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开发建设项目土壤流失量预测方法初探 总被引：17，自引：4，他引：17
开发建设项目土壤流失量预测需要分析的内容有 :原生土壤流失量和土壤容许流失量 ,土壤流失的因子、类型和方式 ,建设项目引发土壤流失的因素和流失分区 ,预测时段和可能造成的土壤流失量。在水力侵蚀流失量预测方法中 ,USLE模型、毗邻项目类比、项目建设前后侵蚀强度类比、典型调查推算法是基本的方法 相似文献
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以北方某煤矿兼并重组项目为例,介绍了合理确定预测单元、预测时段、原地貌和扰动后地貌土壤侵蚀模数的方法。预测过程中首先利用公式求得原地貌土壤流失量、扰动后地貌土壤流失量,求差得生产建设项目新增土壤流失量,再通过对各单元和各时段新增土壤流失量的分析,确定防治和监测的重点防治区和防治时段。 相似文献
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谈开发建设项目扰动面土壤流失量的预测 总被引：3，自引：0，他引：3
介绍了预测土壤流失量的几种常用方法 ,并对每种方法的适用性进行了讨论 ;深入分析了影响土壤侵蚀的各种因素 ,引入加速侵蚀倍率的概念 ,消除了降雨、坡长、土壤类型因素的影响 ;提出了开发建设项目扰动面土壤流失量的计算关系式。 相似文献
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邵学栋 《水土保持应用技术》2007,(6):9-10
生产类开发建设项目扰动面积随时间逐渐变化,扰动面积变化的时间分割单位越小,逐块逐时段累加计算的土壤流失量才越准确,当时间分割单位最小时,土壤流失量才最接近实际。据此,推导出了生产类项目土壤流失量预测公式,采用此公式进行了实例计算。 相似文献
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为比较类比分析法和《生产建设项目土壤流失量测算导则》(SL 773—2018)(以下简称《导则》)测算法土壤流失量预测结果的准确性，以浙江省永嘉抽水蓄能电站为例，分别采用类比分析法和《导则》测算法对工程土壤流失量进行预测，并对预测结果进行对比。结果表明，《导则》测算法得到的土壤流失量远小于类比分析法的；《导则》测算法虽不如类比分析法方便快捷，但可根据下垫面扰动形态、扰动程度及上方有无来水等多重因素区别考虑各计算单元的流失量，计算结果相对更加准确，更接近工程实际情况。同时，基于水电工程可行性研究报告的深度，建议水电工程水土流失分析与预测可在可研阶段根据《导则》开展。 相似文献
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本文以泉州南安市再生石智能制造产线项目为例，分别采用《生产建设项目土壤流失量测算导则》（以下简称“导则”）和传统类比法对其土壤流失量进行预测和比较分析，结果表明：无论采用哪种测算方法，主体工程区均是项目区土壤流失的主要区域，施工期（含施工准备期）均是项目区土壤流失的主要集中时段；《导则》法在测算土壤流失量时更能反映扰动区域的实际情况，可信度高。 相似文献
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开发建设项目土壤流失预测是编制水土保持方案的前提，预测的内容是否全面，方法是否科学，直接关系到预测结果的客观性和准确性，本以两个水电站工程建设为例，分别就应用数学模型法与类比法对水电工程建设中的土壤流失进行预测，详细论述了两种预测方法的主要内容、方法、步骤，探讨了该类项目土壤流失预测所需的基础资料和预测方法的选择。 相似文献
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A comparative-ecological approach for studying the general regularities of soil ecology on the basis of geoinformation systems
is suggested. It has been applied to analyze the distribution of Al-Fe-humus horizons. The quantitative climatic parameters
of soils with Al-Fe-humus horizons have been estimated, and the relationships between them have been established. The applicability
of this approach for assessing the general regularities of soil ecology is shown. 相似文献
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The analysis in this paper is directed at comparing the relative effectiveness of meeting the objectives outlined in the recently passed Clean Air Act Amendments of 1990 through taxation and through regulation. The analytical vehicle used in the analysis consists of a computable general equilibrium model composed of 12 producing sectors, 13 consuming sectors, 6 household categories classified by income, a foreign sector and a government. We find first that, irrespective of what type of strategy is followed, both output and consumption decline. Hence, there is an identifiable and quantifiable tradeoff between economic activity (economic growth) and the quality of the environment. Beyond this, the aggregate loss in production and economic welfare (measured by consumption expenditures and utility) is less under a policy which stresses reliance on alternative fuels than through one that requires the installation of pollution abatement devices. 相似文献
