934 resultados para Protection and restoration


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随着全球气候变暖和温室效应加剧,干旱和荒漠化成为威胁人类生存和发展的主要 灾害,许多被子植物对干旱胁迫的生理、生态和生化响应已逐步得以报道,但很少有开 展干旱胁迫对雌雄异株植物的影响方面的研究。由于这类植物在长期进化过程中已经在 生长、性比、生殖格局、空间分布、资源配置和生物量分配等方面形成了明显的性别差 异,因此,干旱胁迫必将对其雌雄植株产生不同的生理生态影响。本研究以青杨为模式 植物,采用植物生态、生理及生物化学等研究方法,系统研究青杨雌雄植株在常温、增 温以及喷施外源脱落酸的条件下对干旱胁迫的响应,揭示其在生长形态、生物量分配、 光合作用、用水效率和生理生化等方面的性别间差异。主要研究结果如下: 1. 青杨雌雄植株对干旱胁迫的综合响应。 与较好水分条件相比,干旱胁迫显著降低了青杨雌雄植株的光合作用和生长发育, 影响了许多生理生化过程,并导致雌雄植株在生长发育、气体交换、用水效率、膜脂抗 氧化和抗氧化系统酶活性方面表现出显著的性别间差异。在较好水分条件下,雌雄植株 之间在株高、基径、生物量、净光合速率、蒸腾速率、用水效率以及丙二醛、脱落酸和 游离脯氨酸等生化物质含量方面均无显著差异。但在干旱胁迫下,雄株在生长发育、气 体交换、水分利用效率、膜脂过氧化保护和抗氧化系统酶活性方面均显著高于雌株,表 现出比雌株更高的株高、基径、叶面积、总叶片数、总生物量、总色素含量、类胡萝卜 素含量、净光合速率、蒸腾速率、羧化效率、光系统II最大光化学效率、内在水分利用 效率、碳同位素组分、过氧化氢酶和过氧化物酶活性等,而在CO2补偿点、比叶面积、 叶绿素a/b、丙二醛、脱落酸和超氧化物歧化酶活性等指标上显著低于雌株。与雌株相比, 雄株表现出更高的干旱胁迫适应能力,而雌株的生长发育和生理生化过程更易遭受干旱 胁迫的影响。 2. 干旱胁迫下的青杨雌雄植株对增温处理的综合响应 与环境温度相比,增温在干旱胁迫前后均显著促进了雌雄植株的生长发育、气体交 换,降低水分利用效率,影响生化物质含量,并促使青杨雌雄植株之间在干旱胁迫下表 现出显著的差异。在较好水分条件下,增温导致雌株的株高、基径、叶面积、总叶片数、 总生物量和超氧化物歧化酶活性显著高于雄株,而用水效率、丙二醛、脱落酸和游离脯 氨酸、抗坏血酸过氧化物酶和过氧化物酶活性低于雄株。在干旱胁迫下,增温将导致雄 株的株高、基径、叶面积、总生物量、净光合速率、蒸腾速率、气孔导度、总色素含量、 相对含水量、过氧化氢酶和抗坏血酸过氧化物酶活性等显著高于雌株,而光系统II 最大 光化学效率、内在水分利用效率、碳同位素组分、丙二醛、脱落酸、游离脯氨酸和超氧 化物歧化酶活性显著低于雌株。与雄株相比,水分较好条件下的增温有利于促进雌株的 生长发育,并在生理生态特征上优于雄株。而干旱胁迫下的增温则加剧了水分胁迫强度, 致使雌株的生长发育遭受比雄株更多的负面影响。 3. 干旱胁迫下的青杨雌雄植株对喷施外源脱落酸处理的综合响应 与对照相比,在干旱胁迫下喷施外源脱落酸可显著增加青杨雌雄植株的生长发育、 气体交换、降低水分利用效率,影响了生化物质含量,并导致青杨雌雄植株之间在干旱 胁迫下表现出显著的生理生态差异。在干旱胁迫下,喷施外源脱落酸致使雌株的株高、 叶面积、叶干重、细根干重、总生物量、净光合速率、蒸腾速率、气孔导度、光系统II 最大光化学效率、非光化学淬灭系数、相对含水量、总光合色素、类胡萝卜素、脱落酸、 超氧化物歧化酶和过氧化物酶活性的增加量显著高于雄株,而根重比、根冠比、细根/ 总根、比叶面积、内在水分利用效率、碳同位素组分、丙二醛、脯氨酸、过氧化氢酶和 抗坏血酸过氧化物酶活性等指标的减少量上显著低于雄株。与对照相比,干旱胁迫下的 喷施外源脱落酸则一定程度能减缓植株遭受胁迫的压力,促进植株生长和气体交换,减 少了植株体内的过剩自由基数量,并促使雌株的生长发育和光合能力显著提高,增强其 抗干旱胁迫能力。 With development of global warming and greenhouse effect, drought and desertification have been became main natural disasteres in resent years. Studies on ecophysiological responses of most angiosperm species to environmental stress have been reported, but little is known about dioecious plant responses to drought stress. Since significant differences on growth, survival, reproductive patterns, spatial distribution, as well as resource allocation between males and females of dioecious plant have been formed during evolutionary process, sexual different ecophysiological responses should be caused by drought stress. In this experiment, Populus cathayana Rehd. was used as model plant to study the sex-related responses to drought by using the ecological, physiological and biochemical methods under normal atmospheric temperature, elevated temperatures and exogenous abscisic acid (ABA) application treatment respectively, and to expose the sexual differences in growth, biomass allocation, photosynthesis, water use efficiency and some biochemical material contents in the males and females of dioecious plant. The results are follows: 1. A large set of parallel responses of males and females of P. cathayana to drought stress Compared with well-watered treatment, drought significantly decreased growth and photosynthesis of P. cathayana individuals, affected some physiological and biochemical processes, and induced males and females to exhibit obvious sexual differences in growth, gas exchange, water use efficiency, lipid peroxidation protection and antioxidant defenses enzyme system. Under well-watered treatment, there were no significant sexual differences in height growth (HG), basal diameter (BD), dry matter accumulation (DMA), net photosynthesis rate (A), transpiration (E), water use efficiency (WUE), and malondialdehyde (MDA), abscisic acid (ABA) and praline (Pro). However, under drought stress, males were found to exhibit higher HG, BD, leaf area (LA), total leaf number (TLA), DMA, total chlorophyll contents (TC), carotenoids content (Caro), A, E, carboxylation efficiency (CE), the maximum efficiency of PSII (Fv/Fm), intrinsic water use efficiency (WUE ), carbon isotope composition (δ13C), catalase (CAT), peroxidase (POD) and lower CO2 compensation point (Γ), specific leaf area (SLA), chlorophyll a/b ratio (Chla/Chlb), MDA, ABA and superoxide dismutase (SOD) than females. The results suggest that males possess greater drought resistance than do females and females suffer more negative effect on growth and development, physiological and biochemical processes than males under drought stress. 2. A large set of parallel responses of drought-stressed males and females of P. cathayana to elevated temperatures Compared with environmental temperature, elevated temperature treatment significant increased growth and gas exchange, decreased water use efficiency, changed some biochemical material contents of P. cathayana individuals, and induced males and females to exhibit obvious differences under drought stress. Under good water condition, elevated temperature treatment caused females to show significant higher HG, BD, LA, TLN, DMA, SOD activity, and great lower WUE, MDA, ABA, Pro, ascorbate peroxidase (APX) and POD than do males. On contrary, under drought condition, elevated temperature treatment induced males to exhibit higher HG, BD, LA, DMA, A, E, stomatal conductance (gs), relative water content (RWC), CAT, APX activity but lower Fv/Fm, WUE, δ13C, MDA, ABA, Pro, SOD activity than do females. The results suggest that females will benefit from elevating temperature under good water condition by possessing better ecophysiological processes than that of males, but will suffer from greater negative effects than do males when grown under drought stress with elevated temperature treatment. 3. A large set of parallel responses of drought-stressed males and females of P. cathayana to exogenous ABA application Compared with controls, exogenous ABA application under drought greatly increased growth and gas exchange, decreased water use efficiency, changed some biochemical material contents in P. cathayana individuals, and induced males and females to exhibit obvious sexual differences under drought. Under drought stress, exogenous ABA application induced females to exhibit more increases in HG, LA, leaf weight (LW), fine root weight (FRW), DMA, A, E, g, Fv/Fm, non-photochemical quenching coefficient (qN), RWC, TC, Caro, ABA, SOD, POD s activity than males, but to show lower decreases in root/weight ratio (RWR), root mass/foliage area ratio (RF), fine root/total root ratio (FT), SLA, WUE, δ13C, MDA, Pro, CAT, APX than males. The results suggest that exogenous ABA application under drought stress will eliminate negative damages caused by drought stress at a certain extent,promote the growth and gas exchange of plant and decrease the number of superfluous 1O2 in plant cells of males and females of P. cathayana. Furthermore, exogenous ABA application promoted more drought resistance in females than in males by increasing more growth and photosynthetic capacity in females under drought stress.

