Analyses on Water Consumption Characteristics of Eucalyptus urophylla ×E. grandis,Cunninghamialanceolata and Cinnamomuncamphora
The sap flow densities of Eucalyptus urophylla×E. grandis, Cunninghamia lanceolata and Cinnamomun camphora plantations were measured over a period of five days using the Granier thermal dissipation probe method in the Guangxi Huang-mian Forest Farm. The sap flow flux, average daily water consumption and the relationship between the sap flow density and the main environmental factors were analyzed. Sap flow density of the three tree species coincided with the photosynthetically active radiation following a singleton curve pattern. Further analyses showed that E.urophylla×E.grandishad the strongest water consumption of the species. Although sap flow density of C. camphora was larger than that of C. lanceolata, its overall water consumption was the lowest as it had the smallest sapwood area and this resulted in its daily water consumption per tree being only 0.5 times that of C. camphora.For the latter, whilst its sapwood area was larger than that of E.urophylla×E.grandis, its water consumption amounted to only about 0.7 times of E.urophylla×E.grandis. All three species showed similar trends in water consumption in relation to photosynthetic active radiation (PAR), with water use in all three following unimodal curves. By partial correlation analyses it was found that the sap flow rates of the three species were related to photosynthetic active radiation, water pressure deficit; and, whilst there was a significant positive correlation between the flow ratesin C.camphora and C.lanceolata and relative air humidity, the same correlation for E.urophylla×E.grandis was not significant. The results of this sap flow and water consumption study on the three different tree species can provide a valuable reference for the selection of afforestation tree species in the region.
NETL
NSTL
万方数据
维普
