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1.
基于物联网和LSTM的柑橘园土壤含水量和电导率预测模型 总被引：2，自引：1，他引：1
目的 构建柑橘果园环境信息物联网实时采集系统，建立基于物联网和长短期记忆(LSTM)的柑橘园土壤含量和电导率预测模型，为果园灌溉施肥管理、效果预测评估提供参考依据。方法 利用土壤温度、含水量、电导率三合一传感器，在柑橘果园中设置5个节点和1个气象站，通过ZigBee短距离无线通信和GPRS远距离无线传输，将果园气象数据和土壤墒情数据传输至远程服务器。利用LSTM模型建立气象数据与土壤含水量和电导率的预测模型，计算均方根误差(RMSE)和决定系数(R2)以进行性能评估。结果 物联网系统能够实现远程传输柑橘果园环境数据，建立了基于LSTM和广义回归神经网络(GRNN)的土壤含水量和电导率预测模型，模型在5个节点的数据集的训练结果分别为：LSTM模型训练的土壤含水量和电导率的RMSE范围分别为6.74~8.65和6.68~8.50，GRNN模型训练的土壤含水量和电导率的RMSE范围分别为7.01~14.70和7.60~13.70。利用生成的LSTM模型和气象数据进行拟合，将土壤含水量和电导率的预测值与实测值进行回归分析，LSTM模型拟合的土壤含水量和电导率的R2范围分别为0.760~0.906和0.648~0.850，GRNN模型拟合的土壤含水量和电导率的R2范围分别为0.126~0.369和0.132~0.268，说明LSTM模型的性能表现较好。结论 建立了柑橘果园环境的物联网信息传输系统，构建的基于LSTM的果园土壤含水量和电导率预测模型具有较高的精度，可用于指导柑橘果园的灌溉施肥管理。 相似文献
2.
鄂东南红壤水分特性的研究 总被引：2，自引：1，他引：2
研究了鄂东南地区５种母质发育的红壤水分特性。结果表明，红壤的持水性以四纪红色粘土，泥质页岩和砂质页岩发育的红壤持水性较强，石英砂岩，花岗岩发育的红壤持水性较弱。土壤水分的有效性以表土层的土壤水效性较高，土壤的导水性和土壤的爱气孔隙有关。 相似文献
3.
内蒙古解放闸灌域表层土壤多氯联苯污染特征和来源分析 总被引：2，自引：1，他引：1
在内蒙古解放闸灌域采集49个表层土壤样品,采用气相色谱-电子捕获检测器(GC-ECD)测定8种多氯联苯PCBs的浓度,探讨PCBs的污染特征、组成特征、空间分布和污染来源,以及土壤理化性质对PCBs浓度分布的影响。结果表明,解放闸灌域表层土壤中∑PCBs浓度范围为ND～209.95 ng·g~(-1),均值为15.09 ng·g~(-1),与国内外其他地区相比,处于较低污染水平。PCB1、PCB29和PCB47的均值和检出率均较高,是解放闸灌域表层土壤中的优势污染物。土壤中PCBs同系物组成表现为:PCB29(38.65%)PCB1(33.33%)PCB47(11.62%)PCB5(8.25%)PCB98(8.14%),其余单体的检出量很少,说明主要以低氯联苯污染为主。土壤中PCBs浓度的空间分布存在一定差异性,表现为东北高于西南,其西南部呈点状分布。土壤理化性质对PCBs浓度的影响表现为:PCBs浓度分布受pH值的影响,而不受有机质、EC值、砂粒、粉粒和黏粒的影响。相关性分析和因子分析结果显示,解放闸灌域表层土壤中PCBs的污染源主要来自电容器和变压器油的泄露。 相似文献
4.
5.
The adoption of precision viticulture requires a detailed knowledge of variation in soil chemical, physical and profile properties.
