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1.
The paper proposes a geostatistical approach for delineating management zones (MZs) based on multivariate geostatistics, showing the use of polygon kriging to compare durum wheat yield among the different MZs (polygons). The study site was a durum wheat field in southern Italy and yield was measured over three crop seasons. The first regionalized factor, calculated with factorial cokriging, was used to partition the field into three iso-frequency classes (MZs). For each MZ, the expected value and standard deviation of yield were estimated with polygon kriging over the three crop seasons. The yield variation was only in part related to soil properties but most of it might be ascribable to different patterns of meteorological conditions. Both components of variation (plant and soil) in a cropping system should then be taken into account for an effective management of rainfed durum wheat in precision agriculture. The proposed approach proved multivariate Geostatistics to be effective for MZ delineation even if further testing is required under different cropping systems and management. 相似文献
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Cranberry harvesting methods give only one yield value per field making characterization of within-field variation, the usual first step in precision farming, difficult. Time-consuming berry count yield and fruit rot estimations are the best “ground truth” indication of yield variation within fields. Correlations and coincidence of binary classifications based on less expensive methods such as enhanced vegetation index (EVI) from imagery, and area to point (AtoP) kriging of useable, poor quality and trash yields were compared with this “ground truth”. In general AtoP kriged values gave higher correlations and kappa statistic values with berry counts and fruit rot than EVI. Geostatistical disaggregation of per field yield totals using AtoP kriging with EVI as an external drift (AtoPKED) was also investigated. Factorial kriging was used to separate the several scales of variation in “ground truth” and EVI data and determine which ones were most spatially coherent/manageable and which related best to the AtoP kriged data. The spatial trend component of pre-harvest berry counts and AtoP kriging of yields both gave a good initial definition of spatially coherent, relatively permanent management zones. They were related to topography and depth of water table in the soil which are key factors governing cranberry yield. AtoP kriging or AtoPKED are recommended for defining management zones as they are less expensive than berry counts. The value of AtoP kriging to precision farmers for other crops to map soils at the farm scale with some imagery and just one bulked soil sample per field or use nutrient levels associated with each polygon of traditional soil survey maps is discussed in the conclusions. 相似文献
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By accounting for spatial variation in soil N levels, variable-rate fertilizer application may improve crop yield and quality, and N use efficiency within fields. The main purpose of this study was to demonstrate how site-specific wheat yield and protein data, and a geographic information system may be used in developing precision N-recommendations for spring wheat. The three steps in the procedure include: (1) estimate the amount of N-removed in wheat in the year in which the crop is harvested, (2) estimate the N-deficit, defined