Spartina alterniflora invasion changes the function and balance of mangrove ecosystem. However, the effects of S. alterniflora invasion on soil phosphorus (P) fractions, P-cycling functional genes and their interactions are still unclear. In this study, we examined the variations of soil physical and chemical properties, P fractions, soil microorganisms and P-cycling functional genes across four different vegetation types (Kandelia obovata, Aegiceras corniculatum, Avicennia marina, Spartina alterniflora) in Zhangjiang Estuary. The results showed that: (1) The content of soil stable P was the highest, followed by moderately labile P, and the content of labile P was the least. The content of labile P in S. alterniflora soil was 91.7-143.8 mg·kg^-1, which was significantly higher than that in the three mangrove soils. The content of moderately labile P in K. obovata soil was 266.13±24.94 mg·kg^-1, which was the highest among the four vegetation types, indicating the largest supply potential of P. The content of stable P did not vary among different vegetation types. (2) S. alterniflora invasion increased α diversity and changed microbial community composition, while decreased the relative abundance of most P-cycling microorganisms. (3) P regulation and transportation genes were dominant in soil P cycling genes across the four vegetation types. The relative abundance of P regulation genes (PhoB, PhoR, PhoU) and transportation genes (PstSCAB, PhnCDE, ugpBACE) in A. marina soil was the highest, while S. alterniflora soil was the lowest. Therefore, S. alterniflora invasion led to the change of soil P cycle by changing the soil physical and chemical properties and consequently the composition of microbial community and gene expression.

This study aimed to elucidate the dynamics of mangrove litter production and the return of carbon and nitrogen, and to assess the carbon sequestration potential of different mangrove communities. Using the litter collection frame method, we monitored the monthly dynamics of litter yield and the seasonal dynamics of carbon and nitrogen storage of each component (branches, leaves, flowers, and fruits) of the invasive species Sonneratia apetala and the native species Kandelia obovata on Qi’ao Island in 2022 and 2023. We examined the impact of species identity, forest age, and tidal level on monthly variations of litter production. We further estimated the aboveground carbon and nitrogen stocks based on litter yield and carbon and nitrogen contents. These efforts are of great significance for the ecological restoration and management of mangroves in coastal cities. The results showed that the monthly total litter production varied significantly across different months, forest ages, and tidal levels (P<0.001). The mean annual total production across the four plots was 1503.1 g·m^-2, with the ranking as follows: low tide 20-year-old S. apetala > high tide 20-year-old S. apetala > K. obovata > low tide 14-year-old S. apetala. Litterfall was predominantly composed of fallen leaves (45.6%), followed by fallen fruits (35.8%), and fallen flowers being the least abundant (1.5%). A peak in litter production was observed in summer and autumn, and the average monthly temperature was significantly positively correlated with the total litter production (P<0.01). The litter carbon and nitrogen contents, as well as their storage, exhibited significant variation across different components and seasons, with the carbon and nitrogen contents ranging from 400.9 to 477.2 mg·g^-1 and 8.9 to 26.3 mg·g^-1, respectively. Sonneratia apetala demonstrated superior annual carbon and nitrogen reserves of 1096.5 g·C·m^-2 and 66.14 g·N·m^-2, respectively, which were 1.9 and 3.7 times greater than those of Kandelia obovata, underscoring its higher capacity for carbon and nitrogen return. Litter production and its carbon and nitrogen storage are influenced by multiple factors, emphasizing the necessity taking into account the effects of seasons and components for the estimation of carbon and nitrogen budgets.

The assessment of carbon storage in early recovery stage of Kandelia obovata forest is an important foundation for evaluating its function in carbon sink. In this study, we examined the biomass and carbon storage change patterns across K. obovata artificial forests with different restoration times (3, 6, and 12 years) in the Baguang area of Shenzhen. The results showed that: (1) The above and below-ground biomass of K. obovata increased from 22.74 and 8.24 kg·m^-2 (3 years recovery), to 79.33 and 23.49 kg·m^-2 (6 years recovery), and to 95.99 and 24.47 kg·m^-2 (12 years recovery), respectively. (2) There was no significant difference of total organic carbon in the same organ among different recovery times. The organic carbon content of roots (293.27-307.80 g·kg^-1) were lower than that of stems (480.26-511.83 g·kg^-1) and leaves (507.83-531.63 g·kg^-1). (3) The total organic carbon content in sediments increased from 10.85 g·kg^-1 (3 years recovery), to 15.05 g·kg^-1 (6 years recovery), and to 17.17 g·kg^-1 (12 years recovery). (4) The sediment carbon storages per unit area after 3, 6, and 12 years of recovery were 64.77, 72.40, and 81.70 Mg·hm^-2, respectively. Compared with K. obovata artificial forest with 3 years recovery, the carbon storage of plants and sediments per unit area increased with 6 and 12 years recovery, and the proportion of carbon storage in plants increased, while the proportion of carbon storage in sediment reduced. Thus, the artificial K. obovata forest in the early recovery stage has significant carbon sink function.

To understand the community characteristics and distribution patterns of meiofauna in the mangroves north of the Tropic of Cancer, we conducted investigations on meiofauna and its sedimentary environment across five habitats (Kandelia obovata, Avicennia marina, Aegiceras corniculatum, Spartina alterniflora distribution areas and naked flat) and two microhabitats (sediment and leaf litter) in the mangrove wetland of Zhangjiang estuary, Fujian Province, and analyzed the community features and influencing factors of meiofauna. A total of 11 meiofauna taxa were found in both sediment and leaf litter. Nematodes and copepods were the first and second dominant taxa, respectively. The average abundance of meiofauna in sediment was 1415.80±495.84 ind·10 cm^-2, and the average biomass was 681.38±165.61 μg·10 cm^-2. The average abundance of meiofauna on leaf litter was 5.36±6.48 ind·g^-1, and the average biomass was 4.81±5.67 μg·g^-1. There were significant differences in the abundance and biomass of meiofauna among different habitats. The abundance and biomass of meiofauna in naked flat were extremely significantly higher than those in the mangrove forest of A. corniculatum. Among the three mangrove habitats, the abundance of meiofauna in the A. marina forest was significantly higher than that in the A. corniculatum forest, while the biomass was extremely significantly higher than that in the A. corniculatum forest. The abundance and biomass of meiofauna were the highest in the surface layer of sediment, which gradually decreased with increasing sediment depth. Meiofauna had highest abundance and biomass on leaf litter with highest decay levels. The community structures of meiofauna were significantly different among the five habitats and the two microhabitats. There were significant differences between naked flat and the other four habitats with vegetation. The abundance and biomass of meiofauna in sediment were significantly positively correlated with sand content and significantly negatively correlated with median grain size. The abundance and biomass of meiofauna on leaf litter were extremely significantly negatively correlated with hydrolyzed tannin content and organic carbon content. The combination of sand content and organic carbon content could best explain the community structure of meiofauna in sediment. The combination of median grain size and organic carbon content could best explain the community structure of meiofauna on leaf litter. Our results indicate that the heterogeneity of habitats and microhabitats has a significant impact on the spatial distribution of meiofauna in the Zhangjiang estuary mangrove wetland. Vegetation types (including the presence or absence of vegetation), sediment grain size, and food resources in habitats were the main environmental factors affecting the spatial distribution of meiofauna.

