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141.
CHARLOTTE MURRAY-SMITH‡ NEIL A. BRUMMITT ARY T. OLIVEIRA-FILHO† STEVEN BACHMAN JUSTIN MOAT EIMEAR M. NIC LUGHADHA EVE J. LUCAS§ 《Conservation biology》2009,23(1):151-163
Abstract: Plant-diversity hotspots on a global scale are well established, but smaller local hotspots within these must be identified for effective conservation of plants at the global and local scales. We used the distributions of endemic and endemic-threatened species of Myrtaceae to indicate areas of plant diversity and conservation importance within the Atlantic coastal forests ( Mata Atlântica ) of Brazil. We applied 3 simple, inexpensive geographic information system (GIS) techniques to a herbarium specimen database: predictive species-distribution modeling (Maxent); complementarity analysis (DIVA-GIS); and mapping of herbarium specimen collection locations. We also considered collecting intensity, which is an inherent limitation of use of natural history records for biodiversity studies. Two separate areas of endemism were evident: the Serra do Mar mountain range from Paraná to Rio de Janeiro and the coastal forests of northern Espírito Santo and southern Bahia. We identified 12 areas of approximately 35 km2 each as priority areas for conservation. These areas had the highest species richness and were highly threatened by urban and agricultural expansion. Observed species occurrences, species occurrences predicted from the model, and results of our complementarity analysis were congruent in identifying those areas with the most endemic species. These areas were then prioritized for conservation importance by comparing ecological data for each. 相似文献
142.
FINN DANIELSEN HENDRIEN BEUKEMA† NEIL D. BURGESS‡§ FAIZAL PARISH CARSTEN A. BRÜHL†† PAUL F. DONALD‡‡ DANIEL MURDIYARSO§§ BEN PHALAN‡ LUCAS REIJNDERS MATTHEW STRUEBIG††† EMILY B. FITZHERBERT‡‡‡§§§ 《Conservation biology》2009,23(2):348-358
Abstract: The growing demand for biofuels is promoting the expansion of a number of agricultural commodities, including oil palm (Elaeis guineensis). Oil‐palm plantations cover over 13 million ha, primarily in Southeast Asia, where they have directly or indirectly replaced tropical rainforest. We explored the impact of the spread of oil‐palm plantations on greenhouse gas emission and biodiversity. We assessed changes in carbon stocks with changing land use and compared this with the amount of fossil‐fuel carbon emission avoided through its replacement by biofuel carbon. We estimated it would take between 75 and 93 years for the carbon emissions saved through use of biofuel to compensate for the carbon lost through forest conversion, depending on how the forest was cleared. If the original habitat was peatland, carbon balance would take more than 600 years. Conversely, planting oil palms on degraded grassland would lead to a net removal of carbon within 10 years. These estimates have associated uncertainty, but their magnitude and relative proportions seem credible. We carried out a meta‐analysis of published faunal studies that compared forest with oil palm. We found that plantations supported species‐poor communities containing few forest species. Because no published data on flora were available, we present results from our sampling of plants in oil palm and forest plots in Indonesia. Although the species richness of pteridophytes was higher in plantations, they held few forest species. Trees, lianas, epiphytic orchids, and indigenous palms were wholly absent from oil‐palm plantations. The majority of individual plants and animals in oil‐palm plantations belonged to a small number of generalist species of low conservation concern. As countries strive to meet obligations to reduce carbon emissions under one international agreement (Kyoto Protocol), they may not only fail to meet their obligations under another (Convention on Biological Diversity) but may actually hasten global climate change. Reducing deforestation is likely to represent a more effective climate‐change mitigation strategy than converting forest for biofuel production, and it may help nations meet their international commitments to reduce biodiversity loss. 相似文献
143.
ROBIN L. CHAZDON CARLOS A. PERES DAISY DENT DOUGLAS SHEIL ARIEL E. LUGO DAVID LAMB NIGEL E. STORK SCOTT E. MILLER 《Conservation biology》2009,23(6):1406-1417
Abstract: In the wake of widespread loss of old‐growth forests throughout the tropics, secondary forests will likely play a growing role in the conservation of forest biodiversity. We considered a complex hierarchy of factors that interact in space and time to determine the conservation potential of tropical secondary forests. Beyond the characteristics of local forest patches, spatial and temporal landscape dynamics influence the establishment, species composition, and persistence of secondary forests. Prospects for conservation of old‐growth species in secondary forests are maximized in regions where the ratio of secondary to old‐growth forest area is relatively low, older secondary forests have persisted, anthropogenic disturbance after abandonment is relatively low, seed‐dispersing fauna are present, and old‐growth forests are close to abandoned sites. The conservation value of a secondary forest is expected to increase over time, as species arriving from remaining old‐growth forest patches accumulate. Many studies are poorly replicated, which limits robust assessments of the number and abundance of old‐growth species present in secondary forests. Older secondary forests are not often studied and few long‐term studies are conducted in secondary forests. Available data indicate that both old‐growth and second‐growth forests are important to the persistence of forest species in tropical, human‐modified landscapes. 相似文献
144.
