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1.
为筛选马铃薯(Solanum tuberosum)各发育阶段适宜的灌溉量,使用遮雨棚和智能控水设施进行严格的灌溉量控制,测定了不同发育阶段不同灌溉量(分别为0.5W、0.75W、W、1.25W、1.5W,W为当地维持25.8%土壤含水率的常用灌溉量)下的马铃薯叶片光合生理指标、根系生理指标、植株农艺性状和干物质积累指标。结果表明:1,5-二磷酸核酮糖羧化酶(RuBP羧化酶)活性在结薯期最高、成熟期最低,在发棵期和结薯期对灌溉量响应差异最显著,在W和1.25W下最高。幼苗期叶片净光合速率(P_n)对灌溉量响应不显著,在发棵期、结薯期和成熟期分别以W、1.25W、0.75W下最高。幼苗期、发棵期、结薯期和成熟期根冠比分别在0.75W、0.5W、0.75W、W下最高。幼苗期0.5W延缓了植株的伸长生长,成熟期灌溉量增加有效促进了植株株高的增长,1.5W下植株最高。地上部分干重在幼苗期、发棵期、结薯期分别在W、1.25W、1.5W下最高,成熟期地上部分干重对灌溉量响应不显著。薯重在幼苗期、发棵期、结薯期、成熟期分别在0.75W、W、1.25W、0.75W下最高。  相似文献   

2.
Based on observational data of arid, semi-arid and semi-humid areas in Northwest China, the characteristics of surface-water heat transfer and land-surface parameters were compared and analyzed. The results show that the annual mean net radiation was largest in the semi-humid area, followed by the semi-arid area, and then the arid area: 77.72 W/m~2, 67.73 W/m~2,and 55.47 W/m~2, respectively. The annual mean sensible heat flux was largest in the arid area, followed by the semi-arid and semi-humid areas, while latent heat flux showed the reverse. The annual mean sensible heat flux in arid, semi-arid,and semi-humid areas was 85.7 W/m~2, 37.59 W/m~2, and 27.55 W/m~2, respectively. The annual mean latent heat flux was 0 W/m~2, 26.08 W/m~2, and 51.19 W/m~2, respectively. The annual mean soil-heat flux at the 5-cm soil layer in arid, semi-arid,and semi-humid areas was 1.00 W/m~2, 0.82 W/m~2, and-1.25 W/m~2, respectively. The annual mean surface albedo was largest in the arid area, followed by the semi-humid area; and the smallest was in the semi-arid area: 0.24, 0.21, and 0.18, respectively. The annual mean Bowen ratio in the semi-arid area was about 2.06, and that in semi-humid area was about -0.03.The annual mean soil thermal conductivity in the arid, semi-arid, and semi-humid areas was 0.26 W/(m?k), 1.15 W/(m?k),and 1.20 W/(m?k), respectively.  相似文献   

3.
于2007年和2014年的丰水期和枯水期分别测量了南沙红树林湿地公园一期、二期及其附近河涌8个采样点的水体温度、pH、DO、COD、BOD5、TP和TN等物化指标。通过对比监测结果和倍斜率聚类评价结果发现:研究区水质总体上处于-Ⅲ级或-Ⅳ级的“尚清洁”状态;红树林湿地公园一期2008年对外开放后至2014年,水环境指标中pH变化范围不大,DO、COD含量有所下降,BOD5、TP和TN含量均呈增加趋势;2007年南沙红树林湿地公园一期采样点W1、W2、W3水质优于河涌采样点W7和W8,河涌采样点W7和W8水质优于红树林湿地公园二期采样点W4、W5、W6;2014年南沙红树林湿地公园二期采样点W4、W5、W6水质优于红树林湿地公园一期采样点W1、W2、W3和河涌采样点W7、W8;8个采样点中水质改善最明显的是二期采样点W6,水质下降最明显的是一期采样点W3;丰水期河涌水质2014年较2007年有所好转,但红树林湿地公园水质无论枯水期亦或丰水期,多数情况下优于河涌水质;研究区域水环境质量的时空差异总规律为2007~2014年南沙红树林湿地公园二期水质好转,一期水质有所下降。  相似文献   

