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11.
2003年异常气候对清徐葡萄的影响   总被引:1,自引:0,他引:1       下载免费PDF全文
气候对葡萄生长发育的影响十分关键,以光照、温度和降水三要素为主。利用清徐地面气象资料,根据葡萄各生育阶段对气候资源的需求特点,比照该时期年内的实际气候状况,着重分析年度内气候异常与葡萄产量下降、品质降低之间的关系,并就如何减缓气候对葡萄生产的不利影响进行初步探讨。  相似文献   
12.
中国葡萄气候区划探讨   总被引:6,自引:0,他引:6  
根据葡萄的生物学特性及其对气候条件的要求,在全国范围内选取83个站点,按照9个农业气候指标,利用模糊聚类的数学方法,将全国划分为6个不同的葡萄气候区,并就各区的气候特点和品种选择作出分区评述。  相似文献   
13.
以中国环渤海地区葡萄主产区为研究对象,利用1980-2019年研究区域内303个气象站逐日气象资料、葡萄发育期资料和葡萄涝渍灾情资料,基于相对湿润度方法构建葡萄逐日涝渍指数M5i,以历史灾情反演和灾变过程解析为主线,采用正态分布的Lilliefors检验和t分布区间估计等方法,构建适用于中国环渤海地区葡萄主产区的葡萄涝...  相似文献   
14.
肖生春  李晓云  刘发民 《中国沙漠》2000,20(Z2):146-149
对延津沙地引种筛选的葡萄品种及其重要栽培技术加以总结,以期对周边同类型沙地提供可行的配套技术,推动沙地农业产业结构的调整。  相似文献   
15.
The Bamsk gold-ore deposit is located in the Amur region, the Far East of Russia. It is confined to the Early Cretaceous volcanic-plutonic uplift of central type, located in the Stanov folded-clumpy Pre-Cambrian system. The deposit is presented by a series of gold-bearing quartz and carbonate-quartz vein-stringer zones. They are confined to the super-intrusive zone of the Nevachansk subvolcanic intrusion of sienite-porphyric composition. The mineralization is being controlled by zone of fractures developed in the autochthone ofthe Bamsk fault. Quartz, carbonates and sericite prevail in the composition of ores. The quantity of ore minerals doesn't exceed 1%~5%. Pyrite, chalcopyrite, galena and native gold are widely spread. Sheelite, gold and silver tellurides, sulphobismuthites, acanthite, sphalerite and cinnabar are less developed. Four stages of mineralization have been distinguished. Gold-sulphide-sulphosalt ore with tellurides of gold and silver is productive for gold. The following set of elements is typomorphic for the ores of the deposit: Au, Ag, Cu, Bi,Mo, Pb and Sb (W1, Pb1, Mo) -Cu- (Ag, Bi, Sb, Mn, W1, Pb2) form the vertical series of zoning. Rocks, enclosing the mineralization are exposed to the processes of listvenitization-beresitization. The processes of gumbeization and argillization are less manifested. The age of the gold mineralization, determined by Rb-Sr method on ore-accompanying minerals, is 130.6 Ma.  相似文献   
16.
Sedimentary facies of the Tsagayan Formation is distributed in the eastern Zeya-Bureya Basin has been analyzed. The formation is of the Maastrichtian to Danian in age and characterized by the cyclicity of the fining-upwards successions. Analysis of environmental changes during the K/T boundary is the focus of this study. Five facies have been identified: Facies A, thick and laterally extensive coarse-grained to medium-grained sandstone units, interpreted as channelfill deposits; Facies B, parallel-laminated to massive mudstone units interpreted as interchannel lakes and flood plain deposits; Facies C, sheet-like medium-grained to fine-grained sandstones interpreted as crevasse splay deposits;Facies D, coal to coaly mudstone beds interpreted as deposits ofpeatlands; Facies E, very poorly sorted sandy mudstone beds interpreted as debris flow deposits. Fluvial environments with the low-relief flat topography was inferred. A channel transported large volumes of clasts, and a flood basin with interchannel lakes and peatlands was deciphered. Any distinct change of sedimentary environments has not been identified throughout the Tsagayan Formation (including the K/T boundary). However, two beds of debris flow deposits were identified. The one occurs at the uppermost part of the lower Tsagayan Subformation and contains dinosaur fossils. The other is intercalated in the upper Tsagayan Subformation.  相似文献   
17.
GIS and RS techniques have been applied to interpret satellite data in 1992, 2000 and 2010. Further, the ecological environment factors of these three periods and the data for various types of land use have been obtained. LUDI in the Amur River Basin from 1992 to 2010 has been quantitatively analyzed by using the land use dynamic (LUDI) model and of land use transfer matrix model. The results indicated that from 1992 to 2010 the LUDI of land desertification is greatest, and is the most dramatic change. The comprehensive land use dynamic in the study area is 15.25, hence the land type is characterized by rapid change. In addition the area of woodland and farmland continues to increase, which has been mainly transformed from the mixture of forestland and grassland, marsh and wetland, this is an outcome of the production of shelter-forest plantation in North China, Northeast China and Northwest China. In the ten years period of the study, the area of desertified land has increased, changing mainly from a mixture of woodland and grassland. This study can rovide data for eco-geological environment management.  相似文献   
18.
The intensity of placer formation is controlled by many factors, mainly by the erosion level of orebearing structures. Their deep erosion and long-term denudation resulted in the formation of numerous, often large placers with fine gold, which lost their relation with bedrocks and were derived mainly by rewashing of loose deposits from the depressions adjacent to the ore-bearing orogens. These placers are developed in many gold-bearing areas: Dambuki, Sutara, Erik, and others. Rich placers with coarse gold of high fineness were formed via erosion of gold mineralization that was previously metamorphosed by post-ore granitoids (Niman and Kerbi regions, Central Sikhote Alin).  相似文献   
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20.
This paper considers results of geodynamic studies using the GPS method in the territory of the Far East. GPS measurements using TRIMBLE-4700 geophones were launched along the Sikhote Alin profile in 2003. The technology of the GPS measurements and the problems of selecting the measurement sites and network configuration with reference to the region’s structure are discussed. The results of GPS measurements in 2003–2006 were used to study the fault system of the Far East continental margin. Different models of the Eurasia rotation (from the known NNR-NUVEL-1A to the recent ones) were analyzed. The solid-body rotation of Eurasia was predicted in the framework of the AR-IR-2006 model with a pole located at 51.045°N latitude, 255.842° longitude and rotating at a rate of 0.2423°/Ma. The parameters of the Amur plate rotation were preliminarily estimated (57.6° ± 0.5°N, 117.1 ± 0.5°E, and 0.083° ± 0.004°/m.y) using results on the Sikhote Alin and Transbaikalian network.  相似文献   
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