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1.
Global climate and land-use changes are the most significant causes of the current habitat loss and biodiversity crisis. Although there is information measuring these global changes, we lack a full understanding of how they impact community assemblies and species interactions across ecosystems. Herein, we assessed the potential distribution of eight key woody plant species associated with the habitat of the endangered Lilac-crowned Amazon (Amazon finschi) under global changes scenarios (2050′s and 2070′s), to answer the following questions: (1) how do predicted climate and land-use changes impact these species’ individual distributions and co-distribution patterns?; and (2) how effective is the existing Protected Area network for safeguarding the parrot species, the plant species, and their biological interactions? Our projections were consistent identifying the species that are most vulnerable to climate change. The distribution ranges of most of the species tended to decrease under future climates. These effects were strongly exacerbated when incorporating land-use changes into models. Even within existing protected areas, >50 % of the species’ remaining distribution and sites with the highest plant richness were predicted to be lost in the future under these combined scenarios. Currently, both individual species ranges and sites of highest richness of plants, shelter a high proportion (ca. 40 %) of the Lilac-crowned Amazon distribution. However, this spatial congruence could be reduced in the future, potentially disrupting the ecological associations among these taxa. We provide novel evidence for decision-makers to enhance conservation efforts to attain the long-term protection of this endangered Mexican endemic parrot and its habitat. 相似文献
2.
Suzanne M. Hodgkinson Mary Schmidt Nelson Ulloa 《Animal Feed Science and Technology》2008,144(1-2):167-173
The objective of the current study was to compare the digestible energy (DE) contents of maize, oats and alfalfa meal between European wild boar (Sus scrofa L.) and the domestic pig (S. scrofa domesticus, Landrace × Large White). Six pure wild boar (S. scrofa L.) and six domestic pigs (Landrace × Large White) with liveweights (mean ± S.E.M.) of 26 ± 0.6 and 21 ± 1.1 kg, respectively, were fed diets at a daily level of 0.10 × metabolic body weight (W0.75). The diets included a base diet and three experimental diets containing 700 g basal diet/kg and 300 g maize, oats or alfalfa meal/kg; all animals received all four diets. Chromic oxide was used as indigestible marker. The animals received each diet for an 8-day period with fecal samples collected on days 6, 7 and 8. The DE content of the maize, oats and alfalfa was calculated for each ingredient and statistically compared between the wild boar and domestic pig. For the maize and oats, there was no significant difference in the DE values between the domestic pig and wild boar. However, the DE value of the alfalfa was greater in the domestic pig (10.56 MJ kg−1 DM) than in the wild boar (8.48 MJ kg−1 DM). For ingredients that contain relatively low concentrations of fibre (such as maize and oats), it appears that DE values determined in the domestic pig can be validly applied for diet formulation for wild boars; however, for ingredients with higher fibre levels, the DE values in wild boar appear to be lower than those in the domestic pig. 相似文献
3.
Mollusca is a megadiverse phylum with an estimated number of 70,000–76,000 described species which can inhabit a wide variety of environments. Among them, land snails are a main component of terrestrial ecosystems and they play a pivotal role in ecosystem functioning. They are suffering habitat loss, overexploitation and competition from introduced species, but are regarded as a “non-charismatic” group for conservation purposes. Orthalicoidea is a dominant faunal element in the Neotropics and in Argentina includes 104 species that inhabit a variety of environments. Their abundance, diversity, comprehensive taxonomy and widespread representation in different ecoregions makes this molluscan group an excellent model for biodiversity assessments. The database used here consisted of 985 unique geographic records of 104 species. Species distribution models were generated using the Maximum Entropy method and Zonation v 3.1 was used to evaluate the proposed conservation goals. Three analyses including species distributions, the current protected areas system (PAs) and the Human print layer were carried out. This allowed the identification of priority areas for conservation, the percentage of the species distribution under PAs and analysis of the potential impacts under current land use and in the priority areas detected above. Sixty-one species were modeled, and 59 of them were included in the priority area selection process due to their high area under curve (AUC) scores. Five high priority areas located in the different ecoregions, were identified: 1-dry Chaco, 2-humid Pampas, 3-Southern Andean Yungas, 4-Alto Paraná Atlantic Forests and 5-high Monte. A small percentage of the average distribution range of Orthalicoidean species (3%) was within the current protected areas. Highest-ranked priority areas for land snails are outside the current protected areas system. When human impact is considered, the priority areas are reduced in size and appear as small patches. However, highest priority areas for conservation continue being those detected in the above analyses. Most of the areas detected are used for economic purposes, creating conflicts of interest between the development of human activities and conservation. This study represents one of the first attempts to identify ecoregion level priority areas for a terrestrial invertebrate group. Further analyses, including new predictors and other molluscan taxa, would improve planning the conservation of poorly known invertebrate groups. 相似文献
4.
