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基于景观生态学原理的生态清洁小流域规划与设计——以怀柔区前喇叭沟小流域为例 总被引:1,自引:1,他引:0
生态清洁小流域建设是北京市生态建设的重要组成部分,在生态清洁小流域综合治理设计中引入景观生态理念,是新时期生态建设与保护的要求。以景观生态学原理为基础,分析了生态清洁小流域建设中规划与设计的原则、方法、目标及步骤。以北京市怀柔区前喇叭沟小流域为例,探讨了景观生态理论在生态清洁小流域建设中的应用,旨在依据小流域不同景观功能区特征协调资源利用与环境保护的关系,为生态清洁小流域建设达到小流域景观格局与其功能的和谐统一提供参考。 相似文献
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北京山区小流域生态清洁程度分级研究 总被引:1,自引:0,他引:1
小流域生态清洁程度分级是制定小流域治理规划和措施的基础,有助于提高治理的针对性和治理效益。结合北京山区实际情况确定了用于评价小流域是否生态清洁的8项关键指标,并在对指标数据进行详细分析的基础上确定了具体的评价标准,进而根据8项关键指标达标的情况,将小流域分为生态清洁小流域和非生态清洁小流域,揭示了小流域建设中存在的薄弱部分。同时,采用相对评价的方法开展了小流域生态清洁程度的分级研究。根据11项评价指标的综合得分,将小流域按生态清洁程度由高到低划分为"生态清洁1级"至"非生态清洁5级"10个级别。 相似文献
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北京市山区小流域主沟道水文地貌调查与分级 总被引:1,自引:0,他引:1
以北京山区小流域主沟道为研究对象,研究小流域主沟道水文地貌调查要素及分级方法.以沟道河床、河岸及缓冲带、河滩地、河流整体为主要调查与评价因子,将北京山区小流域主沟道水文地貌划分为极好(Ⅰ级)、好(Ⅱ级)、中等(Ⅲ级)、差(Ⅳ级)、极差(Ⅴ级)5个等级,并对开展水文地貌修复工程的7条小流域和全市567小流域主沟道进行分级,结果表明:全市山区567条小流域,调查主沟道总长度为4 258 km,属于Ⅰ级、Ⅱ级、Ⅲ级、Ⅳ级和Ⅴ级的沟段长度比例分别为64.85%、14.02%、9.56%、8.76%和2.81%,其中Ⅱ级及以上的沟段长度占到总长的78.87%.研究成果将为北京市及全国河流水文地貌生态修复、生态清洁小流域建设提供重要参考. 相似文献
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分布式水文模型在小流域综合治理规划中的应用 总被引:1,自引:0,他引:1
密云水库是北京市唯一的地表饮用水源,其上游山区是主要的水源涵养和供给地。位于水库上游北部山区的白马关河是一条直接进入水库的支流,虽然年径流量并不大,但是汛期随降雨径流带出的污染负荷进入密云水库,会对水库水质造成直接影响,弄清该流域降雨径流状况是进行水土流失和污染负荷估算及清洁小流域建设的基础。本研究采用分布式水文模型,对水库上游白马关河小流域内不同降雨频率下的产汇流进行了模拟计算,分析其下垫面特性对降雨径流的影响规律,为白马关河小流域的综合治理规划和非点源污染负荷控制提供参考。 相似文献
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浅谈北京市生态清洁小流域建设规划 总被引:1,自引:0,他引:1
生态清洁小流域建设规划是指导生态清洁小流域建设与管理的依据,目前我国尚无统一的生态清洁小流域建设规划方案编制规范可供遵守。从指导思想、基本原则、主要内容和规划步骤4个方面对北京市生态清洁小流域建设规划编制进行了介绍,提出了规划原则、功能区划分标准、规划措施总体布局及管理和治理措施规划的基本内容,最后对规划的步骤进行了简要的探讨。 相似文献
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结合当前北京市开展的生态清洁小流域建设,尝试利用现有的高分辨率航片,采用基于面向对象的高分辨率影像分类技术和G IS技术来开展生态清洁小流域水土保持现状等本底资料的调查,从而为生态清洁小流域的基础数据库建设、治理措施规划与布局提供基础数据和科学依据。应用实例表明,采用面向对象影像分类技术开展生态清洁小流域现状调查,在方法上、技术上都是可行的,不仅可以提高调查的客观性、准确性和现势性,而且也可以大大提高调查的工作效率,是未来生态清洁小流域调查的可选方法。 相似文献
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Suyundukov Ya. T. Suyundukova M. B. Bezuglova O. S. Khabirov I. K. Khasanova R. F. Semenova I. N. Rafikova Yu. S. Ilbulova G. R. 《Eurasian Soil Science》2022,55(1):27-35
Eurasian Soil Science - The results of the study of the properties of urban soils of the city of Sibay located in the mining region of the Republic of Bashkortostan are presented. A specific... 相似文献
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Kholodov V. A. Farkhodov Y. R. Yaroslavtseva N. V. Ziganshina A. R. Maksimovich S. V. 《Eurasian Soil Science》2022,55(7):998-1004
Eurasian Soil Science - Layers were step-by-step removed from macroaggregates (2–1 mm in diameter) of Protocalcic Chernozems via successive abrasion in a revolving rotator during 5, 10, 15,... 相似文献
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姬松茸多糖提取工艺的优化 总被引:8,自引:0,他引:8
对姬松茸子实体多糖提取的工艺条件中的多糖提取温度、提取时间、浸提液pH值3因子的最优化组合问题进行了定量研究,建立了具有良好预测性能的姬松茸多糖提取条件的模型,并利用回归模型对工艺条件的最优化组合,对各单因子要素的多糖得率及其交互作用进行了探讨。试验表明,当浸提温度为100℃、浸提时间为3h、浸提液pH值为6.3时多糖得率处于较高水平 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(15-16):1631-1646
