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1.
论城市水土保持与生态城市建设 总被引：1，自引：0，他引：1
刘文学 《水土保持应用技术》2014,(6):27-29
根据城市水土保持的内涵及特点和生态城市建设的内涵及特性,论述了城市水土保持与生态城市建设的相互关系,城市水土保持为生态城市建设提供丰富的水资源以及适宜植被生长的土壤;生态城市建设可以为城市提供良好的生态植被,改善城市小气候。同时,提出了城市水土保持与生态城市建设过程中人为造成和自然形成的5个主要问题,并就如何解决好5个问题推出了相对应的5项城市水土保持主要技术方法。 相似文献
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山东省城市水土保持工作的探索与实践 总被引：1，自引：0，他引：1
近5年来,山东省对城市水土保持生态环境建设进行了积极探索和实践,在预防监督、人文和谐乐园建设、投融资机制改革和团结治水等方面取得了显著成效。青岛、烟台、东营3市被水利部命名为全国水土保持生态环境建设示范城市,滨州市也顺利通过了全国水土保持生态环境建设示范城市初验。全国水土保持生态环境建设示范城市作为一个城市的高品位象征,其社会影响力不断提高,有力地推动了人与自然的和谐相处。 相似文献
3.
永春县城市水土保持生态环境建设试点工作主要做法与成效 总被引：1，自引：1，他引：0
城市水土保持生态环境建设是针对城市水土流失提出的，是市政建设的重要组成部分。永春县城区于1998年被福建省水保委列为城市水土保持生态环境试点。3年多来，该县以完善城市功能建设及城区净化、绿化、美化、香化为重点，以城区防洪工程、示范小区建设为主线，积极探索新形势下城市水土保持生态环境建设路子，取得了较好的成效，2001年12月通过了福建省水保委验收。本就该县的做法及成效进行分析、总结。 相似文献
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张华庚 《水土保持应用技术》2011,(5):23-24
随着城市化的迅速发展,人口的急剧膨胀,城市基础设施建设与开发建设项目逐渐增多,破坏了原地貌,损毁了原有的地表植被,城市工业园区的尾气及居民燃气大量增加形成的酸雨腐蚀各种措施并污染饮用水,严重影响人们的身心健康,阻碍城市的可持续发展。为此,通过对城市水土保持的特点、危害以及造成城市水土流失因素的分析,对城市水土保持与城市生态建设提出几点建议,同时指出,城市水土保持是实现生态城市建设的基础,也是当前城市建设的重点。 相似文献
5.
城市水土保持规划与城市可持续发展 总被引：2，自引：2，他引：2
城市水土流失是一种特殊的水土流失类型,具有形式多样,突发性强、治理难度大等特点。城市水土流失严重影响城市生态环境,制约着城市化进程和城市可持续发展。城市水土保持是水土保持工作的重要组成部分,是针对城市化过程中引发的严重的水土流失而提出来的,城市水土保持规划是以城市功能为中心,为改善城市生态系统的结构和功能及城市可持续发展服务。把城市水土保持规划纳入城市总体规划,做好城市水土保持工作,可使城市发展步入可持续发展的轨道。 相似文献
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自20世纪90年代我国提出和开展城市水土保持工作以来,城市水土保持工作取得了显著成效:一是拓宽了水土保持工作领域,二是建成了一批城市生态景观,三是控制了城市建设中的水土流失,四是提高了公众的水土保持意识。各地在城市水土保持工作实践中,探索和总结出了许多行之有效的好做法。当前和今后一段时期,要深刻领会搞好城市水土保持工作的重要意义,继续夯实城市水土保持工作基础,全面落实水土保持"三同时"制度,着力加快水土流失治理进度,积极创建水土保持生态文明城市,不断引入新理念、新技术、新工艺,强化宣传,努力营造城市水土保持良好氛围。对城市水土保持专委会的工作提出了要求。 相似文献
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城市水土保持中“海绵城市”理念的应用 总被引：1，自引：0，他引：1
随着我国城市化进程的不断加快,城市建设引发的水土流失已经逐步成为影响人们环境、生活的主要问题。在控制城市水土流失问题上,城市水土保持起到了至关重要的作用。近年来,在城市水土保持建设过程中越来越多的考虑到了"海绵城市"理念,通过列举几种现阶段利用较广泛的水土保持措施,帮助解读海绵城市的概念以及与城市水土保持之间共性和个性的关系。 相似文献
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随着城市化的迅猛推进,城市水土流失及潜在危害日益严重.1997年,水利部将涪陵列为全国水土保持生态环境建设示范城市后,相关部门积极配合,认真贯彻执行水土保持法,将水土保持与旧城区改造、城市建设紧密结合,城市生态环境得到明显改善. 相似文献
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城市化进程日益加快,城市水土保持工作愈显重要。回顾半年多来乐山市开展城市水土保持生态环境建设工作的进展,并提出了今后水土保持工作必须搞好水保法律宣传,加强领导,建立执法队伍等作法。 相似文献
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中国华北地区近40年物候春季变化 总被引：17，自引：4，他引：17
根据华北地区7个观测站物候资料,分析了华北地区1963-1996年及北京1963-2005年物候春季的变化特征及其与气温的关系。结果表明:华北地区的物候春季有明显提早来临的趋势,而造成这一变化的主要因素是本地区近40 a来冬春季气温的明显上升。其中1963-1996年间华北地区1-3月及4月的平均气温分别上升了2.3℃与1.7℃,物候春季起止日期分别提前了9d和4d,因而使得春季长度也延长了5d;北京1963-2003年间1-3月及4月的平均气温分别上升了3.5℃与2.6℃,物候春季的起止日期分别提前了11d和10d,但春季长度没有明显变化。 相似文献
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Howard B. Ross 《Water, air, and soil pollution》1987,36(3-4):349-363
Trace metals (Cd, Cu, Fe, Mn, Pb, and Zn) concentrations in atmospheric precipitation have been routinely monitored in Sweden since the autumn of 1983. Concentrations are highest in southern Sweden and decrease northward. It is postulated that the long range transport of anthropogenic pollutants from the rest of Europe is the major source of Cd, Pb, and Zn in precipitation. Evidence for this hypothesis is that enrichment factors indicate anthropogenic origin, and Swedish atmospheric emissions of Zn and Cd are 2 to 3 times smaller than deposition fluxes. Also, Cd, Pb, and Zn concentrations are correlated in both space and time and are also well correlated with exSO4 +, a substance known to be of anthropogenic origin transported long distances. 相似文献
