ОңТҮстік қазақстан медицина академиясы, хабаршы №4 942, 2021 жыл, том 2

 
 
ОҢТҮСТІК ҚАЗАҚСТАН МЕДИЦИНА АКАДЕМИЯСЫ, ХАБАРШЫ №4(942, 2021 жыл, ТОМ 2 
 
 
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herbaceous plant species and short-rotation woody crops (SRWC) . Firstly, the change of land from intensive 
annual crop production to perennial herbaceous species or to SRWC progressively increases the content of 
soil organic matter. In contrast, shifting land from natural cover to intensive annual crop production typically 
decreases soil organic matter steadily. Secondly, the roots of perennial crops protect soil from erosion. 
Thirdly, these crops generally require less fertilizer, pesticide and less energy input for crop management, 
especially since it is not necessary to plow the field each year. 
Today, there is already some use of 
short-rotation woody crops 
for industrial purposes. For example, 
eucalyptus trees are grown for pulp markets and to supply charcoal for the steel industry in Brazil. In Europe 
and the United States, poplar trees are cultivated to provide fiber for the pulp and paper industry. 
Nevertheless, efforts to evaluate and develop energy crops are still in a relatively early stage of development 
when compared to conventional crops where cultivation and plant breeding has been under way for many 
years. The relatively early phase of energy crop development reflects a situation where tremendous 
opportunities exist to use advanced plant science and agronomy to dramatically increase biomass yields. 
In temperate climates the cultivation of 
willow 
(
Salix 
sp.) is suitable as SRWC. Willow trees and 
shrubs are very productive. In short-rotation coppice (SRC) plantations they can achieve high biomass yields 
by harvesting the young sprouts. The plant quickly regenerates with vigorous growth of new shoots and 
branches from the remaining tree trunks. SRWC can be harvested every few years. For instance, willows in 
SRC plantations can typically be harvested every 2–5 years over a period of some 20–25 years. Research on 
genetics and breeding has drastically increased the yields. In Europe most experience with willow plantations 
has been made in Sweden, where this crop is produced on approximately 14,000 hectares. 

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