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Background: With growing concern during the COVID-19 pandemic, indoor environmental quality has received significant attention. Radon, a radioactive gas produced from the decay of radium found in soil, rocks, and building materials, can accumulate indoors, posing serious health risks such as lung cancer. University environments, where occupants spend significant time indoors, are particularly susceptible to prolonged radon exposure. Method: This study focused on the estimation of indoor radon concentrations from multiple university buildings in Shanghai. A field investigation was conducted between June 2020 and August 2022. Continuous radon measurements were conducted in the dormitories and classroom buildings. Environmental factors include indoor air temperature and relative humidity. Results: Radon concentrations were influenced by season, floor level, and measurement period, with the highest concentrations recorded during summer and on lower floors due to reduced ventilation. The mean radon concentration in dormitories was 14.8 +/- 9.2 Bq/m3, and in classrooms 12.6 +/- 6.7 Bq/m3, both below national safety limits and lower than those in the pre-pandemic era. Seasonal effect, floor level, and time of measurement were the significant factors for indoor radon concentrations. Conclusion: This study has identified the main factors that affect indoor radon concentration in university campus. The radon concentrations at the lower floor levels remain the highest in the building. The results provide evidence for conducting refined radon monitoring and risk assessment in campus environment, especially during the summer.

期刊论文 2025-06-15 DOI: 10.1016/j.buildenv.2025.112998 ISSN: 0360-1323

The damage caused by soil-borne diseases in Cunninghamia lanceolata (Lamb.) Hook (Cupressaceae), commonly called the Chinese fir, has become increasingly severe in China in recent years. Due to the strong seasonal dependence of the occurrence and severity of these diseases, the ecological processes influencing changes in the composition and function of the plant microbiome during different seasons of pathogen infection have been rarely studied. This study compared the seasonal variations in soil physicochemical properties between the rhizosphere soils of healthy and diseased C. lanceolata in major production areas in China. It further explored the effects of root rot on the composition, structure, and ecological functions of rhizosphere microorganisms. The results demonstrated that seasonal variations significantly influenced the physicochemical properties and microbial composition of the rhizosphere soil in C. lanceolata affected by root rot. Microbiome analysis further confirmed that, within the same season, healthy C. lanceolata contained a greater abundance of ecologically beneficial microbial taxa in the rhizosphere soil compared to diseased trees. These microorganisms may function as bioprotectants. This study enhances our understanding of the structural and functional changes in the rhizosphere soil microbiome associated with soil-borne diseases and provides potential ecological management strategies to improve plant resistance to root rot.

期刊论文 2025-06-01 DOI: 10.1016/j.rhisph.2025.101061

The global impacts of agricultural land conversion on soil erosion and pollution, particularly in tobacco cultivation areas, are well-recognized as significant contributors to soil degradation. These areas are identified as hotspots for environmental concerns due to practices that lead to increased erosion and pollution. From this perspective, this case of study explores fine sediment samples from two areas with tobacco cultivation under different tillage systems and seasonal variations, transport into a headwater, and evaluates, on a local scale: (1) the impact of tillage systems on the geochemical signature of sediments; (2) if whether crop seasonality affects these sediment geochemical signatures. The Conventional Ridge Tillage (CRT) system involves extensive soil exposure and machinery for soil management, while the Mulch Ridge Tillage (MRT) system prioritizes soil conservation and relies on herbicides for weed control. The analytical methodology used to assess the sample element characteristics was Energy Dispersive X-ray Fluorescence (EDXRF). It was applied on the twenty fine sediments (ten of harvest and ten of inter-harvest season of tobacco) to quantitatively assess their inorganic composition. Additionally, Pearson correlation analysis, Hierarchical Cluster Analysis (HCA), and Principal Component Analysis (PCA) were applied on the EDXRF data to highlight the similarities and, thus, providing information to assess the complex data clustering patterns. As a result, the sediment compositions from the two studied soil systems are not similar. The PCA showed that the CRT sediments are characterized by the P, S, K, Ca, and Mn content, presenting a geochemical signature related to manure and fertilizer compared to the MRT, which is correlated with Al, Ti, Fe, Cu, and Zn contents, exhibiting a geochemical signature characterized by the natural soil composition. Therefore, the sediment geochemical signatures might be affected by two phases in the study area: a) tillage system characteristics and b) seasonal soil erosion. These findings underscore the importance of managing soil nutrients to mitigate soil pollution and nutrient exportation to aquatic systems. Moreover, the results emphasize the recommendations for sustainable agricultural practices in tobacco-growing areas to protect environmental quality.

