河北省土壤退化及其防治对策

土壤退化是地球生态环境恶化的主要表现形式之一，概述土壤生态系统能量与物质运动的失调是土壤退化的根本原因，指出导致土壤退化的具体因素，阐明河北省土壤退化的类型、分布、面积及其危害，提出防治土壤退化的基本对策     

河北省土壤退化及其防治对策

土壤退化是地球生态环境恶化的主要表现形式之一，概述土壤生态系统能量与生物运动的失调是土壤退化的根本原因，指出导致土壤退化的具体因素，阐明河北省土壤退化的类型，分布，面积及其危害，提出防治土壤退化的基本对策。     

金沙江干热河谷典型区（云南）退化土壤的结构性与形成机制

云南金沙江干热河谷区是我国典型的土壤退化区域。通过分析土壤机械组成、团聚体及微团聚体组成、孔隙分布状况等指标，探讨了土壤结构对土壤退化的影响机制。研究发现：1．采用分散率、侵蚀率、团聚度、团聚状况、结构体破坏率、受蚀性指数EVA、孔隙度等量化指标可以较好反映土壤退化程度；2．土壤颗粒分散特性、土壤水稳性团聚体稳定性、土壤孔隙度是土壤结构稳定性评价的三个重要方面，也可反映土壤退化特征。     

中国北方农牧交错带土壤风蚀时空分布

土壤风蚀是干旱、半干旱地区土壤退化的主要过程，定量评价土壤风蚀是分析土壤退化的重要手段。中国北方农牧交错带是土壤风蚀的典型治理区。采用张春来风蚀预报经验模型，以半月为步长，计算中国北方农牧交错带2000-2012年的土壤风蚀模数。结果表明：中国北方农牧交错带的土壤风蚀状况整体有好转；沙地的土壤风蚀最严重，农田次之，草地的土壤风蚀最低；土地利用方式、风速和植被盖度均对土壤风蚀有一定的影响。     

全球土壤退化评价

近几十年来，随着世界人口的急剧增长，人为活动引起的土壤退化日趋增强，原先局部的、次要的变化已转化为便全球性的重大变化，威胁着人类赖以生存的环境，本文阐述了包括中国在内的全球土壤退化类型，退化程度和引起土壤退化的主要人为因素，以便土壤管理者，决策者和实施机构为预测未来变化，防治土壤退化作出决策提供依据。     

长江上游退耕还林区的土壤退化与肥力重建

长江上游退耕还林战略举措的关键技术之一是要模清主该区土壤性状和退化问题,进而肝取行之有效的土壤退化防治措施,尽快恢复生态、保护长江全安。以占该区面积最大的紫色土退化为例,提出了该区土壤退化特征、类型和发生现状。指出该区环境的脆弱性和人为干扰是土壤退化根本成果,建议：（１）建立保护区全面封禁管护（２）构建网格生物篱保持水土增厚土层（３）加强土壤碳氮物质循环强化培肥（４）分带治土造林建立垄沟种植培肥体     

我国南方山区土壤退化及其防治

我国南方山区土壤退化成因主要是土壤及生态系统的脆弱性、人地系统矛盾尖锐、土壤侵蚀的动力作用、盲目开发和工矿建设的影响．应从建设本区稳定平衡的生态系统、调整农业结构、建立持续发展的农业优化模式和政策上采取防治土壤退化的措施．     

卧龙自然保护区土地利用变化对土壤性质的影响

森林景观受干扰后的次生演替、人工林种植与农业耕作等在许多方面影响着土壤性质的变化。研究选取了四川卧龙自然保护区作为研究地点 ,阐述湿润高山区的土地利用方式与土壤性质之间的关系。选择了六种典型的土地利用方式加以比较 ,方差分析结果表明 ,不同土地利用之间土壤容重、全氮、有机碳、速效磷、速效钾的含量差异显著。相比之下 ,农田土壤养分含量偏低 ,而灌丛有着较高的有机碳、总氮与有效氮含量。 0～ 4 0cm土壤碳的储量变化幅度不大。综合土壤退化指数表明 ,坡耕地 ,撂荒地与人工林有土壤退化的趋势 ,而灌丛与次生林对土壤的性质有着改善的作用。人工林年龄与土壤有机碳、有机氮的含量正相关。     

