Considerations on land use and land degradation in Jijia’s upper catchment (Hilişeu county)

Land degradation from Hilişeu county is mainly due to various erosion types, as areolar or liniar, but also by amplifying landslides (both with generalized spread). Also, land degradation is influenced by a considerable number of secondary processes whose is represented at punctual level. Soil cover, which is in direct contact with climatic factors, being strongly controlled by them, changes completely in its appearence and characteristics. On flat or slightly inclined surfaces, alteration products remain in place, contributing to the formation of eluvium that covers the sculptural interfluves. When the slope is increasing, alteration products start to move slowly. These processes are known as areolar erosion, depth erosion or wet landslides, processes that have an important role not only in the evolution of landscape, but also in the slope one. Their main reason is the force of gravity, but their mode of expression and their stage of development depends on a complex of natural and anthropogenic factors. The occurance of areas affected by current geomorphological processes on arable surface (occupying a total of 2502.02 ha), is associated with the dysfunctional land use and ineffective style of exploitation. By using GIS techniques applied to topographic maps and orthophotos, subsequently verified by field research, was conducted the diachronic analysis of the current land use, but also the statistical analysis specific to the digital cartographic reliance previous obtained

Determining Attribute—Response Relationships of Soils under Different Land Uses: A Case Study

Soil researchers are interested in a gaining better understanding of the soil system state by analyzing its properties and their dynamics in time as well as in relation to land use change. Tilled, abandoned, and forest soils were assessed regarding attribute–response relationships for the bulk density (BD), total porosity (TP), volumetric moisture (θv), and penetration resistance (PR) with the use of the interquartile ratio (IRI) integrated into a resilience formula and Shannon entropy indices. The IRI results differentiated soil properties according to agrotechnics (wheel track vs. between wheels) and the state of the system (tilled vs. abandoned vineyard). Entropy (En) indicated a high level of uncertainty for PR. The linear regression applied to the pairs of BD-TP, TP-θv, and PR-θv showed better results for the IRI weight (IRIweight) compared to the entropy weight (Enweight) for the soil between the wheels. The soil of the abandoned vineyard showed a faster tendency toward resilience that was more pronounced in the tilled wheel tracks than in the area between the wheels. The IRI can thus be an alternative to entropy in the evaluation of the response of some soil properties according to their use. When integrated into a resilience formula, the IRI can estimate the dynamics of soil properties for abandoned land compared to reference soil

Simulation of Rainfall Erosivity Dynamics in Romania under Climate Change Scenarios

Soil erosion is triggered by rainfall through the detachment of soil particles and their transport downslope, playing a key role in soil erosion models. Together with the vegetation cover, rainfall is a temporal dynamic factor, inducing corresponding time variations of erosion rates. Under current climate change, rainfall is also changing its characteristics and our study aimed to reveal whether these changes will significantly affect rainfall erosivity in Romania, and implicitly the soil erosion. To achieve this purpose, we developed a statistical non-parametric model for predicting rainfall erosivity on the basis on the modified Fournier index and applied it to future precipitation evolution scenarios. The precipitation data were extracted from the CHESLA database for the Romanian territory for two climate change contrasting scenarios (RCP 4.5 and 8.5). Average predictions from five selected climate models were used in order to minimize prediction uncertainty. The results show that rainfall erosivity is likely to increase, at least during the 2041–2060 period, especially in the south-western, western and eastern part of the country, which may cause a corresponding increase in soil erosion rates, with an average of 1–2 t ha−1 yr−1. During the 2061–2080 period, rainfall erosivity is likely to decrease in central and eastern Romania