4.
论文利用2017年东疆哈密地区红柳河黑戈壁地面高精度紫外辐射实测数据与美国NASA Langely研究中心大气科学数据中心提供的CERES_SYN1 deg_Ed4A产品数据,对卫星反演的紫外辐射A、B波段(UVA和UVB)数据在该地区的适用性进行了对比验证。结果表明:① 在日尺度上,该地区地面实测紫外辐射UVA和UVB与卫星反演数据之间的相关系数达0.9以上,其中在全天空情况下UVA平均偏差为1.15 W·m -2、UVB 平均偏差为0.03 W·m -2,晴天条件下UVA和UVB的平均偏差分别为0.93 W·m -2和0.03 W·m -2;② 在季节尺度上,实测和卫星反演UVA和UVB的偏差夏季最大,分别为2.04 W·m -2和0.05 W·m -2,春冬两季次之,秋季最小;③ 红柳河地区在春夏两季受到气溶胶光学厚度(AOD)影响较大,呈现显著负相关;④ 云量越大,紫外辐射削弱程度越大,在多云条件下地面实测与卫星反演UVA与UVB偏差最大,分别为1.73 W·m -2和0.05 W·m -2。  相似文献   

5.
塔克拉玛干沙漠近地层湍流热通量计算方法比较研究   总被引:7,自引:4,他引:3  
利用2007年8月3日至10月31日在塔克拉玛干沙漠大气环境观测试验站取得的大气边界层观测资料,比较了涡动相关法、波文比法和空气动力学法计算得到的湍流热通量,分析了塔克拉玛干沙漠腹地能量平衡各分量的日变化特征。结果表明:波文比法、空气动力学和涡动相关法计算得到的塔克拉玛干沙漠腹地湍流热通量日变化特征是一致的,整个观测期间,空气动力学方法和波文比法计算得出的湍流通量大于涡动相关法。它们的顺序分别为,波文比法计算得出的湍流热通量最大,空气动力学方法次之,涡动相关法最小;塔克拉玛干沙漠腹地能量平衡各分量基本上以12:00时为中心,呈对称分布。净辐射、土壤热通量、感热通量具有非常明显的日变化特征。净辐射日最高值324 W·m-2出现在当地时间11:30,最小值-85 W·m-2出现在当地时间18:30;土壤热通量在12:00左右达到日最高值143 W·m-2,而20:00时出现最小值-69 W·m-2;感热通量在13:30时左右达到最高值178 W·m-2,19:00时左右出现最小值-7 W·m-2;相对于上述3个能量平衡分量,潜热通量的日变化特征不太明显。每日12:30左右出现潜热通量的最大值43 W·m-2,06:00时出现日最低值-1 W·m-2。  相似文献   

6.
《New Zealand geographer》1960,16(1):103-114
Book reviewed in this article:
GEOLOGY OF NEW ZEALAND. By Ferdinand von Hochstetter, translated by C. A. Fleming.
GUTHRIE-SMITH OF TUTIRA. By A. E. Woodhouse.
WEST COAST REGION. National Resources Survey, Part 1. Compiled by the Town and Country
TUWHARETOA: THE HISTORY OF THE MAORI PEOPLE OF THE TAUPO DISTRICT. By John Te H. Grace.
THE GREAT HARBOUR OF TARA: TRADITIONAL MAORI PLACE-NAMES AND SITES OF WELLINGTON HARBOUR AND ENVIRONS. By G. Leslie Adkin.
NORTHERN APPROACHES. By C. W. S. Moore.
EARLY DAYS IN CENTRAL OTAGO. By Robert Gilkison.
HANDBOOK TO THE ARTHUR'S PASS NATIONAL PARK. Christchurch: Arthur's Pass National Park Board, 1958
MOUNT COOK NATIONAL PARK HANDBOOK. Edited by W. P. Packard.
WORLD GEOGRAPHY. Edited by Otis W. Freeman and John W. Morris.
THE CONURBATIONS OF GREAT BRITAIN. By T. W. Freeman.  相似文献   

7.
REVIEWS     
Book reviewed in this article: THE QUEST FOR SECURITY IN NEW ZEALAND, 1840 to 1966. By W. B. Sutch COLONY OR NATION? By W. B. Sutch, Sydney  相似文献   

8.
陈锦年 《极地研究》1999,10(1):69-75
1IntroductionBeforethe1980s,Antarcticinvestigationsandtheirresearchdatawererelativelyfew.Sincethe1980s,alongwiththedevelopm...  相似文献   

