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691.
    
The Convention on Biological Diversity and the Nagoya Protocol display a broad international consensus for biodiversity conservation and equitable benefit sharing. Yet, the Aichi biodiversity targets show a lack of progress and thus indicate a need for additional action such as enhanced and better targeted financial resource mobilization. To date, no global financial burden-sharing instrument has been proposed. Developing a global-scale financial mechanism to support biodiversity conservation through intergovernmental transfers, we simulate three allocation designs: ecocentric, socioecological, and anthropocentric. We analyze the corresponding incentives needed to reach the Aichi target of terrestrial protected area coverage by 2020. Here we show that the socioecological design would provide the strongest median incentive for states which are farthest from achieving the target. Our proposal provides a novel concept for global biodiversity financing, which can serve as a starting point for more specific policy dialogues on intergovernmental burden and benefit-sharing mechanisms to halt biodiversity loss.  相似文献   
692.
    
Several studies reveal that there is a strong interconnection between climate change and biodiversity. Indeed, estimating plant biodiversity is an important issue under forest ecosystem monitoring, which allows the evaluation of carbon storage and sequestration capacity. To this end, a two‐phase strategy, suitably compatible with the most adopted sampling designs in large‐scale forest inventories, is proposed. In the first phase, tessellation stratified sampling is performed by partitioning the study area into a grid of quadrats and by randomly selecting a point in each quadrat. The first‐phase points are classified as forest or nonforest using remotely sensed imagery. In the second phase, a sample of points is selected from those classified as forest by means of simple random sampling without replacement. The second‐phase points constitute the centers of circular plots that are visited in the field to record plant species (usually trees) and their abundance. Estimators of abundance and diversity and estimators of their variances are presented. The proposed strategy is applied in a forest area from Central Italy, as a case study. With respect to the sampling effort, the resulting estimates of relative standard errors are satisfactory, especially those regarding the overall total and diversity index estimators. The proposed statistical approach represents a suitable reference for integrated forest inventory frameworks effectively supporting biodiversity monitoring and assessment.  相似文献   
693.
为了解广东省蛭态轮虫物种多样性,采集广东省不同水陆生境样品98份,记录蛭态轮虫3目4科12属66种(含亚种).陆生环境中鉴定出蛭态轮虫56种,其中苔藓生境42种、落叶生境40种、地衣生境12种,水生生境蛭态轮虫15种,陆生生境的蛭态轮虫种类明显多于水生生境蛭态轮虫.为验证形态鉴定的准确性,获取蛭态轮虫COⅠ基因序列4属16种37条,种间遗传距离8.59%~23.17%,其中楔足盘网轮虫(Adineta cuneata)和迅捷旋轮虫(Philodina rapida)的COⅠ基因序列为全球首次报道.COI基因序列中腺嘌呤(A)与胸腺嘧啶(T)的总含量(71.2%)远大于鸟嘌呤(G)与胞嘧啶(C)(28.8%)的含量.系统发育树的聚类结果与形态学物种鉴定结果一致;同属形态相近的物种,具有较高的同源性.研究结果表明,形态学鉴定与DNA条形码技术相结合,有助于提高蛭态轮虫种类鉴定的准确性和探究蛭态轮虫各属的发育地位,促进蛭态轮虫物种多样性和生态学研究.  相似文献   
694.
Tannery wastewater causes serious ecological and sanitary damage. Chemical analysis of water from Binlamdoune River of the medina of Fez was conducted and the results revealed the presence of toxic elements from tanneries and other industrial activities, which strongly a ected water quality. To determine the e ectiveness of bioremediation for depollution, we studied the abundance and diversity of bacteria residing in these polluted environments. Conducting denaturing gradient gel electrophoresis (PCR-DGGE) of the 16S rDNA area using primers related to bacteria showed a bacterial community belonging to eubacterial groups, that is, Epsilonproteobacteria, Clostridia, Lactobacillales, Bacteroidetes, Gammaproteobacteria, and Alphaproteobacteria. In addition, cloning displayed the presence of clones belonging to the Firmicutes group. Moreover, scanning electron microscopy revealed a significant heterogeneity of microorganism forms and structures. These endogenous microbes could have a significant role in the purification of Binlamdoune River and Fez tannery wastewater.  相似文献   
695.
为探究氯代脂肪烃(CAHs)污染地下水原位修复的长效性及环境的长期响应,选择华北某废弃化工厂污染区,开展了生物刺激、零价铁(ZVI)-生物刺激耦合中试对照试验,系统对比了2种修复模式下CAHs的降解效率及地下水生物化学参数的动态变化规律.结果表明,修复后长达4~5a内总CAHs含量均降至50 μg/L以下,耦合修复策略提高了CAHs的整体降解效率且未出现浓度反弹,同时可更快速地改善地下环境,为潜在降解菌的生长提供有利条件.两种修复方式对地下水细菌多样性的长期影响基本一致,均有利于向脱硫菌门Desulfobacterota和绿弯菌门Chloroflexi演化.最终生物刺激区总细菌数量高于耦合修复区约1个数量级,但后者地下水中的脱卤球菌属Dehalococcoidia数量(2.1~35)×103copies/mL反而高于前者(8.3~9.1)×103copies/mL,这更有利于CAHs的彻底脱氯.  相似文献   
696.
    
