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The interaction between woody plants and mycorrhizal fungi is an important biological interaction; however, the driving factors behind the diversity of mycorrhizal trees formed through the symbiosis of mycorrhizal fungi and woody plants remain unclear. In this study, we collected and compiled the woody plant data of 34 forest dynamic plots containing 3350 species from habitats around the world and divided them into AM and EcM trees. We tested the contribution of AM and EcM trees to tree diversity and its components in forest communities worldwide. Our results showed that AM trees rather than EcM trees affect the tree diversity of forest communities, and that the diversity of AM trees has a significant latitudinal gradient pattern. Climate variables, especially temperature, are strongly correlated with the diversity patterns for AM trees rather than EcM trees. Topography is the most significant factor affecting the diversity of EcM trees. Our findings highlight the importance of AM trees for the tree diversity of forest communities worldwide. Our findings have important implications for understanding the response of complex woody plant communities with different types of mycorrhizal symbiosis to climate change. [ABSTRACT FROM AUTHOR]

Soil microorganisms are a crucial component of forest ecosystems because of their involvement in the decomposition of organic matter and nutrient cycling and their influence on plant growth and development. Soil type is a fundamental characteristic of soil. In the transitional forest regions from subtropical to temperate zones in China, various soil types can be found, including yellow-brown soils, brown soils, and cinnamon soils. However, the composition and distribution patterns of soil bacterial and fungal communities in different soil types remain uncertain. This study selected a 4.8-hectare plot in Baiyun Mountain Forest National Park, China. To explore the spatial distribution and ecological processes of soil microbial communities across three different soil types, Illumina sequencing was conducted. Results showed that the composition and assembly of bacterial and fungal communities varied substantially among different soil types. Bacteria were more influenced by environmental factors than fungi. Fungal communities consistently demonstrated greater stability compared to bacterial communities across the three soil types. Light was the main environmental factor driving the variation in the assembly of microbial communities among different soil types. This study demonstrates that there are differences in the composition and structure of soil microbial communities among different soil types, providing important insights into the management and sustainable development of soil microorganisms in temperate forests. [ABSTRACT FROM AUTHOR]

Urbanization induces rapid plant environmental modifications, leading to alterations in plant diversity distribution patterns and plant homogenization. However, how plant diversity is distributed along urbanization gradients in regional urban agglomerations and its relationship with environmental factors are not well defined. In three nearby Henan Province Chinese cities—Zhengzhou, Kaifeng, and Zhongmu—along an urbanization gradient, the distribution pattern of plant diversity was quantified. Both native and non-native plants found in urban green spaces were taken into consideration. A total of 176 plant quadrats were selected and separated into three urbanization gradient types using space-constrained hierarchical clustering: urban core, urban suburb, and urban outskirt. Polynomial fitting was used to characterize the spatial distribution patterns of plants along the urbanization gradient, and Pearson correlation and the Mantel test were employed to examine the effects of environmental factors, including longitude, latitude, altitude, distance from the urban center, temperature, and illumination, on plant diversity. A total of 313 vascular plant species, comprising 137 woody species and 176 herbaceous species, were examined. Along the three urbanization gradients, remarkable variations in plant diversity for woody and herbaceous species were observed. The spatial patterns of plant diversity were consistent across cities, whereas woody plants and herbaceous plants displayed the opposite behavior. Distance to the city center and temperature were the most substantial environmental effect factors for the diversity of woody plants, whereas light factors had a major impact on herbaceous plants. These findings show different life-type plants are affected differently by urbanization, and they offer managers and planners a recommendation for increasing urban plant diversity by executing various interventions throughout the urban gradient. [ABSTRACT FROM AUTHOR]

Soil degradation of urban greening has caused soil fertility loss and soil organic carbon depletion. Organic mulches are made from natural origin materials, and represent a cost-effective and environment-friendly remediation method for urban greening. To reveal the effects of organic mulch on soil physicochemical characteristics and fertility, we selected a site that was covered with organic mulch for 6 years and a nearby lawn-covered site. The results showed that soil organic matter, total nitrogen, and available phosphorus levels were improved, especially at a depth of 0–20 cm. The activities of cellulase, invertase, and dehydrogenase in soil covered with organic mulch were 17.46%, 78.98%, and 283.19% higher than those under lawn, respectively. The marker genes of fermentation, aerobic respiration, methanogenesis, and methane oxidation were also enriched in the soil under organic mulch. Nitrogen cycling was generally repressed by the organic mulch, but the assimilatory nitrate and nitrite reduction processes were enhanced. The activity of alkaline phosphatase was 12.63% higher in the mulch-covered soil, and functional genes involved in phosphorus cycling were also enriched. This study presents a comprehensive investigation of the influence of organic mulch on soil microbes and provides a deeper insight into the recovery strategy for soil degradation following urban greening. Key points: • Long-term cover with organic mulches assists soil recovery from degradation • Soil physical and chemical properties were changed by organic mulches • Organic mulches enhanced genes involved in microbially mediated C and P cycling • Soil organic matter was derived from decomposition of organic mulch and carbon fixation • N cycling was repressed by mulches, except for assimilatory NO2− and NO3− reductions [ABSTRACT FROM AUTHOR]

