三峡库区水土流失类型划分及防治对策

在对三峡库区水土流失现状调查的基础上,按照相似性与差异性原则对库区水土流失进行了类型划分,将三峡库区划分为三峡库区东段中低山、中段低山丘陵、西段低山丘陵3个水土流失类型一级区,将3个一级区又划分为9个二级水土流失类型区,并结合各水土流失区域特征提出了分区进行水土流失防治的对策。     

城市水土流失对城市环境的影响及其对策

近年来,随着我国城市化进程的加快,我国的城市水土流失问题日趋严重,且严重影响了城市环境,这越来越引起了人们的重视.本文首先介绍了城市水土流失和城市环境的概念,进而阐述了城市水土流失对城市环境的影响及危害和城市水土流失产生的原因,并在此基础上提出了对策和建议.     

城市水土流失监测探讨

随着城市化进程的加快,我国的水土资源和环境等问题日益凸显。目前,我国对城市非点源污染的系统监测还处于起步阶段,对城市水土流失的监测还未系统开展。通过分析城市水土流失及污染物的特征,探讨引入城市水土流失监测,对城市地表径流量及TP、TN、COD等污染物流失量进行系统监测,以期能完善水土流失数据库。通过实时监测和调查,利用小区域的水土流失数据,应用"3S"技术、水土流失数据管理系统等先进技术手段,测算当地城市水土流失情况,为城市有效保护水土资源和控制非点源污染提供基础信息,为城市的发展决策提供切实可靠的数据依据。     

浅谈城市水土保持

由于我国城镇化建设速度加快,城市建设过程中不可避免地产生水土流失。本文就城市水土流失及水土保持的概念进行简要阐述,并对城市水土流失形式及其危害进行概括描述,认为城市水土流失可能引起生态失调、资源衰退、基础设施破坏和诱发地质灾害等。针对城市建设功能区划和地形等因素划分水土流失防治类型,根据不同区域、不同阶段的水土流失特点,提出了相应的水土流失防治措施,并指出建立健全城市水土保持规章,完善"三同时"制度,落实"三权",加强队伍建设,加大城市水土保持宣传和执法力度,加强经费投入和技术创新的重要性。     

铁岭市城市水土保持治理模式初探

铁岭城市水土保持以治理龙首山水土流失为中心 ,在城市建设上提出发展“山在城中、水穿市区、城中有山、城山相连”山水特色城的实施方案。近山绿化人造景观秀 ,造林种草鸟语花香人好歇 ;环路绿荫柳成行 ,浆砌护坡植物为屏障 ;城区步道釉砖铺地 ,广场旷地植树栽花铺草坪 ;绿色通道绿社区 ,林网防沙美化环境。通过采取不同的水土流失治理模式 ,并结合城市基础设施建设 ,取得较好效果     

黑龙江省东部低山丘陵区水土流失现状危害及发展趋势

黑龙江省东部低山丘陵区面积占黑龙江省总面积的25.3%,水土流失面积占全省水土流失总面积的41%,属黑龙江省水土流失严重区域。通过对黑龙江省第2次和第3次土壤侵蚀遥感调查成果进行分析总结,确定近5 a黑龙江省东部低山丘陵区一小部分水土流失土地得到了有效治理和开发利用,大部分水土流失土地在发展、流失程度在加重。具体表现为轻度水土流失面积在减少,中度、强度侵蚀水土流失土地在扩大。     

城市水土流失与环境治理

水土流失已被国际公认为影响环境的四大公害之一，黄土高原是我国水土流失最严重的区域。该对黄土高原山区城市水土流失的自然环境、成因和特点及对城市环境的危害进行了探讨，在此基础上提出了防治对策与建议。     

哈尔滨市城市水土保持问题探讨

近年来,随着哈尔滨市城市的不断扩张,大量的土地被开发利用,人们一度忽视了城市水土流失的危害,随意倾倒建筑垃圾,破坏了大量的地表植被,引起了严重的人为水土流失,对社会经济、生态景观、河流水质及防洪安全和居民生产生活等方面造成了较大的危害。针对这些危害和水土流失成因,结合哈尔滨市实际情况,从自然因素和人为因素两个方面分析了城市水土流失的成因。从城市风景区、开发建设项目、弃土弃渣、表土及临时堆土、城市河道、饮用水源地、完善立法等方面提出了治理城市水土流失的对策。     

鲁皖成品油管道工程山东段水土保持监测与评价

系统介绍了鲁皖成品油管道工程山东段水土保持监测的范围、内容、方法、时段和频次等,并对工程区内的水土流失动态变化、水土流失防治措施实施情况及效果等监测结果进行了分析和评价。研究表明,通过开展水土保持监测,可及时掌握项目区内水土流失的状况及动态变化,并确保该工程水土保持措施功能的正常发挥。     

