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建立我国生态环境标准体系的初步构想 总被引:9,自引:0,他引:9
我国的生态环境标准极其薄弱,建立生态环境标准体系是我国生态环境保护的迫切需要。借鉴我国目前针对污染防治的环境标准体系,提出了我国生态环境标准体系的基本框架,以及生态环境标准制订的原则和重点。 相似文献
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Daily compensation irradiation for net photosynthetic rates (ΣI comp) of Skeletonema costatum (Greville) Cleve, Chaetoceros ceratosporum Ostenfeld, Nitzschia sp., Thalassiosira nordenskiöldii Cleve, and Chroomonas salina (Wislouch) Butcher were measured during 1979 to obtain values for use in ecological models describing compensation and critical depths of marine phytoplankton. Batch cultures of these unicellular algae were exposed to temperatures and photoperiods varying from 6° to 15°C and 8.4 to 16.0 h, conditions typical of surface water in Saanich Inlet, a fjord in Vancouver Island, British Columbia, Canada. Results obtained with S. costatum and T. nordenskiöldii provided estimates of ΣI comp varying between 1.8 and 13 J cm-2 d-1, from which a mean value of 7.0 J cm-2 d-1 was calculated for use in ecological models with neritic phytoplankton. No seasonal variation in compensation irradiation was noted because photosynthetic efficiencies, which increased as division rates increased, were balanced by respiration rates, which increased as temperature increased. Results obtained with Chaetoceros ceratosporum, Nitzschia sp., and Chroomonas salina were difficult to interpret, because respiration rates were stimulated and depressed by light, respectively, for the first two species and the last one. This light effect was greatest when cells grew under conditions of low temperature and short photoperiod. Also, under winter and spring conditions, cells of Nitzschia sp. appeared to fix CO2 in the dark and with low irradiances by mechanisms other than photosynthesis. 相似文献
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Ethan D. Schoolman Jeremy S. Guest Kathleen F. Bush Andrew R. Bell 《Sustainability Science》2012,7(1):67-80
Sustainability research is expected to incorporate concepts, methods, and data from a diverse array of academic disciplines.
We investigate the extent to which sustainability research lives up to this ideal of an interdisciplinary field. Using bibliometric
data, we orient our study around the “tripartite model” of sustainability, which suggests that sustainability research should
draw from the three “pillars” of the environmental, economic, and social sciences. We ask three questions: (i) is sustainability
research truly more interdisciplinary than research generally, (ii) to what extent does research grounded in one pillar draw
on research from the other two, and (iii) if certain disciplines or pillars are more interdisciplinary than others, then what
explains this variation? Our results indicate that sustainability science, while more interdisciplinary than other scientific
fields, falls short of the expectations inherent in the tripartite model. The pillar with the fewest articles published on
sustainability—economics—is also the most integrative, while the pillar with the most articles—environmental sciences—draws
the least from outside disciplines. But interdisciplinarity comes at a cost: sustainability research in economics and the
social sciences is centered around a relatively small number of interdisciplinary journals, which may be becoming less valued
over time. These findings suggest that, if sustainability research is to live up to its interdisciplinary ideals, researchers
must be provided with greater incentives to draw from fields other than their own. 相似文献
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针对目前生态气象监测轨道业务的特点,结合工作的实际需要,运用C和C++语言建立了生态气象监测评估业务平台。在程序设计中,采用了生成中间交换文件的结构组织,能够对各模块的输出结果进行详尽直观的分析,并提供了等值线色斑图与区域填充等多种图形绘制方式。该系统可处理AVHRR和EOS/MODIS卫星遥感资料,对气象观测报文进行解译、数据分类管理和质量控制,统计计算水体密度指数、湿润指数、植被覆盖指数、土地退化指数、灾害指数和生态质量综合评价指标,以图形、图像的形式输出生态气象监测评估产品,实现了卫星遥感与生态气象地面监测数据的有效组织和智能化管理。将系统应用于湖南省生态质量气象评价,业务化运行的结果表明,该系统具有较好的业务实用性。〖HJ1〗〖HJ〗
〖HT5”H〗 相似文献
〖HT5”H〗 相似文献
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