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持续农业--生态农业及干旱区实践模式探究 总被引:2,自引:1,他引:2
论述了生态农业与持续农业(SARD)提出的背景及其概念,结合干旱区实例介绍,阐述了持续农业与生态农业在中国发展的趋势。 相似文献
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河南省生态农业模式设计与建设研究 总被引:2,自引:0,他引:2
生态农业建设是未来中国农业发展的大趋势,全面推广生态农业势在必行。本文根据河南省自然资源状况和地域差异规律,因地制宜地提出了全省不同生态类型区的生态农业建设、发展模式,以及生态农业建设的主要技术环节和措施。 相似文献
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长江三峡库区生态农业发展模式探讨 总被引:15,自引:0,他引:15
该文阐述三峡库区发展生态农业的意义,探讨了库区生态农业发展的目标,任务和原则,提出了库区生态农业发展的六种模式即自给型粮食种植业,优势果蔬业,生态经济型(含果,茶、桑、药等)林业,效益型畜牧业,增值型绿色产品加工业和休闲型农业(生态农业旅游业)及相应的对策建议。 相似文献
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本文通过分析东庄营村农业系统的现状,根据系统结构决定系统功能的原则,利用生态经济平衡的原理,寻求农业系统最佳结构模式,以求土地资源利用充分、合理,农业系统结构趋于合理,系统功能改善,生态经济效益显著提高。 相似文献
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黄河三角洲湿地生态特征变化及可持续性管理对策 总被引:54,自引:10,他引:54
近年来,由于农业市场化和产业化的发展,工业与城市化的崛起,黄河三角洲湿地生态特征发生了巨大变化。表现在湿地类型和面积的改变,湿地水状况及水质的变化,湿地产品的不可持续利用等,通过对湿地生态变化的自然因素和人为原因进行分析,提出了黄河三角洲湿地可持续性管理的方案,并从生态、社会、经济指标出发,探讨了湿地可持续性管理对策。 相似文献
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There are typical ecosystems of littoral wetlands in the Yellow River Delta. In order to study the relationships between Tamarix chinensis and environmental variables and to predict T. chinensis potential distribution in the Yellow River Delta, 641 vegetation samples and 964 soil samples were collected in the area in October of 2004, 2005,2006 and 2007. The contents of soil organic matter, total phosphorus, salt, and soluble potassium were determined.Then, the analyzed data were interpolated into spatial raster data by Kriging interpolation method. Meanwhile, the digital elevation model, soil type map and landform unit map of the Yellow River Delta were also collected. Generalized Additive Models (CAMs) were employed to build species - environment model and then simulate the potential distribution of T. chinensis.The results indicated that the distribution of T. chinensis was mainly limited by soil salt content, total soil phosphorus content, soluble potassium content, soil type, landform unit, and elevation. The distribution probability of T. chinensis was produced with a lookup table generated by Grasp Module (based on GAMs) in software Arc View GIS 3.2. The AUC (Area Under Curve) value of validation and cross - validation of ROC (Receive Operating Characteristic) were both higher than 0.8, which suggested that the established model had a high precision for predicting species distribution. 相似文献
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近、现代黄河三角洲地貌形态反演 总被引:5,自引:0,他引:5
1855年黄河改夺大清河河道后于山东利津县东北入海。至今黄河尾癌河道历经10次大的改道变迁,塑造了近、现代黄河三角洲,形成了7个主要的亚三洲堆积体。该文利用黄河尾癌河道改道资料,近、现代河口流路变迁图,近、现代黄河三角洲体系图以及1985-1986年的水文工程地质钻孔资料,在研究黄河三角洲沉积模式的基础上,对工程地质钻孔数据进行沉积层序分析,将今论古,反推近、现代黄河三角洲沉积地貌,研究结果近似展示了近、现代黄河三角洲二维平面的发育演变和其时其地的地貌形态。 相似文献
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基于GIS的黄河三角洲盐碱地改良分区 总被引:41,自引:0,他引:41