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随着多媒体技术的发展,多媒体技术对教育改革起了很大的推进作用。本文通过在学生中对多媒体课件教学效果的调查,从多媒体教学课件在教学中的作用和地位、制作的过程以及使用者的出发点等方面,对影响到多媒体教学效果的因素进行了分析并提出了自己的解决方法。 相似文献
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跟踪学科前沿，引导学科发展——《农业工程学报》的发展探索 总被引：1，自引：1，他引：1
论述了《农业工程学报》跟踪农业工程学科发展的成功经验，详细分析了未来《农业工程学报》跟踪学科各个专业的报道方向。指出随着学科的发展及时调整学术期刊的报道方向是科技学术期刊的任务和职责，是使期刊保证及时反映相关学科的发展，保持在学科发展中应有的促进作用，在众多期刊的竞争中立于不败之地的保证。在充分分析中国学术期刊面临的形势和问题、机遇与挑战的基础上，提出了学术期刊如何规避不利因素等应对策略，为中国科技学术期刊的发展提供参考。 相似文献
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《农业生物技术学报》2012,(4):435
生物钟在动物植物生理调节中都发挥着重要的作用,但是目前对于其调节机制的了解仍然十分有限。在植物中存在白昼和夜晚的振荡器,这些振荡器包含了拟南芥中已经发现的一些相关的生物钟基因。目前的模型认为白昼振荡器相关基因 相似文献
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The objects of the study are lime-pine and pine-lime park communities of different age at the Arkhangelsk Estate situated near Moscow. In this research, we study spatial variability of the soil properties depending on the type of studied soil cover parcels and with regard to areas under the crowns and near the trunks. The article shows the influence of the grass cover parcel structure on the properties of the soil. The humidity, the content of carbon and nitrogen, and basal and substrate-induced soil respiration are higher in the 120-year-old pine forest stand than in the 80-year-old one. This is explained by the fact that with the increasing age of the pine phytocenoses, we can observe an increase in diversity of species composition, complication of volumetric-spatial structure due to the overgrowth of undergrowth and understory, changes in the volume of the crown, and dying out of old trees. 相似文献
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The composition of the organic matter of the forest Phaeozem soil of Kostroma oblast, which is unusual in its genesis, was investigated by the method of physical fractionation. The Phaeozems were formed in an automorphic position on loamy sediments of Triasic age. The carbon distribution in fractions of organic substance (OS) is the evidence of the hydromorphic nature of the OS origin. A hypothesis about the cause of the formation of the modern organic profile of the soil during evolution is discussed. 相似文献
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Use of the enantiomeric composition for the assessment of the authenticity of fruit beverages 总被引：1，自引：0，他引：1
Ruiz del Castillo ML Caja MM Herraiz M 《Journal of agricultural and food chemistry》2003,51(5):1284-1288
Enantiomeric compositions of chiral terpenes in commercial fruit beverages were examined by solid phase microextraction-gas chromatography (SPME-GC). Optimization of the method was accomplished on the basis of some parameters involved in the extraction, such as heating temperature and extraction time, that provided the highest peak areas, 60 degrees C and 2 min being the optimal values. With the proposed method relative standard deviation (RSD) values from three replicates ranging from 2 to 12% were obtained. The enantiomeric distribution of some terpenes remained constant, whereas other terpenes (linalool, terpinen-4-ol, and alpha-terpineol) exhibited a considerable variation among samples. This can be indicative of the eventual addition of aromas to some fruit beverages. 相似文献