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1.
将作物水分胁迫指数(CWSI)与作物水分生产函数相结合,得到了用CWSI表示的作物水分生产 函数,进而推导出基于作物水分生产函数和CWSI的作物产量估算模式。该估算模式利用了易于获取的红外遥感 数据,克服了水分生产函数中作物蒸发蒸腾量准确资料难于获取的限制,并且通过CWSI和作物水分生产函数的 耦合使该估产方法具有一定的物理意义。经大田膜下滴灌棉花实测资料检验表明,该模型计算值的相对误差基本 保持在10%左右。 相似文献
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根据蒙自坝子中部蒙自气象站1980—2010年逐月气象资料和相应的作物数据及CROPWAT软件,计算了蒙自坝子近31年来的作物需水量和灌溉用水量,通过排频,确定了不同作物在相应保证率下的灌溉用水量。研究结果表明,水稻、玉米、马铃薯、烤烟、花生等大春作物的多年平均作物需水量分别为696.2、427.7、517.8、414.0和469.0mm,作物需水量离差系数较小。大春作物生育期有效降雨量较多,故灌溉需水量很少,但水稻因为泡田用水、秧田用水、生长期渗漏等,导致灌溉用水量很大,成为灌溉需水量最大的作物;小春作物蚕豆、小麦、油菜的多年平均作物需水量分别为394.8、412.5、476.2mm。因为生育期内有效降雨量相对较少,小春作物灌溉需水量很大;甘蔗、蔬菜为全年种植(生长)作物,作物需水量分别为1308.3和1186.9mm,灌溉需水量分别为675.2和523.51/11/1,成为仅次于水稻的第2和第3位灌溉需水量最大的作物。该研究为蒙自坝子灌溉制度制定、作物种植结构调整提供了理论依据。 相似文献
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Di WU Allan A. ANDALES Hui YANG Qing SUN Shichao CHEN Xiuwei GUO Donghao LI Taisheng DU 《农业科学与工程前沿(英文版)》2021,8(4):545-558
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作物水分信息采集技术与采集设备 总被引:1,自引:0,他引:1
随着社会经济的发展和科学技术的不断进步,农田灌溉正朝着“自动、精准”的方向发展。实现自动、精准灌溉,需要获得及时、准确的作物水分状况信息作为基本依据,而先进、可靠的采集技术与设备则是快速、准确、连续获取作物水分信息的重要保障。作物水分信息,根据其采集部位可分为土壤信息和作物信息两类;而根据采集信息所代表
表的范围,则可分为点源信息和区域信息两类。2种分类结果相组合,可以将作物水分信息分为点源土壤水分状况信息,区域土壤水分状况信息,点源作物水分状况信息和区域作物水分状况信息四大类O目前应用较多的点源土壤水分状况信息快速采集技术主要有中子仪法、时域反射法(TDR)、频域反射法(FDR)、驻波率法(SWR)和张力计法;点源作物水分状况信息的采集技术则主要有红外温度法、叶水势法、光谱法、茎变差法和蒸腾速率法;区域土壤水分状况信息的采集技术主要有遥感法(裸地表层土壤)和墒墒情监测网络法;区域作物水分状况信息则主要通过遥感方法获得,包括热红外遥感和微波遥感等方法。这些技术方法各有优点、缺点和适用范围。从目前的研究和实际应用情况看,基于土壤介电特性的土壤水分信息测量技术(TDR,FD和SWR)和基于植株蒸腾速率、植株茎直径变差和作物冠层红外温度的作物水分状况信息测量技术是具有明显优优势和良好发展潜力的点源水分信息采集技术;以TDR、FDR和SWR为基础,结合GPS和GSM/GPRS无线数据传输系统,适用于区域土壤水分信息的采集;而以热红外遥感和微波遥感为基础的系统则是大面积的区域土壤水分状况信息(裸土表层)和区域作物水分状况信息的主要采集方法。这些作物水分信息采集方法的进一步完善提高,以及相应的精度高、稳定性好、价格适中的各类传感器及配套的数据处理设备的研制将是未来作物需水信息采集领域的重点工作目标。 相似文献
表的范围,则可分为点源信息和区域信息两类。2种分类结果相组合,可以将作物水分信息分为点源土壤水分状况信息,区域土壤水分状况信息,点源作物水分状况信息和区域作物水分状况信息四大类O目前应用较多的点源土壤水分状况信息快速采集技术主要有中子仪法、时域反射法(TDR)、频域反射法(FDR)、驻波率法(SWR)和张力计法;点源作物水分状况信息的采集技术则主要有红外温度法、叶水势法、光谱法、茎变差法和蒸腾速率法;区域土壤水分状况信息的采集技术主要有遥感法(裸地表层土壤)和墒墒情监测网络法;区域作物水分状况信息则主要通过遥感方法获得,包括热红外遥感和微波遥感等方法。这些技术方法各有优点、缺点和适用范围。从目前的研究和实际应用情况看,基于土壤介电特性的土壤水分信息测量技术(TDR,FD和SWR)和基于植株蒸腾速率、植株茎直径变差和作物冠层红外温度的作物水分状况信息测量技术是具有明显优优势和良好发展潜力的点源水分信息采集技术;以TDR、FDR和SWR为基础,结合GPS和GSM/GPRS无线数据传输系统,适用于区域土壤水分信息的采集;而以热红外遥感和微波遥感为基础的系统则是大面积的区域土壤水分状况信息(裸土表层)和区域作物水分状况信息的主要采集方法。这些作物水分信息采集方法的进一步完善提高,以及相应的精度高、稳定性好、价格适中的各类传感器及配套的数据处理设备的研制将是未来作物需水信息采集领域的重点工作目标。 相似文献