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Landscape agriculture is the combination of landscape ecology and agriculture. Its basic idea is from the system theory and landscape ecology. Now landscape agriculture is getting more and more attention because of its multi-functional roles. For example, it can exploit the agricultural ecosystem more rationally, make full use of the self-adjustment function of the natural patches and corridors in the field, as well as the effects from landform types and topological components. It uses regenerative biological energy to a large extent, constitutes beautiful scenic view and protects the diversity of genetics, species, ecosystems and landscapes. Landscape agriculture emphasizes environment improvement, bio-diversity protection and tourism development, thus provides new possibility for the increase of economical benefits and gets the positive feedback loop started. An example from the former Soviet Union is presented as well in this paper

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对农业、环境建设、自然资源和农业生态经济“专家”系统建设等限制黄土高原生态农业建设和发展的有关的重大问题进行了理论分析 ,探讨了其存在的问题和运作设想 ,以求得在上述几个领域内为黄土高原生态农业、环境保护和经济的发展提供参考

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对黄土丘陵区退耕地植被特征的时空变异性进行了研究。结果表明,不同植被类型区植被特征之间差异不是很显著,仅延安与安塞在物种丰富度之间和安塞与吴旗在物种多样性之间存在较显著的差异(0.01

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The conservation of species requires preservation of natural habitats,where the integrity of natural habitats has been severely disturbed and species goes extinct. All natural habitats are continuing to decline both inside and outside of reserves. Habitat change is partly a natural process (e.g., succession), but human activities have accelerated the process so that natural rate of renewal is insufficient to maintain natural habitats. This paper provided concept, methods of habitat renewal, habitat mitigation and their implication to protection and exploitation of natural resource. We argue that our only resourse, in light of these scenarios, is to adopt a new conservation strategy that considers the importance of habitat renewal and habitat mitigation in addition to habitat preservation. Accordingly, in our management decision, we must not only choose the size of area to preserve ,but also the size of area to balance habitat loss with habitat renewal or habitat mitigation. Finally, we explored the application of habitat renewal and habitat mitigation in regional sustainable development of Liaohe Delta wetland.

