科尔沁沙地草地植被对围封和放牧的响应

研究了科尔沁沙地疏林草地、针茅草原和草甸植被盖度、地上和地下生物量、物种多样性对围封和放牧的响应。结果表明：（1）围封与放牧草地的优势植物不同,围封草地植物群落优势植物为多年生禾本科植物,放牧草地中一年生植物和小半灌木优势明显。（2）围封和放牧草地的植物盖度、凋落物量、地上生物量和物种丰富度存在明显差异（P<0.05）;围封显著提高了植被盖度和地上生物量,由疏林草地、针茅草原到草甸,植物盖度和地上生物量逐渐增加,而3种草地植被凋落物量大小顺序为针茅草原> 疏林草地> 草甸;放牧条件下植物盖度、凋落物量和物种丰富度差异不显著（P>0.05）。（3）3种草地之间的地下生物量无显著差异（P>0.05）,但围封与放牧之间、不同土壤层次之间地下生物量存在明显差异（P<0.05）;围封显著提高草地的地下生物量（P<0.05）;草地地下生物量随着土壤深度表现出下降趋势（P<0.05）。长期放牧增加了草地一年生植物和小半灌木植物的优势,消除了不同草地之间植被盖度和物种丰富度的差异;而围封能提高草地多年生禾本科植物的优势、增加其物种丰富度,对于草地质量和植物多样性的恢复和保育具有积极作用。     

岷江干旱河谷豆科植物多样性及其空间格局

为研究岷江干旱河谷的豆科植物物种多样性及其在纬度和海拔梯度上的分布格局,在从四川汶川到松潘的干旱河谷两岸选择了7个地点,通过204个样方 (2 m×2 m) 调查,分析了不同纬度和海拔豆科物种组成、高度、盖度与根系结瘤的空间分布特点.结果表明:(1) 在所有样方中共出现乡土豆科植物16属,38种,其中灌木7属19种;草本植物7属17种,1或2 a生草本 6种,多年生草本11种.仅刺槐 (Robinia pseudoacacia L.) 和葫芦巴 (Trigonellae foenum-graecum L.) 为栽培物种.灌木在该地区豆科植物中占较大优势,50%以上灌木的频度与盖度均＞10%,尤其白刺花 (Sophora davidii)、小马鞍羊蹄甲 (Bauhinia brachycarpa var.microphylla)、岷谷木蓝 (Indigofera lenticellata) 等灌木频度＞20%,而所有草本植物的频率及盖度都＜10%. (2) 豆科植物丰富度及生长具有较为明显的空间差异,干旱河谷核心地区的干热、贫瘠环境中,总物种丰富度较高,但是其盖度与高度较小.随着纬度升高,灌木丰富度和频度均减少,草本丰富度与和频度增加.随着海拔上升,灌木丰富度与总物种丰富度都减小,草本植物丰富度变化不明显;植物平均高度与盖度高度也无明显的垂直变化规律.(3) 植物根系结瘤能力很低,66%物种未结瘤,并且幼苗结瘤能力显著大于成株.这一结果可为豆科植物资源的保护和开发利用提供科学依据.     

放牧强度对科尔沁沙地沙质草地植被的影响

为了研究科尔沁沙地沙质草地在不同放牧强度下植被特征的变化规律,比较了围封、中度放牧、重度放牧3种条件下的植被盖度、群落组成、物种多样性、地上/地下生物量和凋落物量等植被特征的变化特征。结果表明:(1)围封、中度放牧和重度放牧沙质草地的优势植物均为一年生植物,但围封和中度放牧中多年生禾本科植物优势度高于重度放牧,重度放牧沙质草地一年生植物所占优势度最大;(2)放牧强度对沙质草地植被盖度、地上生物量及凋落物量有显著影响。随着放牧强度的增加,植被盖度、地上生物量和凋落物量均降低;(3)围封、中度放牧和重度放牧沙质草地物种丰富度及多样性差异均不显著;(4)放牧强度和土壤深度及其交互作用均能影响地下生物量。随着放牧强度的增加,总的地下根系生物量减小。而重度放牧草地中, 3个土壤深度间地下根系生物量差异不显著。放牧改变了沙质草地植物群落的组成、极大降低了植被盖度和生产力;尤其是重度放牧急剧增加了一年生植物的优势、且对浅层根分布的减少影响最大。     

