摘要
温度在调节植被物候的变化中起着重要作用,气候变暖和城市化均会对温度产生影响进而影响植被物候。基于京津冀地区2001—2020年的归一化植被指数(NDVI)时间序列影像,参照物候观测站点监测数据,采用动态阈值法提取出研究区关键物候参数,即生长季始期(SOG)、生长季结束期(EOG)和生长季的长度(LOG),分析近20年京津冀地区耕地、林地、草地不同植被的物候时空变化特征及其城乡差异,从而探讨植被物候对城市化的响应。结果表明:(1)耕地SOG分布呈现双波峰现象,林地和草地的SOG相对集中,3种植被的EOG的分布均较为集中;2001—2020年京津冀大部分地区的SOG提前,EOG推迟,LOG呈现延长的态势。(2)从城乡梯度物候差异的空间分布特征来看,整体而言耕地、林地、草地3种植被类型的城区物候与农村相比都存在SOG提前,EOG推迟的情况,并且城区与农村的物候差异幅度要明显大于城乡过渡带与农村的物候差异。(3)从城乡梯度物候差异的时间分布特征来看,2001—2020年间,研究区中新老城区、城乡过渡带和农村的SOG提前,EOG推迟,LOG延长,但耕地、林地、草地3种植被物候参数的城乡差异在逐年减小。(4)城乡温度差异越大,SOG提前的幅度越大,EOG推迟的幅度也越大。城乡春季温差每增加1℃,林地和草地的城乡SOG差异将分别增加9.44d(P<0.05)、10.66d(P<0.01);城乡秋季温差每增加1℃,林地和草地的城乡EOG差异将分别增加13.03d(P<0.05)、7.15d(P<0.01)。
Temperature plays an important role in regulating the changes of vegetation phenology.Both climate warming and urbanization will affect temperature and thus affect vegetation phenology.Based on the Normalized Difference Vegetation Index(NDVI)time series images of the Beijing-Tianjin-Hebei(BTH)region from 2001 to 2020,referring to the monitoring data of phenological observation stations,the dynamic threshold method was used to extract the key phenological parameters of the study area,namely the Start of Growing Season(SOG)and the End of Growing Season(EOG),and the Length of Growing Season(LOG).This paper discussed the response of vegetation phenology to urbanization by analyzing the temporal and spatial variation characteristics and urban-rural differences of different vegetation in cropland,forestland and grassland in BTH in recent 20 years.The results showed that:(1)the distribution of SOG dates in cropland showed a double peaks phenomenon,the SOG dates of forestland and grassland were relatively concentrated,and the distribution of EOG dates of the three types of vegetation were relatively concentrated;from 2001 to 2020,SOG dates in most areas of BTH were advanced and EOG dates were delayed.LOG presented an extended trend.(2)The spatial distribution characteristics of phenological differences in urban-rural gradients indicated that on the whole,there were SOG advanced and EOG delayed in urban phenology of cropland,forestland and grassland compared with rural areas,and the phenological difference between urban and rural areas was significantly greater than that between suburban transitional zones and rural areas.(3)The temporal distribution characteristics of the phenological difference of urban-rural gradient during 2001—2020 showed that the SOG was advanced,the EOG was delayed and the LOG was prolonged in the study area including the new and old urban areas,suburban transitional zones and rural areas,but the urban-rural difference of phenological parameters of cropland,forestland and grassland was decreasing
作者
张聪聪
孟丹
李小娟
ZHANG Congcong;MENG Dan;LI Xiaojuan(College of Resources Environment and Tourism,Capital Normal University,Beijing 100048,China;Beijing Laboratory of Water Resource Security,Beijing 100048,China;State Key Laboratory Incubation Base of Urban Environmental Processes and Digital Simulation,Beijing 100048,China;Beijing Municipal Key Laboratory of Resources Environment and Geographic Information System,Beijing 100048,China)
出处
《生态学报》
CAS
CSCD
北大核心
2023年第1期249-262,共14页
Acta Ecologica Sinica
基金
北京市社会科学基金重大规划项目(21ZDA04)。
关键词
城市化
全球气候变暖
植被物候
动态阈值
urbanization
global warming
vegetation phenology
dynamic threshold