中国城市水土流失的现状、对策及研究展望——以广东省深圳市为例

[目的]总结城市水土流失的概念、危害、成因、特点和防治对策,分析城市水土保持工作存在的问题和未来研究方向,旨在为中国城市水土流失治理及研究工作提供参考依据。[方法]根据多年的研究工作经验和文献资料,综合分析国内外城市水土流失及水土保持研究的成果。[结果](1)城市水土流失的概念蕴涵自然和人为两种动力,水和土两个流失主体,城市和周边及地表与地下两类分布空间;(2)城市水土流失危害主要包括管道淤积、风沙扬尘、水源污染、资源衰退、环境破坏等多方面;(3)城市水土流失防治对策主要包括法律、机制、宣传、监管、兼治和科研等6个方面。[结论]人们对城市水土流失的认识尚存不足,城市水土保持理论、技术及法规体系有待完善。城市水土流失及城市水土保持工作应从理论研究、应用优化以及经验推广等方面深入开展。     

安阳市水保工程建管方式及存在的问题与建议

安阳市近10年来建成的水土保持工程的主要建设管理方式可分为3种,即:乡村组织治理,完成后分配给农户分散经营;乡村组织治理,由村成立专业队代表村集体管理;把小流域或荒山承包给个体或私人经济组织,由其自行治理和经营管护。3种建管方式中以后者为最优,其经济效益是分散经营管理的5倍、专业队经营管理的3.5倍。针对水保工程建设管理中存在的问题和适应农村税费改革等要求,提出了加快安阳市水保生态建设的建议。     

我国滑坡、崩塌的区域特征、成因分析及其防御

论述了我国滑坡、崩塌的区域分布特征,滑坡和崩塌的危害程度,滑坡和崩塌类型和成因分析,并且提出了灾害的防御措施,以期达到环境保护成为社会发展过程中的一个重要组成部分。     

生产建设项目水土保持“天地一体化”监管存在问题及建议

根据"天地一体化"技术在生产建设项目水土保持监管中的应用情况,对"天地一体化"技术在水土保持信息化应用中存在的防治责任范围图件不规范、合规性鉴定困难、未批先建等问题进行了归纳总结,并提出相应的建议,以期能为"天地一体化"水土保持监管工作逐步走向成熟提供参考,全面提升水土保持信息化建设水平,加快推进水土保持监管信息化进程。     

濂溪区水土保持区划与防治布局研究

水土保持区划可为区域水土保持规划与宏观管理、水土保持生态文明建设提供重要的参考。在《江西省水土保持区划及防治布局研究》确立的原则与方法的基础上,根据全国、全省和九江市水土保持区划划分方法,分析濂溪区各乡镇地形地貌、水土流失特点、水土流失防治及经济社会发展等的区域差异,将全区划分为城市人居环境维护区、平原农田防护水质维护区、丘陵保土生态维护区3个五级区,同时基于水土保持功能,提出了各分区的详细水土流失防治布局,为濂溪区及其他区域的水土保持规划与宏观决策,加快推进各地生态文明建设提供重要的参考和借鉴。     

Hydroxy-Al complexes of montmorillonite and vermiculite and identification of intergrades of montmorillonite-chlorite and vermiculite-chlorite in soils

Much evidence has indicated that the occurrence of montmorillonite and vermiculite containing Al-interlayers is very common in solis, particularly acid soils. Viewed in the light of soil clay minerology, it would be required to investigate the properties of their original minerals. For the latter purpose, the Al-interlayer has been removed prior to the Mg-glycerol,K-saturation and heating tests for identification of montmorillonite and vermiculite. Its removal has been accomplished in sevsral ways; KOH plus KCl (1), NH₄F, KCl plus HCl (2), Na-citrate (3),400C de hydroxylation-NaOH (4) dissolution. Although these methods are effective for the removal of Al-interlayers, they seem drastically to affect the minerals or are time-consuming. Inthe course of the study of hydroxy-Al interlaid complexes of expanding 2:1 layer lattice clay minerals, the authors have noticed the difference between the (001) spacings of hydroxy-Al complexes of montmorillonite and vermiculite; the former exhibited the 20 A basal spacing at room temperature against the 14 A spacing of the latter. This difference might be useful for differentiating montnmorillonite-chlorite intergrades in soils.     