The climate-change-induced northward shift of mangroves in China has widely been recognized. However, its impacts on the dynamics of soil organic carbon (SOC) stock and underlying mechanisms remain poorly understood. Using a space-for-time substitution approach, we investigated the temporal dynamics of SOC content and density (SOCD), as well as their vertical distribution patterns, during the development of northward mangroves in southern Zhejiang. We further compared our results with that in 30-year-old mangrove stands in Fuding, Fujian Province. Results showed that the SOC content and SOCD of the northward-afforested mangroves generally increased with stand age. In 15 a mangroves, SOC exhibited a pronounced decreasing trend with increasing soil depth, and both SOC content and SOCD in the surface layer(0-20 cm) were significantly higher than those of other stand ages. Average SOC content (0.91%±0.18%) and SOCD (103.58±7.06 t C·hm^-2) of the 15-year-old northward mangroves were significantly higher than the 2- and 5-year-old mangroves, but were not different from the 30-year-old mangroves in Fuding (P>0.05). The accumulation of SOC and SOCD was mainly driven by pH and nitrogen content, and also driven by multiple environmental factors such as clay content and salinity during mangrove restoration in southern Zhejiang. These results suggest that the conservation and restoration of northward-afforested mangroves in southern Zhejiang can enhance coastal wetland organic carbon storage within a relatively short term, contributing to carbon sequestration and climate change mitigation.

Mangrove forests are among the most productive coastal “blue carbon” ecosystems, and thus assessing and enhancing their carbon sequestration service value is crucial for addressing global climate change. Despite the growing activities in global blue carbon trading, the valuation of mangroves remains highly uncertain and is often underestimated. Taking the Gaoqiao mangrove forest in Zhanjiang as a case, we employed seven distinct methods to calculate its carbon sequestration service value and developed an assessment framework based on carbon enhancement strategies. Results showed that Rhizophora stylosa, Avicennia marina, Aegiceras corniculatum, and Bruguiera gymnorrhiza exhibited unit area carbon sequestration service value ratios of 1.59∶1∶1.18∶1.32, with R. stylosa and B. gymnorrhiza demonstrating the highest carbon sequestration value capacity. The total estimated value of mangrove carbon sequestration services ranged from 4.70 million to 61.90 million CNY. Methods such as the market price approach yielded conservatively low estimates by failing to account for the multifunctional ecological benefits, leading to a significant underestimation of their comprehensive value. Among the methods, Marginal Abatement Cost (MAC) and Carbon Capture and Storage (CCS) are most suitable for assessing carbon storage value, while the Social Cost of Carbon (SCC) and carbon tax methods are more appropriate for assessing carbon fixation value. Based on the dynamic assessment framework developed here, it is estimated that implementing moderate to high intensity management strategies could enhance the carbon sequestration service value of mangroves in the study area by 20% to 30% relative to the current baseline. Furthermore, our results clarified the applicable contexts of different valuation methods and revealed the significant carbon sequestration value and potential of mangrove ecosystems, thereby providing strong support for their scientific quantification and the formulation of comprehensive ecological conservation strategies.

Mangrove ecosystems which distribute in intertidal zone have important ecological functions. Under the background of sea level rise, the survival of mangroves, especially endangered ones, is threatened by flooding stress. It is of great significance to understand the effects of flooding stress on mangroves. Flooding stress mainly affects the growth of mangroves, and further inhibits their physiology by affecting photosynthesis, stress-resistant enzyme activity, molecular regulation mechanisms, and root system. Although the effects of flooding stress on the physiological ecology of mangroves have been studied considerably, there are limitations in species identities and growth stages. Dynamic tidal simulation technology is the support of experimental design to study the physiological and ecological effects of flooding stress on mangroves. In the future, we should break through the bottleneck of dynamic tidal simulation technology and conduct more in-depth research combining ecosystem ecology, transcriptomics and metabolomics, to provide a basis for scientific understanding of mangroves’ response to global change and ecosystem management.

Phosphorus is one of the key nutrients that limit plant productivity. In deserts, phosphorus is particularly crucial given its deficiency in soil. Groundwater is one of the significant factors affecting soil phosphorus content in deserts. However, the variations of soil phosphorus fractions at different groundwater depths remain poorly understood. In this study, changes in soil phosphorus fractions at three groundwater depths (2.5, 4.5, and 11.0 m) were characterized using the Hedley phosphorus classification method. The results showed that the concentrations of active phosphorus (sodium bicarbonate-extractable inorganic phosphorus, sodium bicarbonate-extractable organic phosphorus), insoluble phosphorus (diluted hydrochloric acid-extractable phosphorus, concentrated hydrochloric acid-extractable inorganic phosphorus, concentrated hydrochloric acid-extractable organic phosphorus, residual phosphorus), and sodium hydroxide-extractable inorganic phosphorus at the groundwater depth of 11.0 m were significantly greater than those at the groundwater depths of 2.5 m and 4.5 m. However, sodium hydroxide organic phosphorus and resin phosphorus showed no variation. Soil microbial biomass phosphorus at 2.5 m depth was significantly lower than those at 4.5 and 11.0 m, microbial biomass carbon was significantly lower at 4.5 m compared to 11.0 m, and microbial biomass nitrogen  did not vary among the depths (P<0.05). Redundancy analysis revealed that groundwater depth was a key environmental factor influencing the variations in soil phosphorus fractions. This study provides a scientific basis for understanding the response of soil phosphorus fractions in deserts to varying groundwater depths and offers a theoretical foundation for the recovery and conservation of desert plants.

The effect of land use change on terrestrial ecosystem carbon pools is a hot topic in current global climate change research. Most of previous studies have focused on the estimation of soil organic carbon pools at the regional scale, but overlooked the response of soil organic carbon (SOC) components to land use change in subtropical mountainous areas and their underlying mechanisms. We explored the effects of land use types on the contents of SOC components across three typical forests in the Dongjiang Lake Basin, namely subtropical secondary forests, plantation forests and economic forests. Results showed that land use type did not affect total SOC, C∶N ratio and mineralassociated organic carbon (MAOC), but significantly affected particulate organic carbon (POC). In the 10-30 cm layer, POC content of economic forests was 37% and 41% lower than plantation forests and secondary forests, respectively. The lower POC in economic forests were associated with lower aboveground biomass. Our results demonstrated that converting economic forests into secondary forests or plantation forests may reduce the risk of soil organic carbon loss and is beneficial for enhancing the carbon sink function of mountainous soil and the carbon sequestration potential of regional forests in the Dongjiang River Basin. These findings enhance our mechanistic understanding of carbon sequestration in forest soil, and provide data support for optimizing regional land management models and improving the carbon sequestration potential of forest ecosystems.

