黄土

In this paper, collapse characteristics of intact loess from three typical loess areas under different moisture condition are studied,and the principles of loess collapsibility influenced by water content,dry density as well as pressure and behaviors of these in different loess are approached respectively.

对 3个典型黄土地区的原状黄土样在不同湿度状态下的湿陷特性进行了研究，探讨了含水率、干密度、压力对黄土湿陷性的影响规律，着重从结构性的角度解释了不同地区间黄土湿陷特性的差异。

The results show the mineral taxa, morphological characteristics and the high contents of magnetite and dens revealed the multi-sources and near-derived features of the loess-like loess in Zhifu Island, and the main sources of loess are seabed plain, diluvium and residual sediments in the last glacial period, while thin sediments from Northwest inland desert are rare.

结果表明，芝罘岛黄土状黄土矿物种类、矿物形态特征、磁铁矿和岩屑的高含量等都揭示了黄土来源的多源性和近源性，末次冰期时的海底平原沉积物以及洪积、残积物是芝罘岛黄土状黄土的重要物源，而西北内陆沙漠吹来的细颗粒物质相对较少。

The results show the mineral taxa, morphological characteristics and the high contents of magnetite and deris revealed the multi-sources and near-derived features of the loess-like loess in Zhifu Island, and the main sources of loess are seabed plain, diluvium and residual sediments in the last glacial period, while thin sediments from Northwest inland desert are rare.

结果表明，芝罘岛黄土状黄土矿物种类、矿物形态特征、磁铁矿和岩屑的高含量等都揭示了黄土来源的多源性和近源性，末次冰期时的海底平原沉积物以及洪积、残积物是芝罘岛黄土状黄土的重要物源，而西北内陆沙漠吹来的细颗粒物质相对较少。

So the systematically study of loess landslides are emergently needed. Based on detailed investigation and survey of characteristics of environmental geology, engineering geology, hydrometeorology in Tongchuan, the distribution characteristic and the outer, inner factor of loess landslides are studied; and it is concluded that the rainfall and artificial engineering activity are the leading causes of loess landslide among various factors. Through plenty of tests of soil samples, it is researched that the loess"s physical mechanics characteristics, the loess landslide"s formation mechanism and kinematics mechanism.

本文在详细调查和勘察铜川地区的环境地质、工程地质及气象水文特征的基础上，对黄土滑坡的分布特征和滑坡形成的内外因素进行了深入剖析，认为在各种影响因素中，大气降水和人类工程活动是铜川黄土滑坡的最主要的诱发因素；在采集大量的土样并进行试验的基础上，对黄土的物理力学特征和黄土滑坡形成机理、运动学机理进行了研究，推导出了滑坡运动机理中的孔压参数A_D、B_D分别与孔隙比和饱和度的统计关系。

In order to analyze rheological property and establish constitutive model of Q_2 loess, a series of uniaxial creep experiments on different water content are done .The creep test curves and stress-strain isochronism curves are drawed with the result of experiments and conclusions are reached from the curves. The creep performance of Q_2 loess is different under the different stress level. In the different time the stress-strain isochronism curve has obvious inflection point namely yield stress and the yield stress reduces along with the increase of water content, which can be described by exponential function.

为了分析黄土的流变特性和建立相应的本构模型，本文首先根据对不同含水量的Q_2黄土进行的一系列单轴应力条件的室内蠕变试验结果，分析总结了Q_2黄土蠕变特征和应力—应变等时曲线特征，得出Q_2黄土在不同的应力水平下蠕变变形表现形式不同；在不同的时刻应力—应变等时曲线存在有较明显的拐点，拐点所对应的应力即为屈服应力，屈服应力随着含水量的增大而呈指数形式降低；Q_2黄土可近似看成一种线性粘弹塑性体。

During the Last Interglaciation it was the forest, mainly composed of broadleaves, or forest-grassland at the east and middle part of the Chinese Loess Plateau, and was the forest-grassland at the west part of the Chinese Loess Plateau. It changed to the forest or forest-grassland at the most part of the Chinese Loess Plateau in the Holocene, some kinds of hardwood broadleaves dispersing at the warm temperate and the tropic zones appeared. Now the vegetation at the Chinese Loess Plateau inherits from that during the Holocene, the vegetation have been heavily destroyed owing to the human being actions. The vegetation protection at the Chinese Loess Plateau is a significant problem.

