Impact of Field-Protective Forest Belts on the Microclimate of Agroforest Landscape in the Zone of Chestnut Soils of the Volgograd Region

Abstract

Protective afforestation at the regional level is aimed at ensuring optimal agroecological conditions on agricultural land, including the regulation of microclimate on agricultural land. However, the issue of seasonal variability of microclimatic indicators in the zone of the forest shelterbelt and in different soil and climatic conditions is insufficiently studied. The research purpose is to determine the seasonal influence of aerodynamic parameters of the forest belt on the complex of microclimatic factors in the zone of chestnut soils of southern Russia. The research object is represented with agroforest landscapes of the Kachalinskoe experimental farm of the Ilovlinsky district of the Volgograd region. The study area is typical for this region in terms of soil cover and structure of protective forest plantations. The paper presents the results of study of the microclimate in the openwork-structure forest belt of a 30-year old. The ameliorative influence of the forest belt is determined by its height and construction. We have studied the microclimate indicators, such as wind speed, soil temperature and moisture, air temperature and humidity. We have carried out their instrumental measurements in the forest belt and in the adjacent territory at distances of 3H, 5H, 8H, 10H, 15H, 20H, 25H, 30H (H is the height of the stand in the forest belt) from the forest belt. The measurements were made once a season (summer, autumn, winter) in three-time intervals during the day. The research has shown that positive influence of forest belt on soil temperature in spring and autumn periods is traced up to 10–15H, in winter period there is no influence. The most distinct influence was noted in summer observations, so the average difference of temperatures in summer at 15H in the in the forest belt was 28%; in autumn, the same difference was 15%. The positive influence on soil moisture in the autumn period is most clearly traced, so the average difference in soil moisture indicators near the forest belt and agrolandscape is 18% and 2% in the summer period. The average temperature difference near the forest belt and 20H is only 4%, and 1% in the summer period. Effective reduction of wind speed occurs at 25–30H in the summer season, 15H in the autumn, and 15H in the winter periods. The difference in wind speed near the forest belt and average temperature in the agrolandscape is 52% in summer, 40% in fall, and 30% in winter. The results obtained are an attempt to assess the ameliorative impact of the forest belt on microclimatic indicators under conditions of regional climate change, and to make adjustments in the applied agricultural technologies for cultivation of crops in the inter-belt space.