This study evaluates the usefulness of apparent electrical conductivity (ECa) data within a GIS framework to identify variations in soil chemical and physical properties and moisture content. The work
was conducted in a vineyard located in the Carneros Region (Napa Valley, California). The soil was sampled using 44 boreholes
to quantify chemical and physical characteristics and 9 open pits to verify the borehole observations. Moisture content was
determined using time domain reflectometry (TDR). To characterize soil ECa, three campaigns were undertaken using a soil electrical conductivity meter (EM38). Linear regressions between soil ECa and soil properties were determined. Boreholes and TDR data were interpolated by kriging to characterize the spatial distribution
of soil variables. The resulting maps were compared to the results obtained using the best ECa linear regressions. Using ECa measurements, soil properties like extractable Na+ and Mg2+, clay and sand content were well estimated, while best estimates were obtained for extractable Na+ (r
2
= 0.770) and clay content (r
2
= 0.621). The best estimates for soil moisture content corresponded to moisture in the deeper soil horizons (r
2
= 0.449). The methods described above provided maps of soil properties estimated by ECa in a GIS framework, and could save time and resources during vineyard establishment and management. 相似文献
6.
采用时空替代法,选取岷江上游大沟流域内不同恢复时期(12、18、25、35a)的人工油松林为研究对象,研究了植被恢复过程中土壤理化性质及有机碳含量的变化特征,同时探讨了它们之间的相互关系.研究结果表明沿恢复梯度,土壤质量得到了改善,主要表现为土壤粘粒含量、比表面积、有机质含量显著增加,土壤粉粒含量和pH值则显著下降.土壤有机质与土壤粘粒和比表面积呈显著正相关,与土壤容重呈显著负相关.此外,土壤有机碳含量沿恢复梯度显著增加,0-50 cm内土壤有机碳含量从5.59 kg/m2增加到12.64 kg/m2,土壤年平均固碳速率为0.31 kg/m2. 相似文献
7.
民勤不同林龄胡杨根区土壤理化性质及相关性分析 总被引：1，自引：0，他引：1
以民勤不同林龄胡杨根区土壤为对象，采集0~200 cm土壤样品，并对土壤的物理性质、养分含量及其相关性进行了分析。结果表明:1）随着胡杨林龄增加，土壤含水量增加，土壤中黏粒含量逐渐增加，粗砂粒含量减少，粉粒、细砂粒差异不明显。2）土壤有机质、全N、电导率变化均表现为成熟林＞中龄林＞幼龄林，且表层（0~20 cm）含量显著高于其他土层，表聚性明显。3个林龄胡杨根区土壤速效P含量、pH差异不显著（P＞0.05）。3）土壤理化性质之间关系密切，土壤含水量与黏粒、粉粒、有机质、全N、速效P、电导率均呈极显著（P<0.01）正相关，与粗砂粒呈极显著（P<0.01）负相关。黏粒、粉粒含量与含水量、有机质、全N、速效P均呈极显著（P<0.01）正相关。研究结果表明，林龄的增加改善了胡杨根区土壤理化性质，为干旱区胡杨的抚育与发展提供理论依据。 相似文献
8.
The creation of fine resolution soil maps is hampered by the increasing costs associated with conventional laboratory analyses of soil. In this study, near infrared (NIR) reflectance spectroscopy was used to reduce the number of conventional soil analyses required by the use of calibration models at the farm scale. Soil electrical conductivity and mid infrared reflection (MIR) from a satellite image were used and compared as ancillary data to guide the targeting of soil sampling. About 150 targeted samples were taken over a 97 hectare farm (approximately 1.5 samples per hectare) for each type of ancillary data. A sub-set of 25 samples was selected from each of the targeted data sets (150 points) to measure clay and soil organic matter (SOM) contents for calibration with NIR. For the remaining 125 samples only their NIR-spectra needed to be determined. The NIR calibration models for both SOM and clay contents resulted in predictions with small errors. Maps derived from the calibrated data were compared with a map based on 0.5 samples per hectare representing a conventional farm-scale soil map. The maps derived from the NIR-calibrated data are promising, and the potential for developing a cost-effective strategy to map soil from NIR-calibrated data at the farm-scale is considerable. 相似文献
9.
