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本文采用变形模型可区分度量的概念进行监测网的优化设计。在算法上采用计算机模拟逐一更新的计算过程。为了克服常规模拟法需要人工干预的缺点,引进了一些规则,利用计算机的判断和推理过程,达到了自动设计的目的。作为示范例子,文中最后还给出了一个模拟监测网的设计结果。 相似文献
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Abdur Rashid Muhammad Ayub Asif Javed Sardar Khan Xubo Gao Chengcheng Li Zahid Ullah Tariq Sardar Juma Muhammad Shahla Nazneen 《地学前缘(英文版)》2021,12(3):101128
This study investigates the values of pH, total dissolved solids (TDS), elevation, oxidative reduction potential (ORP), temperature, and depth, while the concentrations of Br, and potentially harmful metals (PHMs) such as Cr, Ni, Cd, Mn, Cu, Pb, Co, Zn, and Fe in the groundwater samples. Moreover, geographic information system (GIS), XLSTAT, and IBM SPSS Statistics 20 software were used for spatial distribution modeling, principal component analysis (PCA), cluster analysis (CA), and Quantile-Quantile (Q-Q) plotting to determine groundwater pollution sources, similarity index, and normal distribution reference line for the selected parameters. The mean values of pH, TDS, elevation, ORP, temperature, depth, and Br were 7.2, 322 mg/L, 364 m, 188 mV, 29.6 °C, 70 m, 0.20 mg/L, and PHMs like Cr, Ni, Cd, Mn, Cu, Pb, Co, Zn, and Fe were 0.38, 0.26, 0.08, 0.27, 0.36, 0.22, 0.04, 0.43 and 0.86 mg/L, respectively. PHMs including Cr (89%), Cd (43%), Mn (23%), Pb (79%), Co (20%), and Fe (91%) exceeded the guideline values set by the world health organization (WHO). The significant R2 values of PCA for selected parameters were also determined (0.62, 0.67, 0.78, 0.73, 0.60, 0.87, ?0.50, 0.69, 0.70, 0.74, ?0.50, 0.70, 0.67, 0.79, 0.59, and ?0.55, respectively). PCA revealed three geochemical processes such as geogenic, anthropogenic, and reducing conditions. The mineral phases of Cd(OH)2, Fe(OH)3, FeOOH, Mn3O4, Fe2O3, MnOOH, Pb(OH)2, Mn(OH)2, MnO2, and Zn(OH)2 (?3.7, 3.75, 9.7, ?5.8, 8.9, ?3.6, 2.2, ?4.6, ?7.7, ?0.9, and 0.003, respectively) showed super-saturation and under-saturation conditions. Health risk assessment (HRA) values for PHMs were also calculated and the values of hazard quotient (HQ), and hazard indices (HI) for the entire study area were increased in the following order: Cd>Ni>Cu>Pb>Mn>Zn>Cr. Relatively higher HQ and HI values of Ni, Cd, Pb, and Cu were greater than one showing unsuitability of groundwater for domestic, agriculture, and drinking purposes. The long-term ingestion of groundwater could also cause severe health concerns such as kidney, brain dysfunction, liver, stomach problems, and even cancer. 相似文献
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A process framework is described to address socio-economic issues related to coastal zone management, specifically as it applies to the mitigation of impacts due to the establishment of marine protected areas (MPAs). Analysis of the existing social environment in Tanzania, including social capital, vulnerable groups and livelihood components, was undertaken to allow for the identification of critical issues and challenges. The developed process framework is a guidance document for decision-makers to incorporate the interests and needs of affected stakeholders. This safeguard commits to a consultative process with clear channels of communication, established grievance procedures, and monitoring and evaluation activities for affected communities. 相似文献
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Calcification in the marine environment is the basis for the accretion of carbonate in structures such as coral reefs, algal ridges and carbonate sands. Among the organisms responsible for such calcification are the Corallinaceae (Rhodophyta), recognised as major contributors to the process world-wide. Hydrolithon sp. is a coralline alga that often forms rhodoliths in the Western Indian Ocean. In Zanzibar, it is commonly found in shallow lagoons, where it often grows within seagrass beds and/or surrounded by green algae such as Ulva sp. Since seagrasses in Zanzibar have recently been shown to raise the pH of the surrounding seawater during the day, and since calcification rates are sensitive to pH, which changes the saturation state of calcium carbonate, we measured the effects of pH on photosynthetic and calcification rates of this alga. It was found that pH had significant effects on both calcification and photosynthesis. While increased pH enhanced calcification rates both in the light and in the dark at pH >8.6, photosynthetic rates decreased. On the other hand, an increase in dissolved CO2 concentration to 26 μmol kg−1 (by bubbling with air containing 0.9 mbar CO2) caused a decrease in seawater pH which resulted in 20% less calcification after 5 days of exposure, while enhancing photosynthetic rates by 13%. The ecological implications of these findings is that photosynthetically driven changes in water chemistry by surrounding plants can affect calcification rates of coralline algae, as may future ocean acidification resulting from elevated atmospheric CO2. 相似文献
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