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1.
我国东中西部水土保持发展战略 总被引:1,自引:0,他引:1
根据我国不同地区的自然条件、经济社会发展水平和水土保持生态建设现状,提出“十一五”期间水土保持工作应采取的相应思路和对策。东部地区大力控制开发建设造成的水土流失,实施更高层次的综合治理。中部地区围绕农业生产大局,改善粮食主产区的生产条件,促进农业生产结构调整。西部地区作为我国水土保持生态建设的主战场,立足于国家生态安全,建设东、中部地区的生态屏障。建议“十一五”期间在黄土高原区、长江中上游区、西南岩溶地区、东北黑土区、京津风沙源区、北方沙化草原区,以及太行山、大别山、沂蒙山等革命老区实施7大重点治理工程。 相似文献
2.
现代农业与生态节水的技术创新与未来研究重点 总被引:48,自引:26,他引:48
指出了我国农业与生态节水技术研究领域在试验仪器设备条件、节水灌溉技术与设备研发、精准灌溉和灌溉系统的自动控制、非常规水资源利用与区域农业水资源配置等方面存在的问题及与国际水平的差距,分析了现代农业与生态节水技术研究中在地面灌溉、喷微灌、节水机具、节水材料与制剂、污水灌溉利用、渠道防渗与水量调配、精准灌溉等方面的发展态势,提出了我国农业与生态节水技术创新的总体目标,提出了我国农业与生态节水技术创新的几个重大研究课题,论述了我国农业与生态节水技术创新的保障条件建设内容. 相似文献
3.
姜德文 《中国水土保持科学》2007,5(2):107-109
为落实树立科学发展观、建设资源节约型社会和环境友好型社会的要求,开发建设项目水土保持方案审批已成为项目核准的必备要件,并正在向选优审批转变。开展水土保持损益分析就是为优化审批水土保持方案提供科学依据。其中开发建设项目水土流失影响度是其核心内容,将开发建设项目的影响时间、扰动后的侵蚀强度、影响范围、可恢复程度和生产运行期影响5个主导因子拟合为一个综合评价模型定量计算,分析开发建设项目对水土流失的影响,并以水土流失影响度为标准,客观评价开发建设项目,为政府行政决策和宏观调节提供科学支撑。 相似文献
4.
Sediment deposition is one of the most significant processes in small watersheds characterized by gentle long hillslopes in the black soil(Mollisol)region of Northeast China, as indicated by severe ephemeral gully and gully erosion on hillslopes and very low sediment concentrations in river systems.Few reviews have been conducted to summarize the related research in this region. The objectives of this review were to identify the potential factors influencing sediment deposition, review related s... 相似文献
5.
长期集约化耕作导致中国设施土壤重金属累积和面源污染风险增加的状况已引起广泛关注。该研究总结了中国设施土壤重金属累积状况及其来源,发现长期盲目投入肥料及农药是引发设施菜田土壤重金属累积问题的主要原因。目前,设施土壤重金属累积呈现出广泛性和中轻度污染特征,其中镉是主要的污染元素。遵循面源污染治理中“源头预控-过程阻断-末端修复”原则,基于国内外文献综述,该文总结归纳出适用于设施土壤重金属累积特征与污染的联合阻控技术及作用机制。首先在灌溉和肥药投入等源头环节减少重金属输入;其次在作物种植过程中,通过选用重金属低积累特性的蔬菜种类或品种,结合水肥一体化施用大分子有机水溶性肥料或叶面喷施具有阻控重金属作用的营养型阻控剂,抑制作物吸收重金属;最后在末端修复环节,利用具有多元功能的土壤改良剂或微生物菌剂进行土壤钝化修复,或采用具有超重金属富集能力且能提高设施土壤生物多样性的植物作为填闲作物,实现生物修复的目标。该联合阻控技术的原则在于协同考虑污染防治、土壤改良、减肥增效等农学和环境目标,集成土壤修复与改良、水肥一体化、填闲作物栽培等技术,并兼顾设施土壤重金属污染修复工程所面临的投入品成本较高、经济效益不明显、缺失可持续改良导致效果不稳定等问题,优推能够钝化重金属并改良土壤的多功能土壤改良剂以及具有阻控重金属吸收、提高作物抗逆性的多功能有机水溶性肥料。上述措施能解决设施土壤普遍存在的重金属累积问题,提升土壤的安全生产能力,可为设施农业可持续发展提供更有效的技术支撑。 相似文献
6.
