黑河流域水资源压力定量评价

从流域水资源开发利用条件、经济发展与用水以及流域水环境压力3个角度出发选取6个指标构建了水资源综合压力指数,对2000-2010年黑河流域的水资源压力状况进行了定量分析。结果表明,黑河流域近11 a来水资源综合压力指数较高,但总体上呈下降态势,从2000年的0.58逐步降到2010年的0.28。多年来黑河流域的综合治理包括节水型社会建设等措施卓有成效,但地下水位不断下降,生态环境缺水严重,农业用水比重过高等问题仍未缓解。建议今后仍要继续加强节水型社会建设,促进水资源高效利用,压缩农业用水量,以不断减轻流域水资源压力,促进流域水资源可持续利用。     

谈水土保持在黄河流域经济持续发展中的地位和作用

黄河流域内蒙古区间是自治区水土流失最严重的地区之一,通过开展水土保持,使生态环境得到了很大改善,为农林牧副等各业的发展打下了良好的基础,为广大群众脱贫致富达小康提供了根本保证。     

Trans-oceanic characterization of zooplankton community size structure using an optical plankton counter

The Atlantic Meridional Transect (AMT), sampling between 50°N and 50°S, is a trans-oceanic research programme to characterize plankton community structure, productivity and bio-optical properties of the upper ocean in relation to ocean provinces and meso-scale features. As part of a suite of continuous measurements, an optical plankton counter (OPC) has been used on the AMT to characterize the surface distribution of zooplankton based on their abundance and community size structure. Results from the OPC were available in real time, and were subsequently validated against microscope counts of zooplankton sampled concurrently along the AMT. Zooplankton community size structure from two sections of the Transect are presented: from the northern edge of upwelling off West Africa to the UK shelf and between the Falkland Islands and Uruguay, where the Transect traversed a warm core ring. Results showing the zooplankton community size structure together with statistical analysis, using principal component analysis (PCA), are compared with the dynamic oceanographic characteristics along the Transect. The application of the OPC for such basin-scale studies provides a methodology for obtaining data on zooplankton abundance and community structure at the appropriate spatial scales for global-scale modelling of the marine ecosystem.     

Relations between fish abundances, summer temperatures, and forest harvest in a northern Minnesota stream system from 1997 to 2007

Merten EC, Hemstad NA, Eggert SL, Johnson LB, Kolka RK, Newman RM, Vondracek B. Relations between fish abundances, summer temperatures, and forest harvest in a northern Minnesota stream system from 1997 to 2007.
Ecology of Freshwater Fish 2010: 19: 63–73. 2009 John Wiley & Sons A/S
Abstract –  Short-term effects of forest harvest on fish habitat have been well documented, including sediment inputs, leaf litter reductions, and stream warming. However, few studies have considered changes in local climate when examining postlogging changes in fish communities. To address this need, we examined fish abundances between 1997 and 2007 in a basin in a northern hardwood forest. Streams in the basin were subjected to experimental riparian forest harvest in fall 1997. We noted a significant decrease for fish index of biotic integrity and abundance of Salvelinus fontinalis and Phoxinus eos over the study period. However, for P. eos and Culaea inconstans , the temporal patterns in abundances were related more to summer air temperatures than to fine sediment or spring precipitation when examined using multiple regressions. Univariate regressions suggested that summer air temperatures influenced temporal patterns in fish communities more than fine sediment or spring precipitation.     

Freshwater ecosystem vulnerability: Is native climatic niche good enough to predict invasion events?

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