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根据不同的生物气候状况 ,可将黄土高原分成五个生物气候区 :暖温带湿润半湿润森林区、暖温带半湿润半干旱森林草原区、中温带半干旱典型草原区、中温带干旱半干旱荒漠草原区以及中温带干旱草原化荒漠区。紧密结合上述生物气候区域特征 ,将生态学的有关原理引入到该区的治理与生态恢复中 ,提出了治理黄土高原的新模式 :正确实施生物措施 ,人工模拟天然生态系统。该区的生态恢复应从系统的角度考虑 ,并严格遵守生态学的有关规律在不同的生物气候区构建与该区大环境一致的不同的生态系统 ,改变过去那种在黄土高原全面造林而又成效不佳的做法

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工程措施和耕作措施是有效实施造林种草的必要条件 ;2 5°以上的陡坡地退耕后主要应作为营造水土保持林灌草的生态保护用地 ;应把天然植被保护、改良放在与退耕还林还草同等重要位置 ;建议将科学技术与专业科技力量直接切入生态环境建设 ,以充分发挥支撑作用

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This paper illustrated the relationships between P. koraiensis and animal,and discussed the effect of cones picking on quantity and structure of animal, P. koraiensis regeneration,biomass,services,structure and succession,and nutrient cycle of the ecosystem.It showed that cones picking has damaged the integrity and function of ecosystem health in term of the concepts and characteristics of ecosystem health.The paper was aiming at the strategies to resolve the relationships between cones picking and ecosystem health maintaining in order to give scientific foundations for protection and management of broad-leaved P.koraiensis forest in Changbai Mountain.

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A series of biodegradable polylactide-based polyurethanes (PLAUs) were synthesized using PLA diol (M-n = 3200) as soft segment, 4,4 '-diphenylmethane diisocyanate (MDI), 2,4-toluene diisocyanate (TDI), and isophorone diisocyanate (IPDI) as hard segment, and 1,4-butanediol as chain extender. The structures and properties of these PLAUs were studied using infrared spectroscopy, differential scanning calorimetry, tensile testing, and thermomechanical analysis. Among them, the MDI-based PLAU has the highest T-g, maximum tensile strength, and restoration force, the TDI-based PLAU has the lowest T-g, and the IPDI-based PLAU has the highest tensile modulus and elongation at break. They are all amorphous. The shape recovery of the three PLAUs is almost complete in a tensile elongation of 150% or a twofold compression. They can keep their temporary shape easily at room temperature (20 degrees C). More importantly, they can deform and recover at a temperature below their T-g values. Therefore, by selecting the appropriate hard segment and adjusting the ratio of hard to soft segments, they can meet different practical demands for shape memory medical devices.

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The method for the measurement of the pure mechanical wear loss for 321 stainless steel, 1045 steel and pure iron in the study of the synergy between corrosion and wear was studied, The methods studied included the measurement in distilled water, by cathodic protection and by adding inhibitor KI, and all were compared with the wear loss in air. The experiment showed that the pure mechanical wear losses and friction coefficients obtained by the three methods were close to each other and can be used to calculate the various wear components in the study of the interaction of corrosion and wear, but the measurements in distilled water for pure iron and 1045 steel are not recommended due to their corrosion.