To reveal the main factors limiting the growth of Salix psammophila and provide a scientific basis for the sustainable and efficient development of the Three-North Shelter Forest, we examined the variations of the C, N, P, and K contents and stoichiometric ratios in leaf and new branch under non-stubble, single-row interlaced stubble and full stubble treatments in the declining S. psammophila plantations on alpine sandy land of Gonghe Basin, Qinghai Province, and analyzed their relationships with soil nutrients. The results showed that the C, N, P and K contents in leaf and branch of two stubble plantations were significantly higher than non-stubble plantation (P<0.05). Leaf C∶N in singlerow interlaced stubble plantation was significantly higher than that of other plantations (P<0.05), while the C assimilation capacity and N use efficiency were improved. Compared with nonstubble plantation, the C∶P and C∶K in leaf and new branch of the two stubble plantations were significantly decreased, indicating that the stubble measures enhanced the P and K uptake capacity of S. psammophila. For non-stubble, single-row interlaced stubble and full stubble plantations, leaf N∶P was 19.11, 15.07 and 15.94, leaf N∶K was 1.18, 0.74 and 0.86, and leaf P∶K was 0.06, 0.05 and 0.05, respectively, which indicated that the growth of non-stubble plantation was limited by P, and the growth of two stubble plantations were co-limited by N and P. Soil available phosphorus (AP) content increased in stubble plantations. The soil AP content was the main influencing factor of the C, N, P and K contents and their stoichiometric ratios in leaf and branch, with the explanatory degree of 71% and 50%, respectively. In conclusion, the growth of S. psammophila plantations in this region is mainly limited by P element. P fertilizer should be applied appropriately in plantation management. Single-row interlaced stubble measure should be adopted for the restoration of the declining S. psammophila plantations, and P and N fertilizers should be applied simultaneously.

We examined species composition, growth forms and synusia composition of the ground-dwelling bryophytes, as well as the relationship between the distribution of associations and environmental factors, in an artificial Pinus sylvestris var. mongolica forest in the southeastern region of the Hunshandake Sandy Land, through the construction of growth form system based on the morphology of individuals, cluster and ordination analysis of 16 forest plots. The results showed that there were 41 bryophyte species belonging to 25 genera and 14 families, which contained nine types of growth forms, mainly including small acrocarpous mosses (ten species), medium acrocarpous mosses (nine species), small pleurocarpous mosses (eight species) and large pleurocarpous mosses (six species). The two-way indicator species analysis (TWISPAN) revealed that the 16 plots could be divided into six groups, which contained 2-27 species, 1-9 growth forms, 1-4 synusia. The dominant synusia were small acrocarpous mosses, medium thallus liverworts, small pleurocarpous mosses (two groups), and large pleurocarpous mosses (two groups). The bryophyte associations were named after the dominant species in each synusia. Results from the canonical correspondence analysis (CCA) showed that annual average temperature, altitude, air humidity, soil moisture, light intensity, herbal coverage, annual average precipitation, tree coverage, and litter coverage were the factors affecting the distribution of ground-dwelling bryophyte associations in the artificial Pinus sylvestris var. mongolica forest in the Hunshandake Sandy Land.

Plant functional traits affect plant growth and resource utilization strategies. Clarifying the changes in plant functional traits and their relationship with carbon storage during community succession under forest management is crucial for the accurate enhancement of forest quality and carbon sequestration. We analyzed the variation in community-level leaf and fine root functional traits of Cunninghamia lanceolata forests with different sprouting densities (high, moderate and low) at the early stage of succession in Baishanzu National Park. The relationship between these functional traits and above and belowground carbon density was evaluated. The results showed that: (1) With reduced C. lanceolata sprout density, the community-level leaf carbon content and leaf C/N ratio decreased, indicating a shift in the aboveground resource use strategy from conservative to acquisitive strategy. (2) The community-level root length density, root carbon and nitrogen contents decreased with decreasing sprout density, but the root C/N ratio increased, suggesting a shift in the belowground strategy from acquisitive to conservative. Moreover, the correlation between leaf and root traits was weak. (3) The aboveground, belowground, and total carbon density were significantly affected by leaf traits (explaining 48.9%, 84.6% and 72.0% of the variances, respectively). These findings are of great significance for regulating stand structure, optimizing tree species composition, and improving carbon sink function during plantation succession.

The karst faulted basin is among the areas most severely affected by rocky desertification. To understand root response characteristics and adaptation strategies of dominant shrub species to rocky desertification in karst faulted basins, we selected Dodonaea viscosa, Osyris wightiana, and Osteomeles schwerinae with relatively similar growing status across different degrees of rocky desertification (none, potential, mild, moderate, and severe) in Jianshui County, Yunnan Province. By excavating soil profiles to obtain root and performing root scanning, we analyzed changes in root functional traits of these dominant shrubs. The specific root length, root tissue density, and specific root area of Dodonaea viscosa increased with the intensification of rocky desertification. Root tissue density, specific root length, specific root area, and branching intensity of Osyris wightiana increased initially and then decreased from none to moderate rocky desertification, and then significantly increased and reached their maximum values in severe rocky desertification, respectively increasing by 2.6, 2.8, 15.0, and 0.3 times compared to the moderate rocky desertification (P<0.05). Root tissue density, root area density, and root length density of Osteomeles schwerinae decreased with the increasing degree of rocky desertification, while branching intensity significantly increased in moderate and severe rocky desertification, with respective increases of 121.2% and 117.6% compared to the non-rocky desertification (P<0.01). Root tissue density, specific root length, and specific root area of Osyris wightiana were significantly higher in severe rocky desertification than Dodonaea viscosa and Osteomeles schwerinae (P<0.05). Root tissue density, specific root length, and specific root area of dominant shrub species were significantly positively correlated with soil available potassium concentration (P<0.01), while root area density and root length density were significantly positively correlated with plant height and aboveground biomass (P<0.05). Those results suggested that the roots of dominant shrub species exhibited a certain level of responsiveness and different adaptation strategies to varying degrees of rocky desertification. Soil available potassium content was one of the main factors influencing their adaptation to rocky desertification, while the aboveground parts played a role in regulating root traits. The results can provide a theoretical basis for optimizing vegetation restoration methods for rocky desertification in karst faulted basins.

To provide support for accurately measuring the carbon sink of garden plants, we investigated the impact of different maintenance methods on the carbon budget of Hydrangea macrophylla ‘Hanatemari’, and explored carbon sequestration and emission reduction potential of three substrate types (S1: garden soil; S2: 50% garden soil + 50% garden waste; S3: 50% garden soil + 40% garden waste + 10% biochar) and two irrigation methods (FI: full irrigation; DI: deficit irrigation) in urban landscaping applications. The results showed that under DI conditions, the S3 substrate significantly promoted leaf dry weight, root dry weight, and total biomass of H. macrophylla (P<0.05), allowing the maintenance of the highest total biomass (68.12 g·plant^-1) and total plant carbon storage (29.38 g·plant-1) with low water consumption. Among all links in the maintenance management of H. macrophylla, carbon emissions followed an order of irrigation > pruning > pest and disease control > fertilization. There were significant differences in carbon budget values under different management methods. Compared to FI, DI increased carbon budget by 92.88%, with the highest value under DI conditions observed in the S3 substrate (-21.18 g·plant^-1). Compared with S1 substrate, the organic carbon storage of S2 and S3 substrates increased by 19.94 times and 15.56 times, respectively. Specifically, compared with traditional burning, the S2 substrate reduced greenhouse gas emissions by 55%, while the S3 substrate reduced CO₂e emissions by 2.35 times and sequestered 1.52 kg CO₂e. Among the examined management practices, the combined use of deficit irrigation and biochar (DI+S3) was the most suitable management combination for improving carbon sink of H. macrophylla and the soil carbon sequestration and emission reduction capacity.

