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Received date: -- Foundation item: The national key research project: Field water balance its regulation techniques water potential productivity its proper exploitation in typical dryland farming areas of northern China for the Ninth Five 《地理学报(英文版)》2000,(3)
1 IntroductionIn natural conditions, field water surplus or deficit is different between field water requirement and field water supply by nature. Field water requirement can be expressed either as potential field evapotranspiration or as crop water requirement. Potential field evapotranspiration is also called reference crop evapotranspiration which is defined as "the rate of evapotranspiration from an extensive surface of 8 to 15 cm tall, green grass cover of uniform height, actively growing… 相似文献
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中国区际间主要农产品虚拟水流动格局稳定性 总被引:6,自引:0,他引:6
为分析中国区际间虚拟水流动格局的稳定性及为将来研究虚拟水流动格局维持机制提供理论依据,通过构建1999-2010年中国区际间主要农产品虚拟水流量关系矩阵,引入生态网络安全系统相关概念,构建虚拟水流动格局网络稳定性模型,结果表明:东北、黄淮海和长江中下游地区是中国虚拟水的主要调出区;其他区域是调入区;虚拟水流动格局网络系统的信道数目减少,信道容量逐年降低;系统聚合度和系统冗余度亦呈波动降低趋势;系统网络使用率呈现降低趋势;系统网络空闲率呈增加趋势;网络系统指标表明中国区际间主要农产品虚拟水流动形成的网络系统稳定性逐年降低。最后,提出建立粮食安全预警系统等5方面应对措施。 相似文献
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农作物生产结构与布局是农业地理学探讨的传统研究主题,开展农作物生产格局演变特征与机制研究,可为区域农业生产要素的优化配置提供参考依据。论文运用区位基尼系数、重心移动模型、比较优势指数等方法,揭示1995—2019年广西粮食、糖料、水果和蔬菜4类主要农作物生产格局的演变特征,剖析其形成机制,据此提出相关优化建议。结果表明:粮食作物“退”、糖果菜“进”构成主要农作物竞争的基本态势;粮食、蔬菜生产空间分布相对分散,糖料生产地理集聚趋势明显,水果生产由相对集中走向分散;主要农作物综合比较优势受规模比较优势主导,粮食生产劣势明显,糖料生产具有绝对规模比较优势和综合比较优势,水果、蔬菜生产规模比较优势突出但效率比较优势有待提升。资源禀赋的约束、市场供需和比较效益的主导、乡村社会发展要素变化的诱发、制度环境的引导/修正、集聚经济的循环累积等多种力量综合作用推动农作物生产格局的演变。特殊的区情决定了广西农作物生产应统筹经济功能、社会功能和生态功能,通过结构调整、产业集聚、空间优化,推进农作物生产从规模扩张向综合效益提升转型。 相似文献
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中国北方地区用水进入低增长和微增长阶段的必要性和可能性 总被引:1,自引:0,他引:1
水资源如何能够得到长期和可持续的供应和利用,已成为全社会十分关注的重大问题。中国用水问题突出的是在北方地区。而北方地区依赖“开源”解决水问题已面临极限挑战。本文论证了中国北方地区未来进入用水微增长乃至零增长阶段的可能性和必要性。其主要依据是近年来的用水增长态势是进入稳定低增长阶段的前兆;农业用水量增长态势呈波动状态,效率有所提高;工业年耗水量在波动中有所下降;生活用水特别是城镇生活用水上升,但占全部用水的比重小。在政府管理和用水理念方面,需要在用水需求、用水观念、节水措施、制度建设上作出与时俱进的调整。 相似文献
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WANG Xiqin ZHANG Yuan LIU Changming 《地理学报(英文版)》2007,17(3):304-316
In this article the meaning of the quantity and quality of environmental flows of river in dualistic water cycle is discussed, and compared with the meaning of unitary water cycle. Based on the analysis of the relationship between environmental flows of river requirements, the efficiency of water resource usage, the consumption coefficient, and the concentration of waste water elimination, the water quantity and water quality calculation method of the environmental flows of river requirements in dualistic water cycle is developed, and the criteria for environmental flows of river requirements are established, and therefore the water quantity-quality combined evaluation of natural river flows requirements are realized Taking the Liaohe River as a model, the environmental flows of river requirements for Xiliao River, Dongliao River, mainstream Liaohe River, Huntai River and northeast rivers along the coasts of the Yellow and Bohai seas in unitary water cycle are