Comprehensive Assessment of the Effect of Urban Built-Up Land Expansion and Climate Change on Net Primary Productivity

Abstract

Urbanization is causing profound changes in ecosystem functions at local and regional scales. The net primary productivity (NPP) is an important indicator of global change, rapid urbanization and climate change will have a significant impact on NPP, and urban expansion and climate change in different regions have different impacts on NPP, especially in densely populated areas. However, to date, efforts to quantify urban expansion and climate change have been limited, and the impact of long-term continuous changes in NPP has not been well understood. Based on land use data, night light data, NPP data, climate data, and a series of social and economic data, we performed a comprehensive analysis of land use change in terms of type and intensity and explored the pattern of urban expansion and its relationship with NPP and climate change for the period of 2000–2015, taking Zhengzhou, China, as an example. The results show that the major form of land use change was cropland to built-up land during the 2000–2015 period, with a total area of 367.51 km2 converted. The NPP exhibited a generally increasing trend in the study area except for built-up land and water area. The average correlation coefficients between temperature and NPP and precipitation and NPP were 0.267 and 0.020, respectively, indicating that an increase in temperature and precipitation can promote NPP despite significant spatial differences. During the examined period, most expansion areas exhibited an increasing NPP trend, indicating that the influence of urban expansion on NPP is mainly characterized by an evident influence of the expansion area. The study can provide a reference for Zhengzhou and even the world's practical research to improve land use efficiency, increase agricultural productivity and natural carbon sinks, and maintain low-carbon development.

Dynamic Changes, Spatiotemporal Differences and Factors Influencing the Urban Eco-Efficiency in the Lower Reaches of the Yellow River

“…Affluence and technological progress positively affect urban eco-efficiency, but the industrial structure and investment intensity hinders the improvement of the urban eco-efficiency, which is consistent with previous research results [ 33 , 68 , 73 , 74 ]. In contrast to relatively developed urban areas [ 75 ], the intensity of foreign investment hinders the optimization of urban eco-efficiency in the lower reaches of the Yellow River, mainly because the industrial transfer introduced by the cities in the lower reaches of the Yellow River is related to industries with high consumption and a low production capacity.…”

Synergistic Evaluation and Constraint Factor Analysis on Urban Industrial Ecosystems of Traditional Industrial Area in China

“…Despite this, it is still necessary to take measures from multiple dimensions to increase support for industrial ecology. For example, we should improve the construction of innovative ecosystems [49], strengthen the support for ecological elements such as land [50], and take consideration of responses to climate change [51,52]. We must break the information barriers among research institutions, universities, government departments, business organizations, and financial institutions, optimize the business environment, strengthen policy guidance, and actively promote the integration of industry-education-research and the transformation of research outcomes, thus to form a marketoriented and enterprise-based innovation system.…”

An inversion model for estimating the negative air ion concentration using MODIS images of the Daxing’anling region

“…Data acquired through remote sensing technology is of an outstanding space-time coverage and continuity, making it suitable for monitoring vegetation indexes and climate conditions [ 34 , 35 ]. Vegetational covers and climate changes can be broadly, simply, and efficiently measured through vegetation index; this may have certain correlations with the formation of NAI in nature while no relevant literature has been found up to now.…”