9.
REVIEWS     
《New Zealand geographer》1959,15(2):203-212
Book reviewed in this article:
SIR JOSEPH BANKS IN NEW ZEALAND, FROM HIS JOURNAL. Edited by W. P. Morrell.
A HISTORY OF CANTERBURY, Volume I: To 1854. Edited by James Hight and C. R. Straubel.
A S urveyor on the W estland G oldeields
MY DEAR BANNIE: Gerhard Mueller's Letters from The West Coast 1865–6. Edited by M. V. Mueller.
M id -T wentieth C entury N ew Z ealand : Historian'S V iewpoint THIS NEW ZEALAND. By F. L. W. Wood.
M id -T wentieth C entury N ew Z ealand : GEOGRAPHERS VIEWPOINT
NEW ZEALAND: A REGIONAL VIEW. By K. B. Cumberland and J. W. Fox.
O ne H undred Y ears in H awkes B ay
THE STORY OF HAWKES BAY. By A. H. Reed.
M an and L and in the W estern P acific
L and and P eople in H ong K ong
LAND USE IN HONG KONG AND THE NEW TERRITORIES. By T. R. Tregear.
THE PATTERN OF ASIA. Edited by Norton Ginsburg.
AN ECONOMIC GEOGRAPHY OF EAST PAKISTAN. By Nafis Ahmad.  相似文献   

10.
我国荒漠植物的水分饱和亏   总被引:4,自引:1,他引:3  
本文研究了我国荒漠植物的水分饱和亏, 结果以典型的荒漠旱生植物珍珠和红砂最大, 分别为43.4%和35.6%, 梭梭34.7%, 籽蒿37.1%。中生植物刺槐和钻天杨水分饱和亏最小, 分别为15.0%和14.3%。这就表明, 荒漠植物在干旱条件下, 免于伤害的能力与水分饱和亏的大小密切相关。  相似文献   

11.
Book Reviews     
Book review in this Article
Atomic Spectra W. R. Hindmarsh
Magnetism and the Cosmos Edited by W. R. Hiodmarsh, F. J. Lowes, P. H. Roberts and S. K. Runcorn
The Craters of the Moon: an Observational Approach Patrick Moore and Peter Cattermole  相似文献   

12.
In this article, I describe how calculative practices of enumeration and visualization mobilized by policy actors to govern the multiple mobilities of e-waste and its re-materialization as value in the informal-recycling economies of Global South cities have resulted in e-waste being recalibrated as an “urban mine.” To properly govern and fully exploit e-waste qua urban mines, policy actors have developed the Best-of-2-Worlds (Bo2W) model. I show that the antecedent of the Bo2W model is the Clean e-Waste Channel implemented in Bangalore, India’s “Cyber City,” which has retroactively been recast as the first successful implementation of the Bo2W model. While policy actors mobilize Bangalore’s success to boost this model and facilitate its mobility to other Global South cities, I conclude by offering a critical assessment of the Bo2W model for the prospects of informal recyclers in Global South cities and the creation of uneven geographies of e-waste toxicity.  相似文献   

13.
Based on measured hydrological data by using ship-mounted Acoustic Doppler Current Profiler (ADCP) instrument, we analyzed shapes of river cross sections of the middle Yangtze River basin (mainly focusing on Makou and Tianjiazhen river reach). Hydrodynamic properties of river channels were also discussed. The research results indicate that nonlinear relationships can be identified between river-width/river-depth ratio (W/D ratio), sizes of cross section and mean flow velocity. Positive relations are detected between W/D ratio and mean flow velocity when W/D<1; and negative relations are observed when W/D>1. Adverse relationships can be obtained between W/D ratio and cross-section area. Geomorphologic and geologic survey indicates different components of river banks in the wider and narrower river reaches respectively. These may be the main driving factors causing unique hydrological properties of river channels in the middle Yangtze River basin. Narrower river cross sections tend to raise water level in the upstream river reach near narrower river channel, giving rise to backwater effects. River knots can cause serious backwater effects, which is harmful for flood mitigation. However river knots will also stabilize river channel and this will be beneficial for river channel management. The results of this paper may be helpful for flood mitigation and river channel management in the middle Yangtze River basin.  相似文献   

14.
Reviews     
Environmental Management and Change in Plymouth and the South West. By M ark B lacksell , J udith M athews and P eter S ims .
People, Environment, Disease and Death. By M elvyn H owe .
Timing global cities. Edited by S.G.E. G ravesteiin , S. van G riensven and M.C. de S midt
Modern Geographical Thought By R ichard P eet .
The Political Ecology of Bananas: Contract Farming, Peasants, and Agrarian Change in the Eastern Caribbean. By L awrence S. G rossman
The Holocene: an Environmental History. By N eil R oberts
Histoire de la Géographie Franáise de 1870 à nos jours. By P aul C laval
Battling the Elements, Weather and Terrain in the Conduct of War. By H rold A. W inters with G erald E. G alloway , W illiam I. R eynolds and D avid W. R hyne
The Military Use of Land, A History of the Defence Estate. By J ohn C hilds
Flood Studies in India. Edited by V ishwas S. K ale
The Northridge Earthquake: Vulnerability and Disaster. By R obert B olin with L ois S tanford
The Assessment of the Status of Human Induced Soil Degradation in South and Southeast Asia. By G.W.A. van L ynden and L.R. O ldeman
Asia Pacific: New Geographies of the Pacific Rim. Edited By F.R. W atters and T.G. M cgee  相似文献   