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在图像成像、复制、扫描、传输、显示等过程中,不可避免地要造成图像的降质,如图像模糊、噪声干扰等。而在许多应用领域中,又需要清晰的、高质量的图像,因此,图像复原(如去噪、去模糊等)具有重要的意义。图像复原的目的是对降质图像进行处理,使其恢复成原始图像。它是图像处理、模式识别、机器视觉的基础,因而受到广泛的研究,并在天文学、遥感成像、医学影像等领域获得广泛的应用。图像复原的传统方法主要是进行图像滤波。由于图像的大部分信息存在于图像边缘部分,因此要求图像滤波既能去除图像的模糊和噪声,同时又能保持图像的细节。由于图像细节和噪声在频带上混叠,导致图像的平滑和边缘细节的保持成为一对矛盾。传统的滤波方法难以处理这类问题。近年来发展起来的偏微分方程图像处理技术,为解决图像复原中的这一矛盾提供了新途径。本论文共分五个部分。第一部分给出了图像复原的数学模型并讨论了其发展现状,综述了图像复原问题的规整化理论及方法,阐述了图像复原的基本过程和影响因素。第二部分研究了基于奇异值分解和能量最小原则的图像自适应降噪算法。基于有界变差的能量降噪模型的代数形式,提出了一种自适应图像降噪算法。该算法通过在矩阵范数意义下求能量最小,自适应确定去噪图像重构的奇异值个数。这一算法的特点是将能量最小原则和奇异值分解结合起来,在代数空间中建立了一种自适应的图像降噪算法。与基于压缩比和奇异值分解的降噪方法相比,该算法避免了图像压缩比函数及其拐点的计算。因此求解更加简单。第三部分研究了基于各向异性扩散的图像降噪和抖动消除算法。提出了两种算法,一、提出了一个由各向异性扩散方程定义的非线性图像滤波算子。与Perona,Malik提出的算子类似,该算子能够去除噪声,而且性能稳定,处理后的自然图像看上去清晰而且对比度也得到增强。对于图像抖动产生偏移,二、提出了一种基于各向异性非线性扩散以及抖动估计的抖动消除算法。这种各向异性非线性扩散的模型由两项组成,即扩散项以及强制项。基本思想就是对于边缘点以及光滑区域的点分别进行处理,利用Newton-Raphson算法计算最小化抖动误差,估计出抖动偏移量,从而得到抖动消除之后的图像。第四部分研究了基于四阶偏微分方程和基于高斯曲率的图像降噪算法。针对低阶的非线性偏微分方程进行图像去噪,如总变差、平均曲率流等去噪模型,会产生阶梯效应这一缺陷,即易得到分段常量结果的缺陷,提出了一种基于四阶偏微分方程的图像降噪算法,并给出了实验结果。提出了一种改进的基于高斯曲率和偏微分方程的图像降噪算法。该算法能够得到一个稳态的非平凡解,从而能够避免中止时间的选取。第五部分研究了基于C-V降噪模型的图像半盲复原算法。基于C-V降噪模型,提出了一种图像半盲的复原算法,即假定图像退化的模型已知,如高斯模糊,但是高斯核的方差未知,通过构造能量函数,将能量函数的极小问题转化为一个变分极小问题,由变分原理得到相应的欧拉-拉格朗日方程。这里设计的算法将未知数的个数由Leah Bar模型的三个减少为两个,最后估计出来高斯核的方差比Leah Bar 算法更加接近于真值。

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The Qaidam Basin constitutes a major portion of the northeastern Tibetan Plateau, and an understanding of its tectonic development will help decipher how the Tibetan Plateau was formed. It is shown that Late Cretaceous–Paleocene deposits of the western Qaidam Basin can be well correlated with their counterparts of the southwestern Tarim Basin, implying that the two regions were originally connected or were in the same depositional basin during that period of time. The Qaidam Basin commenced subsiding due to crustal shortening in the Eocene, and it has subsequently evolved into an independent basin since the Miocene. The main depocenter was noticeably persistent in the middle of the western Qaidam Basin from Eocene to Miocene time, and then it shifted to the east. On the basis of spatial stratigraphic correlation and restoration of sedimentary processes, we surmise that there existed a proto–Qaidam Basin during the Paleogene, where the Suhai and Kumukol Basins represent its northern and southern margins, respectively. The Suhai and Kumukol Basins were subsequently isolated from the Qaidam Basin as a result of basinward thrusting in basin-margin areas. It is shown that the western Qaidam Basin experienced three distinct stages: the first stage was characterized by a simple synclinal depression; the second stage was marked by occurrence of reverse faults at inflection points of the megafold and continuous subsidence in the middle of the basin; and the third stage featured intrabasinal deformation and uplift. The eastern Qaidam Basin underwent a diverse evolution and became the main depositional area in the Quaternary. It is suggested that the Qaidam Basin should be generated as a result of crustal buckling or folding, manifesting itself as a synclinal depression. The crustal folding model can account for a number of observations, including localization of the depocenter in the middle of the basin, nearly concomitant deformation on the south and north sides of the Qaidam Basin, occurrence of major high-angle reverse faults at basin margins, and generation of adjacent intermontane Suhai and Kumukol Basins. A tectonic model is accordingly advanced to illustrate Cenozoic tectonics of the Qaidam Basin.

