A Systematic Review on Digital Soil Mapping Approaches in Lowland Areas

Abstract

Digital soil mapping (DSM) around the world is mostly conducted in areas with a certain relief characterized by significant heterogeneities in soil-forming factors. However, lowland areas (e.g., plains, low-relief areas), prevalently used for agricultural purposes, might also show a certain variability in soil characteristics. To assess the spatial distribution of soil properties and classes, accurate soil datasets are a prerequisite to facilitate the effective management of agricultural areas. This systematic review explores the DSM approaches in lowland areas by compiling and analysing published articles from 2008 to mid-2023. A total of 67 relevant articles were identified from Web of Science and Scopus. The study reveals a rising trend in publications, particularly in recent years, indicative of the growing recognition of DSM’s pivotal role in comprehending soil properties in lowland ecosystems. Noteworthy knowledge gaps are identified, emphasizing the need for nuanced exploration of specific environmental variables influencing soil heterogeneity. This review underscores the dominance of agricultural cropland as a focus, reflecting the intricate relationship between soil attributes and agricultural productivity in lowlands. Vegetation-related covariates, relief-related factors, and statistical machine learning models, with random forest at the forefront, emerge prominently. The study concludes by outlining future research directions, highlighting the urgency of understanding the intricacies of lowland soil mapping for improved land management, heightened agricultural productivity, and effective environmental conservation strategies.

Editorial of the Special Issue Digital Soil Mapping, Decision Support Tools and Soil Monitoring Systems in the Mediterranean

“…The study revealed a trend of soil organic matter depleting over time, highlighting the need for soil conservation and restoration actions. With the latest accepted review paper, Adeniyi et al [37], conducted a systematic review of digital soil mapping application in lowland areas, emphasizing the growing recognition of the pivotal role of digital soil mapping in understanding soil properties in agricultural lowlands. These studies collectively demonstrate the capacity of machine learning models to advance our ability to assess spatial distribution of soil properties (e.g., electrical conductivity soil organic carbon content and stocks), thereby providing valuable insights for sustainable land management, agricultural productivity, and environmental conservation strategies.…”