首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
The abundance of moles has been studied in 2007–2010 along the gradient of pollution by emissions from the Middle Ural (Middle Urals) and Karabash (Southern Urals) Copper Smelters. It has been estimated by the routing method with regard to the number of inhabited burrows per 1 km. Not a single mole has been recorded in heavily polluted areas near these copper smelters. Under conditions of moderate pollution, the abundance of moles decreased 1.5–1.8 times. The smallest “mole desert” near the source of emissions extends for 90–100 km2. A dramatic decrease in the abundance of earthworms, which are the main food object of moles, is considered a possible reason for these changes.  相似文献   

2.
基于我国现有的环境数据条件,将复杂的分布式水文、泥沙模拟(采用SWAT模型)与简化的输出系数方法进行有效整合,建立了可实际应用的流域重金属面源污染负荷模型。应用所建模型对湘江株洲段所属汇水区域的镉面源污染进行动态模拟,并进行不确定性分析。模拟结果显示,研究区镉面源污染负荷总量约为2 435kg/a,受污染土壤对于镉面源负荷量贡献率达657%。土壤侵蚀过程对研究区的面源污染过程起控制作用,因此,土壤污染防治和水土保持是该区域镉面源污染管理的关键。土壤污染程度高且易侵蚀的地区(如清水塘工业区及其邻近地区)是防治的重点区域,而每年的4月和5月是防治的重点时期。不确定性分析结果显示,超过50%的概率下,研究区镉面源负荷总量处于2 000~3 000 kg/a这一范围,但仍有可能低于1 500 kg/a或高于4 000 kg/a  相似文献   

3.
苏南人口密集地区城镇化过程中的环境特征分析   总被引:8,自引:0,他引:8  
江苏省南部是长江三角洲地区的城镇密集区,该地区在工业化带动下的乡村城镇化迅速发展,非农业人口比重大,隐性城市化人口多。城镇化过程中存在以下环境问题:耕地资源减少,环境承载力降低;水污染严重,环境容量减少;工业污染物集中,小城镇排放的污染物浓度大;城镇化后生态风险增大。近期苏南乡村城镇化正处于高峰期,针对城镇化过程中的环境变化特点,应制定符合生态经济规律的小城镇规划,加强土地管理和环境管理,加快乡村城镇化进程,加快乡镇合并,实施乡镇工业经济增长方式的转变。  相似文献   

4.
Microscale Spatial Variation in Forest Litter Phytotoxicity   总被引:1,自引:0,他引:1  
The spatial variation (within a 100 × 100 m plot) in the pollution of forest litter with heavy metals (Cu, Cd, Pb, and Zn), its acidity, and phytotoxicity (measured by the results of the root test using seedlings from a genetically homogeneous sample of common dandelion (Taraxacum officinale s.l.) have been estimated. Forest litter has been sampled in three zones differing in the toxic impact of long-term polymetal pollution by emissions from a copper-smelting plant emissions in the Middle Urals. The phytotoxicity variation is maximum in a moderately polluted plot, where both very high and very low pollution levels were observed, which determines a substantially nonlinear dose–effect relationship. The litter phytotoxicity is mainly accounted for by exchangeable forms of metals. Biological testing of samples from the most polluted plot has demonstrated marked antagonism between heavy metals and acidity.  相似文献   

5.
两种土地利用方式下土壤重金属污染特征与评价   总被引:1,自引:0,他引:1  
为研究安徽铜陵某矿区耕地和人工林地两种土地利用方式下土壤重金属污染特征,应用Tomlinson污染负荷指数法和生物富集系数评价研究区土壤重金属Cd、Cu污染水平和植物重金属富集水平。结果表明:研究区耕地土壤Cd、Cu全量2.34和161.25 mg/kg,均高于林地Cd、Cu全量1.26和80.15 mg/kg,二者均超农用地土壤污染风险筛选值(GB 15618-2018,pH≤5.5)和铜陵市重金属背景值,耕地和林地污染水平分别为中度污染和轻微污染。耕地糙米Cd(0.95 mg/kg)超标严重,黄山栾树地上部Cd、Cu富集系数均低于水稻地上部。综上,黄山栾树人工林地Cd、Cu污染轻于耕地,退耕还林是研究区更佳的土地利用选择。  相似文献   

