Investigation on factors involve in fading of important of trees in south Baluchistan.
1999
Afroziyan, Mehdi | Sadegie, Ebrahim | Salahi, Ali Azam | Rahbbar, Esmaeil
This research project investigaJe the factors causing wilting of important tree species including prosopis sp, Acacia nilotica, Cap paris decidua and Zizipus spina . christi. These factors include pests and diseases, precipitation rate and the soil physico . chemical properties also through collecting run off and surface water sqmples their elelctric conductivity and asididty and also the main componentes present in the precipitation and the main factors causing asid rains including soul/ate and nitrare and chloride were studied also the pricipal ca/iones such as calcium Manyasium were analysed. Filially the above mentioned factors were quantified and analysed by using the statistical method of multi . variable regression. The results obtained indivated that there was a positive correlation between. The soil humidity saturation and precipitation. The most important Limiting factor of the species growth was the rate of precipitation. The must be mentiolled that the rate of precipitation withill Last ten yeaers has decreased so as from a rate of 253i6mm in the gear 136.8 it has slumped to 32/9 in the year 1372. alSO the ph related to surface water indicates its alkalinity ranging from 7/6 to 7/9. Calcium and manyansium cations influence the aroa's surface water and their effect on the wate acidity is statistica\{r significamt, with calcium injluenciny most the /lext factor causing the species wilting are pests particularly [ignia vorous inseet pests are the most important factor accelerating the species wilting. the results obtained on the basis of the incubation of the cases being suspected of disease showed that no exotic pathogenic factor
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