Evaluation of Soil Management Effect on Crop Productivity and Vegetation Indices Accuracy in Mediterranean Cereal-Based Cropping Systems.

Roberto Orsini,Marco Fiorentini,Stefano Zenobi

doi:10.3390/s20123383

Abstract

Mostly, precision agriculture applications include the acquisition and elaboration of images, and it is fundamental to understand how farmers’ practices, such as soil management, affect those images and relate to the vegetation index. We investigated how long-term conservation agriculture practices, in comparison with conventional practices, can affect the yield components and the accuracy of five vegetation indexes. The experimental site is a part of a long-term experiment established in 1994 and is still ongoing that consists of a rainfed 2-year rotation with durum wheat and maize, where two unfertilized soil managements were repeated in the same plots every year. This study shows the superiority of no tillage over conventional tillage for both nutritional and productive aspects on durum wheat. The soil management affects the vegetation indexes’ accuracy, which is related to the nitrogen nutrition status. No-tillage management, which is characterized by a higher content of soil organic matter and nitrogen availability into the soil, allows obtaining a higher accuracy than the conventional tillage. So, the users of multispectral cameras for precision agriculture applications must take into account the soil management, organic matter, and nitrogen content.

Highlights

Providing a sufficient amount of food to satisfy the nutritional demand of the current population is the essential goal of global agriculture
All these consequences are much more accentuated in the conventional tillage (CT) because it has a greater porosity of the soil than no tillage (NT) where there is an increased number of soil micropores that facilitate the storage of soil moisture [81,82,83], a lower soil organic matter than NT (Table 2) that plays a key role in water [84,85,86] and nutrient [87,88,89] retention thanks to the mulching effect of the straw [88], as well as having no crop residues on the topsoil during the season due to the soil tillage, which involves a re-mixing of the horizons and a dilution of the crop residues [90,91,92]
By evaluating the performance of the vegetation indices (VIs) to be related with the crop N content (g m−2), we suggest the use of Normalized Difference Red Edge Index (NDRE) and MSAVI2 to provide to farmers the vegetation index maps and the prescriptions maps for precision agriculture application

Summary

Introduction

Providing a sufficient amount of food to satisfy the nutritional demand of the current population is the essential goal of global agriculture. Conventional tillage (CT) techniques have allowed the adoption of crops, especially on large surfaces ensuring high yields: the mixing of surface horizons in preparing the seedbed allows the stabilization of the main crop to the detriment of the weed competitors This intensification of the crops, necessary for responding to the food needs of the growing demographic pressure, is proving unsustainable: the increment of soil erosion [3,4], the use of water, energy, and fertilizers, the disruption of soil structure, and the reduction of water use efficiency [5] will probably increase the environmental and economic pressures posed by intensified agricultural activities [6]; the negative consequences for the environment are evident [7,8,9].

Methods

Discussion

Conclusion