Long-term impact of rainfed agricultural land abandonment on soil erosion in the Western Mediterranean basin

Abstract

Land abandonment is widespread in the Mediterranean mountains. The impact of agricultural abandonment results in a shift in ecosystem evolution due to changes in soil erosion, but little is known about long-term soil and water losses. This paper uses 11 years of measurements in two paired plots (abandoned vs control) with four subplots to determine how soil and water losses evolved after abandonment within an agricultural parcel. For two years (2004–2005) both plots were under tillage, and after 2006 one plot was abandoned. The monitored plots measured runoff and sediment concentration after each rainfall event. The results show that during the two years after abandonment there was an increase in sediment yield followed by a decrease. Once the field was abandoned, a sudden increase in runoff (× 2.1 times) and sediment concentration (× 1.2 times) was found due to the lack of vegetation and tillage. After one year, the sediment concentration and, after two years, the runoff rates were lower in the abandoned than in the tilled plots. This short transition period ended in contrasting responses between the control and abandoned plot as the impact of abandonment resulted in 21 times less sediment yield after nine years of abandonment. This occurred despite the fact that the year after the abandonment the abandoned plot had 2.9 times more erosion due to low vegetation recovery and the development of a soil crust. Agriculture land abandonment resulted in lower erosion rates over the long term, but showed an increase in soil and water losses over the short term (two years). Therefore, in the first two years after abandonment there is a particular need to apply nature-based soil and water conservation strategies to prevent soil erosion.

Long-term organic farming on a citrus plantation results in soil organic carbon recovery

“…Most of these changes occur because organic farming improves soil fauna (Crittenden et al, 2014) and natural soil fertility (Bowles et al, 2014). Organic farming reduces soil losses and promotes the use of catch crops, mulches, weeds or chipped pruned branches (Kirchhoff et al, 2017;Cerdà et al, 2018a). Increased plant and litter input reduces losses of soil and SOC, and promotes soil fertility and soil resilience.…”

Determining the spatial distribution of soil properties using the environmental covariates and multivariate statistical analysis: a case study in semi-arid regions of Iran

“…In arid and semi-arid areas, vegetation patterns and pedogenesis are highly affected by extreme climate conditions, and also by the topography (Jia et al, 2017;Cerdà et al, 2018). Flat areas, such as alluvial fans, valleys or lagoons, that are highly exposed to high peaks of insolation, register high average temperatures with prolonged dry seasons that enhance high evapotranspiration rates (Li et al, 2016), the difficulties of organic matter consolidation (Wang et al, 2016), the generation of soil crusts (Singer and Shainberg, 2004) and the reduction of available water for the plants (Amare et al, 2014).…”

Influence of Abandoning Agricultural Land Use on Hydrophysical Properties of Sandy Soil

“…On the other hand, in the analyzed case, increasing the values of CSMC and the high increase in water repellency occurred as a result of abandoning agricultural production and the succession of forest vegetation with a dominance of pine. The hydrological consequences of SWR have also been indicated by other authors [66][67][68][69][70][71][72]. According to studies of Butzen et al [73] on coniferous forest sites in Germany, water repellency effects were an important factor triggering overland flow generation.…”