Enhalus acoroides is the dominant seagrass species in Xincun Bay and Li’an Harbor, Lingshui, Hainan, but has shown an obvious declining trend in recent years. From 2021 to 2022, we conducted investigations on the E. acoroides seagrass beds for six times in Xincun Bay and Li’an Harbor. We measured the morphological and physiological variables of E. acoroides, and analyzed the effects of environmental factors on those variables. The results showed that seawater temperature, pH, ammonium, DIN, phosphate, seagrass leaf length, belowground issue C/N ratio were significantly higher in Xincun Bay than in Li’an Port, while seawater salinity, nitrate concentration, leaf width and N content of belowground tissues were significantly lower in Xincun Bay than in Li’an Port. E. acoroides in Xincun Bay was mainly affected by seawater salinity, pH, and sediment grain size. Leaf length was positively correlated with seawater salinity, pH, and sediment grain size. Aboveground, belowground, and total biomass were positively correlated with sediment grain size and seawater salinity. In Li’an Port, E. acoroides was greatly affected by seawater salinity, pH, nitrate, phosphate, and sediment organic carbon. The aboveground, belowground, and total biomass were significantly negatively correlated with the sediment organic carbon and seawater ammonium, and positively correlated with seawater pH and nitrate. Compared with historical data, the nitrogen content in seagrass tissues significantly increased (>2.45%). In the future, the discharge of aquaculture sewage into the seagrass beds in Xincun Bay and Li’an Port should be strictly controlled. Special funds should be set up for long-term monitoring of the health status of seagrass beds, and research on the degradation mechanism of damaged seagrass beds should be strengthened. This study can provide a scientific basis for understanding the synergistic effects of seawater temperature, salinity, and nutrients on E. acoroides.

To elucidate the relationship between the population size of dominant thrips species on different host plants and altitude, we examined the altitudinal distribution patterns of dominant thrips at elevations ranging from 1800 to 3200 m in the Dashanbao Nature Reserve, Zhaotong City, Yunnan Province. Regression analysis, correlation analysis, and significance testing were applied to explore the effects of altitude and host plants on the distribution patterns of dominant thrips species. The results showed that the dominant thrips populations were mainly composed of Frankliniella occidentalis (an invasive species) and Haplothrips chinensis (a native species). The population size of F. occidentalis on Trifolium repens (r=-0.889, P<0.001), Aster oliganthus (r=-0.822, P=0.001), and Buddleja davidii (r=-0.487, P=0.065) decreased, whereas population size of F. occidentalis on Anaphalis margaritacea (r=0.533, P=0.032) significantly increased with increasing altitude. The population of H. chinensis declined with increasing altitude on T. repens (r=-0.770, P<0.001), increased on B. davidii (r=0.123, P=0.661) and A. margaritacea (r=0.419, P=0.005), and was not observed on A. oliganthus. The population of F. occidentalis at 3200 m showed no significant difference compared to those at 1800, 2150, and 2500 m, while significant differences were observed among all other altitude pairs (P<0.05). For H. chinensis, the highest abundance occurred at 1800 m; the population at an altitude of 2500 m was also significantly higher than that at 2150 m (P<0.05), with no significant differences among other altitudes. F. occidentalis and H. chinensis were the dominant thrips species in Dashanbao Nature Reserve, with F. occidentalis being more abundant than H. chinensis. Across the altitudinal gradient from 1800 m to 3200 m, the invasive species F. occidentalis exhibited a continuous decline in population with increasing elevation, whereas the native species H. chinensis showed a tendency to aggregate toward higher altitudes, with relatively higher abundance in these regions.

Exploring the effects of reducing nitrogen application combined with different active organic materials on the allocation patterns and stoichiometry of carbon (C), nitrogen (N), and phosphorus (P) in various rice organs can provide a theoretical basis for the efficient nutrient management of highquality rice production in Qianxi, Guizhou Province. An experiment with five treatments was set up, including conventional fertilization (F), 20% nitrogen reduction (CF), 20% nitrogen reduction combined with commercial organic fertilizer (OM), 20% nitrogen reduction combined with biochar (B), and 20% nitrogen reduction combined with both commercial organic fertilizer and biochar (BOM). We examined the effects of different fertilization treatments on the yield, quality, and C∶N∶P stoichiometry of rice. The results showed that compared with F treatment, the grain and straw yields of OM, B, and BOM treatments increased by 9.7%-24.6% and 3.6%-13.0%. Rice yield was the highest in BOM treatment. Plant height, effective spike number, and 1000grain weight of BOM treatment were the highest, which were 98.43 cm, 25.42 spikes and 31.43 g, respectively. Compared with CF treatment, the protein, total starch, and reducing sugar contents of BOM treatment were increased by 11.4%, 4.7% and 25.0%, respectively, while the amylose content decreased by 8.2%. In terms of nutrient uptake and utilization efficiency, the accumulation of N, P, and K in BOM treatment increased by 39.8%, 32.9% and 33.8%, respectively, and the partial factor productivity of nitrogen fertilizer and nitrogen uptake efficiency increased by 54.0% and 74.8%, respectively. Compared with F treatment, C∶N and C∶P in each part of the rice plants were significantly decreased in OM, B, and BOM treatments, while N∶P was significantly increased in grain and straw. The grain and straw yield, protein content, the partial factor productivity of nitrogen fertilizer, and nitrogen uptake efficiency were significantly positively correlated with the N∶P ratio of rice grains. Under nitrogen reduction conditions, the combined application of organic materials with varying carbon stability effectively regulates the stoichiometric balance of C∶N∶P in rice, enhances nitrogen uptake and use efficiency, and ultimately improves rice yield and quality.

To explore the effect of Chinese milk vetch (Astragalus sinicus L.) as green manure on the abundance of denitrifying functional genes in paddy soils and their driving factors, we employed real-time quantitative PCR to assess the abundances of nirS, nirK, nosZ Ⅰ, and nosZ Ⅱ genes, along with soil physicochemical properties and potential N₂O emissions. The field trial had eight treatments followed a randomized block design, incorporating three factors: planting green manure, straw return, and chemical nitrogen reduction. Results showed that planting green manure significantly increased soil ammonium content while decreasing soil pH. Neither straw return nor chemical nitrogen reduction had significant effects on the abundance of any denitrifying functional genes. Planting green manure did not affect the abundance of nirS, nirK and nosZ Ⅰ genes, but reduced the abundance of nosZ Ⅱ genes (P<0.01) by 26.6%. The abundance of nirS gene was significantly higher than that of nirK and the abundance of nosZ Ⅰ gene was significantly higher than that of nosZ Ⅱ, indicating that nirS and nosZ Ⅰ were the dominant nitrite-reducing and nitrous oxide-reducing bacteria in paddy soils, respectively. Random forest and correlation analyses revealed that nosZ Ⅱ gene abundance was significantly negatively correlated with soil ammonium content (P<0.001) and positively correlated with soil pH (P<0.01). Moreover, planting green manure significantly increased potential N₂O emissions, while straw return and chemical nitrogen reduction did not affect emissions. Overall, planting green manure increased soil ammonium nitrogen supply, potentially allowing for reduced chemical nitrogen fertilizer application. However, the reduction in nosZ Ⅱ abundance and the increase in potential N₂O emissions due to planting green manure warrant special attention.

