【摘 要】
：
The actual and potential water erosion rates of soils with different land covers in Hainan Island, China,were estimated based on the universal soil loss equatio
【机 构】
：
Institute of Soil Science
【基金项目】
：
the United Nations Development Program;国家重点基础研究发展计划(973计划)
论文部分内容阅读
The actual and potential water erosion rates of soils with different land covers in Hainan Island, China,were estimated based on the universal soil loss equation (USLE) and a 1:200 000 Soils and Terrain Digital Database (SOTER) database, from which soil water erosion factors could be extracted. 92.8% of the whole island had a current erosion rate of lower than 500 t km-2 a-1. Soil erosion risk was considered to be high because of its abundant rainfall. Without vegetation cover, the potential soil erosion rate would be extremely high and 90.8% of the island would have a soil erosion rate higher than 2 500 t km-2 a-1. Relative erosion vulnerability of different soil zones, landform types, and lithological regions of the island was compared by introducing a relative erosion hazard parameter α. Cambosols developed from siltstone and mudstone in low hill regions were pinpointed as soils with the highest erosion risk in the island.
其他文献
慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)由于气流受限和持续过度充气导致膈肌负荷过重,从而使膈肌结构、代谢和收缩功能发生改变,如肌卫星细胞活化,
疼痛是子宫内膜异位性疾病患者的典型症状之一,反复发作一直是治疗的难点.内膜异位性疾病疼痛产生的机制尚不明确,目前针对疼痛的治疗以非甾体类消炎药、激素类药物为主,但效
外周神经损伤后,受损神经局部往往会出现神经纤维的异常生长增生,于损伤局部形成迂曲、错长,最终形成局部肿块,即所谓创伤性神经瘤,而其中约10％的创伤性神经瘤出现顽固的病理
文章主要分析了经济社会因素对中小学教师心理健康的影响.经济社会因素包括社会威胁、教育环境和经济状况三类指标,教师心理健康状况以SCL-90的9个因子均分为指标.文章分析了
目的：探讨后路原皮肤切口双侧肌间隙入路经Quadrant通道下TLIF术（transforaminal lumbar inter-body fusion）治疗复发性腰椎间盘突出症（recurrent lumbar disc herniation,RLDH）的
目的：研究单节段L4/5棘突间动态稳定装置（Wallis）置入术后1年的L4及L5棘突骨质吸收现象，并行多因素回归分析对可能的原因进行探讨。方法：回顾性研究我科2009年~2011年间行单节段L4
Plant communities were sampled in the lower reaches of the Tarim River, Xinjiang. Theresults showed that there are 23 species belonging to 21 genera in 11 famil
Based on geographical and hydrological extents delimited, four principles are identified, asthe bases for delineating the ranges of the source regions of the Ya
During land transformation process in the human history, naturalized plants were introduced to several land use patterns by thedifferent ways of plant itself.In
朗读是语文教学中的一种重要的训练方法。它不仅能使学生更好地掌握课文的字、词、句，加深领会课文的内容，而且还能提高阅读能力，陶冶学生的情操，发展学生的思维能力和表达能力。