放牧对浑善达克沙地丘间低地植被群落及土壤的影响

为探究放牧对丘间低地植被群落及土壤的影响，分析了浑善达克沙地丘间低地在重度和轻度放牧下植被的地上生物量、物种重要值、物种丰富度、Shannon-Wiener多样性指数、Pielou均匀度指数、Simpson生态优势度指数及0~10 cm土壤中黏粒、粉粒、砂粒、有机碳和全氮含量。结果表明：（1）植被地上生物量、土壤黏粒、粉粒、砂粒、土壤有机碳和全氮含量在不同放牧程度下存在极显著差异（P<0.01），物种丰富度、Shannon-Wiener多样性指数和Pielou均匀度指数在不同放牧程度下差异不显著（P>0.05），Simpson生态优势度指数在不同放牧程度下差异显著（P<0.05）。（2）放牧区植被以禾本科为主，禾本科植被地上生物量占整个植被群落的54.88%~57.76%；重度放牧区植被地上生物量为63.59 g·m^-2，比轻度放牧区低26.61%。（3）羊草（Leymus chinensis）和狗尾草（Setaria viridis）是放牧区的优势种，其重要值依次为14.16%（重度放牧区）和19.10%（轻度放牧区）、13.40%（重度放牧区）和15.42%（轻度放牧区），重度放牧下雾滨藜（Bassia dasyphylla）、克氏针茅（Stipa krylovii）和猪毛蒿（Artemisia scoparia）的重要值较显著高于轻度放牧区，而羊草则低于轻度放牧区。（4）重度放牧加剧了土壤沙漠化，使砂粒含量增加，草地生产力下降，土壤有机碳和全氮含量降低。     

基于植被盖度和高度的不同退化程度高寒草地地上生物量估算

由于气候变化和不合理的人类活动，20世纪80年代以来青藏高原高寒草地发生严重退化。地上生物量是评价草地退化的直观指标。通常采用植被盖度和高度来估算草地地上生物量，但草地退化后，植被盖度和高度与地上生物量之间的关系是否会发生变化目前还不清楚，这影响着退化草地生物量估算的精度。通过多元回归分析研究了青藏高原中部和东北部高寒草甸、高寒草原在不同退化程度下植被盖度和高度与地上生物量的关系。结果表明：（1）高寒草甸与高寒草原地上生物量整体上及不同退化阶段都没有显著差异（P>0.05）。（2）随着退化程度的加剧植被盖度和高度对地上生物量的影响也发生改变，体现在未退化阶段地上生物量主要受植被高度影响，退化后主要受植被盖度影响。（3）无论是高寒草甸还是高寒草原分退化程度的回归模型估算结果都较不分退化程度模型估算的生物量更接近实测值。我们建议在退化高寒草地研究中采用盖度和高度估算生物量时，根据退化阶段采用不同的估算模型。     

沙质草地放牧和封育下物种丰富度和生物量关系的季节变化

研究了科尔沁沙质草地放牧和封育下植被盖度、密度、丰富度与地上生物量关系的季节变化。结果表明:放牧和封育草地4月的植被盖度、丰富度和生物量均低于生长旺季8月,而4月植物密度要高于8月;封育草地生长季盖度高于放牧草地,6月和8月生物量高于放牧草地, 4月和6月植物密度则低于放牧草地。封育草地8月物种丰富度与生物量呈极显著的负线性关系（p<0.01）;放牧草地植物密度与生物量4月表现出极显著的正线性关系（p<0.01）、8月为极显著的负线性关系（p<0.01）。放牧草地优势植物糙隐子草4月的密度和生物量呈极显著的正线性关系（p<0.01）、8月为极显著的负线性关系（p<0.01）;黄蒿和狗尾草8月的密度和生物量均呈极显著的负线性关系（p<0.01）;猪毛菜4月和6月的密度和生物量呈极显著的正线性关系（p<0.01）。封育草地达乌里胡枝子、猪毛菜8月的植物密度和生物量呈极显著的正线性关系（p<0.01）。持续放牧和季节变化及其二者的交互作用对植被盖度、密度和生物量均有重要的影响（p<0.05）;放牧通过影响草地生长季中的优势植物密度变化和生物量积累,引起了草地植物密度和生物量关系的季节变化,也导致生长季物种丰富度和生物量无显著关系;封育草地植物的竞争导致了物种丰富度和生物量关系的季节变化。     