We explored the effects of straw returning to the field and different rare earth stresses on soil core microbial communities and their functions, by adding 0, 500 and 1000 mg·kg^-1 of La of light rare earth element (REE), Gd of medium REE, and Y of heavy REE; 1% and 2% rice straw to the corresponding PVC barrels respectively (each barrel contained 1000 g of soil). Results showed that different types and contents of REEs and different proportions of rice straw, affected the relative abundance, indicative species and core species of bacteria. Rare earth content had the greatest impact, followed by rare earth type and straw incorporation proportion. The core microbial community was determined based on the relative abundance and related functions of bacteria. The core microbial phyla of the samples added with 1% and 2% rice straw and 0 mg·kg^-1 and 500 mg·kg^-1 La, Gd, and Y were Firmicutes, Proteobacteria, Actinobacteriota, Acidobacteriota, Bacteroidota and Chloroflexi, and the core bacterial genera were Anaerolina, Oxobacter, Bacillus, Candidatus Koribacter, Clostridium sensu stricto 8, Ruminiclostridium, Candidatus Solibacter, Pseudobacteroides, Novosphingobium, Ammoniphilus, Alicyclobacillus, Cellulomonas, and Bradyrhizobium. The core phyla of samples added with 1% and 2% rice straw, 1000 mg·kg^-1 La and Gd were Firmicutes, Proteobacteria, Bacteroidota, and Actinobacteriota. The core bacterial genera were Bacillus, Cellulomonas, Geodermatophilus, and  unclassified_f_Acetobacteraceae.  The core bacterial phyla of the samples added with 1% and 2% rice straw and 1000 mg·kg^-1 Y were Firmicutes and Actinobacterota, and the core bacterial genera were Bacillus and Alicyclobacillus. The samples added with 1000 mg·kg^-1 Y and 1% and 2% rice straw showed the most significant difference in bacterial function compared to other samples, followed by samples added with 1000 mg·kg^-1 La and Gd. Compared to other samples, the soil bacteria added with Gd showed significantly lower functions in human diseases, metabolism, cellular processes, environmental information processing, and biological systems. The bacterial disease pathways of samples added with 1000 mg·kg^-1 Y and 1% and 2% rice straw were significantly smaller than those of other samples. The heavy REE in the soil reaching 1000 mg·kg^-1 has a significant impact on the core microbial community, while 2% of straw returning to the field can reduce the stress of rare earths on the environment.

The extensive use of plastics has led to the widespread presence of microplastics (MPs) in agricultural soils, which are emerging pollutants with a significant impact on crop growth and development. This study aims to analyze the effects of different concentrations and types of MPs on the growth of maize seedlings. There were two types of MPs with a particle size of 0.15 mm, polyethylene (PE) and polyvinyl chloride (PVC), and three exposure concentrations \[0 (CK), 0.5%, and 5%\]. Height, leaf area, leaf SPAD value, dry matter accumulation, and root morphology of maize seedling under different MPs treatments were analyzed. The results showed that the growth of maize seedlings was mainly influenced by MPs concentration instead of MPs type. Compared with that in the CK, plant height, leaf area, aboveground biomass, and root biomass showed an increasing trend under 5% MPs treatment, but a decreasing trend under 0.5% MPs treatment. Compared with that in the CK, plant height, leaf area, and SPAD value were significantly reduced under 0.5% PVC MPs treatment (P<0.05). Conversely, leaf and aboveground biomass were significantly increased under 5% PE MPs treatment (P<0.05), and leaf, stem, aboveground biomass, and belowground biomass were significantly increased under 5% PVC MPs treatment (P<0.05). The 5% MPs treatment significantly increased root length, root volume, and root surface area by 55.1%-162.5%, 53.3%-86.9%, and 106.8%-127.7%, respectively, while 0.5% MPs had no significant effect on root variables. Overall, a 5% concentration of MPs enhanced the plant health index of maize seedlings, with no significant differences in various growth indicators between PVC and PE under the same concentration of MPs. Principal component analysis revealed that the traits of maize seedlings treated with 5% PE-MPs and 5% PVC-MPs were mainly driven by aboveground biomass, leaf dry weight, total biomass, root surface area, and root volume, while the traits of maize seedlings treated with 0.5% PE-MPs and 0.5% PVC-MPs were driven by root/shoot ratio. In summary, the concentration of MPs, rather than their type, significantly affects the growth of maize seedlings, exhibiting a general trend of “inhibition under low concentration and promotion under high concentration”.

To examine the effects of planting density and nitrogen application level on root tiller development and yield formation in extremely-late sowing wheat, a field experiment was conducted from November 2022 to June 2024 at the Hongbu National Experimental Base of the Wheat Research Institute, Shanxi Agricultural University. Using Jimai 22 as the test material, a split-plot design was employed, with the main plot representing three planting densities: 525×10⁴ plants·hm^-2 (D1), 600×10⁴ plants·hm^-2 (D2), and 675×10⁴ plants·hm^-2 (D3). Nitrogen fertilization regimes were applied as subplots, with base fertilizer, green manure, and jointing fertilizer applied at three different ratios: 5∶2∶3 (N1), 5∶4∶1 (N2), and 3∶4∶3 (N3). The effects of planting density and nitrogen application interaction on the number of secondary roots per plant, tiller number, leaf area index, aboveground dry weight, yield and yield components in extremely-late sowing wheat were examined. The results showed that at the same density, both the number of secondary roots per plant and leaf area index during the grain filling stage were highest in N3. The number of tillers was N3>N1>N2 in the D1 and D3 treatments and N3>N2>N1 in the D2 treatment during the 2022-2023 period. In the 2023-2024 period, the annual average followed the order N3>N2>N1. The aboveground dry weight of D2 and D3 treatments was N3>N2>N1. The yield exhibited patterns of N3>N1>N2 in 2022-2023 and N3>N2>N1 in 2023-2024, with the highest yield under the nitrogen fertilizer ratio of 3∶4∶3. During the grain filling stage, under the same nitrogen fertilizer ratio, the numbers of secondary roots, tillers, leaf area index, and aboveground dry weight per plant were the highest in the D3 treatment. Yield decreased and then increased with increasing density in both years, the highest yield was achieved at a density of 675×10⁴ plants per hectare and a nitrogen fertilizer ratio of 3∶4∶3. Among them, the yield increased by 2.76% to 17.79% in 2022-2023 compared with the other treatments, and by 8.24% to 31.86% in 2023-2024. Correlation analysis indicated that yield was significantly positively correlated with the number of stem tillers and leaf area index at the filling stage, with the number of panicles at the mature stage, and with the dry weight of the aboveground part, with a correlation coefficient of 0.91. Principal component analysis indicated that the overall score was highest when the sowing density was 675×10⁴ plants·hm^-2 and the nitrogen fertilizer ratio was 3∶4∶3. In conclusion, moderate density (675×10⁴ plants·hm^-2) and optimal nitrogen fertilizer management (nitrogen fertilizer ratio of 3∶4∶3) can increase the number of secondary roots, tillers per plant, leaf area index, aboveground dry weight, and yield. This combination can serve as an effective nitrogen management strategy for high-yield of efficient extremely-late sowing wheat cultivation in the southern Shanxi region.