as the amount of additional N needed for raising protein concentration in a future crop to a specified target level, and (3) estimate the total N-recommendation by summing the mapped values of the N-removed and the N-deficit. A map for variable-rate application of fertilizer is derived by specifying cutoff values to divide the range in the total N-recommendation into classes representing N management zones.A field experiment was conducted within an annually cropped wheat field (101 ha) in northern Montana to determine whether the proposed method could improve grain yields and protein levels. The N-removal and N-deficit were estimated from site-specific wheat yield and protein data that were acquired during harvest of 1996. In 1997, which was a dry year, an experiment was conducted in the same field that consisted of a randomized complete block design arranged as pairs of strip plots. Variable- or uniform-rate N treatments were randomly assigned to each pair of strips. Both treatments received nearly the same amount of fertilizer, however, N in the variable treatment was varied to match patterns in grain yield and protein levels that previously existed in 1996. Yields were not significantly different between management systems, but proteins were significantly enhanced by spatially variable N application. In addition, variability in protein levels was reduced within the whole field. Field areas deficient in N fertility could be identified without having to sample for soil profile N. 相似文献
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试验选用黑龙江省生产实践中广泛种植的8个优良品种,并在不同稀植处理下施三叶肥、花期肥,通过田间试验对稀植栽培下春小麦氮素转移、蛋白质含量变化、产量及构成因素进行研究。结果表明,3种处理下旗叶和籽粒的氮素含量变化呈交叉式,变化规律基本一致,龙麦29和克丰6籽粒蛋白质含量表现为显著增加,其他品种蛋白质含量差异不大。稀植与常规处理下各品种产量变化表现不一致。 相似文献
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调环酸钙对小麦群体性状和产量的调控作用 总被引：1，自引：0，他引：1
为研究调环酸钙对小麦群体性状和产量的影响,应用不同剂量的10%调环酸钙泡腾颗粒剂在襄阳和东明等地进行田间试验。结果表明,在小麦拔节前施用调环酸钙10%泡腾颗粒剂10~100 g/667 m2,可矮化植株高度,缩短节间长度、增加茎粗,并能增加穗长,提高千粒重和产量。其中,施用10%调环酸钙泡腾颗粒剂50 g/667m2处理的产量最高,在襄阳和东明两地产量分别达476.36 kg/667 m2和570.85 kg/667 m2,比对照分别增产13.27%和11.80%。10%调环酸钙泡腾颗粒剂各用量均对小麦安全,无药害产生。 相似文献
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硅酸盐细菌在紫色土上应用效应研究 总被引：4，自引：1，他引：3
在５个硅酸盐细菌中，２个使油菜增产大于１０％，３个在０～１０％之间。在１０个菌中，４个细菌使小麦增产大于５％，６个在０～５％之间。说明硅酸盐细菌对小麦及油菜均有增产作用，不同菌株的效果不同，且对油菜的增产幅度大于小麦，因油菜是需钾敏感作物。 相似文献
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M. Diacono A. Castrignanò C. Vitti A. M. Stellacci L. Marino C. Cocozza D. De Benedetto A. Troccoli P. Rubino D. Ventrella 《Precision Agriculture》2014,15(5):479-498
Precision agriculture (PA) technologies allow us to assess field variability and support site-specific (SSP) application of inputs. The joint application of PA and organic farming practices might be synergetic. The objective of this 3-year study was to propose a multivariate statistical and geostatistical approach, to evaluate the effects of SSP nitrogen (N) fertilization on durum wheat in transition to organic farming. Soil parameters were measured to assess soil fertility level before the SSP fertilization on wheat, which was carried out by management zones in the third year. Radiometric measurements were performed with a hyperspectral spectroradiometer and N-uptake at anthesis and grain yield were determined. The expected values and 95 % confidence intervals of the soil parameters, N-uptake and yield data were estimated with polygon kriging for each management zone. Reflectance data were reduced through principal component analysis and the retained principal