末次间冰期期间气候温暖湿润，黄土高原的中、东部地区主要发育了以落叶阔叶林为主的森林或森林草原植被，黄土高原西部地区主要发育的是以针叶林为主森林草原植被；全新世期间黄土高原的植被状况发生较大变化，黄土高原的大部分地区为森林植被或森林草原植被，植被中还有暖温带落叶阔叶林，并含有少量亚热带种属；现代黄土高原的植被主要还是继承了全新世以来的植被状况，但是由于人类活动的加剧，对黄土高原的植被产生了毁灭性的破坏，因此，如何保护黄土高原的自然植被是我们面临的一个严峻的现实问题。

This paper analyzed the reflection spectrum of loess on different granule diameters and irradiant angles. We found that the influence of loessial dense degree on its polarized reflection changed along with loess's moisture content and angle of incidence.

本文以黄土作为代表性土壤，通过对不同粒径，不同光线入射角黄土反射光谱的分析，我们发现黄土的致密程度对其偏振反射光谱的影响与黄土自身的含水量以及入射角相关。

Through contrasting and analysing the experimental results from these methods, the paper summarizes the regularity of collapsing deformation and the shear strength index changes with the degree of saturation and stress, describes the collapsing deformation properties and strength characters of the collapsible loess in the course of moistening and drying, and describes the influence to collapsing deformation of loess from different paths of stress. Through performing monaxial compression test on samples with different paths of inundation and direction of press, proves the conclusion that collapse has nothing to do with the path of inundation and the collapsible loess has the prominent anisotropy characters.

通过对几种方法得出的试验结果进行对比和分析，总结出黄土的湿陷变形和抗剪强度指标随饱和度以及压力变化的规律，借以描述湿陷性黄土在增湿过程中的湿陷变形性状、强度特性以及不同应力路径对黄土变形特性的影响；按不同的浸水路径和受力方向对土样进行单轴压缩试验，证明了湿陷与浸水路径无关的结论以及湿陷性黄土显著的各向异性特征。

Hilly gullied loess region, the main body of Loess Plateau, is also an eco-economic sensitive area with special landscape pattern. Being an ecological fragile and economically underdeveloped region, environment protection and economic development remain to be double tasks it expects to solve simultaneously.

中文题名黄土高原丘陵沟壑区小流域优化生态－生产范式副题名外文题名 Optimized eco-productive paradigm for small watersheds in hilly gullied Loess Plateau 论文作者孔正红导师张新时院士学科专业生态学研究领域\研究方向学位级别博士学位授予单位中国科学院植物研究所学位授予日期2002 论文页码总数143页关键词农业生态系统优化生态－生产范式小流域黄土丘陵沟壑区馆藏号BSLW /2003 /Q948 /26 黄土丘陵沟壑区是黄土高原的主体部分，也是具有特殊景观格局的生态-经济敏感区。

According to the four highway engineering geological subarea of the loess region, based on a great deal of indoor experiments and existing engineering data, the main physical and mechanical property index of each loess area were re-counted, and the district variational regulation of the loess physical and mechanical property were studied in order to get the characteristic parameter of the loess soil property index providing precious foundation data for the highway engineering construction of the loess region.

本文按照黄土地区的四个公路工程地质分区，以大量的室内试验和已有工程资料为基础，重新统计了各区黄土的主要物理力学性质指标，研究了黄土物理力学性质的区域变化规律，得出黄土土性指标的特征参数，为黄土地区的公路工程建设提供了宝贵的基础资料。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。