期刊论文 2025-05-19 DOI: 10.1080/15320383.2024.2382462 ISSN: 1532-0383

Allium tuberosum, commonly known as garlic chives, is an underutilized Allium species despite its significant culinary value for its mild garlic flavor and therapeutic potential due to the presence of sulphur-containing compounds with antimicrobial, anti-inflammatory, and antioxidant properties. This study assessed the cultivation potential of A. tuberosum in the non-traditional agro-climatic region of the Western Ghats, focusing on the effects of cultivars and seasonal variations on growth, yield, and quality in two-year field trials. Among the accessions tested, A. tuberosum Kazakhstan CGN-1587 demonstrated the highest yield, producing 157.01 tons of green foliage per hectare. Bright sunshine seasons positively influenced both yield and quality, while the monsoon season induced morphological changes such as increased stem length, reduced leaf width, and decreased stem girth, traits generally considered inferior for market quality. The monsoon also led to increased waste generation, highlighting the need for careful management during this period. Nutritional analysis revealed high concentrations of potassium (5355 mg/kg), phosphorus (691 mg/kg), and sulphur (2484 mg/kg), while biochemical profiling identified bioactive compounds such as flavonoids (3.19 mg/g) and organosulfur compounds, including Allyl Methyl Thiosulfinate (269.00 mg/kg), which contribute to the plant's notable health benefits. These findings support the suitability of A. tuberosum for year-round cultivation in the Western Ghats and its potential for commercialization, especially in regions with similar climatic conditions.

期刊论文 2024-11-18 DOI: 10.3389/fpls.2024.1480510 ISSN: 1664-462X

Riparian soils, together with vegetation, play a crucial role in supporting biodiversity and driving biogeochemical processes within river ecosystems. Conservation of riparian soils and artificial planting are essential for river ecosystem recovery following land degradation. Researchers focus on examining soil nutrients, microbial biomass, and organic acid metabolism in the interactions between plants and soil along riverbanks. However, the seasonal responses of riparian soils to artificial plantations have been infrequently reported in the existing literature. This study investigates the influence of seasonal variations on soil conditions and the growth of artificially planted species in the riparian zones of the Three Gorges Dam Reservoir (TGDR) in China. The species sampled include Cynodon dactylon, Hemarthria altissima, and Salix matsudana. These species provide valuable insight into soil properties along riparian zones, assessing interactions across different seasons: T1 (spring), T2 (summer), and T3 (autumn). The results demonstrated significant seasonal changes in soil organic matter, ammonium nitrogen, nitrate nitrogen, and other indicators between T1 and T3. Apart from invertase activity in H. altissima soil, enzyme activity peaked during T1. Dominant soil bacteria were examined using high-throughput 16S rDNA sequencing, revealing that the available bacteria belong to 62 phyla and 211 classes. Among the most abundant were Proteobacteria and Actinobacteria, averaging over 60 % across all soil samples. Principal component analyses accounted for 62.81 % (T1), 50.57 % (T2), and 54.08 % (T3) of the variation observed in the study, indicating that soil properties were predominantly influenced by the different seasonal phases, assuming all other factors remained constant. Pearson correlation analysis (p < 0.05) identified strong positive correlations between physical properties and all three plant species during T1 (r <= 0.94), as well as significant negative correlations with bacterial communities in T2 and T3 (r <= -1.00). These findings suggest that the selected plant species are well-suited to cultivation in the riparian zone of the TGDR. This study enhances our understanding of seasonal dynamics in riparian environments, offering practical insights into their management.

