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921.
C. Wyborn J. Montana N. Kalas S. Clement F. Davila N. Knowles E. Louder M. Balan J. Chambers L. Christel T. Forsyth G. Henderson S. Izquierdo Tort M. Lim M. J. Martinez-Harms J. Merçon E. Nuesiri L. Pereira V. Pilbeam E. Turnhout S. Wood M. Ryan 《Conservation biology》2021,35(4):1086-1097
Decades of research and policy interventions on biodiversity have insufficiently addressed the dual issues of biodiversity degradation and social justice. New approaches are therefore needed. We devised a research and action agenda that calls for a collective task of revisiting biodiversity toward the goal of sustaining diverse and just futures for life on Earth. Revisiting biodiversity involves critically reflecting on past and present research, policy, and practice concerning biodiversity to inspire creative thinking about the future. The agenda was developed through a 2-year dialogue process that involved close to 300 experts from diverse disciplines and locations. This process was informed by social science insights that show biodiversity research and action is underpinned by choices about how problems are conceptualized. Recognizing knowledge, action, and ethics as inseparable, we synthesized a set of principles that help navigate the task of revisiting biodiversity. The agenda articulates 4 thematic areas for future research. First, researchers need to revisit biodiversity narratives by challenging conceptualizations that exclude diversity and entrench the separation of humans, cultures, economies, and societies from nature. Second, researchers should focus on the relationships between the Anthropocene, biodiversity, and culture by considering humanity and biodiversity as tied together in specific contexts. Third, researchers should focus on nature and economies by better accounting for the interacting structures of economic and financial systems as core drivers of biodiversity loss. Finally, researchers should enable transformative biodiversity research and action by reconfiguring relationships between human and nonhuman communities in and through science, policy, and practice. Revisiting biodiversity necessitates a renewed focus on dialogue among biodiversity communities and beyond that critically reflects on the past to channel research and action toward fostering just and diverse futures for human and nonhuman life on Earth. 相似文献
922.
923.
南四湖新薛河湖滨带湿地修复效果评价 总被引:1,自引:0,他引:1
通过对南水北调东线南四湖新薛河入湖口湖滨带人工湿地修复区的植物群落组成和物种多样性进行调查,采用Shannon-Wiener指数、Simpson指数、均匀度指数和丰富度指数对该地区的植物物种多样性进行分析,以评价退耕还湿措施对湖滨带退化湿地的生态修复效果.结果表明,经过2年的生态修复工作,湖滨带退化湿地中的植物物种数量由修复前的16科25种提高到修复后的24科47种.修复后的湖滨带湿地生态系统具有较高的生物多样性,其物种多样性明显高于未修复地区,其中,修复后的湿地高位台田区Shannon-Wiener指数、Simpson指数、均匀度指数分别为1.619、0.745和0.860,远高于未修复高位台田区的0.060、0.012和0.065.通过退耕还湿措施修复的湖滨带人工湿地系统对于恢复南四湖湿地的物种多样性、实现湖滨带湿地生态系统的自然可持续性具有重要的意义. 相似文献
924.
Value of Small Patches in the Conservation of Plant-Species Diversity in Highly Fragmented Rainforest 总被引:2,自引:0,他引:2
VÍCTOR ARROYO-RODRÍGUEZ†‡ EDUARDO PINEDA FEDERICO ESCOBAR JULIETA BENÍTEZ-MALVIDO† 《Conservation biology》2009,23(3):729-739
Abstract: We evaluated the importance of small (<5 ha) forest patches for the conservation of regional plant diversity in the tropical rainforest of Los Tuxtlas, Mexico. We analyzed the density of plant species (number of species per 0.1 ha) in 45 forest patches of different sizes (1–700 ha) in 3 landscapes with different deforestation levels (4, 11, and 24% forest cover). Most of the 364 species sampled (360 species, 99%) were native to the region, and only 4 (1%) were human-introduced species. Species density in the smallest patches was high and variable; the highest (84 species) and lowest (23 species) number of species were recorded in patches of up to 1.8 ha. Despite the small size of these patches, they contained diverse communities of native plants, including endangered and economically important species. The relationship between species density and area was significantly different among the landscapes, with a significant positive slope only in the landscape with the highest deforestation level. This indicates that species density in a patch of a given size may vary among landscapes that have different deforestation levels. Therefore, the conservation value of a patch depends on the total forest cover remaining in the landscape. Our findings revealed, however, that a great portion of regional plant diversity was located in very small forest patches (<5 ha), most of the species were restricted to only a few patches (41% of the species sampled were distributed in only 1–2 patches, and almost 70% were distributed in 5 patches) and each landscape conserved a unique plant assemblage. The conservation and restoration of small patches is therefore necessary to effectively preserve the plant diversity of this strongly deforested and unique Neotropical region. 相似文献
925.
Very few studies have investigated the effect of genetic diversity on the behavioral and phenotypic traits linked to the competitive
ability of individuals. In this study, we reared juvenile Atlantic salmon (Salmo salar) alone or with the competitive rainbow trout (Oncorhynchus mykiss) in order to: (1) to assess correlations between heterozygosity and traits related to individual competitive ability [i.e.,
heterozygosity–fitness correlations (HFCs)] in Atlantic salmon, and (2) to evaluate the effect of the competitive rainbow
trout on any such HFCs. We also tested whether a few loci had a disproportionately large effect (i.e., the local effect hypothesis)
or, on the contrary, if all loci contributed equally (i.e., the global effect hypothesis) in explaining the observed HFCs.