calculated, each taking up 39.3%, 63.0%, 43.9%, 43.3% and 43.5% of runoff respectively. Evaluated according to Tennant recommended flow, the results show that: except Xiliao River is "median", the rest are all upon "good", the Dongliao River is even "very good". The corresponding results in dualistic water cycle are that, the proportion of natural flows for each river is 57.5%, 74.1%, 60.8%, 60.3% and 60.4%; while the combined evaluation results show that: considering "quantity", except Xiliao River, the rest rivers can all achieve the "quantity" criteria of the en- vironmental flows of river requirements, but if considering the aspect of "quality", only Dongliao River can reach the "quality" standard. By water quantity-quality combined evaluation method, only Dongliao River can achieve the criteria. So the water quality is the main factor that determines whether the environmental flows can meet the river ecosystem demands. 相似文献
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东北地区参考作物蒸散确定方法研究 总被引:30,自引:4,他引:30
运用FAO-Penman-monteith方法和Hargreaves方法对中国东北地区4个气候大区16个气象台站的参考作物蒸散(ET0)进行了研究,并对FAO-Penman-monteith方法和Hargreaves方法的计算结果进行分析。发现:Hargreaves方法可适用于东北地区,尤其是亚湿润地区,但是相对于FAO-Penman-monteith方法,该方法还存在偏差,特别是半干旱地区。为了进一步提高Hargreaves方法的精度,对其进行了修正,得出比Hargreaves方法精度更高的适于东北地区参考作物蒸散计算的方程,为精确、实用地确定作物需水量和合理的灌溉制度提供了科学依据,有利于水资源的合理利用,尤其是水资源缺乏的半干旱地区。 相似文献
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西北地区生长季参考作物蒸散变化成因的定量分析 总被引:14,自引:0,他引:14
基于FAO Penman-Monteith 公式计算了我国西北地区126 个测站1961-2009 年的生长季(4-10 月) 参考作物蒸散(ET0) 对平均气温、风速、相对湿度和太阳辐射的敏感系数,并结合各气象因子的多年变化特征定量讨论参考作物蒸散变化的原因。结果表明:风速和气温的敏感性虽然相对较低,但因其显著变化,成为引起ET0变化的主导因子,贡献达到-5.22%和3.29%;太阳辐射和相对湿度敏感性较大,但因变化小,贡献仅为-0.76%和0.63%。空间上,气温在西北地区对ET0 变化多为正贡献,风速和太阳辐射多为负贡献;相对湿度在西部多为负贡献,东部为正贡献。估算的4 个气象因子共同作用引起的ET0变化在趋势、数值和空间分布上均与ET0的实际变化基本一致,两者的相关系数高达0.99,表明结合敏感性分析和气象因子的多年变化来解释西北地区ET0变化的原因兼具合理性和可行性。而且该方法弥补了趋势分析法、相关分析法和敏感性分析法的不足,为定量分析ET0变化成因提供一条新思路 相似文献
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西北地区气候暖干化对作物气候生态适应性的影响 总被引:11,自引:1,他引:11
在综述西北地区现代气候变化基本特征是暖干化的基础上,重点揭示了冬小麦、春小麦 (夏粮)、玉米、马铃薯、谷子、糜子(秋粮)和棉花、胡麻、冬油菜、酿酒葡萄(经济作物)等10种主要作物的热量指标、水分指标和生长发育状况等对现代气候暖干化的响应特征。气候变暖对作物热量生态适应性的影响非常显著,作物需要热量指标比变暖前有提高的趋势;气候变干对作物水分生态适应性的影响非常敏感,作物需要水分指标比变干前有增多的趋势。气候暖干化对作物气候生态适应性的影响总体来说是利弊并重。对灌溉区作物是利多弊少,建议要创建干旱区现代农业发展模式来应对;对旱作区作物是弊远大于利,建议要建立一整套旱作农业生产机制来适应气候暖干化。提出了作物气候生态适宜度是气候暖干化对作物产生重大影响的重要原因。 相似文献
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基于二元水循环的河流生态需水水量与水质综合评价方法——以辽河流域为例 总被引:1,自引:0,他引:1
In this article the meaning of the quantity and quality of environmental flows of river in dualistic water cycle is discussed,and compared with the meaning of unitary water cycle. Based on the analysis of the relationship between environmental flows of river re-quirements,the efficiency of water resource usage,the consumption coefficient,and the concentration of waste water elimination,the water quantity and water quality calculation method of the environmental flows of river requirements in dualistic water cycle is developed,and the criteria for environmental flows of river requirements are established,and therefore the water quantity-quality combined evaluation of natural river flows requirements are realized. Taking