Increasing phosphorus (P) inputs induced by anthropogenic activities have increased P availability in soils considerably, with dramatic effects on carbon (C) cycling and storage. However, the underlying mechanisms via which P drives plant and microbial regulation of soil organic C (SOC) formation and stabilization remain unclear, hampering the accurate projection of soil C sequestration under future global change scenarios. Taking the advantage of an 8‐year field experiment with increasing P addition levels in a subalpine forest on the eastern Tibetan Plateau, we explored plant C inputs, soil microbial communities, plant and microbial biomarkers, as well as SOC physical and chemical fractions. We found that continuous P addition reduced fine root biomass, but did not affect total SOC content. P addition decreased plant lignin contribution to SOC, primarily from declined vanillyl‐type phenols, which was coincided with a reduction in methoxyl/N‐alkyl C by 2.1%–5.5%. Despite a decline in lignin decomposition due to suppressed oxidase activity by P addition, the content of lignin‐derived compounds decreased because of low C input from fine roots. In contrast, P addition increased microbial (mainly fungal) necromass and its contribution to SOC due to the slower necromass decomposition under reduced N‐acquisition enzyme activity. The larger microbial necromass contribution to SOC corresponded with a 9.1%–12.4% increase in carbonyl C abundance. Moreover, P addition had no influence on the slow‐cycing mineral‐associated organic C pool, and SOC chemical stability indicated by aliphaticity and recalcitrance indices. Overall, P addition in the subalpine forest over 8 years influenced SOC composition through divergent alterations of plant‐ and microbial‐derived C contributions, but did not shape SOC physical and chemical stability. Such findings may aid in accurately forecasting SOC dynamics and their potential feedbacks to climate change with future scenarios of increasing soil P availability in Earth system models.

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The use of grass cultivation in the restoration of degraded ecosystems is widespread, in order to reveal the effect of different grass cultivation patterns on the community structure of soil mites in the integrated management area of rocky desertification. In April and July 2021, a total of 2782 soil mites belonging to 3 orders, 42 families, and 73 genera were captured from three typical grass cultivation, Lolium perenne, Dactylis glomerata and Trifolium repens, and the traditional Zea mays as a control sample, in the integrated management area of potential-light rocky desertification in the karst plateau mountains of Salaxi, Guizhou Province. The soil mite community structure was analyzed using number of taxa (genera), number of individuals, diversity index, community similarity index, MI index of predatory mites, and MGP analysis of oribatid mite ecological taxa. The results showed that: (1) The summer has a more prosperous composition and diversity of soil mites across habitats, while the dominant genera of soil mites show a differential distribution across habitats; the number of soil mite genera, individuals and individual densities was significantly higher in the three grass cultivation habitats than the Zea mays habitat, and surface aggregation of soil mites is more pronounced. (2) There were differences in soil mite community structure among the three grass cultivation patterns, with a regularity of Lolium perenne > Dactylis glomerata > Trifolium repens in the composition of soil mites genera and the number of individuals, and the proportion of shared genera was not high. (3) The diversity of soil mites varied according to the environment and season, with the highest diversity of soil mites in Lolium perenne habitats; both the community similarity analysis and the CCA analysis showed that Lolium perenne and Dactylis glomerata habitats had the highest similarity of soil mite communities (4) Predatory mites were dominated by r-selective ecotypes, and oribatida were dominated by O and P type ecotypes under the three habitat patterns. (5) Soil nutrient conditions were more favorable in Trifolium repens habitats, while soil water content was higher in Dactylis glomerata environment, and correlation analysis indicated that TK was a key environmental factor influencing soil mite community composition and diversity. Based on the above results, it is further elaborated that the artificial grass restoration model not only improves the nutrient supply of soil N, P, and K but also significantly increases the composition and diversity of soil mite species, which is beneficial to the restoration of soil mite communities and is very helpful in terms of achieving self-sustainability and restoration of soil functions in rocky desertification areas

