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1.
无人机遥感技术在精量灌溉中应用的研究进展 总被引：4，自引：0，他引：4
以提高农业用水效率为目标的精量灌溉是未来农业灌溉的主要模式,精量灌溉的前提条件是对作物缺水的精准诊断和科学的灌溉决策。用于作物缺水诊断和灌溉决策定量指标的信息获取技术主要基于田间定点监测、地面车载移动监测及卫星遥感。无人机从根本上解决了卫星遥感由于时空分辨率低而导致的瞬时拓延、空间尺度转换、遥感参数与模型参数定量对应等技术难题,也克服了地面监测效率低、成本高、影响田间作业等问题。近几年的研究结果表明,无人机遥感系统可以高通量地获取多个地块的高时空分辨率图像,使精准分析农业气象条件、土壤条件、作物表型等参数的空间变异性及其相互关系成为可能,为大面积农田范围内快速感知作物缺水空间变异性提供了新手段,在精量灌溉技术应用中具有明显的优势和广阔的前景。无人机遥感系统已经应用在作物覆盖度、株高、倒伏面积、生物量、叶面积指数、冠层温度等农情信息的监测方面,但在作物缺水诊断和灌溉决策定量指标监测方面的研究才刚刚起步,目前主要集中在作物水分胁迫指数(CWSI)、作物系数、冠层结构相关指数、土壤含水率、叶黄素相关指数(PRI)等参数估算的研究,有些指标已经成功应用于监测多种作物的水分胁迫状况,但对于大多数作物和指标,模型的普适性还有待进一步研究。给出了无人机遥感在精准灌溉技术中应用的技术体系,并指出,为满足不同尺度的高效率监测和实现农业用水精准动态管理的需求,今后无人机遥感需要结合卫星遥感和地面监测系统,其中天空地一体化农业水信息监测网络优化布局方法与智能组网技术、多源信息时空融合与同化技术、作物缺水多指标综合诊断模型、农业灌溉大数据等将是未来重点研究内容。 相似文献
2.
《Agricultural Water Management》2006,79(1):1-27
The monitoring of crop production and irrigation at a regional scale can be based on the use of ecosystem process models and remote sensing data. The former simulate the time courses of the main biophysical variables which affect crop photosynthesis and water consumption at a fine time step (hourly or daily); the latter allows to provide the spatial distribution of these variables over a region of interest at a time span from 10 days to a month. In this context, this study investigates the feasibility of using the normalised difference vegetation index (NDVI) derived from remote sensing data to provide indirect estimates of: (1) the leaf area index (LAI), which is a key-variable of many crop process models; and (2) crop coefficients, which represent the ratio of actual (AET) to reference (ET0) evapotranspiration.A first analysis is performed based on a dataset collected at field in an irrigated area of the Haouz plain (region of Marrakesh, Central Morocco) during the 2002–2003 agricultural season. The seasonal courses of NDVI, LAI, AET and ET0 have been compared, then crop coefficients have been calculated using a method that allows roughly to separate soil evaporation from plant transpiration. This allows to compute the crop basal coefficient (Kcb) restricted to the plant transpiration process. Finally, three relationships have been established. The relationships between LAI and NDVI as well as between LAI and Kcb were found both exponential, with associated errors of 30% and 15%, respectively. Because the NDVI saturates at high LAI values (>4), the use of remotely-sensed data results in poor accuracy of LAI estimates for well-developed canopies. However, this inaccuracy was not found critical for transpiration estimates since AET appears limited to ET0 for well-developed canopies. As a consequence, the relationship between NDVI and Kcb was found linear and of good accuracy (15%).Based on these relationships, maps of LAI and transpiration requirements have been derived from two Landsat7-ETM+ images acquired at the beginning and the middle of the agricultural season. These maps show the space and time variability in crop development and water requirements over a 3 km × 3 km irrigated area that surrounds the fields of study. They may give an indication on how the water should be distributed over the area of interest in order to improve the efficiency of irrigation. The availability, in the near future, of Earth Observation Systems designed to provide both high spatial resolution (10 m) and frequent revisit (day) would make it feasible to set up such approaches for the operational monitoring of crop phenology and irrigation at a regional scale. 相似文献
3.
