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91.
92.
陈孝麟  林昱 《台湾海峡》1993,12(2):160-163
作者首次应用3个中尺度海洋实验生态系围隔装置研究可溶性Fe 对浮游生物群落数量变动的影响。结果表明:添加10和50μg/dm~3的可溶性Fe,均大大促进了浮游植物,特别是硅藻类中中肋骨条藻(Skeletonema costatum)的生长。但浮游植物的过量繁殖并没有导致生态系中滤食性桡足类数量的增加。  相似文献   
93.
Abstract. Both the emergent surfaces and tide pools of the rocky intertidal shores of the Bay of Morbihan, Kerguelen are depauperate in number of macroinvertebrate and macroalgal species. Diversity (H') was high and similar for macroinvertebrates in tide pools from the high to low intertidal and on the emergent surface exposed at extreme low-tide when calculated in terms of numbers of individuals. H' was lower when calculated in terms of energy and twice as high for the tide pool in the high intertidal than the lower tide-pools and the emergent surface. H' for macroalgae was 0 in the highest tide-pool and highest in the lower tide-pools. The density/species-rank curves for the macroinvertebrates and the macroalgae are logarithmic but vary in linearity. Algal biomass was 37 % of the macroinvertebrate biomass on the emergent surface at the extreme low-tide, but 106% in the highest tide-pool. Twenty-three months after denudation of the tide pools, the ratios of total densities of the macroinvertebrates (ind m-2) to the original densities were 48 % for the pool in the high intertidal, 25 % for the middle tide-pool, and 4 % for the pool in the low intertidal. The diversity indexes for the macroinvertebrates were similar to the original ones. Recolonization at Kerguelen is slow and shows an intertidal gradient. The composition of the rocky intertidal community at Kerguelen results from the rigorous physical environment and the small number and functional types of species. In the absence of major predators on macroinvertebrates and of herbivores on macroalgae, interaction among the species present seems to be competitive in nature.  相似文献   
94.
95.
Surficial sediment samples, collected from the continental margin of the southwest coast of India in July 2004, were examined for the grain size and soft-bottom macrobenthic fauna, to understand the sediment granulometry and its effect on the faunal distribution. Samples were collected using Smith-McIntyre Grab, from 20 to 200 m depth range, consisting of mid-shelf, outer shelf and slope. Fine-grained sediment located in the mid shelf and supported low faunal abundance. Polychaetes constituted the bulk of the fauna. Feeding guild changed with depth and sediment granulometry. Coexistence of deposit feeders and carnivores in outer shelf and deposit feeders and filter feeders in the slope region indicated the effective utilization of different food resources. In general, richness and diversity were high in the southern region. Depth wise, the diversity and abundance were relatively high in the 50–75 m depth range. Correlation and BIO-ENV analysis showed that combination of different factors such as sediment texture, sediment sorting and depth were found to influence the distribution of macrobenthos. Hence, spatial variations observed in benthic community were presumably linked to the variations in sediment granulometry and the energy level conditions prevailing in the area.  相似文献   
96.
The use of AMBI and M-AMBI in benthic quality assessments, within the European Water Framework Directive (WFD), has increased dramatically in recent years. M-AMBI is a multivariate tool, which incorporates AMBI, richness and Shannon diversity within the assessment. The response of this approach to different human pressures in coastal and estuarine waters has been investigated for the Basque Country (Northern Spain). In this contribution, several paradigmatic examples of these applications to different water bodies are presented. The time-series extend to samples collected between 1995 and 2007, showing the evolution of M-AMBI values under different pressures, i.e. urban and industrial discharges, dredging and disposal of sediments, and engineering works (such as land reclamation or marina construction), and, in addition, for illustrating the benthic quality recovery after positive actions have been undertaken, i.e. the removal of point-source discharges or water treatment programmes. In most cases, M-AMBI responds to these pressures as expected, with decreases in the ecological status immediately following the pressure. Conversely, when a pressure is removed, the recovery takes between 2 and 15 years, depending upon the intensity of the pressure and the characteristics of the water body. M-AMBI has been intercalibrated previously in coastal waters. After intercalibration in transitional waters, M-AMBI will be able to be used in the integrative quality assessment of European water bodies.  相似文献   
97.
The push for catch shares is on in the United States, nationwide generally, and in the western Pacific specifically. The prevailing understanding of catch shares emphasizes individual private property rights and changes in fisher behavior are understood to result from changes in rights in accordance with a long-established canon in fisheries economics. It is argued that this orthodoxy misses the causal factor in catch shares and thus constricts the range of policy options for catch shares. Moreover, this standard understanding of catch shares fosters opposition. Opposition to catch shares in the western Pacific can be understood as a specific variant of a generic pattern of opposition that is often centered on concerns for distributional impacts. Blind to the fact that their own misunderstanding fuels opposition, proponents of privatization resort to explaining opposition in terms of a simple, but inaccurate, for-or-against-catch-shares dichotomy. Perpetuation of this dichotomy has become a tool in the promotion of one particular ideological conception of catch shares and is a disservice to the public policy process. A possible path forward in the context of the western Pacific is presented that is based on diminishing the role of outside policy experts while encouraging local design of programs to meet local goals. Such an approach is consistent with the nature of development as local people adopt and adapt outside influences on their own terms.  相似文献   
98.
In 2010, a tsunami generated by a magnitude 8.8 earthquake struck the central-south zone of Chile. This short communication reports the direct impacts on the small-scale artisanal fishing capacity and coastal livelihoods along approximately 600 km of the coastline. Despite the magnitude of the catastrophe, the absence of official warnings, and the failure of telecommunication networks only 8 fisher victims were reported out of a total death toll of more than 170. Results show that this trend is explained by socio-cultural assets and a natural hazard subculture. This highlights the need to integrate contextual and behavioural approaches in disaster management and rehabilitation policies.  相似文献   
99.
应用Terra和Aqua卫星的MODIS资料和三维叶分布模式,结合MODIS陆地植被覆盖产品数据,估算了6种生物群落的LAI,并与我国西北地区叶面积仪观测结果进行了对比和分析。结果表明,从两颗卫星连续8天的观测资料可以估算出LAI,反演结果的相对误差基本在±20%以内,平均相对误差为13.7%,说明该方法可以反演实际植被的LAI;根据植被类型的差异,建立了6种生物群落LAI与NDVI的指数关系,相关性较好;青藏高原东部的LAI时间变化有不一致性的特征,反映了不同生物群落的生物学特性的差异;不同季节的LAI变化在空间上有很大差异,说明本研究区域西部冷、干和高原东部相对暖、湿的复杂气候特征。  相似文献   
100.
平阴县孝直镇属偏远的农业大镇,为解决村庄规模偏小、布局分散和"空心村"等问题,充分利用国家城乡建设用地增减挂钩政策,以土地综合整治为平台,积极推进大村制建设,合村并点建设新型社区,从根本上改变农村面貌,加速城镇化和城乡一体化进程。  相似文献   
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