Fir forests (Abies, Pinaceae) are dominant in temperate regions of North America; however, they have experienced high degradation rates that can threaten their long-term continuity. This study aimed to identify the priority areas for the conservation of the genus Abies in North America. First, we modeled the species distribution of the 17 native species through ecological niche modeling, considering 21 environmental variables. Then, we defined the priority areas through multi-criteria analysis, considering the species richness, geographic rareness, irreplaceability, habitat degradation, and risk extinction. We also built six scenarios, giving more priority to each criterion. Finally, we identified the proportion of the extent of the priority areas covered by protected areas. Elevation, precipitation seasonality, and winter precipitation influenced the distribution of most of the Abies species. When considering equal weights to each criterion, the priority areas summed up 6% of the total extent covered by the Abies species in North America. Most priority areas were located on the West Coast of the United States, the Eastern Sierra Madre, Southern Sierra Madre, Sierras of Chiapas and Central America, and the Trans-Mexican Volcanic Belt ecoregions. In these ecoregions, the Abies species are restricted to small areas facing high degradation levels. Only 16% of the area covered by the Abies species in North America is protected, mainly under restrictive schemes such as National Parks and Wilderness Areas. The priority areas identified could be the basis for establishing or enlarging protected areas. The preservation of the genus Abies could also maintain other ecological features and processes such as biodiversity, forest resources, and environmental services. 相似文献
5.
In many developing nations, “paper parks”, or protected areas that have little or no formal management on the ground, have resulted from the failure of protected area systems to achieve their foremost goal: biodiversity conservation. This analysis incorporates biophysical, socioeconomic, and land use/tenure data collected by a multi-disciplinary team of Guatemalan and American researchers in order to identify potential management plans and multiple-use/concession arrangements. The Sierra Chinajá is a classic paper park protected area in Guatemala. Many factors have rendered Guatemalan protected areas management policies ineffectual in the Sierra Chinajá despite the fact that it has been an “area of special protection” since 1989. Proximate causes of forest conversion mask underlying driving forces responsible for rapid biodiversity loss. Despite the fact that Guatemala’s protected areas management system is similar to that promoted by international conservation organizations it has yet to effectively conserve biodiversity. These factors suggest that protected areas management in Guatemala, and other developing nations possessing unique cultural and natural histories, must be rooted in the local context as promulgated by the local non-governmental organization ProPéten in their proposal for an official Indigenous Reserve category. The proposal suggests the devolution of management responsibilities from federal institutions to local communities in the effort to develop a community-based, site specific conservation agenda.
