A long-term and comprehensive assessment of the urbanization-induced impacts on vegetation net primary productivity

Xiaobin Guan; Huanfeng Shen; Xinghua Li; Wenxia Gan; Liangpei Zhang

doi:10.1016/j.scitotenv.2019.02.361

A long-term and comprehensive assessment of the urbanization-induced impacts on vegetation net primary productivity

Sci Total Environ. 2019 Jun 15:669:342-352. doi: 10.1016/j.scitotenv.2019.02.361. Epub 2019 Mar 3.

Authors

Xiaobin Guan¹, Huanfeng Shen², Xinghua Li³, Wenxia Gan⁴, Liangpei Zhang⁵

Affiliations

¹ School of Resource and Environmental Sciences, Wuhan University, Wuhan 430079, PR China.
² School of Resource and Environmental Sciences, Wuhan University, Wuhan 430079, PR China; Collaborative Innovation Center of Geospatial Technology, Wuhan 430079, Hubei, PR China. Electronic address: shenhf@whu.edu.cn.
³ School of Remote Sensing and Information Engineering, Wuhan University, Wuhan 430079, PR China.
⁴ School of Civil Engineering and Architecture, Wuhan Institute of Technology, Wuhan 430205, PR China.
⁵ Collaborative Innovation Center of Geospatial Technology, Wuhan 430079, Hubei, PR China; The State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing, Wuhan University, Wuhan 430079, PR China.

PMID: 30884259
DOI: 10.1016/j.scitotenv.2019.02.361

Abstract

Urbanization not only directly alters the regional ecosystem net primary productivity (NPP) through land-cover replacement, but it is also accompanied by huge indirect impacts due to the associated climate change and anthropogenic activities. However, to date, limited efforts have been made to quantitatively separate the two types of urbanization impacts, and the continuous variations over a long-time span are not well understood. In this study, both the long-term direct and indirect impacts of urbanization on NPP were established and analyzed based on multi-source remote sensing data, taking the city of Kunming in China as a case study area. The results indicated that the intense urbanization process has led to a continuous decrease in NPP from 1990 to 2014, due to the direct impact of land-cover replacement. Nevertheless, the urbanization has also resulted in an apparently positive indirect impact on NPP, which has offset about 30% of the direct impact in recent years. The increasing trend of the indirect impact was found to be higher than the NPP trend in the surrounding forest areas, which proves that vegetation growth has been promoted by the urban environment. The indirect impact has also shown great spatial and temporal heterogeneity, with generally higher values in the old city area and winter season. This can mostly be attributed to the distribution of temperature, i.e., the urban heat island effect, which has shown a significantly positive correlation with the indirect impact. However, the correlations between NPP and climatic factors were found to be completely different, which confirmed the need to separate the direct and indirect impacts. Overall, this study has demonstrated that urbanization has reduced the total NPP over the region, but has promoted some vegetation growth, and the knowledge of the indirect impact will help to support urban greening planning.

Keywords: Land-use/cover change; Net primary productivity; Remote sensing; Spatiotemporal analysis; Urbanization.

MeSH terms

China
Cities
Climate Change
Ecosystem
Environmental Monitoring*
Models, Theoretical
Seasons
Temperature
Urbanization / trends*