Four Kinds Of Conifer's Photosynthesis And Transpiration Characteristic Research

This research made use of portable Li-6400 photosynthetic measure system with the open gas exchange system and pocket automatic weather station were carried on the research on 4 Kind of conifers,(Picea asperata,Pinus tabulaeformis,Sabina chinensis,Juniperus communis) , photosynthetic and transpiration characteristic were measured in east campus of Inner Mongolia Agricultural University. The result showed that:(1) 4 Kind of conifers photosynthetic rate and transpiration rate can be divided into two types, which are single-peak pattern and single-peak pattern, and they have significant midday depression. The photosynthetic rate and transpiration rate changes are Sabina chinensis > Pinus tabulaeformis > Picea asperata〉Juniperus communis .(2) 4 Kind of conifers photosynthetic rate and transpiration rate seasonal changes both are July>September>April. In April the photosynthetic rate is low because of the chlorophyll content of leaf is low in earlier stage; The luminous strength and atmosphere temperatures of July both accelerate photosynthesis highly; In September the photosynthetic rate descend gradually because of the decrepitude of the leaf in later stage. the humidity of atmosphere is low and cause the pore close and the transpiration rate descended.(3) The correlative coefficient of photosynthetic rate and the main infection environmental factor from big to small is Gs,Ca,PAR,RH,Ta;The correlative coefficient of transpiration rate and the main infection environmental factor from big to small is Gs,Ca,PAR,RH,Ta。(4) The capacity of daily transpiration decalescence and water release of 4 Kind of conifers seasonal changes both are July>September>April. The changes is Sabina chinensis > Pinus tabulaeformis >Picea asperata〉Juniperus communis ammong 4 Kind of conifers...