Spatial and temporal evolution of olive cultivation due to pest attack, using remote sensing and satellite image processing

Abstract

Climate change, as well as the appearance of pests and diseases, are affecting olive plantations (Olea europaea L.) and the production of olives in the world, therefore, there is an urgent need for tools to help us identify the spatial and temporal evolution of the olive groves, regarding the attack of pests, in this case, the Orthezia olivicola and the olive borer Phloeotribus scarabaeoides. In this work, we use information from freely available satellite images that allowed us to carry out spatial and temporal analysis and the combination of vegetation indices. For the studied area, according to the values of the NDVI (Normalized Difference Vegetation Index), it was identified that the surface of diseased plants ranges from 42% to 68%, moderately healthy plants from 2% to 18%, and the state of the plantation considered as very healthy plants with a tendency to zero, which means that practically 100% of the olive trees are affected by some level. The temporal variation of the NDVI, DVI, SAVI, GNDVI, EVI2, and MSAVI indices, allowed us to establish the states of affectation as mild, moderate pest attack, the severity of the pest attack added to the water deficit, and very strong pest attack and state of permanent wilting.

Spatio-Temporal Evolution of Olive Tree Water Status Using Land Surface Temperature and Vegetation Indices Derived from Landsat 5 and 8 Satellite Imagery in Southern Peru

“…Annual rainfall is scarce and even non-existent, characteristic of the driest desert in the world [8,[31][32][33]; the water deficit does not allow agricultural demands to be met, so groundwater is used almost entirely. Moreover, the predominant crop is the olive tree, which faces extreme stress conditions, with planting frames of 5 × 5, 7 × 7 and 10 × 10 m, mostly under drip irrigation [7].…”

“…NDVI is an important indicator of crop vigour, so it was used to determine the regions of interest (ROI) according to the vigour characteristic of the olive tree. Research by [7] identified olive crop vigour ranges for arid areas as 0.1 to 0.21 (withered), 0.21 to 0.25 (severe), 0.25 to 0.37 (moderate), 0.37 to 0.42 (light) and 0.42 to 1.0 (healthy).…”

“…NDVI is an excellent indicator of vigour and water stress in the crop. Its vigour classification was carried out in a previous study by [7], in plantations from 3 to 60 years old, using different VIs (NDVI, DVI, SAVI, GNDVI, EVI2 and MSAVI), obtained through spectral ranges that classify vigour as wilted, severe, moderate, mild and healthy. This study was considered highly relevant because it was conducted in an area within our study area.…”

“…The range of the study months represents the summer season, the months with the highest temperatures during which the water requirement is critical. Also, because of the irrigation interval, most of the fields from 1995 to 2005 were irrigated by gravity irrigation [7]. However, from 2005 to 2024 the use of drip irrigation will have increased exponentially [32].…”

“…The region of Tacna, located in southern Peru, has a water shortage, so it is important to carry out different types of studies for the water management of crops. The predominant tree crop is the olive tree [7]. The timing, duration and intensity of water restrictions significantly affect the growth and production of olive trees, affecting the process of fruit development [6,8].…”