半干旱黄土丘陵区沙棘的水分生理生态及群落特性研究

Study on the characteristics of water physiological ecology of seabuckthorn and the communities in the semiarid loess hilly region

1 977～ 1 998年在陕西吴旗、安塞半干旱黄土丘陵区对沙棘的水分生理生态及群落学特性进行了分析研究。试验结果表明 :( 1 )沙棘有一定的耐旱能力 ,为广生态幅植物 ;( 2 )沙棘生长迅速 ,竞争力强 ,第 3～ 4年即可形成茂密的单优群落 ,以后随着自然稀疏 ,能形成良好的灌木—草本群落 ;( 3)沙棘适应半干旱黄土丘陵区生境的水分生理生态特性是 :束缚水含量随干旱加剧而上升 ,束缚水与自由水比值随干旱加剧而增大 ,同时 ,在旱季 ,沙棘蒸腾强度减弱 ,叶水势降低 ,临界饱和亏增大 ,持水力增强。研究沙棘水分生理生态及群落特性为沙棘的抗旱造林、引种、育种、提高水分生产力及改善沙棘林的经营管理提供了科学依据。

The characteristics of water physiological ecology of seabuckthorn and the communities were studied in the semiarid Loess hilly region at Wuqi and Ansai Shannxi in 1977~1998.The following results are obtained:(1) Seabuckthorn has certain drought resistant capability,it is a plant of vastly ecological amplitude.(2) Seabuckthorn has the characteristics of fast growth and strong competence,after 3~4 years,it can form mono-dominant community,then,with natural thinning,it can form good shrub herb community.(3) The characteristics of water physiological ecology of seabuckthorn adaptation to the habitat of the semiarid loess hilly region are that:With drought fierce,bound water content and ratio of bound water to free water increase.In dry season,transpiration intensity of seabuckthorn decreases,leaf water potential lowers,critical saturation deficiency increases,water holding capacity strengthens.These provided scientific basic for drought resistant afforestation of seabuckthorn,introducing fine variety,breeding,enhancing water productivity and improving management and administration.