Johann Baumgärtner Josef Hartmann 《Journal of Agricultural and Environmental Ethics》2001,14(1):67-83
The paper describes the design and implementation of a plant biodiversity conservation program that was developed under funding and time constraints for diverse ecological, social, and institutional environments. The biodiversity program for alpine meadows and pastures located in the Swiss Canton of the Grisons is used as an example. The design of the sustainable program relied on existing legislation, accounted for limited ecological knowledge and expertise, and considered biodiversity as a common-pool resource. The trend to intensified cultivation of restricted areas required fast action, while the sustainability of the program design had to take into account institutional diversity. Fifteen habitats and plant communities worth conserving were known, and 57 plant species were identified as indicator species for establishing an inventory and for monitoring purposes. A small subset of 16 well known plant species was presented to the farming communities. They were invited to notify the areas in which they observed the presence of these plants. In different regions of the Canton a total number of 39 paraecologists were trained to inspect the areas notified by farmers and to recommend possible incorporation into the Cantonal inventory. This was done once the farmers signed a contract in which they agreed to follow adequate management practices. The farmers received subsidies to compensate for their losses. Communal authorities controlled the fertilizer input and cutting dates, while the paraecologists were trained to monitor plant biodiversity. The program started in 1992 and the initial phase of the inventory was terminated in 1996. At the beginning of 1996, an inventory of 2617.19 ha, most of which are meadows, was taken and managed according to the rules specified in the contract. The program was considered successful because (i) of the size of the area in the inventory, (ii) about 30%of the farmers participated, and (iii) farmers started cultivating previously abandoned farmland. 相似文献
145.
The cause-and-effect relationships existing in freshwater biogeocenoses and changing with time are conventionally divided into three groups: direct, directly mediated, and indirect. The possibility of using the indirect relationships for the control over natural systems is exemplified by a new scheme of eutrophication control and water quality improvement. 相似文献
146.
西部大开发中的生物多样性的保护 总被引:5,自引:2,他引:3
全球的生物物种在急剧减少,而此情景也呈现于我国的西部在,在机遇与挑战同在的西部大开发过程中如何切实效保护生物多样性,无疑已成为我们必须关注和思考的问题。本文从生物多样性的内涵、生物多样性的价值、生物多样性的丧失及保护生物多样性的必要性及对策等方面,论述笔者对预防、保护、恢复生物多样性的几点思考,但愿能引起广大社会的关注和支持。 相似文献
147.
The Economic Consequences of Alien Plant Invasions: Examples of Impacts and Approaches to Sustainable Management in South Africa 总被引:2,自引:1,他引:1
B.W. van Wilgen D.M. Richardson D.C. Le Maitre C. Marais D. Magadlela 《Environment, Development and Sustainability》2001,3(2):145-168
The invasion of natural ecosystems by alien plants is a serious environmental problem that threatens the sustainable use of benefits derived from such ecosytems. Most past studies in this field have focussed on the history, ecology and management of invasive alien species, and little work has been done on the economic aspects and consequences of invasions. This paper reviews what is known of the economic consequences of alien plant invasions in South Africa. These economic arguments have been used to successfully launch the largest environmental management programme in Africa.Ten million hectares of South Africa has been invaded by 180 alien species, but their impacts are not fully understood, although they are undoubtedly significant. The indications are that the total costs of these impacts are substantial. Selected studies show that invasions have reduced the value of fynbos ecosystems by over US$ 11.75 billion; that the total cost of invasion would be about US$ 3.2 billion on the Agulhas Plain alone; that the net present cost of invasion by black wattles amounts to US$ 1.4 billion; that invasions by red water fern have cost US$ 58 million; and that the cost to clear the alien plant invasions in South Africa is around US$ 1.2 billion. These few examples indicate that the economic consequences of invasions are huge.One of the unique aspects of invasive plant control programmes in South Africa has been the ability to leverage further benefits (mainly through employment) for the expensive control programmes from the government's poverty relief budget. This has made it possible to allocate substantial funding to a programme that would otherwise have struggled to obtain significant support. Biological control of invasive species also offers considerable benefits, but is often the subject of debate. We believe that, at least in the case of many invasive alien plant species in South Africa, biological control offers one of the best, and most cost-effective, interventions for addressing the problem. 相似文献
148.
