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1.
彭州市立体农业气候资源的研究(二)热量资源分析   总被引:2,自引:0,他引:2  
利用彭州市境内市气象站,新兴,白果坪的日平均气温资料,进行热量资源分析。结果表明,彭州市7-8月为最热月,多年平均温度低于24.9℃,12-2月为最冷月,多年平均温度高于1.7℃。大多数年全年稳定通过0℃,可一年四季进行农业耕作,有利于作物越冬和多年生作物的种植,生长期长,积温丰富。界限温度的初,终日期及持续日数变化较大,积温际变化显著,热量资源随海拔高度增加而减少,各界限温度的初日推迟,终日提前,持续日数和积温减少,温度强度也降低,形成显著的立体农业气候。  相似文献   

2.
白银市"四旱"气候特征及成因研究   总被引:2,自引:0,他引:2  
利用白银市4站1957—2000年44年的降水资料,计算了“四旱”干旱指数,分析了各旱段干旱的气候特征。结果表明:全市每年都有干旱发生,即每年至少有一站发生某一干旱。在4个旱段中,春旱频率最高,春末夏初旱次之,干旱频率从甫至北增加;全市90%的年份降水偏差一致,但南部的降水比北部多一倍且稳定性较好。另外初步分析了“四旱”的形成原因。  相似文献   

3.
针对当前从气象风险角度开展小麦条锈病与气象关系研究甚少的状况,从农业气象灾害风险分析理论出发,采用相关分析、层次分析和极差正规化等方法,建立了包含气候条件和寄主存在数量两个环境因子的四川省小麦条锈病春季流行农业气候风险模型,并划分了高、中、低风险等级的指标.在此基础上,利用GIS技术对四川省小麦条锈病春季流行的农业气候风险进行了区划.结果表明,四川省的川西高原地区、川西南山地和盆地西南部是小麦条锈病春季流行低风险区,盆地大部地区是中、高风险的集中区.区划结果为进一步做好四川省小麦条锈病的分区预报和综合防治方面提供科学依据.  相似文献   

4.
柴达木盆地矿产开发中环境地质问题及防治对策   总被引:2,自引:2,他引:0  
在柴达木盆地环境现状实际调查基础上,根据调查资料论述了柴达木盆地地区矿产开发引起的主要环境地质问题及其危害。分析了引起土地沙化.土壤盐渍化,水土污染,崩塌地面塌陷,生态环境恶化产生原因,并在地质环境保护方面提出合理化建议,以期为西部开发过程环境保护提供依据。  相似文献   

5.
稀土是世界各国的战略性关键金属矿产资源,而中重稀土尤为重要。老挝境内分布着大量不同时代花岗岩类,且气候湿热多雨,风化作用强烈,为离子吸附型稀土矿的形成创造了有利条件。为查明老挝稀土资源成矿地质特征和资源分布特征,分析其投资开发前景,对整个老挝境内开展了大量系统的野外调研及相关分析测试工作,并且汇总了老挝稀土资源勘查工作进展。研究结果表明,老挝稀土资源成矿特征可类比中国南方地区,属于典型的风化壳淋积型矿床,矿体主要富集于花岗岩类风化壳全风化层,盖层厚度相对中国较大。矿体呈层状、似层状和透镜体状,厚度数米到二十多米。离子相稀土平均品位为0.4‰~0.7‰,大部分稀土配分模式同江西赣州信丰稀土矿相似,属富集中重稀土元素的中钇富铕型。老挝稀土资源主要分布于北部的川圹省和华潘省,预计两省稀土资源总量可达到60万t。随着老挝稀土政策的开放和中国稀土战略的逐步完善,投资开发老挝稀土资源,建立稀土资源的海外战略基地,可以长期稳定地支撑中国对离子吸附型稀土资源的需求,同时也可以为加强两国合作、共建中老命运共同体做出突出贡献。   相似文献   

6.
近日,淄博市沂源县矿整办提出要抓好三项工作,明确三项责任,强化三个管理,注重三个结合,进一步整顿和规范山石资源开发秩序。  相似文献   

7.
广西旅游地学资源丰富,在区位、成景条件,景观种类数量、质量、旅游业的形势、开发程度、客源市场、旅游产品、研究水平等特色明显;如何变资源为效益,必须从发展方向与总体目标,重点区建设模式、开放力度、设施配套及环境保护等方面认真研究,合理开发。  相似文献   

8.
城步苗族自治县旅游资源丰富,县政府和旅游局紧随潮流趋势,制定了一套招商引资发展旅游业的优惠政策,为城步县旅游资源开发提供了一个广阔的发展空间。随着各种旅游资源的开发,形成了各类特色鲜明的景观,但是在开发过程中遇到了一些问题。本文就针对这些问题的表现、原因及解决途径展开论述。  相似文献   

