Results 31 to 40 of about 447 (144)
Exploration on the Stratification of the Ground Substrate Survey and the Design and Construction of Its Testing Indicator System [PDF]
The ground substrate layer is the main carrier of the material and energy cycle of the earth’s surface. At present, it is essential to have a suitable ground substrate stratification and testing index system for conducting an effective ground substrate ...
Aibing HAO +13 more
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Effects of Tillage Disturbance on Slope Shape and Micro-topographic Features on Typical Sloping Cropland of Southwestern Alpine-canyon Area [PDF]
[Objective] The objective of this study was to investigate the effects of various tillage practices on on slope shape and micro-topographic features on typical sloping croplands of southwestern alpine-canyon area.
LIU Jingyi +8 more
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An Observation on Non-state Higher Education in Russia [PDF]
, 2004 当今俄罗斯私立高等教育的基本特征可以概括为“六多六少” ,即高校数、学生数的地理分布上大都会多 ,小城市少 ;在高校数与校均学生数的比例上 ,高校数多 ,校均学生数少 ;在专业分布上 ,文科生多 ,理工科生少 ;在学习形式上 ,业余制多 ,全日制少 ;在教师结构上 ,兼职多 ,专职少 ;在校舍面积中 ,租用面积多 ,专用面积少。At present, the basic characteristics of Non-state Higher Education in Russia can be ...
杨广云
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Shuitu Baochi Xuebao, 2006 在明确土壤容许流失量概念与意义的基础上，指出了我国东北黑土区现行的土壤容许流失量标准存在的不足。参考国内外土壤容许流失量制定的影响因子，以成土速率、水土流失类型与强度、土层厚度为主要参考指标，并提出以我国现行及未来一定时期内，水土保持实践中可能达到的限制土壤侵蚀的极限，作为确定东北黑土区土壤容许流失量的重要参考指标。综合考虑对黑土区内72条小流域水土保持实践的调查结果，初步确定了东北黑土区主要水土流失类型区土壤容许流失量指标及水土保持治理指标。
范昊明 +5 more
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Shuitu Baochi Xuebao, 2003 利用最新的土地沙漠化遥感监测数据(2000年),研究分析了黑河流域中下游地区的土地沙漠化现状及土地沙漠化发展的原因,并提出了其土地沙漠化防治的具体对策和措施。结果表明,2000年黑河流域中下游地区共有沙漠化土地13508.4km2,土地沙漠化类型包括耕地、草场、砾质沙漠化以及沙丘活化4种,总面积占监测土地面积(114446km2)的11.8%,其中轻度沙漠化土地27.4km2,占沙漠化土地总面积的0.2%,中度沙漠化土地1321.4km2,占9.8%,重度沙漠化土地2274.3km2,占16.8 ...
齐善忠 王涛
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Distribution Characteristics and Source Analysis of Soil Heavy Metals in the Liaoyang—Dandong Region [PDF]
The Liaoyang—Dandong region is an important grain and cash crop production area in Liaoning Province. It is of great significance for monitoring the quality of black soil and studying the migration and transformation of heavy metals in soil to understand
Cang GONG +9 more
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Phosphorus adsorption and desorption characteristics and its response to soil properties of black soil under long-term different fertilization [PDF]
, 2019 editorial reviewedObjective: Fertilizer is generally added to agricultural soil to meet the needs of crop production, but long-term over fertilization changes soil phosphorus (P) pool and soil properties.
Gao, HongJun +7 more
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Shuitu Baochi Xuebao, 2001 在分析我国东北黑土的土壤侵蚀、养分减少、物理性状恶化和土壤污染等退化特征的基础上 ,指出了黑土退化的自然因素和人为因素 ,并探讨了黑土退化的防治和可持续农业 ,这对于提高黑土地区土壤的生产力 ...
陆继龙
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Shuitu Baochi Xuebao, 2017 选取3种东北黑土区有代表性的侵蚀性降雨（60，90，120 mm/h）和3个典型坡度（3°，5°和7°），采用模拟降雨试验方法，研究不同降雨强度和坡度下黑土区土质道路路面径流量、侵蚀量以及产流产沙过程的变化特征。结果表明：不同降雨强度和坡度试验处理的径流量主要变化于56.3～61.8 mm；而路面侵蚀速率随降雨强度和坡度的增加分别增大1.8～11.0倍和1.2～10.0倍，且二者相互促进，共同影响土质道路路面土壤侵蚀。此外，降雨强度对黑土区土质道路路面产流率变化过程的影响明显，而坡度的影响较小 ...
沈海鸥 +5 more
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Shuitu Baochi Xuebao, 2005 在GIS技术的支持下,利用137Cs含量的分异规律对土壤侵蚀的发生、分布进行了研究,并对不同土地利用背景下土壤侵蚀的空间分布规律进行了定量研究。通过137Cs强度的空间差异,分析了土壤侵蚀的强度及区域差异,及其与区域土地利用、土地覆盖变化的相互关系。结果表明:(1)黑河中游山前平原区属中度侵蚀,其土壤侵蚀强度依次为荒地>耕地>草地,草地开垦为耕地将加剧土壤侵蚀;(2)研究区内每年耕作土地的土壤侵蚀量达0 2亿t,草地的土壤侵蚀量达0.4亿t,荒地的土壤侵蚀量达1 2亿t ...
马海艳 王根绪 程国栋 王军德
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