科尔沁沙地沙质草地与固定沙丘植物群落结构对极端干旱的响应

为了探究沙地植物群落结构特征对极端干旱的响应,通过野外模拟试验开展了极端干旱（生长季减雨60%与干旱60 d）对沙质草地和固定沙丘植物群落丰富度、地上生物量和叶性状等群落结构特征影响的研究。结果表明：（1）生境变化对植物群落地上生物量和叶干物质含量（LDMC）具有显著影响（P<0.05）,草地地上生物量和LDMC显著高于固定沙丘,而物种数、植被盖度、高度和比叶面积（SLA）在两种生境间无显著差异（P>0.05）;（2）极端干旱处理显著影响沙地植物群落盖度、地上生物量和LDMC（P<0.05）,减雨60%显著降低了植物群落盖度和地上生物量,而干旱60 d显著降低了植物群落盖度、地上生物量、高度和LDMC;植被特征和叶性状在减雨60%和干旱60 d处理间无显著差异（P>0.05）;（3）减雨60%和干旱60 d显著降低了草地和固定沙丘的植被盖度和地上生物量,而干旱60 d也降低了固定沙丘的植物高度和LDMC（P<0.05）;（4）相关分析表明,沙地植物群落地上生物量与盖度、高度和LDMC显著正相关（P<0.05）。极端干旱事件的发生会极大地改变沙地一年生为主的植物群落组成和功能,而沙地不同生境植被则通过改变植物群落组成、优势种及其关键性状的变化来适应极端干旱。     

藏北高山嵩草草旬植被和多样性在沙漠化过程中的变化

为确定沙漠化对高山嵩草草甸植被组成、结构和物种多样性的影响，了解高寒区草甸沙漠化的原因，选择西藏那曲安多县南部沙漠化严重区域为调查区，按照沙漠化的不同程度设置样地，系统调查了轻度、中度、重度和极重度沙化草甸的植被变化，结果表明：中度、重度和极重度沙化区的植被与轻度沙化草甸有显著的差异；在中度和重度沙化区，高寒草甸的建群种高山嵩草已被家畜不喜食或更具抗性的植物种所取代，而在极重度沙化的流动沙丘上无植被生长；从过牧的退化草甸到半流动、流动沙丘，植物种多样性呈显著的降低趋势。轻度沙化草甸物种数、个体密度和丰富度指数最多；中度沙化草甸的Shannon-Wiener指数和均匀度指数最大，而优势度指数最小；在沙化过程中，高寒草甸的植被盖度显著下降，地上生物量也在下降，虽然轻度、中度和重度沙化草地的地上生物量显著高于极重度沙化区，但前者之间却无显著差异。地下根系生物量也呈显著下降的趋势。过牧是造成高山嵩草草甸沙化的主要原因。     

莫莫格湿地恢复区的植物群落物种多样性研究

植物群落多样性水平能够指示退化湿地修复的效果。在莫莫格国家级自然保护区综合恢复示范区,采用调查样线与样方相结合的调查方法,开展植物群落野外调查,比较了退化湿地修复前、后植物群落物种组成的差异,探讨了恢复水文条件和地貌修复对植物群落物种多样性的影响。研究结果表明,在综合恢复示范区内,共记录12科22属38种植物,其中,一年生和多年生植物都为19种,禾本科(Gramineae)、藜科(Chenopodiaceae)和蓼科(Polygonaceae)物种数量之和占记录的总物种数量的60.53%;芦苇(Phragmites australis)群落和辽宁碱蓬(Suaeda liaotungensis)群落是该区的优势植物群落,植物群落中的优势种多为耐盐碱类植物;从调查样带1至调查样带4,即由陆地向湖泊方向,植物群落的物种丰富度、Simpson优势度指数、Shannon-Wiener多样性指数都在不断增大;水文-植被-微地貌系统修复模式可以作为松嫩平原西部退化盐碱湿地修复的优选模式。     