To screen suitable habitat compensation tributaries for indigenous fish in the main stream affected by habitat changes in the reservoir area after the completion of a planned power station in the upper reaches of the Yellow River, we conducted habitat quality assessments and fish resource surveys on the main and tributary streams of the Yellow River in June and September 2023. Using remote sensing, the main and tributary rivers of the Yellow River in the study area were divided into 213 sections, which were then clustered and grouped based on environmental variables. Representative river sections were selected from each group for plot survey. Referring to the qualitative habitat evaluation index (QHEI), the weighted average model was used to calculate the overall quality assessment score of each tributary. The results showed that the scores of Qiemuqu and Gequ were 72.7 and 70.9, respectively, indicating good habitat quality level. The scores of other tributaries were all <70, indicating average or poor quality level. Based on the rating results, Qiemuqu and Gequ were selected as alternative rivers for habitat compensation. A comparative analysis was further conducted on the suitability of Qiemu〖HJ*4〗qu, Gequ, and the Yellow River main stream above Longyangxia, as well as Bagou River, Daheba River, and Qushen’an River with good habitats. The results showed that the fish commonality between Gequ and Qiemuqu accounted was 58.82%, which was not inferior to other rivers. In terms of fish diversity, the Shannon diversity index and Margalef richness index of each river ranged from 0.781 to 2.959 and 2.001 to 2.790, respectively. For those two variables, the values of Qiemuqu were 2.324 and 2.215, and the values of Gequ were 2.959 and 2.138. Ultimately, we determined that Qiemuqu and Gequ would be the habitat compensation rivers after the water storage in the planned power station reservoir area. Our results provide a scientific basis for the protection of the habitats of endemic fish species under the influence of hydropower development in the reservoir area of this power station.

Antarctic krill (Euphausia superba) and ice krill (Euphausia crystallorophias) are key species in the Ross Sea. However, studies on the distribution and niche overlap of these two species in this region are rather limited. Given their ecological importance and the potential effects posed by ongoing climate change, we investigated the summer habitat distribution and ecological niches of these two krill species. Based on occurrence records and environmental data including chlorophyll a concentration, sea surface temperature, salinity and sea ice thickness, an ensemble model integrating four algorithms was used to analyze the summer habitats and niches of two krill species in the Ross Sea. The results showed that the two krill species had significant spatial overlap in Terra Nova Bay. However, the habitat range of Antarctic krill was broader, extending to the shelf break in the northwestern side of the Ross Sea. Moreover, the ecological niche ellipsoid of Antarctic krill fully encompassed that of ice krill, indicating the higher environmental tolerance and adaptability of Antarctic krill. By revealing the spatial distribution and niche characteristics of Antarctic krill and ice krill, our results provide scientific support for ecosystem conservation and the development of research and monitoring programs for the Ross Sea Marine Protected Area.

To investigate the characteristics of macrobenthic feeding functional groups and their relationship with environmental factors in the Spartina alterniflora wetland of southern Zhejiang, a comprehensive survey was conducted in July and August 2020 in four sites with extensive S. alterniflora cover: Sanmen Bay, Yueqing Bay, Oujiang Estuary, and Feiyun River Estuary. The survey examined wetland vegetation, macrobenthos, water quality, and sediment characteristics. A total 59 species of macrobenthos were identified, classified into five feeding functional groups: carnivore (CA), detritivore (DE), omnivore (OM), herbivore (HE), and planktivore (PL), comprising 20, 13, 11, 8, and 7 species, respectively. Among these feeding groups, DE and PL were dominated, collectively accounting for 70% of relative abundance, followed by CA and HE, with a total relative abundance of 26%. OM was the least abundant, accounting for only 4%. Notably, only three feeding functional groups were present in the Feiyun River Estuary, whereas all five groups were recorded in the other three sites. Cluster analysis revealed significant differences between the Feiyun River Estuary and the other three regions. Redundancy analysis showed that environmental factors such as S. alterniflora height, interstitial water, and sediment properties played crucial roles in shaping the distribution of feeding functional groups. Among all these factors, total salt content of sediment was the most important one. S. alterniflora facilitated the expansion and survival of Phascolosoma arcuatum, highlighting its ecological influence on microbenthic communities.

Bactrocera cucurbitae and B. tau are sibling species. They often occur in mixed populations in the field and are difficult to control. To clarify the oviposition patterns of those two species, we cultured them in artificial climate chambers. We measured oviposition status and oviposition duration, and analyzed the correlation between age and fecundity. The results showed that the average adult longevity and oviposition period of B. cucurbitae adults were 78.83 and 61.47 days, respectively, being shorter than those of B. tau (94.77 and 75.33 days). The average number of eggs laid per female per day and the average number of egg clutches per female per day were 10.64 and 8.83 for B. tau, which were higher than those of B. cucurbitae (6.57 and 6.56, respectively). The total oviposition period of B. tau was 4 days longer than that of B. cucurbitae, and its cumulative average fecundity reached 625.87 eggs, approximately 200 more than B. cucurbitae (431.41 eggs). These findings suggest that B. tau exhibits a stronger oviposition competitiveness under indoor conditions. Therefore, in field management, effective control measures should be implemented before oviposition, with differentiated strategies for species-specific outbreaks. Priority should be given to targeting the more harmful species, while the other should be managed accordingly.

Given the potential impact of selenium (Se) on human health and ecosystems, as well as its significance in the study of lepidocrocite transformation mechanisms, we explored the role of hydrated ferrous ions (Fe(Ⅱ)(aq)) in mediating the abiotic catalytic transformation of selenite (Se(Ⅳ))-loaded lepidocrocite (Lp) under neutral anaerobic conditions, and revealed the key roles of initial Fe(Ⅱ) concentration and selenium loading in determining the type of transformation products, phase transition pathways, and their impacts on selenium bioavailability. The results showed that the competitive adsorption between Se(Ⅳ) and Fe(Ⅱ) and the redox reaction between Se(Ⅵ) and Fe(Ⅱ) significantly affected the efficiency of lepidocrocite transformation and the composition of the resulting products. A high Fe(Ⅱ) concentration promoted the transformation of lepidocrocite to goethite, but the presence of Se(Ⅳ) reduced the relative proportion of goethite in the products. Additionally, during this phase in transformation process, there was no significant selenium release in systems with high Fe(Ⅱ) concentrations, while low Fe(Ⅱ) concentrations facilitated the release of small amounts of selenium. These findings are significant for understanding the transformation behavior of lepidocrocite in selenium-containing environments and selenium bioavailability, and provide insights for guiding the remediation of selenium pollution in actual environmental contexts.