比较了三种土壤类型(黄筋泥、红泥土和红砂土)、四类利用方式(林地、果园、茶园和旱地)及二个土层(0～15 cm和15～30 cm)之间主要肥力质量指标量值的变化.结果表明,大部分土壤质量指标的量值与土壤类型、利用方式和土层深度有密切的关系.其中,粘粒含量、>0.25 mm和>5 mm的风干团聚体、>0.25 mm水稳定性团聚体含量及CEC与土壤类型关系密切;全磷、有效磷、有效钾、交换性酸和pH值主要与利用方式有关;容重、饱和导水率、有机碳、全氮、有效氮和根系数量与土壤类型和利用方式均存在密切关系.表土层与亚表层之间的粘粒含量、容重、饱和导水率、有机碳、全氮、全磷、有效磷、有效钾、有效氮及pH都存在显著的差异. 相似文献
10.
为解决遥感技术在监测耕层土壤有机质方面的应用问题,利用表层土壤光谱对耕层土壤有机质含量进行估测。以山东省济南市章丘区的表层、耕层各76个土壤样本为研究对象,首先对表层光谱数据进行小波变换去噪、剔除异常样本等处理,然后对处理后的光谱反射率进行一阶微分等10种数学变换,在对数倒数一阶微分和对数一阶微分变换后的反射率数据中选取43个与土壤有机质含量相关系数较高的波段,通过主成分分析以累计贡献率大于90%的标准选取5个主成分作为反演因子,利用BP神经网络(BPNN)、支持向量机回归(SVR)和多元线性回归(MLR)方法建立耕层土壤有机质含量间接估测模型。结果表明,耕层土壤与表层土壤有机质含量之间决定系数R~2达到0.839,显著性P0.01,存在着较强的相关性BPN估测模型的精度最优,决定系数R~2为0.845,平均相对误差为7.642%,RMSE分别为1.622g·kg~(-1)。研究表明,利用表层土壤光谱信息间接估测耕层有机质含量是可行有效的,为耕层土壤有机质的估测问题提供了一种新思路。 相似文献
11.
湘东丘陵4种林地深层土壤颗粒有机碳及其组分的分配特征 总被引：1，自引：0，他引：1
选取湘东丘陵区4种典型母质发育的林地土壤(花岗岩红壤、板岩红壤、第四纪红土红壤、酸性紫色土),分层次采集土壤剖面样品,采用物理分组方法,研究深层土壤颗粒有机碳(POC)及其组分(粗颗粒有机碳CPOC、细颗粒有机碳FPOC)的数量分布和分配比例,探讨POC及其组分与土壤有机碳、质地的关系。结果表明,4种土壤剖面POC储量介于2.63-11.59 t/hm2,以花岗岩红壤最高,其次为板岩红壤,第四纪红土红壤和酸性紫色土相对最低。4种土壤POC占SOC的比例(POC/SOC)介于1.5%-13.9%,花岗岩红壤POC/SOC随剖面加深而升高,板岩红壤和第四纪红土红壤则降低,紫色土POC/SOC在40-60 cm土层达到最大值后迅速降低。在40 cm以下的深层土壤中,花岗岩红壤和紫色土保存有数量可观、比例更高的POC。第四纪红土红壤POC储量相对较少、POC/SOC也在表土层较高。花岗岩红壤POC中以CPOC为主,而紫色土以FPOC为主,板岩红壤和第四纪红土红壤中CPOC和FPOC比例接近。所选4种土壤POC组分中,FPOC数量更能代表SOC数量的变化。SOC储量和质地是影响不同母质土壤POC及其组分分配差异的重要因素,在林地开发利用中也应重视深层土壤(40 cm)中储藏的活性碳组分。 相似文献
12.
