MED-Mediterranean Institute for Agriculture, Environment and Development and CHANGE-Global Change and Sustainability Institute, Universidade de Évora, Pólo da Mitra, Ap. 94, 7006-554 Évora, Portugal.
AgroInsider Lda., 7005-841 Évora, Portugal.
Sensors (Basel). 2023 Jan 12;23(2):888. doi: 10.3390/s23020888.
The economic and environmental sustainability of extensive livestock production systems requires the optimisation of soil management, pasture production and animal grazing. Soil compaction is generally viewed as an indicator of soil degradation processes and a determinant factor in crop productivity. In the Montado silvopastoral ecosystem, characteristic of the Iberian Peninsula, animal trampling is mentioned as a variable to consider in soil compaction. This study aims: (i) to assess the spatial variation in the compaction profile of the 0-0.30 m deep soil layer over several years; (ii) to evaluate the effect of animal trampling on soil compaction; and (iii) to demonstrate the utility of combining various technological tools for sensing and mapping indicators of soil characteristics (Cone Index, CI; and apparent electrical conductivity, EC), of pastures' vegetative vigour (Normalised Difference Vegetation Index, NDVI) and of cows' grazing zones (Global Positioning Systems, GPS collars). The significant correlation between CI, soil moisture content (SMC) and EC and between EC and soil clay content shows the potential of using these expedient tools provided by the development of Precision Agriculture. The compaction resulting from animal trampling was significant outside the tree canopy (OTC) in the four evaluated dates and in the three soil layers considered (0-0.10 m; 0.10-0.20 m; 0.20-0.30 m). However, under the tree canopy (UTC), the effect of animal trampling was significant only in the 0-0.10 m soil layer and in three of the four dates, with a tendency for a greater CI at greater depths (0.10-0.30 m), in zones with a lower animal presence. These results suggest that this could be a dynamic process, with recovery cycles in the face of grazing management, seasonal fluctuations in soil moisture or spatial variation in specific soil characteristics (namely clay contents). The NDVI shows potential for monitoring the effect of livestock trampling during the peak spring production phase, with greater vigour in areas with less animal trampling. These results provide good perspectives for future studies that allow the calibration and validation of these tools to support the decision-making process of the agricultural manager.
广泛的畜牧生产系统的经济和环境可持续性要求优化土壤管理、牧草生产和动物放牧。土壤压实通常被视为土壤退化过程的指标，也是作物生产力的决定因素。在伊比利亚半岛特有的蒙塔多农牧生态系统中，动物踩踏被认为是土壤压实的一个变量。本研究旨在：（i）评估多年来 0-0.30 米深土壤层压实剖面的空间变化；（ii）评估动物踩踏对土壤压实的影响；（iii）展示结合各种技术工具来感知和绘制土壤特性（锥指数，CI；和表观电导率，EC）、牧草植被活力（归一化差异植被指数，NDVI）和奶牛放牧区（全球定位系统，GPS 项圈）指标的效用。CI、土壤水分含量（SMC）和 EC 之间以及 EC 和土壤粘粒含量之间的显著相关性表明，使用这些由精准农业发展提供的便捷工具具有潜力。在四个评估日期和三个考虑的土壤层（0-0.10 m；0.10-0.20 m；0.20-0.30 m）中，动物踩踏产生的压实作用在树冠外（OTC）非常显著。然而，在树冠下（UTC），动物踩踏的影响仅在 0-0.10 m 土壤层和四个日期中的三个中显著，在动物存在较少的区域，CI 深度更大（0.10-0.30 m）。这些结果表明，这可能是一个动态过程，在放牧管理、土壤水分季节性波动或特定土壤特性（即粘粒含量）的空间变化下，具有恢复周期。NDVI 具有监测春季生产高峰期牲畜踩踏影响的潜力，在动物踩踏较少的区域，活力更强。这些结果为未来的研究提供了很好的前景，这些研究允许对这些工具进行校准和验证，以支持农业管理者的决策过程。