Following the hydroponic method, we investigated the effects of exogenous salicylic acid (SA) on the growth, physiology, and cadmium (Cd) absorption and accumulation in sunflowers under varying levels of Cd stress. Sunflower seedlings were irrigated with three concentrations of Cd (10, 20, 40 μmol·L^-1), with SA at the concentration of 100 mg·L^-1 being sprayed on the leaves. The results showed that exogenous SA promoted the growth and biomass of sunflower seedlings, and that the amplitude of such increase first increased and then decreased with increasing Cd concentration. At the Cd concentration of 20 μmol·L^-1, the increases in root length, plant height, root biomass, stem biomass, leaf biomass and total biomass of sunflower seedlings were the largest, which were significantly increased by 7.5%, 7.8%, 25.0%, 7.7%, 10.0%, 11.1%, respectively, compared with that under Cd stress but without SA addition. Exogenous SA increased the contents of chlorophyll a, chlorophyll b, total chlorophyll and carotenoids in sunflower seedlings, reduced the relative conductivity and the malondialdehyde content, and increased the contents of proline and glutathione as well as the activities of superoxide dismutase, peroxidase, catalase and glutathione antioxidant enzymes. Exogenous SA promoted the absorption and accumulation of Cd in sunflower seedlings. With the increases of Cd concentration, the Cd content and accumulation in roots, stems and leaves also increased. Moreover, the Cd transfer coefficient, enrichment coefficient and extraction rate exhibited an increasing trend with increasing Cd concentration. When the Cd concentration was 20 μmol·L^-1, the increase in the Cd transfer coefficient, enrichment coefficient and extraction rate in sunflower seedlings reached the maximum, which were significantly increased by 33.3%, 36.4% and 100.0%, respectively, compared with that under Cd stress but without SA addition, indicating the most significant effect of SA on Cd transport and accumulation. In conclusion, when the Cd concentration was 20 μmol·L^-1, the application of 100 mg·L^-1 SA was beneficial to the growth of sunflower seedlings and their absorption and accumulation of Cd. Our results can provide a reference basis for the application of SA in enhancing the tolerance of plants to heavy metal stress.

This study aims to optimize the combined application scheme of activated iron tailings and selenium-rich mineral powder, providing both technical and theoretical support for promoting selenium accumulation and growth of rice. A pot experiment was conducted. The application level of activated iron tailings was set at 600 kg·hm^-2. There were four addition levels of selenium-enriched mineral powders (CK: 0 kg·hm^-2; Se10: 75 kg·hm^-2; Se20: 150 kg·hm^-2; Se30: 225 kg·hm^-2), along with a sodium selenate treatment (SS20: 1000 kg·hm^-2 silicon fertilizer + 0.48 kg·hm^-2 sodium selenate). We analyzed the effects of the combined application of activated iron tailings and seleniumrich mineral powder on selenium accumulation and physiological and biochemical indices of rice, clarified the optimal application level of selenium-rich mineral powder, and revealed the synergistic mechanism of activated iron tailings and selenium-rich mineral powder to promote rice growth. Results showed that the Se20 treatment was the optimal one, with a rice selenium content of 0.43 mg·kg^-1, representing a 437.50% increase than CK. The highest dry matter per plant was 12.10 g. Furthermore, at the tillering stage of rice, the superoxide dismutase activity and catalase activity of leaves in Se20 group were 49.29% and 63.24% higher than those in CK, respectively. The co-application of activated iron tailings and seleniumrich mineral powder enhanced rice oxidative stress resistance, reduced soil pH and electrical conductivity, and increased soil available silicon and organic carbon content, and thereby increased dry matter accumulation and rice growth.

As an important carbon sink, the accurate estimation of aboveground biomass in bamboo forests is highly important for carbon cycle assessment, ecosystem carbon stock accounting, and the implementation of regional carbon neutrality goals. To resolve the problems of high cost in traditional field surveys and insufficient accuracy of single remote sensing models, we proposed a methodological framework for estimating aboveground biomass in bamboo forests based on Sentinel-2 remote sensing data. Firstly, by analyzing the time-series spectral characteristics of bamboo forests in infrared, near-infrared and other bands, optimal variables were selected to construct a layer-by-layer remote sensing classification method cascaded by multiple machine learning models such as random forest (RF) and XGBoost. This method achieved highprecision separation of bamboo forests from other land-cover types with an overall accuracy exceeding 0.95, which built a spatial foundation for biomass estimation. Secondly, within the bamboo distribution pixels, a model for estimating aboveground biomass was developed by integrating the random forest model with allometric equations. The biomass estimation achieved a coefficient of determination (R²) of 0.82, which outperformed single remote sensing models (with an average accuracy improvement of 28%). We applied this method to estimate the biomass of bamboo forests in Yanping District. The results showed that the aboveground biomass was 6.44×10⁴ tons, with high-value areas mainly being concentrated in the southwestern, northwestern, and eastern parts of the district. This approach provided a low-cost, high-efficiency, and replicable solution for estimating aboveground biomass in bamboo forests, offering critical data support for regional carbon sink inventory compilation, forest carbon sink trading project design, and precision management of bamboo forest ecosystems.

Zunyi native Chinese prickly ash in Guizhou Province has excellent pericarp quality. Predicting the distribution of suitable areas is of great significance for extending the cultivation of this species. Based on the information of 33 distribution points and 27 ecological factors, we adopted the MaxEnt model optimized by ENMeval combined with ArcGIS to predict the distribution of suitable areas for Zunyi native Chinese prickly ash, and analyzed the main ecological factors affecting its distribution. The results showed that the receiver operating characteristic curve area (AUC) of the training sample under both 1970-2000 and 2050s climate conditions was higher than 0.9, indicating that the prediction result was reliable. The dominant ecological factors affecting the distribution of Zunyi native Chinese prickly ash were the precipitation of the driest month, the lowest temperature of the coldest month, isothermality, and the annual temperature range, with the cumulative contribution of those four factors being 97.3%. The areas of highly, moderately, and lowly suitable distribution of this species under the climate conditions of 1970-2000 were 1.35×10⁴, 0.93×10⁴, and 0.57×10⁴ km², respectively. The highly suitable areas were mainly distributed in Chishui, northern Xishui, Tongzi, and Daozhen in northern Zunyi. The highly suitable area of Zunyi native Chinese prickly ash will decrease in both RCP26 and RCP45 climate scenarios by 2050, with the main reduction areas being Xishui, Tongzi, and Daozhen.

Conducting a cost-benefit analysis of nature reserves is conducive to the long-term stable operation and management of the reserves. We analyzed the costs and benefits of forest ecosystem in Shennongjia National Nature Reserve, and clarified the costs borne and benefits obtained by various stakeholders, including the central government, local government, and community residents. Result showed that: (1) The benefits generated by the forest ecosystem in Shennongjia Nature Reserve far outweighed its costs, indicating that the reserve has an economic advantage in terms of returns. (2) While the community residents around the reserve undertook relatively more costs, their benefits were less than those of local governments. The central and local governments should appropriately compensate the costs of community residents. In conclusion, the forest ecosystem of Shennongjia National Nature Reserve provides enormous ecological benefits. A holistic and long-term perspective should be taken for the construction and management of the reserve. Only by properly handling the relationship between the reserve and surrounding community residents can we truly achieve the permanent protection, sustainable utilization and harmonious development of the nature reserve.

