Land degradation by soil erosion and sedimentation within Sarata catchment, Republic of Moldova

Land degradation by geomorphological processes (soil erosion, gully erosion, landslides and

sedimentation) represents an important environmental threat all over the Republic of Moldova.

The main causes are related to the favourable natural conditions such as friable lithology,

typically hilly fragmentation or climatic aggressiveness on the background of a sustained human

impact developed in the last two centuries. Despite the widespread soil and water conservation

measures that have been implemented during the soviet period, following the Agricultural Real

Estate Act applied in 1991, a revival of these processes is easier to observe especially by means

of floodplains aggradation. Under these circumstances, our study aims to assess the

sedimentation rates on the floodplains and reservoirs and to establish the source area of the

eroded sediments as well as the responsible process. Based on field campaigns, we took

representative in-situ soil / sediment samples from floodplains and reservoirs all over the Sarata

catchment, including wind-blown samples from the intefluvial ridges. The laboratory analyses

consisted of physical and chemical features such as: weight, apparent density, texture, ph,

electrical conductibility, total organic carbon, inorganic carbon, organic matter, inorganic

nitrogen (N), total phosphorus (P), total potassium (K) and other macro elements (i.e. Na+,

Mg2+, Ca2+, and Cl-). The preliminary results show that the soil erosion remains an important

process not by quantity but by quality. This is related also to the widespread high efficiency of

gully erosion control measures that have been implemented. A secondary role, most often

neglected, is held by wind erosion