双季稻蚕区梯田埂地综合利用模式

一、现状田埂地具有一般土地资源的属性。由于它位于田边,与水稻田相比土壤性状特殊,面积相对狭小,易被忽视。但我国山地丘陵广布,梯田数量多,埂地资源丰富。长期以来,由于人们对梯田埂地的利用认识不足,习惯扩大田地面积,挖窄埂地,铲除田埂斜坡植被,导致了扩大田地面积→梯田埂变窄→漏水严重→水土流失加剧→生产成本增加→收益下降→扩大开垦的恶性循环。一些地方人多、路     

黑龙江宜农荒地资源的基本特征与开发潜力

黑龙江省是我国农业开发历史较晚的地区之一，自1897年以来，黑龙江省开垦的耕地从5330ha增加到1994年底的890．9万ha，成为我国重要的商品粮基地之一，供给全国约1／5的商品粮。目前，黑龙江省尚有大量可供开垦的宜农荒地资源，因此，分析其开发潜力可为今后实施开发提供依据。1宜农荒地数量与分布1．l宜农荒地数量大、类型多宜农荒地广义上包括宜于开辟为农用土地的荒地，即宜耕地、宜林地、宜牧地等；狭义上指宜于开垦作为耕地的荒地，本文宜农荒地的含义为后者。它主要需满足以下条件：土地温度能满足当地适种作物生长发育的要求，有适…     

略论清代自然资源的保护与利用

清代在水土资源、林木资源、矿产资源的保护与利用等方面采取了积极有效的措施，包括开垦土地、兴修水利、发展生态农业、植树造林、加强法制、设立环保机构等。     

城市土地可持续利用评价研究——以南京市为例

城市土地利用系统是一个典型的“生态-经济-社会”复合系统，对其可持续利用水平进行综合评价涉及到的指标多而复杂。从影响城市土地可持续利用的资源、社会、环境和经济等方面综合考虑，选取了耕地面积、粮食产量和年末总人口等15个相关指标，运用主成分分析方法，对南京市1995-2002年的土地利用状况进行综合评价。结果表明，用主成分分析方法对城市土地可持续利用水平进行综合评价，其评价结果与南京市的实际相符，具有一定的实用性和可操作性。     

利用Landsat7反演的亮温与土地覆盖类型相关性分析

随着城市人口的急剧增加,城市建筑规模迅速膨胀,大量热源集中排放,产生了城市内部温度明显高于郊区的特殊城市气候现象,即“热岛效应”.以安徽省芜湖市为研究区域,采用GIS叠加分析方法、缓冲区分析方法进行地表辐射亮温与土地覆盖类型的相关性研究.研究结果表明,辐射亮温与地表类型有明显的相关关系,建筑与辐射亮温的相关系数为0.87,植被、水体与辐射亮温的相关系数分别为0.59、0.78.人工建筑因素是产生热岛效应的主要原因之一,加大植被、水体在城市土地用地中的比重,是控制城市热岛效应行之有效的方法,而且利用辐射亮温图可很好地指示城市土地覆盖类型在时间上和空间上的变化.     

有色金属矿山尾矿库复垦与生态恢复技术

由北京矿冶研究总院开发、北京环境保护产业协会推荐的有色金属矿山尾矿库复垦与生态恢复技术适用于有色金属和其它矿山尾矿库、排土场、渣场、露天采矿坑等被破坏、损毁土地使用价值的恢复。主要技术内容一、基本原理对矿业开发形成的尾矿库、排土场、渣场、露天采矿坑等损毁压占的土地，采取综合整治措施，经过工程复垦、生物复垦和监测、管理、修复三个阶段，使其变成农田、林地、草场、鱼塘，恢复土地的使用价值和环境生态。二、技术关键该技术突破单一覆土工程和植被的传统复垦模式，以安全、稳定、可持续利用和生态恢复为目标组织水工…     

吉林省城市化进程中土地资源的可持续利用分析

“十一五”期间,吉林省城市化稳步发展,但在快速城市化的同时,土地利用方面出现了一些问题.从城市化角度出发,研究吉林省城市化发展与土地利用之间的内在联系,认为其存在的农业大省与城市扩展中占用耕地矛盾并存、土地集约利用水平偏低且浪费现象严重、土地利用类型变更混乱、土地利用环境问题严重等问题,提出解决城市化进程中土地可持续利用的对策.     