components were submitted to factorial co-kriging analysis to estimate orthogonal scale-dependent factors. Comparisons between N-uptake and yield and between the retained regionalized factors (F1) and yield were performed. The spatial pattern of F1 at shorter scales was mostly reproduced in the N-uptake map, suggesting the predictive capacity of hyperspectral data for crop N-status. Within-cluster variance for yield was reduced, quite probably as a combined effect of meteorological pattern and management. The preliminary results seem to be promising in the perspective of PA. Moreover, an inverse relationship between grain yield and crop N-status was observed. 相似文献
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冬小麦氮素吸收及产量对喷灌施肥均匀性的响应 总被引：9，自引：1，他引：9
为了为喷灌均匀系数设计标准的制订提供更充分的依据，分别于2002~2003和2003~2004年度在北京进行了喷灌施肥均匀系数和施肥量对冬小麦氮素吸收量和产量影响的田间试验。试验中生育期平均喷灌均匀系数变化范围为72%~84%。除了基肥外，其它肥料利用喷灌系统施入，生育期平均喷灌施肥均匀系数变化范围为71%~85%，喷灌施肥量的变化范围为0~180kgN/hm2。试验结果指出，在所研究的均匀系数范围内，均匀系数对氮素吸收量和产量的影响不明显。施肥量对冬小麦产量的影响不明显，但秸秆全氮含量和氮素吸收量均随施肥量的增加呈现出增加趋势。本研究结果表明，对华北平原的冬小麦喷灌来说，目前我国采用的喷灌均匀系数不小于75%的设计标准不会对氮素吸收量和产量造成负面影响。 相似文献
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Gerhards R. Sökefeld M. Timmermann C. Kühbauch W. Williams M. M. 《Precision Agriculture》2002,3(1):25-35
A four-year study of site-specific weed control is presented in this paper. Weed seedling distribution was sampled and mapped prior to and after post-emergence herbicide application in four fields planted with maize, sugar beets, winter wheat and winter barley, rotating on one site. Herbicides and other weed control strategies were applied site-specifically according to the spatial variation of weed populations. Different decision algorithms were used for chemical weed control methods in each crop. A weed treatment map was created to direct location and dosage of herbicide application. The sprayer was coupled with a differential Global Positioning System (DGPS). The solenoid valves of the sprayer were opened automatically when the tractor entered a weed patch characterized in the weed treatment map. For site specific herbicide application, a patch sprayer was developed that allowed variable rate application and the selective control of each section of the spray boom. 相似文献
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在沧州地区主推小麦品种沧麦028上,将撒可富小麦专用肥（15-20-10）在小麦播种前作底肥一次性施入,进行了不同施肥量〔0（CK）、375、600和825 kg/hm2〕对小麦产量以及麦田群体结构影响的肥效试验,以明确沧州地区撒可富小麦专用肥的适宜施肥量。结果表明：在试验施肥量范围内,施用撒可富肥能够改善小麦的产量性状,提高产量。从小麦产量、施肥效益和肥料投入3个方面综合考虑,认为在沧州市小麦生产上撒可富小麦专用肥适宜的施用量为600 kg/hm2。 相似文献
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基于多年产量数据的精准农业管理分区提取与尺度效应评价 总被引：10，自引：3，他引：10
本研究利用带有差分全球定位系统（DGPS）接收机和产量监测传感器的联合收割机获取的4年产量数据进行精准农业管理分区的提取研究。对经过一系列处理后的4年的产量数据进行栅格平均运算，得到分辨率为4 m的综合产量图。分别采用尺度为12、20、28、36、44、52、60 m 的正方形窗口对分类后的综合产量图进行众数过滤，并从方差减少率、差异显著性、空间破碎化、空间一致性4个角度进行了尺度效应评价。结果表明，分类后众数过滤法有效地去除了由随机变异造成的孤立像元或碎片，保留了实际的产量变异，增加了管理分区的有效面积，提高了管理分区的连续性。分区结果可以直接作为精准农业目标产量分区图，用于作物种植前或产中适时肥料推荐管理决策。 相似文献
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小麦玉米间作和氮肥对作物耗水特性及水分利用的影响 总被引：1，自引：0，他引：1
通过大田试验,在半湿润区雨养条件下研究小麦玉米间作种植与单作种植在两个氮肥水平下的阶段耗水量、土面蒸发特征及水分利用效率,探究间作系统中各组成作物的耗水特性以及氮肥对水分利用的调节作用。研究结果表明,间作种植模式可增加小麦耗水量、全生育期土面蒸发量与土面蒸发量占耗水量的比例(E/ET),而降低玉米耗水量。在同一种植模式下,施氮处理增加作物耗水量,同时降低全生育期土面蒸发量与土面蒸发量占耗水量的比例,说明施氮能适当地增加土壤水分的有效性。与单作相比,间作使小麦在施氮时产量、水分利用效率分别提高33.20%与12.15%,在不施氮时较单作小麦产量、水分利用效率分别提高26.97%与23.81%;玉米间作与单作种植对产量的差异不显著,但显著提高水分利用效率,在施氮时和不施氮情况下分别提高8.37%和10.06%。在同一种植模式下,施氮处理同时增加小麦和玉米的产量与水分利用效率。因此,可在半湿润区适当发展施氮处理的间作种植模式,以提高作物的水分利用效率和达到作物高产。 相似文献
