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91.
We propose the wildlife premium mechanism as an innovation to conserve endangered large vertebrates. The performance‐based payment scheme would allow stakeholders in lower‐income countries to generate revenue by recovering and maintaining threatened fauna that can also serve as umbrella species (i.e., species whose protection benefits other species with which they co‐occur). There are 3 possible options for applying the premium: option 1, embed premiums in a carbon payment; option 2, link premiums to a related carbon payment, but as independent and legally separate transactions; option 3, link premiums to noncarbon payments for conserving ecosystem services (PES). Each option presents advantages, such as incentive payments to improve livelihoods of rural poor who reside in or near areas harboring umbrella species, and challenges, such as the establishment of a subnational carbon credit scheme. In Kenya, Peru, and Nepal pilot premium projects are now underway or being finalized that largely follow option 1. The Kasigau (Kenya) project is the first voluntary carbon credit project to win approval from the 2 leading groups sanctioning such protocols and has already sold carbon credits totaling over $1.2 million since June 2011. A portion of the earnings is divided among community landowners and projects that support community members and has added over 350 jobs to the local economy. All 3 projects involve extensive community management because they occur on lands where locals hold the title or have a long‐term lease from the government. The monitoring, reporting, and verification required to make premium payments credible to investors include transparent methods for collecting data on key indices by trained community members and verification of their reporting by a biologist. A wildlife premium readiness fund would enable expansion of pilot programs needed to test options beyond those presented here. Mejora de la Conservación, Servicios del Ecosistema y Calidad de Vida Local Mediante un Mecanismo de Compensación de Vida Silvestre  相似文献   
92.
Data on the abundance and occurrence of 64 odonate species in the Southern Urals are considered. A comparative analysis of the odonate fauna in the early 20th century, in the 1960s and 1970s, and in the early 21st century is performed. On this basis, it is concluded that its structure has been markedly changing with time, with the magnitude of these changes being comparable to that of regional faunistic differences. The causes of these changes are discussed. The apparent enrichment of the odonate fauna is attributed primarily to the appearance of new anthropogenic habitats.  相似文献   
93.
Multivariate analysis of variance, canonical correlation and canonical discriminate analysis were performed on environmental data collected from the Kuwaiti intertidal zone to determine the statistical relationships between the sediment, chemical, biological, spatial and temporal variables. The quantitative analysis showed that the sediment type was the paramount factor influencing the distribution and composition of the intertidal benthic fauna. The muddy, sandy and rocky shores support three distinct faunal communities. The seasonal variation in the benthic fauna community was not statistically significant but variation in biological data due to differences in transect location and tidal level were significant. This spatial variation has been attributed to differences in sediment and substrate types. The physico-chemical parameters were found to correlate positively with the mud content of the sediments but were unimportant in the overall composition of the intertidal fauna. This paper complements the results reported in Al Bakriet al. (1997–Part I) in establishing a valuable benchmark for assessing environmental impacts and for developing sustainable coastal zone management in Kuwait. The integrated approach outlined here could be adopted to develop a sound basis for the protection and management of coastal environments and resources in similar areas.  相似文献   