6.
长江中游地区贫困村空间分异研究   总被引:1,自引:0,他引:1  
以长江中游地区的湖北省、湖南省以及江西省在十三五规划当中所涉及的贫困村为研究对象,采用核密度分析、最近邻指数以及空间自相关等空间统计法,对贫困村的数量、空间分布密度及模式、垂直梯度分异等特征进行了分析。结果表明:(1)长江中游地区贫困村省际分布有所不同。数量上湖南省>湖北省>江西省,并且同时存在典型的“平原型”贫困村和“山区型”贫困村,且在省域、国贫县、省贫县、非贫县、城市圈等多级尺度下的数量特征不同;(2)在城市群或者城市圈内,贫困村分布呈现低值集聚,而省域交界处的山区多为贫困村分布的高值集聚区;在巫山、雪峰山和武陵山的贫困连片分布区,贫困村多呈均匀型分布;在江汉平原地区,出现显著的集聚型分布;(3)贫困村的垂直空间分异显著。贫困村主要分布在海拔<200 m的平原地区,随着海拔的升高,数量不断减少。研究有利于更好地认知和理解长江中游地区的贫困村空间格局,实施更为科学的“精准扶贫”战略。  相似文献   

7.
Abstract

Nowa days, ecological and cultural tourism, especially those ancient villages and towns in China, have attracted an increasing number of tourists because of their unique cultural features. However, rapid development of tourism brings economic benefits, but results in a series of problems that threaten further tourism development and protection of ancient towns, such as over-commercialization and tourism urbanization. Taking Longmen ancient town as an example, this paper presented a sustainable way of preserving and developing resources of ancient villages and towns. First, identify cultural features and the extent of ancient villages and towns, and find the approach through which a cultural landscape zoning can be applied. Second, define a cooperative function area to release the pressure on core areas and protect their authentic cultures by extending tourism space. Third, balance tourism development with traditional industries to enhance the sustainability of community economies.  相似文献   

8.
水资源条件约束下西北农村地区生态经济发展对策   总被引:2,自引:0,他引:2  
西北地区生态脆弱,社会经济发展相对落后。农业在全区经济中占有重要的地位,所以农村地区可持续发展对于实现西北地区可持续发展具有重要意义。通过分析西北地区水资源现状及特点和本区农村社会、经济发展现状,认为西北地区水资源严重缺乏,干旱化趋势将长期存在;农业结构不合理,乡镇工业污染严重、城镇化进程缓慢是制约本区农村地区可持续发展的主要因素。在此基础上,提出了在水资源严重缺乏条件下西北农村地区实现生态经济可持续发展的具体对策:积极调整农业结构,大力发展节水农业和推进农业产业化;加强小城镇社区生态环境基础设施建设,实施城镇化发展战略和乡镇企业可持续发展;建设生态型的小城镇,建立农村地区新型生态能源结构,加强小流域综合治理是改善农村生态环境和实现农村地区生态经济可持续发展的有效途径。  相似文献   

9.
The aim of research was to assess the changes of annual radial increment of Scots pine forests in the vicinity of intensive and moderate industrial pollution of “Achema” factory producing mineral fertilizers. Our results indicate that the radial growth of the pine tree can be divided into three different periods: growth promotion, growth inhibition and growth recovery. Low levels of nitrogen emissions were beneficial for tree growth: the radial increment in the intensive and moderate pollution zones increased by 15–25% and 10%, respectively compared to control. During the growth inhibition period, the total annual industrial emission was 37–40 kt, and 40–45% radial growth loss was observed for the closest and 15–20% for the most distant stands. The radial growth decrease slowed down and the recovery of damaged stands began in 1990–1992 then air pollution was considerably reduced. The rate of forest recovery was high for the most damaged stands: their radial growth was close to control in 2000–2011.  相似文献   

10.
《土壤污染防治法》的正式出台,标志着我国土壤污染防治工作由"现状治理"转向"风险预防",为此开展区域土壤重金属风险预警研究具有一定的理论与现实意义。以太湖沿岸某产粮县为研究对象,以2015年为基准年,运用重金属输入-输出通量模型和土壤环境负载容量法对研究区耕地土壤中的As、Hg、Cr、Cd、Pb 5种重金属15年(2030年)与35年(2050年)后的风险概率进行预警研究。研究结果表明:大气干湿沉降成为除As以外其他4种土壤重金属的主要来源,畜禽粪便、化肥投入与灌溉水也会在一定程度上影响土壤重金属输入;此外,研究区耕层土壤中As、Cr、Pb 3种重金属整体情况较为良好,Hg、Cd污染风险概率较高,主要分布在研究区中部的O镇、P镇。通过GIS技术与区域物质流通量模型的结合能够很好地对不同区域以及不同重金属污染类型的区域进行风险预警,这可以为土壤污染差别化管控策略的制定提供重要思路。  相似文献   

