植物生态学报 ›› 2010, Vol. 34 ›› Issue (3): 316-329.doi: 10.3773/j.issn.1005-264x.2010.03.009

• 研究论文 • 上一篇    下一篇

中国东部南北样带主要植被类型物候期的变化

余 振1; 孙鹏森1*; 刘世荣2   

  1. 1中国林业科学研究院森林生态环境与保护研究所, 北京 100091; 2中国林业科学研究院, 北京 100091
  • 收稿日期:2009-07-14 出版日期:2010-03-01 发布日期:2010-03-01
  • 通讯作者: 孙鹏森

Phenological change of main vegetation types along a North-South Transect of Eastern China

YU Zhen1; SUN Peng-Sen1*; LIU Shi-Rong2   

  1. 1Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, Beijing 100091, China; and
    2Chinese Academy of Forestry, Beijing100091, China
  • Received:2009-07-14 Online:2010-03-01 Published:2010-03-01
  • Contact: SUN Peng-Sen

摘要: 植被物候期的变化是全球变化研究的热点问题, 因为物候过程是反映植被对气候变化响应的最直接和最敏感的生态学过程之一, 大尺度植被物候学过程主要以植被的季节动态体现其对气候变化的长期适应过程。基于NOAA/AVHRR从1982年至2006年的双周归一化植被指数NDVI (Normalized Difference Vegetation Index)数据, 依托中国东部南北样带, 对主要植被类型的物候过程进行模拟, 并计算了主要物候现象(包括返青起始期、休眠起始期和生长季长度)的发生时间和演变趋势。结果表明: 返青起始期显著提前的植被有温带针叶林(TCF, 0.56 d·a–1)、温带草丛(TG, 0.66 d·a–1)、亚热带热带针叶林(STCF,0.46 d·a–1)、亚热带落叶阔叶林(SDBF, 0.58 d·a–1)和亚热带热带草丛(STG, 0.89 d·a–1); 休眠起始期显著推迟的植被有寒温带温带针叶林(TCTCF, 0.32 d·a–1)、SDBF (0.80 d·a–1)和温带落叶阔叶林(TDBF, 0.18 d·a–1); 此外, 大部分植被类型的生长季长度都有所延长, 但延长的方式不同: TCF (0.77 d·a–1)是由于返青起始期显著提前造成的; TCTCF (0.38 d·a–1)和TDBF (0.36 d·a–1)是由于休眠起始期显著推迟造成的; TG (0.76 d·a -1)、STCF (0.83 d·a–1)、SDBF (1.40 d·a–1)和STG (1.30 d·a–1)等是由于返青起始期提前和休眠起始期推迟共同造成的。对温度和降水的变化进行分析发现, 温度对南北样带上植被物候的影响较大, 而降水对物候的影响相对较小, 不同植被类型对温度的响应各异。在南北样带上存在的热量梯度, 使得整条样带上植被的物候现象也表现出时间梯度, 从返青起始期发生的时间上比较, 从北向南逐渐推迟, 即寒温带植被>温带植被>亚热带植被; 休眠起始期和生长季长度则正好相反, 亚热带植被>温带植被>寒温带植被。

Abstract:
Aims Vegetation phenology is a sensitive indicator of ecological response to climate change that is usually used as an important component of dynamic vegetation models and reflects dynamic of carbon and water exchange between the land surface and the atmosphere.
Methods Based on the biweekly dataset of NOAA/AVHRR NDVI (Normalized Difference Vegetation Index) for 1982–2006, the phenological curves of main vegetation types along the North-South Transect of Eastern China (NSTEC) were extracted using remote sensing software ENVI (ver4.3, RSI). A smooth-splin method was used to simulate and develop smooth phonological curves, which were used to determine timing of main phenological events by the first derivative method.
Important findings Earlier onsets of green-up were found in Temperate Coniferous Forest (TCF, 0.56 d·a–1), Temperate Grassland (TG, 0.66 d·a–1), Subtropical and Tropical Coniferous Forest (STCF, 0.46 d·a–1), Subtropical Deciduous Broadleaf Forest (SDBF, 0.58 d·a–1), Subtropical and Tropical Grassland (STG, 0.89 d·a–1). Delays of dormancy were found in Temperate and Cold Temperate Coniferous Forest (TCTCF, 0.32 d·a–1), Subtropical Deciduous Broadleaf Forest (SDBF, 0.80 d·a–1) and Temperate Deciduous Forest (TDF, 0.18 d·a–1). Prolonged growing season lengths (GSL) were also found in most vegetation types in the transect; however, these differed in their onsets dates of green-up or dormancy. Prolonged GSL in TCF (0.77 d·a–1) was caused by earlier onset of green-up, prolonged GSL in TCTCF (0.38 d·a–1) and TDBF (0.36 d·a–1) were caused by delays of dormancy and prolonged of GSL in TG (0.76 d·a–1), STCF (0.83 d·a–1), SDBF (1.4 d·a–1) and STG (1.3 d·a–1) were due to both advances of green-up and delays of dormancy. Correlations among precipitation, temperature and NDVI were analyzed to further explore the causes of phenological variation. The result showed that temperature has greater
influence on variations of phonological events than precipitation. Heat gradient along NSTEC caused a phonological events gradient, i.e., a time sequence of cold temperate zone > temperate zone > subtropical zone in the
onset dates of green-up and subtropical zone > temperate zone > cold temperate zone in the onset dates of dormancy and growing season lengths.