94.
据对有较详细分布资料的206种祝蛾科昆虫分析,中国祝蛾科昆虫其区系组成以广布种占多数,共计62种,占30.1%,东洋界55种,占26.7%.在中国动物地理区划中,华中、华南、西南三区分布的种占所采总数的60.4%,可见此三区关系较为密切.表3,参6.  相似文献   
95.
报道了长沙市区危害房屋及园林树木的白蚁种类及危害状况,经5年调查(2000年-2004年)结果表明:长沙市(不包括长、望、浏、宁四县)共有白蚁2科17种.主要危害房屋的为散白蚁及台湾乳白蚁,危害园林树木的是黑翅土白蚁及黄翅大白蚁.讨论了区系特点及近年危害新状况。  相似文献   
96.
氮沉降下鼎湖山森林凋落物分解及与土壤动物的关系   总被引:12,自引:0,他引:12  
研究了南亚热带3种森林生态系统凋落物在N沉降下的分解动态及其与土壤动物群落的关系。选取季风常绿阔叶林、针阔混交林和马尾松林建立野外模拟N沉降样地,实施四个处理组,对照(Control)、低氮(50kg·hm-2·a-1,LowN)、中氮(100kg·hm-2·a-1,MediujmN)和高氮处理(150kg·hm-2·a-1,HighN),利用凋落物网袋法,在18个月的时间内调查分析了凋落物分解过程及其中的土壤动物密度特征。研究结果表明,植被演替阶段对凋落物的分解速度存在影响,季风林凋落物降解速度显著性快于混交林和针叶林(P<0.05);18个月后,季风林各处理地凋落物残留率为0.05、0.14、0.13和0.17,混交林为0.64、0.56和0.62,针叶林为0.66、0.63和0.62。N沉降增加对凋落物分解存在一定影响。且这种影响与植被类型之间存在明显的交互作用。N沉降处理对季风林凋落物分解表现出了一定的抑制作用,而且这种差异随时间推移愈益明显,但在混交林和针叶林内,试验后期凋落物分解受到了N沉降处理的促进作用。在试验后期,尤其是12个月后,凋落物网袋土壤动物密度在不同林地和不同水平N处理下体现了差异化发展趋势。在季风林内,N处理地土壤动物密度受到了明显的抑制;在混交林和针叶林内,低N样地动物密度显示了相比对照样地的明显优势,但在较高强度的中N处理地无论在凋落物的降解速率还是在动物密度上都与对照样地没有明显差别。文章认为,N沉降处理所产生的影响可能受环境N饱和程度的调控。文章还提出,在凋落物分解进程中,土壤动物群落具有“后期进入”特征,这对于进一步准确分析森林凋落物分解进程及土壤动物的贡献有重要意义。  相似文献   
97.
选择贵州花江喀斯特峡谷为研究区,于2009年5月和9月对不同等级石漠化地的土壤动物多样性和花椒凋落物的分解速率进行研究。共获土壤动物3423只,隶属于3门7纲19目,共21个类群,优势类群为弹尾目(Collembola)、甲螨亚目(Oribatida)、中气门亚目(Mesostigmata);常见类群为前气门亚目(Prostigmata)、鞘翅目(Coleoptera)、双翅目(Diptera)、膜翅目(Hymenoptera)、半翅目(Hemiptera)。研究结果表明:(1)减少人为活动、有效保存地面凋落物、提高生境生物多样性可以迅速改良土壤生态环境,有效恢复土壤动物群落;(2)凋落物分解受土壤动物数量的影响最大,尤其是弹尾目和蜱螨目的数量起决定作用;(3)石漠化治理工程对花江石漠化治理和喀斯特生态环境的重建具有重要意义。  相似文献   
98.
于2010年8~10月对滇池白山湾人工控制性种养的约70hm2的水葫芦区、近水葫芦区和远水葫芦区采样分析,探讨了水葫芦种养工程区域内外底栖动物群落结构特征.结果表明,在水葫芦区、近水葫芦区及远水葫芦区,底栖动物总密度分别为294.5,159,261ind/m2,其中寡毛类的霍甫水丝蚓(Limnodrilus hoffmeisteri)为绝对优势种,分别占各自区域总密度的68.3%,59.6%和86.0%.逐步回归分析显示,水体总磷(TP)和底泥非稳定态磷(Labile-P)与霍甫水丝蚓密度呈显著性正相关(P < 0.01),表明霍甫水丝蚓对水体的富营养状况有很好的指示作用.水葫芦区物种组成及生物多样性指数均高于近水葫芦区和远水葫芦区(P < 0.05),在水葫芦区、近水葫芦区和远水葫芦区分别共采集到底栖动物14种、10种和6种;Shannon-Wiener多样性指数分别为1.10,0.57和0.54.种植水葫芦后,在水葫芦区及近水葫芦区,10月份的Margalef、Shannon-Wiener、Simpson和Peilou指数较8月份和9月份有显著性增加(P < 0.05),而远水葫芦区,却未出现类似的结果.一定面积控制性种养水葫芦对大型富营养化湖湾水体无脊椎底栖动物群落结构未表现出不利影响.  相似文献   
99.
Mercury (Hg) is a ubiquitous environmental toxin that produces a wide range of adverse health effects in humans. Bioaccumulation of mercury in the aquatic food chain is a public concern for many countries. The aim of this study was to review the prevalence of Hg contamination in marine fauna in Thailand.  相似文献   
100.
Plastics debris is known to be present in all of the world's oceans, and on most amenity beaches, although comparatively little data are available to provide reliable information on the extent of damage from this pollution, and on its spatial and temporal variations.

Marine pollution by plastics has been shown to be damaging to marine mammals, birds and reptiles. This is due to entanglement in packaging bands, synthetic ropes and lines, or drift nets; or by the ingestion of small items of plastics debris. More research is needed to quantify the extent of the problems.

Wider use of degradable plastics will not solve the problems of plastics pollution. Their lifetimes are relatively long and unpredictable, and they are not generally acceptable for recycling.

Marine plastics pollution may be alleviated by the judicious application of both economic incentives and legislation, designed to decrease their use, to increase the rate of recycling, and to restrict uncontrolled discards.  相似文献   
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