the Liaohe River as a model,the environmental flows of river requirements for Xiliao River,Dongliao River,mainstream Liaohe River,Huntai River and northeast rivers along the coasts of the Yellow and Bohai seas in unitary water cycle are calculated,each taking up 39.3%,63.0%,43.9%,43.3% and 43.5% of runoff respectively. Evaluated according to Tennant recommended flow,the results show that: except Xiliao River is "median",the rest are all upon "good",the Dongliao River is even "very good". The corresponding results in dualistic water cycle are that,the proportion of natural flows for each river is 57.5%,74.1%,60.8%,60.3% and 60.4%; while the combined evaluation results show that: considering "quantity",except Xiliao River,the rest rivers can all achieve the "quantity" criteria of the en-vironmental flows of river requirements,but if considering the aspect of "quality",only Dongliao River can reach the "quality" standard. By water quantity-quality combined evalua-tion method,only Dongliao River can achieve the criteria. So the water quality is the main factor that determines whether the environmental flows can meet the river ecosystem de-mands. 相似文献
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In this article the meaning of the quantity and quality of environmental flows of river in dualistic water cycle is discussed, and compared with the meaning of unitary water cycle. Based on the analysis of the relationship between environmental flows of river re-quirements, the efficiency of water resource usage, the consumption coefficient, and the concentration of waste water elimination, the water quantity and water quality calculation method of the environmental flows of river requirements in dualistic water cycle is developed, and the criteria for environmental flows of river requirements are established, and therefore the water quantity-quality combined evaluation of natural river flows requirements are realized. Taking the Liaohe River as a model, the environmental flows of river requirements for Xiliao River, Dongliao River, mainstream Liaohe River, Huntai River and northeast rivers along the coasts of the Yellow and Bohai seas in unitary water cycle are calculated, each taking up 39.3%, 63.0%, 43.9%, 43.3% and 43.5% of runoff respectively. Evaluated according to Tennant recommended flow, the results show that: except Xiliao River is “median”, the rest are all upon “good”, the Dongliao River is even “very good”. The corresponding results in dualistic water cycle are that, the proportion of natural flows for each river is 57.5%, 74.1%, 60.8%, 60.3% and 60.4%; while the combined evaluation results show that: considering “quantity”, except Xiliao River, the rest rivers can all achieve the “quantity” criteria of the en-vironmental flows of river requirements, but if considering the aspect of “quality”, only Dongliao River can reach the “quality” standard. By water quantity-quality combined evalua-tion method, only Dongliao River can achieve the criteria. So the water quality is the main factor that determines whether the environmental flows can meet the river ecosystem de-mands. 相似文献