In montane environments, as elevation increases, the combination of hydrothermal factors changing and vegetation types changing can cause changes to the soil mite community. To reveal the influence of different vertical vegetation types on the structure and diversity of soil mite communities in the Shibing Karst World Natural Heritage Property, in September 2021, specimen collection and identification of soil mites were carried out under the four typical vegetation zones of coniferous broad-leaved mixed forests (CBF), evergreen broad-leaved forests (EBF), deciduous broad-leaved forests (DBF), and river beach scrubs (RBS) in the Heritage Property. This occurred in order to analyze the community structure of soil mites. A total of 10,563 soil mites were captured in this region, belonging to 3 orders, 67 families, 137 genera; Perscheloribates and Scheloribates are the dominant groups in the area. The number of soil mite genera (CBF > EBF > DBF > RBS) and the number of individuals (RBS > DBF > CBF > EBF) differed between vegetation types. The dominant soil mite genera were not entirely consistent, with the highest values for each soil mite community diversity parameter being in the EBF habitat. The number of soil mite genera and individuals differed among vegetation types in different soil layers. It showed an apparent aggregation towards the surface layer, with complex diversity and richness indices changes. The highest community similarity indices were found between CBF and DBF, which were moderately similar. The cluster analysis results further showed that soil mite communities differed in different vegetation zones and among the same vegetation zones. The predatory gamasid mite structure is mainly r-selective. The ecological groups of oribatid mites are all O-type in the number of groups and P-type in the number of individuals. Lasiobelba, Nanhermannia, Tectocepheus, and Mochlozetes, among others, represent the group of nutrient functions that make up the soil mites in the study area. The study shows that the soil mite community of the Shibing Karst World Natural Heritage Property is rich in groups and shows gradient differences with the vegetation spectrum, and based on the unique subtropical canyon karst habitat of the Heritage Property, the community structure of soil mites will be in the process of adaptation and dynamic change, so long-term dynamic monitoring and in-depth study of the soil mites community structure of the Heritage Property are needed.

Fanjing Mountain, China, is a World Man and Biosphere Reserve, a World Natural Heritage Property, and a Nature Reserve in China. Mites communities have been reported from the Fanjing Mountain. Wetland moss microhabitats provide a unique habitat for mites, and our objective is to document moss mites communities in the subalpine wetlands of Fanjing Mountain (Jiulongchi), with a particular focus on trends in moss mites at different stages of vegetation succession in the wetlands, which have rarely been described, and the research will provide fundamental data for biodiversity conservation in the face of global climate change. The succession sequence from bryophyte (hygrophyte) to shrub (mesophyte or xerophyte) in the open area of Jiulongchi wetland successively includes Polytrichum commune Hedw. (PC), Eleocharis yokoscensis (Franch. et Sav.) Tang et-Cypers sp. (EY-C), Senecio faberii Hemsl (SF), and Indocalamus longiauritus Hand.-Mazz. (IL) four typical communities. In April 2016, we collected moss samples under the four typical communities mentioned above, and analyzed the difference of moss mite communities using PCA, Kruskal–Wallis nonparametric test, and ANOVA. The results showed the following: (1) A total of 9058 moss mites belonging to 49 genera in 3 orders and 69 families were captured in the four plant communities, with the moss mites Parachipteria, Fuscozetes, and Tectocepheus being the dominant taxa of moss mites in Jiulongchi wetland. The core taxa of moss mites at different successional stages were 12 genera, with IL having the largest number of exclusive taxa (20 genera). (2) The abundance of moss mites showed an overall increasing trend from PC to IL habitats, with the number of families and genera showing a pattern of IL > EY-C > SF > PC. The diversity index SF habitat possessed the maximum value, followed by IL, both of which were significantly different from PC. (3) The results of PCA analysis of moss mites showed that the mite community composition of PC habitats differed more from SF and IL, respectively, and less from EY-C. (4) There existed differences in the ecological taxa of predatory moss mites at different successional stages, with the Poronota group dominating the ecological taxa of oribatida. The research indicated that moss mites communities in subalpine wetlands were rich in species composition, and with the succession of vegetation from hygrophyte to mesophyte or xerophyte, the moss mites group as a whole develops in a direction favorable to its diversity, and the differences in moss mites ecological taxa also demonstrated the variability and complexity of the Jiulongchi wetland environment. This research presents the distribution pattern of moss mites in different vegetation succession stages in subtropical subalpine herbaceous wetlands. The moss mites evolution trend in response to climate-change-induced plant community succession needs further investigation.

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