黏土对沙地土壤改良效果的微形态研究——以内蒙古科尔沁沙地为例 总被引：1，自引：1，他引：0
为了研究施加黏土后的沙地土壤微形态特征,说明其改良效果,对内蒙古科尔沁沙地土壤切片进行观察,并利用土壤切片图像处理分析系统和Image-Pro Plus 6.0软件进行处理和分析,提取基质、孔隙和粗骨颗粒等和土壤肥力状况相关的定量化数据进行分析及定性分析,结果表明:施加黏土后,出现了块状微结构和雏形团聚体;从基质比、毛管孔隙占比方面来说,底施处理效果更好,基质比在C2(3×10~5 kg/hm~2)处理水平比对照组提高了8.8%,毛管孔隙占比在C3(6×10~5kg/hm~2)处理水平提高了15%;就总孔隙百分比、粗骨颗粒磨圆度、粉粒百分比、粗骨颗粒平均粒径来说,表施处理效果比较好,C1(1.5×10~5 kg/hm~2)、C2(3×10~5 kg/hm~2)处理水平均有显著改善。结论:1)施加黏土后,沙地土壤结构与原始沙地的粒状微结构相比有一定的改善;2)短期底施处理下,C1和C2处理单元的基质比有所提高,毛管孔隙占比随着黏土施加量的增加而提高;粗骨颗粒特征方面,表施处理效果比底施效果要好;3)短期改良情况下,沙地土壤微结构并没有太大的变化,还是以粗骨颗粒为主,但改良后出现一些雏形团聚体,各量化指标均有不同程度的提高。 相似文献
13.
为探讨耐盐植物种植对滨海盐土化学性质及微生物群落结构的影响,在滨海盐土环境下,以种植耐盐植物费菜（Sedum aizoon L.）、田菁（Sesbania cannabina（Retz.）Poir.）、蒲公英（Taraxacum mongolicum Hand.-Mazz.）的样地和未种植植物的裸地土壤（CK）为研究对象,采用土壤农化分析技术和磷脂脂肪酸（PLFA）生物标记法,对土壤化学性质、微生物群落结构及多样性进行分析。结果表明,与裸地比较,种植植物样地土壤电导率和速效钾含量均显著下降,分别下降了20.26%~57.21%和23.42%~37.80%;而有机质含量和有效磷含量显著升高,分别升高了39.16%~53.01%和106.48%~259.92%。种植植物样地土壤中PLFA种类明显增加,微生物群落也有所改变,3个植物样地土壤中总PFLAs含量和革兰氏阴性菌、放线菌、AM真菌、真核生物、真菌PFLA含量显著升高,分别升高21.53%~103.32%、4.96%~63.37%、82.91%~222.72%、50.00%~160.25%、32.05%~268.59%、19.39%~454.77%;真菌/细菌（F/B）PFLA含量也显著升高1.00~6.50倍,而革兰氏阳性菌PFLA含量和革兰氏阳性菌/革兰氏阴性菌（G+/G-）PFLA含量却显著下降,分别下降了48.06%~57.78%和59.77%~68.68%。此外,种植植物样地土壤微生物群落结构多样性也明显提高。研究表明,种植费菜和蒲公英可以降低滨海盐土土壤电导率,有利于土壤有机质的积累,同时其促进多种微生物的繁殖,可有效改善滨海盐土的微生态环境。 相似文献
14.
【目的】建立基于可见-近红外光谱的土壤游离铁精确预测模型,简单、快速、经济地预测土壤游离铁,有助于研究土壤发生和分类。【方法】采集广西壮族自治区的铁铝土、富铁土、淋溶土和雏形土等82个旱地土壤剖面的B层土壤,进行室内土壤化学分析、光谱测定,分析不同光谱变换后的光谱反射率与土壤游离铁含量的相关性。基于特征波段利用偏最小二乘回归(PLSR)和逐步多元线性回归(SMLR)法建立土壤游离铁含量光谱预测模型,通过决定系数(R2)、均方根误差(RMSE)和相对预测偏差(PRD)确定最优模型。【结果】土壤光谱曲线分别在457、800和900 nm波段附近有明显的游离铁吸收和反射峰特征;土壤游离铁含量与原始光谱反射率呈负相关;原始光谱经过微分变换后,游离铁含量与光谱反射率相关性显著提高;基于400～580和760～1 300 nm特征波段和一阶微分光谱变换的SMLR模型预测精度最高,其验证集的R2和RPD分别为0.85和2.62,RMSE为8.41 g·kg~(-1)。【结论】将可见近红外光谱技术应用于土壤游离铁含量高效快速地预测具有良好的可行性。广西旱地土壤光谱反射率与土壤游离铁含量具有高度的相关性,应用逐步多元线性回归方法可以很好地建立土壤游离铁含量反演模型。 相似文献
15.