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【目的】研究一体化匀播栽培技术对新疆南疆冬小麦生长发育及产量的影响。【方法】在大田条件下,设置一体化匀播和常规条播2种不同的播种方式,研究不同播种方式下冬小麦叶片叶绿素含量(SPAD值)、叶面积指数(LAI)、干物质积累及产量和产量构成因素的变化规律。【结果】与条播相比,匀播处理有利于叶绿素含量(SPAD值)的提高,增大了叶面积指数(LAI),促进干物质的积累,有效提高了籽粒产量。与常规条播相比,匀播处理节省整地、撒肥及播种作业费1 320元/hm2,节约肥料投入成本421.5元/hm2;2年籽粒产出效益分别增加了5.93%(2017年)和22.75%(2018年)。【结论】冬小麦一体化匀播具有高产、节本增效、肥料利用率高的优点。 相似文献
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1978—1979年,我们进行“春小麦丰产规律”的研究,在河西平川灌区的张掖、武威和冷凉灌区的黄羊镇,种植四因素三水平正交试验和大田丰产栽培试验,亩产量在800—1000斤之间。通过试验和调查,从土壤肥力、品种生态类型、种子的发芽出苗、产量结构、分蘖成穗、光合生产率、矿物质营养、土壤水分供应八个方面,总结出春小麦高产的生理生态指标,为大田生产提供技术指标规范和组合。 相似文献
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Delineation and Scale Effect of Precision Agriculture Management Zones Using Yield Monitor Data Over Four Years 总被引：1，自引：0，他引：1
LI Xiang PAN Yu-chun GE Zhong-qiang ZHAO Chun-jiang 《中国农业科学(英文版)》2007,6(2):180-188
In this study, precision agriculture management zones were delineated using yield data over four years from the combine harvester equipped with yield monitor and DGPS receiver. Relative yields measured during each year were interpolated to 4 m2 grid size using ordinary kriging. The resultant interpolated yield maps were averaged across years to create a map of the mean relative yield, which was then used for cluster analysis. The mean yield map of post-classification was processed by applying majority filtering with window sizes that were equivalent to the grid sizes of 12, 20, 28, 36, 44, 52 and 60 m. The scale effect of management zones was evaluated using relative variance reduction, test of significant differences of the means of yield zones, spatial fragmentation, and spatial agreement. The results showed that the post-classification majority filtering （PCMF） eliminated lots of isolated cells or patches caused by random variation while preserving yield means, high variance reduction, general yield patterns, and high spatial agreement. The zoned result can be used as yield goal map for preplant or in-season fertilizer recommendation in precision agriculture. 相似文献
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Ramped calibration strips have been suggested as a way for grain producers to determine nitrogen needs more accurately. The
strips use incrementally increasing levels of nitrogen and enable producers to conduct an experiment in each field to determine
nitrogen needs. This study determines whether predictions from the program Ramp Analyzer 1.2 are replicable in Oklahoma hard
red winter wheat (Triticum aestivum). Predictions are derived from 36 individual strips from on-farm experiments—two pairs of adjacent strips at each of nine
winter wheat fields in Canadian County, OK. The two pairs of strips within each field were between 120 and 155 m apart. Each
strip was analyzed three times during the 2006–2007 growing season. Nitrogen recommendations from Ramp Analyzer 1.2 are not
correlated even for strips that were placed side by side, and recommendations from strips in the same field show no more homogeneity
than randomly selected strips throughout the county. The results indicate that ramped calibration strips are unlikely to produce
accurate nitrogen requirement predictions at any spatial scale, whether at the county level or for subsections of a single
field. In contrast, a procedure that uses only measures from the plot with no nitrogen and the plot with the highest level
of nitrogen applied does show replicability. Thus, improvements in the ramped calibration strip technology are needed if it
is to become viable. 相似文献