Chin J Plant Ecol ›› 2013, Vol. 37 ›› Issue (10): 901-911.DOI: 10.3724/SP.J.1258.2013.00093

• Research Articles •     Next Articles

Interannual variation of rain-use efficiency of three coniferous forests and their response to meteorological factors in Liupan Mountains of Ningxia

WANG Yun-Ni,XIONG Wei(),WANG Yan-Hui,YU Peng-Tao,CAO Gong-Xiang,XU Li-Hong,ZUO Hai-Jun,HE Liang-Liang   

  1. Key Laboratory of Forestry Ecology and Environment of State Forestry Administration, Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, Beijing 100091
  • Received:2013-04-10 Accepted:2013-06-28 Online:2013-04-10 Published:2013-09-29
  • Contact: XIONG Wei

Abstract:

Aims Rain-use efficiency (RUE), the ratio of vegetation productivity to annual precipitation, is an important measure of water use and a key determinant of the net primary production (NPP) of forest ecosystems. Our objective is to investigate the interannual variation of RUE of three conifer forests and their response to the variation of meteorological factors.
Methods We calculated the biomass and NPP of three coniferous forests (Pinus armandii natural forest, Larix principis-rupprechtii plantation and Pinus tablaeformis plantation) in Liupan Mountains of Ningxia, China by dendroecological methods, empirical biomass equations and collected meteorological data including monthly air temperature, humidity and precipitation. Then we calculated the RUE of these forests and analyzed their correlation with meteorological factors.
Important finding The NPP and RUE of L. principis-rupprechtii plantation, having the values of 6.72 t·hm -2·a -1and 1.12 g·m -2·mm -1, respectively, were 1.53 and 1.49 times higher than the Pinus armandii natural forest and 0.17 and 0.15 times higher than the P. tablaeformis plantation, respectively. The RUE increased with forest age when it was younger than 32 years, but RUE varied among species. The interannual variation of RUE of P. armandii natural forest was relatively stable when aged 32-45 years and then decreased with age. With increasing annual precipitation, the RUE of P. armandii natural forest decreased, but the RUE of the two plantations increased at first and then decreased. The RUE of all three forests tended to be similar in the driest years and tended to have the same minimum value in the wettest years. RUE, which was affected by meteorological factors of the previous year, responded to meteorological factors differently among tree species, but it was mainly influenced by meteorological factors of the current year and its annual variation pattern. The RUE of P. armandii natural forest was significantly negatively correlated with precipitation in August of the previous year and that in September, October and November of the current year. The RUE of the two plantations was significantly correlated with precipitation in September of the previous year and that in April of the current year and, in the case of the L. principis-rupprechtii plantation, to precipitation in September of the current year. The RUE of all three tree species was significantly correlated with the mean air temperature in June and March of the current year and that in June of the previous year. In addition, the RUE of P. armandii natural forest was significantly correlated with air temperature in February of the previous year, and the RUE of the two plantations was significantly positively correlated with air temperature in April and May of the current year.

Key words: climate change, meteorological factors, net primary productivity (NPP), rain-use efficiency (RUE)