Net photosynthetic rates(Pn) were measured in 18-month-old seedlings of Machilus pauhoi from two provenances of Suichuan in Jiangxi and Jian’ou in Fujian using a LiCor LI-6400 portable photosynthesis system(LiCor Inc...Net photosynthetic rates(Pn) were measured in 18-month-old seedlings of Machilus pauhoi from two provenances of Suichuan in Jiangxi and Jian’ou in Fujian using a LiCor LI-6400 portable photosynthesis system(LiCor Inc.,Lincoln,NE,USA) with a LED light source. The other photosynthetic parameters,including maximum net photosynthetic rate(Pmax),apparent quantum yield(AQY),light saturation point(LSP) and light compensation point(LCP),were also detected in response to irradiation. The results showed: The average P max,AQY,LSP and LCP of the seedlings from the two provinces were 12.65 μmolCO2.m -2 s -1,0.052 7 μmolCO2.μmol -1 photons,1 120.99 μmol.m -2 s -1 and 18.03 μmol.m -2 s -1 respectively. There were significant differences between the two provenances in the all photosynthetic parameters except for AQY. The provenance of Suichuan performed better than that from Jian’ou with higher P max,AQY and LSP of 30.48%,4.66% and 25.70% respectively,though the LCP of Suichuan provenance was higher and needed stronger illumination. There was more variation in P max,AQY,LSP and LCP between the two provenances than that within the two provenances. There were significant differences between the upper and lower crown layers with higher P max and AQY in the upper crown,while there was no difference in LCP and LSP between the two crown layers due to the integrated influence of the shape of seedling crowns and the photosensitivity of leaves.展开更多
The sample plot investigation and stem analysis have been conducted so as to study the growth law of Machilus pauhoi and to analyze the relationship between its growth and the environments in Anfu county and Jian coun...The sample plot investigation and stem analysis have been conducted so as to study the growth law of Machilus pauhoi and to analyze the relationship between its growth and the environments in Anfu county and Jian county ,Jiangxi province The results indicate that:(1) Machilus pauhoi ,an indigenous tree species, grow quickly, but grow slowly in the early 5 years (2) According to average growth increment, the diameter at breast height of 50 year old tree is 0 64?cm·a -1 , its height is 0 45?m·a -1 and its volume is 0 0169?m 3·a -1 ; (3) In the growth process, there are two peak growth periods for it The peak growth periods of diameter at breast height are among the 15th～20th year and the 40th～45th year The peak periods of height are among the 5th～15th year and the 35th～40th year, and the peak periods of tree volume are among 20th～25th and 40th～45th year (4) The site condition has more influences on the early 20 years growth than on mid later term growth (5) The woodland in the 300～500?m’s altitude with slate forming soil, rich organic matter and slope angle under 25, is most suitable for its展开更多
文摘Net photosynthetic rates(Pn) were measured in 18-month-old seedlings of Machilus pauhoi from two provenances of Suichuan in Jiangxi and Jian’ou in Fujian using a LiCor LI-6400 portable photosynthesis system(LiCor Inc.,Lincoln,NE,USA) with a LED light source. The other photosynthetic parameters,including maximum net photosynthetic rate(Pmax),apparent quantum yield(AQY),light saturation point(LSP) and light compensation point(LCP),were also detected in response to irradiation. The results showed: The average P max,AQY,LSP and LCP of the seedlings from the two provinces were 12.65 μmolCO2.m -2 s -1,0.052 7 μmolCO2.μmol -1 photons,1 120.99 μmol.m -2 s -1 and 18.03 μmol.m -2 s -1 respectively. There were significant differences between the two provenances in the all photosynthetic parameters except for AQY. The provenance of Suichuan performed better than that from Jian’ou with higher P max,AQY and LSP of 30.48%,4.66% and 25.70% respectively,though the LCP of Suichuan provenance was higher and needed stronger illumination. There was more variation in P max,AQY,LSP and LCP between the two provenances than that within the two provenances. There were significant differences between the upper and lower crown layers with higher P max and AQY in the upper crown,while there was no difference in LCP and LSP between the two crown layers due to the integrated influence of the shape of seedling crowns and the photosensitivity of leaves.
文摘The sample plot investigation and stem analysis have been conducted so as to study the growth law of Machilus pauhoi and to analyze the relationship between its growth and the environments in Anfu county and Jian county ,Jiangxi province The results indicate that:(1) Machilus pauhoi ,an indigenous tree species, grow quickly, but grow slowly in the early 5 years (2) According to average growth increment, the diameter at breast height of 50 year old tree is 0 64?cm·a -1 , its height is 0 45?m·a -1 and its volume is 0 0169?m 3·a -1 ; (3) In the growth process, there are two peak growth periods for it The peak growth periods of diameter at breast height are among the 15th～20th year and the 40th～45th year The peak periods of height are among the 5th～15th year and the 35th～40th year, and the peak periods of tree volume are among 20th～25th and 40th～45th year (4) The site condition has more influences on the early 20 years growth than on mid later term growth (5) The woodland in the 300～500?m’s altitude with slate forming soil, rich organic matter and slope angle under 25, is most suitable for its
