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Mathew J. Hardy James A. Fitzsimons Sarah A. Bekessy Ascelin Gordon 《Conservation biology》2018,32(2):276-286
Finding sustainable ways to increase the amount of private land protected for biodiversity is challenging for many conservation organizations. In some countries, organizations use revolving‐fund programs, whereby land is purchased and then sold to conservation‐minded owners under condition they enter into a conservation covenant or easement. The sale proceeds are used to purchase, protect, and sell additional properties, incrementally increasing the amount of protected private land. Because the effectiveness of this approach relies on selecting appropriate properties, we explored factors currently considered by practitioners and how these are integrated into decision making. We conducted exploratory, semistructured interviews with managers from each of the 5 major revolving funds in Australia. Responses indicated although conservation factors are important, financial and social factors are also highly influential. A major determinant was whether the property could be resold within a reasonable period at a price that replenishes the fund. To facilitate resale, often selected properties include the potential for the construction of a dwelling. Practitioners face with clear trade‐offs between conservation, financial, amenity, and other factors in selecting properties and 3 main challenges: recovering the costs of acquisition, protection, and resale; reselling the property; and meeting conservation goals. Our findings suggest the complexity of these decisions may constrain revolving‐fund effectiveness. Drawing from participant responses, we identified potential strategies to mitigate these risks, such as providing adequate recreational space without jeopardizing ecological assets. We suggest managers could benefit from a shared‐learning and adaptive approach to property selection given the commonalities between programs. Understanding how practitioners deal with complex decisions in the implementation of revolving funds helps identify future research to improve the performance of this conservation tool. 相似文献
153.
Fungi are undoubtedly important for ecosystem functioning; however, they have been omitted or given scant attention in most biodiversity policy documents, management plans, and formal conservation schedules throughout the world. This oversight may be due to a general lack of awareness in the scientific community and compounded by a scarcity of mycology‐associated curricula at the tertiary level and a lack of mycologists in research institutions. Although molecular techniques advance the systematic cataloging of fungi and facilitate insights into fungal communities, the scarcity of professional mycologists in the environmental sciences hampers conservation efforts. Conversely, citizen science initiatives are making significant contributions to the mycology discipline by increasing awareness and extending the scope of fungal surveys. Future research by professional and amateur mycologists into the distribution of fungi and their function in ecosystems will help identify wider and more effective conservation goals. 相似文献
154.
Use of genetic,climatic, and microbiological data to inform reintroduction of a regionally extinct butterfly 下载免费PDF全文
Vlad Dincă Zsolt Bálint Raluca Vodă Leonardo Dapporto Paul D. N. Hebert Roger Vila 《Conservation biology》2018,32(4):828-837
Species reintroductions are increasingly used as means of mitigating biodiversity loss. Besides habitat quality at the site targeted for reintroduction, the choice of source population can be critical for success. The butterfly Melanargia russiae (Esper´s marbled white) was extirpated from Hungary over 100 years ago, and a reintroduction program has recently been approved. We used museum specimens of this butterfly, mitochondrial DNA data (mtDNA), endosymbiont screening, and climatic‐similarity analyses to determine which extant populations should be used for its reintroduction. The species displayed 2 main mtDNA lineages across its range: 1 restricted to Iberia and southern France (Iberian lineage) and another found throughout the rest of its range (Eurasian lineage). These 2 lineages possessed highly divergent wsp alleles of the bacterial endosymbiont Wolbachia. The century‐old Hungarian specimens represented an endemic haplotype belonging to the Eurasian lineage, differing by one mutation from the Balkan and eastern European populations. The Hungarian populations of M. russiae occurred in areas with a colder and drier climate relative to most sites with extant known populations. Our results suggest the populations used for reintroduction to Hungary should belong to the Eurasian lineage, preferably from eastern Ukraine (genetically close and living in areas with the highest climatic similarity). Materials stored in museum collections can provide unique opportunities to document historical genetic diversity and help direct conservation. 相似文献
155.
The Global Strategy for Plant Conservation (GSPC) set an ambitious target to achieve a conservation assessment for all known plant species by 2020. We consolidated digitally available plant conservation assessments and reconciled their scientific names and assessment status to predefined standards to provide a quantitative measure of progress toward this target. The 241,919 plant conservation assessments generated represent 111,824 accepted land plant species (vascular plants and bryophytes, not algae). At least 73,081 and up to 90,321 species have been assessed at the global scale, representing 21–26% of known plant species. Of these plant species, at least 27,148 and up to 32,542 are threatened. Eighty plant families, including some of the largest, such as Asteraceae, Orchidaceae, and Rubiaceae, are underassessed and should be the focus of assessment effort if the GSPC target is to be met by 2020. Our data set is accessible online (ThreatSearch) and is a baseline that can be used to directly support other GSPC targets and plant conservation action. Although around one‐quarter of a million plant assessments have been compiled, the majority of plants are still unassessed. The challenge now is to build on this progress and redouble efforts to document conservation status of unassessed plants to better inform conservation decisions and conserve the most threatened species. 相似文献
156.
稻田甲烷排放通量与农业管理措施的关系 总被引:1,自引:0,他引:1
邵可声 《生态与农村环境学报》1993,(Z1)
1990至1992年对北京地区的麦后稻区及单季稻区进行了三年的稻田甲烷排放通量的测定,麦后稻区的甲烷排放通量约17.5mg/m~2·h;单季稻小区约在8.5-10mg/m~2·h。有机底肥的用量是影响甲烷排放通量的首要因素,旱直播及仅使用化肥可降低甲烷排放通量。在一定量有机底肥的条件下,采用间歇灌溉的方法既可保持或提高水稻的产量,又可抑制或降低甲烷的排放通量,但也观测到干干湿湿的状态下温室气体N_2O的排放通量有所增加。 相似文献
157.
低压离子色谱法测定水和酸雨样品中的Li~+,Na~+,NH_4~+,K~+,Ca~(2+)和Mg~(2+)离子 总被引:3,自引:0,他引:3
本文介绍了低压离子色谱仪测定水样(井水、湖水、矿泉水、自来水)和酸雨中锂、钠、铵、钙、钾和镁离子的方法、欲测阳离子在阳离子交换柱上被分离,分别用1.4mmol·1~(-1)HNO_3和0.6mmol·1~(-1)乙二胺+1.2mmol·1~(-1)HNO_3溶液作流动相,流速为1.6ml·min~(-1).各离子的流分用电导检测.进样量为10μl时,Li~+,Na~+,NH_4~+,K~+,Ca~(2+)和Mg~(2+)离子的检出限(2倍噪音比),分别为0.020,0.050,0.100,0.250,2.5和1.0μg·ml~(-1). 相似文献
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159.
孟范平 《生态与农村环境学报》1994,(4)
根据C_3植物和C_4植物对高浓度CO_2的不同反应,评述了富CO_2大气对生态系统的影响。结论是大气CO_2浓度增加将导致生态系统发生一系列变化,包括生物多样世的减少、营养循环受阻、虫灾发生和温室效应加剧等。 相似文献
160.