Resumen En muchos países en desarrollo, las “áreas protegidas en papel” o parques que no poseen un plan de manejo formal, han sido el resultado de la incapacidad del sistema nacional de áreas protegidas de alcanzar su meta mas importante: la conservación de la biodiversidad. El siguiente análisis incorpora datos biofísicos, socioeconómicos, de uso y tenencia de la tierra recolectados por un grupo multidisciplinario de investigadores guatemaltecos y norteamericanos con el objetivo de formular una estrategia de conservación que incorpore concesiones de usos múltiples. La Sierra de Chinajá es un ejemplo clásico de un “área protegida en papel” en Guatemala. Muchos son los factores por los cuales la política de áreas protegidas ha fracasado en la Sierra de Chinajá, a pesar de estar clasificada como un “área de Protección Especial” desde 1989. Las causas subyacentes responsables por el cambio en la cobertura forestal están escondidas debajo de los síntomas más visibles de la perdida de biodiversidad. A pesar de que el Sistema Guatemalteco de áreas Protegidas es similar al promovido por organizaciones internacionales aun no es efectivo en la conservación de la biodiversidad. Estos factores sugieren que el manejo de las áreas protegidas en Guatemala, y en otros países en desarrollo que poseen historias naturales y culturales únicas, deben estar enraizadas en el contexto local, como ha sido propuesto por la organización Pro-Peten en su propuesta por una categoría de manejo denominada Reservas Comunitarias Indígenas. La propuesta sugiere la delegación de la protección la biodiversidad de instituciones estatales a las comunidades locales con el propósito de establecer una agenda de conservación basada en el manejo comunitario.相似文献
6.
野猪及其与家猪杂种猪Myostatin基因3'编码区的克隆和序列分析 总被引:8,自引:0,他引:8
Myostatin, which is a highly conservative gene among breeds, is a negative regulator of muscle. The 3' coding region of wild boar and crossbred pig myostatin was cloned by RT - PCR and sequenced. Compared with that of GenBank, the homology of the nucleotide sequence between wild bear and crossbred pig is identical in this region indicating that domestic pigs were evolved from wild boar and there was not changed in this region during the evolution processes. 相似文献
7.
Robert Müller Christoph Nowicki Wilhelm Barthlott Pierre L. Ibisch 《Biodiversity and Conservation》2003,12(10):2005-2024
Analyses of species diversity and endemism patterns provide vital inputs for conservation planning. Therefore, it is an important dilemma of biodiversity conservation that in very diverse but poorly studied tropical countries those patterns can hardly be considered. Consequently, there is an urgent need to develop prediction models that make the best use of existing data on species distribution and that can give hints on spatial conservation priorities. This paper presents the results of a pilot study on the diversity of the orchid subtribe Pleurothallidinae (331 mapped species) in the Andean rain forests of Bolivia. Results of a taxon-based mapping methodology, using abiotic (humidity and temperature, the latter indicated by altitude) and historical factors (taken into account as distance from collection localities) that determine species ranges, are compared with outcomes of an inventory-based mapping approach. The patterns of taxon-based diversity and endemism show a strong correlation with the distribution of sample localities. The inventory-based approach is more reliable, but it is interesting to apply both mapping methods in order to make a critical interpretation and comparison that facilitates some valuable conservation recommendations. We end with concrete conclusions for conservation planning and action. 相似文献
8.
Increased isolation of two Biosphere Reserves and surrounding protected areas (WAP ecological complex, West Africa) 总被引:1,自引:0,他引:1
Nicola Clerici Antonio Bodini Hugh Eva Jean-Marie Grgoire Dominique Dulieu Carlo Paolini 《Journal for Nature Conservation》2007,15(1):26-40
Protected areas such as nature reserves have been found to be effective in preventing habitat destruction and protecting ecosystems within their borders. Recent studies however found extensive loss of tropical forest habitat around protected areas, vastly contributing to increase the levels of ecological isolation. Using high-resolution satellite data we investigated the isolation trend occurring in the W-Arly-Pendjari (WAP) ecological complex in West Africa. A land-cover change analysis was performed for the period 1984–2002: savanna vegetation extension and loss were derived within the complex and in a 30 km peripheral buffer. Sample regions in the buffer were also analysed using selected spatial indicators to quantify temporal trends in habitat fragmentation. Implications for change in relative capacity to conserve biodiversity were discussed through the calculation of the species richness capacity (SRC). More than 14.5% of savanna habitat was lost in the WAP peripheral areas, while 0.3% was converted inside the complex. The degree of fragmentation of remnant savanna habitat has also drastically increased. Despite the effectiveness of the park conservation programme, we found through the SRC approach that the WAP complex is decreasing its potential capacity to conserve species richness. This process is mainly due to the rapid and extended agricultural expansion taking place around the complex. A better understanding of the ecological dynamics occurring in the peripheral regions of reserves and the consideration of development needs are key variables to achieve conservation goals in protected areas. 相似文献
9.
