风沙灾害对策勒绿洲棉花光合特征的影响

Study on the Impact of Wind Sand Disaster on Photosynthetic Characteristics of cotton in Cele Oasis

为评估风沙灾害对策勒棉区棉花生长的影响,以新陆中21号为供试品种,2011年-2012年在新疆策勒荒漠草地生态系统国家野外科学观测研究站农民常规栽培模式田内对四个发育时段的棉花进行不同防风沙措施的对比观测试验。结果表明:四个发育时段,不同防风沙处理下生长的棉花净光合速率日变化都呈现双峰曲线型,有较明显的“光合午休”现象,不仅全天各时次Pn值大小表现为:网内>水洗>CK;而且在固定光强下测得的Pn值大小依次也为:网内>水洗>CK,计算其差值后发现越到后期防护网内的和自然状况下水洗的Pn值与自然状况的Pn值间的差值越大。表明该地区风沙通过挟沙风沙粒击打棉株,及附着于叶片上的降尘共同作用导致其外部形态和内部生理结构都受到损伤使棉株长势偏弱。

To estimate the effect of windy and dusty on growth of cotton during the flowering stage in Cele county, the field experiment was carried out by using the variety Xinluzhong 21 as the materials in the national field station for desert and grassland ecosystem during the 2011-2012. Three treatments were conducted including gauze covering (gauze), natural condition (CK) and washing without gauze (washing), the effect of wind-sand disaster on unit area cotton leaf on photosynthetic characteristic parameters was analyzed. The results showed that diurnal change curve of net photosynthetic rate of four development stages of cotton in three treatments was M-type, and obvious "noon break" phenomenon was presented. Not only Pn values of six to eight times a day showed the order of gauze > washing > CK;but also Pn values under the fixed light intensity measured are the same order. So, There are many effecting factors of damage in the photosynthetic characteristic parameters of cotton, such as the sand flow blew to the plant body directly for a long time and dust adhering to cotton in Cele Oasis.