Promoting human–wildlife coexistence in complex systems where both relationships between people and toward wildlife need to be managed is challenging. We applied nonviolent communication (NVC) training as part of a participatory dialogue program to increase empathic concern toward wildlife and between people to promote human–wildlife coexistence. NVC was developed in the 1960s by Marshal Rosenberg, a clinical psychologist who sought to incorporate empathy and compassion into everyday language. Using weekly reflexive feedback from participants, we collected 36 examples of attitude change and 71 examples of behavior change that demonstrated increased empathic concern for both people and wildlife. Therefore, NVC training has potential to be an effective tool to increase empathy and promote tolerance and human–wildlife coexistence. This is the first attempt to use NVC in the biodiversity sector, and we believe these results show promise for its wider application as a tool for participatory dialogues to improve collaboration, understanding and resolve conflicts.  相似文献   
697.
    
It is nearly three decades since the world recognized the need for a global multilateral treaty aiming to address accelerating biodiversity loss. However, biodiversity continues to decline at a concerning rate. Drawing on lessons from the implementation of the current strategic plan of the Convention on Biological Diversity and the 2010 Aichi Targets, we highlight three interlinked core areas, which require attention and improvement in the development of the post-2020 Biodiversity Framework under the Convention on Biological Diversity. They are: (1) developing robust theories of change which define agreed, adaptive plans for achieving targets; (2) using models to evaluate assumptions and effectiveness of different plans and targets; and (3) identifying the common but differentiated responsibilities of different actors/states/countries within these plans. We demonstrate how future multilateral agreements must not focus only on what needs to be done but also on how it should be done, using measurable steps, which make sense at the scales at which biodiversity change happens.  相似文献   
698.
全球高致病性禽流感灾害的时空变异   总被引:2,自引:0,他引:2  
利用多种资源建立了全球高致病性禽流感灾害数据库,基于ArcGIS的空间分析和统计模块,对全球高致病性禽流感灾害的时空变异进行分析。结果表明:2003年以来全球高致病性禽流感爆发有三个流行高峰期,正好在2004和2005年的冬季;全球高致病性禽流感爆发的频率在最近几年里呈不断上升的趋势,地理空间范围不断扩散;高致病性禽流感的爆发在时间和空间上表现得更加集中。全球高致病性禽流感分布的总体特征表明在家禽密度高的区域,邻近家禽生产地的湖泊和水库附近,或者鸟类迁徒路线的交叉处,特别是那些重叠的区域可能是高致病性禽流感的多发地区。上述结果可为高致病性禽流感灾害的防控提供借鉴和依据。  相似文献   
699.
采用微宇宙培养法,模拟微污染景观水体富营养化过程,研究其浮游藻类演替状况及生物多样性指数.结果表明,最终优势藻种为黄藻门.通过计算9种生物多样性指数(Margalefs、PIE(种间相遇几率)、Menhinicks、Shannon-Wiener、Simpsons、McNaughtonsdominanceindex、Species、OD(多样性测度指数)、Monk)对景观水体富营养化过程中浮游植物演替趋势进行评价,发现其中仅2种多样性指数适于静态景观水体富营养化研究,分别为Monk多样性指数及Menhinicks多样性指数,而其它指数都不够准确.  相似文献   
700.
The effect of lime and ash additions upon the below ground ectomycorrhizal communities was studied at two spruce forest sites, Horröd and Hasslöv, in Southern Sweden. At Hasslöv, fifteen years after the addition of 8.75 ton ha-1 of dolomite, the species richness of the mycorrhizal community was unchanged. However, the liming resulted in an almost total replacement of species normally found under the site conditions, with only three morphotypes from a total of 24 distinguished being common to both the control and limed plots. At Horröd, four years after the application of 3.25 ton ha-1 crushed lime, there was a significant reduction in the number of species recorded. This was not a result of a reduction in root tips sampled, since there was no significant treatment effect upon root tip abundance. Instead, it appeared that the less common species present in the control plots had been lost following liming. At the same site, the addition of 4.28 ton ha-1 of wood ash had little effect upon the mycorrhizal community as a whole, with only small changes recorded in the abundance of a small number of species. This study highlights the urgent need for additional data on the temporal and load response of ectomycorrhizal fungi to the addition of lime. This information is vital in view of the proposed widespread use of lime as a counter measure to soil acidification.  相似文献   
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