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Successful conservation plans are not solely achieved by acquiring optimally designed reserves. Ongoing monitoring and management of the biodiversity in those reserves is an equally important, but often neglected or poorly executed, part of the conservation process. In this paper we address one of the first and most important steps in designing a monitoring program – deciding what to monitor. We present a strategy for prioritizing species for monitoring and management in multispecies conservation plans. We use existing assessments of threatened status, and the degree and spatial and temporal extent of known threats to link the prioritization of species to the overarching goals and objectives of the conservation plan. We consider both broad and localized spatial scales to capture the regional conservation context and the practicalities of local management and monitoring constraints. Spatial scales that are commensurate with available data are selected. We demonstrate the utility of this strategy through application to a set of 85 plants and animals in an established multispecies conservation plan in San Diego County, California, USA. We use the prioritization to identify the most prominent risk factors and the habitats associated with the most threats to species. The protocol highlighted priorities that had not previously been identified and were not necessarily intuitive without systematic application of the criteria; many high‐priority species have received no monitoring attention to date, and lower‐priority species have. We recommend that in the absence of clear focal species, monitoring threats in highly impacted habitats may be a way to circumvent the need to monitor all the targeted species.  相似文献   

3.
Conservation strategies are often established without consideration of the impact of climate change. However, this impact is expected to threaten species and ecosystem persistence and to have dramatic effects towards the end of the 21st century. Landscape suitability for species under climate change is determined by several interacting factors including dispersal and human land use. Designing effective conservation strategies at regional scales to improve landscape suitability requires measuring the vulnerabilities of specific regions to climate change and determining their conservation capacities. Although methods for defining vulnerability categories are available, methods for doing this in a systematic, cost‐effective way have not been identified. Here, we use an ecosystem model to define the potential resilience of the Finnish forest landscape by relating its current conservation capacity to its vulnerability to climate change. In applying this framework, we take into account the responses to climate change of a broad range of red‐listed species with different niche requirements. This framework allowed us to identify four categories in which representation in the landscape varies among three IPCC emission scenarios (B1, low; A1B, intermediate; A2, high emissions): (i) susceptible (B1 = 24.7%, A1B = 26.4%, A2 = 26.2%), the most intact forest landscapes vulnerable to climate change, requiring management for heterogeneity and resilience; (ii) resilient (B1 = 2.2%, A1B = 0.5%, A2 = 0.6%), intact areas with low vulnerability that represent potential climate refugia and require conservation capacity maintenance; (iii) resistant (B1 = 6.7%, A1B = 0.8%, A2 = 1.1%), landscapes with low current conservation capacity and low vulnerability that are suitable for restoration projects; (iv) sensitive (B1 = 66.4%, A1B = 72.3%, A2 = 72.0%), low conservation capacity landscapes that are vulnerable and for which alternative conservation measures are required depending on the intensity of climate change. Our results indicate that the Finnish landscape is likely to be dominated by a very high proportion of sensitive and susceptible forest patches, thereby increasing uncertainty for landscape managers in the choice of conservation strategies.  相似文献   

4.
Since 1999, SPVS has been involved in three projects that combine two fundamental goals over the course of 40 years: the conservation of one of Brazil's most important remnants of Atlantic Forest and the implementation of projects for carbon sequestration. In addition, there is an interest in replicating these projects in order to restore other degraded areas, protect the Brazilian biomes, and help to diminish deforestation and forest fire, therefore reducing carbon emissions. The acquisition of 19,000 ha of degraded areas of high biological importance in southern Brazil was the first step towards the implementation of the projects. These areas are owned by SPVS, a Brazilian NGO, and are being restored, conserved and transformed into Private Natural Reserves, in partnership with the NGO – The Nature Conservancy, and financed by the companies – American Electric Power, General Motors and Chevron Texaco. The process of forest restoration involves several stages: soil studies, surveying the region's native plants, planning for restoration by means of a Geographical Information System, production of seedlings, application of different techniques for planting (such as manual or mechanised planting with seedlings and stakes), and biomass and biodiversity monitoring. To guarantee the survival of the seedlings on the planted areas, during the first three years, there is a continuous and systematic maintenance programme including weeding of undergrowth, crowing and organic fertilisation. The three projects already planted around 500,000 seedlings of native species until September 2004, and aim to plant a further 300,000 until 2008.  相似文献   