对我区土地资源可持续利用的一点思考

通过对土地资源可持续利用意义的分析，结合我区土地资源利用的现状，阐述我区土地资源利用面临的各种问题及解决的方法，提出一些急需解决的理论问题及实际工作中面临的难题；同时也提出了一些解决问题的对策和土地可持续利用的思路。     

空间互动视角下的土地集约利用碳排放效应分析北大核心

土地集约利用和碳排放是经济社会可持续发展的重要途径和约束条件,解构两者之间的关系可为土地资源可持续利用和实现“碳中和”目标提供科学依据。通过建立空间杜宾模型,解读空间互动视角下1995—2018年我国省际层面土地集约利用碳排放效应特征。结果表明:①地均碳排放存在显著负向互动影响,省际之间碳减排呈现零和博弈的特点,表现为邻省的地均碳排放每下降1个百分点,将导致本省地均碳排放上升0.232个百分点。②土地集约利用与地均碳排放之间呈“倒U型”曲线关系,因多数省份土地集约利用水平较低,尚未跨越“倒U型”曲线拐点,直接效应表现为本省的土地集约利用水平提升促进本省的地均碳排放量增加,土地集约利用抑制邻省碳排放的空间溢出效应不明显。基于研究结论,提升土地集约利用水平将有利于发挥土地集约利用碳减排效应和空间溢出效应,同时区域联动机制对于土地资源的可持续利用和双碳目标的实现可起到事半功倍的效果。     

全域土地综合整治背景下的乡村“三生空间”治理路径——以山水乡旅乡村振兴示范走廊为例

全域土地综合整治是土地整治的发展演变与创新探索，是生态文明背景下缓解土地资源供需矛盾、推进农用地、建设用地集约高效利用，强化生态空间保护与修复的重要手段。三生空间涵盖了乡村发展所需的空间类型，成为推动生态文明建设、优化国土空间格局、实施乡村振兴战略的载体。着力探讨全域土地综合整治与三生空间逻辑关系，并以全域土地综合整治为手段，探索新时期乡村三生空间治理路径，提出以全域整治盘活存量用地、建立用地指标纵向传导体系、强化生态全要素修复和注重“人-地-财-社区”的制度保障设计等规划策略，以期达到优化乡村空间布局、促进资源要素流动，推动全域全要素精细化管理的目的，以期为同类地区乡村发展提供新思路。     

回顾 总结 部署

3月26日至3月28日,备受关注的2003年度中国石油集团公司安全生产环境保护职业健康工作会议在青岛召开。 会议期间王海森主任做了题为“与时俱进,开拓创新,推进安全环境健康工作再上新水平”的报告,指出此次会议的主要任务是:总结回顾过去三年安全生产,环境保护和职业健康工作,分析形势,安排部署2003年工作,推进安全环境健康工作再上新水平。回顾三年的成绩,主要体现在:安全环保健康目标和责任制不断落实;安全环保健康规章制度逐步完善;安全环保机构得到加强和充实;健康安全环境管理体系全面推进;建设项目环境管理规范进行;安全环保科技创新…     

Sustainability,eco-efficiency,life-cycle management,and business strategy

This article outlines some of the rationale for integrating environment and sustainablility issues into core business practises and provides some guidance on how companies can begin to take a strategic view when selecting environmental management tools. Two of these tools, life cycle management and eco-efficiency, are outlined in brief.© 1999 Five Wind International. Reprinted with permission by John Wiley & Sons, Inc.     

Atrazine, isoproturon, mecoprop, 2,4-D, and bentazone adsorption onto iron oxides

