Research Group in AgroICT and Precision Agriculture, Agrotecnio Center, University of Lleida, Av. Rovira Roure 191, 25198 Lleida, Catalonia, Spain.
Università degli Studi di Padova, Department of Land, Environment, Agriculture and Forestry, Padova, Veneto, Italy.
Sci Total Environ. 2018 Sep 1;635:343-352. doi: 10.1016/j.scitotenv.2018.04.153. Epub 2018 Apr 16.
The change from traditional to a more mechanized and technical agriculture has involved, in many cases, land transformations. This has supposed alteration of landforms and soils, with significant consequences. The effects of induced soil variability and the subsequent implications in site-specific crop management have not been sufficiently studied. The present work investigated the application of a resistivity soil sensor (Veris 3100), to map the apparent electrical conductivity (ECa), and detailed multispectral airborne images to analyse soil and crop spatial variability to assist in site-specific orchard management. The study was carried out in a peach orchard (Prunus persica (L.) Stokes), in an area transformed in the 1980 decade to change from rainfed arable crops to irrigated orchards. A total of 40 soil samples at two depths (0-30cm and 30-60cm) were analysed and compared to ECa and the normalised difference vegetation index (NDVI). Two types of statistical analysis were performed between ECa or NDVI classes with soil properties: a linear correlation analysis and multivariate analysis of variance (MANOVA). The results showed that the land transformation altered the spatial distribution and continuity of soil properties. Although a relationship between ECa and peach tree vigour could be expected, it was not found, even in the case of trees planted in soils with salts content above the tolerance threshold. Two types of management zones were proposed: a) zones delineated according to ECa classes to leach salts in the high ECa zones, and b) zones delineated according to NDVI classes to regulate tree vigour and yield. These strategies respond to the alteration of the original soil functions due to the land transformation carried out in previous years.
从传统农业向更加机械化和技术化农业的转变，在许多情况下都涉及到土地的改造。这意味着地貌和土壤的改变，带来了重大的影响。土壤可变性的影响以及随后对特定地点作物管理的影响尚未得到充分研究。本研究应用电阻土壤传感器（Veris 3100）来绘制土壤表观电导率（ECa），并结合详细的多光谱航空图像来分析土壤和作物的空间变异性，以协助特定地点的果园管理。研究在一个桃果园（Prunus persica (L.) Stokes）中进行，该果园在 20 世纪 80 年代进行了改造，从雨养耕地转变为灌溉果园。共分析了 40 个土壤样本，深度为 0-30cm 和 30-60cm，并与 ECa 和归一化差异植被指数（NDVI）进行了比较。在 ECa 或 NDVI 类与土壤特性之间进行了两种类型的统计分析：线性相关分析和多元方差分析（MANOVA）。结果表明，土地改造改变了土壤特性的空间分布和连续性。尽管可以预期 ECa 与桃树活力之间存在关系，但即使在种植在盐分含量超过耐受阈值的土壤中的树木中也没有发现这种关系。提出了两种管理区类型：a）根据 ECa 类划分的区域，用于淋洗高 ECa 区的盐分，b）根据 NDVI 类划分的区域，用于调节树木活力和产量。这些策略是对前几年进行的土地改造导致的原始土壤功能改变的回应。