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水—经济空间关系是干旱区与半干旱区水资源研究的热点,揭示水—经济空间分布演变规律和因果关系,可为优化水资源合理配置、合理部署产业结构调整政策提供理论和决策参考。研究应用水足迹理论,核算新疆各地州1991—2015年农作物水足迹,结合信息熵值理论分析新疆各地州农作物水足迹、国内生产总值、第一产业增加值其熵值的空间演变规律及因果关系。结果表明:新疆农作物水足迹与第一产业增加值、国内生产总值空间演变整体向着均衡有序的方向发展,水—经济的空间不均衡性逐步缩小;新疆农作物水足迹显著影响其第一产业增加值空间演变,影响期1~5 a,农业经济空间分布受农业用水空间分布的长期制约;农作物水足迹和国内生产总值没有空间演变因果关系,全疆经济发展向着第二产业、第三产发展转型,农业经济不再显著影响全疆经济发展。 相似文献
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华北山区短时段参考作物蒸散量的计算 总被引:13,自引:2,他引:13
短时段参考作物蒸散量的估算是研究华北山区小尺度范围内的水分循环和转化的重要环节.因受观测条件的限制,北方半湿润半干旱山区短时段参考作物蒸散量的研究相对较少.本文利用FAO Penman-Monteith公式、FAO Penman修正式和Priestley-Taylor公式对华北山区东台沟小流域观测到的4个月的气象数据进行了逐日的参考作物蒸散量计算,结果显示,FAO Penman修正式的计算值比FAO Penman-Monteith公式的计算值平均偏大16%左右,而且经过统计分析,它们具有很好的相关性,即在代表流域内使用FAO Penman修正式计算出参考作物蒸散量之后,再乘以一个折算系数(如0.84),即可得到与FAO Penman-Monteith公式的计算值较为相近的结果;而Priestley-Taylor公式的计算值与FAO Penman-Monteith公式的计算值相比,差异比较显著.分析其原因,我们认为是由于Priestley-Taylor公式没有考虑空气动力项对参考作物蒸散量的影响.因此,如果在华北山区使用Priestley-Taylor公式计算参考作物蒸散量,必须根据季节对公式中的常数项α重新进行修正.本文通过对2003年8月~2004年8月期间逐日计算得到的ET0(P-T)和ET0(P-M)值进行对比分析后,给出了修正后的不同季节的α值,为华北山区计算作物蒸散量提供了依据. 相似文献
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基于中国绿洲喜温作物分布区67个地面气象站1960—2016年逐日平均气温数据,运用线性趋势法、反距离加权(IDW)、Morlet小波分析法、Mann-Kendall检验等方法,分析了中国绿洲喜温作物气候生长期生长初、终日及生长期的时空变化对全球变暖停滞(globe warming hiatus)的响应。结果表明:1998—2012年中国绿洲喜温作物气候生长期生长初、终日及生长期变化倾向率分别为:-2.15d·(10 a)-1、2.76 d·(10 a)-1、4.91 d·(10 a)-1,与1960—2016年和1960—1998年相比呈现出初日提前、终日推迟、生长期延长的态势,没有出现对全球变暖停滞的响应;空间变化方面,仅有超过22%的站点有对全球变暖停滞的响应,整体响应不显著;但各绿洲对全球变暖停滞的响应却不尽相同,柴达木绿洲喜温作物气候生长期对全球变暖停滞的响应最为显著,其余绿洲则反之,也反映了青藏高原是气候变化的驱动器与放大镜。突变分析显示,研究区喜温作物生长初日、终日及生长期分别在2008年、2001年、2006年发生突变,突变年份多集中于变暖停滞期,之后的变化趋势显示对全... 相似文献
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Changes and spatial patterns of eco-environment in the farming-pastoral region of northern China 总被引:1,自引:0,他引:1
This paper firstly selects 10 kinds of indexes to reflect eco-environment background condition and builds the multi-subject spatial database by using ground meteorological data, remote sensing data and DEM. It then discusses in detail the methods about evaluating eco-environment background condition and analyzing eco-environment change. The eco-environment background conditions of 1989 and 1999 are synthetically appraised. Finally, the paper analyzes the spatial distribution, quantitative change, the trend of change, the areas of change and the dynamic spatial pattern of eco-environment. The results are as follows: (1) The eco-environment background condition becomes worse from southeast to northwest in the farming-pastoral region of northern China. (2) The eco-environment background condition deteriorates from 1989 to 1999. (3) In the adjacent areas of Shanxi-Shaanxi-Inner Mongolia-Gansu-Ningxia, Horqin Sandy Land and its peripheries, and eastern Qinghai province, eco-environmental deterioration is very serious. 相似文献
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中国北方农牧交错带生态环境的空间格局演变 总被引:1,自引:0,他引:1
1 IntroductionThe scope of the farm ing-pastoral region of northern China begins from the w est of G reatH inggan M ountains, w estw ards passes through southeastern Inner M ongolia, northern H ebei,Shanxiand Shaanxi,and then reaches the O rdos Plateau.It… 相似文献