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Geopolymer gelatinous material was prepared by ferroalloy slag (signed with NKT in laboratory) and circulating fluidization bed slag (CFB slag, signed with NM in laboratory) produced from Heshan city, Guangxi zhuang autonomous region, China. The mechanical properties of the geopolymer made of high content ferroalloy slag can reach the standard of 42.5# portland blastfurnace-slag cement, and it’s processing technology is more simple and not need of mill and burn and will not produce harmful gas. By means of chemical and XRD analyses, it is concluded that NKT is a kind of acidity water-granulated slag with better activation and fit to be activated by alkali activators. Low-cost industrial gypsum (signed with NG in laboratory), analytic reagent oxide(signed with NH in laboratory) and sulfate(signed with NS in laboratory) were selected as alkali activation in the experiment. The results showed NH is a good alkali activator for NKT. Both NH and NG can activate ferroally slag’s activities, but NS can’t alone. The activation effect of superimposing activation of NH and NG excel by separateness. Based on those experiments, optimization compounds were carried out: (1) NKT: NH: NG = 80: 10: 10 and (2) NM: NKT: NS: NG: NH = 10: 70: 2: 8: 10。. The soundness of the test blocks is good by boiling examination. Through XRD, SEM, IR, NMR analyses of geopolymer, the reaction mechanism of geopolymer prepared by alkalescent activating in solid wastes was discussed in the thesis first. It is point out, there is difference in reaction mechanism between traditional geopolymer preparation and the preparation of alkalescent activating solid wastes because NG is a industry product. There is the similar process of depolymerization and reunion of Si-O bond. The latter preparation process generate new subtance but the former doesn’t. In the experiment, we found a performance of NKT that the water requirement of normal consistency of geopolymer reduces with increasing content of NKT. The result shows NKT has some ability to reduce water requirement. The performance is worthy of further research and utilization. Making use of solid wastes to prepare geopolymer, not only can settle environment problem caused by a great deal of dump of NKT, but also settle the shortage of natural resources. Moreover it could take economic, environmental and social benefits and settle thoroughly contradiction in the environment protection and regional economy development and promote circulation economy development.

