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Rapid agricultural land expansion and urbanization have accelerated land use and land cover changes (LUCC) in the Northern Tianshan Mountain Economic Zone and have significantly impacted on the ecosystem services (ESs). However, the spatiotemporal variations of ecosystem service value (ESV) to LUCC are not well understood. Based on the land use and land cover (LULC) data from 1980 to 2019, we used a CA-Markov model to predict LUCC in 2020 and 2030, assess the spatial-temporal changes of ESV and LULC during 1980–2030, and explore the elastic response of ESV to LUCC. We found that cropland and built-up land expanded rapidly by 34.38% and 196.66%, respectively between 1980 and 2030, while grassland and unutilized land decreased significantly by 11.45% and 10.26%, respectively. The ESV of water body, cropland, grassland and forestland accounts for more than 90% of the total ESV. Our research shows that the ESV of cropland increased 32 million yuan from 1980 to 2030, mainly due to the expansion of cropland area. However, the loss caused by the reduction of grassland area was 45 million yuan. Water conservation, waste treatment, soil formation and retention, and biodiversity conservation are the primary ecosystem service function, accounting for 71.82% of the total ESV. Despite notable increases in the ESV from 1980 to 2010, grassland degradation still remains a main ecological and environmental issue from 2010 to 2030. The results suggest that effective land use policies should be developed to control the expansion of croplands and protect water body, grassland and forestland to maintain more sustainable ESs.

As one of the most serious health issues facing trees, the occurrence of decay and hollowing not only reduces the stability and quality of living trees but also leads to the deterioration of their eco-physiological functions, which creates great challenges to the conservation and sustainable management of forest resources. In recent years, the study of tree decay and hollow rot have attracted more and more attention from scholars at home and abroad. The relevant research results have a great significance for the prevention and control of affected living trees and the conservation and sustainable management of endangered species. However, there is a lack of systematic literature review and an insufficient understanding of research hotspots and trends in this field. This paper selects literature retrieved from the CNKI and Web of Science core databases as data sources, the number of publications, research topics, research status, hot spots, and trends, as well as the main research countries, institutions, and co-cited authors in the field of tree decay are visualized by using bibliometrics software CiteSpace (V.5.8.R3), and the current international research hotspots and development trends in this field were systematically summarized. The results showed that the number of papers in this field at home and abroad showed rapid growth in general, and the number of Chinese papers showed a slow growth after 2009. The number of papers published in English by Chinese authors was more than the number of papers published in Chinese in the field. From 2002 to 2021, the research hotspots in this field are constantly changing. Cluster analysis shows that the main themes of the relevant research are as follows: “Eastern Canada” tree species, “hydraulic vulnerability segmentation”, “dead wood management”, and “hydraulic safety”. The advantages and disadvantages of hollow/dead wood on forest ecosystems were explored from different perspectives, providing a theoretical basis and scientific support for the forest health and sustainable management. The United States dominates the research in this field, while China is a relatively late comer but is catching up fast, and the Chinese Academy of Sciences is the most prolific publisher on this topic in China. The influence of Chinese research in this field on relevant international publications is gradually increasing. In short, the research in this field is still in the phase of rapid development, and both the breadth and depth of quantitative research are increasing. How to accurately diagnose and quantify the internal decay of tree trunks and its relationship with tree death and forest decline under the interference and pressure of climate change and human activities is still a hot and difficult issue in this field.

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