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中国农业地质研究及其成效 总被引:2,自引:0,他引:2
论述了中国土壤质量和农作物优质高产与土壤环境中化学元素N、P、K、S、Fe、MR、Cu、ZB、B、Mo、V、Sr、Ti、Mg、La、Ce、Pr、Nd、Sm、Eu、Y、Gd、Tb、Dy、Ho、Er、Tm、Yb、Lu、Ga、Co、Ni、F、Tl、Si、Na、Cr、Pb、Cd、Hg、Se、Ba、Te、Ta及有机质、酸碱度、含水量、含盐量有密切的关系。提出了农业地质研究的目的、内容、方法及管理。 相似文献
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The monitoring of different crops (cultivated plots) and types of surface (bare soils, etc.) is a crucial economic and environmental issue for the management of resources and human activity. In this context, the objective of this study is to evaluate the contribution of multispectral satellite imagery (optical and radar) to land use and land cover classification.Object-oriented supervised classifications, based on a Random Forest algorithm, and majority zoning post-processing are used. This study emerges from the experiment on multi-sensor crop monitoring (MCM'10, Baup et al., 2012) conducted in 2010 on a mixed farming area in the southwest of France, near Toulouse. This experiment enabled the regular and quasi-synchronous collection of multi-sensor satellite data and in situ observations, which are used in this study. 211 plots with contrasting characteristics (different slopes, soil types, aspects, farming practices, shapes and surface areas) were monitored to represent the variability of the study area. They can be grouped into four classes of land cover: 39 grassland areas, 100 plots of wheat, 13 plots of barley, 20 plots of rapeseed, and 2 classes of bare soil: 23 plots of small roughness and 16 plots of medium roughness. Satellite radar images in the X-, C- and L-bands (HH polarization) were acquired between 14 and 18 April 2010. Optical images delivered by Formosat-2 and corresponding field data were acquired on 14 April 2010.The results show that combining images acquired in the L-band (Alos) and the optical range (Formosat-2) improves the classification performance (overall accuracy = 0.85, kappa = 0.81) compared to the use of radar or optical data alone. The results obtained for the various types of land cover show performance levels and confusions related to the phenological stage of the species studied, with the geometry of the cover, the roughness states of the surfaces, etc. Performance is also related to the wavelength and penetration depth of the signal providing the images. Thus, the results show that the quality of the classification often increases with increasing wavelength of the images used. 相似文献
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北京市生态农业地质及其前景 总被引:2,自引:0,他引:2
论述了北京市土壤元素含量和农作物优质高产与土壤环境中化学元素有密切的关系。提出了生态农业地质研究的目的、内容、方法、管理及其前景。 相似文献
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对彭州市平坝地区在秋季水稻收获后,小麦播种前这一时段进行了光热水资源的农业气候分析,为种植与资源相适应的农作物、合理利用农业气候资源提供了依据。 相似文献
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The research progress of climate suitability at home and abroad was briefly reviewed in this paper, which was divided into three stages: The initial stage of research, the initial development and application stage, and the application research warming stage. The main achievements and progress of climate suitability in China were also introduced from three aspects as follows: Improvement of climate suitability model, extension of climate suitability applications and development of climate suitability model. Based on the impact of climate change on agriculture and the weak links in climate suitability research, the focus and hotspot of future climate suitability research were proposed, which will be five important directions:The climate suitability model proceed from crop growth model, the climate suitability research proceed from characteristic agriculture, the climate suitability research proceed from climate change, the climate suitability model based on different theories and the climate suitability evaluation index research. 相似文献
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气候适宜度国内外研究进展及展望 总被引:1,自引:0,他引:1
简要概述了国外在气候适宜度方面的研究现状,回顾了我国在气候适宜度方面的研究历程,将气候适宜度研究划分为3个阶段:研究的起步阶段、初步发展应用阶段及应用研究升温阶段。从气候适宜度模型的改进、气候适宜度应用的延伸及气候适宜度模型的发展3个方面介绍了我国在气候适宜度方面的主要成果和进展;从气候变化对农业的影响角度及气候适宜度研究存在的薄弱环节等方面,提出立足作物生长模型的气候适宜度模型研究、立足特色农业的气候适宜度研究、立足气候变化的气候适宜度研究、立足不同理论的气候适宜度模型研究和气候适宜度评价指标研究等方面将是未来气候适宜度研究的重点和热点。 相似文献
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CO2和O3浓度倍增对作物影响的研究进展 总被引:14,自引:0,他引:14
文中利用自行设计的OTC - 1型开顶式气室进行了 9a的田间试验 ,取得了一批质量可靠的试验数据 ,分析了CO2 浓度倍增对大豆、冬小麦、棉花、玉米、春小麦和谷子的生物量、产量及品质的影响 ,结果表明CO2 浓度倍增对上述 6种作物的生物量及产量的影响均是正效应 ,对冬小麦、棉花和谷子品质的影响可能是有利的 ,对玉米品质的影响可能是不利的 ,对大豆的影响不大 ;分析了O3 浓度倍增对冬小麦、水稻、油菜和菠菜生物量、产量及品质的影响 ,结果表明O3 浓度倍增对上述 4种作物生物量的影响均是负效应 ,对冬小麦和水稻的产量影响是负效应 ,但是冬小麦和水稻籽粒中粗蛋白和 17种氨基酸含量都有所增加 ;分析了CO2 和O3 浓度复合倍增对大豆生物量、产量及品质的影响 ,结果是生物量和产量呈增加趋势 ,说明了CO2 的正效应大于O3 的负效应。采用作物模型数值模拟方法 ,分析了CO2 和O3 浓度倍增对冬小麦生物量及产量的影响。 相似文献