Ruth Meinzen-Dick 《Irrigation and Drainage Systems》1995,9(4):371-387
Despite considerable discussion of the importance of timeliness as a key dimension of irrigation performance, few studies have assessed how well irrigation systems deliver timely water supplies, nor the magnitude of the effect on agricultural production. This paper lays out indicators of timeliness of irrigation supply which distinguish between deliveries which meet crop needs, and surplus water supplies which cannot be used by crops. These indicators are then applied to empirical data from the Sone Irrigation System of Bihar, India. Using these indicators in an analysis of the contribution of irrigation to rice production shows that incorporating measures of timeliness explains much more of the variability in agricultural production than do simple measures of total water applications over a season. Results of production functions show that if water deliveries cannot be matched with crop requirements, they have a negative, rather than a positive, impact on yields. Water scarcity has the greatest adverse impact in production in the middle of the season, while surpluses are most damaging at the beginning and end of the season. Temporal redistribution from surplus periods to times of water scarcity therefore offers considerable scope to increase productivity without increasing water use.An earlier version of portions of this paper was presented at the IFPRI/ICAR Workshop on Agricultural Growth in India: A Review of Research Findings, 1–6 May 1994 in New Delhi. 相似文献
4.
High-resolution daily evapotranspiration (ET) maps would greatly improve irrigation management. Numerous ET mapping algorithms have been developed to make use of thermal remote sensing data acquired by satellite sensors. However, adoption of remote sensing-based ET maps for irrigation management has not been feasible due to inadequate spatial and temporal resolution of ET maps. Data from a coarse spatial resolution image in agricultural fields often cause inaccurate ET estimation because of a high level of spatial heterogeneity in land use. Image downscaling methods have been utilized to overcome spatial and temporal scaling issues in numerous remote sensing applications. In the field of hydrology, the image downscaling method has been used to improve spatial resolution of remote sensing-based ET maps for irrigation scheduling purposes and thus improves estimation of crop water requirements. This paper (part I) reviews downscaling methods to improve spatial resolution of land surface characteristics such as land surface temperature or ET. Each downscaling method was assessed and compared with respect to their capability of downscaling spatial resolutions of images. The companion paper (part II) presents review of image fusion methods that are also designed to increase spatial resolutions of images by integrating multi-spectral and panchromatic images. 相似文献
5.
Local infiltration tests on 1.5 m long blocked furrows were carried out on a loam soil to assess N fertiliser leaching under furrow irrigation where ridging operations entails placing nitrogen on the upper part of the ridge. This article focuses on the impact of flow depths, or water application depth (WAD), on nitrogen movement in seven 1.5-m long blocked furrows. For a first irrigation event, a WAD greater than or equal to 240 mm, significantly reduced the heterogeneity of the N concentration profiles measured at the top of the ridge and beneath the furrow. The virtually homogeneous N soil distribution with depth permitted the determination of the nitrogen balance throughout the season using soil samples obtained at the beginning and end of the season as well as the determination of nitrogen present in the crop tissue. This is not possible when there is a heterogeneous N soil profile at the end of the irrigation season, as observed under moderate WAD conditions. In addition, a substantial WAD delivered during the first irrigation event, and at a period where the plant N requirements are high, does not affect crop yield potential. 相似文献
6.
丘陵地区蓝莓园智能灌溉决策系统设计 总被引：2，自引：0，他引：2
针对丘陵地区蓝莓园灌溉过程中水资源浪费严重、劳动力严重短缺的问题,基于物联网技术,研究并设计了一套智能灌溉决策系统。系统包括信息采集模块、无线通信模块、智能决策模块和灌溉执行模块。信息采集模块通过布设的土壤水分传感器和小型气象站实时采集蓝莓园土壤墒情信息和环境信息（风速、降雨量、温度、湿度）;无线传输模块将信息采集模块采集到的数据实时发送到服务器端进行分析处理,并将智能决策模块的计算结果传送给灌溉执行模块;智能决策模块中,基于前期采集的历史数据使用彭曼公式和土壤水平衡公式建立灌溉决策模型,实现蒸腾量和灌溉量的计算以及实时监控与报警,该模型可根据实时获取的数据,确定是否需要灌溉及最优的灌溉量;灌溉执行模块根据接收到的灌溉信息及实际的灌溉速度计算灌溉时间,进行远程灌溉;以Visual Studio软件为平台,设计了系统上位机的监控界面,可实现土壤和环境参数的实时检测和存储、作物需水状况的分析管理以及实时预警和灌溉决策。试验结果表明,该智能灌溉决策系统可在无人干预的情况下,根据传感器采集的信息自行判断作物需水情况,当系统认为作物需要灌溉时自行驱动灌溉装置完成灌溉,从而实现蓝莓园的远程精确灌溉,节省了人力物力,有效提高了灌溉水的利用率。 相似文献
7.
