The effects of land use and its patterns on soil properties in a small catchment of the Loess Plateau

Due to relatively strong human activities in the hilly area of Loess Plateau,the natural vegetation has been destroyed,and landscape pattern based on agricultural land matrix was land use mosaic composing of shrub land,grassland,woolland and orchard.This pattern has an important effect on soil moisture and soil nutrients.The Danangou catchment,a typical small catchment,was selected to study the effects of land use and its patterns on soil moisture and nutrients in this paper.The results are as follows:The comparisons of soil moisture among seven land uses for wet year and dry year were performed:(1)the average of soil moisture content for whole catchment was 12.11% in wet year,while it was 9.37% in dry year;(2)soil moisture among seven land uses was significantly different in dry year,but not in wet year;(3) form wet year to dry year,the profile type of soil moisture changed from decreasing type to fluctuation-type and from fluctuant type to increasing type;(4)the increasing trend in soil moisture from the top to foot of hillslope occurred in simple land use along slope,while complicated distribution of soil moisture was observed in multiple land uses along slope.The relationships between soil nutrients and land uses and landscape positions were analysed:(1)five nutrient contents of soil organic matter(SOM),total N(TN),available N(AN),total P(TP) and available P(AP) in hilly area were lower than that in other areas.SOM content was less than 1%,TN content less than 0.07%,and TP fallow land and cropland,and higher level in soil fertility was found in crop-fruit intercropping land among croplands;(3)soil nutrient distribution and responses to landscape positions were variable depending on slope and the location of land use types.     

"加油!向前冲!"--荆门分公司联合二车间安全生产月岗位练兵比赛侧记

6月15日,荆门分公司联合二车间彩旗飘扬,横幅招展,一场以宣传安全月为主题的"发展安全,提高技能"的岗位练兵活动正在进行.     

白洋淀北岸农田土壤特性的表征

本文采用标准方法，测定了白洋淀北岸部分农田土壤的粒度组成、ｐＨ和有机碳含量等指标，对该地区土壤的特性进行了表征分析。结果表明，土壤的平均粒度分布大于２０μｍ的占５２．７３％，主要属于砂壤土。与１０年前相比，ｐＨ值变化不大；而有机碳含量是１０年前的１．２６倍。ｐＨ随土壤的垂直深度而略有增加，而有机碳含量则随土壤的垂直深度而减少。     

垃圾焚烧烟气中二E英的危害及治理

分析了垃圾焚烧过程中产生二Ｅ英的原因及危害，给出了相应的整治措施。     

不同农业灌溉用水对土壤理化性质影响的研究

编者按 土壤管理和土壤利用方式影响着土壤的发育方向和土壤的性质(如土壤质地、土壤环境、土壤生态等).农业生产中对土地的不同管理措施或方式直接影响着农业土壤的发展方向和土壤环境变化.城市污水往往有较高的肥力,利用其灌溉农业,即能利用水源又能利用其中的肥源,有利于农业生产.     

分子官能团贡献法在预测有机物理化性质中的应用前景

本文综述了ＵＮＩＦＡＣ基团贡献法的基本原理和方法，近年来的发展与修订。以及它在预测有机物理化性质方面的应用。     

会计电算化专业实践课程的建设

本主要论述了会计综合实训、电算化会计实训、会计分岗位实训的内容、组织及考核方法，通过系列实践课程的建设，加强学生对会计理论的理解、基础方法的运用和基本技能的训练，达到理论教学和会计实践的统一。     

安全带成了"救命索"

安全带,有些人认为它是无足轻重的物件,然而,我对它却情有独钟.在两年前的一次意外险情中,它成了我的"救命索". 两年前,我在前线修井队实习锻炼,因为踏实肯干、责任心强而被班里人看重.师傅们经常主动向我传授操作技能,还让我到"关键岗位"、"重要部位"锻炼,期望我"速成"后能挑起班里的大梁.