Hydrogen peroxide (H2O2) is a widely used chemical, and the synthesis of this compound via two-electron oxygen reduction reaction (2e− ORR) electrochemistry has recently become a more attractive alternative to traditional anthraquinone processes, garnering increasing attention. Currently, the controlled preparation of 2e− ORR electrocatalysts is a challenge, and the in situ disinfection of H2O2 is an urgent research issue that merits further investigation. Here, BiNiOx−4 catalysts with various crystalline surfaces can be synthesized by modulating the Bi content, and applied to the electrocatalytic production of H2O2. As a result, the selectivity reached 93.2% at 0.4 VRHE under alkaline conditions. Furthermore, neither the current density nor the H2O2 selectivity decreased after continuous testing for more than 90 h, indicating the good stability of BiNiOx−4 in practical applications. In contrast, the homemade flow-cell was able to produce a H2O2 concentration of 223 mmol L−1 in 2 h under neutral conditions, surpassing the performance of other catalysts reported under similar conditions. DFT calculations demonstrated that the excellent performance of the catalyst was due to the synergistic effect of Bi and Ni in BiNiOx−4. The in situ generated H2O2 was found to achieve a complete elimination of bacteria within approximately 5 minutes. This work offers a promising outlook for 2e− ORR electrocatalytic production and in situ utilization of H2O2. [ABSTRACT FROM AUTHOR]

Electrocatalytic two-electron oxygen reduction reaction (2e− ORR) is a promising method for producing green and sustainable H2O2 but lacks high selectivity and yields electrocatalysts. And it is critical to develop catalysts that meet industrial demands. Herein, we report the different ratios of Bi0/Bi3+ supported on a phosphorus, nitrogen, and carbon nanosheet (Bi/PNC), which can reduce O2 to H2O2 with high selectivity (up to 97.75% at 0.4 VRHE) in 0.1 M KOH electrolyte and retain 97% selectivity even after 100 h electrolysis. Then a homemade flow-cell system was built for electrocatalytic production of H2O2 under an O2 atmosphere using an improved gas diffusion electrode. The Bi/PNC-4 can achieve a high H2O2 yield of 2.76 mol·gcatalyst−1·h−1 (alkaline), 5.29 mol·gcatalyst−1·h−1 (neutral), and 3.50 mol·gcatalyst−1·h−1 (acid) in universal pH conditions. The in-situ generated H2O2 can function as a degradation agent for efficiently degrading pesticides and antibiotics. The outstanding selectivity and activities are attributed to the synergistic effects of Bi0 and Bi3+ that promote proton-coupled reduction of O2 to OOH* (ΔGOOH* = 4.27 eV), and the formation of H2O2. The fast yield of H2O2 on Bi/PNC catalysts in flow-cell provides a promising path of electrocatalytic 2e− ORR for practical H2O2 production. [ABSTRACT FROM AUTHOR]

In farmland ecosystems, phosphorus and water have crucial roles. To elucidate the effects of phosphorus concentration and water management on arbuscular mycorrhizal fungi (AMF), field experiments were conducted in a farmland ecosystem (China). We examined the effects of different treatments, including drought and normal phosphorus, normal water and normal phosphorus, drought and low phosphorus, and normal water and low phosphorus, on the AM fungal biomass, diversity, and community. Results showed great differences in the AMF under different water and phosphorus concentrations. When under a suitable drought treatment, the AMF became more abundant and more conducive to plant growth. The abundance of AMF varied with different phosphorus treatments, and the abundance of AMF in low-phosphorus treatments was higher, which is more suitable for plant growth. In conclusion, as water and phosphorus concentrations change, the community structure of AMF constantly changes. Only under the appropriate water and phosphorus concentration processing can AMF play its role well. Understanding the influence of different phosphorus concentrations and the moisture contents of AMF can play a role in the agricultural production of AMF, and it can also provide improved theoretical support. [ABSTRACT FROM AUTHOR]

A serial oxygen vacancy (OV) on Nb2O5 is synthesised by H2 calcination, and H-300 exhibited high selectivity and activity for H2O2 (93.4%, 562.5 mmol gcat−1). A volcano relationship is identified between the OV content and performance, which provides an attractive insight into designing electrocatalysts. [ABSTRACT FROM AUTHOR]

A serial oxygen vacancy (O V ) on Nb 2 O 5 is synthesised by H 2 calcination, and H-300 exhibited high selectivity and activity for H 2 O 2 (93.4%, 562.5 mmol g cat -1 ). A volcano relationship is identified between the O V content and performance, which provides an attractive insight into designing electrocatalysts.