EVALUATING THE ECOLOGICAL AND ECONOMIC SITUATION OF FOREST ECOSYSTEMS IN THE ADJACENT AGRO-LANDSCAPES

Abstract

Along with other agricultural measures, the forest ecosystems and protective forest nurseries in general, protect the agro-ecosystems from various negative phenomena improving the water regime of the given area, decreasing the adverse effects of droughts and warm winds and enhancing the yield capacity of agricultural crops.

The results of two-year investigations are introduced which evidence that the forests of Tsovinar community at the Martuni forest enterprise established on the cleaned soilground of Lake Sevan, have had the role of protective forest nurseries for the crops cultivated in the agro-ecosystems of the adjacent Tsovinar community. Thus, creating favorable microclimate, the mentioned forests have promoted the regular crops growth and development, hence, increasing their yield capacity. The nearer the agro-ecosystem to the forest ecosystem is, the higher the yield capacity of the agricultural crops cultivated in that system is and vice versa; in similar conditions of agro-technical measures, the farther the agro-ecosystem from the forest strip is, the lower the productivity of the mentioned crops is.

At the same time, the investigations have shown that the favorable effect of the forest system on the productivity of agro-ecosystems deteriorates at the distance of 610 m, while the positive effect of the forests on the agro-ecosystems situated farther than 1000 m from the forest edge is practically equal to zero.

Upon the estimation of economic efficiency, it has been revealed that the highest effect of forest ecosystems on the productivity of agro-ecosystems has been observed in case of those situated at the distance of 310 m from the forest edge. In such conditions, the yield capacity of winter wheat has made 40.5 c/ha and the economic efficiency – 169.5 thousand AMD, besides the economic efficiency of potato has made 1 mln 224 thousand drams/ha, while in case of spring barley it makes 109.2 thousand drams/ha. Parallel to the increase of agrocenosis distance from the forest edge the favorable effect of the forest has fallen down: the economic efficiency of the crops cultivated within the distance of 600 m has become half as much, while at the distance of 1020 m it hasn’t been recorded at all.

When establishing field protective forest strips, the distance should be chosen not farther than 600 m from the forests, in which case, the forest strip will have the most favorable effect on the sustainability of agro-ecosystems and on the productivity increase in the crops of the given areas.