为评价北京山区多年来小流域综合治理的水土保持效果,也为以后小流域治理和植被重建提供理论支撑,以房山区蒲洼小流域为研究地,采用典型样地调查、野外抗冲性实验和室内样品处理的方法,对比分析不同水土保持措施的土壤物理性质、土壤质地和抗冲性.结果表明:随着土层加深,各类措施下土壤密度均呈现增大趋势,总孔隙度和毛管孔隙度呈现减小趋势,而非毛管孔隙度没有明显规律.不同水土保持措施下,土壤密度、总孔隙度和毛管孔隙度均有改善(侧柏林除外),改善程度由好到差依次为:辽东栎次生林>油松落叶松混交林>石坎梯田>油松林>落叶松林>灌丛;各类措施下土壤颗粒均以细、中粉粒为最多,分形维数显示各类水保措施土壤通透性均较为良好;相比荒地,各类措施下土壤冲刷量显著减小,径流时间延长,冲刷量依次为油松落叶松混交林(0.82 kg/cm3)<侧柏林(1.14 kg/cm3)<落叶松林(1.30 kg/cm3)<辽东栎次生林(3.91 kg/cm3)<油松林(5.96 kg/cm3)<荆条灌丛(10.88 kg/cm3),延缓径流冲刷时间由大到小依次为:辽东栎次生林(55.65 s/m)>油松落叶松混交林(46.82 s/m)>落叶松(28.19 s/m)>荆条灌丛(22.39s/m)>侧柏林(17.48 s/m)>油松林(16.94 s/m).土壤抗冲性与细、中粉粒体积分数(正相关)、非毛管孔隙度呈显著(负相关)关系最为密切,由此推出大根径的根系穿插形成的非毛管孔隙对土壤抗冲性是负效应.综上,油松落叶松林混交林提升土壤蓄水持水性能、土壤抗冲性均显示出很大的优势;石坎梯田效果也较好,是小流域治理应首先考虑的2类措施. 相似文献
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8.
Natural mineral dust has manifold environmental effects reaching from fertilizing aquatic and terrestrial ecosystems to affecting the earth's radiation balance and thus impacting on climate. The Sahara is considered the largest source of natural mineral dust on the globe, so much research attention has been paid to source identification, dust mobilization, transport, and effects in the sink areas. This paper gives a review of the research results concerning these topics emphasizing soil‐science‐related aspects of the last 20 y and the identification of knowledge gaps. 相似文献
9.
W. R. S. Critchley C. Reij T. J. Willcocks 《Land Degradation \u0026amp; Development》1994,5(4):293-314
After half a century of failed soil and water conservation projects in tropical developing countries, technical specialists and policy makers are reconsidering their strategy. It is increasingly recognised that the land users have valuable environmental knowledge themselves. This review explores two hypotheses: first, that much can be learned from previously ignored indigenous soil and water conservation (ISWC) practices; second, that ISWC can often act as a suitable starting point for the development of technologies and programmes. However, information on ISWC is patchy and scattered. Many ancient, derelict systems are better described than traditions which still persist today. ISWC has been most commonly developed under dry and marginal conditions, and/or on steep hillsides. Sustained population pressure has often tended to stimulate ISWC. There is a need for more incorporation of ISWC into resource conservation programmes: many projects have ignored local traditions to their detriment. It is widely agreed that further study and research on ISWC is required and justified as a logical starting point towards developing adoptable and sustainable soil and water conservation systems for small-scale farmers. 相似文献
10.