Abstract Brazil has approximately 30 million hectares of lowland areas, known locally as “Varzea,”; distributed throughout the country. Soils in these areas have the potential to support agricultural production, but very little is known about their fertility. The current experiment was undertaken to characterize the chemical and physical properties of representative “Varzea”; soils collected at 0–20, 20–40, 40–60, and 60–80 cm depth intervals from 23 sites in Goias State of Brazil. Organic matter contents averaged 42 g/kg in the surface 20 cm of soil and should make a significant contribution to overall nutrient availability. Soil pH increased slightly with depth from a mean value of 5.2 in the surface 20 cm of soil to a mean value of 5.4 in the 60–80 cm depth interval. Several soils had exchangeable Al values ≥ 1.0 cmol Al/kg, but soil Al saturation was generally less than the 60% level frequently associated with Al toxicity. However, cereal and legume production could benefit from lime addition in many of these soils. Although base saturation was fairly low in some soils, exchangeable Ca and Mg levels were, in general, adequate throughout the profile. Extractable P levels were adequate in most surface soil samples. Extractable K levels in these soils were generally low, and the application of K fertilizers should be beneficial, especially in conjunction with lime addition. The high clay content “Varzea”; soils of the Brazilian lowlands have some drainage problems but generally exhibit favorable chemical properties for crop production when compared to soils of the well‐drained Cerrados. 相似文献
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Ye. V. Rogozhina N. V. Kostina L. S. Malyukova 《Moscow University Soil Science Bulletin》2011,66(1):32-35
An estimation of potential nitrogen-fixing activity of various soil types under agrophytocenoses of tea, filbert, peach, and
pawpaw which grow in the area of Greater Sochi is given. High indicators of nitrogen fixation activity in the soil in the
course of vegetation were characteristic of agrocenoses of pawpaw, peach, and filbert. The lowest level of nitrogen fixation
was noted in the soil of a tea plantation. A negative correlation dependence of potential nitrogen-fixing activity on the
acidity of the soil solution was established. A study of the seasonal dynamics of the activity of nitrogen fixation of soils
of agrocenoses of the subtropical zone of Russia made it possible to distinguish a less active winter and more active spring-summer-autumn
periods. 相似文献
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淤地坝坝体体积的计算 总被引:3,自引:1,他引:3
对于已确定的淤地坝坝址,坝体的纵断面(即沟道横断面)是一定的。根据实测的沟造横断面,以沟底最低点为坐标原点,沟道一侧的岸壁曲线可用幂函数形式表示之。利用这种幂函数关系,对于坝坡均一的坝体.在设定坝顶宽、坝高和上下游边坡之后,作者推导出沟道一侧坝体体积的计算公式;沟道两侧的坝体体积即为坝体总体积。对于非均一坝坡、设有马道的坝和坝体加高的体积,可将坝体横断面分割为由几个均一坝坡组成的坝体断面,分别计算其体积。这种计算方法的精度,取决于坝址横断面岸壁曲线回归方程与实际岸壁的符合程度。 相似文献