Cui Linli, Shi Jun, Xiao Fengjin
Shanghai Ecological Forecasting and Remote Sensing Center, Shanghai Meteorological Bureau, Shanghai, 200030, China.
Qingpu Meteorological Station of Shanghai, Shanghai, 201700, China.
Carbon Balance Manag. 2023 Dec 21;18(1):26. doi: 10.1186/s13021-023-00245-x.
Vegetation phenology can characterize ecosystem functions and plays a key role in the dynamics of plant productivity. Here we investigated the changes in growing season metrics (start of growing season, SOS; end of growing season, EOS; length of growing season, LOS) and their relationships with net primary productivity (NPP) in forestland and grassland in China during 1981-2016.
SOS advanced, EOS delayed, LOS prolonged and NPP increased significantly in 23.7%, 21.0%, 40.5% and 19.9% of the study areas, with an average rate of 3.9 days decade, 3.3 days·decade, 6.7 days·decade and 10.7 gC m·decade, respectively. The changes in growing season metrics were obvious in Northwest China (NWC) and North China (NC), but the least in Northeast China (NEC). NPP was negatively correlated with SOS and positively correlated with EOS and LOS in 22.0%, 16.3% and 22.8% of the study areas, respectively, and the correlation between NPP and growing season metrics was strong in NWC, NC and Southwest China (SWC), but weak in NEC and South China (SC).
The advanced SOS, delayed EOS and prolonged LOS all contribute to the increased NPP in forestland and grassland in China, especially in NWC, NC and SWC. This study also highlights the need to further study the response of NPP to growing season changes in different regions and under the influence of multiple factors.
植被物候可以表征生态系统功能，并且在植物生产力动态中发挥关键作用。在此，我们研究了1981 - 2016年期间中国林地和草地生长季指标（生长季开始时间，SOS；生长季结束时间，EOS；生长季长度，LOS）的变化及其与净初级生产力（NPP）的关系。
在23.7%、21.0%、40.5%和19.9%的研究区域中，SOS提前、EOS推迟、LOS延长以及NPP显著增加，平均速率分别为每十年3.9天、3.3天、6.7天和10.7 gC·m·十年。生长季指标的变化在中国西北地区（NWC）和华北地区（NC）明显，但在东北地区（NEC）最小。在22.0%、16.3%和22.8%的研究区域中，NPP分别与SOS呈负相关，与EOS和LOS呈正相关，并且NPP与生长季指标之间的相关性在NWC、NC和中国西南地区（SWC）较强，但在NEC和中国华南地区（SC）较弱。
SOS提前、EOS推迟和LOS延长均有助于中国林地和草地NPP的增加，尤其是在NWC、NC和SWC。本研究还强调需要进一步研究NPP在不同区域以及多种因素影响下对生长季变化的响应。