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Water, Air, & Soil Pollution - Epiphytic lichens were sampled in a Dutch national monitoring survey, which was carried out twice within 5 yr. The samples were analyzed by neutron activation... 相似文献
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Sediment denitrification in waterways in a rice-paddy-dominated watershed in eastern China 总被引：1，自引：0，他引：1
Xiaobo Li Yongqiu Xia Yuefei Li Todd M. Kana Sonoko D. Kimura Masanori Saito Xiaoyuan Yan 《Journal of Soils and Sediments》2013,13(4):783-792
Purpose
Rice-paddy-dominated watersheds in eastern China are intensively cultivated, and lands with two crops receive as much as 550–600 kg?ha–1?year–1 of nitrogen (N), mainly through the addition of N-based fertilizers. However, stream N concentrations have been found to be relatively low. Waterways in the watersheds are assumed to be effective “sinks” for N, minimizing its downstream movement. We directly measured net sediment denitrification rates in three types of waterways (ponds, streams/rivers, and a reservoir) and determined the key factors that control net sediment denitrification. Such information is essential for evaluating the impact of the agricultural N cycle on the quality of surface water.Materials and methods
The pond–stream–reservoir continuum was sampled every 2 months at nine sites in an agricultural watershed between November 2010 and December 2011. Net sediment N2 fluxes/net sediment denitrification rates were determined by membrane inlet mass spectrometry and the N2/Ar technique. A suite of parameters known to influence denitrification were also measured.Results and discussion
Net denitrification rates ranged between 28.2?±?18.2 and 674.3?±?314.5 μmol N2–N?m–2?h–1 for the streams, 23.7?±?23.9 and 121.2?±?38.7 μmol N2–N?m–2?h–1 for the ponds, and 41.8?±?17.7 and 239.3?±?49.8 μmol N2–N?m–2?h–1 for the reservoir. The mean net denitrification rate of the stream sites (173.2?±?248.4 μmol N2–N?m–2?h–1) was significantly higher (p?<?0.001) than that of the pond sites (48.3?±?44.5 μmol N2–N?m–2?h–1), and the three types of waterways all had significantly higher (p?<?0.01) mean net denitrification rates in summer than in other seasons. Linear regression and linear mixed effect model analysis showed that nitrate (NO3 ?–N) concentration in surface water was the primary controlling factor for net sediment denitrification, followed by water temperature. Using monitoring data on NO3 ?–N concentrations and temperature of the surface water of waterways and an established linear mixed effect model, total N removed through net sediment denitrification in the pond–stream–reservoir continuum was estimated at 46.8?±?24.0 t?year–1 from July 2007 to June 2009, which was comparable with earlier estimates based on the mass balance method (34.3?±?12.7 t?year–1), and accounted for 83.4 % of the total aquatic N. However, the total aquatic N was only 4.4 % of the total N input to the watershed, and thus most of the surplus N in the watershed was likely to be either denitrified or stored in soil.Conclusions
High doses of N in a rice-paddy-dominated watershed did not lead to high stream N concentrations due to limited input of N into waterways and the high efficiency of waterways in removing N through denitrification. 相似文献15.