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作物系数-参考作物蒸发蒸腾量法是作物需水量计算最普遍采用的方法。作物系数作为该方法的重要参数,它的确定已成为作物需水量研究的关键问题。依据2005-2007年3年田间试验资料,利用Penman-Monteith公式计算了关中地区大豆全生育期间参考作物蒸散量,并利用农田水量平衡方程及土壤水分胁迫系数计算了作物实际蒸发蒸腾量,由此计算了大豆各生育阶段的作物系数,并分析了大豆作物系数变化规律。结果表明:关中地区大豆全生育期间参考作物蒸散量平均为498.4 mm;大豆作物系数全生育期平均为0.89,在开花~结荚阶段最大,平均为1.26,其次为结荚~成熟阶段,平均为1.04,播种~幼苗阶段最小,为0.29;在关中气候背景下,大豆作物系数与>10℃积温具有较好的二次多项式关系。 相似文献
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Water Consumption and Use Efficiency of Main Crops on Semi-drought Area of Western Liaoning Province
The laws of water consumption in corn,peanuts and millet on the semi-drought area of western Liaoning Province were studied through the FAO-Penman Monteith method and the water balance method.Among three corps,the amount of the day water demand,the whole growth period water demand and the soil water deficit of corn were all the largest.At the same time,its degree of agreement between the water demand and the level of precipitation was the worst,and its average in crop coefficient was larger.The amount of th... 相似文献
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不同水分状况下红壤水稻的小量平衡和生产能力 总被引:3,自引:0,他引:3
在我国中亚热带典型红壤区通过水稻测坑试验,测定了农田水量平衡各分项。结果表明,低、中、高水分条件下早稻的蒸散需水量为368.6~415.4mm,日均蒸散量为4.29~4.83mm/d。5月~7月的降水总量可以满足早稻的蒸散和渗漏需要,并有多余的水分需排出。但由于降雨间隔不匀,仍需少量灌水来补充调节。晚稻低、中、高3种水分状况下蒸散量为334.9~384.2mm,略低于早稻,但日均蒸散量高于早稻。即 相似文献
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Yuecun Ma Hongling Qin Chunmei Yin Wangsheng Gao Hongsheng Zhang Peng Sui Yuanquan Chen Xiangdong Li 《Frontiers of Agriculture in China》2008,2(2):208-215
The dynamics of soil water content under different tillage systems was studied throughout the growing period of oat (Avena sativa L.). The treatments included tillage system (zero tillage, minimum tillage, and conventional tillage), residue cover (with
and without cover), and crop rotation (continuous cropping and crop rotation). The results indicated that soil water content
and crop water use efficiency were improved under zero tillage with cover. When crop stubble was removed, soil water content
under zero tillage was reduced, especially in the surface soil layer. Compared to conventional tillage, minimum tillage increased
soil water content and its storage, either with cover or without cover. For all the three tillage treatments, soil water content
with cover was significantly higher than that of without cover. Furthermore, soil water content and crop water use efficiency
under crop rotation was consistently higher than continuous cropping. Therefore, it is concluded that minimum tillage with
cover is the optimum management system in this area. At present, however, a combination of crop rotation and minimum tillage
is a viable option, since there are not enough crop residues available for cover of land.