El-Naggar A. G. Hedley C. B. Roudier P. Horne D. Clothier B. E. 《Precision Agriculture》2021,22(4):1045-1066
Soil water content (θ) measurement is vital for accurate irrigation scheduling. Electromagnetic induction surveys can be used to map spatial variability of θ when other soil properties are uniform. However, depth-specific θ variations, essential for precision irrigation management, have been less investigated using this method. A quasi-2-dimensional inversion model, capable of inverting apparent soil electrical conductivity (ECa) data to calculate estimates of true electrical conductivity (σ) down the entire soil profile, was developed using ECa data collected by a multi-coil Dualem-421S sensor. The optimal relationships between σ and volumetric water content (θv) were established using all coil arrays of the Dualem-421S, a damping factor of 0.04, an initial model of 35 mSm?1, and with ten iterations (R2?=?0.70, bias?=?0.00 cm3cm?3, RMSE?=?0.04 cm3cm?3). These relationships were then used to derive soil profile images of these properties, and as expected, θv and σ follow similar trends down the soil profile. The derived soil profile images for θv have potential use for irrigation scheduling to two ECa-derived soil management zones under a variable rate irrigation system at this case study site. They reflect the intrinsic soil differences that occur between texture, texture transitions and drainage characteristics. The method can also be used to guide placement of soil moisture sensors for in-season monitoring of spatio-temporal variations of θv. This soil imaging method showed good potential for predicting 2D depth profiles of soil texture, moisture and drainage characteristics, and supporting soil, plant and irrigation management.
相似文献16.
湘南红壤区三种土壤水热状况的研究 总被引：1，自引：2，他引：1
对同一地形和同一气候条件下湘南三种典型红壤的水热状况及它们的持水和渗透性质进行了研究。这三种土壤是：花岗岩母质发育的红壤、第四纪红土发育的红壤和紫色土。试验结果表明：第四纪红土发育的红壤持水性好，团聚度高，整个土体水分含量高，然而水分有效性低，渗透性好；花岗岩母质红壤则相反；紫色土则由于含有较多的块状物，因此渗透性也比较好。三种土壤的热量状况有很大的区别，紫色土在整个测定期间始终保持着较高的温度，而且温度的变幅大，花岗岩母质红壤的土体温度是三种土壤中最低的。植被影响土壤的水热状况，而水热状况又反过来影响作物的生长。 相似文献
17.
不同母质发育红壤上玉米生长与土壤pH、交换性铝、交换性钙的关系 总被引：4，自引：1，他引：3
为探明红壤酸害的机理,采集了三种母质发育的红壤,经酸度调控后进行玉米盆栽试验。研究结果表明,玉米生物量与土壤pH的关系:土壤pH临界点为5.5左右,母质不同,临界点略有差异。土壤pH小于pH临界点时,玉米生物量随土壤pH的增加而线性增加,大于pH临界点时,玉米生物量基本保持不变(第四纪红土)或略有下降(板页岩、红砂岩)。土壤pH与交换性铝含量的关系:当土壤pH小于pH临界点时,随着土壤pH的增加,交换性铝含量直线下降;当土壤pH大于pH临界点时,交换性铝含量接近0,基本保持不变。土壤pH与交换性钙含量关系:第四纪红土土壤交换性钙含量随土壤pH增加线性增加;当土壤pH大于pH临界点时,板页岩、红砂岩土壤交换性钙含量随土壤pH呈线性增加,当土壤pH小于pH临界点时,土壤交换性钙含量基本保持不变,其值很小。不同母质发育的红壤,其土壤pH及交换性铝、交换性钙含量的临界值分别为第四纪红土:5.48及0.14、4.59 cmol·kg~(-1);板页岩:5.82及0.16、5.46 cmol·kg~(-1);红砂岩:5.54及0.13、3.06 cmol·kg~(-1)。 相似文献
18.