天津半干旱地区不同种植年限菜田土壤微生物变化特征的研究 总被引：13，自引：1，他引：12
对天津周边半干旱地区不同种植年限的菜田土壤微生物状况调查研究表明 ,该地区土壤微生物以细菌为主 ,夏季微生物总量大大高于冬季 ;随着种菜年限的增加 ,耕层和亚耕层微生物总量都有增加趋势 ,其中细菌和放线菌增加明显 ,真菌有下降趋势 ;真菌类群分析表明 ,少数纤维素分解菌 ,如青霉 (Penicillium)、木霉 (Trichoderma)等为优势菌 ,而糖和木质素分解菌仅占少数。用尖孢镰刀霉 (Fusariumuoxysporum)、大肠杆菌 (Escherichia coli)接种不同种菜年限土壤 ,检测土壤拮抗菌状况发现 ,拮抗菌仅在种植年限长的老菜田的放线菌中发现。表明北方半干旱地区菜田土壤细菌为优势菌 ,主要存在于土壤微孔隙中 ;而适于生活在土壤疏松大孔隙中的真菌数量极少。应注意土壤结构的改良 ,为丰富土壤微生物提供良好的生态环境 相似文献
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天津半干旱地区不同种植年限菜田土壤微生物变化特征的研究 总被引：3，自引：0，他引：3
对天津周边半干旱地区不同种植年限的菜田土壤微生物状况调查研究表明 ,该地区土壤微生物以细菌为主 ,夏季微生物总量大大高于冬季 ;随着种菜年限的增加 ,耕层和亚耕层微生物总量都有增加趋势 ,其中细菌和放线菌增加明显 ,真菌有下降趋势 ;真菌类群分析表明 ,少数纤维素分解菌 ,如青霉 (Penicillium)、木霉 (Trichoderma)等为优势菌 ,而糖和木质素分解菌仅占少数。用尖孢镰刀霉 (Fusariumuoxysporum)、大肠杆菌 (Escherichia coli)接种不同种菜年限土壤 ,检测土壤拮抗菌状况发现 ,拮抗菌仅在种植年限长的老菜田的放线菌中发现。表明北方半干旱地区菜田土壤细菌为优势菌 ,主要存在于土壤微孔隙中 ;而适于生活在土壤疏松大孔隙中的真菌数量极少。应注意土壤结构的改良 ,为丰富土壤微生物提供良好的生态环境 相似文献
17.
Phytoremediation is an emerging technology based on the use of green plants to remove, contain, inactivate or destroy harmful
environmental pollutants. Recent developments in Europe and the USA show that the approach is somewhat different on both sides
of the Atlantic. In Europe, phytoremediation has more basically been research driven and, based on the outcomes, applications
have been envisaged. By contrast, the approach in the USA is more application and experience driven. In spite of a growing
track record of commercial success, more demonstration projects are needed to prove that phytoremediation is effective in
order to rigorously measure its underlying economics, and to expand its applications. More fundamental research is also required
to better understand the complex interactions between pollutants, soil, plant roots and micro-organisms at the rhizosphere
level, to increase the bioavailability of pollutants, to fully exploit the metabolic diversity of plants and, thus, to successfully
implement this new green technology. 相似文献
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Shu Wang 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2017,67(7):583-589
Proteolytic bacterial communities, which mineralize organic nitrogen, play a key role in agricultural systems. In this study, alkaline metalloprotease (apr) gene fragments from proteolytic bacteria were investigated in bulk and rhizosphere paddy soil from four fields under organic management (for 2, 3, 5, and 9 years), and from one field under conventional management (for 2 years). We analyzed the abundance and structure of the proteolytic bacterial communities using real-time quantitative PCR and denaturing gradient gel electrophoresis. Our results showed that the abundance of proteolytic bacteria ranged from 1.57?×?108 to 8.02?×?108?copies/g of soil. In addition, the abundance of the proteolytic bacteria in the paddy soils under organic management was significantly higher than those in the paddy soil under conventional management. Moreover, the gene copy numbers in the rhizosphere soils were significantly higher than those in the bulk soils. The abundance of proteolytic bacteria tended to increase with the duration of organic management, with the highest abundance being found in the soil that had been under organic management for 5 years. However, the proteolytic bacteria communities in the paddy soils were not significantly affected by management practices. Phylogeny analysis showed that all gel bands obtained represented genes from Pseudomonas. Additionally, correlation analysis and canonical correspondence analysis showed that C/N, C, and N were important factors that influenced the abundance and community structure of the proteolytic bacteria. These results suggest that proteolytic bacteria are indicators in organic management systems, depolymerize organic N and hence maintain soil sustainability.Abbreviations: CM: conventional management; OM: organic management; DGGE: denaturing gradient gel electrophoresis; qPCR: real-time quantitative PCR detecting system; COFCC: China organic food certification center; CCA: canonical correspondence analysis 相似文献