随着信息技术的发展,3S技术的应用,使农业生产更加信息化。在我国,3S技术在农业领域取得了长足的发展,被广泛应用于现代农业中,包括作物估产、长势检测、气象和病虫害预报、精细施肥、灌溉等,特别以精准农业为典型代表。本文就3S技术在我国农业领域的应用现状进行介绍,提出在我国农业领域发展适合国情的3S技术,重视人才的培养,注重发挥资源优势,以市场需求为导向,依靠科技带动经济效益提高的发展方向,为我国农业生产信息化提供参考。 相似文献
8.
L.C. Guerra A. Garcia y Garcia J.E. Hook K.A. Harrison D.L. Thomas D.E. Stooksbury G. Hoogenboom 《Agricultural Water Management》2007
In Georgia and many other southeastern states in the USA, the amount of water used by agriculture for irrigation is largely unknown due to the lack of reporting requirements. Recent droughts and a water dispute with the neighboring states that include Alabama and Florida have highlighted the need for an accurate estimate of water use by agriculture. The goal of this study was to evaluate the use of a crop simulation model combined with kriging for estimating the spatial distribution of the monthly irrigation water use for cotton in the Coastal Plain region of Georgia. Farmers’ monthly irrigation applications for cotton during the 2002 and 2003 growing seasons were obtained from selected sites of the Agricultural Water Pumping program. We selected 80 fields for 2002 and 51 fields for 2003. For each of these fields, we used the Cropping System Model-CROPGRO-Cotton to simulate farmers’ irrigation applications. Ordinary kriging was used to estimate the spatial distribution of monthly total irrigation in the region. We then compared the spatial and temporal distribution of irrigation amounts predicted by the Cropping System Model-CROPGRO-Cotton with the amount of water that the farmers actually applied. The Cropping System Model-CROPGRO-Cotton simulated the temporal pattern of irrigation applications very well during the growing season. The root mean square error (RMSE) between observed and simulated total irrigation for different months ranged from 5 to 23 mm in 2002 and from 2 to 14 mm in 2003. The RMSE values were generally higher in 2002 when the irrigation applications across the region were more variable when compared with 2003. Consequently, a better agreement on the spatial distribution of monthly total irrigation for the observed and simulated was obtained for 2003 than for 2002. 相似文献
9.
10.
灌水模式对油葵耗水量产量及经济效益的影响 总被引：2，自引：0，他引：2
通过5种灌水处理模式和对照旱地油葵田间试验,探讨了灌水模式对油葵耗水量、产量、水分利用效率以及经济收入的影响。结果表明,油葵出盘前和灌浆后耗水量比其他时段多50％以上。在油葵不同生育阶段耗水量随着灌水量增加而增加;灌水定额120mm,灌两次水的灌水模式的产量最高,为2268kg／hm^2,而水分利用效率最大值出现在灌水定额66mm的灌水模式,灌水量增加反而使水分利用效率下降。经济分析结果表明,纯收入最高值出现在灌水模式93mm灌二水的处理,为2871元／hm^2,灌水定额增加或减少均导致经济收入下降。统计分析结果表明,干旱年份（全生育期有效降水量123mm）灌二水时,为了兼顾产量、水分利用效率以及经济收入,油葵最佳总灌水量以208-218mm为宜。全生育期有效降水量超过350mm的丰水年份不应该再灌水。 相似文献
11.
The problem of real-time irrigation scheduling under limited water supply is considered. The goal is to develop an irrigation operation policy which maximizes crop yields and is responsive to current season changes in weather and other variables. Because irrigation decisions are sequential and dependent on crop and soil water status, and also because crop yields can only be known at the end of the season, the decisions are arrived at by a two-stage process. In the first or the design stage, irrigations are planned for the entire season at weekly intervals using historical data and an optimal irrigation scheduling model. In the second stage, the decisions for the subsequent weeks are revised each week after updating the status of the system with real time data up to that week and solving the irrigation optimization model once again for the new conditions. Thus, each week an irrigation decision is made, the entire planning horizon is kept in view. The procedure is illustrated by application to a case study. 相似文献
12.
随着我国设施农业的快速发展,越来越多的工程技术应用到设施农业中。水肥一体化技术是集合施肥与灌溉配套使用的一项新技术,在我国农业生产中,提高水肥利用效率是设施农业生产中必须解决的问题。传统农业中常采用地表上滴灌,存在管道老化、灌溉过程中存在沿程渗漏和蒸发等问题,本研究改变传统地表滴灌形式,采用地表下埋管,地表上肥料罐将水肥混合后通过滴灌管道直接输送到作物根部的灌溉方式。同时,采用传感器进行灌溉的自动控制与自动检测土壤水分信息和肥料信息,利用远程控制来实现数据传输,并通过模拟计算出灌溉计划,大大提高了灌溉施肥自动化水平。 相似文献
13.
