水土

Stability of 14 high-cut slopes in Guangdong province is analyzed with typical rock mass structure analysis method and stereographic projection method, and with the numerical simulation method UDEC this paper simulated the excavation and reinforcement courses of the important slopes. Some conclutions and suggestions are based the analysis above.

本文结合广东某省道沿线14个高陡岩石边坡的开挖和支护方案的选择设计，运用常用的岩体结构分析方法和赤平投影方法对边坡的稳定性进行了分析，采用UDEC数值模拟方法对一些重点边坡的开挖支护进行了模拟，得出了以下一些结论： 1、边坡支护形式的选择应遵循"安全绿色、水土保持、恢复自然、环保之路"的设计原则。

Stonework aids erosion control and soil retention.

石雕艾滋病防治水土流失和土壤保持。

But stover protects against soil loss to wind and water.

但是干草会防止水土流失。

The subalpine meadows in Luyashan Mountain are one of the typical meadows in north China and play an important role in water and soil conservation,eco-tourism resource exploitation and bio-diversity protection and so on.

芦芽山亚高山草甸是在华北地区最典型的山地草甸之一，该草甸在水土保持、生态旅游资源开发和生物多样性保护等方面发挥着重要作用。

Soil erosion by wind, as a natural disaster haunts on dry lands, not only degrades soil productivity but also often results in dust blizzard weather. It may cause pollutions of air and water, damages of highway and railway, wear and tear of buildings and machinery and harmfulness in health of people and animals. Therefore, to combat wind erosion means improving the environment for people to live and work, means heightening the living standard of the local people, and means promoting productive forces. But China has a vast land where probably occur wind erosion disasters, the arid, semiarid and subhumid areas of the temperate zone all are potentially hit by wind erosion. To control wind erosion in China is a very arduous task. More difficult is to achieve recognizable effectiveness with lowest cost.

中文题名宁夏土壤风蚀研究副题名外文题名 Estimation of wind erosion in Ningxia 论文作者李玉宝导师王礼先孙保平教授学科专业水土保持与荒漠化防治研究领域\研究方向荒漠化防治学位级别博士学位授予单位北京林业大学学位授予日期2001 论文页码总数100页关键词风蚀土壤风蚀土壤侵蚀馆藏号BSLW /2003 /S157 /14 中国发生土壤风蚀的潜在区域包括温带干旱、亚干旱和亚湿润气候下的广大地区，如何有效地预防和治理土壤风蚀，如何以最小的代价达到满意的防治效果，这是很值得研究的问题。

The water leakages in red soil farmland in northeast of Jiangxi province were studied using large scale weighing lysimeter, time domain reflectometry and tensiometer.

红壤区是我国水土流失严重地区之一，该区降水量大且分布集中，一般认为红壤的入渗透水性能差是引起土壤侵蚀的一个重要原因。

soil erosion intensity ; spatial and temporary change ; the upper basin of Guanting reservoir

对于区域水土流失变化情况的有效监测一向是研究的重点与热

Initial results indicate relief is the best topographic factor in assessment of regional soil and water loss.

初步研究表明，其中地形起伏度是区域水土流失评价的最佳地形指标。

The results show that not only the porosity does greatly affect the windbreak, but also the tree distance does. The distance is not beyond 1.3 to avoid air leak. The tree belt with porosity 31% has bigger windbreak range and better characteristics for abating wind erosion. The tight nubby tree belt is advised to restrain the particles adhering on the leaves refloating for large velocity deficit in trees.

结果表明：不仅林冠疏透度对防护林带的遮蔽防风有明显影响，而且树木间的株距对林带整体的遮蔽效果也有比较显著的影响，为避免穿流风对遮蔽效应的影响，林带宽距比不宜超过1.3；疏透度为31%的网状林带的有效防护范围大，防风效果好而且水土保持性强；紧密型块状林带，林后速度衰减幅度大，可抑制附着在叶片上粉尘的再次扬尘。

People plant trees on the treeless mountain to reduce water and earth loss.

人们在荒丘上种植了树木，以减少水土流失。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。