西藏自治区土地资源的适宜性评价与利用

本文综合评价了西藏自治区土地资源的适宜性及其质量．阐明了影响土地资源潜力发挥的主要限制因素，分析了土地资源利用现状、存在问题和开发潜力。并在此基础上、提出了西藏自治区土地资源合理开发利用的方向、对策和措施。     

NATURAL EROSION RATES AND THEIR PREDICTION IN THE IDAHO BATHOLITH1

ABSTRACT: Natural rates of surface erosion on forested granitic soils in central Idaho were measured in 40 m² bordered erosion plots over a period of four years. In addition, we measured a variety of site variables, soil properties, and summer rainstorm intensities in order to relate erosion rates to site attributes. Median winter erosion rates are approximately twice summer period rates, however mean summer rates are nearly twice winter rates because of infrequent high erosion caused by summer rainstorms. Regression equation models and regression tree models were constructed to explore relationships between erosion and factors that control erosion rates. Ground cover is the single factor that has the greatest influence on erosion rates during both summer and winter periods. Rainstorm intensity (erosivity index) strongly influences summer erosion rates, even on soils with high ground cover percentages. Few summer storms were of sufficient duration and intensity to cause rilling on the plots, and the data set was too small to elucidate differences in rill vs. interrill erosion. The regression tree models are relatively less biased than the regression equations developed, and explained 70 and 84 percent of the variability in summer and winter erosion rates, respectively.     

论冲压设备机械伤害事故的成因与预防

任何事故的发生都离不开人的不安全行为和物的不安全状态，作为危险性较大的冲压设备机械的伤害事故的产生也不例外。为此，从冲压设备机械伤害事故的两起案例入手，具体分析形成事故的因素并提出预防事故发生的有效措施。     

岷江上游半干旱河谷土壤成土特征研究：以大沟流域为例

岷江上游半干旱河谷位于新构造运动活动带，其土壤形成和发育过程有着鲜明的区域特征。本文结合该区域的自然地理特点，综合分析各成土因素和土壤性状，对该区域土壤的成土特征进行了深入的分析和研究。     

非点源污染模型中土壤侵蚀因子研究进展

非点源污染模型是进行非点源污染模拟研究的重要手段，而土壤侵蚀模型是非点源污染模型的基础，土壤侵蚀因子的研究是土壤侵蚀模型的重要基础。本文对国内外主要土壤侵蚀因子研究的成果进行了概述，并指出在今后相当一段时期内，土壤侵蚀因子的研究仍是土壤侵蚀模型研究的重要工作。     

Comparison of Soil Extraction Isotherms of Soil Samples Saturated With Nonpolar Liquids

In multiphase systems capillary pressures play a significant role on fluid movement and retention. The facility to predict the effect of different thermal remediation strategies requires the knowledge of the effect of temperature on capillary pressure-saturation relationships in the soils. The objective of recent study was (a) to develop a technique for routinely measuring the pressure-saturation curves of soil samples saturated with a nonpolar liquid at different regulated temperatures (b) to build a database using the measured pressure-saturation curves and the physical, chemical properties of the model soils (c) to establish the dependence of nonaqueous phase liquid retention on the soil properties and the temperature. The retention curves (extraction isotherms) with nonaqueous phase liquid were determined using a modified pressure plate extractor. The wetting phase was a non-aromatic hydrocarbon distillation product. Pressure plates were designed and constructed in the laboratory of our department. The temperature was held constant at 20, 40 and 60 ^∘C. Statistical analysis was performed involving selected soil parameters and the measured nonaqueous phase liquid retention data. The results show that knowing some easily measurable soil parameters (bulk density, particle size distribution, humus and lime content) we can estimate the nonaqueous phase liquid retention of the soils. The measured “extraction isotherms” provide essential information about the temperature-dependency of pressure-saturation curves.     

时域反射仪结合土钻法测定土壤容重

土壤水分是土地持续利用、水资源规划与管理、环境化学、节水农业技术研究的基础。介绍了时域反射仪（TDR）及其测定土壤水分的方法及应用，并利用时域反射仪结合土钻法测定土壤容重，与经典的环刀法测定土壤容重进行了比较，结果表明：两种测定结果存在一定的差异，TDR结合土钻法测定土壤容重能连续测定而且稳定性好。     

我院一年级学生思想政治状况调查报告

这篇报告是在对我院一年级学生思想政治状况调查的基础上写成的.文章从十个方面对对调查的结果进行了简要的总结.并对调查和总结中的问题给予了简要分析.希望以期能对我院学生的成长、教师的教学和领导的管理提供一点参考.     

农业旱灾监测中土壤水分遥感反演研究进展

土壤水分是农业干旱监测最重要的指标之一。文章全面回顾了光学遥感和微波遥感土壤水分遥感反演进展，重点讨论了符种反演方法的优点和不足。光学遥感中，热惯量法和作物缺水指数法可分别较好地应用于裸露地和作物覆盖地的土壤水分监测；距平植被指数、植被条件指数采用了植被指数因子实现农业旱情监测，温度植被指数、植被供水指数和条件植被温度指数同时考虑了作物植被指数和地表温度。微波遥感被认为是当前土壤水分监测中最有效的方法。主动微波遥感空间分辨率较高，但对土壤粗糙度和植被敏感；被动微波遥感空间分辨率低，重访周期短，对大尺度农业旱灾监测具有较大潜力。为提高农业旱灾监测巾土壤水分遥感反演的精度和效率，采用光学遥感和微波遥感的结合可能是较为实际的方法。