Germination conditions are determined by hydraulic, thermal and mechanical properties of the soils. In heterogeneous fields,
the most favourable seeding depth varies spatially. To investigate the influence of seeding depth on emergence and grain yield
of corn, corn was planted in depths of 40, 50, 60, 70, 80 and 90 mm in three experimental years (2006–2008). The apparent
soil electrical conductivity was measured with an EM38. The apparent electrical conductivity was used as a proxy for soil
texture, top-soil thickness, effective root zone thickness, soil water content and soil structure. The spatial dependencies
among emergence, yield and apparent electrical conductivity were considered by including spatial models into the statistical
analysis. The results showed significant correlations of the apparent soil electrical conductivity, of the experimental year,
and of the seeding depth with the emergence of corn. Deeper planted corn (80 or 90 mm) resulted in more emergence than shallow
planted corn (+4.4% in 2006, +1.2% in 2007 and +1.5% in 2008). The emergence decreased with increasing apparent soil electrical
conductivity values. The corn grain yield was significantly affected by the soil electrical conductivity, by emergence and
by the experimental year. Increasing apparent soil electrical conductivity values were correlated with decreasing yield (from
7.5 to 3.4 Mg ha−1 in 2006, from 10.8 to 5.3 Mg ha−1 in 2007 and from 8.4 to 2.9 Mg ha−1 in 2008). Increasing emergence resulted in increasing yield. 相似文献
19.
为了分析黄河三角洲滨海湿地土壤电导率及盐离子组成沿水盐梯度的分布规律,沿自黄河向海的方向选择了假尾拂子茅湿地、香蒲湿地、芦苇湿地、柽柳和盐地碱蓬混生湿地和盐地碱蓬湿地作为研究样地,于2014年在各类型湿地内采集0～50 cm的土壤,并测定土壤电导率和6种盐离子。结果表明,盐地碱蓬湿地0～50 cm土壤的电导率、钠离子、钾离子和氯离子显著高于其他湿地(P0.05),镁离子、钙离子和硫酸根离子的最高值则出现在柽柳和盐地碱蓬混生湿地。在剖面方向上,电导率和6种盐离子表现出不同的变化趋势。线性相关分析表明,土壤电导率和6种盐离子呈显著正相关关系(P0.05)。土壤电导率和盐离子在2014年均表现出强变异特征。研究表明,沿自河向海的水盐梯度,湿地土壤电导率、钠离子、钾离子、镁离子、钙离子、氯离子和硫酸根离子总体呈现逐渐上升的趋势,土壤电导率的变化主要受钠离子和氯离子含量变化的影响。 相似文献
20.
Utilizing soil electrical conductivity (EC) measurements and terrain attributes for precision management will require secondary soil information for adequate interpretation. The objective of this study was to determine whether readily available second-order soil surveys were of adequate quality to aid with interpreting soil EC and terrain data. For three locations in Kentucky, USA, first-order soil surveys were created, second-order surveys reports were obtained, elevation was measured and used to calculate terrain attributes (slope, aspect, plan curvature, profile curvature), and bulk soil electrical conductivity was measured. Three analytical methods (an ordinary least squares analysis and two random field analyses), visual map assessment, and examination of least-squares means were used to assess the relationships between soil EC measurements, terrain attributes and first- and second-order soil surveys. The OLS and random field analyses were problematic. However, the ranking of the OLS F-statistics appeared to reflect the general relationship between landscape variables and first-order soil surveys. The landscape variables related particularly well with soil properties that had been impacted by past soil erosion. Unfortunately, however, second-order soil surveys in this study were not created at suitable scales to adequately interpret EC and terrain data regarding erosion history or other attributes. While these surveys may provide some useful information, field measurements, sampling, and observations will likely be required to develop high quality interpretations of soil EC and terrain attribute data. 相似文献