紫色丘陵区水土保持林低效化的土壤成因

四川盆地紫色丘陵区的水土保持林低效化问题已较严重。研究了其土壤方面的成因。通过对土壤构造、土壤肥力特性、土壤结构性评价等研究，指出该区人工林地的土壤构造发育不正常，土壤腐殖质胶体积累量低。土壤结构质量差等林地土壤退化是土壤水土保持功能降低的主要原因。根据研究的初步结果，提出了相应的对策建议。     

不同更新方式对中亚热带森林土壤理化性质的影响

森林的不同更新方式对森林土壤理化性质有重要影响．本研究通过野外调查探讨中亚热带山区杉木人工林和米槠人促更新林2种不同更新方式下林地土壤理化性质的变化特征,并用土壤退化指数定量描述土壤质量变化．结果表明：杉木人工林土壤表层（0—10cm）容重显著高于米槠人促更新林（P〈0．05）;随土壤深度的增加,杉木人工林和米槠人促更新林土壤有机C、全N、全P、水解N和有效P均逐渐降低．米槠人促更新林表层（0—10cm）土壤有机c比杉木人工林高出15．6％,全N、全P以及水解N和速效P也均表现出人促米槠更新林高于杉木人工林的趋势;土壤退化指数的计算结果表明杉木林土壤质量显著低于米槠人促更新林．     

Soil degradation: a global problem endangering sustainable development

1 Introduction Soil is not only the major natural resource on which human being depends for the production of food, feed, fiber, renewable energy and raw materials, but also plays a key role in maintaining the complex terrestrial ecosystems and climate systems of this planet. Recent rapid increase in the human population is placing a great strain on the worlds soil resources. Only about 11% of the global land surface covered by the soils are being used to raise crops and livestock, in other …     

Soil degradation: a global problem endangering sustainable development

Soil degradation, defined as lowering and losing of soil functions, is becoming more and more serious worldwide in recent decades, and poses a threat to agricultural production and terrestrial ecosystem. It is estimated that nearly 2 billion ha of soil resources in the world have been degraded, namely approximately 22% of the total cropland, pasture, forest, and woodland. Globally, soil erosion, chemical deterioration and physical degradation are the important parts amongst various types of soil degradation. As a natural process, soil degradation can be enhanced or dampened by a variety of human activities such as inappropriate agricultural management, overgrazing, deforestation, etc. Degraded soil means less food. As a result of soil degradation, it is estimated that about 11.9-13.4% of the global agricultural supply has been lost in the past five decades. Besides, soil degradation is also associated with off-site problems of sedimentation, climate change, watershed functions, and changes in natural habitats leading to loss of genetic stock and biodiversity. Therefore, it is essential to combat soil degradation at different levels and scales worldwide, not only for food security and ecological health, but also for the guarantee of global sustainable development.     

黑河流域土壤退化研究

在黑河流域干旱土纲中采集5个典型土壤剖面以研究该地区干旱土壤的演化。同时，为了了解土壤养分含量、土壤干旱化和土壤盐化的变化趋势，测定了高台县西北盐池地区主要盐土类型各剖面中的盐分含量和流域内主要土类中水分含量的分布。结果表明，干旱区内陆河流域土壤的退化主要表现为干旱化、盐渍化和土壤肥力的退化。在流域内干旱化随流域上中下游降水量和干燥度的变化而变化，土壤随距河流的距离及地下水位的高低而变化。流域内土壤从潜育土向雏形十、干旱雏形土和干旱土的方向变化。盐渍化与土壤水分含量和地下水位有关，并与水分的蒸发有密切的关系。在一定范围内，距水源越远，盐分含量一般越高。土壤肥力的退化表现为土壤有机质含量降低，阳离子代换量降低等理化性质的退化，这一退化过程是其它过程的综合反映。质地的退化虽受风沙化的影响，但与土壤的形成母质有一定的关系。     

Soil and plant responses to degradation of alpine grassland in source region of the Yellow River

Land degradation has been rapidly taking place in source region of the Yellow River in China. This study was conducted during 2008 in Maduo County to investigate soil and plant changes in relation to land degradation. Several results were derived from this work. First, the soil organic carbon (SOC) and total nitrogen (TN) decreased significantly on the extremely degraded land comparing with the natural grassland. Second, soil bulk density increased as land degradation worsened. Soil bulk density of the extremely degraded land was significantly greater than that of the grassland. Third, pH showed no obvious variation pattern. Finally, aboveground biomass decreased from grassland to the moderately degraded land. But aboveground biomass increased on the extremely degraded land and very extremely degraded land with most aboveground biomass inedible for livestock.     

