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By using this field , potted plants, seedlings drying experiments, and combined production test and other methods to improve the survival rate of afforestation and preservation Picea rate principles and techniques for a more systematic study , draw the following basic conclusions : ( 1 ) through the production trial found Picea diffuse Austin area in the alpine forest , site preparation by mechanical trenching method can improve the survival rate of 7% , increase afforestation survival rate of 25% , the amount of saplings grown by 30 % or more. Afforestation in the sand , using seat covered water , container seedling planting and other measures to improve the survival rate of 20% to 30%. ( 2 ) Block of water through the membrane test results show that , compared with the control seat water film to increase soil moisture content of 2.0% to 2.5 %, the average increase in temperature 1 ~ 2 ℃. Health 2a , 3a and 4a raw raw survival rate of seedlings increased by 25% compared with the control , respectively , 21.4 % and 23.8% , respectively, compared with the control seedling height growth by 26 %, 44 % and 22% . ( 3 ) A pot experiment results showed that Picea seedlings under physiological conditions in sandy soil moisture limit 3.11% . In loam conditions of 3.96% . ( 4 ) seedling drought drying test results show that the growth of seedlings Picea seedlings with lower water content and weakened in the drying process, dehydration resulting seedling survival rate of seedlings decreased . Compared with pine , two species of seedlings under drought stress on water preservation and loss situation is basically the same stage of Picea seedlings to water conservation and dissipation capacity slightly larger than the pine seedlings .
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