## 3 Results  
### Spatiotemporal Dynamics of Territorial Space  
#### 3.1.1 Spatiotemporal Evolution of Territorial Space  
Table 5 outlines the evolving trends in territorial space utilization within the Dongting Lake region. From 2005 to 2020, the most pronounced transformations occurred in production space, while living space expanded considerably, and ecological space demonstrated relatively minor variability. Detailed examination of land-use types reveals the following: (1) Production space had an average share of 42.36% over the years. Agricultural production space declined with a dynamic rate of -0.21% during the study period. Industrial-mining production space exhibited exponential growth, with a dynamic degree of 32.28%, significantly surpassing other land-use types. These findings underscore the abundant natural resources in the region, supporting agricultural output and the growth of industrial and mining sectors. (2) Living space had an average share of 3.04% over the years. It expanded by 368.96 km\({}^{2}\) during the study period. Agricultural living space exhibited minimal change. The dynamic degree of urban living space dropped from 9.79% to 0.20%, reflecting reduced construction intensity as urbanization approached saturation. (3) Ecological space, the dominant land-use category, covered 54.60% of the total area. Both forest and grassland ecological spaces showed declining trends. Forest land dynamics increased by 177.21% during the period 2015-2020 compared to 2005-2010, while grassland dynamics declined by 98.03% in the latter period relative to the earlier one. Water ecological space fluctuated, first increasing and then declining, highlighting its instability in lake-intensive regions. Potential ecological space, often designated for future construction, expanded by 32.10% over the study period, with a dynamic degree of 2.14%. To better analyze territorial space evolution trends, this study uses maps to visualize the data from Table 5. As depicted in Figure 3, the left panel illustrates the spatiotemporal evolution characteristics of primary land-use categories. The enlarged sections on the right provide a detailed view of the distribution patterns for secondary land-use types. The results indicate that between 2005 and 2020, the Dongting Lake region displayed a \"U\"-shaped spatial structure, where ecological space surrounds production and living spaces. (1) Agricultural production space is mainly distributed in the lakeside plains, shaped by river network erosion, in the central and northern areas. During the study period, this category declined significantly in the lake-intensive zones of Jingzhou. In contrast, industrial-mining production space expanded continuously in suburban areas near the administrative centers of the five cities, taking advantage of urban construction land. This reflects the increasing demand for industrial-mining construction activities driven by urbanization. (2) Urban living space is clustered around the administrative centers of the five cities. Agricultural living space is dispersed in areas near rivers with favorable water and thermal conditions. Notably, urban living space in Changsha's Xiang River waterfront area exhibits a clear pattern of radial expansion, emphasizing an intensified waterfront clustering pattern as human activities increase. (3) Forest ecological space is primarily located in the peripheral hilly regions of Yueyang, Changde, Yiyang, and Changsha, acting as a crucial ecological buffer. Water ecological space is concentrated in the core area of Dongting Lake, mainly in the western parts of Yueyang and the northern plains. The observed patterns suggest that ongoing urbanization threatens water-centered ecosystems by exacerbating water pollution, degrading ecological habitats, and increasing carbon emissions. These impacts may hinder the coordination and development of territorial space.