Community gardens offer broad research opportunities and analytical resources encompassing urban planning to environmental sustainability, food systems, and social capital. However, little is known about the knowledge structure and research development related to community gardens. This study presents an in-depth bibliometric performance analysis and visual scientific mapping analysis of the literature on community gardens by examining 487 published papers selected from the Web of Science database. The results indicated a considerable rise in research papers in this subject area from 2012 onwards, with most contributions from the United States. Studies from high-income countries accounted for 93.22%, and 38 countries have cooperated 167 times in this field. “Health” is the most frequent keyword, and the terms “ecosystem services” has been gaining popularity over the last five years. A combination of co-citation clustering and keyword co-occurrence clustering analysis identified three major research themes in the field of community gardens: “ecosystem services and disservices”, “multidimensional association”, and “sustainable garden systems”. The development of ecosystem value assessment frameworks, the establishment of region-wide soil monitoring databases, accounting for the cost-effectiveness of nature-based solutions, the integration of garden systems into smart cities, and the integration of water management into regulation will be important future research directions regarding community gardens. Overall, this study provides scholars with a systematic and quantitative understanding of community gardens.

The agro‐pastoral ecotone, an ecological transition zone connecting adjacent areas of agricultural planting area and grassland animal husbandry, has three features: a complex natural condition, relatively pronounced population pressure, and a fragile ecological environment. In this study, we conducted an ecosystem risk assessment in the western part of Jilin Province, China, based on multiscale and multitemporal remote sensing images and land‐use data. Furthermore, we focused on land‐use change from 1995 to 2015 by applying the dynamic change information survey method and carrying out a transfer track analysis. The results revealed three main findings. (1) The ecological risk index at the scale of 3 km × 3 km harbors significant spatial correlation. (2) The ecological risk index of unutilized land, forest land, and grassland is relatively high for each, and their anti‐interference ability is weak, while the ecological risk index of construction land and water area is the lowest. (3) Human interference, e.g., construction activities and cultivated land occupation, is the leading factor driving the exacerbation of ecological risk and frequent land‐use type conversions. At the study period’s end, a trend of slight contraction in the high‐risk areas was found, indicating that land‐use regulation and land protection policies have had significantly positive impact upon the lands’ ecological value. The overall study identified a reasonable research scale for eco‐environmental risk assessment and discerned relationships between regional land‐use changes through geospatial analysis. Moreover, our findings can help provide practical case study information applicable to similar regions with agro‐pastoral ecotones.

A large number of trees have been planted in built-up areas to improve the urban environment, but the effects of tree cover on spontaneous understory herbs are not yet well understood. This study surveyed spontaneous herbs in two kinds of habitats (habitats with and without tree cover) in the built-up area of the small city Junlian in Sichuan Province, China. A total of 222 species of spontaneous herbaceous plants in 180 genera of 71 families were recorded, including a vulnerable species and six species endemic to China. Although the overall species richness values were similar in the two kinds of habitat, the average species richness per quadrat of all plants, perennials, plants with the dwarf growth form, and animal-dispersed plants was significantly higher in the habitats with tree cover than in those without tree cover. The overall species association was significantly positive in the habitats with tree cover (VR = 1.51, p < 0.05) and neural (VR = 0.86) in the habitats without tree cover. Among the top 25 frequently recorded species in each kind of habitat, the species association of plants with the same trait combination type differed greatly in the two kinds of habitats. For the species association between annuals, only 13.33% of species pairs were significantly associated in the habitats with tree cover, while 22.22% of the species pairs were significantly negatively associated in the habitats without tree cover. For the species association between plants with tall growth forms, the proportion of significant positive associations in the habitats with tree cover was approximately twice than in the habitats without tree cover. For the species association between plants with the dwarf growth form, the proportion of negative associations in the habitats without tree cover was approximately twice that in the habitats with tree cover. Species with the same dispersal mode generally had a very low proportion of negative interspecific associations or a high proportion of positive interspecific associations in habitats unfavorable to their establishment. Our findings suggest that tree cover can improve the species richness of the spontaneous herbaceous species beneath them and profoundly influence interspecific coexistence relationships in a built-up area.

The relationship between urban expansion and population density changes is complex and plays a fundamental role in urban sustainable development research. This relationship has been studied in multiple large cities. However, there is no report of the relationship of the two factors mentioned above in urban agglomeration in a particular region of China. Ten cities located in the central‐southern region of Liaoning province are selected as research samples in this study. The spatial growth rate and urban compactness index of the sample cities were calculated using the land use and population data of these cities in three time phases: 1995, 2005, and 2015. Then, the geographical growth features, the population density changes, and the link between these two in the sample cities were investigated at these three periods. Our results revealed that the studied cities of central‐southern Liaoning province expanded at the three time phases under the driver of positive population density growth, but the effects of urban population change on urbanization growth modes across time were uneven across different periods. Our study showed a trend that active transition of different urbanization growth modes was associated with decreased population density.