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1.
MFAM模型在河流水质污染模拟及预测中的应用 总被引:2,自引:0,他引:2
文中以时间序列分析为基础,介绍了均值生成函数这一崭新概念,并且经成份因子提取分析推导建立了模拟序列的数字模型(简记为MFAM),经对黄河下游花园口断面的1988-1989年实测水质污染指标溶解氧(DO),氨氧,化学耗氧量(COD),五日生化需氧量(BOD5)等序列模拟,结果表明MFAM模型能较好地模拟河流水质污染指标的变化趋势,拟合平均误差只有5.2-6.4%,MFAM模型应用于预测1990-1991年水质污染指标变化,结果表明预测精度达85%以上,文中最后得出结论:MFAM模型应用于河流污染模拟和预测,是完全可行且十分方便。 相似文献
2.
Ecological risk assessment provides a methodology for evaluating the threats to ecosystem function associated with environmental
perturbations or stressors. This report documents the development of a conceptual model for assessing the ecological risk
to the water quality function (WQF) of bottomland hardwood riparian ecosystems (BHRE) in the Tifton-Vidalia upland (TVU) ecoregion
of Georgia. Previus research has demonstrated that mature BHRE are essential to maintaining water quality in this portion
of the coastal plain. The WQF of these ecosystems is considered an assessment endpoit—an ecosystem function or set of functions
that society chooses to value as evidenced by laws, regulations, or common usage. Stressors operate on ecosystems at risk
through an exposure scenario to produce ecological effects that are linked to loss of the desired function or assessment end
point. The WQF of BHRE is at risk because of the ecological and environmental quality effects of a suite of chemical, physical,
and biological stressors. The stressors are related to nonpoint source pollution from adjacent land uses, especially agriculture;
the conversion of BHRE to other land uses; and the encroachment of domestic animals into BHRE. Potential chemical, physical,
and biological stressors to BHRE are identified, and the methodology for evaluating appropriate exposure scenarios is discussed.
Field-scale and watershed-scale measurement end points of most use in assessing the effects of stressors on the WQF are identified
and discussed. The product of this study is a conceptual model of how risks to the WQF of BHRE are produced and how the risk
and associated uncertainties can be quantified. 相似文献