9.
柴达木盆地盐湖钾硼锂资源概况及开发前景   总被引:1,自引:0,他引:1  
柴达木盆地分布有大量第四系盐湖,其中赋存大量钾、硼、锂、钠、镁资源,具有巨大的开发利用价值,已经成为资源开发的热点地区.通过对柴达木盆地盐湖钾、硼、锂资源概况、开发条件和开发前景作了介绍和分析,认为柴达木盆地盐湖资源大规模开发以后,可以解决我国硫酸钾供应问题,缓解国内氯化钾供应紧张的局面;综合产出的硼酸盐和锂盐产品能够参与国际市场竞争.  相似文献   

10.
1钾盐开发的重要性钾盐中的钾作为植物所需的氮、磷、钾三大元素之一,在植物体内起着非常重要的作用,土壤中如缺钾会造成农作物早衰、抗病、抗旱能力降低,农产品品质变差、产量下降等问题。因此,开发钾肥资源,增加钾肥品种及供应量,已成为我国农业再上新台阶亟需解决的问题。为  相似文献   

11.
彭州市立体农业气候资源的研究(一)降水资源分析   总被引:4,自引:0,他引:4  
分析了彭州市境内位于不同海拔高度的4个观测站的降水资料,结果表明,彭州市雨量充沛,但降水量的年际变化显著,雨季起、止时间和雨季长、短的年际变化很大,降水的时间分配极不均匀,因为这4个站具有相同的气候背景、,降水量的年、季、月变化呈现基本一致的规律和趋势,但因为海拔高度不同等气候背的差异,4站的降水特点又显著不同。降水量随海拔高度的升高而增加,降水变幅和雨日也阴海拔高度的升高而增加,大降水过程具有明显的局地性,不同海拔高度的旱、涝情况亦有差异,降水的空间分布表现出明显的立体性特征。  相似文献   

12.
The unconventional oil and gas resources presented in oil shales have meant these potential sources of hydrocarbons,which has become a research focus. China contains abundant oil shale resources,ranking fourth in the world,with ca. 7 254. 48 × 10~8 t within 24 provinces,including 48 basins and 81 oil shale deposits. About 48% of the total oil shale resources are concentrated in the eastern resource region,with a further 22% in the central resource region. 65% of the total quantity of oil shale resources is present at depths of 0-500 m,with 17% of the total resources being defined as high-quality oil shales yielding more than 10% oil by weight.Chinese oil shale resources are generally hosted by Mesozoic sediments that account for 78% of the total resources. In terms of the geographical distribution of these resources,some 45% are located in plain regions,and different oil shale basins have various characteristics. The oil shale resources in China represent a highly prospective future source of hydrocarbons. These resources having potential use not only in power generation and oil refining but also in agriculture,metal and chemical productions,and environmental protection.  相似文献   

13.
对白银市4个代表站1957~1996年6~8月的降水量场进行经验正交函数(EOF)分解,得到方差贡献最大的第一特征向量,对第一特征向量的主分量建立均生函数模型并外推5年预报,用预报出的时间系数乘以相应的特征向量得到6~8月降水量场的预报值。  相似文献   

14.
In the global climatic change, China’s climatic change will be more complicated and its impact on the agroclimatic resources and agricultural production will also be more obvious. Therefore, it is absolutely necessary to take the agroclimatic resources as a comprehensive climatic information system for evaluating the impact of climatic change on agriculture and exploring the correspondent ways to deal with it. This article studies the impact of climatic change on China’s thermal resources and make a correlation analysis of the climatic condition and the agroclimatic thermal resources in order to establish a regression equation and made simulant computation with Monte Cario Method. In addition, it analyses the change of the thermal resources possibly resulted from climatic change, evaluates its impact on agricultural, and finally sets up the correspondent countermeasures.  相似文献   

15.
Siderophores from Marine Microorganisms and Their Applications   总被引:4,自引:1,他引:3  
1 Introduction Ironisanessentialelementwhichisdifficulttoob tainduetoitslowsolubilityunderthephysiologicalconditions ,anditisalsothemostimportanttransitionmetalionfornearlyalllivingsystems.Manypatho genicbacteriausuallyobtainironfromtheiron bind ingprot…  相似文献   

