Precipitation regulated soil nematode community and footprint in cropland ecosystems

Abstract

Nematode abundance and footprint show unimodal patterns with precipitation levels.• MAP governed nematode diversity along the precipitation gradient of agroecosystem.• Soil pH determined nematode abundance and footprint in low precipitation levels. Precipitation plays a crucial role in global biodiversity change across terrestrial ecosystems. Precipitation is proven to affect soil organism diversity in natural ecosystems. However, how precipitation change affects the function of the soil nematode community remains unclear in cropland ecosystems. Here, we tested soil nematode communities from different precipitation sites (300 mm to 900 mm) of the agricultural ecosystem. The abundance of total nematodes, fungivores, and plant parasites, together with the footprint of fungivores was significantly affected by mean annual precipitation (MAP) in cropland ecosystem. Plant parasites diversity and footprint showed negative relationships with MAP. The random forest suggested plant parasite footprint was the most responsive to MAP. The structural equation model revealed that MAP affected nematode abundance and footprint indirectly via soil pH; nematode diversity was affected by MAP directly. We conclude that precipitation could act as the main selection stress for nematode diversity among the large gradient of agricultural ecosystems. However, the soil pH may act as a stress factor in determining nematode community and carbon flow in the soil food web. Our study emphasized that using nematode value by trophic group would provide a deep understanding of nematode response to precipitation in cropland ecosystems.

Preliminary Study on Hourly Dynamics of a Ground-Dwelling Invertebrate Community in a Farmland Vineyard

“…Additionally, the taxonomic richness, abundance of the total ground-dwelling invertebrate community, and abundances of ants, spiders, millipedes, and grasshoppers were significantly correlated with the monitoring Day, indicating that factors occurring at a day temporal resolution may affect hourly variations. According to previous studies, various factors affect the diel variations of ground-dwelling invertebrate communities, including light intensity [86], temperature [39], precipitation [87], weather [20], food resources [6,88], farmland management [14], and vegetation [89]. Thus, we suggest that these important factors, which occur at hourly and daily temporal resolutions, should be studied further to understand the fine temporal dynamics of ground-dwelling invertebrate communities in farmlands.…”