The conservation of poorly known species is difficult because of incomplete knowledge on their biology and distribution. We studied the contribution of two ecological niche modelling tools, the Genetic Algorithm for Rule-set Prediction (GARP) and maximum entropy (Maxent), in assessing potential ranges and distributional connectivity among 12 of the least known African and Asian viverrids. The level of agreement between GARP and Maxent predictions was low when < 15 occurrences were available, probably indicating a minimum number below that necessary to obtain models with good predictive power. Unexpectedly, our results suggested that Maxent extrapolated more than GARP in the context of small sample sizes. Predictions were overlapped with current land use and location of protected areas to estimate the conservation status of each species. Our analyses yielded range predictions generally contradicting with extents of occurrence established by the IUCN. We evidenced a high level of disturbance within predicted distributions in West and East Africa, Sumatra, and South-East Asia, and identified within West African degraded lowlands four relatively preserved areas that might be of prime importance for the conservation of rainforest taxa. Knowing whether these species of viverrids may survive in degraded or alternative habitats is of crucial importance for further conservation planning. The level of coverage of species suitable ranges by existing and proposed IUCN reserves was low, and we recommend that the total surface of protected areas be substantially increased on both continents. 相似文献
10.
Protected areas play an important role in the preservation and implementation of bold environmental agreements, among which the 20 Aichi Targets (Strategic Plan for Biodiversity 2011–2020, COP 10), with their focus on effective management systems supporting the conservation of biodiversity and eco-system services (Aichi Biodiversity Target 11). The aim of this paper is to illustrate the MEVAP (Monitoring and EValuation of Protected Areas) methodology, Italy's contribution to the topic of evaluating the effectiveness of protected areas within the international landscape (WDPA–IUCN, World Database on Protected Areas – Union for Conservation of Nature). The purpose of MEVAP is to provide a periodical review procedure as part of the process to improve the management of protected areas. Its starting point is the analysis of qualitative and quantitative data pertinent to the environmental, social and economic aspects of protected areas and to their governance.This paper illustrates the results obtained using the MEVAP method and its application to several clusters of Italian national parks. While highlighting the potential of this method, the document also proposes an initial assessment of the environmental, social and economical performance of protected areas and how performance is connected to its governance.Underpinning the study is the need to expand the use of evaluation practices and to spur scientific debate in the direction of widely spread adaptive management methods, with a view to optimising policies and management procedures and, therefore, achieving the protection targets that must be met by protected areas through their institutions. 相似文献
11.
With only five protected areas dedicated to the conservation of biodiversity (two national parks, one strict nature reserve
and two faunal reserves), Guinea has one of the smallest protected area networks in West Africa. As a result, two of the five
ecoregions of the country and six of the 14 globally threatened large and medium-sized mammals occurring in Guinea are not
found in the national protected area network. To identify areas with high biodiversity that could be included in the national
protected area network, we used the Key Biodiversity Areas (KBA) methodology. We devised a scoring system to rank the identified
KBAs according to their relative conservation significance. We identified a total of 16 KBAs throughout the country. Their
proclamation as protected areas would result in the protection of all ecoregions and all but one of Guinea’s globally threatened
large and medium-sized mammals. Twelve of the 16 KBAs have the legal status of classified forest, a status that should facilitate
the change into formal biodiversity protected areas (IUCN category I–IV). Our analysis indicates that even if only the two
areas with the highest conservation significance score, the Ziama and Diécké forests, become formal protected areas, this
would provide protection to both the western Guinean lowland forests, one of the most threatened ecoregions in Africa, and
to 11 of the 14 threatened large and medium-sized mammals occurring in Guinea. 相似文献
12.