Iron oxides are important components influencing the adsorption of various inorganic and organic compounds in soils and sediments. In this study the adsorption on iron oxides of nonionic and ionic pesticides was determined as a function of solution pH, ionic strength, and pesticide concentration. The investigated iron oxides included two-line ferrihydrite, goethite, and lepidocrocite. Selected pesticides comprised atrazine (6-chloro-N2-ethyl-N4-isopropyl-1,3,5-triazine-2,4-diamine), isoproturon [3-(4-isopropylphenyl)-1,1-dimethylurea)], mecoprop [(RS)-2-(4-chloro-2-methylphenoxy)propionic acid], 2,4-D (2,4-dichlorophenoxyacetic acid), and bentazone [3-isopropyl-1H-2,1,3-benzothiadiazin-4(3H)-one 2,2-dioxide]. The adsorption of the nonionic pesticides (atrazine and isoproturon) was insignificant, whereas the adsorption of the acidic pesticides (mecoprop, 2,4-D, and bentazone) was significant on all investigated iron oxides. The adsorption capacity increased with decreasing pH, with maximum adsorption reached close to the pKa values. The addition of CaCl2 in concentrations from 0.0025 to 0.01 M caused the adsorption capacity to diminish. The adsorption of bentazone was significantly lower than the adsorption of mecoprop and 2,4-D, illustrating the importance of a carboxyl group in the pesticide structure. The adsorption capacity on the iron oxides increased in the order: lepidocrocite < goethite < two-line ferrihydrite. The maximum adsorption capacities of meco-prop and 2,4-D on goethite were found to be equivalent to the site density of singly coordinated hydroxyl groups on the faces of the dominant (110) form, suggesting that singly coordinated hydroxyl groups are responsible for adsorption. Differences in adsorption capacities between iron oxides can be explained by differences in the surface site density of singly coordinated hydroxyl groups. The maximum measured adsorption capacity of mecoprop on two-line ferrihydrite was equivalent to 0.2 mol/mol Fe.     

Tillage, intercrop, and controlled drainage-subirrigation influence atrazine, metribuzin, and metolachlor loss

Atrazine (6-chloro-N2-ethyl-N4-isopropyl-1,3,5-triazine-2,4-diamine) and metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide] have been found with increasing occurrence in rivers and streams. Their continued use will require changes in agricultural practices. We compared water quality from four crop-tillage treatments: (i) conventional moldboard plow (MB), (ii) MB with ryegrass (Lolium multiflorum Lam.) intercrop (IC), (iii) soil saver (SS), and (iv) SS + IC; and two drainage control treatments, drained (D) and controlled drainage-subirrigation (CDS). Atrazine (1.1 kg a.i. ha-1), metribuzin [4-amino-6-(1,1-dimethylethyl)-3-(methylthio)-1,2,4-triazine-5(4H)-one] (0.5 kg a.i. ha-1), and metolachlor (1.68 kg a.i. ha-1) were applied preemergence in a band over seeded corn (Zea mays L.) rows. Herbicide concentration and losses were monitored from 1992 to spring 1995. Annual herbicide losses ranged from < 0.3 to 2.7% of application. Crop-tillage treatment influenced herbicide loss in 1992 but not in 1993 or 1994, whereas CDS affected partitioning of losses in most years. In 1992, SS + IC reduced herbicide loss in tile drains and surface runoff by 46 to 49% compared with MB. The intercrop reduced surface runoff, which reduced herbicide transport. Controlled drainage-subirrigation increased herbicide loss in surface runoff but decreased loss through tile drainage so that total herbicide loss did not differ between drainage treatments. Desethyl atrazine [6-chloro-N-(1-methylethyl)-1,3,5-triazine-2,4-diamine] comprised 7 to 39% of the total triazine loss.     

Environmental concentrations of agricultural herbicides in Saskatchewan, Canada: bromoxynil, dicamba, diclofop, MCPA, and trifluralin

Herbicides are the most commonly used group of agricultural pesticides on the Canadian Prairies and, in 1990, more than 20000 Mg of herbicides were applied in the provinces of Alberta, Saskatchewan, and Manitoba. The present paper reports on environmental concentrations of five herbicides currently used in the prairie region. The herbicides bromoxynil [3,5-dibromo-4-hydroxy-benzonitrile], dicamba [3,6-dichloro-o-anisic acid], diclofop [(RS)-2-[4-(2,4-dichlorophenoxy)-phenoxy]propanoic acid], MCPA [(4-chloro-2-methylphenoxy)acetic acid], and trifluralin [alpha,alpha,alpha-trifluoro-2,6-dinitro-N,N-isopropyl-p-toluidine] were measured in the atmosphere, bulk atmospheric deposits, surface film, and dugout (pond) water at two sites near Regina, Saskatchewan, during 1989 and 1990. All five herbicides were detected in air and surface film and all but trifluralin were detected in the bulk atmospheric deposits and dugout water. Trifluralin was most frequently detected in air (79% of samples) whereas bromoxynil was present in maximum concentration (4.2 ng m(-3)). MCPA was present in maximum levels in bulk atmospheric (wet plus dry) deposits (2350 ng m(-2) d(-1)), surface film (390 ng m(-2)), and dugout water (330 ng L(-1)), whereas dicamba was most frequently detected in surface film (47%) and dugout water (97%). The highest quantities of the herbicides tended to be present during or immediately after the time of regional application.