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991.
安徽宿州地区石灰岩土壤地球化学特征 总被引:3,自引:1,他引:2
为分析宿州地区石灰岩土壤元素地球化学特征,采集了石灰岩土壤样品,进行主、微量元素测试,利用SPSS软件对测试结果进行相关性及主成分分析,并采用富集因子和地累积指数方法对重金属污染程度进行了评价。结果表明:宿州地区石灰岩土壤主要由Si和Ca构成,元素Ca和Th富集明显,Al亏损严重,其他元素基本与背景值相当;重金属元素Pb、Zn、Cr符合国家一级土壤标准,Cu和As在国家一级土壤和二级土壤之间,重金属污染程度为Cu>As>Cr>Zn>Pb>V;元素Ca与V、Zr主要受控于PC1,指示了陆源碎屑的混染;Pb、Sr和As主要受控于PC2,主要受石灰岩风化的影响;PC3包括Zn、Cu、Al,反映了人类农业活动的影响;结合区域背景推断Cu、Zn主要受人类农业活动(肥料)的影响,As可能和皮革、纺织品等人类活动有关。 相似文献
992.
993.
文章简要介绍了袋式除尘器和旋风除尘器的产生背景和发展历史,说明了两种除尘器的一般结构和工作原理。重点介绍了袋式除尘器和旋风除尘器的性能及其影响因素,并对两者在实际中的应用做了比较,比较结果显示:旋风除尘器主要优点表现在受含尘气体的浓度、温度限制小,对于粉尘的物理性质无特殊要求;压力损失中等,动力消耗不大,运转、维护费用较低;袋式除尘器的主要优点是除尘效率高,特别是对微细粉尘的处理能达到较为理想的效果。由此分析预测了两种除尘器在中国的应用及其发展趋势。 相似文献
994.
Western China has lagged a lot in terms of industrial structure and economic development, compared with the national average. And China announced its target of CO2 emission reduction, i.e. by 2020, CO2 emission per GDP will drop by 40–45% compared with 2005. The target will be incorporated into China’s long-term industrial planning. Against this background, this paper will make a comprehensive examination of the industrial development of Western China, aiming to discover a green and compatible way. First, we analyze the spatiotemporal evolution of regional industrial structure for the period 2000–2010. Second, we try to discover the industrial structure optimization path for Western China by employing the Vector Auto Regression model. Lastly, we try to provide some advice and suggestions for further industrial development in Western China. Our examination shows that further industrial development in Western China should pay full attention to resource conservation and recycling, and develop on a green and compatible path. 相似文献
995.
Understanding changes in soil fertility and soil environmental risks in protected agriculture with high irrigation and fertilizer inputs are of great significance for ecological protection. In this study, soil samples in the plow layer were collected from greenhouses >100 acres in the eastern Qinghai-Tibet Plateau after different durations of planting time (either ≤ 3, 3-5, 5-10, or 10-20 years) to assess the changing pattern of soil fertility indicators and the potential leaching risk of nitrogen and phosphorus. The results showed that soil organic matter (OM) and total nitrogen (TN) contents in protected agriculture were 17.1 and 1.3 g/kg, respectively, which suggests moderate content levels. Meanwhile, soil alkali-hydrolyzed nitrogen (AN), available phosphorus (Olsen-P), and available potassium (AK) contents were 160.9, 72.0, and 191.2 mg/kg, respectively, which suggests abundant content levels. As the number of planting years increased, the contents of soil OM, TN, AN, and Olsen-P increased significantly, especially after 10 years, with 41.6%, 44.2%, 26.5%, and 67.4% increases, respectively, compared to ≤ 3 years. As seen, Olsen-P had the most marked increase. In contrast, soil AK and pH decreased with planting years, and soil AK after 5 years decreased by 32% compared to ≤ 3 years. Moreover, the soil pH value in 3-5 years decreased by 2.3% compared to that of ≤ 3 years. The leaching risk of soil nitrogen and phosphorus was intensified after 10-20 years, and the probability of leaching was 0.74 and 0.84, respectively. This study indicated that, in protected agriculture, soil OM, AN, and Olsen-P contents improved, accompanied by a high risk of N and P loss, and AK and soil pH values decreased. It is recommended that the input of nitrogen and phosphorus fertilizers should be controlled, and the input of potassium fertilizer should be increased for more than 10 years of facility cultivation. This study provides a scientific basis for the rational fertilization of agricultural facilities. The findings indicate that after facility planting for 10-20 years, soil organic matter, nitrogen, and phosphorus significantly increased, yet the leaching risk of nitrogen and phosphorus increased as well, suggesting that the input of nitrogen and phosphorus fertilizer should be controlled. After 3-5 years of planting, soil AK and pH values decreased significantly, implicating that potassium and organic fertilizer should be supplemented in a timely manner. © 2022 Science Press. All rights reserved. 相似文献
996.
Song Lizhong Gao Kui Liu Quanmin Zhang Liangtao Feng Qingsong Guo Wenjie 《Environmental science and pollution research international》2022,29(41):62330-62346
Environmental Science and Pollution Research - With the large-scale construction of suburban railway viaducts, the noise problem along the viaducts is becoming more and more prominent. Conventional... 相似文献
997.
Song Junxiu Geng Linling Fahad Shah 《Environmental science and pollution research international》2022,29(35):52984-52994
Environmental Science and Pollution Research - Poverty is a significant global ongoing issue that influences a substantial amount of people despite all efforts to eliminate or lessen it. Although... 相似文献
998.
Akbulut Özen Songül Yesilkanat Cafer Mert Özen Murat Başsarı Asiye Taşkın Halim 《Environmental science and pollution research international》2022,29(48):72683-72698
Environmental Science and Pollution Research - In this study, the performance of the Sequential Gaussian Simulation (SGS) approach was studied with the aim of accurately determining local health... 相似文献
999.
Zhang Hongbo Wang Hao Li Yingyong Yuan Xuefeng Sun Jie Song Xiuguang Zhao Zhizhong Wu Jianqing 《Environmental science and pollution research international》2022,29(24):35599-35614
Environmental Science and Pollution Research - The recycling of scrap tires has become an important issue in the area of environmental protection in the past 20 years. In recent years, tire strips... 相似文献
1000.
Xiaoman Liu Chang Tian Yanxia Zhao Weiying Xu Dehua Dong Kaimin Shih Tao Yan Wen Song 《Frontiers of Environmental Science & Engineering》2022,16(8):110