Modeling the impact of net primary production dynamics on post-disturbance Amazon savannization

Anais da Academia Brasileira de Ciências

MÔnica C.a. Senna¹  Marcos H. Costa¹  Eric A. Davidson¹  Carlos A. Nobre¹ 

关键词: Amazon;    climate;    deforestation;    ecosystem model;    net primary production;    savannization;    Amazônia;    clima;    desmatamento;    modelagem de ecossistemas;    produção primária líquida;    savanização;   

DOI  :  10.1590/0001-37652014108212

来源: SciELO

【 摘 要 】

Amazon tropical forests are being replaced by pasturelands and croplands, but they sometimes revert to regrowth forest when abandoned after a period of agricultural use. Research suggests that this secondary regrowth is limited by climate and nutrient availability and, using a coupled biosphere-atmosphere model, we investigated patterns in the regrowth of the Amazon rainforest after a full deforestation event, considering different types of nutrient stress. We found that, over a 50 year regrowth period, the reduction of precipitation caused by large-scale deforestation was not sufficient to prevent secondary forest regrowth, but this decrease in precipitation combined with nutrient limitation, due to logging and frequent fires, did indeed prevent forest regrowth in central and southern Amazonia, leading to a savannization. These results are concerning, as the northern Mato Grosso region has the highest clearing rate in Amazonia. The low resilience of the forest under nutrient stress indicates that a large scale disturbance could greatly expand the area suitable for cropland, accelerating forest disappearance.

【 授权许可】

CC BY   
 All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License