As the scientific basis for understanding ecological restoration, the assessment of vegetation resilience provides critical insights that inform decision-making in ecological restoration projects. The use of objective and accurate assessment methods can accurately capture the dynamics of vegetation restoration and provide quantitative decision support for ecological restoration planning. This study focused on vegetation resilience in the context of external perturbations. We analyzed the connotation of vegetation resilience, explored the applicability of different datasets for assessing resilience, and compared the advantages and disadvantages. Furthermore, we reviewed the assessment methods of vegetation resilience under two types of perturbation scenarios: pulse perturbations and press perturbations, and analyzed the advantages, disadvantages, and applicability of these methods in a comparative approach. Finally, a scenario-relevant comparative system for vegetation resilience assessment methods was constructed, laying a foundation for future vegetation resilience assessment and the formulation of ecological protection measures.

Climate change is a major global challenge with profound impacts on the structure and function of forest ecosystems. As a vital carbon sink in the terrestrial ecosystem, forests play a crucial role in climate regulation and biodiversity maintenance. However, global warming is rapidly altering the structure and function of forest ecosystems. To clarify the effects of warming on forest ecosystems and underlying mechanisms, we systematically reviewed research progress both in China and abroad. Based on the findings from simulated warming experiments and ecological modeling studies conducted in China, we explored the effects of warming on nutrient cycling (carbon, nitrogen, phosphorus), hydrological cycle, plant phenology (both above and belowground), plant physiological traits (roots, stems, and leaves), and the structure of soil microbial communities. Warming influenced material cycles and energy flows by affecting the structure and function of soil microbial communities and plant physiological and phenological characteristics, ultimately impacting nutrient supply, carbon sink function, and biodiversity maintenance ability of forest ecosystems. Although there have been significant progresses, it is necessary to further integrate multidisciplinary technologies to conduct long-term and cross-scale studies on the synergistic effects of multiple factors, which would provide theoretical support for the sustainable development of forests.

Nitrous oxide (N₂O) is one of the most important anthropogenic greenhouse gases contributing to global warming. Accurately assessing its emissions and influencing factors is crucial for mitigating climate change and achieving carbon neutrality. The static chamber method, known for its low cost, high accuracy, and broad applicability, is the most widely used approach for measuring soil N₂O emissions. However, factors such as the materials and shape of the chamber, installation methods, sample collection and analysis, data processing, and statistical analysis would directly affect the accuracy and precision of N₂O measurements. Most studies fail to adopt scientifically sound and context-appropriate monitoring protocols, and with problems in the selection of analytical methods. We reviewed the literature on the use of static chamber method for N₂O measurement, summarized and compared common practices and key steps in chamber design, sample processing, flux calculation, and data statistics, aiming to provide a reference for standardizing the method and obtaining more reliable and objective N₂O emission data in future research.

Assessing the health of regional farmland ecosystems from the perspective of uncertainty can improve the scientific basis and accuracy of agricultural economic decision-making. Based on the concept of ecosystem health, we constructed an evaluation index system of farmland ecosystem health considering four dimensions: carrying capacity, productivity, competitiveness, and innovation. Combined with Monte Carlo random simulation, we assessed the influence of weightsetting uncertainty on health evaluation results and revealed the key role of weight changes in the 10-year evaluation. The results showed that grain yield per unit area increased significantly (by 32.9%-56.0%) in Henan Province from 2011 to 2020, but farmland ecosystem health level varied markedly among regions. The Central (Zhengzhou), Southern (Nanyang), and Western (Luoyang) regions were mainly at the sub-healthy level due to high pressure on cultivated land resources, with membership probabilities of 46.3%, 59.3%, and 67.4%, respectively. In contrast, the Eastern (Kaifeng) and Northern (Anyang) regions experienced significant improvements, driven by increased grain yield and enhanced ecosystem productivity. However, insufficient innovation limited the overall health, which remained mainly sub-healthy, with membership probabilities ranging from 39.8% to 45.2%. Based on uncertainty simulation and spatiotemporal analysis, this study accurately identified the trends and main influencing factors of regional farmland ecosystem health levels, and provides theoretical support and data reference for improving the scientific basis and accuracy of agricultural economic decision-making.

As one of the important contents of mine environmental management, the evaluation of the effectiveness of mine ecological restoration is of great significance for testing the effects of ecological restoration. A scientific effectiveness evaluation method is helpful to ensuring the smooth progress of mine ecological restoration projects. Taking the abandoned open-pit mines in the Yangtze River Economic Belt as an example, a watershed scale evaluation method for mine ecological restoration was established by analyzing multi-source mine ecological environment monitoring data, which considered three first-level indicators of social, ecological and economic benefits, and 10 second-level factors such as the improvement of human settlement environment and utilization rate of transition. Remote sensing methods were used to analyze the changes in land use and vegetation coverage before and after the project implementation, and the social, ecological and economic benefits of mine ecological restoration were quantitatively analyzed. The results showed that the total score of the ecological restoration effectiveness of abandoned open-pit mines in the Yangtze River Economic Belt is 74.8, with the scores of social, ecological and economic benefits being 19.4, 39.6, and 15.8, respectively, indicating good benefits. With clarifying the restoration tasks and goals as a prerequisite, the provinces along the Yangtze River Economic Belt should further exploit the potential of land reclamation, actively implement the later management and protection measures, and enhance the various benefits of ecological restoration of abandoned mines. This study is of great significance for mine environmental management and can provide support and decision-making basis for ecological restoration supervision of abandoned mines.

To investigate the effectiveness of AI-assisted passive acoustic monitoring in avian diversity surveys, we installed 14 acoustic monitoring devices in the Xiaolongmen and Baihua Mountain areas of Beijing Baihua Mountain National Nature Reserve. Continuous monitoring was conducted using a triggered recording mode for one year from June 2023 to June 2024. Audio files were transmitted via 4G networks and analyzed by an AI recognition model for bird species identification. Audio clips with species recognition confidence thresholds above 50% underwent manual verification, yielding 116584 valid recordings documenting 90 bird species. Notably, Tundra Swan (Cygnus columbianus) and Bean Goose (Anser fabalis) were first-time regional records. The detection capabilities for nocturnal species like nightjars and owls were stronger. Under a higher confidence threshold, it reduced the number of identified bird species to a certain extent and did not significantly affect the results regarding aspects such as the spatial differences, seasonal variations, and activity rhythms of bird communities. Passive acoustic monitoring of birds can play a crucial role in the long-term monitoring, management, and scientific research of nature reserves. However, standards for data collection, identification, and analysis should be standardized. For bird groups that are not vocal, it is necessary to integrate methods such as line transect surveys and infrared camera monitoring to build a comprehensive, multi-level, and multi-angle monitoring system, thereby enabling more accurate assessment of local bird diversity.