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101.
102.
103.
Eutrophication conditions and ecological status in typical bays of Lake Taihu in China 总被引:4,自引:0,他引:4
Sampling was conducted at three site groups, group E (in East Taihu Bay), G (in Gonghu Bay) and M (in Meiliang Bay) in Lake
Taihu. TN and TP concentrations among site groups was in the increasing order of E < G < M. TP level at G sites is at the
critical threshold for loss of submersed macrophytes. Mean values of DO and Transparence showed different trend, i.e., E >
G > M. The mean phytoplankton fresh-weight biomass at M sites was 5.81 mg/l, higher than that at E sites (4.96 mg/l) and G
sites (5.18 mg/l). Mean zooplankton fresh-weight biomass was in the decreasing order of M (6.4 mg/l) > G (4.9 mg/l) > E (2.7 mg/l).
However, Rotifera density was in the sequence of E > G > M. Both zooplankton biomass and phytoplankton biomass increased with the rise of TN
and TP concentrations. Relationships between zooplankton biomass and phytoplankton biomass showed that zooplankton played
a limited role in the control of algae in eutrophic lakes. Nutrient availability is much more important than zooplankton grazing
pressure in controlling phytoplankton growth in lakes. For most sites in Lake Taihu, reduction of nutrient loading, as well
as macrophyte conservation, zappears to be especially important in maintaining high water quality and regulating lake biological
structure, but for M sites, it’s urgent to control nutrient inputs rather than to restore macrophyte community. 相似文献
104.
模糊综合评价法在矿区塌陷土地复垦潜力评估中的应用 总被引:6,自引:0,他引:6
为了合理利用土地、提高土地生产率、改善矿区及其周围的生态环境,对矿区塌陷土地复垦潜力进行了研究。阐述了模糊综合评价法的基本原理,并以南票矿区为例,选择了塌陷土地复垦潜力评价的二层树状结构因子,确定了隶属度函数、评价指标权重和评价集,得出了塌陷土地复垦潜力的评价结果。为其他矿区塌陷土地复垦潜力评价提供了理论依据。 相似文献
105.
106.
1引言
防护装备在核、生、化环境下起着防放射性灰尘、防生物细菌和防化学毒剂的作用。防护装备的防护性能检测准确与否。直接影响着防护装备产品的质量乃至使用者的生命安全。防护装备的防护性能受湿度的影响很大,以前,在防护装备的防护性能检测过程中是利用干、湿球温度计来检测测试管路中的湿度。 相似文献
107.
随着经济的发展,人们越来越清醒地认识到,以污染环境和破坏生态来换取一时经济繁荣的危害日益突出。正是这种清醒,推动人类文明进行着一场深刻的反思和变革,把追求人与自然的和谐相处,推上当今社会发展主旋律的位置,它预示着人类进入一个生态文明的新时代。生态文明是协调发展物质文明的保障者,是与时俱进的精神文明的塑造者,是日益完善的政治文明的体现者。因此,建设生态文明既是实现全面建设小康社会奋斗目标的内在需要,又是深入贯彻落实科学发展观的重要内容;建设生态文明,必须强化政策支撑,增加生态文明建设的内生动力;必须强化执法监督,增加生态文明建设的环保执行力;必须强化生态补偿能力,构建最具活力的绿色发展模式。 相似文献
108.
Comparative on Causes and Accumulation of Selenium in the Tree-rings Ambient High-selenium Coal Combustion Area from Yutangba, Hubei, China 总被引:1,自引:0,他引:1
Liu G Zhang Y Qi C Zheng L Chen Y Peng Z 《Environmental monitoring and assessment》2007,133(1-3):99-103
Toxic trace elements emitted during coal combustion are the main sources of air pollution. They are released into the atmosphere
mainly in the forms of fine ash, smoke and flue, and thus adversely affect plant, animal and human health. Selenium is one
of toxic and the most volatile in coal. Large amount of atmospheric emission of selenium, as well as selenium present and
scrubber stockpiles in ash may create serious environmental problems. In the paper, on the basis of investigating the abundance
and distribution of selenium in plant-rings during recent 20 years, the bioaccumulation of selenium is explained that selenium
in plant, which were collected from the village of selenium-rich coal combustion, is much higher than that in plants collected
away from the village of selenium-rich coal combustion. The main origins of selenium are selenium-rich coal combustion and
high-selenium rock weathered. The selenium recycle by food chain and selenium will accumulate and redistribute in environments. 相似文献
109.
110.
Dryland area occupies 37% of the national territory in China. Desertification and other disasters have limited dryland sustainable development. Here we overview the dryland characteristics and desertification status and introduce four regionally optimized eco‐productive paradigms for dryland sustainable development, i.e., the mountain‐oasis paradigm in arid desert; the small watershed‐based paradigm on the Loess Plateau; the integrated animal husbandry paradigm on the Inner Mongolia Steppe and the agro‐pastoral transitional region; and three circle paradigm on the Ordos Plateau. These paradigms are established on the basis of regional landscape patterns and their underlying material and energy flow rules, and different functional belts are determined and capitalized upon with the integrated consideration of regional biogeophysical processes, biogeochemical cycles and biogeosocial relations. These paradigms cannot cover all complex landscape types, but provide theoretical frameworks and practicable models for dryland sustainable development in China. 相似文献