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The engineering geological properties of Neogene hard clays and related engineering problems are frontiers in the fields of Engineering Geology, Soil Mechanics and Rock Mechanics. Recently, it has been recognized that Neogene hard clay is the intermediate type of material between the soil and the rock. Many aspects of them, such as sampling, testing, calculating and engineering process, are special, which could not be researched by means of theories and methods of traditional Soil Mechanics of Rock Mechanics. In order to get real knowledge and instruct the engineering practice, intersect studying of multiple disciplines, including Engineering Geology, Soil Mechanics and Rock Mechanics, etc., is necessary. Neogene hard clay is one of the important study objects of regional problem rocks & soils in our country, which extensively distributed in China, especially in Eastern China. Taking the related areas along the middle line of the Project of Transferring Water from the South to the North (e.g. Nanyang basin, Fangcheng-Baofeng area and Handan-Yongnian area), South-west of Shandong, Xu-Huai area and Beijing area, etc. as main study areas, the paper divided Neogene hard clays into reduction environment dominated origin and oxidation environment dominated origin, which distributed on areas western and eastern to Mount Taihangshan respectively. Intermediate types are also existed in some areas, which mainly distribute near the edges of depositional basins; they are usually of transitions between diluvial and lacustrine deposits. As to Neogene hard clays from Eastern China, the clay particle content is high, and montmorillonite or illite/montmorillonite turbostratic mineral is the dominating clay mineral. The content of effective montmorillonite is very high in each area, which is the basis for the undesirable engineering properties of Neogene hard clays. For hard clays from the same area, the content of effective montmorillonite in gray-greenish hard clay is much higher than that in purple-brownish or brown-yellowish hard clay, which is the reason why the gray-greenish hard clay usually has outstanding expansive property. On the other hand, purple-brownish or brown-yellowish hard clay has relatively less montmorillonite, so its property is better. All of these prove that the composition (clay mineral) of Neogene hard clay is the control factor for the engineering properties. Neogene hard clays have obvious properties such as fissured, overconsolidated and expansive, which are the main reasons that many engineering problems and geological harzards usually occur in Neogene hard clays. The paper systematically elaborates the engineering properties of Neogene hard clays from Eastern China, analyses the relationships between engineering properties and basic indexes. The author introduces the ANN method into the prediction of engineering property indexes of hard clays, which provides a new way for quantitatively assessment and prediction of engineering property indexes. During investigation in the field, the author found that there exists obvious seam-sheared zone between different hard clays in Miocene Xiacaowan formation in Xu-Huai area. Similar phenomenon also exists near the borderline between Neogene hard clays and underlying coal measures in the Southwest of Shandong province, which could be observed in the cores. The discovery of seam-sheard zone has important theoretical and practical significance for engineering stability analysis and revealing the origin of fissures in Neogene hard clays. The macrostructure, medium structure and microstructure together control the engineering properties of hard clays. The author analyses and summarizes the structural effects on hard clays in detail. The complex of the strength property of hard clays is mostly related to the characteristics of fissures, which is one of the main factors that affect the choice of shear strength parameters. So structure-control theory must be inseparably combined with composition-control theory during the engineering geological and rock/soil mechanics research of hard clays. The engineering properties, such as fissured, overconsolidated and expansive, control the instability of engineering behaviors of Neogene hard clays under the condition of excavation, i.e. very sensitive to the change of existence environment. Based on test data analysis, the author elaborates the effects of engineering environment change on the engineering properties. Taking Nanyang basin as example, the author utilizes FEM to study the effects of various factors on stability of cutting canal slopes, than sets forth the characteristics, development laws and formation mechanism of the deformation and failure of hard clay canal slopes, summarizes the protection and reinforcement principles, as well as the protection and remedy steps. On the basis of comparison of engineering properties of domestic and foreign Neogene muddy deposits, in the view of whole globe and associated with the geological characteristics of China, the paper demonstrates that the intermediate type of the material between the soil and the rock, named "hard clay/soft rock", which can not be separated abruptly, really exists in China. The author has given a preliminary classification based on its geological origin and distribution law, which is very significant for promoting the mixture of Engineering Geology, Soil Mechanics and Rock Mechanics. In the course of large scales engineering construction in China, many engineering experiences and testing data are gained, summarizing these testing results and automatically managing them with computer technology are very necessary. The author develops a software named "Hard Clay-Soft Rock Engineering Geological Information Management and Analysis System (HRGIMS)", realizes the automatic and visual management of geo-engineering information, on the basis of information management, the functions of test data analysis and engineering property prediction are strengthened. This system has well merits for practice and popularization.

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Understanding relationship between environmental protection and economic development is crucial to form practical environmental policy. At micro level, implementation of environmental regulations often causes production mills adjustment of technology which might leads to change of productive efficiency and cost, which, in turn, determine effort level of mills and even local government in pollution control. Using a stochastic frontier production model and a set of survey data on 126 paper mills from six provinces of China, we measure the technical efficiency changes and analyze the determinants of efficiency. in particular, we examine impact of environmental policy on paper mills' efficiency, using an indicator of environmental policy-the levy ratio of COD. We also estimate a simultaneous-equation model in which the levy rate and emission are jointly determined. The results indicate that there have been efficiency improvements during 1999-2003, when enforcement of environmental regulations have been tightened. The impacts, nevertheless, are different for different types of mills. We also find the levy ratio, which is influenced by both the local social and economic conditions and the characters of paper mills, such as scale, has strong impact on the abatement of the pollutant-COD. Additionally, paper mills' technical efficiency has positive effect on the reduction of the emission intensity of the pollutant-COD. These results lead a set of implications pertinent to policy improvement.