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In alpine regions worldwide, climate change is dramatically altering ecosystems and affecting biodiversity in many ways. For streams, receding alpine glaciers and snowfields, paired with altered precipitation regimes, are driving shifts in hydrology, species distributions, basal resources, and threatening the very existence of some habitats and biota. Alpine streams harbour substantial species and genetic diversity due to significant habitat insularity and environmental heterogeneity. Climate change is expected to affect alpine stream biodiversity across many levels of biological resolution from micro‐ to macroscopic organisms and genes to communities. Herein, we describe the current state of alpine stream biology from an organism‐focused perspective. We begin by reviewing seven standard and emerging approaches that combine to form the current state of the discipline. We follow with a call for increased synthesis across existing approaches to improve understanding of how these imperiled ecosystems are responding to rapid environmental change. We then take a forward‐looking viewpoint on how alpine stream biologists can make better use of existing data sets through temporal comparisons, integrate remote sensing and geographic information system (GIS) technologies, and apply genomic tools to refine knowledge of underlying evolutionary processes. We conclude with comments about the future of biodiversity conservation in alpine streams to confront the daunting challenge of mitigating the effects of rapid environmental change in these sentinel ecosystems.  相似文献   
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Habitat destruction is driving biodiversity loss in remaining ecosystems, and ecosystem functioning and services often directly depend on biodiversity. Thus, biodiversity loss is likely creating an ecosystem service debt: a gradual loss of biodiversity‐dependent benefits that people obtain from remaining fragments of natural ecosystems. Here, we develop an approach for quantifying ecosystem service debts, and illustrate its use to estimate how one anthropogenic driver, habitat destruction, could indirectly diminish one ecosystem service, carbon storage, by creating an extinction debt. We estimate that c. 2–21 Pg C could be gradually emitted globally in remaining ecosystem fragments because of plant species loss caused by nearby habitat destruction. The wide range for this estimate reflects substantial uncertainties in how many plant species will be lost, how much species loss will impact ecosystem functioning and whether plant species loss will decrease soil carbon. Our exploratory analysis suggests that biodiversity‐dependent ecosystem service debts can be globally substantial, even when locally small, if they occur diffusely across vast areas of remaining ecosystems. There is substantial value in conserving not only the quantity (area), but also the quality (biodiversity) of natural ecosystems for the sustainable provision of ecosystem services.  相似文献   
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土壤病毒生态学研究方法   总被引:5,自引:1,他引:4  
韩丽丽  于丹婷  贺纪正 《生态学报》2017,37(6):1749-1756
病毒是地球上最丰富的生物实体,每克土壤中可包含数以亿计的病毒,它不仅影响土壤中其它微生物的群落组成、土壤元素的生物地球化学循环,还会影响土壤微生物的物种进化,甚至影响植物、动物和人体健康。目前人们对土壤中病毒的种类及丰度、分布特征以及功能引起的生态环境效应还知之甚少。在概述病毒生态学研究方法的基础上,对土壤病毒的提取、纯化、定量及分子生态学方法等基本流程进行了比较分析,以期建立一套快速简便、高效稳定的适用于土壤病毒研究的方法,并用于研究土壤病毒的多样性及分布特征,探讨病毒在环境中的生存和传播机制,为土壤病毒的防控及开发利用提供支撑。  相似文献   
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Land use changes have profound effects on populations of Neotropical primates, and ongoing climate change is expected to aggravate this scenario. The titi monkeys from eastern Brazil (Callicebus personatus group) have been particularly affected by this process, with four of the five species now allocated to threatened conservation status categories. Here, we estimate the changes in the distribution of these titi monkeys caused by changes in both climate and land use. We also use demographic‐based, functional landscape metrics to assess the magnitude of the change in landscape conditions for the distribution predicted for each species. We built species distribution models (SDMs) based on maximum entropy for current and future conditions (2070), allowing for different global circulation models and contrasting scenarios of glasshouse gas concentrations. We refined the SDMs using a high‐resolution map of habitat remnants. We then calculated habitat availability and connectivity based on home‐range size and the dispersal limitations of the individual, in the context of a predicted loss of 10% of forest cover in the future. The landscape configuration is predicted to be degraded for all species, regardless of the climatic settings. This include reductions in the total cover of forest remnants, patch size and functional connectivity. As the landscape configuration should deteriorate severely in the future for all species, the prevention of further loss of populations will only be achieved through habitat restoration and reconnection to counteract the negative effects for these and several other co‐occurring species.  相似文献   
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Ailanthus altissima (Mill.) Swingle commonly known as tree-of-heaven is an invasive tree species that has spread through much of the USA. Significant mortality of A. altissima by a highly host-specific strain of the fungus, Verticillium nonalfalfae Inderb. (formerly Verticillium albo-atrum Reinke and Bethold), has been recently documented in Pennsylvania. To detect the regional distribution of this biological control agent in the Southeast, a windshield survey was conducted in Virginia, North Carolina and South Carolina to locate V. nonalfalfae-infected A. altissima stands. The survey covered 26,500 km of interstate highways and primary and secondary roads. There were 90 potential sites located throughout the three states. Of those, six were found to be infested with the fungus, all in the mountain regions of Virginia. Inoculation tests suggest no difference in virulence among the six V. nonalfalfae isolates on A. altissima, which resulted in 100% mortality in 9–11 weeks post-inoculation. Tree ratings revealed differences in health among sites, but all sites had an increase in disease incidence from 2011 to 2012 (mean = 4.7 ± 3.8%), suggesting this fungus is dispersing. This survey provides evidence that biological control using this fungus may be possible in Virginia.  相似文献   
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Dispersal of natural enemies is an important part of a biological pest-control programme. In augmentative biological control programmes, studies of dispersal are essential to determine the optimal number of release points per hectare. This study evaluated the kind of infestation that is most suitable for conducting these studies, and the dispersal of Trichogramma galloi in corn on eggs of Diatraea saccharalis. Corn plants with eggs laid directly by D. saccharalis moths showed higher rates of parasitism by T. galloi. The dispersal radii of T. galloi were 11.8 and 12.1 m in V6 (collar of sixth leaf visible) and V8 (collar of eighth leaf visible), respectively, and the dispersal areas were 176 and 187 m2 for the two corn phenological stages. Using these data, we determined that 58 and 54 release points are required per hectare to effect a homogeneous coverage of the release area by parasitoids on the corn phenological stages V6 and V8, respectively.  相似文献   
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