15.
Book Review     
Book review in this Article
Applied Geophysics W. M. Telford, L. P. Geldart and R. E. Sheriff
Advances in Solar System Magnetohydrodynamics Eds E. R. Priest and A. W. Hood
Continents in Motion: The New Earth Debate Walter Sullivan, Adam Hilger (IOP Publishing, Bristol, UK) & American Institute of Physics (New York)  相似文献   

16.

The Place of the Ideal Community in Urban Planning. Thomas A. Reinbr.

Water Atlas of the United States. Robert S. Collins, James J. Geraghty, David W. Miller.

The Rebirth of African Civilization. Chancellor Williams.

Alexander von Humboldt. L. Kellner.

Divided Germany and Berlin. Norman J. G. Pounds.

Larousse Encyclopedia of World Geography (Europe). Pierre Deffontaines, gen. ed. W. G. Moore

Yugoslaviu and the New Communism. George W. Hoffman and Fred W. Neal.

Theoretical Geograghy. William Bunge.

Political Geography. Norman J. G. Pounds.

Observaciolzes sobre la Reforma en Italia. Angel Palerm.

Borgo a Mozzano: Technical Assistance in a Rural Community in Italy. L. E. Virone.

Economic Geography. John W. Alexander.  相似文献   

17.
Book Reviews     
Books Reviewed in this Article:
Physical Geology G. Gorshkov and A. Yakushova (Translated by A. Gurevich) (Mir Publishers, Moscow, 1967. 586 pp., 30s., Central Books)
Solar-Terrestrial Physics Edited by J. W. King and W. S. Newman (Academic Press, New York, 390 pp. 90s, $16.50)
Methods in Palaeomagnetism  相似文献   

18.
南大洋二氧化碳源汇分布及其海-气通量研究   总被引:1,自引:1,他引:1       下载免费PDF全文
在 1 999年 1 2月 - 2 0 0 0年 2月“雪龙”号科学考察船往返于中山站和长城站期间 ,进行了大气及海表层 CO2 分压的连续测量。研究结果表明 ,在 80°W- 0°- 80°E之间 ,南大洋基本上是大气 CO2 的汇 ,尤其在 45°W- 3 0°W及 1 0°W- 1 0°E之间 ,是 CO2 的强汇区 ,往返的两次观测结果十分相似。观测发现 ,南大洋 1月份吸收大气 CO2 的能力近两倍于 1 2月份 ,这是由于该海域1月的生产力比 1 2月份高 ,因而反映了初级生产对大气 CO2 吸收的显著影响。利用最新的 K值计算方法表明 ,1月份二氧化碳的入海通量为 3 .98mol/(m2 · a) ,1 2月份的为2 .1 3 mol/(m2 · a) ,综合两个月的值平均 ,南大洋夏季 CO2 的平均通量为 3 .0 6 mol/(m2 · a) ,是南半球夏季一个重要的汇区  相似文献   

19.
土地沙漠化过程的数学模型   总被引:6,自引:1,他引:5  
本文从分析沙漠化成因机制的角度出发, 提出了沙漠化过程的数学模型: Y=At·f(P, W), 并由此建立了沙漠化因素定量分析的方程:dY/dt/Y=dA/dt/A+α dp/dt/p+β dW/dt/W。从而使人类活动对沙漠化作用的定量化成为可能。  相似文献   

20.
渭南黄土台塬晚新生代环境与城市建设   总被引:2,自引:0,他引:2  
徐馨  邢肇祺 《地理研究》1989,8(2):16-27
根据对W7、W8两钻孔中的孢粉、微体古生物化石和矿物成分分析,结合野外考察及古地磁地层年代资料与标准剖面对比,作者提出本区第四纪地层划分的初步意见并阐述了晚新生代环境.根据W7、W8两孔相当层位的深度变化,推断张性正断层的存在,进而讨论了与城市建设有关的地下水资源和黄土塌陷问题.  相似文献   

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