地球是一个具有一定自洁、自我修复功能的大生态系统,它由各种植物、动物、人类、微生物有机的组成,维持着自然界的生态平衡。而大量的人类活动给地球的生态平衡产生了较大影响,特别是明显加快的城市化进程,使得这种平衡逐渐受到不可逆的破坏。论文重点分析了城市化给生态平衡所带来的问题,并由此提出了从生物链的角度建立生物资源平衡,从而实现新的生态平衡。将城市污染物的资源化和生态平衡联系起来,通过建立生物资源补充机制、改变城市垃圾和污水的处理方法等措施,促进生物资源平衡,在相对较大的范围内实现人类发展与自然相协调,实现可持续发展。 相似文献
149.
MAYEUL DALLEAU SERGE ANDRÉFOUËT COLETTE C.C. WABNITZ CLAUDE PAYRI LAURENT WANTIEZ MICHEL PICHON KIM FRIEDMAN LAURENT VIGLIOLA FRANCESCA BENZONI 《Conservation biology》2010,24(2):541-552
Abstract: Marine protected areas (MPAs) have been highlighted as a means toward effective conservation of coral reefs. New strategies are required to more effectively select MPA locations and increase the pace of their implementation. Many criteria exist to design MPA networks, but generally, it is recommended that networks conserve a diversity of species selected for, among other attributes, their representativeness, rarity, or endemicity. Because knowledge of species’ spatial distribution remains scarce, efficient surrogates are urgently needed. We used five different levels of habitat maps and six spatial scales of analysis to identify under which circumstances habitat data used to design MPA networks for Wallis Island provided better representation of species than random choice alone. Protected‐area site selections were derived from a rarity–complementarity algorithm. Habitat surrogacy was tested for commercial fish species, all fish species, commercially harvested invertebrates, corals, and algae species. Efficiency of habitat surrogacy varied by species group, type of habitat map, and spatial scale of analysis. Maps with the highest habitat thematic complexity provided better surrogates than simpler maps and were more robust to changes in spatial scales. Surrogates were most efficient for commercial fishes, corals, and algae but not for commercial invertebrates. Conversely, other measurements of species‐habitat associations, such as richness congruence and composition similarities provided weak results. We provide, in part, a habitat‐mapping methodology for designation of MPAs for Pacific Ocean islands that are characterized by habitat zonations similar to Wallis. Given the increasing availability and affordability of space‐borne imagery to map habitats, our approach could appreciably facilitate and improve current approaches to coral reef conservation and enhance MPA implementation. 相似文献
150.
基于高通量测序分析的生物修复石油污染土壤菌群结构变化 总被引:2,自引:1,他引:2
利用高通量测序技术对微生物修复石油污染土壤过程中的微生物群落结构变化进行研究.结果表明,经修复处理的土壤微生物群落结构及多样性发生明显变化.利用生物强化修复处理(BA)的土壤中,微生物丰富度与均匀度明显降低,土著菌群受到抑制,外加变形菌门(Proteobacteria)成为主要的优势菌门,相对丰度由修复前的37. 44%增加为87. 44%.假单胞菌属(Pseudomonas)成为土壤中的优势菌属,丰度由2. 99%增加为76. 37%;进行生物刺激修复处理的土壤(BS)菌群丰富度和均匀度与原污染土壤相比略有降低.菌群结构组成上,原优势菌门变形菌门(Proteobacteria)丰度由37. 44%降低为10. 90%,厚壁菌门(Firmicutes)丰度由9. 16%增加为35. 32%,属水平上,原优势菌属微小杆菌属(Exiguobacterium)和原小单胞菌属(Promicromonospora)丰度由8. 49%和18. 96%分别降低为2. 19%和14. 97%,诺卡氏菌属(Nocardioides)和芽孢杆菌属(Bacillus)丰度由5. 56%和0. 29%分别增加至28. 95%和22. 70%,成为主要优势菌属.生物强化修复处理引起土壤菌群多样性和结构发生明显变化,生物刺激修复处理可基本保持土壤菌群结构多样性不被破坏,土壤菌群结构的稳定有利于石油烃的生物降解. 相似文献