硒、钴单施和配施对苜蓿生长及产量的效应研究

为探讨硒、钴在提高苜蓿生长影响,在河南省沿黄滩区,开展了硒、钴单施和配施下对紫花苜蓿生长以及产量和品质影响研究。结果表明,硒、钴单施和配合基施均能够显著提高苜蓿从现蕾到开花期的净光合能力,降低呼吸消耗,提高单位叶面积干物质的生产速率,有利于苜蓿花前青干草生产和果实发育;其中,以硒570 g/hm2、钴762g/hm2配施下效果显著,青干草增产8.06%,种子千粒重可提高12.85%。单施钴和硒钴配施还能促进0—20 cm耕层苜蓿根瘤菌的生长和积累,增强苜蓿的固氮能力。说明硒钴合理基施对苜蓿青干草和优质种子生产具有很好的应用效果。     

Separation and analysis of diastereomers and enantiomers of cypermethrin and cyfluthrin by gas chromatography

Synthetic pyrethroid (SP) insecticides are of environmental significance because of their high aquatic toxicity. Due to their chirality, SP compounds contain multiple diastereomers and enantiomers. However, due to great structural similarities and lack of isomer standards, gas chromatographic (GC) analysis of SP diastereomers or enantiomers is poorly developed. In this study, we used a HP-5 column to separate the diastereomers and a beta-cyclodextrin-based enantioselective column (BGB-172) to separate the enantiomers of cypermethrin (CP) and cyfluthrin (CF). Resolved peaks were identified by comparing chromatograms of isomer-enriched CP products. Diastereomers of both CP and CF were separated on the HP-5 column. On the BGB-172 column, enantiomers of all cis diastereomers were separated, while those of trans diastereomers were not separated. The elution order appears to be regulated by configuration, a finding which may allow peak identification in the absence of isomer standards. When coupled with electron capture detection, the developed methods had low detection limits and may be used for analysis of SP diastereomers and enantiomers in environmental samples.     

铁铝氧化物和高岭石对转化酶的吸附及活性的影响

Experiments were conducted to study the influences of synthetic bayerite, non-crystalline aluminum oxide (N-AlOH), goethite, non-crystalline iron oxide (N-FeOH) and kaolinite on the adsorption, activity, kinetics and thermal stability of invertase. Adsorption of invertase on iron, aluminum oxides fitted Langmuir equation. The amount of invertase held on the minerals followed the sequence kaolinite > goethite > N-AlOH > bayerite > N-FeOH. No correlation was found between enzyme adsorption and the specific surface area of minerals examined. The differences in the surface structure of minerals and the arrangement of enzymatic molecules on mineral surfaces led to the different capacities of minerals for enzyme adsorption. The adsorption of invertase on bayerite, N-AlOH, goethite, N-FeOH and kaolinite was differently affected by pH. The order for the activity of invertase adsorbed on minerals was N-FeOH > N-AlOH > bayerite > reak goethite > kaolinite. The inhibition effect of minerals on enzyme activity was kaolinite > crystalline oxides > non-crystalline oxides. The pH optimum of iron oxide- and aluminum oxide-invertase complexes was similar to that of free enzyme (pH 4.0), whereas the pH optimum of kaolinite-invertase complex was one pH unit higher than that of free enzyme. The affinity to substrate and the maximum reaction velocity as well as the thermal stability of combined invertase were lower than those of the free enzyme.     

河道堤防滩地的水土流失及其防治

平原地区河道堤防滩地的水土流失,直接淤积河床,影响行洪安全。堤防滩地的水土流失是自然因素和人为因素共同作用的结果,以新修堤防的水土流失最为严重,对其防治须实行工程措施、植物措施和人为预防相结合。     

Effects of residues of lime and phosphorus fertilizer on cadmium uptake and yield of potatoes and carrots

Potatoes (Solarium tuberosum L.) and carrots (Daucus carota L.) were grown in the field on Tasmanian ferrosols (humic eutrudox) which had been limed either 2, 3, or 5 years earlier, and where tuber cadmium (Cd) concentrations in potatoes grown a few months after the liming had shown no lime response. In the current crops lime decreased potato tuber Cd by about 30% and carrot root Cd by about 50%. We attributed the decrease to more even and deeper mixing of the lime with the soil by the harvest of the first potatoes. Phosphorus (P) fertilizer residues from the earlier potato crops did not significantly affect tuber or root Cd, but there was a positive effect at 1 site where some high Cd P fertilizer had earlier been used. Neither lime nor P fertilizer residues affected potato or carrot yields. Analysis at one site of potato tubers from the upper part of the soil ridges showed that they had slightly higher Cd concentrations than did deeper tubers near the fertilizer band, whether P fertilizer was in the band or not. This suggests that either the Cd in the fertilizer band was relatively unimportant as a Cd source for the current crop, or that Cd was redistributed within the plant during the season, or both. Liming may be a suitable medium to long‐term strategy for decreasing Cd uptake by root crops, but site to site and seasonal variation can still be great, and knowledge of other major influences is needed for assurance of produce quality. Our observations need to be extended to sites which gives rise to higher Cd concentrations in agricultural produce, and to other soil types. Potato common scab was severe in the limed plots at one site. However, this site had grown 3 potato crops in 5 years, which probably exacerbated the disease. Potato processors in Tasmania demand a minimum of 5 years between successive crops which should slow any build up of scab due to liming, but more work on possible interactions between lime and rotation length on scab incidence is needed before liming can be recommended as a Cd control measure for potatoes.