- Sipha (Rungsia) maydis, Sipha (Rungsia) elegans, Sipha (Sipha) glyceriae and especially Sipha (Sipha) flava are considered to be virus vectors and serious pests of crops and pasture grasses. Ecological niche modelling, a useful tool for assessing potential geographical distributions of species, was used to predict the risk of invasion of these four species of the Siphini (Hemiptera, Aphididae) on a global scale.
- The maximum entropy model based on associations between unique occurrence localities and a set of environmental variables was used. Obtained models of potentially suitable habitats, based only on climatic variables, suggest that favourable conditions for each species may be present on every continent. However, S. (S.) flava appears to be potentially the most widespread species. Moreover, the resulting maps provide important information on the corridors by which invasive species are able to penetrate into new areas.
- A mean of the area under the receiver operating characteristic curve at the levels of 0.937, 0.947, 0.968, 0.937 for S. (R.) maydis, S. (R.) elegans, S. (S.) glyceriae and S. (S.) flava, respectively, indicated a high level of discriminatory power of the maximum entropy model.
- A jackknife test indicated that the precipitation of the coldest quarter with the highest gain value was the most important environmental variable restricting the expansion of the studied species.
13.
The arrival of wilderness as a policy issue, following the passing of a European Parliament resolution in 2009, has increased the profile of the issue and provided a challenge for policy-makers and practitioners. There is a need for a policy relevant definition that can guide decision-making in relation to the protection and management of wilderness areas, including their exploitation for economic benefit, and for information and data about the extent of existing wilderness and wild areas and the opportunities for its recreation. The scale of the challenge requires a high level of aspiration and any efforts will require the coordination of policy and implementation well beyond the borders of Europe itself. 相似文献
14.
根据蒙古黄芪(Astragalus membranaceus(Fisch.)Bge.var.mongholicus(Bge.)Hsiao)123个样本点数据和19个环境数据,采用4种生态位模型对蒙古黄芪在中国的潜在适生区进行综合分析,并采用受试者工作特征曲线ROC和Kappa统计量,比较不同模型的预测效果。结果显示:4个模型预测精度良好,一致性显著。AUC值均达到0.8以上,Kappa值均达到0.6以上;其中DOMAIN模型的AUC值和Kappa值均最大,说明该模型的预测精度最佳,预测结果最稳定。潜在适生区的预测结果发现,GARP模型预测的最适宜区范围最广;MAXENT和BIOCLIM模型预测结果较为相似;DOMAIN模型预测结果比较分散。4个模型预测结果均表明西北一带可以作为蒙古黄芪栽培引种的主要产区。蒙古黄芪潜在适生区主要分布于中国北纬33°以北地区;最适宜区主要分布于甘肃、宁夏、陕西、山西、河北和内蒙古等地区。 相似文献
15.
Prof. Michelangelo Minio 《Plant biosystems》2013,147(4):789-803
Abstract Correlative techniques for estimating environmental requirements of species – variably termed ecological niche modeling or species distribution modeling – are becoming very popular tools for ecologists and biogeographers in understanding diverse aspects of biodiversity. These tools, however, are frequently applied in ways that do not fit well into knowledge frameworks in population ecology and biogeography, or into the realities of sampling biodiversity over real-world landscapes. We offer 10 “fixes” – adjustments to typical methodologies that will take into account population ecological and biogeographic frameworks to produce better models. 相似文献
16.
Ephedra sinica is a rare and vulnerable species in China, and the habitat of Ephedra sinica is seriously threatened (by climate change and human activities). Predicting the suitable growth areas and constructing ecological corridors for Ephedra sinica in China will help to protect it scientifically. Based on 306 valid distribution records and 13 selected environmental factors, the maximum entropy (MaxEnt) model was used to simulate the potential current habitat zones and future (2050 and 2070) habitat zones of Ephedra sinica under four climate change scenarios. The minimum cumulative resistance (MCR) model was applied to extract important ecological corridors of Ephedra sinica. The results indicate that: (1) Under the current environment, the total area of the suitable habitat for Ephedra sinica in China is 42.24 × 105 km2, mainly distributed in Northwest China and North China. (2) Suitable area increases as the RCP rises. The center of mass of the habitat zone moved northward from Shaanxi Province to Ordos City in Inner Mongolia Autonomous Region. (3) Of the 13 environmental factors selected, the primary factor was elevation (20.8 %), followed by wettest month precipitation (18.2 %) and temperature seasonality (15.2 %). (4) Built 19 ecological corridors, with a total corridor length of 430.2 km, including seven long-distance passages and 12 short-distance corridors. All corridors are far from the artificial surface, mostly near high-altitude areas. The 19 ecological corridors constructed using the MCR model will also provide considerable importance for the survival of Ephedra sinica on a longer time scale in the future. 相似文献
17.