黄河三角洲盐碱地面积超过总面积的70%,而盐碱地改良分区是因地制宜,综合治理盐域地的前提,通过综合运用地理信息系统的各种空间数据分析功能,将黄河三角洲土地盐碱化现状分为:非盐碱地,轻度盐碱地,中度盐碱地,重度盐碱地,滩涂5个区,并结合地下水长期观测资料,进行成因分析,建立了黄河三角洲盐碱地改良分区模型,立足土地盐碱化的现状,充分考虑地下水埋深和矿化度,把黄河三角洲盐碱地按改良难易程度分为:易改良区,较难改良区,难改良区,近期不宜作改良区,并针对不同的盐碱地改良区提出了相应的土壤改良对策。 相似文献
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Evapotranspiration (ET) is an important parameter for water resource management. Compared to the traditional ET computation and measurement methods, the ET computation method based on remote sensing has the advantages of quickness, precision, raster mapping and regional scale. SEBAL, an ET computation model using remote sensing method is based on the surface energy balance equation which is a function of net radiance flux, soil heat flux, sensible heat flux and latent heat flux. The former three fluxes can be computed through the parameters retrieved from remote sensing image, then the latent heat flux can be obtained to provide energy for ET. Finally we can obtain the daily ET. In this study SEBAL was applied to compute ET in the Yellow River Delta of China where water resource faces a rigorous situation. Three Landsat TM images and meteorology data of 1999 were used for ET computation, and spatial and temporal change patterns of ET in the Yellow River Delta were analysed. 相似文献
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黄河三角洲农作物种植分区的遥感研究 总被引:9,自引:0,他引:9
本文选取了一年中三个不同时相的TM影像,分别求出了三幅影像的NDVI分布图,将其合成为一幅影像图。由于不同区域种植的作物在三个时相中的NDVI变化是不同的,因此在NDVI合成图上会呈现不同的颜色区域。通过对不同颜色区域进行采样分析,可以确定桃红色区域为冬小麦、玉米(大豆)轮作区,蓝紫色区域为棉花、春玉米、杂粮种植区,亮蓝区域为水稻种植区,亮绿色区域为林地、草地。最后,根据不同颜色区域的NDVI变化特征用非监督分类和监督分类相结合的方法对影像进行了分类提取。这样便可对黄河三角洲农作物的种植情况进行宏观的了解,为农作物种植合理布局及农业可持续发展提供依据。 相似文献
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海峡西岸经济区与长三角、珠三角经济区产业同构化的实证研究 总被引:4,自引:0,他引:4
产业同构化是目前国内各大经济区产业升级优化和彼此合作发展的瓶颈之一。选定海峡西岸经济区,长三角和珠三角经济区为研究对象,从三次产业、工业和第三产业内部结构3个方面着手,应用相似系数这一指标,分别从静态与动态的角度着重分析海西区/珠三角区和海西区/长三角区的产业同构的现状与变化,并在此基础上,依据分形理论中的R/S分析方法,预测其产业同构化的未来发展趋势,期望能够为海西区确定未来经济发展的合理方向和产业结构调整的原则提供理论依据。 相似文献
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Evapotranspiration (ET) is an important parameter for water resource management. Compared to the traditional ET computation and measurement methods, the ET computation method based on remote sensing has the advantages of quickness, precision, raster mapping and regional scale. SEBAL, an ET computation model using remote sensing method is based on the surface energy balance equation which is a function of net radiance flux, soil heat flux, sensible heat flux and latent heat flux. The former three fluxes can be computed through the parameters retrieved from remote sensing image, then the latent heat flux can be obtained to provide energy for ET. Finally we can obtain the daily ET. In this study SEBAL was applied to compute ET in the Yellow River Delta of China where water resource faces a rigorous situation. Three Landsat TM images and meteorology data of 1999 were used for ET computation, and spatial and temporal change patterns of ET in the Yellow River Delta were analysed. 相似文献