《国际水土保持研究(英文)》2022,10(1):149-160
Accelerated soil erosion is a major threat to soil, and there are great variations in the rate of soil erosion over time due to natural and human-induced factors. The temperate forest zone of Russia is characterized by complex stages of land-use history (i.e. active urbanization, agricultural development, land abandonment, etc.). We have for the first time estimated the rates of soil erosion by the WaTEM/SEDEM model (rainfall erosion) and by a regional model (snowmelt erosion) over the past 250 years (from 1780 to 2019) for a 100-km2 study site in the Moscow region of Russia. The calculations were made on the basis of a detailed historical reconstruction of the following factors: the location of the arable land, crop rotation, the rain erosivity factor, and the maximum snow water equivalent. The area of arable land has decreased more than 3.5-fold over the past 250 years. At the end of the 20th century, the rates of gross erosion had declined more than 5.5-fold (from 28 × 103 to 5 × 103 t?ha?1?yr?1) in comparison with the end of the 18th century. Changes in the boundaries of arable land and also the relief features had led to a significant intra-slope accumulation of sediments. As a result of sediment redeposition within the arable land, the variation in net soil erosion was significantly lower than the variation in gross soil erosion. The changes in arable land area and in crop composition are the factors that have to the greatest extent determined the changes in soil erosion in this territory. 相似文献
11.
王治国 《中国水土保持科学》2007,5(6):87-92
以小流域为单元实施山、水、田、林、路、渠综合治理的理论与技术体系是在我国水土保持长期生产实践和科学研究中形成的具有中国特色的水土保持学科体系。通过川陕"长治工程"中期评估考察,分析"长治工程"小流域综合治理的特色与创新,并据此讨论我国水土保持学科的性质与定位。水土保持学科无论从法律地位还是学术地位,均应归属于资源保护与利用的范畴,与环境保护和生态学科的本质区别在于,水土保持更具有突出的生产功能。现阶段水土保持学科仍应首先赋予其防治水土流失,治理江河,提高农业生产综合能力,发展农村经济,改善农村基础设施及农民生活质量的内涵,并努力使之与农村生态建设结合,以不断深化和丰富其内涵,同时应在开发建设项目水土保持、饮用水水源地水土保持等方面拓展其学科外延。 相似文献
12.
无人机遥感技术在生产建设项目水土保持监测中的应用——以鄂北水资源配置工程为例 总被引:2,自引:0,他引:2
无人机遥感技术在水土保持监测工作中的应用尚未形成统一有效的方法与标准,针对这一问题,笔者以鄂北地区水资源配置工程为例,从遥感基础数据获取、基本监测信息提取、监测信息应用3个方面,开展水土保持监测实例分析.首先,针对案例工程的几个典型区,在航拍的基础上,利用Agisoft Photoscan Professional软件处理原始影像,获取各区域的DOM和DEM成果,其水平精度分别可达0.05和0.2m.然后,基于DOM和DEM提取监测对象的土地利用类型、位置、面积、体积等信息,构建三维虚拟模型.结果表明计算机自动识别更加快速,但存在将监测对象的阴影、苫盖误判为植被的问题.最后,将提取的信息逐一应用于案例工程的水土保持监测工作,直接获取各典型区扰动土地面积、弃渣体积、苫盖与否、苫盖面积等监测结果.无人机监测结果与运用传统方法监测的结果对比表明,2种方法的监测结果均满足相关技术要求,但无人机监测效率是传统人工监测效率的3~5倍.成果可为无人机遥感技术在水土保持监测中的应用提供有效的方法借鉴. 相似文献
13.
结合苏里格3个气田开发工程的实际情况,对苏里格气田开发工程的组成、征占地面积、水土流失防治措施分别进行分析与评价,并通过经验总结,提出目前生产建设项目水土保持工作中存在的问题和不足。结果表明:1)气田工程项目组成较为复杂,占地以临时占地为主,占整个项目占地的75%左右;2)在水土流失防治分区中,以管网区与道路区所占比例最大,占整个项目占地的90%左右,同时也是整个项目中产生水土流失的重要部位,占整个项目水土流失量的90%左右,是水土流失防治与监测的重点部位。根据调查提出目前水土流失防治措施中存在的问题,并提出建设性意见和具体思路。 相似文献
14.
