Spatial structure as a factor of stability of bioproduction functioning of steppe geosystems (on the example of Aituar steppe, the Southern Urals)

The dependence of the variability of landscape functioning on its spatial structure was studied on the example of the steppes of the southern Urals. The values of NDVI and its intra-seasonal variability were considered as functions of landscape, neighborhoods, and the configuration of stows. Field verification showed that NDVI can be used as an indicator of aboveground herbal phytomass. NDVI increments between time pairs were ranked by deviations from modal values. The stability of NDVI dynamics was characterized by the Shannon index through the ratio of repeatability of deviations from background increments. Statistical methods revealed a variation in the contributions of landscape organization factors to the dynamics of NDVI during the warm period. On the southern slopes and in the bottoms of gullies, the phytomass significantly deviates from the background due to the landscape. The degree of stability of NDVI dynamics depends on the position relative to boundaries of stows and their shape. In the central sectors of plateaus and deluvial plumes, the dependence on the background landscape dynamics weakens, and the contribution of positive reverse soil-phytocenotic relationships to the formation of phytomass increases.