand movement (3.03 m/yr) at Site 1 was slower than the lowest rate (3.5 m/yr) previously recorded by Borówka (1980) for the larger dune system.  相似文献   

14.
Wolves are important components in the northern and western Canadian National Parks. Within Jasper National Park their numbers have undergone wide fluctuations. One cause of these fluctuations can be traced to the predator control programmes in areas adjacent to the National Parks. An examination of the historical records indicates that Wolves were widely persecuted also within the Parks in the past. Such activities have now largely ceased; however, increased human visitation has placed new pressures on these large carnivores. There is a need for public education to gain an acceptance of Wolf predation on ungulates in the Parks, although ungulates are traditionally one of the favoured attractions to North American National Parks.  相似文献   

15.
The problem of ‘excess Elephants’ in Tsavo National Park, Kenya, came to a head with the die-off during the 1970–1971 drought. Like many parts of Africa, Tsavo is being threatened in its workings—and, in the long run, in its existence—by the pressure of people in the environs. Tsavo's present travails epitomize many of the threats facing Africa's wildlife refuges. These problems of conservation require solutions that are much more complex than they would have been in the past—solutions which will reflect the balances of the entire environment, outside the park as well as inside. A wildlife ecosystem demonstrates characteristics which can scarcely be predicted from the properties of its constituent components. It embodies a different and higher level of organization (an ‘emergent quality’) which cannot be perceived by looking with microscopic intensity at any particular part, but only with a microscopic perspective at the total pattern. By extension, Tsavo can be taken as a measure of how far people around the world are ready to assist in safeguarding Africa's wildlife, and what costs they are willing to bear—in terms of their pockets and philosophies alike. This survey of the present position at Tsavo attempts to propose perspectives which do not always receive as much attention as they should.  相似文献   

16.
This study tests the potential utility of Stakeholder Analysis to Protected Area management. Using Corbett National Park (CNP), India, as a case study, Stakeholder Analysis (SA) was used to identify important stakeholder groups and assess their relationships, relative power and importance. This exercise was undertaken to assist the managers of CNP with future strategy formulation and implementation. The results demonstrate SA to be a simple, yet effective, method that can help PA managers understand the social dimensions of their undertaking, without waiting for long-term policy changes. The results reveal possible stakeholder alliances, and those that may need strengthening to guarantee the welfare of CNP. Divergent opinions on the same issue were also discovered. This underlines that addressing low levels of knowledge and misplaced information may be of strategic importance in reducing conflict against a PA. This research also helps theorize previously unexplored relationships among stakeholders in India, using the framework of Stakeholder Theory. Repeating the exercise on a regular basis could help PA managers monitor stakeholder interactions and political positions over time.  相似文献   

17.
Human-killing is the ultimate expression of human-tiger conflict. It is a complex issue that needs to be addressed to maintain support for tiger (Panthera tigris) conservation in areas where human-killing is prevalent. This research was undertaken to investigate the ecological and sociological aspects of human-killing in the central lowlands of Nepal. We used 28 years of data from human-killing events in Chitwan National Park and the surrounding area to: (1) document the geographic distribution of human-killing incidents, (2) examine ecological variables associated with sites where humans were killed, (3) characterize human-killing tigers, and (4) identify human activities that make people vulnerable to attack. Finally, we use this information to recommend strategies to reduce human-tiger conflicts. Data on human-killing incidents and removal of human-killing tigers were obtained from veterinarian and Kathmandu Zoo records and by visiting the location of each kill with a victim’s family member or friend. Thirty-six tigers killed 88 people from 1979 to 2006. Most (66%) kills were made within 1 km of forest edge but equally in degraded and intact forests. An equal number of male and female tigers killed humans and 56% of tigers that were examined had physical deformities. The trend of human deaths increased significantly from an average of 1.2 (±1.2) persons per year prior to 1998 to 7.2 (±6.9) per year from 1998 to 2006. This difference is due primarily to a ten fold increase in killing in the buffer zone since 1998 because of forest restoration. Nearly half the people killed were grass/fodder collectors. Local participation in tiger management and conservation is essential to mitigate human-tiger conflicts. We recommend that villagers be recruited to help radio collar and monitor potentially dangerous tigers, participate in long term tiger monitoring, and attend a tiger conservation awareness program focused on tiger behavior and avoidance of conflict.  相似文献   