西藏沙漠化典型分布区沙漠化过程中的生物生产力和物种多样性变化

阿里地区狮泉河谷、日喀则江当河谷阶地和安多错那湖东侧是西藏自治区沙漠化土地分布比较集中的3个典型区,并代表了西藏高原3个不同的生物气候带。为确定沙漠化对植被生产力和物种多样性的影响,选择这3个典型区内代表沙漠化发展过程的不同地貌类型为调查样地。结果表明:沙漠化造成3个典型区植被盖度显著降低,尤其从潜在沙漠化土地到固定沙丘或半固定沙丘,植被盖度下降幅度最大;3个典型区的现存生物量同样随着沙漠化过程显著降低。同时,沙漠化造成狮泉河谷和江当河谷阶地多年生灌木物种消失,流动沙丘仅有少数一年生植物分布;沙漠化造成原有物种的数量和分布发生变化,尤其在固定沙丘逐渐活化,形成流动沙丘的过程中,丰富度指数显著下降。3个典型区的Shannon-Wiener指数在沙漠化前期和后期表现不同,但从固定沙丘至半流动沙丘均为显著性下降趋势。总体而言,从潜在沙漠化土地到流动沙丘,Shannon-Wiener指数显著降低。     

BOOK REVIEWS

Book Reviewed in this article: Development and Environment in Peninsular Malaysia . S. Robert Aiken, Colin H. Leigh, Thomas R. Leinbach, Michael R. Moss. The Rural-Urban Fringe: Canadian Perspectives . Ken B. Beesley and Lorne H. Russwurm, eds. Women and Development . Lourdes Benería, ed. The Border that Joins: Mexican Migrants and U.S. Responsibility . Peter G. Brown and Henry Shue, eds. Cities of the World: World Regional Urban Development . Stanley D. Brunn and Jack L. Williams, eds. Time Resources, Society, and Ecology: On the Capacity for Human Interaction in Space and Time (Vol. I, Preindustrial Societies). Tommy Carlstein. Urban Geography . David Clark. Spanish City Planning in North America . Dora P. Crouch, Daniel J. Garr, and Axel I. Mundigo. Not On Our Street: Community Attitudes to Mental Health Care . M. J. Dear and S. M. Taylor Unequal growth: Urban and Regional Employment Change in the U.K. Stephen Fothergill and Graham Gudgin. Agricultural Land in an Urban Society . Owen J. Furuseth and John T. Pierce. The Petroleum Industry in Oil-Importing Developing Countries . Fariborz Ghadar. Historical Understanding in Geography, An Idealist Approach . Leonard Guelke. Regional Planning in Europe . R. Hudson and J. R. Lewis, eds. Remote Sensing for Resource Management . Chris J. Johannsen and James L. Sanders, eds. Geography and The State . R. J. Johnston. Texas Graveyards: a Cultural Legacy . Tlrry G. Jordan. The Politics of Location: An Introduction . Andrew Kirby. A Social Geography of the City . David Ley. Energy and the Future . Douglas MacLean and Peter Brown, eds. The Natural Environment of Newfoundland Past and Present . A. G. Macpherson and J. B. Macpherson, eds. Tourism: Economic, Physical and Social Impacts . Alister Mathieson and Geoffrey Wall. Railroads and Land Grant Policy: A Study in Government Intervention . Lloyd J. Mercer. Progress in Rural Geography . Michael Pacione, ed. Progress in Urban Geography . Michael Pacione, ed. Models of Spatial Inequality: Settlement Patterns in Historical Archaeology . Robert Paynter. Natural Hazard Risk Assessment and Public Policy, Anticipating the Unexpected . William J. Petak and Arthur A. Atkisson. The Nature of Geomorphology . Alistair F. Pitty. Regional Conflict and National Policy . Kent A. Price Women and Spatial Change: Learning Resources for Social Science Courses . Arlene C. Rengert and Janice J. Monk, eds. Urban and Regional Analysis for Development Planning . Richard Rhoda. Rivers: Form and Process in Alluvial Channels . Keith Richards. This Remarkable Continent: An Atlas of United States and Canadian Society and Culture . John F. Rooney, Jr., Wilbur Zelinsky, and Dean R. Louder, gen. eds. The Origins of Open-Field Agriculture . Trevor Rowley, ed. Residential Location Determinants of the Older Population . Gundars Rudzitis. Borderland Sourcebook: A Guide to the Literature on Northern Mexico and the American Southwest . Ellwyn R. Stoddard, Richard L. Nostrand, and Jonathan P. West, eds. Arctic and Antarctic . David Sugden. Tall Timbers Ecology and Management Conference, February 22–24, 1979, Proceedings No. 16 . Graphic Communication and Design in Contemporary Cartography (Progress in Contemporary Cartography , Vol. II). D. R. Fraser Taylor, ed. Living with Energy Shortfall: A Future for American Towns and Cities . Jon Van Til. The United States: Habitation of Hope . J. Wreford Watson. Air Photo Interpretation for Archaeologists . D. R. Wilson. Urban and Rural Change in West Germany . Trevor Wild, ed. Population and Resources . Harry Robinson.     