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1961-2010年中国十大流域水分盈亏量时空变化特征 总被引:6,自引:0,他引:6
采用线性回归方法和Mann-Kendall方法对1961-2010年中国和十大流域水分盈亏量的气候及变化趋势特征进行分析,并对各流域年水分盈亏量变化成因进行探讨。结果表明:1中国多年平均年水分盈亏量(1961-2010年平均)为负值,水分条件表现为亏缺。空间分布总体呈现南方盈余,向北向西水分亏缺态势。2中国水分盈亏量月变化特征表现为夏季6-8月有盈余,7月盈余量最大;其余各月为亏缺,4月亏缺量最大,十大流域月变化特征各有不同。31961-2010年,中国年水分亏缺量呈现多—少—多变化态势,1990s亏缺量为近50年来最少。2000s中国水分亏缺量较常年偏多,主要是由于大多数流域水分亏缺量偏多或盈余量偏少造成的。4近50年来,全国平均年和春夏冬三季水分盈亏量呈现增加趋势,秋季减少趋势显著。5松花江、辽河、海河、黄河流域及西南诸河年水分盈亏量呈现减少趋势,除西南诸河是由于年降水量增加速率小于蒸散量增加速率导致其减少趋势外,其它四个流域则是由于年降水量减少速率大于潜在蒸散量减少速率,年降水量减少变化趋势起主要作用;其余流域年水分盈亏量呈现增加趋势,淮河和长江流域主要是因为潜在蒸散量减少速率大于降水的减少速率,潜在蒸散量的减少变化趋势起主要作用,东南诸河、西北诸河、珠江流域由于年降水量增加、潜在蒸散量减少,二者均对水分盈亏量增加有利。 相似文献
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Spatio-temporal analysis of the geographical centroids for three major crops in China from 1949 to 2014 总被引:2,自引:1,他引:2
Lingling Fan Shefang Liang Hao Chen Yanan Hu Xiaofei Zhang Zhenhuan Liu Wenbin Wu Peng Yang 《地理学报(英文版)》2018,28(11):1672-1684
Spatial distribution changes in major crops can reveal important information about cropping systems. Here, a new centroid method that applies physics and mathematics to spatial pattern analysis in agriculture is proposed to quantitatively describe the historical centroids of rice, maize and wheat in China from 1949 to 2014. The geographical centroids of the rice area moved 413.39 km in a 34.32° northeasterly (latitude 3.08°N, longitude 2.10°E) direction at a speed of 6.36 km/year from central Hunan province to Hubei province, while the geographical centroids of rice production moved 509.26 km in the direction of 45.44° northeasterly (latitude 3.22°N, longitude 3.27°E) at a speed of 7.83 km/year from central Hunan province to Henan province. The geographical centroids of the maize area and production moved 307.15 km in the direction of 34.33° northeasterly (latitude 2.29°N, longitude 1.56°E) and 308.16 km in the direction of 30.79° northeasterly (latitude 2.39°N, longitude 1.42°E), respectively. However, the geographical centroids of the wheat area and production were randomly distributed along the border of Shanxi and Henan provinces. We divided the wheat into spring wheat and winter wheat and found that the geographical centroids of the spring wheat area and production were distributed within Inner Mongolia, while the geographical centroids of winter wheat were distributed in Shanxi and Henan provinces. We found that the hotspots of crop cultivation area and production do not always change concordantly at a larger, regional scale, suggesting that the changing amplitude and rate of each crops’ yield differ between different regions in China. Thus, relevant adaptation measures should be taken at a regional level to prevent production damage in those with increasing area but decreasing production. 相似文献
20.
中国虚拟水战略区划研究 总被引:2,自引:3,他引:2
为探究我国不同区域虚拟水研究和实践的发展方向,以国内31个省级行政区为研究单元,运用指标体系评价方法和列联表互斥的矩阵分类方法进行了我国虚拟水战略区划研究。结果表明:①依据水资源禀赋指数可以将全国划分为虚拟水输出地域、虚拟水输入地域和虚拟水平衡地域3个一级区划单元;其中,虚拟水输出地域的发展方向是提高水密集型工农业产品的商品率,虚拟水输入地域则应着手准备缩减水密集型产业,而虚拟水平衡地域则不宜进行大规模的虚拟水战略实践。②依据农产品贸易指数和非农水资源需求压力指数,将全国细分为典型输入(出)区、内部优化区、成长输入(出)区、复合型区、潜在输入(出)区和现实输入(出)区共12个二级区划单元,并指出了各二级区的产业发展方向。 相似文献