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DISCUSSION ON THE ECOLOGICAL REGULATION AND CONTROL OF CROP PESTS IN AGRICULTURAL ECO-SYSTEM

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DISCUSSION ON THE ECOLOGICAL REGULATION AND CONTROL OF CROP ...

The ⅩⅤth International Plant Protection Congress

作者： ZHAO Hui-yan College of Plant Protection northwest science and {2.nology university for agriculture and forestry yangling 712.00 Shaanxi china

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泥河沟小流域土壤养分的分布与保护

水土保持学报 2002年第3期16卷 86-89页

作者：莫翼翔吴发启杨凌职业技术学院陕西杨凌712100 西北农林科技大学资源环境学院陕西杨凌712100

以淳化县泥河沟流域为对象 ,通过不同时期土壤样品的分析以及径流小区资料的统计 ,得出该流域土壤养分具有明显的空间分布规律 ;从分水岭到沟缘 ,土壤肥力呈衰减趋势 ,沟谷地向沟床呈增大的变化趋势 ,其主要是水土流失的结果。因此 ,进... 详细信息

以淳化县泥河沟流域为对象 ,通过不同时期土壤样品的分析以及径流小区资料的统计 ,得出该流域土壤养分具有明显的空间分布规律 ;从分水岭到沟缘 ,土壤肥力呈衰减趋势 ,沟谷地向沟床呈增大的变化趋势 ,其主要是水土流失的结果。因此 ,进行水土流失综合治理、坡耕地覆膜套种等是保护与恢复土壤肥力的有效途径。

关键词：泥河沟小流域分布保护土壤养分综合治理

Afforestation technique of Xanthoceras sorbifolia Bunge.

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Asian Agricultural Research 2012年第1期4卷 81-84页

作者： XIANG Xiao-qin1, LI Qiao-qin2. LI Zhong-hong1, LIU Guang-zhe3 1. Fuxian County forestry Station of Shaanxi Province, Fuxian County, 72.500, china 2. Qiaobei forestry Bureau, Yan’an 72.500, china 3. College of forestry, northwest agriculture and forestry university, yangling 712.00, china

We conducted the study on afforestation technique of Xanthoceras sorbifolia Bunge. in combination with ecological environment features of Fuxian County in Shaanxi Province. Results show that it is proper to adopt "sunny gentle slope+fish-scale pit+planting on ridges after dipping mud+stumping in autumn" for afforestation of Xanthoceras sorbifolia Bunge. in the Loess Plateau. It is expected that our study can play a significant role in guiding popularization of Xanthoceras sorbifolia Bunge. in the northwest of{2..

关键词： Xanthoceras sorbifolia Bunge. Afforestation techni

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维普期刊数据库

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河溪近自然治理的基本模式与应用界限

水土保持学报 2002年第6期16卷 84-87,91页

作者：高甲荣肖斌牛健植北京林业大学水土保持与荒漠化教育部重点实验室北京100083 西北农林科技大学林学院陕西杨陵712100

河溪系统是流域管理中最基本和最重要的单元。在分析传统河溪治理的基础上,简要地介绍了河溪近自然治理的概念、发展和特征,提出了河溪近自然治理的原则,并对河溪近自然治理的基本模式进行了探讨。

关键词：河溪近自然治理基本模式应用界限

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Y型窄缝挑坎水力特性试验研究

水电能源科学 2011年第3期29卷 81-83页

作者：巩兴晖刘韩生西北农林科技大学水利与建筑工程学院陕西杨凌712100

以斯木塔斯水电站为例,针对原矩形窄缝挑坎不能满足工程需求的问题,提出了一种Y型窄缝挑坎的体型设计方案,通过模型试验分析了不同工况下该体型流速、压强、水舌形态等各项水力特性。结果表明,Y型窄缝挑坎各项水力特性良好,消能效果显著。

关键词： Y型窄缝挑坎消能模型试验水力特性水舌

Relationship Between agriculture and Ecological Deterioration,Restoration and Reconstruction in Loess Plateau Areas of northwest{2.

