## 1 Introduction  
The net primary productivity (NPP) of vegetation is defined as the gross quantity of green plant organic matter accumulated per unit time by photosynthesis, minus the remainder after autotrophic respiration [1, 2]. NPP is a key indicator by which to judge the carbon balance of an ecosystem [3, 4]. With the in-depth development of terrestrial ecosystem carbon cycle research, it is vital to investigate the spatiotemporal distribution of NPP and its driving factors for ecological protection [5, 6]. The study of the spatiotemporal distribution of NPP and its driving factors is a topical issue for research and is influenced by a variety of factors. Among them, the influence of climate change and human activities on NPP is more obvious. Climate change affects vegetation growth, which in turn affects NPP. Human activities emit large amounts of carbon dioxide and produce changes in land cover, which in turn have an impact on vegetation growth [7, 8]. Corresponding work has been carried out on different ecological regions of China. For example, [PERSON] et al. (2020) examined the spatiotemporal patterns of NPP in Anhui Province and its contribution to climatic factors and human activities from 2001 to 2016 [9]. [PERSON] et al. (2021) explored the spatiotemporal variation in NPP and its main drivers in the Hengduan Mountains from 2000 to 2015 [10]. [PERSON] et al. (2021) researched the NPP of the Tibetan Plateau from 2001 to 2017 using spatiotemporal analysis and explored the effects of climate, altitude and human activity NPP [11]. [PERSON] et al. (2022) explored the spatial and temporal variability and future trends of NPP in the Yangtze Delta region as well as the response mechanisms of NPP to various driving factors [12]. [PERSON] et al. (2023) explored the spatial and temporal variability of NPP, the climate and anthropogenic interactions on NPP impacts and the optimal characteristics of the driving factors in China from 2000 to 2020 [13]. Ordos City, as an energy supply city for 18 provinces and cities in China, solved the problem of tight coal energy supply and demand in the country in 2021. Ordos City has made an important contribution to securing the country's energy supply, but this has also created a range of environmental problems, e.g., the illegal discharge of coal gangue from abandoned mining pits and road dust pollution, etc. In recent years, China has given prominence to overall ecological civilization development and established sustainable development as a national strategy. In this case, it is scientifically relevant to further illuminate the changes in the ecosystem of Ordos City and to understand the degree of response of anthropogenic and natural factors to promote the creation of a national sustainable development agenda innovation demonstration zone [14]. Therefore, it is crucial to investigate the spatiotemporal distribution of NPP in Ordos City and its driving factors to manage carbon emissions scientifically and effectively. Therefore, this study explored the spatiotemporal distribution of NPP in Ordos City and its driving factors from 2000 to 2019. Firstly, a spatiotemporal analysis of NPP from 2000 to 2019 was conducted using NPP data to explore the trend in NPP in Ordos City. Secondly, a correlation analysis was conducted using CO\({}_{2}\) spatial grid data, statistical yearbook data and meteorological data to explore the factors affecting NPP. Finally, regression analysis was utilized to construct a regression model between the relevant factors and NPP to provide a possible NPP forecast. The main contributions of this paper are as follows: (1) We exploring the spatiotemporal distribution of NPP in Ordos City and its changing trends from 2000 to 2019. (2) A driving factor analysis on the changes in NPP in Ordos City is conducted from the perspectives of anthropogenic factors and natural factors. (3) The results of the driver analysis are combined with the construction of NPP-anthropogenic factor regression models and NPP-natural factor regression models.