Photosynthetic response of Spartina alterniflora to shading and mowing
To reveal the photosynthetic response mechanism of Spartina alterniflora to shading and mowing,we in-vestigated the effects of different treatments(0％shading+no mowing,0％shading+mowing,30％shading+no mowing,30％shading+mowing,50％shading+no mowing,50％shading+mowing,70％shading+no mow-ing,70％shading+mowing,90％shading+no mowing,90％shading+mowing)on the photosynthetic charac-teristics of S.alterniflora.Seven photosynthesis-related indices were measured,including daily average photosyn-thetic rate,maximum net photosynthetic rate,light compensation point,dark respiration rate,chlorophyll a,chlo-rophyll b,and carotenoids.The results showed that shading significantly inhibited daily average photosynthetic rate(P＜0.01),which decreased with increasing shading intensity.The contents of chlorophyll a and carotenoids in-creased significantly with increasing shading intensity(P＜0.01).Mowing significantly inhibited daily average pho-tosynthetic rate,chlorophyll a,chlorophyll b,and carotenoid content(P＜0.01).Shading and mowing interacted to affect light compensation point of S.alterniflora(P＜0.05),but did not affect other indices.Principal component analysis revealed that the combination treatment of 90％shading and no mowing exhibited the strongest inhibition on photosynthetic activities of S.alterniflora.
万方数据
维普
