Progress and trends of China’s land consolidation engineering technologies based on patentimetrics and bibliometrics analysis

Land consolidation is a crucial approach to addressing the conflicts between people and land, resolving land use issues, and promoting rural revitalization. The advancement of land consolidation engineering technology is essential for the protection of farmland, the promotion of industrial development, and the enhancement of the human settlement environment. This study analyzes 3,439 invention patents and 3,392 references related to land consolidation engineering. Using bibliometric and semantic analysis methods, it explores the subjects of research and development, identifies hotspots and trends, and anticipates future directions for research and development in land consolidation engineering. According to the Land Consolidation Blue Book: China Land Consolidation Development Research Report No. 4, China's land consolidation has undergone a transition from land consolidation 1.0 to land consolidation 4.0. During this period, the number of land consolidation patents issued in China increased year by year, showing an overall exponential growth trend. It has experienced slow, steady and rapid growth stages. As far as inventors and invention institutions are concerned, although there are influential scholars and institutions in land consolidation inventions, land consolidation patent inventions are still sporadic and scattered. The collaboration network of land consolidation patent inventors exhibits a distribution pattern characterized by primary concentration with secondary dispersion. Compared with enterprises, inventors from universities and research institutes cooperate more closely, but the scale of the cooperation network is smaller. In the process of land consolidation technology change, three major development paths have been formed: (1) Research and development of methods and equipment for implementation of soil consolidation: focusing on the invention of structural components and equipment directly related to engineering implementation; (2) Research and development of soil improvement technology: focusing on the remediation of contaminated soil (including soil passivation and soil stabilization), soil fertility improvement, desertification land management and, and saline-alkali soil improvement. The results of the patent research and development keyword timeline show that with the passage of time, the keywords of land consolidation engineering technology have shifted from single to multiple, and the research and development fields have expanded from land preparation methods and agricultural uses to windbreak and sand fixation, soil improvement and land consolidation machinery. The keywords related to land preparation methods, agricultural uses, and weathering prevention exhibit significant continuity and an extensive time span. In the land consolidation 1.0 and 2.0 stages, far-reaching keywords like land preparation methods, agricultural uses, and preventing weathering appeared; in the land consolidation 3.0 and 4.0 stages, the research and development fields of land consolidation patents have become more diverse, especially the research and development of new materials and reagents of soil improvement and windbreak and sand fixation. The co-occurrence results of keywords in the literature on land consolidation projects show that land reclamation is the topic of most focus in the literature on land consolidation projects. Ecological restoration and ecological environment, planning and design of land consolidation projects, evaluation and models have received attention in literature research but are rarely involved in the field of patent research and development. 3) In the future, ecological land consolidation, innovative multi-source remote sensing intelligent monitoring for land consolidation, and project management of land consolidation are key areas and development directions that need to be focused on. This study can provide directions for the research and application of land consolidation engineering technologies in the future.