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901.
火电行业是我国经济社会发展的重要基础和保障,但也是碳排放的主要源头之一。在“双碳”目标约束下,新能源装机将持续增长,而火电机组则面临降碳和退役的压力。以安徽省为研究区域,考虑“双碳”目标与污染导致的健康损失等因素,对全省现役火电机组的计划退役与有序退役方案进行对比分析,为火电行业实现低碳发展提供路径参考。在有序退役方案下,结合初始投资、使用年限、年度发电收益与污染物排放计算出现役机组每年的净现值,并且根据未来安徽省碳排放削减目标,得到优化后的机组退役时间和顺序。结果表明:与常规的计划退役方案相比,有序退役方案使安徽省火电机组退役时间平均提前约5 a,在2060年碳中和之前可实现现役机组全部退役。2020—2060年,现役机组有序退役可累计减少碳排放量12.76亿t;累计减少SO2、NOx、PM2.5排放量分别为1.44万t、2.13万t、0.17万t,比计划退役方案减少8.66亿元的健康损失。机组的有序退役不仅能带来巨大的环境效益与社会效益,也为“双碳”目标的实现提供了有力保障。  相似文献   
902.
903.
Marine spatial planning provides a comprehensive framework for managing multiple uses of the marine environment and has the potential to minimize environmental impacts and reduce conflicts among users. Spatially explicit assessments of the risks to key marine species from human activities are a requirement of marine spatial planning. We assessed the risk of ships striking humpback (Megaptera novaeangliae), blue (Balaenoptera musculus), and fin (Balaenoptera physalus) whales in alternative shipping routes derived from patterns of shipping traffic off Southern California (U.S.A.). Specifically, we developed whale‐habitat models and assumed ship‐strike risk for the alternative shipping routes was proportional to the number of whales predicted by the models to occur within each route. This definition of risk assumes all ships travel within a single route. We also calculated risk assuming ships travel via multiple routes. We estimated the potential for conflict between shipping and other uses (military training and fishing) due to overlap with the routes. We also estimated the overlap between shipping routes and protected areas. The route with the lowest risk for humpback whales had the highest risk for fin whales and vice versa. Risk to both species may be ameliorated by creating a new route south of the northern Channel Islands and spreading traffic between this new route and the existing route in the Santa Barbara Channel. Creating a longer route may reduce the overlap between shipping and other uses by concentrating shipping traffic. Blue whales are distributed more evenly across our study area than humpback and fin whales; thus, risk could not be ameliorated by concentrating shipping traffic in any of the routes we considered. Reducing ship‐strike risk for blue whales may be necessary because our estimate of the potential number of strikes suggests that they are likely to exceed allowable levels of anthropogenic impacts established under U.S. laws. Evaluación del Riesgo de Colisiones de Barcos y Ballenas en la Planificación Marina Espacial  相似文献   
904.
Heavy metal distribution in medicinal plants is gaining importance not only as an alternative medicine, but also for possible concern due to effects of metal toxicity. The present study has been focused on emphasizing the heavy metal status and bioaccumulation factors of V, Mn, Fe, Co, Cu, Zn, Se (essential metals) and Cr, Ni, Cd, As and Pb (potentially toxic metals) in medicinal plants grown under two different environmental conditions e.g., near to Khetri copper mine and those in fertile soils of Haridwar, both in India, using Instrumental Neutron Activation Analysis (relative method) and Atomic Absorption Spectrometry. The copper levels in the medicinal plants from Khetri were found to be 3-4 folds higher (31.6–76.5 mg kg?1) than those from Haridwar samples (7.40–15.3 mg kg?1), which is correlated with very high copper levels (763 mg kg?1) in Khetri soil. Among various heavy metals, Cr (2.60–5.92 mg kg?1), Cd (1.47–2.97 mg kg?1) and Pb (3.97–6.63 mg kg?1) are also higher in concentration in the medicinal plants from Khetri. The essential metals like Mn (36.4–69.3 mg kg?1), Fe (192–601 mg kg?1), Zn (24.9–49.9 mg kg?1) and Se (0.13–0.91 mg kg?1) and potentially toxic metals like Ni (3.09–9.01 mg kg?1) and As (0.41–2.09 mg kg?1) did not show much variations in concentration in the medicinal plants from both Khetri and Haridwar. The medicinal plants from Khetri, e.g., Ocimum sanctum, Cassia fistula, Withania somnifera and Azadirachta Indica were found rich in Ca and Mg contents while Aloe barbadensis showed moderately high Ca and Mg. Higher levels of Ca-Mg were found to correlate with Zn (except Azadirachta Indica). The bioaccumulation factors (BAFS) of the heavy metals were estimated to understand the soil-to-plant transfer pattern of the heavy metals. Significantly lower BAF values of Cu and Cr were found in the medicinal plants from Khetri, indicating majority fraction of these metals are precipitated and were immobilized species unsuitable for plant uptake. Overall, Withania somnifera (Ashwagandha) showed very high metal bioaccumulation.  相似文献   
905.