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Translated from Acta Ecologica Sinica, 2007, 27(6): 2523–2530 [译自: 生态学报] 相似文献
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A. Elvanidi N. Katsoulas T. Bartzanas K. P. Ferentinos C. Kittas 《Precision Agriculture》2017,18(3):332-349
Crop water status is an important parameter for plant growth and yield performance in greenhouses. Thus, early detection of water stress is essential for efficient crop management. The dynamic response of plants to changes of their environment is called ‘speaking plant’ and multisensory platforms for remote sensing measurements offer the possibility to monitor in real-time the crop health status without affecting the crop and environmental conditions. Therefore, aim of this work was to use crop reflectance and temperature measurements acquired remotely for crop water status assessment. Two different irrigation treatments were imposed in tomato plants grown in slabs filed with perlite, namely tomato plants under no irrigation for a certain period; and well-watered plants. The plants were grown in a controlled growth chamber and measurements were carried out during August and September of 2014. Crop reflectance measurements were carried out by two types of sensors: (i) a multispectral camera measuring the radiation reflected in three spectral bands centred between 590–680, 690–830 and 830–1000 nm regions, and (ii) a spectroradiometer measuring the leaf reflected radiation from 350 to 2500 nm. Based on the above measurements several crop indices were calculated. The results showed that crop reflectance increased due to water deficit with the detected reflectance increase being significant about 8 h following irrigation withholding. The results of a first derivative analysis on the reflectance data showed that the spectral regions centred at 490–510, 530–560, 660–670 and 730–760 nm could be used for crop status monitoring. In addition, the results of the present study point out that sphotochemical reflectance index, modified red simple ratio index and modified ratio normalized difference vegetation index could be used as an indicator of plant water stress, since their values were correlated well with the substrate water content and the crop water stress index; the last being extensively used for crop water status assessment in greenhouses and open field. Thus, it could be concluded that reflectance and crop temperature measurements might be combined to provide alarm signals when crop water status reaches critical levels for optimal plant growth. 相似文献
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新疆水资源匮乏,大部分水资源用于农业,调整农作物种植结构,对于减小新疆农业用水量,优化水资源配置具有重要意义。本研究将新疆分为南疆、北疆、东疆和伊犁河谷,利用18个气象站2000-2009年的气象资料,分析三种主要作物(棉花、玉米、小麦)的蓝水蒸散量及蓝水需水量。对四个地区农作物种植结构进行调整,对比分析调整前后蓝水需水量变化。结果表明:1)基于农作物种植总面积不变原则,调整各地区农作物种植结构,全疆农作物蓝水需水量减少近2×108 m3;2)基于水资源总量控制,在"十二五"规划面积基础上调整农作物种植结构,蓝水需水量减少10.56×108 m3,全疆粮食作物玉米和小麦产量均满足规划要求,棉花产量尚需进一步提高。以蓝水蒸散量为工具,合理布局农作物种植结构,适当减小农作物种植面积,可以减少农业用水量,同时减小对农作物产量的影响。 相似文献
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基于SIMETAW模型的北京地区主要作物需水量估算 总被引:12,自引:8,他引:4
应用北京近56年气象数据对SIMETAW模型进行校正,并利用模型估算北京地区主要大田作物需水量。结果表明:SIMETAW模型对参考作物腾发量的模拟与彭曼-蒙特斯公式计算值较为接近,r>0.94,结果可靠。北京地区主要大田作物的需水量和作物系数在全生育期内均呈现单峰型曲线;果树类作物需水量相对较大,其次是粮经作物,其中春花生、棉花、春甘薯和冬小麦需水量较大,均在430 mm以上;蔬菜类作物由于生育期较短,单季耗水量小,均在400 mm以下。 相似文献
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Weili Liang Hongzhan Lü Guiyan Wang D. J. Connor G. M. Rimmington 《Frontiers of Agriculture in China》2007,1(2):155-165
Based on data collected from field experiments, a comprehensive model was built on the Ithink (a registered trademark of iSee Systems) platform to simulate the dynamics of water and nitrogen, and crop performance in
the winter wheat-summer maize double cropping system of the North China plain. The model, consisting of seven sub models,
i.e. weather generator, phenology, biomass, dry matter partitioning, water balance, nitrogen balance, and nitrogen absorption
and partitioning, well reflects water and nitrogen use and their relationship with crop yield under field conditions.