18.
The invasive Argentine ant Linepithema humile was found in close perimeters to inhabited houses situated in various habitat types in Doñana National Park (Southern Spain). We suggest that the Argentine ant is found in these sites largely due to passive importation by man, but from there may have the potential to spread into surrounding favourable natural habitats. Ant species richness and diversity around houses was similar to that in natural habitats, except in the cases where the Argentine ant dominated, where a considerable lower ant species diversity and richness was observed. The species composition of ants in the immediate vicinity of houses was very different from that of the surrounding natural habitats, although the species composition between houses was very similar, regardless of the type of surrounding natural habitat. Ant species around houses were typically generalists, opportunists or open habitat specialists. Many of these species are considered dominant in that they are characterised by having large nests, aggressive behaviour and mass recruitment in response to attack. However, these species are displaced by the Argentine ant when introduced. Not all ant species show the same responses to invasions by the Argentine ant, and some species, such as Cardiocondyla batesii, Oxyopomyrmex saulcyi or Cataglyphis floricola, may be able to persist for a period following an invasion of the Argentine ant. These species are characterised by small nests and submissive behaviour, and may survive by avoiding conflict with the invasive species.  相似文献   

19.
The conservation of remnant populations of white-lipped peccaries in Central America depends on adequate documentation of their habitat needs and behavior. Thus, we monitored the activity patterns, local distributions, and home ranges of 36 (25F:11M) radio-marked white-lipped peccaries, all members of a single “super” herd, in part of Corcovado National Park, their largest stronghold in Costa Rica, during 1996-1998. Peccaries were diurnal all year with a period of reduced activity during the middle of the day. They were found more often than expected (vs. random use) in primary forest during February to May, in secondary and coastal forest during June to September, and in herbaceous swamp during October to January, corresponding to relative fruit abundance. Overall, the peccary herd ranged over an area of <40 km2, but use of the area shifted seasonally and movements were reduced when fruit was most abundant. Our data agree with the suggestion that peccary density may be higher where the interspersion or close proximity and mix of seasonally important habitats is high, and thus where peccaries do not have to travel as far for food. Habitat interspersion is therefore a significant conservation concern and should be addressed to make certain that peccary populations are not limited.  相似文献   

20.
Using a historical reconstruction, we discovered a potential trophic cascade involving cougar (Puma concolor), mule deer (Odocoileus hemionus), and California black oak (Quercus kelloggii) in the Yosemite Valley of Yosemite National Park in California. Our objective was to determine whether large deer populations in the absence of a top-level carnivore were suppressing tree regeneration. As human visitation increased in the early 1900s and cougar became increasingly scarce, the mule deer population irrupted in the 1920s. In August 2006, we undertook a retrospective study of black oak recruitment (i.e., growth of seedling/sprouts into tall saplings and trees) by inventorying all black oaks in stands accessible to deer and greater than 0.5 ha in size (18 stands, 2921 trees). We similarly inventoried oaks within sites representing refugia from deer browsing (4 stands, 481 trees). While significantly diminished oak recruitment has occurred since the 1920s in stands accessible to deer (p < 0.01), continuous recruitment of oaks was found in refugia sites. We also found less oak recruitment in areas of high human activity near the park’s visitor center (p < 0.01), possibly due to behaviorally-mediated effects of lower cougar and higher deer densities. Overall our results are consistent with trophic cascade theory involving large predators, herbivores, and plants. The long-term lack of oak recruitment is also an indicator of a probable loss of biodiversity.  相似文献   

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