16.
This paper discusses the constraining factors to sustainable utilization of water resources in China,and the countermeasures to realize sustainable water utilization.The result of comprehensive analysis shows that constraining factors to sustainable utilization of water resources in China are complicated, including physical geographi cal factors and socio-economic factors, such as uneven distribution of water resources at temporal and spatial scales,inappropriate institutional arrangement and non-water-saving and non-water-conservation production and life mode.The countermeasures against constraining factors to water resources sustainable development are put forward as follows: l) using wetlands and forests, and through spatial conversion to realize temporally sustainable supply of water resources; 2) transferring water between basins and areas and developing various water resources in water shortagearea; 3) establishing water-saving society; 4) strengthening water pollution control and water resources protection;and 5) establishing unified water resources management mechanism.  相似文献   

17.
It is efficient and reliable to investigate the reed resources of Bosten Lake in Xinjiang, characterized by complicated types of reed land and very different reed growth using colour infrared aerial photos, Landsat images and multi band imagery. At first, on the basis of Landsat images and relevant data, we analyzed the ecological environment of the studied area, the characteristics of reed land types and imaging mechanism to determine the program for abstracting remote sensing information and aerial photographic conditions:On the processed Landsat images and aerial photos, we considered typically geographic features and reed land types, preselected ground sampling sections and sites, then determined indexes classifying reed land types according to sampling data and image characteristics, established various interpretation keys, drew distribution maps of reed land types and measured the area of various types of reed land following geometric correction. On the other hand, based on sampling values and hab  相似文献   

18.
Study on coordiantion among population(P), resources(R), environment(E), and development(D) (PRED) has comprehensive and extensive contents, which serves as the core of sustainable development. Since the 1980s, PRED has been becoming one of the most important regional studies in China. Based on existing research and collected data, this study analyses the course of the PRED evolution in Shanghai during 1978–1995. Seven indicators were selected to assess the evolution characteristics and interaction mechanism of Shanghai PRED, including growth rate of GDP, growth rate of population, growth rate of industry energy consumption etc. These indicators were designed to reflect representativeness, relativity and data availability. This study showed that there was obvious asynchronous among indicators and annual change of single indicator lacked of regularity, coordination between environment and economic remains the main challenge facing Shanghai, and the key readjusted factors will be population growth rate, GDP growth rate and per residential area growth rate. The study further pointed out that plan, structure and system power were equally important for the more coordinate development in Shanghai. Detailed dicussion on the systematic measurement in each aspect of P, R, E, D indicated that higher development level is the essential basis for Shanghai PRED coordination. Foundation item: Qimingxin Scheme Sponsored by Shanghai Science and Technology Committee. Biography: YUAN Wen(1965–), female, a native of Changzhou City, Jiangsu Prorince, Ph. D in environmental evolution and sustainable development, associate professor of East China Normal University.  相似文献   

19.
This paper aims to establish an index system for evaluation of agricultural resources use efficiency (ARUE) in grain production and discuss the causes of low efficiency and high consumption of agricultural resources in Changshu of Jiangsu Province, Taihe of Jiangxi Province and Ausai of Shaanxi Province in China by analyzing the data about meteorology, soil, water consumption and grain production. Agro-ecological Zone (AEZ) method was adopted to calculate the potential productivity, and synthetically multivariate equation was used to evaluate the ARUE of study areas. This paper can be concluded as: 1) the agricultural resources in grain production can be classified into five categories, i.e., climatic resources, water resources, land resources, biological resources and assistant resources, and 15 indexes were selected to evaluate their use efficiency in grain production; 2) the values of ARUE in grain production are 0.5868, 0.6368 and 0.5390 respectively in Changshu, Taihe and Ansai; and 3) Changshu ranks the highest among the three study areas in terms of the use efficiency of climatic resources and biological resources (evaluation values are 0.0277 and 0.1530), but Taihe tops the three in terms of the use efficiency of water resources, land resources and assistant resources (evaluation values are 0.0502, 0.2945 and 0.1379 respectively). However, the ARUE remains always low in Ansai for all the resources. The inefficiencies are caused by poor grain revenue in Changshu, deficient agriculture investments in Taihe and unfavorable natural conditions in Ansai.  相似文献   

20.
四川省农业资源开发利用现状及可持续利用对策   总被引:1,自引:0,他引:1  
采用系统、综合分析法,全面、系统、科学的分析评价了四川农业资源开发利用现状及其发展变化趋势,针对四川耕地面积不断减少、人地矛盾日趋尖锐、水土流失严重、水资源利用率低、水资源污染日趋严重等制约四川经济社会可持续发展的主要因素,提出了切实保护耕地、加强生态环境保护和建设、防治水资源污染、提高水资源利用率和供水能力等一系列实现农业资源可持续利用的对策和措施.  相似文献   

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