A vertical water movement equation is employed in the water balance sub model to account for movement between layers. Crop
transpiration and soil evaporation are simulated separately according to potential evaporation, crop cover and a soil water
deficit coefficient. Soil evaporation is from the surface layer only while crop transpiration comprises the total amount of
water absorbed by the root system from all soil layers.
The model considers that nitrogen transformations, transfers and uptake are fulfilled by root systems. Transformation of nitrogen
as mineralization, fixation and denitrification are responsive to soil moisture and temperature. Nitrogen movement is simulated
with a convection-dispersion equation with nitrate as the soil solute. Nitrogen absorption and partitioning sub model includes
the effects of water and nitrogen supply, crop nitrogen demand and nitrogen content in various crop organs. The model can
be used to simulate crop yield, water-and nitrogen-use efficiencies and water-nitrogen leaching to specific soil layers in
different water and nitrogen management practices. 相似文献
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根据冬小麦生长发育与土壤水分条件关系的机理研究,建立了田间条件下的土壤水分运动与作物生产耦合机理模型。该模型包括土壤水分运动子模型和作物生长发育子模型,分别模拟了棵间蒸发、根系吸水、生育期、光合、呼吸、同化物分配、根系生长、叶面积增长、产量形成等过程。用1995-10~1996-06的田间试验资料对模型进行验证,结果表明该模型能较好地模拟土壤水分运动与作物生长发育过程的耦合关系。 相似文献
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Hongzhan Lü Weili Liang Guiyan Wang David J. Connor Glyn M. Rimmington 《Frontiers of Agriculture in China》2009,3(2):109-121
The test on the model with data collected from two years’ field experiments revealed an ability to satisfactorily simulate
crop parameters such as LAI, biomass accumulation and partitioning, yield, and variables influencing crop growth and development
as nitrogen uptake by crops and partitioning in different organs, and dynamics of soil water and nitrogen including infiltration
and leaching. With the model, crop yield, water use efficiency (WUE), nitrogen use efficiency (NYE) and water-nitrogen leaching
at specific soil layers under various water and nitrogen management practices were simulated to provide data used as references
for designing sustainable nitrogen and water management practices.
The outputs of the simulated experiment with various treatments of irrigation and nitrogen application indicated that crop
yield was closely related to water and nitrogen application, crop water use was positively related to irrigation amount, and
nitrogen fertilization could improve the crop water use and WUE within certain limits. This is a valuable evidence to be considered
in water-saving farming. Nitrogen uptake had a positive relation to nitrogen application, while irrigation to some extent
improved its uptake by crops and hence increased NYE. Additionally, irrigation and fertilization had great effects on nitrogen
leaching. Thus, in order to improve WUE and NYE, the model showed how nitrogen application and irrigation should be well coordinated. 相似文献
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周勉 《扬州大学学报(农业与生命科学版)》1987,(1)
本文论述发展灌溉农业的重要性和发展途径,把作物需水量的规律作为灌溉农业的科学依据,而作物需水量又受控于气候条件,特别是受人为气候变化的影响,需要引起重视。 相似文献