PROGRESS IN GEOGRAPHY ›› 2006, Vol. 25 ›› Issue (4): 58-67.doi: 10.11820/dlkxjz.2006.04.007

• Original Articles • Previous Articles     Next Articles

The Effects of Nitrogen Limitation on Ter r estr ial Ecosystem Carbon Cycle: a Review

REN Shujie1,2, CAO Mingkui1, TAO Bo1, LI Kerang1   

  1. 1. Institute of Geographical Sciences and Natural Resources Research, CAS, Beijing 100101, China|
    2. Graduate School of the Chinese Academy of Sciences (GSCAS), Beijing 100038
  • Received:2006-03-01 Revised:2006-06-01 Online:2006-07-25 Published:2006-07-25

Abstract:

Terrestrial carbon cycle and nitrogen cycle are closely coupled. Some factors, such as temperature, water and CO2 concentration, were more considered in the previous carbon researches than the nitrogen because of the complexity of nitrogen cycle, but this situation has changed in recent years. Nitrogen has great effects on the plant photosynthesis, organic matter decomposition, carbon allocation and the responses of ecosystem when the atmospheric CO2 concentration increases. There are generally three types of carbon models to consider nitrogen limitation on carbon assimilation: (1) static models: these type models usually use a constant soil fertility index or leaf nitrogen concentration and are fit for a site or district where the nitrogen variability can be neglected; (2) soil nitrogen limitation models: these models can maintain stable nitrogen budgets and dynamic soil nitrogen can turn the potential NPP to actual NPP; (3) leaf nitrogen limitation models: such models are similar to soil nitrogen limitation but feature a further dynamic leaf- level nitrogen regulation of NPP. The common approach uses relative leaf nitrogen concentration to scale down proportionally either the maximum Rubisco or the NPP. Although the three type models all consider the nitrogen effects on carbon cycle, they may produce great uncertainty in carbon research because of the partly understanding of the interaction between carbon and nitrogen. Future studies should focus on both the experiment and observation about the nitrogen feedbacks on carbon cycle and the development of integrated dynamic ecosystem models that can describe the interaction of carbon and nitrogen cycle, contributing to decreasing the uncertainty in the carbon research.

Key words: carbon cycle, limitation, model, nitrogen cycle, terrestrial ecosystem

CLC Number: 

  • P467