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Environmental Science and Pollution Research - China is the most populous country in the world, and the pollution caused by the excessive population should not be underestimated. In recent years,...  相似文献   
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Land degradation is a global problem that seriously threatens human society. However, in China and elsewhere, ecological restoration still largely relies on a traditional approach that focuses only on ecological factors and ignores socioeconomic factors. To improve the effectiveness of ecological restoration and maximize its economic and ecological benefits, a more efficient approach is needed that provides support for policy development and land management and thereby promotes environmental conservation. We devised a framework for assessing the value of ecosystem services that remain after subtracting costs, such as the opportunity costs, costs of forest protection, and costs for the people who are affected by the program; that is, the net value of ecosystem services (NVES). To understand the difference between the value of a resource and the net value of the ecosystem service it provides, we used data on VES, timber sales, and afforestation costs from China's massive national afforestation programs to calculate the net value of forest ecosystem services in China. Accounting for the abovementioned costs revealed an NVES of ¥6.1 × 1012 for forests in 2014, which was 35.9% less than the value calculated without accounting for costs. As a result, the NVES associated with afforestation was 55.9% less than the NVES of natural forests. In some regions, NVES was negative because of the huge costs of human-made plantations, high evapotranspiration rates (thus, high water opportunity costs), and low forest survival rates. To maximize the ecological benefits of conservation, it is necessary to account for as many costs as possible so that management decisions can be based on NVES, thereby helping managers choose projects that maximize both economic and ecological benefits.  相似文献   
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Fu  Li  Chen  Yi  Yang  Xinyi  Yang  Zuyao  Liu  Sha  Pei  Lei  Feng  Baixiang  Cao  Ganxiang  Liu  Xin  Lin  Hualiang  Li  Xing  Ye  Yufeng  Zhang  Bo  Sun  Jiufeng  Xu  Xiaojun  Liu  Tao  Ma  Wenjun 《Environmental science and pollution research international》2019,26(20):20137-20147
Environmental Science and Pollution Research - Fetal growth has been demonstrated to be an important predictor of perinatal and postnatal health. Although the effects of maternal exposure to air...  相似文献   
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When accounting the CO2 emissions responsibility of the electricity sector at the provincial level in China,it is of great significance to consider the scope of both producers’ and the consumers’ responsibility,since this will promote fairness in defining emission responsibility and enhance cooperation in emission reduction among provinces.This paper proposes a new method for calculating carbon emissions from the power sector at the provincial level based on the shared responsibility principle and taking into account interregional power exchange.This method can not only be used to account the emission responsibility shared by both the electricity production side and the consumption side,but it is also applicable for calculating the corresponding emission responsibility undertaken by those provinces with net electricity outflow and inflow.This method has been used to account for the carbon emissions responsibilities of the