18.
Kim A. Medley 《Global Ecology and Biogeography》2010,19(1):122-133
Aim Niche‐based distribution models are often used to predict the spread of invasive species. These models assume niche conservation during invasion, but invasive species can have different requirements from populations in their native range for many reasons, including niche evolution. I used distribution modelling to investigate niche conservatism for the Asian tiger mosquito (Aedes albopictus Skuse) during its invasion of three continents. I also used this approach to predict areas at risk of invasion from propagules originating from invasive populations. Location Models were created for Southeast Asia, North and South America, and Europe. Methods I used maximum entropy (Maxent ) to create distribution models using occurrence data and 18 environmental datasets. One native model was created for Southeast Asia; this model was projected onto North America, South America and Europe. Three models were created independently for the non‐native ranges and projected onto the native range. Niche overlap between native and non‐native predictions was evaluated by comparing probability surfaces between models using real data and random models generated using a permutation approach. Results The native model failed to predict an entire region of occurrences in South America, approximately 20% of occurrences in North America and nearly all Italian occurrences of A. albopictus. Non‐native models poorly predict the native range, but predict additional areas at risk for invasion globally. Niche overlap metrics indicate that non‐native distributions are more similar to the native niche than a random prediction, but they are not equivalent. Multivariate analyses support modelled differences in niche characteristics among continents, and reveal important variables explaining these differences. Main conclusions The niche of A. albopictus has shifted on invaded continents relative to its native range (Southeast Asia). Statistical comparisons reveal that the niche for introduced distributions is not equivalent to the native niche. Furthermore, reciprocal models highlight the importance of controlling bi‐directional dispersal between native and non‐native distributions. 相似文献
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20.
Nesting beaches have a critical role in the life cycle of sea turtles and their survival. Many different factors affect nest site selection, ranging from the composition of the sand to the vegetation of the beach. These factors are subject to change due to the onset of climate change. We aimed to determine the possible changes in nesting beaches according to the future climate scenarios of Chelonia mydas nesting sites in the Mediterranean by ecological niche modeling. Nineteen bioclimatic variables and Representative Concentration Pathway scenarios (RCP2.6 and RCP8.5) were used to generate past, current, and future nesting site projections. The datasets were prepared with ArcGIS v10. and bioclimatic variables were analyzed using the Pearson Correlation Analysis. The ecological niche modeling was made with the MaxEnt v4.1.0. Model outputs, mean temperature of warmest quarter (22.01 %), precipitation of coldest quarter (15.32 %), mean temperature of the driest quarter (13.60 %), isothermality (12.30 %), mean diurnal range (9.22 %), the max temperature of the warmest month (6.60 %), precipitation seasonality (5.87 %) and annual mean temperature (4.73 %) are the parameters that most affect the estimated distribution of the species and the other parameters have the least effect on the estimated distribution (each < 2.60 %). The prediction accuracy of the model is measured by the Area Under the Curve (AUC) values, which is between 0 and 1, where values closer to 1 have a greater prediction accuracy. In our model results, the AUC values vary between 0.961 and 0.990. The majority of current green turtle nesting sites will continue to be suitable for nesting into the 2100′s. But the habitat suitability of the current nesting beaches in Syria and Lebanon will decrease. Conservational efforts should be developed to protect not only the current nesting beaches but also other possible nesting beaches that might become viable in the future. 相似文献