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11.
为探讨采暖季城市森林内外ρ(SO2)动态变化及差异性,基于西山国家森林公园林内空气质量监测站数据,结合北京市环境保护监测中心植物园监测站的实时数据,分析2015年采暖季城市森林内外ρ(SO2)变化和影响因素.结果表明:林内外ρ(SO2)日变化基本呈双峰双谷型,在09:00-11:00和20:00-22:00左右达到高峰;采样期间ρ(SO2)月变化呈不显著"V"型,最高值出现在1月,林内外分别为(25.8±9.2)和(31.7±23.4)μg/m3,最低值出现在11月,林内外分别为(19.0±5.2)和(13.0±11.2)μg/m3.林内ρ(SO2)在1-3月低于林外,11-12月高于林外,林内ρ(SO2)变化较林外平缓;气象条件对采暖季城市森林ρ(SO2)变化有重要影响:降水对ρ(SO2)消减效应明显,大风有驱散SO2的作用,同时受风向影响;ρ(SO2)和温度关系不显著(P=0.05,R < 0.40),但和空气相对湿度线性关系显著(α=0.05,Sig=0.00),林内受气象因素影响低于林外.研究显示,城市森林对气态污染物具有一定的缓冲、抵抗和吸收能力,因此应重视发展城市森林生态系统,充分发挥其生态效益,以提高城市大气环境质量. 相似文献
12.
Carbon footprint of food - approaches from national input-output statistics and a LCA of a food portion 总被引:1,自引:0,他引:1
Yrjö Virtanen Sirpa KurppaMerja Saarinen Juha-Matti KatajajuuriKirsi Usva Ilmo MäenpääJohanna Mäkelä Juha GrönroosAri Nissinen 《Journal of Cleaner Production》2011,19(16):1849-1856
The aim of the study, on which this paper is based, was to provide guidance to consumers to make environmentally responsible choices in their food consumption, to assist food supply chain stakeholders to identify the key areas for environmental improvements, and to provide policy makers with a tool for monitoring the potential impacts on climate change resulting from developments within the food sector. At the macro level, the EIO-LCA model was developed specifically for the Finnish food chain; at the micro level, LCAs were performed on 30 lunch portions. The contribution of the Finnish food chain to climate change was 14%, which comprised 40% CO2 emissions, 25% CH4 emissions, and 34% N2O emissions. The share of impacts from domestic agricultural processes was the highest, at 69%. The impact of a single lunch portion ranged between 0.65 and 3.80 kg of equivalent CO2. According to the EIO-LCA model, the average impact was 7.7 kg CO2 eq/person daily. The consumer phase accounted for between 8 and 47% of the climate change impacts for homemade portions. In ready-to-eat portions industry and retail phases were emphasized, representing 25-38% of climate change impacts. We present an approach to steer the Finnish food sector onto an environmentally sustainable path; practical tools for consumers and farmers will especially need to be developed further. 相似文献
13.
《循环经济发展战略及近期行动计划》指出了要推动各类产业园区实施循环化改造,促进园区绿色低碳循环发展的新要求。兰州新区是国务院批复的全国第五个、西北第一个国家级新区,对兰州新区循环化建设提出相应对策。 相似文献
14.
项目档案管理对于电子政务工程项目的成功实施具有十分重要的意义。通过对电子政务工程项目档案特性的分析,探讨了当前项目档案管理中存在的问题,提出了加强档案管理的措施和建议。并以国家环境信息与统计能力建设项目为例,对项目档案管理流程、手段和要求做了详细论述,为电子政务工程项目档案管理提供了有益的经验借鉴。 相似文献
15.
基于第二次全国土地调查的云南省坝区县、半山半坝县和山区县的划分 总被引:3,自引:0,他引:3
云南是我国西部的典型山区省份,地形坡度<8°的坝区面积仅占土地总面积的6%左右。应用云南省第二次全国土地调查中对各县(市、区)≥1 km2坝子的调查和核定成果,选取坝区耕地面积比例、坝区土地面积比例、≥100 km2坝子数等3 个单项指标,并构建了综合指标--坝区土地综合指数,采用主导指标与综合分析相结合的方法,对全省129 个县(市、区) 进行坝区县、半山半坝县和山区县的划分。结果表明,全省有21 个县属于坝区县,37 个县属于半山半坝县,71 个县属于山区县。这一研究修订了以往云南省仅以坝区耕地面积比例为指标而划分出的坝区县、半山半坝县和山区县方案,为云南省及各地合理地进行产业布局(尤其是农业生产布局)、保护坝区优质耕地资源提供科学依据和基础支撑。 相似文献
16.
在第二次全国污染源普查的基础上,利用污染源普查期间配置的软硬件,开发市级区域环境污染源管理平台,进行污染源数据的年度更新,拓展污染源普查软件应用,实现环境管理及环境执法移动终端的应用。拓展二污普一张图的功能,利用移动客户端机动实时及地定位导航等为环境管理执法和环境突发事件应急处置提供技术支持。 相似文献
17.