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Agricultural sciences in china 2002年第1期1卷 114-120页

作者： CHENG Xu( china Agricultural university, Beijing 100094) china Agricultural university Beijing 100094

A comprehensive analysis was conducted on the current situation as well as historic succession processor agriculture and ecological conditions in northwest{2., in particular in the Loess Plateau, by means of a inter-disciplinary approach of ecology, agro-geohistory, and agronomy. It was concluded that the fundamental causes responsible for the ecological deterioration, signed by the poor agro-productivity and serious soil erosion, had been the extensive cropping system by ever-increasing reclamation on semi-drought slope land, where initiated a natural vegetation of brushy grasses with sparse trees, thus suitable only for animal husbandry. Based on an identification of specific actual status of{2., several countermeasures of correctly dealing with the relationship between agricultural development and the ecological restoration and reconstruction were proposed, including to get breakthrough first in the transection area by means of the rational use of resources and the raising of agro-system productivity, to promoting 'water conservancy-type ecological agriculture' through the radical shift of traditional production pattern, and the adoption of a policy of proper degree of grain self-reliance, as well as to construct livestock industry base in northwest{2..

关键词： Loess Plateau Area of northwest china Agricultural ecology

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坡耕地土壤水分入渗影响因素分析

水土保持通报 2003年第1期23卷 16-18,78页

作者：吴发启赵西宁佘雕西北农林科技大学陕西杨凌712100 中国科学院水利部水土保持研究所陕西杨凌712100

利用人工模拟降雨装置对影响坡耕地土壤入渗的诸因素进行了研究。发现坡面产流历时与土壤容重、初始含水率、坡度、降雨强度、耕作管理措施呈负相关;土壤稳渗速率与降雨强度、耕作管理措施呈正相关,与土壤容重、初始含水率、坡度呈负相... 详细信息

利用人工模拟降雨装置对影响坡耕地土壤入渗的诸因素进行了研究。发现坡面产流历时与土壤容重、初始含水率、坡度、降雨强度、耕作管理措施呈负相关;土壤稳渗速率与降雨强度、耕作管理措施呈正相关,与土壤容重、初始含水率、坡度呈负相关。通过综合因素分析可知,影响坡面土壤入渗和产流历时的主要因子为土壤物理性质和耕作管理措施。

关键词：坡耕地土壤水分入渗影响因素分析土壤稳渗速率

THE VOID FRACTION DISTRIBUTION IN TWO-DIMENSIONAL GAS-LIQUID TWO PHASE FLOW USING IMAGE PROCESS METHOD

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Journal of Hydrodynamics 2006年第2期18卷 127-134页

作者： ZHAO Ke-yu CHENG Wen LIAO Wei-li ZHOU Xiao-de College of Water Resource and Architectural Engineering Northwest Agriculture and Forestry University Xi＇an 712100 China Environment Research Institute Xi＇ an University of Technology Xi＇an 710048 China

An image processing method for measuring the instantaneous two-dimensional （2.） local void fraction at high bubble number density was proposed. It was based on computing a correlation between the locally averaged brightness of the bubble plume images and the real void fraction. The method was tested using the 2. distribution of local void fraction from visualized image, where a correlation between the locally averaged brightness and the projection void fraction was derived by introducing an ideal of overlapping probability of the bubble-images under various conditions. This research was used to study the behavior of the bubbly flows with aspect ratio of 1.0,1.5, and 2.0. The present method was applied to the instantaneous measurement. The void fraction for bubble plumes of three different aspect ratios with three different bubble generating flow rates were measured for the clarification of the effect of the bubble on the behavior of the bubbly flows. Dependency of the void fraction on the gas flow rate was measured and compared to other results from the literature. In the range of our experiments, it was observed that not only does an aspect ratio of the tank affect the structure of the plume, but also the gas flow rate in the tank affects the structure of the plume.

关键词： local void fraction gas-liquid two-phase flow,brightness aspect ratio the projection void fraction

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拟南芥基因密码子偏爱性分析

生物化学与生物物理进展 2003年第2期30卷 221-225页

作者：范三红郭蔼光单丽伟胡小平西北农林科技大学

密码子偏爱性对外源基因的表达强度有一定影响 ,特别是编码蛋白质N端 7～ 8个氨基酸残基的密码子 .通过对拟南芥染色体中 2.6 82.7个蛋白质对应的基因密码子进行分析 ,得到了编码氨基酸的 6 1种密码子在拟南芥中的使用频率 ,并与大肠杆... 详细信息

密码子偏爱性对外源基因的表达强度有一定影响 ,特别是编码蛋白质N端 7～ 8个氨基酸残基的密码子 .通过对拟南芥染色体中 2.6 82.7个蛋白质对应的基因密码子进行分析 ,得到了编码氨基酸的 6 1种密码子在拟南芥中的使用频率 ,并与大肠杆菌和哺乳动物进行了比较 ,结果表明三者间的密码子偏爱性有较大差异 .这一分析结果对于动物基因在植物中的表达 ,及植物基因在微生物中的表达具有一定指导意义 .

关键词：拟南芥基因密码子偏爱性植物 XML