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981.
信息时代的到来,传统的档案工作业务环节发生了转变,环境监测档案也不例外。以纸质档案为核心的传统管理模式逐步转变为电子文件的管理模式。本文以四川省环境监测总站环境监测档案为例,分析环境监测档案管理现状、存在的问题并提出环境监测档案规范化管理措施与对策。 相似文献
982.
983.
构建旅游环境承载力评价体系,运用耦合度指数和结构方程模型揭示山东半岛蓝色经济区旅游环境承载系统的耦合演化规律和动态关联特征.研究表明,半岛蓝色经济区7市各子系统的承载指数均呈增长态势,各承载子系统之间存在耦合作用,协调发展水平均稳步上升,生态承载子系统对经济承载子系统产生正影响,社会承载子系统可通过生态承载子系统对经济承载子系统产生正向影响力. 相似文献
984.
SUMMARY This study explores differences among organic farmers who live in islands and have isolated small-size operations. The relationships between farmers' characteristics and attitudes and farm management were interpreted by studying how they manage their land, their attitudes towards the environment and alternative farming systems, and their involvement in organic farming. The research was carried out using questionnaires addressed to organic farmers on the island of Thassos. Nonlinear canonical correlation was applied for data analysis. This information could contribute to adjustment of policy decisions for on-farm diversification. Agricultural policy makers should approach organic farmers in northern Thassos (productive irrigated olive orchards with gentle slopes) by enacting standards to reduce the cost of alternative plant protection methods and promoting their products in order to maintain and expand organic farming. They should also approach organic farmers in southern Thassos (less productive, dry cultivated olive orchards with steep slopes, overgrazed and often abandoned) by providing them with the necessary information and appropriate agricultural know-how to effectively manage their farms. Organic farmers with stable off-farm income are more aware of environmental values and consider that they risk less than others in order to gain the benefits of alternative farming systems. However, they should attend training programmes to achieve economic success to allow them to continue farming organically. 相似文献
985.
Runa Masuma Tsutomu Okuno Mohammad Shahabuddin Kabir Choudhuri Takeshi Saito 《Journal of environmental science and health. Part. B》2013,48(6):416-421
The safety of Tinospora cordifolia and its potential to protect against ultraviolet radiation‐induced cytotoxicity and DNA damage in PC12 cells were investigated. To evaluate the safety of T. cordifolia, cell viability and agarose gel electrophoresis were carried out using PC12 cells treated with 0 to 100 μg mL?1 of methanol extract of T. cordifolia. T. cordifolia extracts did not show cytotoxicity ranging 0 to 100 μg mL?1. In addition, T. cordifolia extracts significantly increased cell viability at 1 ng, 10 ng and 1 μg mL?1 concentrations in serum‐deprived medium compared to control. To confirm the protective role against UV‐induced damage, PC12 cells alone or in the presence of 10 ng, 100 ng, or 1 μg mL?1 of T. cordifolia extract were exposed to 250, 270 and 290 nm of UV radiation, which corresponded to doses of 120, 150 and 300 mJ cm?2, respectively. Treatment with T. cordifolia extracts significantly increased the cell survival rate irradiated at 290 nm. In addition, T. cordifolia extracts significantly reduced cyclobutane pyrimidine dimer formation induced by UV irradiation at all wavelengths. In conclusion, T. cordifolia is not toxic and safe for cells. Our findings can support its application as phototherapy in the medical sector. 相似文献
986.
文中总结宿迁经济开发区环保工作现状,分析未来宿迁经济开发区面临:水环境质量未能根本好转、生活污染物排放量上升并成为主要污染问题、环境基础设施建设滞后于社会经济发展、工业企业污染存在反弹趋势、农村环境问题亟需关注、客水污染问题仍然存在等挑战,并提出了应对这些挑战的对策。 相似文献
987.
ADRIZAL P. H. PATTERSON R. M. HULET R. M. BATES 《Journal of environmental science and health. Part. B》2013,48(6):1001-1018
A chamber study was conducted to evaluate the growth response and leaf nitrogen (N) status of four plant species exposed to continuous ammonia (NH3) for 12 weeks (wk). This was intended to evaluate appropriate plant species that could be used to trap discharged NH3 from the exhaust fans in poultry feeding operations before moving off-site. Two hundred and forty bare-root plants of four species (Juniperus virginiana (red cedar), Gleditsia triacanthos var. inermis (thornless honey locust), Populus sp. (hybrid poplar), and Phalaris arundinacea (reed canary grass) were transplanted into 4- or 8-L polyethylene pots and grown in four environmentally controlled chambers. Plants placed in two of the four chambers received continuous exposure to anhydrous NH3 at 4 to 5 ppm while plants in another two chambers received no NH3. In each of the four chambers, 2 to 4 plants per species received no fertilizer while the rest of the plants were fertilized with a 100 ppm solution containing 21% N, 7% phosphorus, and 7% potassium. The results showed that honey locust was the fastest-growing species. The superior growth of honey locust among all species was also supported by its total biomass, root, and root dry matter (DM) weights. For all species there was a trend for plants exposed to NH3 to have greater leaf DM than their non-exposed counterparts at 6 (43.0 vs. 30.8%; P = 0.09) and 12 wk (47.9 vs. 36.6%; P = 0.07), and significantly greater (P ≤ 0.05) leaf N content at 6 (6.44 vs. 3.67%) and 12 wk (7.05 vs. 3.51%) when exposed to NH3. Numerically greater leaf DM due to NH3 exposure was also consistently measured in poplar at both sampling periods. Hybrid poplar, as well as honey locust and reed canary grass, deposited 1.5 to 2-fold greater N in their leaves than red cedar tissues as a result of NH3 exposure compared to non-exposed plants. Regardless of the effect of NH3 on foliar color and damage score of the plants, the increase of foliar N content (g 100 g?1 of fresh foliage weight) after NH3 exposure at 6 and 12 wk was 0.45 and 0.87 for grass,1.25 and 1.34 for locust, and 2.67 and 6.09 for poplar. However, only honey locust likely benefited from ambient NH3 as indicated by its consistent leaf color quality and lower damage score, compared with other species that were adversely affected by atmospheric NH3. 相似文献
988.
陈雪峰 《中国人口.资源与环境》2011,(Z1)
在综述煤层气对于煤矿安全生产以及环境危害的基础上,从保护环境、缓解能源紧张、延长煤层气的产业链、减少瓦斯危害等多个角度综合分析了煤层气开发所带来的巨大效益,并以黔西北煤矿为例,叙述了煤层气的资源量现状及其地质特征等基本情况。简述了目前我国煤层气的开发现状,并提出了四条增产措施,这些措施必将对推动贵州省经济与环境的可持续发展,加快贵州省工业强省步伐起到积极作用。 相似文献
989.
虽然以往对于环境库兹涅兹曲线(EKC)的研究中考虑了正式制度因素如政府机构监督,但是较少考虑非正式制度因素.本文重点检验两种制度情境的影响,微观层面的环境态度形成的非正式制度以及宏观层面的环保机构监督形成的正式制度对大气污染排放量的影响.基于CGSS2010-2013和2015年的数据库,从中提取出体现环境态度的问题,将其赋值指标化后,作为制度情境纳入环境方程.经过公开数据的收集,得到我国26个省份2010-2014年5年的面板数据.通过固定效应和随机效应模型,发现机构监督与人均GDP的交互项对氮氧化物、烟(粉)尘、二氧化硫排放都有影响,但是公众态度与人均GDP的交互项只对烟(粉)尘排放有影响,从而对不同制度情境下的环境库兹涅兹曲线进行了探索. 相似文献
990.
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