How does the Hedley sequential phosphorus fractionation reflect impacts of land use and management on soil phosphorus: A review 总被引:7,自引:0,他引:7
The Hedley sequential‐phosphorus (P)‐fractionation method has been used in many countries to study the effects of land‐use and management systems on soil P. Many data sets have been obtained but collectively never have been considered or to goal topic reviewed. Therefore, the objectives of this review were to compile and systematically evaluate these data. The data generated over many years were grouped into temperate, and subtropical and tropical soils of different land use and duration of soil‐management studies. In natural ecosystems, vegetation types and composition and percent of vegetation covers substantially affected all P fractions with pronounced impacts on the labile and moderately labile P. In short‐term studies (≤ 10 y), changes in the labile and moderately labile inorganic P (Pi) fractions were detected when more P (e.g., by factor 5) was applied than commonly recommended for agricultural crops. However, without P application the changes in all P fractions were subtle in temperate soils, but declines were significant in labile and moderately labile P in subtropical and tropical soils. In both temperate and tropical climates, medium (10–25 y) and long‐term (>25 y) cultivation without P application depleted all P fractions, whereas most of P fractions increased with continuous P application, regardless of the amount and source of P. Synthesis of data resulted in multiple‐regression functions which described differences in labile and moderately labile P fractions as function of differences in amount of P application and duration of the experiments. Moreover, the correlation analysis also showed strong association among most of the P fractions. Current limitations in data interpretation of Hedley fractionation can be overcome by the application of 31P nuclear–magnetic resonance (NMR) and X‐ray absorption near‐edge fine‐structure (XANES) spectroscopy. 相似文献
15.
I. Emadodin S. Reiss A. V. Mitusov H. R. Bork 《Land Degradation \u0026amp; Development》2009,20(5):551-561
Soil degradation is a serious problem and an important environmental issue in many ecosystems. Without integrative, interdisciplinary and historical approaches, understanding the effects of long‐term soil degradation is difficult. According to this idea it is hypothesized that in order to study long‐term natural and human‐induced soil degradation, it is necessary to use interdisciplinary and multidisciplinary approaches with respect to temporal and spatial landscape changes. The results of the investigation of colluvial sediments and soils in research area in Schleswig‐Holstein (Germany) with a high resolution in space and time—using the four‐dimensional landscape analysis—indicated the temporal and spatial variation of soils and sediments from the Mesolithic until Modern times. Intensive soil degradation occurred as a result of the land clearance and agricultural land use in the investigation areas since the Neolithic time. The general results of this investigation show that the use of an interdisciplinary and multidisciplinary approach with pedological and geomorphological perspectives for different times and places can help to reconstruct the long‐term natural and human‐induced soil degradation. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
16.
许炯心 《中国水土保持科学》2009,7(4):7-13
流域系统可以分为坡面系统和沟道-河道系统2大单元,可以分别建立泥沙收支平衡关系。结果表明:1)实施水土保持措施以后,无定河流域系统泥沙收支平衡中各变量均随时间而变化。沟道-河道系统泥沙输移比发生了极显著的减小趋势,泥沙存储量发生了显著的增大趋势,流域产沙量的变化发生了较显著的减小趋势,坡面净侵蚀量有所减少,但变化趋势不显著。2)对于不同的泥沙收支平衡变量的变化而言,水土保持措施变化和降雨变化的贡献率是不同的;对坡面净侵蚀量的变化而言,汛期降雨的变化起着决定性的作用,贡献率高达90.82%,坡面水土保持措施的贡献率仅为9.18%;对沟道河道系统泥沙存储量的变化而言,淤地坝拦沙的变化起着决定性的作用,贡献率高达76.16%,汛期降雨变化的贡献率仅为23.81%;对流域产沙量的变化而言,汛期降雨和水土保持措施的变化都起着重要作用,前者贡献率为57.84%,后者贡献率为42.16%。3)对沟道-河道系统泥沙输移比RSDRc的变化而言,淤地坝拦沙的变化起着决定性的作用,贡献率高达87.27%,汛期降雨变化的贡献率仅为12.73%。 相似文献
17.
贫困与生态环境之间的关系是多维、复杂、因地而异的,需要翔实数据与典型案例的支撑,更需要全新的视角.传统研究过于强调某一主体的作用,忽略了不同主体综合作用的结果,尤其是忽视了不同主体之间相互作用过程,因此,还不足以全面理解贫困与生态环境之间的复杂关系.以福建长汀县为典型区域,运用利益主体分析框架探讨政府、民众、企业、非政府组织(NGOs)、国际组织等不同利益主体在水土保持生态建设过程中的作用机制.研究结果有助于充分理解不同利益主体的作用机制,并为同类区域制定扶贫战略与资源环境保护政策提供借鉴. 相似文献
18.