11.
Nowa days, ecological and cultural tourism, especially those ancient villages and towns in China, have attracted an increasing number of tourists because of their unique cultural features. However, rapid development of tourism brings economic benefits, but results in a series of problems that threaten further tourism development and protection of ancient towns, such as over-commercialization and tourism urbanization. Taking Longmen ancient town as an example, this paper presented a sustainable way of preserving and developing resources of ancient villages and towns. First, identify cultural features and the extent of ancient villages and towns, and find the approach through which a cultural landscape zoning can be applied. Second, define a cooperative function area to release the pressure on core areas and protect their authentic cultures by extending tourism space. Third, balance tourism development with traditional industries to enhance the sustainability of community economies.  相似文献   

12.
通过对昆山市14个区镇91个土壤样品中As、Cd、Cr、Cu、Pb、Ni、Hg、Zn 8种重金属测定分析,对该市耕地土壤重金属污染进行评价并进行重金属污染的影响因素分析.结果表明,昆山市耕地土壤存在不同程度的轻微污染,重金属Cd、Cr、Cu、Pb、Hg、Zn均超过国家土壤背景值,旱地、水田中均以Hg污染范围较广、变异系数较大.综合污染指数表现为水田(1.15)>旱地(1.00).区镇耕地重金属污染评价表明千灯、陆扬、石浦、锦溪、石牌处于警戒值之内,蓬朗、周庄、张浦、正仪、周市、巴城、淀山湖、花桥、陆家轻度污染;昆山市耕地土壤中重金属元素均未超过土壤环境基本容量,能够保证作物品质和农业持续发展.同时,研究表明区域重金属轻微污染具有复合污染的特性,Cd、Pb相关性最高(P=0.621 0), Pb与Hg、Cu、Zn、Cu与Cr也有相关性(0.438 7、0.426 0、0.350 9、0.394 0),区域重金属的轻微污染受人为因素影响显著,研究指出应加强对区域优先控制污染物Hg、次优先控制污染物Pb、Cd、Zn、Cu、Cr的控制与治理.  相似文献   

13.
科学剖析农用地生态效率时空差异及影响机制,对实现农用地利用与资源环境协调发展以及制定农业可持续发展政策具有重要的理论与实践意义。将农用地面源污染、碳排放作为非期望产出纳入农用地生态效率评价指标体系,借助SBM-Undesirable模型对1990~2017年江西省农用地生态效率进行测度并对其时空差异特征进行分析,在此基础上运用Tobit模型探讨相关因素的影响机制。结果表明:(1)1990~2017年间江西省农用地生态效率呈现"先下降后上升"的变化趋势,均值为0.749,总体呈现上升的趋势;(2)各设区市农用地生态效率空间格局演变轨迹呈现先下降后上升的扁平"U"型特征,高效率地区由"连片"分布向"点状"分布再向"连片"分布变化,空间格局趋于非均衡化发展;(3)农村居民人均可支配收入、复种指数、农村劳动力文化程度和劳均播种面积对农用地生态效率产生显著正影响,城乡收入差距则产生显著负影响。最后,从优化资源要素配置、加强农业科技创新应用、健全农村土地流转制度、摒弃过度依赖资源要素投入与环境污染的粗放型发展模式、走"精耕细作"和可持续发展的农业生态文明发展道路等方面提出了提高农用地生态效率的政策建议。  相似文献   

14.
A comparative study of the greater plantain seed progeny was performed with samples from cenopopulations growing for a long time under conditions of radioactive contamination (in the Eastern Ural Radioactive Trace, EURT) or chemical pollution (in the impact zone of the Nizhny Tagil Iron and Steel Works, NTMK). The progeny of plants from the NTMK zone had low viability but proved to be resistant to the additional impact of a “new” factor (acute γ-irradiation) as well as of the “habitual” factor (heavy metal toxicity). Plantain seeds from the EURT area showed high viability and low heavy metal and radiation resistance; i.e., no preadaptation effect was revealed. In experiments on growing plants from different cenopopulations in plot culture, samples from the EURT zone were characterized mainly by morphoses of generative organs, while samples from the NTMK area, by morphoses of vegetative organs.  相似文献   

15.
Spatial variation in the cellulolytic activity of the soil microflora during the growing season (from May to September) has been studied in spruce-fir forests exposed to emissions from the Middle Ural Copper-Smelting Plant. It has been shown that the average rate of decomposition of pure cellulose in polluted areas is significantly reduced, with its spatial variation being markedly increased. The spatial pattern of cellulolytic activity remains stable during the growing season, and the integrated parameters of frequency distributions in zones with different pollution levels change with time in the same direction.  相似文献   

