分期打顶对不同密度棉花产量影响初探

通过对棉花不同密度和打顶时期两项栽培措施的试验研究,得出在温宿县于7月21日左右打顶,以分层分批的打顶方式最能获得高产.在中等肥力条件下,6行30万株/hm2比4行20万株/hm2产量高.     

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.     

新疆棉花比较优势的进一步分析:基于经济收益

经统计分析 ,棉花净产值与玉米净产值之比X3对年度皮棉增加率Y2有极显著影响 (p <0 .0 1)、棉花净产值与 (玉米 +小麦 )平均净产值之比X4、棉花减税纯收益与玉米减税纯收益之比X6、棉花减税纯收益与 (玉米+小麦 )平均减税纯收益之比X7对年度皮棉增加率Y2有显著影响 (p <0 .0 5 )。新疆中绒棉的X3介于山东和安徽之间 ,X4处于较高水平 ,X6比山东、安徽分别高 0 .8和 0 .3或 73%和 19%,X7比山东、安徽分别高 1.1和 0 .2或 92 %和 10 %,可见新疆中绒棉的种植优势是存在的。新疆长绒棉的优势更大 ,以上 4个指标比山东、安徽二省均值高 2 6 %～ 10 0 %。这些指标的增加 ,对年度皮棉增加率的贡献是明显的。按回归分析 ,X3、X4、X6、X7每增加 1,分别意味着当地皮棉比上年度有增加 33.9%、36 .8%、16 .8%、12 .7%的趋势。     

作物气候风险研究:以河南省棉花为例

1 Introduction In the past 100 years the global temperature rose sharply due to the increase of greenhouse gas emissions into the atmosphere. The mean ground temperature rose by 0.5–0.6°C in the 20th century and 0.3–0.4°C in the last 20 years of the c…     

四川植棉紫色土养分对棉花营养和纤维品质的影响

在分析植棉紫色土养分对棉花营养影响的基础上,讨论了土壤养分对棉花纤维品质的作用.比强度、2.5％跨距长度、伸长度、麦克隆值和整齐度五个纤维品质指标中,前三者与土壤养分显著相关.土壤养分中对纤维品质影响较大的是微量元素硼、铜及大量元素磷、钾,其中以硼和铜与棉花纤维品质的关系最为密切.     

棉纤维生长各阶段的土壤水分状况对其束强的影响

在纤维伸长前期、填充后期充足的土壤水分对提高束强有利，纤维生长扭曲期土壤干旱对提高束强有利，反之则不利。     

应用Cotton2k模型模拟北疆棉花生长结果的分析

Cotton2k模拟模型是一个动态模型,能在生理过程水平上模拟棉花的生长发育和产量形成。通过应用棉花生产管理系统(GOSSYM/COMAY)中一种机理性很强的棉花生长模拟模型Cotton2k,对新疆北部地区棉花的生长状况进行模拟。从生育期的模拟结果分析得出除60%吐絮期误差较大外,其他生育期的模拟结果非常好;从形态发育模拟和实测结果比较表明:形态发育在花铃期前基本吻合;各器官干物质重的模拟和实测结果比较表明:除叶重误差较大外,其他的模拟结果较为满意,特别是植株干重的模拟可以作为精准农业水肥诊断的依据;植株中氮浓度的模拟误差较大,其原因分析有二:(1)棉花在生长发育过程中本身的生物学特性决定了每个生育期对不同肥的吸收量值不同,导致模拟值与观测值有差异;(2)在播种前应对试验地的肥力进行测定,使原始含N量的差异排除,会对模拟结果的精度有所提高。各层土壤含水量的模拟结果表明:耕作层0~45的土壤水分含量差异较大,但是45 cm以下土层的土壤含水量模拟结果与实测值基本吻合;不同水肥处理方式下的产量模拟结果和实测结果比较,产量模拟的误差较大。     

阿克苏市地膜棉播期气象年型模糊聚类分析

应用模糊聚类方法，对阿克苏市当前棉花生产水平下地膜棉播期气象年型进行分类。在此基础上提出了相应的气象服务对策。     

抗虫棉早衰气象条件分析与防御对策

利用山东省惠民县气象局1988～2007年(抗虫棉1998～2007年,常规棉1988～1997年)观测资料,对温度和降水影响棉花早衰问题进行了分析,得出5～7月平均气温和秋桃数呈明显负相关关系,5～7月平均气温越高,秋桃数越少,棉花早衰越严重;6月中旬至7月中旬降水偏少,干旱易形成老小苗,棉花发生早衰;8月中旬至9月上旬降水偏少、秋桃偏少,造成棉花早衰。从气象方面提出了抗虫棉早衰的防御对策。     

酒泉市棉花病虫害发生规律与气象条件的初步分析

利用敦煌、安西、金塔三地气象和病虫害资料,应用农业气象中的统计方法,分析了棉花病虫繁殖危害与气象条件的关系。结论是：影响棉花产量及品质的主要虫害是棉蚜、棉铃虫、棉红蜘蛛;影响虫害繁殖的主要气象因子是温度、湿度、降水等。可以通过采取生态措施和工程措施改善病虫害对棉花的威胁程度。