2004-2015年湖北省植被NPP时空分布特征及其与气候因素关系

Spatiotemporal Distribution of Net Primary Productivity and Its Correlation with Meteorological Factors in Hubei Province from 2004 to 2015

为了探明湖北省植被NPP空间分布特征及其驱动机制,利用MOD17A3H NPP时序数据、土地覆盖类型产品MCD12Q1、气象数据和SRTM DEM地形数据等,采用线性趋势分析、相关系数等方法,分析了2004—2015年湖北省植被NPP时空分布特征,探讨了不同土地利用类型、不同地形条件下植被NPP分布及对气候因素的响应特征。结果显示:(1) 12年间,湖北省植被NPP总体呈上升趋势;植被NPP的空间分布大体呈东、西部山区高,中部略低的格局,全省植被NPP值大部介于400~600 g C/(m^2·a);(2)全省植被NPP与年均气温呈现正相关性的面积占全省总面积的79.28%,与年降水量呈现正相关性的面积占全省总面积的59.07%;(3)气温是影响林地、草地植被NPP变化的主要驱动因子,耕地主要受降水量影响;(4)植被NPP与年均气温和年降水量的相关性随高程、坡度、坡向的不同表现出差异性,植被NPP变化是气温、降水和地形条件综合作用的结果。

In order to clarify the changes and driving mechanism of the vegetation NPP(net primary productivity)in Hubei Province,based on MOD17 A3 H NPP time series data,MCD12 Q1,meteorological data and SRTM DEM,the spatial and temporal distribution characteristics of vegetation NPP in Hubei Province from 2004 to 2015 were studied by using linear trend analysis and correlation coefficient method.Furthermore,the distribution of vegetation NPP and its response to meteorological change were explored under different land use types and topographic conditions.The results showed that:(1)during the past 12 years,the vegetation NPP in Hubei Province showed overall upward trend,and it was generally higher in the eastern and western mountainous areas than that of the middle part of the study area;the mean annual NPP of the study area from 2004 to 2015 ranged from 400 g C/(m^2·a)to 600 g C/(m^2·a);(2)the areas where vegetation NPP was positively correlated with annual average temperature and annual precipitation accounted for 79.28%and 59.07%of the total area of the province,respectively;(3)air temperature was the main driving factor affecting the change of NPP in forestland and grassland;the NPP changes of farmland were mainly affected by precipitation;(4)due to elevation,slope and aspects,there were the significant differences of the correlations between the vegetation NPP and annual average temperature and annual precipitation.The changes of vegetation NPP were the results of the combined effects of air temperature,precipitation and terrain conditions.