Plant-parasitic nematodes (PPNs) are significant agricultural pests that cause substantial crop losses globally. This study investigated the abundance and distribution of PPNs concerning elevation in rice fields in Malang District, East Java, Indonesia. Nematodes were sampled across elevation gradients between 0 to over 1000 meters above sea level (masl). Pratylenchus, Aphelenchoides, and Longidorus, were found in the soil and rice roots in Malang District. Pratylenchus dominated the relative abundance of PPNs in the soil at 0-400 masl, whereas Longidorus dominated at 600 to > 1000 masl. In rice root samples, Pratylenchus sp. also dominated at 0-400 masl and Longidorus was dominated at 800-100 masl. The population density of Pratylenchus negatively correlated to elevation, pH, soil organic matter, and carbon organic. However, soil temperature positively correlated with the population density of Pratylenchus. Elevation and pH showed a negative influence on the population density of Aphelenchoides, whereas soil temperature showed a positive influence on the population density of Aphelenchoides. Soil temperature negatively correlated to the population density of Longidorus, whereas elevation and soil humidity positively influenced the population density of Longidorus. However, the population density of Longidorus increased with higher elevation and soil humidity. Understanding the specific relationships between PPN populations and environmental factors is essential for developing effective pest management strategies. Targeted approaches that consider these ecological dynamics can help mitigate crop damage and enhance rice production in varying environmental conditions, especially in the Java region.

Urban greenspaces face significant anthropogenic transformation, impacting soil ecosystems, multifunctionality, and global biodiversity. With increasing population and urbanization, understanding the drivers influencing soil nematode communities in urban greenspaces is crucial for sustainable urban ecosystem management. We chose the campus of The Ohio State University (OSU) due to its unique urban settings with minimally disturbed both turf and non-turf ecosystems. This study focuses on nematodes, the often-overlooked ecological engineers which play diverse roles in ecosystem functions. Nematodes were collected from 99 sampling locations across three soil depths to represent two ecosystem types (i.e., turf and non-turf) of the OSU campus. Among plant parasitic nematodes (PPN), Helicotylenchus and Pratylenchus populations were above damage threshold limits. No specific pattern of community composition was observed in the spatial variation map. The presence of rare PPN genera in the lower soil layers had a significant impact on beta diversity. Trophic group abundances displayed distinct patterns, with turf ecosystems exhibiting higher PPN as well as total nematode abundance decreasing with soil depths. In the subsurface layer (10-30 cm), both bacterivores and fungivores were higher in the non-turf than turf ecosystem. Fungal-dominated decomposition of organic matter was observed in both ecosystem types. Soil physiochemical properties, specifically, total organic carbon and soil texture, had a significant impact on PPN community composition. However, nematode trophic group composition was more altered by ecosystem type than edaphic factors followed by soil depths. Together these three explanatory variables explained 27.5 % of the total variance in trophic group composition. Overall, this study provides insights into the complex interactions between PPN, trophic groups, soil properties, and urban ecosystem characteristics, contributing valuable knowledge for sustainable urban greenspace management.