Journal of Geographical Sciences ›› 2011, Vol. 21 ›› Issue (4): 651-665.doi: 10.1007/s11442-011-0870-5

• Eco-environmental Studies • Previous Articles     Next Articles

Patterns and driving factors of WUE and NUE in natural forest ecosystems along the North-South Transect of Eastern China

SHENG Wenping1,2, REN Shujie1, YU Guirui1, FANG Huajun1, JIANG Chunming3, ZHANG Mi1,2   

  1. 1. Key Laboratory of Ecosystem Network Observation and Modeling, Synthesis Research Center of Chinese Ecosystem Research Network, Institute of Geographic Sciences and Natural Resources Research, CAS,Beijing 100101, China;
    2. Graduate University of Chinese Academy of Sciences, Beijing 100094, China;
    3. Institute of Applied Ecology, CAS, Shenyang 110016, China
  • Received:2010-10-26 Revised:2010-02-20 Online:2011-08-15 Published:2011-08-05
  • Supported by:

    National Natural Science Foundation of China, No.30590381; No.31000211; National Basic Research Program of China, No.2010CB833504


From July 2008 to August 2008, 72 leaf samples from 22 species and 81 soil samples in the nine natural forest ecosystems were collected, from north to south along the North-South Transect of Eastern China (NSTEC). Based on these samples, we studied the geographical distribution patterns of vegetable water use efficiency (WUE) and nitrogen use efficiency (NUE), and analyzed their relationship with environmental factors. The vegetable WUE and NUE were calculated through the measurement of foliar δ13C and C/N of predominant species, respectively. The results showed: (1) vegetable WUE, ranging from 2.13 to 28.67 mg C g-1 H2O, increased linearly from south to north in the representative forest ecosystems along the NSTEC, while vegetable NUE showed an opposite trend, increasing from north to south, ranging from 12.92 to 29.60 g C g-1 N. (2) Vegetable WUE and NUE were dominantly driven by climate and significantly affected by soil nutrient factors. Based on multiple stepwise regression analysis, mean annual temperature, soil phosphorus concentration, and soil nitrogen concentration were responding for 75.5% of the variations of WUE (p<0.001). While, mean annual precipitation and soil phosphorus concentration could explain 65.7% of the change in vegetable NUE (p<0.001). Moreover, vegetable WUE and NUE would also be seriously influenced by atmospheric nitrogen deposition in nitrogen saturated ecosystems. (3) There was a significant trade-off relationship between vegetable WUE and NUE in the typical forest ecosystems along the NSTEC (p<0.001), indicating a balanced strategy for vegetation in resource utilization in natural forest ecosystems along the NSTEC. This study suggests that global change would impact the resource use efficiency of forest ecosystems. However, vegetation could adapt to those changes by increasing the use efficiency of shortage resource while decreasing the relatively ample one. But extreme impacts, such as heavy nitrogen deposition, would break this trade-off mechanism and give a dramatic disturbance to the ecosystem biogeochemical cycle.

Key words: water use efficiency (WUE), nitrogen use efficiency (NUE), δ13C, C/N, North-South Transect of Eastern China (NSTEC)