| Spatial-temporal dynamics of precipitation use efficiency in grassland and its relationship with climate changes on Qinghai-Tibet Plateau |
|
View Fulltext View/Add Comment Download reader |
| |
| DOI：10.7606/j.issn.1000-7601.2019.05.33 |
| Key Words: precipitation use efficiency spatiotemporal dynamics grassland Qinghai-Tibet Plateau climate change Carnegie-Ames-Stanford Approach model |
| Author Name | Affiliation | | TONG Lin-jing | Department of Ecology, School of Life Science, Nanjing University, Nanjing, Jiangsu 210093, China | | LIU Yang-yang | Department of Ecology, School of Life Science, Nanjing University, Nanjing, Jiangsu 210093, China | | WANG Qian | Department of Ecology, School of Life Science, Nanjing University, Nanjing, Jiangsu 210093, China | | LI Xiao-yu | Department of Ecology, School of Life Science, Nanjing University, Nanjing, Jiangsu 210093, China | | LI Jian-long | Department of Ecology, School of Life Science, Nanjing University, Nanjing, Jiangsu 210093, China |
|
| Hits: 1099 |
| Download times: 661 |
| Abstract: |
| In this study, the Carnegie-Ames-Stanford Approach model was used to simulate the NPP of the Qinghai-Tibet Plateau from 2000 to 2013, PUE was calculated as the ratio of NPP to annual precipitation. Based on the measured data, meteorological data and land cover data, temporal and spatial distribution characteristics of PUE, PUE of different grassland type, and its response to climate change were also explored. The results showed: The PUE of the Qinghai-Tibet Plateau showed an increasing trend with fluctuation, with an annual increase rate of 0.0035 g·m-2·mm-1, and the average value of 14 a was 0.38 g·m-2·mm-1. The spatial distribution of PUE had obvious heterogeneity, and basically showed a decreasing pattern from the east to west. The grassland PUE mainly distributed between 0.2 and 0.4 g·m-2·mm-1, accounting for 55.63% of the total area of the Qinghai-Tibet Plateau. The areas where grassland PUE showed a decreasing trend mainly distributed in the northern and western regions of the Qinghai-Tibet Plateau, as well as the eastern border area. The regions showing increasing trend concentrated in the central and southern parts. The variation coefficient of PUE was between 0.07 and 0.85. The area with stable trend accounted for the largest area(43.43% of the total area), which mainly distributed in the Tanggula Mountains and Hengduan Mountains. The average PUE values of different grassland followed the order of: meadow(1.06 g·m-2·mm-1)>slope grassland(0.80 g·m-2·mm-1)>plain grassland(0.30 g·m-2·mm-1)>alpine and sub alpine meadow(0.29 g·m-2·mm-1)>dessert grassland(0.23 g·m-2·mm-1)>alpine and sub alpine grassland(0.094 g·m-2·mm-1). The grassland PUE was negatively correlated with precipitation but positively correlated with temperature. It was more responsive to precipitation. |
|
|
|