武宁县森林扰动及驱动因子分析   总被引:2,自引:0,他引:2  
森林扰动是影响陆地生态系统的重要因子,也是影响全球碳循环的重要因素.以江西省武宁县为例,利用1986-2011年14景Landsat TM/ETM+遥感影像,通过扰动指数(disturbance index,DI)时间序列轨迹分析提取森林扰动信息,并引入经验正交函数(empirical orthogonal function,EOF)分解方法定量分析了森林扰动的时空变化规律,利用GIS深入分析了自然和社会驱动因子影响.结果表明,武宁县森林扰动在1986-1998年较强,扰动面积以1992年为最大,以地区性扰动为主;2000年以后则趋于平缓,扰动以砍伐和森林火灾为主;在空间上,扰动主要发生在近道路、低海拔、低坡度和近水地区,并受地形和交通的制约,城镇化逐渐成为该地区森林扰动的一个不可忽略的驱动因子.  相似文献   
906.
乙醇对含水层中燃油芳香烃内在生物修复的潜在风险   总被引:1,自引:0,他引:1  
内在生物修复,是在没有工程措施促进的情况下利用土著微生物降解含水层内灾害性物质的一种修复技术,在燃油烃污染管理方面具有显著的成本效益。该技术需要确定自然衰减过程,并能够继续提供有效的风险保护。针对燃油污染含水层,北美与欧洲认为内在生物修复是值得优先考虑的应用技术。然而,随着乙醇燃油的推广使用,我国在应用这样的经验时需要考虑乙醇的潜在影响。现有的文献研究表明乙醇存在能够阻止燃油主要污染物芳香烃(BTEX)的生物降解,降低水环境的pH值,并可能增强BTEX在水中的溶解性,或存在对生物的毒性,或因为乙醇降解降低介质的渗透性能。因此,需要更好地认识乙醇的潜在风险,为发展乙醇燃油污染含水层修复策略提供科学依据。  相似文献   
907.
构建农民工的社会保障体系   总被引:38,自引:0,他引:38  
农民工对城市和农村的发展功不可没。但是,由于制度不健全,遭遇市场风险的农民工缺乏基本的社会保障,处境艰难。本文分析了农民工缺乏社会保障的历史和现实原因,提出了构建农民工社会保障体系的设想,即以健康保障、失业保障和养老保障为主体的过渡性农民工社会保障体系,来衔接城乡社会保障。以适应城乡一体化的需要。  相似文献   
908.
张家口地区生态可持续性评价研究   总被引:4,自引:0,他引:4  
张家口市生态环境比较脆弱。经济上属于河北省落后地区,且近邻首都北京,因此它的发展不断引起人们的关注。本文选用了由加拿大生态学家Rees和Wackenagel等提出的生态足迹模型,对张家口地区进行可持续发展的定量测算。结果表明:张家口市自1990年到2000年一直处于不可持续状态,且人均生态赤字呈逐年增大的趋势。针对这种情况,本文提出全面发展精细农业、促进工业升级以及以“人”为本的区域发展对策。  相似文献   
909.
A growing body of literature has documented the rapidly increasing income disparities that accompanied China's economic growth in the 1980s and 1990s, and the driving factors behind this. Growing income inequality in its turn may have important implications for the accumulation of physical capital, human capital, and natural capital and as a consequence for sustainable economic development. The purpose of this paper is to investigate the potential impact of income inequality on savings, human resources and the environment in China. It starts with an overview of the different causal mechanisms through which income inequality may affect the accumulation of physical capital, human capital, and natural capital, and discusses to what extent these causal relationships may be relevant in the case of China. Next, provincial data for the year 2002 are used to explore the relationship between income inequality and different elements of sustainable development in China. It is found that income inequality does not affect aggregate savings levels. Rising inequality, however, contributes to lower health and possibly also to higher fertility levels. It also lowers the use of chemical fertilizers in agriculture and therefore is likely to reduce water pollution. Other types of environmental degradation are not affected.  相似文献   
910.
目前企业化经营已被越来越多地运用于农业开发的生产管理中。本文阐述了农业开发中企业化经营形式及其重要性,分析了当前企业化经营优势尚未充分发挥的原因,提出了加强农业开发企业化管理的对策。  相似文献   
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