5.
The spatial-temporal variation of understory light availability has important influences on species diversity and community assembly. However, the distribution characteristics and influencing factors of understory light availability have not been fully elucidated, especially in temperate deciduous, broad-leaved forests. In this study, the understory light availability was monitored monthly (May–October) in a temperate deciduous, broad-leaved forest in Henan Province, China. Differences in the light availability among different months and habitat types were statistically analyzed using Kruskal–Wallis method, respectively. Partial least squares path modeling (PLS-PM) was used to explore the direct and/or indirect effects of stand structure, dominant species and topographic factors on the light environment. Results showed that there were differences in light environments among the four habitat types and during the studied six months. The PLS-PM results showed that the stand structure and the dominant species were negatively correlated with the light environment, and the path coefficient values were −0.089 (P = 0.042) and −0.130 (P = 0.004), respectively. Our result indicated that the understory light availability exhibit a distinct spatial and temporal heterogeneity in temperate deciduous, broad-leaved forest of north China. The characteristics of woody plant community, especially the abundance of one of the dominant plant species, were the important factors affecting the understory light availability.  相似文献   

6.

Background

Cameroon is known as Africa in miniature because of its multitude of ecosystems and associated biodiversity, cultures and traditions. The country also harbors very ancient human populations whose relationship with nature is very intimate and where animals play important roles for their livelihood. Located in the South-west region of Cameroon, the Nkwende Hills Forest Reserve (NHFR) represents an important wildlife conservation site because of its strategic position at the periphery of Korup National Park (KNP). The periphery of NHFR is inhabited by several ethnic groups amongst which are the Obang and Ngunnchang clans who share particular relationships with wildlife. The present paper studies these relationships and contributes to the growing trend of scientific ethnozoological studies across Africa.

Method

From August to December 2011, a questionnaire survey was addressed to 126 randomly chosen household respondents (HRs) in seven villages at the Northwest periphery of NHFR. In households, preference was given to parents, and to the eldest child in case the parents were absent. Questions related to the uses and local taboos on wildlife species were asked to HRs.

Results

Both communities have accumulated knowledge on the use of 51 wildlife species of which 50.9% represent mammals, 21.6% birds, 15.7% reptiles, 7.8% fish and 3.9% invertebrates. Four main use categories of wildlife by both communities were identified, namely (1) Food, medicine and sales values (41.2%), (2) Ethnomusical animals and parts used as trophy (29.2%), (3) Decoration and jewelry making values (21.9%) and (4) Magico-religious and multipurpose values (7.8%). Regarding local taboos, species specific taboos (generation totems and acquired totems), habitat taboos (sacred forests), method and segment taboos still persist but are rarely respected among the youth mainly because of the scarcity of wildlife (65.3% of HRs).

Conclusion

Like other communities living around forest areas, the studied communities use wildlife in their culture and tradition. Wildlife is not only used for consumption, but also for traditional medicines, craft materials and spiritual purposes. But, threats to wildlife and their traditional uses are real and acculturation seems to be the main driver. High priority should be given to the reconciling conservation of species with high values for local communities and human needs.  相似文献   

7.
Although the aim of conservation planning is the persistence of biodiversity, current methods trade-off ecological realism at a species level in favour of including multiple species and landscape features. For conservation planning to be relevant, the impact of landscape configuration on population processes and the viability of species needs to be considered. We present a novel method for selecting reserve systems that maximize persistence across multiple species, subject to a conservation budget. We use a spatially explicit metapopulation model to estimate extinction risk, a function of the ecology of the species and the amount, quality and configuration of habitat. We compare our new method with more traditional, area-based reserve selection methods, using a ten-species case study, and find that the expected loss of species is reduced 20-fold. Unlike previous methods, we avoid designating arbitrary weightings between reserve size and configuration; rather, our method is based on population processes and is grounded in ecological theory.  相似文献   