We found significant HFCs for phenotypic traits related to the competitive ability of juvenile Atlantic salmon, i.e., the
growth rate and the distance to the feeding source. Some HFCs were nonlinear, suggesting that individuals with intermediate
levels of heterozygosity were favored. In addition, we found that the competition exerted by rainbow trout only weakly modified
these HFCs as the relationships were highly consistent across treatments. We demonstrated that the local-effect hypothesis
best explained both linear and nonlinear HFCs. Overall, our results illustrated the importance of genetic diversity in explaining
the behavioral variability observed within populations. Moreover, we provide evidence that, even if a competitive species
can have strong ecological effects, the relationships between genetic diversity and fitness-related traits in juvenile Atlantic
salmon were not influenced by such effects. 相似文献
926.
黄土高原土壤中细菌群落结构多样性的PCR-DGGE分析 总被引:2,自引:0,他引:2
利用细菌通用引物,对从黄土高原5个地区土壤样品以及西峰剖面26个土壤样品中提取的总DNA进行聚合酶链式反应(PCR)扩增,采用变性梯度凝胶电泳(DGGE)技术对PCR产物进行分析,以揭示黄土高原土壤中细菌群落结构的多样性.针对黄土高原土壤微生物特点进行DGGE试验条件优化,获得最佳变性梯度为40%~70%,最佳电泳时间为17 h(100 V).对不同深度土壤细菌DGGE图谱的聚类分析表明,不同深度土壤细菌呈现2种不同的群落结构,推测其成因可能与季风性气候引起的温湿环境变化及冰期有关.在夏季风加强而冬季风减弱的时期,气候温暖潮湿,风化成壤作用强烈,在DGGE图谱中表现为土壤样品条带多而密;反之,风化成壤作用较弱,在DGGE图谱中表现为条带少而疏.对洛川、西峰等5个地区土壤细菌Shannon-Weiner指数的测定结果表明,Shannon-Weiner指数受条带亮度及迁移率的影响. 相似文献
927.
广东新会银湖湾湿地鸟类群落组成及多样性 总被引:2,自引:0,他引:2
2006年8月至2007年7月,采用系统抽样技术和样带法,对广东省江门市新会区银湖湾湿地鸟类群落进行研究,共记录70种,隶属13目28科48属。新会银湖湾湿地带鸟类平均密度356只/hm2,鸟类物种多样性指数3.690 2、均匀度指数0.875 6、优势度指数0.25。芦苇红树林潮间湿地、鱼塘莲藕湿地和农田果园是新会银湖湾湿地典型的生境,各生境的鸟类种类、密度和多样性差异较大。其中芦苇红树林潮间湿地55种,平均密度338只/hm2;鱼塘莲藕湿地有40种,平均密度279只/hm2;农田果园有38种,平均密度247只/hm2。3种生境中芦苇红树林潮间湿地鸟类的生物多样性最高,农田果园最低。 相似文献
928.
基于模糊聚类法研究绥宁黄桑自然保护区种子植物多样性与邻近地区之间的关系 总被引:9,自引:0,他引:9
杨宁 《湖南环境生物职业技术学院学报》2008,14(3):1-3
通过对绥宁黄桑自然保护区植物多样性与其相邻的其余的9个地区植物多样性进行模糊聚类分析,结果表明,按与其区系关系的密切程度的大小进行排列,与绥宁县黄桑自然保护区的关系的密切从大至小的顺序为:台湾岛〉井冈山〉武夷山〉大罗山〉白云山〉北山〉北仑山〉黄山〉神农架,旨在对植物分类方法的研究作一个有益的尝试,探索一条植物分类的新方法,同时其结果对黄桑自然保护区的经营管理和保护具有一定的实践指导意义.图1,表2,参14. 相似文献
929.
采用厚源法测定地表水、废水中总α放射性,并通过6家实验室间比对验证厚源法的重复性、再现性和准确性。结果表明:方法探测下限不高于0.043 Bq/L。对总α放射性水平为0.046 Bq/L的地表水和25.6 Bq/L的废水样品重复性限为0.021 Bq/L和5.29 Bq/L,再现性限为0.022 Bq/L和8.69 Bq/L,加标回收率最终值为(104±17.6)%和(103±11.6)%。 相似文献
930.
黄浦江是连接太湖与长江口的一条多功能平原感潮河流,流经上海市中心城区,干流长113.4 km。为从生态学角度揭示其污染程度,采用鱼类生物完整性指数(F-IBI)对其水生态系统的健康状况作了评价。2013年11月和2014年7月,采用地笼网、三层刺网和拖网对黄浦江7个断面作了相同努力量的样本采集,共获鱼类8 816尾。经鉴定有38种,隶属于6目12科,其中鲤形目24种,鲈形目7种,鲇形目4种。通过区分度分析和关联度筛选,构建了由9个指标组成的F-IBI评价体系。结果表明,黄浦江上游水生态系统总体上处于"好"状态,中游及河口处于"一般"至"差"之间,而下游则较"差"。春季各有3个江段"好"或"差",1个江段"一般";秋季有4个江段"一般",2个江段"差",仅有1个江段"好"。评价还表明,黄浦江上游的3大支流中,由于承接太湖来水的斜塘呈"差",导致了为上海市提供约30%原水的松浦大桥断面呈"差"或"一般"状态。因此,保护淀山湖乃至太湖水质,是确保黄浦江上游水源地原水安全的关键。 相似文献