BOOK REVIEWS

Book Reviewed in this article: Geography and the Third World. International Seminar, 14–18 May 1980, Kuala Lumpur, Malaysia . Ishmail Ahmad and Jamaluddin Md Jahi, eds. The Growth Dilemma: Residents' Views and Local Population Change in the United States . Mark Baldassare. Sport and Place: A Geography of Sport in England, Scotland & Wales . John Bale. The Deindustrialization of America: Plant Closings, Community Abandonment, and the Dismantling of Basic Industry . Barry Bluestone and Bennett Harrison. Selected Essays 1963–1975: Carl O. Sauer . Bob Callahen, ed. Housing and Planning in the Countryside . G. Clark. Conflict, Politics and the Urban Scene . Kevin R. Cox and R. J. Johnston, eds. Thematic Maps: Their Design and Production . David J. Cuff and Mark T. Mattson. Wine: A Geographic Appreciation . Harm Jan de Blij. USSR in Maps . J. C. Dewdney. Political Geography: A Contemporary Perspective . Ramesh D. Dikshit. Rethinking Human Adaptation . Rada Dyson-Hudson and Michael A. Little, eds. Sacred Sands: The Struggle for Community in the indiana Dunes . J. Ronald Engel. Geography of the Biosphere . A. Furley and Walter W. Newey. Disaster and Reconstruction . Robert Geipel. Glasgow: The Making of a City . Andrew Gibb. Design for Arid Regions . Giden S. Golany, ed. Urbanization and Cancer Mortality: The United States Experience, 1950–1975 . Michael R. Greenberg. Geology in the Nineteenth Century: Changing Views of a Changing World . Mott T. Greene. Colonización y Destrucción de Bosques en Panamá . Stanley Heckadon Moreno and Alberto McKay, eds. Urban Geography: A First Approach . David T. Herbert and Colin J. Thomas. The Visual and Spatial Structure of Landscapes . Tadahiko Higuchi. Climate from Tree Rings . M. K. Hughes, P. M. Kelly, J. R. Pilcher, and V. C. LaMarche, Jr., eds. The structure of Nineteenth Century Cities . James H. Johnson and Colin G. Pooley, eds. The American Planner: Biographies and Recollections . Donald A. Krueckeberg, ed. Urban Land Policy For the 1980s, the Message for State and Local Government . George Lefcoe, ed. Regional Planning: Evolution, Crisis and Prospects . Gill C. Lim, ed. Relevance and Ethics In Geography . Bruce Mitchell and Dianne Draper. China: The Geography of Development and Modernization . Clifton W. Pannell and Laurence J. C. MA. The Urban Retailing System . Robert B. Potter. Hants. Nonconventional Energy Resources . Philip R. Pryde. Caribbean Migrants: Environment and Human Survival on St. Kitts and Nevis . Bonham C. Richardson. Population and Resources . Harry Robinson. East Los Angeles: History of A Barrio . Ricardo Romo. Integrated Impact Assessment . Frederick A. Rossini and Alan L. Porter, eds. Environmental Aesthetics: Essays in Interpretation . Barry Sadler and Allen Carlson, eds. Earthwatch . Charles Sheffield. Field Techniques and Research Methods in Geography . Robert H. Stoddard. Haiti: Land of Poverty . Robert J. Tata. Weathering and Erosion: Sources and Methods in Geography . Stephen T. Trudgill. Once Beneath the Forest. Prehistoric Terracing in the Río Bec Region of the Maya Lowlands . B. L. Turner, II. The Historical Geography of Scotland since 1707 . David Turnock.     

PRODUCTIVITY OF AMERICAN PH.D.-GRANTING DEPARTMENTS OF GEOGRAPHY

Reviews of geographic software in this article:

DEMO-GRAPHICS: WORLD POPULATIONS AND PROJECTIONS.

ESP

GAUSS.

CEMODEL S. Damus

LIMDEP. William H. Greene

MICROSTAT 4.1

OTIS

PCIPS. (Personal Computer Image Processing System). H.J. Meyers and R. Bernstein.