16.
利用2008年1月~2012年12月期间成都市市区与其周边14个城镇的逐日空气污染指数(API)数据,采用去趋势互相关分析法(DCCA分析)研究区域城市间大气污染的相关性及其随时间演变规律。结果表明:成都市区与其周边城镇大气污染的空气污染存在一定程度的相关性,并且在不同的月份,相关性会随之发生变化。这种相关性具有长期持续特征,具体表现为在一定的时间尺度上成都市区与其周边城镇大气污染的相关性随时间的变化并不遵循经典的马尔可夫过程,即不随时间呈现指数快速衰减,而是以幂律形式随时间缓慢衰减。进一步,结合不同月份间区域大气平均流场的分布特征,探讨了DCCA分析结果的科学性。研究结果说明,在特定地理环境和气象条件控制下,成都市及其周边城市之间已经存在明显的相互输送和耦合作用,成都地区大气污染已由局地性污染转变为区域性大气污染。城市间污染物输送的长期相关影响机制极有可能在特定月份加重成都市区的空气污染状况,这在成都市区及其周边城镇的规划建设中必须加以特别重视  相似文献   

17.
Persistent organic pollutants (POPs) have aroused environmentalists and public concerns due to their toxicity, bioaccumulation and persistency in the environment. However, monitoring atmospheric POPs using conventional instrumental methods is difficult and expensive, and POP levels in air samples represent an instantaneous value at a sampling time. Biomonitoring methods can overcome this limitation, because biomonitors can accumulate POPs, serve as long-term integrators of POPs and provide reliable information to assess the impact of pollutants on the biota and various ecosystems. Recently, mosses are increasingly employed to monitor atmospheric POPs. Mosses have been applied to indicate POP pollution levels in the remote continent of Antarctica, trace distribution of POPs in the vicinity of pollution sources, describe the spatial patterns at the regional scale, and monitor the changes in the pollution intensity along time. In the future, many aspects need to be improved and strengthened: (i) the relationship between the concentrations of POPs in mosses and in the atmosphere (different size particulates and vapor phases); and (ii) the application of biomonitoring with mosses in human health studies.  相似文献   

18.
The concentrations of nickel and copper were determined in mosses Hylocomium splendens and Pleurozium schreberi sampled in 1991 and 2011 at the same sites in the Lapland State Biosphere Reserve located in the impact area of atmospheric emissions from the Severonickel Smelter Combine (Monchegorsk, Murmansk Region, Russia). Both moss species have been confirmed to adequately reflect the levels of aerial technogenic load and can be used equally to monitor environmental pollution from heavy metals. It has been statistically proven that not only the volume of atmospheric emissions of polymetallic dust and the distance to the pollution source affect the concentrations of heavy metals in the studied moss species, but the wind rose and relief are also of importance.  相似文献   

19.
Under the globalization, the coastal China becomes a hot area of the international manufacturing investment due to its priority location, excellent environment, lower labor and land costs, etc. However, the fast industrialization has aroused the great demolishment to the local ecological environment. For example, the heavy water eutrophication in Taihu Lake has affected the source of drinking water for the cities around the lake. Anyway, in order to keep the economic increase and reduce the resource ex- pense and pollution at the same time, it is necessary to encourage the greening of industrial enterprises actively for sustainable de- velopment. On the basis of the investigation of industrial enter- prises in Wuxi city within Taihu Basin, the relatively developed region in coastal China, this paper analyzed the development process of green industry. This article concluded that governmen- tal principal is the main pressure for enterprises to protect envi- ronment while the market factor plays a part role. Moreover, en- terprises in the high technology development zone work better in environmental protection than those in the villages and towns, while the large enterprises work better than those small enterprises.  相似文献   

20.
针对三峡工程蓄水和移民搬迁对库首地区农业生产和居民生活造成的影响,对移民安置前后三峡库首地区的秭归、兴山、巴东等县乡镇土地资源状况进行了统计分析,并选择典型乡镇移民户作为研究对象,实地调查了移民安置区移民户的经济收支情况及其对移民安置的满意度。结果表明:三峡工程蓄水后,库区低海拔地区耕地淹没,农村可用耕地总量减少,人均耕地也有所减少,人地资源矛盾比较突出。移民主要收入来源为劳务、种植业和养殖业收入,其中劳务收入比例较大,农户家庭经济支出主要是以生活支出为主,移民搬迁对部分农民经济收入产生较大影响。移民搬迁以后,库区农村的居住环境、住宅条件、生活条件和交通条件均较移民前有明显改善,农户普遍比较满意。库首地区的移民政策落实较好,大部分人对未来发展充满信心,对三峡工程表示支持和肯定。搬迁安置对农村生态环境状况产生了影响,存在自然灾害和病虫害增多,农村废弃物处理设施不足等问题,应当引起政府对库区生态环境问题的足够重视。〖  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号