高寒草甸草地退化对土壤水热性质的影响及其环境效应

青藏高原高寒草甸草地的大面积退化,将改变浅层土壤的水热性质,影响地表水热交换,甚至导致区域生态环境的变化。本文通过系统分析典型原生高寒草甸与中度退化高寒草甸的植物群落特征、地上地下生物量和土壤理化特征的差异,研究高寒草甸草地退化对土壤水热性质的影响及其环境效应。结果表明:随着高寒草甸草地退化,植被覆盖度显著降低(p<0.01),适应旱生、深根系的杂草侵入适应湿润生境、浅根系的以莎草科植物为主的原生植被,生物多样性显著增加(p<0.01);草毡表层(0～10 cm)地下生物量显著减少(p<0.01),30～50 cm地下生物量显著增加(p<0.01)。草毡表层变薄降低了土壤容重的垂向异质性,使表层土壤容重显著增加(p<0.01),土壤颗粒显著变粗(p<0.01)。受浅层土壤有机质降低和土壤容重增加的影响,中度退化高寒草甸土壤的持水量和饱和导水率降低,土壤导热率升高。高寒草甸草地植被退化,土壤持水量、饱和导水率降低和导热率增加将加速地表水热交换,对高寒草甸草地退化和下伏多年冻土消融都可能是正反馈。     

Amplifying (or Reversing) the Territorial Disparities in Land Vulnerability to Soil Degradation: The Case of Italy

This article analyzes the territorial disparities in the level of land vulnerability (TDLV) to soil degradation caused by five processes (soil erosion, salinization, sealing, contamination, and compaction) as well as by climate variations in Italy in 1990 and 2000. The analysis reveals, for each soil degradation process, a typical spatial distribution across Italy. Three processes (soil salinization, compaction, and sealing) contribute significantly to the increase in land vulnerability, which is mainly concentrated in risky areas. The observed disparities highlight a growing environmental divide between northern Italy (an economically developed region, not at risk of desertification) and southern Italy and the two main islands (dry, disadvantaged regions at risk of desertification). The knowledge of such a territorial divide and of the underlying soil degradation processes is regarded as important for environmental policies at the country and regional scales aimed at sustaining the economic and socioenvironmental cohesion between areas that are either vulnerable or nonvulnerable to soil degradation. The proposed approach should be seen as part of a decision-making tool informing policies and supporting the design of management solutions, hopefully reversing disparities in land vulnerability to soil degradation.     

红壤退化中的土壤质量评价指标及评价方法

土壤质量评价与监测是评价土壤退化的重要工作,也是重新设计持续性的土壤管理系统的基础。目前缺乏统一的评价指标以及将各项土壤性质与土壤管理措施结合起来的评价方法。本文首先提出了选择红壤质量评价指标的原则,并从化学、物理学和生物学三个方面初步探讨了评价红壤质量动态变化可资采用的指标体系,综述了国内在南方丘陵区红壤质量演化的研究中应用的指标;最后从土地评价方法中选择了可用于红壤质量评价的方法,并简要综述了国际上最新的土壤质量评价方法。     

岩溶山区不同植被群落土壤生态系统特性研究

自然植被演替成为次生植被、人工林或人工开垦利用后,岩溶山地土壤物理性能退化;沙化现象明显;坡耕地土壤长时间持水供水性能、抗旱性能降低;土壤种子库中草本种子比例大,木本植物种子少,土壤种子库退化更严重。研究区土壤有机质和全N受植被类型和土地利用强度影响明显,坡耕地土壤有机质较林草地系统低,退耕还林还草后,土壤有机质含量稳定增加。与自然植被相比,人工林、次生林系统土壤有机质含量仍较低。从弃耕地→灌草坡→次生林地的演替过程中,土壤种子库生态优势度呈降低趋势,物种丰富度和多样性增加。研究结果认为,岩溶生态系统土地退化的实质是土壤作为水库、养分库和土壤种子库功能的差异退化。