Liu Yiwen, Shen Xiangjin, Zhang Jiaqi, Wang Yanji, Wu Liyuan, Ma Rong, Lu Xianguo, Jiang Ming
Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun China.
University of Chinese Academy of Sciences Beijing China.
Ecol Evol. 2023 Jan 18;13(1):e9755. doi: 10.1002/ece3.9755. eCollection 2023 Jan.
Sanjiang Plain is the largest marsh distribution area of China, and marshes in this region significantly affect regional carbon cycle and biodiversity protection. The vegetation phenology of marsh significantly affects the energy exchange and carbon cycle in that region. Under the influence of global climatic change, identifying the changes in phenology and their responses to climatic variation in marshes of Sanjiang Plain is essential for predicting the carbon stocks of marsh ecosystem in that region. Using climate and NDVI data, this paper analyzed the spatiotemporal variations in the start (SOS), end (EOS), and length (LOS) of vegetation growing season and explored the impacts of climatic variation on vegetation phenology in marshes of Sanjiang Plain. Results showed that the SOS advanced by 0.30 days/a, and EOS delayed by 0.23 days/a, causing LOS to increase significantly ( .05) by 0.53 days/a over marshes of Sanjiang Plain. Spatially, the large SOS advance and EOS delay resulted in an obvious increasing trend for LOS in northern Sanjiang Plain. The rise of spring and winter temperatures advanced the SOS and increased the LOS, and the rise in temperature in autumn delayed the EOS in marshes of Sanjiang Plain. Our findings highlight the necessity of considering seasonal climatic conditions in simulating marsh vegetation phenology and indicate that the different influences of climatic variation on marsh vegetation phenology in different regions should be fully considered to assess the marsh ecosystem response to climatic change in Sanjiang Plain.
三江平原是中国最大的沼泽分布区，该地区的沼泽对区域碳循环和生物多样性保护有着重大影响。沼泽植被物候显著影响该地区的能量交换和碳循环。在全球气候变化的影响下，识别三江平原沼泽物候的变化及其对气候变化的响应，对于预测该地区沼泽生态系统的碳储量至关重要。本文利用气候和归一化植被指数（NDVI）数据，分析了植被生长季开始时间（SOS）、结束时间（EOS）和长度（LOS）的时空变化，并探讨了气候变化对三江平原沼泽植被物候的影响。结果表明，三江平原沼泽的SOS以每年0.30天的速度提前，EOS以每年0.23天的速度推迟，导致LOS显著增加（P<0.05），增幅为每年0.53天。在空间上，SOS的大幅提前和EOS的推迟导致三江平原北部的LOS呈现明显的增加趋势。春季和冬季气温的升高使SOS提前并延长了LOS，秋季气温的升高则使三江平原沼泽的EOS推迟。我们的研究结果凸显了在模拟沼泽植被物候时考虑季节性气候条件的必要性，并表明在评估三江平原沼泽生态系统对气候变化的响应时，应充分考虑气候变化对不同区域沼泽植被物候的不同影响。