随着国民经济的快速发展,我国人民的生活水平和质量也随之而提高,对于生态环境以及居住环境的要求也相应提升。水是万物之源,是保障人们生产生活的基本要素之一,为了有效提升水环境质量,先进的水环境监测技术必不可少。随着科学技术的飞速发展,水环境监测技术也在不断调整和优化,逐渐向信息化方向发展,在生态环境保护工作中发挥着不可替代的作用。本文将详细阐述现阶段我国在水环境监测工作中实施的信息化新技术,希望能为相关研究人员提供参考和借鉴。 相似文献
18.
能源环境管理是各界关注的热点话题,也是科学研究的重要方向.以国家自然科学基金资助能源环境管理领域的科研项目为基础数据信息,本文重点分析了"十三五"期间国家自然科学基金在该领域资助项目的总体特征、研究主题和热点变化,并结合新时代科学基金资助导向提出了可能的发展趋势.主要结论包括:①能源环境管理领域面上、青年、地区等自由探索类项目的立项绝对数和学科占比均呈上升趋势,并更多向青年学者倾斜,资助强度保持稳定;②碳、能源和环境是自由探索项目中出现频率最高的热词,与之相关的研究主题随着政策等调整具有动态变化特征;③能源环境管理领域重点、重大等引导类项目和优青、杰青、创新研究群体等人才类项目不断实现突破,增速明显,学科占比优势突出;④问题导向与本土情景、理论体系和一般规律、学科交叉融合,以及市场和微观主体作用是研究选题确立与项目申请时可能需要重点关注的方向. 相似文献
19.
Trace Element Concentrations and Bioindicator Responses in Tree Swallows from Northwestern Minnesota 总被引:5,自引:0,他引:5
Custer CM Custer TW Warburton D Hoffman DJ Bickham JW Matson CW 《Environmental monitoring and assessment》2006,118(1-3):247-266
Extremely high concentrations of cadmium (3.5 μg/g dry wgt.) and elevated concentrations of chromium (>10 μg/g dry wgt.) and mercury (1.6 μg/g dry wgt.) were reported in waterbird tissues at Agassiz National Wildlife Refuge in northwestern Minnesota in 1994. Tree
swallows (Tachycineta bicolor) were studied during 1998–2001 at three drainages into the Refuge, two pools on the Refuge, and at a nearby reference location
to document whether high levels of contaminants were still present, and if so to quantify the source and severity of the contamination.
Trace elements were measured in tree swallow eggs, livers, and diet. Reproductive success and bioindicator responses were
monitored. In 2000, water was drawn down on Agassiz Pool, one of the main pools on the Refuge. This presented an opportunity
to evaluate the response of trace element concentrations in the diet and tissues of tree swallows after reflooding. High concentrations
of trace elements were not detected in swallow tissues, nor were there differences among locations. Less than 20% of swallow
samples had detectable concentrations of cadmium or chromium. Mercury concentrations were low and averaged <0.25 μg/g dry wgt. in swallow tissues. Trace elements, including mercury, did not increase in tree swallows following the 2000 drawdown
at Agassiz Pool. Hatching success and survival of nestlings to 12 days-of-age for tree swallows on the Refuge were similar
to the national average and consistent with background trace element concentrations. Bioindicator measurements were within
the normal ranges as well. 相似文献
20.
Implications of changing national policies on land use in the Chittagong Hill Tracts of Bangladesh 总被引:2,自引:0,他引:2
Land use in the Chittagong Hill Tracts (CHT) of Bangladesh had undergone changes over the past several centuries. The landscape, which was mostly covered with forest with interspersed shifting cultivation plots until the beginning of the colonial period, has gradually changed into a landscape with a blend of land uses. Overall, the forest area has gradually declined, while the area under shifting cultivation and sedentary agriculture has expanded. The process of the change was multi-directional. National forestry, land use, land taxation, population migration policies, and development activities, such as construction of a hydroelectric dam and roads, played an important role in this process. Shifting cultivation had inflicted little damage on the forest until the beginning of the colonial period. The pace of deforestation accelerated with the nationalization of forests which abolished tribal people's customary use and management rights to the forest, and allowed large-scale commercial logging both legally and illegally. The pace was further intensified by the policy encouraging population migration to CHT and construction of a reservoir on the Karnafuli River. Efforts were made to replace shifting cultivation with more productive types of sedentary agriculture. However, much change could not take place in the absence of secure land rights, supportive trade policies, and the required support services and facilities, including infrastructure. Locationally suitable land use evolved in areas where transportation facilities were available and farmers were granted land title with the necessary extension services and credit facilities. These findings have important policy implications for the promotion of environmentally and economically sound land use in CHT. 相似文献