一次风沙过程对策勒绿洲棉花光合特性的影响

Effects of a Wind and Sand Weather Process on Photosynthetic Characteristics of Cotton in Cele Oasis

为评估一次沙尘天气对新疆绿洲棉花光合特性的影响机理及其危害过程,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以‘新陆中21号’为供试品种,对比观测受纱网保护(网内)和自然状况下生长(CK),及未受保护被水洗(水洗)3种处理下棉花在遭受一次风沙天气后,单位面积叶片上附沙量变化对棉花叶片净光合速率、气孔导度、胞间二氧化碳浓度和蒸腾速率等光合参数的影响。研究结果表明:不同防风沙处理的棉花在遭受沙尘天气后,净光合速率有明显下降,在受害后第18天左右降至最低,然后趋于平稳,且3种处理呈现相同的变化趋势,但整个沙尘过程单叶的净光合速率为网内>水洗>CK,且净光合速率与气孔导度、蒸腾速率呈明显的正相关关系,与胞间二氧化碳浓度呈明显的负相关关系;而叶片上的附沙量也呈随时间而减少的趋势,前期较快,后期趋于稳定,但各组分的变化略有不同。

In order to evaluate the influence mechanism of a wind and sand weather process on photosynthetic characteristics of cotton and its harm process in Xinjiang oasis, a field experiment was carried out on the variety of ＇Xinluzhong 21＇ in the national field scientific observation station for desert and grassland ecosystem, three treatments were conducted including guaze covering （guaze）, natural condition （CK） and washing without guaze （washing）, the effect of sand amount on unit area cotton leaf on net photosynthetic rate, stomatal conductance, intercellular COs concentration and transpiration rate was analyzed after a wind and sand weather process. The results showed that the net photosynthetic rate of different treatments decreased significantly after wind and sand weather, and reached the minimum at the 18^th day after injury, then kept at a stable level, the three treatments showed the same variation trend, but the net photosynthetic rate of per leaf showed the order of guaze 〉washing 〉CK, the net photosynthetic rate was significantly and positively correlated with stomatal conductance and transpiration rate, and significantly and negatively correlated with intercellular CO2 concentration; the sand amount on leaves decreased with the increase of time, and the change rate was high in the earlier stage and then reaehed a stable level, but the change of different components was different.