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Many natural processes in the riparian cottonwood (Populus deltoides) forest of the Middle Rio Grande (MRG) in the southwestern United States have been disrupted or altered, allowing non‐native plants such as saltcedar (Tamarix spp.) and Russian olive (Elaeagnus angustifolia) to establish. We investigated reptilian responses to restoration efforts by sampling communities of lizards at 12 study sites invaded by non‐native plants along the MRG in New Mexico for 7 years (2000–2006). Sites within three regions were randomly assigned to one of the three treatments to remove non‐native plants and woody debris, or as untreated controls. We used pitfall and funnel traps to capture, mark, and release lizards from June to September. Principal components analysis of 15 vegetation variables identified five factors that best explained variation among sites before and after removal of non‐native plants. Relative abundances for four of six common species of lizards were associated with vegetation characteristics that significantly changed after plant removal. Species were either positively associated with the more open, park‐like understory found in treated sites or negatively associated with debris heaps and thickets of non‐native plants found in untreated sites. Eastern fence lizards (Sceloporus consobrinus) and New Mexico whiptails (Aspidoscelis neomexicana) increased in relative abundance after non‐native plants were removed. Overall, removal of non‐native plants seems beneficial, or at least is non‐damaging, to lizard communities of the MRG forest. Providing information on habitat associations of lizard communities will help land managers balance management objectives with other considerations, such as providing important wildlife habitat.  相似文献   

11.
Using mechanical treatments to mimic natural disturbances is becoming a standard management and restoration approach. In the Sierra Nevada, as throughout much of western North America, much of aspen habitat is in poor health. Because of the high ecological value of healthy aspen, and its limited extent on the landscape, restoration to reverse the decline and improve stand health has become a management priority in the region. To evaluate the ecological effects of mechanically removing competing conifers to restore aspen in the Sierra Nevada, we compared vegetation characteristics and bird abundance in treated and untreated aspen stands on the Lassen National Forest before and up to 13 years after mechanical conifer removal. Treatments reduced total canopy cover and increased herbaceous cover and the number of aspen stems, while shrub and overstory aspen covers were unchanged. Of 10 aspen focal bird species, 7 increased in abundance following treatment relative to controls, including all species associated with early seral aspen habitat and cavity nesting species; none declined. In contrast, of the six conifer focal species, the four associated with denser conifer habitat declined as a result of the treatments. The two species associated with conifer edges and understory cover increased. Our results demonstrate mechanical conifer removal treatments can provide ecologically meaningful changes in habitat for the avian community and are an effective tool for restoring ecological values of degraded aspen habitat for birds in the Sierra Nevada.  相似文献   

12.
Abstract

The impact of climate change on conservation planning is affected by the availability of data (especially in data-sparse countries) and socioeconomic impacts. We build models using MaxEnt for Egyptian medicinal plants as a model system, projecting them to different future times under two IPCC 4th assessment emission scenarios (A2a and B2a) assuming unlimited and no dispersal. We compare the effect of two indices of socioeconomic activity [Human Influence Index (HII) and human population density/km2] as cost layers in spatial prioritization for conservation using zonation. We assess the efficacy of Egypt's network of Protected Areas (PAs) by comparing the predicted conservation value inside and outside each PA under the various scenarios. The results show that there are many locations in Egypt (the main cities, agricultural land, coastal areas) that are highly ranked for conservation before human socioeconomic impacts are included. The HII had a stronger impact than using human population density. The PA value excess (inside–outside) varied significantly with the type of cost and dispersal, but not with climate-change scenario or Zonation settings. We conclude that human socioeconomic impacts add new scope and insights for future conservation; and conservation planning without consideration of such impacts cannot be complete.  相似文献   

13.
Phenological events, such as bud burst, are strongly linked to ecosystem processes in temperate deciduous forests. However, the exact nature and magnitude of how seasonal and interannual variation in air temperatures influence phenology is poorly understood, and model‐based phenology representations fail to capture local‐ to regional‐scale variability arising from differences in species composition. In this paper, we use a combination of surface meteorological data, species composition maps, remote sensing, and ground‐based observations to estimate models that better represent how community‐level species composition affects the phenological response of deciduous broadleaf forests to climate forcing at spatial scales that are typically used in ecosystem models. Using time series of canopy greenness from repeat digital photography, citizen science data from the USA National Phenology Network, and satellite remote sensing‐based observations of phenology, we estimated and tested models that predict the timing of spring leaf emergence across five different deciduous broadleaf forest types in the eastern United States. Specifically, we evaluated two different approaches: (i) using species‐specific models in combination with species composition information to ‘upscale’ model predictions and (ii) using repeat digital photography of forest canopies that observe and integrate the phenological behavior of multiple representative species at each camera site to calibrate a single model for all deciduous broadleaf forests. Our results demonstrate variability in cumulative forcing requirements and photoperiod cues across species and forest types, and show how community composition influences phenological dynamics over large areas. At the same time, the response of different species to spatial and interannual variation in weather is, under the current climate regime, sufficiently similar that the generic deciduous forest model based on repeat digital photography performed comparably to the upscaled species‐specific models. More generally, results from this analysis demonstrate how in situ observation networks and remote sensing data can be used to synergistically calibrate and assess regional parameterizations of phenology in models.  相似文献   