Bijender SINGH Ines BOUKHRIS PRAGYA Vinod KUMAR Ajar Nath YADAV Ameny FARHAT-KHEMAKHEM Anil KUMAR Davender SINGH Monia BLIBECH Hichem CHOUAYEKH Othman A. ALGHAMDI 《土壤圈》2020,30(3):295-313
Phytases belong to the class of phosphohydrolases that begin the step-wise hydrolysis of phosphates from phytates. Phytates are a derivative of myo-inositol, which is the primary storage form of organic phosphorus in plant cells. Phytase has been used globally to diminish phosphorus pollution and to enhance nutrition in monogastrics. In this review, the classification, sources, and diversity of microbial phytases, and their practical applications, as well as supplementation of the soil with transgenic and wild types of microbial strains, which can release phytase to enhance phosphorus availability for plant uptake and reduce the need for fertilizers, are discussed. The overexpressed microbial phytases in transgenic plants enhance the growth capacity of co-cultivated plants and can therefore be employed in agricultural and biotechnological practices, such as intercropping. The introduction of phytases into the soil for improved plant growth and enhanced crop yield can be accomplished without extra cost. A diverse group of photoautotrophic microalgae can synthesize phytase and will likely be useful in many human food and animal industries. 相似文献
19.
基于能值理论的水土保持生态效应评价——以山西省长治市为例 总被引:1,自引:0,他引:1
运用能值理论分析方法,选取2004-2014年的统计数据,对长治市水土流失治理生态经济系统的投入产出能值及主要能值指标进行分析.研究表明:系统能值投入波动较大,整体呈增加趋势,最低值为2008年的3.91×1021sej,最高值为2011年的4.33 ×1021 sej;系统总能值产出呈现整体增加、局部时间段下降趋势,最低值为2010年的5.95 ×1021sej,最高值为2014年的7.62 ×1021sej,其中2大主导产业中畜牧业整体呈增加趋势、农业中蔬菜产量不断增加都说明水土保持措施取得了一定成效;主要能值指标中,净能值产出率均>1、可持续发展指数1<ESI< 10,说明长治市水土保持措施的合理性与可持续性.能值理论分析表明,长治市水土流失治理生态经济系统的综合水平总体上呈现上升趋势,系统可持续发展状态良好,生态和经济向着平衡方向发展. 相似文献
20.
Daniela Sauer Herbert Sponagel Michael Sommer Luise Giani Reinhold Jahn Karl Stahr 《植物养料与土壤学杂志》2007,170(5):581-597
The Podzol has been elected “Soil of the year 2007” in Germany. This article reviews the present knowledge on the development, functions, and threats of Podzols. The main theories on mobilization and transport of organic matter, Fe, Al, and Si are (1) metal‐organic migration, (2) metal reduction, and (3) inorganic sol migration. Immobilization theories include precipitation or polymerization due to increasing pH/abundance of base cations with depth, mechanical filtering in soil pores, oxidation of metal‐organic complexes, biodegradation of the organic part, decreasing C‐to‐metal ratios during translocation, adsorption to soil particles, and flocculation at the point of zero charge. Podzolization is discussed also on the catena scale, where vertical and lateral translocation processes (across pedon boundaries) need to be considered to understand Podzol patterns in landscapes. Chronosequence studies show that incipient podzolization usually becomes visible between 100 and 500 y and mature Podzols develop in 1,000–6,000 y. The occurrence of Podzols worldwide is concentrated mainly on the boreal zone and mountain regions within the humid temperate zone. Smaller Podzol areas are found in some perhumid tropical and subtropical regions. In Germany, Podzols occur in the Alps, in the glaciofluvial valleys and heathlands of N Germany, and in the mountain ranges. They fulfil several ecological functions, especially for groundwater recharge. Main threats for these mostly sandy soils are wind erosion and surface mining of sand. Two pedons which were chosen to represent the “Soil of the year 2007” are presented. Finally, some conclusions about podzolization processes are drawn, which may explain the diverse observations reported in the literature. 相似文献