Soil loss monitoring of vineyards in the Gerecse Hills (Hungary), using UAV technology

The northern loess-covered part of the Gerecse belongs to the Ászár-Neszmély Wine Region, and is highly frequented by soil erosion. One of the largest vinery in the region recognized the problem and already makes efforts to cope with the natural degradation, but the exact measure of soil loss, and thus its cost, is yet unknown. In this project three vineyards were selected in the vicinity of Dunaszentmiklós village. Previous studies identified the most erosion-sensitive locations using satellite images, but to specify the soil erosion between the rows of grape vines, high resolution images were collected with UAV (Unmanned Aerial Vehicle). The images were used to create the digital surface model (DSM) and the orthophoto of the areas by means of photogrammetric analysis. The final resolution in which the soil loss was defined is 10 cm.

Since the summer of 2019 data have been collected in seasonal measurements. We used the USLE (Universal Soil Loss Equation) model [1] to determine the soil loss and its precise location. The focus was on the definition of the C (crop management) and the R (rainfall erosivity) factors because these change from season to season. The effect of the change of land cover as the summer turned into autumn was remarkable from the aspect of soil erosion. A similar change was observed in the weather impact: in this period more rain fell during the summer than in the autumn. According to the USLE model in the study area the rate of the soil loss was twice as high during the summer as in the autumn.

The vinery do its best to prevent soil erosion. One of their effective method is to sow grass among the vines. In this study a hypothetic model was also created to prove the importance of their method in the scale of the erosion. The most significant difference between the results of the model and the reality was observed in the summertime. Based on the hypothetic model the soil loss would be 3.5 times more if they would not take care of sowing grass in the vineyard.

The project was supported by the ÚNKP-19-2 New National Excellence Program of the Ministry for Innovation and Technology (from part of T. Takáts),  the Thematic Excellence Program, Industry and Digitization Subprogram, NRDI Office, project no. ED_18-1-2019-0030 (from part of G. Albert), and the  Hilltop vinery.

Data Sources:

Precipitation data from the OMSZ Hungarian Meteorological Service and the K factor (soil erodibility) from Pásztor et. al. [2] MTA ATK TAKI.

References:

[1] Wischmeier, W. H., & Smith, D. D. (1978). Predicting rainfall erosion losses- a guide to conservation planning. USA: USDA, Science and Education Administration.

[2] Pásztor, L., Waltner, I., Centeri, C., Belényesi, M., & Takács, K. (2016). Soil erosion of Hungary assessed by spatially explicit modelling. Journal of Maps, 1-8.