14.
Freshwater ecosystems provide vital resources for humans and support high levels of biodiversity, yet are severely threatened throughout the world. The expansion of human land uses, such as urban and crop cover, typically degrades water quality and reduces freshwater biodiversity, thereby jeopardizing both biodiversity and ecosystem services. Identifying and mitigating future threats to freshwater ecosystems requires forecasting where land use changes are most likely. Our goal was to evaluate the potential consequences of future land use on freshwater ecosystems in the coterminous United States by comparing alternative scenarios of land use change (2001–2051) with current patterns of freshwater biodiversity and water quality risk. Using an econometric model, each of our land use scenarios projected greater changes in watersheds of the eastern half of the country, where freshwater ecosystems already experience higher stress from human activities. Future urban expansion emerged as a major threat in regions with high freshwater biodiversity (e.g., the Southeast) or severe water quality problems (e.g., the Midwest). Our scenarios reflecting environmentally oriented policies had some positive effects. Subsidizing afforestation for carbon sequestration reduced crop cover and increased natural vegetation in areas that are currently stressed by low water quality, while discouraging urban sprawl diminished urban expansion in areas of high biodiversity. On the other hand, we found that increases in crop commodity prices could lead to increased agricultural threats in areas of high freshwater biodiversity. Our analyses illustrate the potential for policy changes and market factors to influence future land use trends in certain regions of the country, with important consequences for freshwater ecosystems. Successful conservation of aquatic biodiversity and ecosystem services in the United States into the future will require attending to the potential threats and opportunities arising from policies and market changes affecting land use.  相似文献   

15.
中国天然林保护工程区森林覆盖遥感监测   总被引:2,自引:2,他引:2  
天然林资源保护工程(天保工程)自1998年开始实施至2020年底结束,标志着我国林业由以木材生产为主向以生态建设为主进行转变,对天然林资源开展定量监测与评估,有助于全面、及时、科学地评价天保工程对森林资源的保护成效。基于公开发布的土地覆盖产品,利用新的遥感数据合成算法构建了森林类型综合提升方法,生产了一套我国天保工程区的森林覆盖产品,对天保工程区1997年至2020年间的森林覆盖情况开展监测与评估。利用中国森林生态系统定位研究网络数据(CFERN)、森林资源规划设计调查数据和地面调查数据进行精度检验,森林类型的分类精度优于90%。分析结果显示,自天保工程实施以来,工程区的森林覆盖度总体呈恢复性增长趋势,森林覆盖从1997年的30.15%增长到2020年的31.74%,净增长1.59%,其中,长江上游地区森林增长量最高,占全工程区森林增长面积的50.97%。研究结果表明我国天保工程区内森林资源得到有效保护和恢复,天保工程实施效果显著。  相似文献   

16.
In 2009, a group of practitioners took action to restore 175 miles of riparian habitat impaired by invasive plants along the Dolores River in southwestern Colorado and eastern Utah. Recognizing the magnitude of ecological, jurisdictional, and management challenges associated with this large‐scale initiative, this group of managers built trust and relationships with key partners to foster collaboration across boundaries and cultivate consensus of a variety of perspectives and forms of knowledge. What emerged was a network of individuals, organizations, and agencies dedicated to restoring the Dolores River riparian corridor while sharing information and learning from one another. This public–private collaboration, called the Dolores River Restoration Partnership (DRRP), has been successful in creating a process by which financial, technical, and human resources are shared across boundaries to restore a riparian corridor. Specifically, the DRRP developed effective planning documents, a responsive governance structure, monitoring protocols, and a shared mindset for extracting lessons learned that have been instrumental in making progress toward its shared restoration goals and addressing a wide variety of restoration challenges. The tools developed by the partnership and lessons learned from their utility are outlined in this case study as a means to inform other collaborative restoration efforts.  相似文献   