REGRESSION ANALYSIS OF TIME SERIES (RATS)

SPSS/PC+

URBAN DATA MANAGEMENT SOFTWARE (UDMS)     

Journal of Resources and Ecology Total Contents of Volume 5, 2014

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BOOK REVIEWS

Book Reviewed in this article: Rabat: Urban Apartheid in Morocco . Janet Abu -Lughod . Marketplaces in a Developing Country: The Case of Western Nigeria . Isaac Ayinde Adalemo . Farming Development and Space: A World Agricultural Geography . Bernd Andreae . Section and Party: A Political Geography of American Presidential Elections, from Andrew Jackson to Ronald Reagan . J. Clark Archer and Peter J. Taylor . Women and Space: Ground Rules and Social Maps . Shirley Ardener , ed. European Progress in Spatial Analysis . R. J. Bennett , ed. The Origins of Academic Geography in the United States . Brian W. Blouet Geographic Perspectives on Global Problems . Ronald Reed Boyce . Seasonal Dimensions to Rural Poverty . Robert Chambers , Richard Longhurst and Arnold Pacey eds. The New Nationalism and the Use of Common Spaces: Issues in Marine Pollution and the Exploitation of Antarctica . Jonathan I. Charney , ed. Communications Tomorrow: The Coming of the Information Society . Edward Cornish , ed. The Design of Suburbia . Arthur Edwards . Explorer on the Northern Plains: Lieutenant Gouverneur K. Warren's Preliminary Report of Explorations in Nebraska and Dakota in the Years 1855–56–57. With an Introduction by Frank N. Schubert . The Changing Climate: Responses of the Natural Flora and Fauna . Michael J. Ford . Essentials of Physical Geography . Robert E. Gabler , Robert J. Sager , Sheila Brazier , and Daniel L. Wise. The Road to Jaramillo . William Glen . Valued Environments . John R. Gold and Jacquelin Burgess , eds. Proximity and Preference: Problems in the Multidimensional Analysis of Large Data Sets . Reginald G. Golledge and John N. Rayner , eds. A Search for Common Ground . Peter Gould and Gunnar Olsson , eds. Geography: Its History and Concepts . Arild Holt -Jensen . A Population Geography . Huw R. Jones . The Human Mosaic: A Thematic Introduction to Cultural Geography, 3rd ed. Terry G. Jordan and Lester Rowntree . Urban Social Geography: An Introduction . Paul Knox . The Anatomy of Job Loss: The How, Why and Where of Employment Decline . Doreen Massey and Richard Meegan . The Information Society as Post-Industial Society . Yoneji Masuda . Map Librarianship, 2nd ed. Harold Nichols . India: Cultural Patterns and Processes . Allen G. Noble and Ashok K. Dutt , eds. The God that Limps: Science and Technology in the Eighties . Colin Norman . Geography: An Introductory Perspective . Robert E. Norris , Keith D. Harries and John D. Vitek . The Politics of Technology Assessment . David M. O'Brien and Donald A. Marchand . Ethnic Segregation in Cities . Ceri Peach , Vaughan Robinson and Susan Smith , eds. Churches and Church Membership in the United States, 1980 . Bernard Quinn , Herman Anderson , Martin Bradley , Paul Goetting and Peggy Shriver . Energy in Australia: Politics and Economics . Hugh Saddler . Development from Above or Below? The Dialectics of Regional Planning in Developing Countries . Walter B. Stóuhr and D. R. Fraser Taylor , eds. Human Impact on the Ecosystem . Joy Tivy and Greg O'Hare . Plants and People: Vegetation Change in North America . Thomas R. Vale . The Mapmakers: The Story of the Great Pioneers in Cartography from Antiquity to the Space Age . John Noble Wilford .     

Deserts and Aeolian Desertification in China: Book review and some thoughts

Desertification is a global phenomenon that affects about two billion people. It occurs in arid zones where the annual precipitation is below 400 mm, partic- ularly in the marginal areas of the world＇s largest deserts. It is a result of water and wind erosion, over- grazing, global warm-ing, improper soil cultivation, and increased pressure ot population growth, and it causes degradation of soil and natural and agricultural vegetation. The direct result is less food for people and livestock, which influences pop- ulation and animal husbandry fluctuations. Despite ef- forts to combat and reduce desertification, the affected areas are annually increasing.     