Effect of improved cultural practices on crop yield and soil salinity under relatively saline groundwater applications 总被引：2，自引：0，他引：2
The salinity in the root zone increases with the application of relatively saline groundwater. Therefore, a limited water
supply coupled with high pumping cost and salinity hazards, makes it more important than ever that irrigation water be used
efficiently and judiciously. In the present study, farmer's practices of irrigation application methods (Field 1) were compared
with the water saving techniques (Field 2) for crop yield and salinization for two years with maize–wheat–dhanicha cropping
pattern. For maize crop, regular furrow method of irrigation was used in Field 1 and alternate furrow method of irrigation
was used in Field 2. For wheat experiments, basin irrigation method of water application was compared with bed and furrow
method. For dhanicha, basin irrigation was applied in both the fields. The results showed that about 36% water was saved by
applying irrigation water in alternate furrows in each season without compromising the maize crop yield. The salt accumulation
in root zone in alternate furrow field was less than that in regular furrow field. The salinity level near the surface increased
substantially in both the fields. The water saving in wheat crop under bed and furrow was 9–12% in both seasons. The salinization
process in both fields during wheat crop was almost same except redistribution of salts throughout the root zone in basin
field of wheat. The salinity developed in root zone during two major growing seasons was leached in monsoon. 相似文献
14.
农作物的苗期生长是一个复杂的生理生化及代谢过程,苗期的生长发育直接影响到作物的生物产量、经济产量、营养品质及其安全性。农作物苗期长势监测对于作物肥水管理、病虫害防治具有指导作用,是精细农业和数字农业的关键技术之一。该文从农作物苗期生长形态检测、营养组分检测和病虫害诊断3个方面,详细阐述了各种无损检测技术,如机器视觉技术、激光漫反射技术、荧光测量技术和反射光谱分析技术等在作物苗期长势监测中的应用进展。国内外学者对上述技术进行了较深入的理论方法研究,部分技术已在实践中得到广泛应用,但目前作物无损检测技术大多强调单一信息的获取及分析,随着数字农业和智慧农业的发展,未来将更加强调多源、多尺度数据的获取及形态、养分、病虫害综合信息的提取。作物苗期长势的监测数据将与精准农业的联系更加紧密,为农事操作提供传感信息,形成智能化的农业施工、调优栽培与管理决策系统。 相似文献
15.
Alfonso Calera Belmonte Anne M. Jochum AndrÉs Cuesta GarcÍa Amelia Montoro Rodríguez Prudencio López Fuster 《Irrigation and Drainage Systems》2005,19(3-4):337-353
Irrigation Advisory Services (IAS) are the natural management instruments to achieve a better efficiency in the use of water
for irrigation. IAS provide the farmers with irrigation scheduling information, based on crop water requirements for different
crops, and thus, help farmers to optimise production and cost-effectiveness. Current IAS rely on labour- and cost-intensive
field work, yet are unable to cover each plot in large areas at regular short time intervals. Earth observation (EO) is naturally
destined to fill this gap. It allows for efficiently monitoring crop water requirements and related parameters within each
field in extended areas. The incorporation of IT in the generation and distribution of information makes that information
easily available to IAS and to its associated farmers in a personalised way. Farmers can opt to receive a wide variety of
products, tailored to their needs and infrastructure, ranging from simple irrigation scheduling recommendation (irrigation
volume, time) to colour-coded images (providing quick intuitive information on the crop vigour within their plots), both on
PC and/or mobile phones.
This work is based on the project DEMETER (DEMonstration of Earth observation TEchnologies in Routine irrigation advisory
services), which assesses and demonstrates the EO- and IT-induced improvements in IAS day-to-day operations. This paper describes
the methodology and discusses examples of products. 相似文献
16.
陇东旱塬休闲期农田雨水收集及补灌技术研究 总被引：2，自引：0，他引：2
在陇东旱塬休闲期农田采用集流场收集天然降水,富集叠加于农田作物可有效提高单住面积产量和总产量,抗逆减灾。收集的雨水应按照作物灌溉制度,以圆艺作物为主要供水对象,大田作物上补灌应以稀植作物为主,密植作物为辅。同时,集流场雨季集流后,翌年可用于适雨型作物种植。 相似文献
17.