17.
Dispersal by frugivorous birds facilitates invasion by many exotic plants. We measured the seed rain of ornithochorous native and exotic plants at three habitats of a fragmented landscape of the northeastern United States for 1 year. We studied maple-beech forests, old fields, and abandoned conifer plantations. Across all sites we collected 2,196 ornithochorous seeds, including seeds from six exotic species and 10 native species. The majority (90%) of collected seeds were from exotic species. Seed dispersal was broadly similar among habitats, though seed rain of exotic species was higher in old fields than forested habitats. Seed rain was not strongly influenced by artificial perches for most species. However, seeds of exotic species were more commonly found in traps under an artificial perch in old fields. Seed rains for the exotic Elaeagnus umbellata, Rhamnus cathartica, and Rosa multiflora were positively associated with local density of mature plants. Seed rain of R. cathartica was positively associated with abundance of seedlings but not saplings, suggesting that post-dispersal mortality was important. Seed dispersal of the exotic Lonicera spp. was high in all habitats, accounting for 66% of all seeds collected. With the exception of Lonicera spp., seed rain of common exotic invaders was affected by the abundance of seed sources, and these species might be effectively controlled by elimination of local fruiting plants. Fruits of Lonicera morrowii, which has extensively invaded our area, are apparently a common component in the diet of frugivores.  相似文献   

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19.
Species conservation requires an understanding of the factors and interactions affecting species distribution and behavior, habitat availability and use, and corresponding vital rates at multiple temporal and spatial scales. Opportunities to investigate these relationships across broad geographic regions are rare. We combined long-term waterfowl population surveys, and studies of habitat use and breeding success, to develop models that identify and incorporate these interactions for upland-nesting waterfowl in the Prairie Pothole Region (PPR) of Canada. Specifically, we used data from the annual Waterfowl Breeding Population and Habitat Survey (1961–2009) at the survey segment level and associated habitat covariates to model and map the long-term average duck density across the Canadian PPR. We analyzed nest location and fate data from approximately 25,000 duck nests found during 3 multi-year nesting studies (1994–2011) to model factors associated with nest survival and habitat selection through the nesting season for the 5 most common upland nesting duck species: mallard (Anas platyrhynchos), gadwall (Mareca strepera), blue-winged teal (Spatula discors), northern shoveler (Spatula clypeata), and northern pintail (Anas acuta). Duck density was highly variable across the Canadian PPR, reflecting positive responses to local wetland area and count, and amounts of cropland and grassland, a regional positive response to latitude, and a negative response to local amounts of tree cover. Nest survival was affected by temporal and spatial variables at multiple scales. Specifically, nest survival demonstrated interactive effects among species, nest initiation date, and nesting cover type and was influenced by relative annual wetness, population density, and surrounding landscape composition at landscape scales, and broad geographic gradients (east-west and north-south). Likewise, species-specific probability of nest habitat selection was influenced by timing of nest initiation, population density, relative annual wetness, herbaceous cover, and tree cover in the surrounding landscape, and location within the Canadian PPR. We combined these models, with estimates of breeding effort (nesting, renesting, and nest attempts) from existing literature, in a stochastic conservation planning model that estimates nest distribution and success given spatiotemporal variation in duck density, habitat availability, and influential covariates. We demonstrate the use of this model by examining various conservation planning scenarios. These models allow estimation of local, landscape, and regional influence of conservation investments and other landscape changes on the productivity of breeding duck populations across the PPR of Canada. These models lay the groundwork for the incorporation of conservation delivery costs for full return-on-investment analyses and scenario analyses of climate, habitat, and land use change in regional and continental population models.  相似文献   

20.
Miscanthus sinensis (Anderss.) is a perennial grass species that has been grown widely as an ornamental since the late 1800s and is now being considered for bioenergy production in the United States. With its ability to be grown from seed and tolerate cold climates, this species offers practical advantages over current cultivars of the higher‐yielding hybrid species, M.×giganteus. Yet a large‐scale release of M. sinensis for bioenergy production in colder northern regions could result in new invasions into natural areas. We show, with reference to historical records and data collected in six wild US populations of M. sinensis in 2009, that ornamental varieties of this species have a long history of localized escape in the Eastern United States, primarily within the Appalachian region. To prevent further escape and gene flow, we recommend the development of sterile or functionally sterile varieties of M. sinensis or the restriction of its usage as a donor of genetic material to new sterile cultivars of M. ×giganteus. Other appropriate precautions for new biomass varieties include experimental demonstration of low invasiveness in the target region ahead of commercial production, along with postintroduction stewardship programs.  相似文献   

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