BOOK REVIEWS

Book Reviewed in this article: The Rice Economy of Asia . Randolph Barker and Robert W. Herdt with Beth Rose. Using Microcomputers: A Guidebook for Writers, Teachers, and Researchers in the Social Sciences . Blaine A. Erie—the Lake that Survived . Noel M. Burns. Geology and Society . Donald R. Coates. Caves and Karst of Kentucky . Percy H. Dougherty, ed. Altered Harvest: Agriculture, Genetics, and the Fate of the World's Food Supply . Jack Doyle. The Middle East and North Africa, A Political Geography . Alasdair Drysdale and Gerald H. Blake. Clamor at the Gates. The New American Immigration . Nathan Glazer, ed. Development and the Landowner: An analysis of the British experience . Robin Goodchild and Richard Munton. Discovering Landscape in England and Wales . Andrew Goudie and Rita Gardner. The Modern Plantation in the Third World . Edgar Graham and Ingrid Floering. Social Relations and Spatial Structures . Derek Gregory and John Urry, eds. The World Food Problem 1950–1980 . David Grigg. Costa Rica: A Geographical Interpretation in Historical Perspective . Carolyn Hall. The Urbanization of Capital: Studies in the History and Theory of Capitalist Urbanization . David Harvey Consciousness and the Urban Experience: Studies in the History and Theory of Capitalist Urbanization . David Harvey. Reviving Main Street . Deryck Holdsworth, ed. Rural Roads and Poverty Alleviation . John Howe and Peter Richards, eds. Uneven Development in Southern Europe: Studies of Accumulation, Class, Migration and the State . Ray Hudson and Jim Lewis, eds. Karst Geomorphology . J. N. Jennings. The Geomorphology of North-west England . R. H. Johnson, ed. Climate Impact Assessment: Studies of the Interaction of Climate and Society . Robert Kates, Jesse Ausubel, Mimi Berberian, eds. Public Service Provision and Urban Development . Andrew Kirby, Paul Knox, and Steven Pinch, ed. State and Market: The Politics of the Public and the Private . Jan-Erik Lane, ed. Living Cities . Twentieth Century Fund Task Force on Urban Preservation Policies. World Climatic Systems . John G. Lockwood. Urban Ethnicity in the United States. New Immigrants and Old Minorities . Lionel Maldonaldo and Joan Moore, eds. Culture and Conservation: The Human Dimension in Environmental Planning . Jeffrey A. McNeely and David Pitt, eds. The Andean Past. Land, Societies, and Conflicts . Magnus Mörner. Gaia: An Atlas of Planet Management . Norman Myers, ed. Progress in Industrial Geography . Michael Pacione, ed. Progress in Political Geography . Michael Pacione, ed. Rivers and Landscape . Geoff Petts and Ian Foster. Urbanization and Planning in the 3rd World: Spatial Perceptions and Public Participation . Robert B. Potter. One Island, Two Nations? A Political Geographical Analysis of the National Conflict in Ireland . D. G. Pringle. Circulation in Third World Countries . R. Mansell Prothero and Murray Chapman. The Ozarks Outdoors: A Guide for Fishermen, Hunters, and Tourists . Milton D. Rafferty. Suburban Burglary: A Time and a Place for Everything . George Rengert and John Wasilchick. Geomorphology and Soils . K.S. Richards, R.R. Arnett, and S. Ellis, eds. The Homes and Homeless of Post-War Britain . Frederick Shaw. Indochinese Refugees in America . Paul J. Strand and Woodrow Jones, Jr. Wild Horses and Sacred Cows . Richard Symanski. Forever Wild: Environmental Aesthetics and the Adirondack Forest Preserve . Philip G. Terrie. The Regional Economic Impact of Technological Change . A.T. Thwaites and R.P. Oakey, eds. The Good Life . Yi-Fu Tuan.     

REVIEWS OF GEOGRAPHIC SOFTWARE

Reviews of geographic software in this article: DEMO-GRAPHICS: WORLD POPULATIONS AND PROJECTIONS. ESP GAUSS. CEMODEL S. Damus LIMDEP. William H. Greene MICROSTAT 4.1 OTIS PCIPS. (Personal Computer Image Processing System) . H.J. Meyers and R. Bernstein. REGRESSION ANALYSIS OF TIME SERIES (RATS) SPSS/PC+ URBAN DATA MANAGEMENT SOFTWARE (UDMS)