基于信息融合的农业自主车辆障碍物检测方法 总被引：3，自引：0，他引：3
针对单一传感器在智能车辆环境感知中的局限性,提出一种基于摄像机与激光雷达信息融合的农业自主车辆前方障碍物检测方法。对单目摄像机获取的图像进行基于Ft（Frequency-tuned）算法的显著性检测,并生成显著图。同时对激光雷达反射点进行基于数据关联性评估的聚类分析,确定障碍物数量、边界与位置等先验信息。然后以激光雷达坐标相对应的图像像素坐标为种子点,由种子点激活经过处理的显著图,基于受限区域生长实现障碍物区域分割。试验结果表明,基于Ft算法的图像显著性检测具有更好的边缘检测效果,基于种子点的受限区域生长法可以有效地进行障碍物分割。在机器视觉的基础上融入激光雷达数据,可以更好地排除非障碍物的干扰,实现了障碍物的完整检出。 相似文献
18.
Pedroza Hector Quiones Helene Unland Waldo Ojeda Ernesto Sifuentes 《Agricultural Water Management》1999,40(2-3):333-339
In Mexico most of the agricultural production originates from large irrigation districts in the northern part of the country. This region is characterized by its semiarid desert climate with a winter rainy season dominated by frontal storms, and a summer monsoon season dominated by highly localized convective storms, yielding most of the annual precipitation. Essentially all irrigation needs must be met by surface water stored in various reservoirs. Precipitation is, therefore, the most important limiting factor in Mexico's agricultural production. Traditionally, long-time averages of statistical climate data from few and widely-spaced weather stations were used to determine frequency and amount of water applied, and the algorithms employed usually did not consider the effects of great spatial climate variability and plant physiology. In the past five years, great parts of Mexico, especially in the North, have been affected by severe water shortages resulting from insufficient precipitation (perhaps related to the ‘El Niño' phenomenon), combined with inefficient water resources management. Irrigation districts increasingly have to deal with the considerable uncertainty in water resources availability as a limiting factor in the decision making process. In order to address these irrigation water shortages, the Mexican National Water Commission and the Mexican Water Resources Institute are introducing new technologies using agrometeorological networks for more efficient, real-time irrigation scheduling in the main irrigation districts of Mexico. Validation plots established in one particular irrigation district (Carrizo Valley, Sinaloa), demonstrate water savings in the order of at least 20% without any appreciable decrease in crop yields. 相似文献
19.
L. A. Gurovich 《Irrigation Science》1979,1(2):97-105
Summary The economic impact of improved irrigation practice was studied for a number of years in a research project carried out in Central Chile on commercial fields of eleven orchard, field, vegetable and forage crops. The cost of implementing improved irrigation practice specific to a given soil-climate and crop combination, and the benefits obtained through that technology were evaluated with respect to yield increases and savings in water and crop production costs.Semi-permanent irrigation plots were established in different locations in the Central Zone of Chile (Fig. 1). At each site, the field crops were grown in crop rotations for a number of years. Several methods of irrigation were tested, using different frequencies and depths of water application.Crop yields on plots with improved irrigation practice averaged 25% more than on plots on which irrigation was applied, according to traditional farmer practice. A significant increase in consumptive water use by the crop was found with improved irrigation practice, but the total water applied during the growing season was about half of the volume applied in traditional irrigation practice.The results suggest that in developing countries with a comparatively extensive irrigation tradition, little sophistication is needed to improve irrigation practice and obtain a significant economic impact on crop production. 相似文献
20.
自动化灌溉控制工程技术的研究与应用 总被引：9，自引：0，他引：9
现代化农业对作物生长微环境要求高,对灌水时间、灌水量、灌水部位、水肥营养供给等都有更精确要求,自动化灌溉控制工程技术正是支撑现代化农业的一项基础性技术措施.为此,山东省水科院技术人员,经过多年来的技术开发与工程实践,集成电子信息技术、远程测控网络技术、计算机控制技术及信息采集处理技术,通过计算机通用化和模块化的设计程序,构筑供水流量、压力、土壤水分、作物生长信息、气象资料的自动监测控制系统,进行水、土环境因子的模拟优化,实现灌溉节水、作物生理、土壤湿度等技术控制指标的逼近控制,从而将农业高效节水的理论研究提高到现实的应用技术水平。该项技术已针对山东省不同种植作物、不同灌溉措施进行了系列推广,逐步形成了一套成熟的完整的应用技术体系。 相似文献