Biological Features and Forage Performance of Black Saxaul (Haloxylon Aphyllum (Minkw) Iljin) in the Central Asian Desert

Abstract

Haloxylon aphyllum (Minkw.) Iljin is a treelike shrub from the Chenopodiaceae family with a thick, gnarled, highly branched trunk with dark gray bark. It is propagated by seeds. The most typical conditions of natural habitat are valley-like depressions of ridges and hollows of hilly sands, valleys and channels of old rivers, often with more or less close groundwater occurrence, as well as takyrs and takyr-like serozem soils. Black saxaul has a powerfully developed, deeply penetrating root system that reaches the level of groundwater or moist soil layers. The eaten part of black saxaul in the autumn-winter period is annual shoots, last year's twigs, fruits. It contains 10-12 % protein (in fruits up to 20 %), 2.2-2.7 % fat, 21.2-38.6 % ash substances, up to 39.3 % nitrogen-free extractive substances and up to 14.9 % fiber. At the age of five to six years, the plant height reaches 4-6 m, and the root system deepens by 14-16 m. Productive longevity is 35-45 years. It begins to vegetate in late March - early April with development of generative shoots. Flowering coincides with development of generative shoots. The flowering period lasts 10-20 days. Black saxaul, depending on the growing conditions, enters the fruiting phase in the 2-4th year of life. When creating pasture shelter strips, forage productivity on adjacent natural pastures at a distance of up to 100 m increases by 20-30 %. In the strip itself, the yield of small grasses increases 2-3 times. The total forage productivity of pastures improved by crops of black saxaul considering the yield of adjacent pastures, increases 2 times.