Amidst urbanization and industrialization in China, abandoned farmland plays a crucial role in safeguarding plant diversity within agricultural landscapes. This study aimed to examine the patterns of seasonal variation in plant diversity within abandoned farmland habitats in the Huang–Huai Plain region. Nonparametric tests were employed to analyze plant species diversity and phylogenetic diversity across seasons. Redundancy analysis and linear regression were conducted to examine the associations between plant species composition, species diversity, phylogenetic diversity, and soil environmental factors. Our results showed that plant species diversity, richness, and phylogenetic diversity were highest in spring, followed by summer, and lowest in autumn. The phylogenetic structure of plant communities demonstrated a tendency to diverge in spring, become random in summer, and cluster in autumn. Soil available potassium and soil organic matter emerged as important factors influencing plant species composition. The content of soil organic matter and ammonium nitrogen level exhibited a significantly positive correlation with the species diversity and phylogenetic diversity of plants. This study underscores the significance of considering seasonal and temporal scales when investigating plant diversity and provides a theoretical basis for biodiversity conservation in agricultural landscapes.

As urbanization and industrialization continue to advance rapidly in China, the issue of farmland abandonment is becoming more prevalent. Nevertheless, this phenomenon is crucial in protecting plant diversity in agricultural landscapes. This study sought to investigate the seasonal variation patterns of plant diversity in abandoned farmland habitats within the Huang-Huai Plain region. The plant community characteristics during spring, summer, and autumn were examined, and the variations in plant species diversity and phylogenetic diversity were analyzed across the different seasons. Spearman correlation analysis was used to explore the interrelationships among various diversity indices, and redundancy analysis and linear regression were employed to examine the connection between plant diversity indices and key soil environmental factors. The results showed that significant seasonal changes occurred in the plant community characteristics of abandoned farmland in the Huang-Huai Plain, with the number of families, genera, and species being highest in spring, followed by summer and autumn. Similarly, plant species diversity, richness index, and phylogenetic diversity were also higher in spring than in summer and autumn. The phylogenetic structure of plant communities tended to diverge in spring, be random in summer, and be clustered in autumn. The phylogenetic diversity and species diversity indexes were strongly associated, and soil organic matter and ammonium nitrogen were significantly positively correlated with plant species diversity and phylogenetic diversity. This study highlights the importance of considering seasonal and temporal scales when studying plant diversity and provides a theoretical basis for biodiversity conservation and agricultural production in the Huang-Huai Plain of China.

The large-scale spatial variation in and causes of biotic turnover of soil fauna remain poorly understood. Analyses were conducted based on published data from 14 independent sampling sites across five forest ecosystems in East Asia. Jaccard and Sørensen’s indices were used to measure turnover rates in soil fauna orders. A redundancy analysis was used to investigate multiple environmental controls of the composition of soil fauna communities. The results showed that both Jaccard’s and Sørensen’s index increased significantly with increasing latitude difference. The environment explained 54.1%, 50.6%, 57.3% and 50.9% of the total variance, and spatial factors explained 13.8%, 15.9%, 21.0% and 12.6% of the total variance in the orders’ composition regarding overall, phytophagous, predatory and saprophagous fauna, respectively. In addition, climate factors in environmental processes were observed to have a stronger effect than soil factors on the orders’ turnover rates. Our results support the hypothesis that the effect of environment factors on soil animal taxa turnover is more important than the effect of spatial factors. Climatic factors explained more variation in the turnover of phytophagic fauna, but soil and environment factors equally explained the variation in the turnover of predatory fauna. This study provides evidence to support both environmental filtering and dispersal limitation hypotheses at the regional and population scales.