power sector at the provincial level in China since 2011.The empirical results indicate that compared with the production-based accounting method,the carbon emissions of major power-generation provinces in China calculated by the shared responsibility accounting method are reduced by at least 10%,but those of other power-consumption provinces are increased by 20% or more.Secondly,based on the principle of shared responsibility accounting,Inner Mongolia has the highest carbon emissions from the power sector while Hainan has the lowest.Thirdly,four provinces,including Inner Mongolia,Shanxi,Hubei and Anhui,have the highest carbon emissions from net electricity outflow- 14 million t in 2011,accounting for 74.42% of total carbon emissions from net electricity outflow in China.Six provinces,including Hebei,Beijing,Guangdong,Liaoning,Shandong,and Jiangsu,have the highest carbon emissions from net electricity inflow- 11 million t in 2011,accounting for 71.44% of total carbon emissions from net electricity inflow in China.Lastly,this paper has estimated the emission factors of electricity consumption at the provincial level,which can avoid repeated calculations when accounting the emission responsibility of power consumption terminals(e.g.construction,automobile manufacturing and other industries).In addition,these emission factors can also be used to account the emission responsibilities of provincial power grids.  相似文献   
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The quantitative relationship between the median effective concentration (EC50) of organic chemicals to Daphnia magna and the number of molecular fragments was investigated based on experimental EC50 values for 217 chemicals derived from the literature. A fragment constant model was developed based on a multivariate linear regression between the number of fragments and the logarithmically transformed reciprocal values of EC50. Functional correction factors were introduced into the model. The model was verified using an independent set of randomly selected data. The mean residual of the final model was 0.4 log-units. The robustness of the model was discussed based on the results of three jackknife tests.  相似文献   
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通过田间定位试验,研究了石灰(L)、钙镁磷肥(G)、泥炭(P)、猪粪(M)、石灰 泥炭(L P)、石灰 猪粪(L M)、钙镁磷肥 泥炭(G P)、钙镁磷肥 猪粪(G M)等改良材料对新罗区特钢厂附近的重金属污染田的长期改良效应.结果表明:大部分处理可提高土壤的pH值、有机质含量,降低了土壤的有效锌含量,石灰 泥炭、钙镁磷肥 泥炭的改良效果要优于单施有机、中性化改良剂和其它处理,和对照相比,有效锌含量和糙米锌含量最高分别降低了59.2%、36.2%.  相似文献   
8.
Fenton法氧化处理水中土霉素的研究   总被引:2,自引:0,他引:2  
为了评价Fenton法预处理抗生素生产废水中残留的高浓度土霉素的可行性,对Fenton试剂(Fe2 -H2O2)法催化氧化降解水溶液中的土霉素进行了研究.探讨了H2O2与Fe2 投加比例、投加量以及起始pH值对降解效果的影响,同时考察了土霉素废水中大量共存的草酸根离子对氧化过程的影响.结果表明,当H2O2与Fe2 按照5:1的比例投加时降解效率最高,最佳初始pH值在3.0-4.0之间.在最佳投加比例下,H2O2投加量为0.9 mmol/L,100 mg/L的土霉素可在10 min内得到完全降解.最佳反应条件下经过处理后土霉素水溶液TOC的去除率达40%左右,可生化性(BOD5/COD)也得到明显的改善.水中共存的草酸根离子对氧化效率具有明显的影响,但通过增加亚铁离子的量可以消除草酸的影响.  相似文献   
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生物絮凝剂MBFGA1预处理乳制品加工废水   总被引:1,自引:1,他引:0  
用生物絮凝剂MBFGA1预处理乳制品加工废水(简称废水)。实验结果表明,废水处理的水力条件为:以150r/min的转速搅拌30S,再以30r/min的转速搅拌20min;MBFGA1的最佳加入量为15mg/L;废水pH为4.0时,MBFGA1对废水的絮凝处理效果最好;废水温度对浊度、COD去除率有一定的影响,在20~45℃时,废水浊度的去除率始终保持在85%以上;30℃时,COD去除率达到最大值65.0%。  相似文献   
10.
利用透射电子显微镜观察分析白腐真菌(黄孢原毛平革菌)在处理染料废水活性艳红X-3B过程中,染料和盐度对黄孢原毛平革菌的细胞结构产生的毒性作用.结果表明:活性艳红X-3B染料对黄孢原毛平革菌产生生物毒性作用,且随着染料浓度的增加,细胞受损伤程度不断加深.加入100 mg/L的染料活性艳红X-3B后,黄孢原毛平革菌菌丝细胞形态发生变化,出现质壁分离现象;染料浓度进一步加大,菌丝细胞超微结构受到损伤逐渐严重.染料废水中的盐度对黄孢原毛平革菌细胞也会造成损伤,且损伤程度随盐度增大而增大.NaCl浓度为3 g/L时,菌丝细胞发生质壁分离;而当NaCl加入量高于8 g/L时,细胞膜受损,线粒体、细胞核呈现空泡化,表现为受到不可逆的损伤.染料和盐双因子对黄孢原毛平革菌细胞的损伤效应表现为其损伤程度与单因子作用一致,且染料的影响作用占主导.  相似文献   
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