This paper reports the first photosynthetic study of marestail in Jiuzhaigou. In this work, we used PAM fluorometry to examine photosynthetic rates of submerged and emerged marestail in three lakes. Three lakes were s...This paper reports the first photosynthetic study of marestail in Jiuzhaigou. In this work, we used PAM fluorometry to examine photosynthetic rates of submerged and emerged marestail in three lakes. Three lakes were studied across a gradient of water temperature, with low water temperature conditions in Grass Lake and Arrow Bamboo Lake, and higher water temperature in Five Colored Lake. In the field, electron transport rates （ETRmax） were measured as rapid light curves （RLCs） by in situ yield measurements. Submerged and emerged marestail showed higher photosynthetic activity in Five Colored Lake compared to the other lakes, a response consistent with the adaptation of marestail in Five Colored Lake to high water temperature. The optimal temperature for photosynthesis of submerged marestail in Jiuzhaigou was about 12 ~C. Non- photochemical quenching （NPQ） of submerged and emerged marestail increased with increasing water temperature. Maximum quantum yield （Fv/Fm） of submerged marestail in Five Colored Lake showed full recovery at 170o h due to higher NPQ. Further, the chlorophyll a for submerged marestail was the highestin Grass Lake and the lowest in Five Colored Lake. These results indicate that in different lakes the function of these aquatic plants is associated with a diversity of place-dependent environmental conditions, especially water temperature that leads to pronounced differences in the plant＇s ecophysiological reactions.展开更多
基金funded by the International Program of the Ministry of Science and Technology of China (2010DFA91280)111 Project(B08037)
文摘This paper reports the first photosynthetic study of marestail in Jiuzhaigou. In this work, we used PAM fluorometry to examine photosynthetic rates of submerged and emerged marestail in three lakes. Three lakes were studied across a gradient of water temperature, with low water temperature conditions in Grass Lake and Arrow Bamboo Lake, and higher water temperature in Five Colored Lake. In the field, electron transport rates （ETRmax） were measured as rapid light curves （RLCs） by in situ yield measurements. Submerged and emerged marestail showed higher photosynthetic activity in Five Colored Lake compared to the other lakes, a response consistent with the adaptation of marestail in Five Colored Lake to high water temperature. The optimal temperature for photosynthesis of submerged marestail in Jiuzhaigou was about 12 ~C. Non- photochemical quenching （NPQ） of submerged and emerged marestail increased with increasing water temperature. Maximum quantum yield （Fv/Fm） of submerged marestail in Five Colored Lake showed full recovery at 170o h due to higher NPQ. Further, the chlorophyll a for submerged marestail was the highestin Grass Lake and the lowest in Five Colored Lake. These results indicate that in different lakes the function of these aquatic plants is associated with a diversity of place-dependent environmental conditions, especially water temperature that leads to pronounced differences in the plant＇s ecophysiological reactions.