期刊论文 2024-10-01 DOI: 10.1016/j.gecco.2024.e03174

The carbon stock stored within the biomass of tree species is vital in the forest ecosystem as it contributes significantly to the carbon balance. In addition, the physicochemical properties of soil play a critical role in influencing overall ecosystem health. In the present study the carbon stock and influence of seasonal change on soil physicochemical properties along soil depths in the Shivpuri Nagarjun National Park (SNNP), Nepal were analyzed. The above-ground biomass carbon stock was found to be 227.09 t/ha and below-ground stock was 45.42 t/ha. Tree species Castanopsis tribuloides exhibited the highest values of above and below-ground tree carbon stock. The soil of the study site was sandy loam and slightly acidic. High temperature and moisture in the monsoon season were followed by an increased bulk density during the pre-monsoon with deeper soil layers. The sand, silt, and clay contents did not differ significantly across the seasons and depths. The key soil nutrients, like carbon, total nitrogen, phosphorus, and potassium were high during the monsoon season at the topsoil layer, which gradually declined with increasing depth in all seasons. The study highlights that the total tree carbon stock in the study site is 272.51 t/ha, with significant seasonal and depth-related variations in soil attributes. The monsoon season, characterized by maximum soil moisture and higher concentrations of essential soil components, is crucial in influencing soil physicochemical properties and offers important insights for forest conservation and management.

期刊论文 2024-09-01 DOI: 10.3329/bjb.v53i3.76274 ISSN: 0253-5416

Seasonal changes in vegetation and climate exert significant influences on soil fauna in natural and agricultural ecosystems. Additionally, evidence indicates that interactions between different plant layers promote soil fauna diversity through the variety of resources available. The objective was to assess the edaphic fauna in traditional land use systems, agroforestry systems and natural vegetation, under the influence of rainfall seasonality and plant strata in the semiarid region of Brazil. For this purpose, six types of land use were selected: agroforestry; silvopastoral; slash and burn with intensive use without fallow; slash and burn with six years of fallow; slash and burn with nine years of fallow; and a system representing the natural vegetation of the Caatinga. Edaphic fauna was collected using pitfall traps in the dry and rainy seasons. A total of 43,363 individuals of the edaphic fauna were collected and grouped into taxa, determining abundance, diversity and functional groups. The results revealed higher abundance and diversity of edaphic fauna in the rainy season across all land use systems, but significantly higher numbers in systems with tree strata. The greater the abundance, richness and diversity of trees, the higher the diversity of edaphic fauna (Shannon Index - H: 0.7 < H- < 1) for the seasonal effect. Agroforestry systems were intermediate in the diversity of edaphic fauna (H- < 0.8) compared to other systems. Systems with greater heterogeneity in tree and herbaceous strata were the ones that most increased the diversity and activity of functional groups of edaphic fauna (H < 0.8; 0.5 < r < 0.9). In semiarid conditions, more attention should be given to agricultural production systems with greater tree diversity and interaction between tree and herbaceous strata to conserve the biodiversity of edaphic fauna and improve the soil health.

期刊论文 2024-09-01 DOI: 10.1016/j.ejsobi.2024.103667 ISSN: 1164-5563

In cocoa agroforestry systems, cycling of leaves, pods, and branches are key for organic matter sustenance. We investigated annual total litterfall, annual nutrient stocks in total litterfall, cocoa pods and beans, as well as cocoa leaf decomposition rates in cocoa agroforestry systems under conventional and organic management in Suhum Municipality, Eastern Region of Ghana. The study was conducted using six cocoa agroforests for each management selected from a total of four villages. Litterfall was collected monthly using litterboxes and a litterbag technique was employed to study the rates of leaf decomposition and nutrient release for 12 months. In June and July, total litterfall in organic farms were 94% and 65%, respectively, higher than in conventional farms, but management had no effect on average annual total litterfall of 8.8 t ha-1 yr-1 litterfall. Due to the trees' reduced transpiration, 61% of the annual total litterfall occurred during the dry season. Whereas average leaf litter nitrogen (N) concentration was 17% higher in the rainy season than dry season, potassium (K) concentration was 38% higher during the dry season than rainy season. This likely reflected the contribution of N rich green leaves to litterfall in the rainy season and plant coping strategy to drought leading to K accumulation. Cocoa leaf decomposition was not affected by management. Annual potassium (K) and calcium (Ca) stocks in cocoa pod husk were four and nine-fold, respectively, higher than in cocoa beans. We conclude that organic versus conventional management had no effect on litterfall and cocoa leaf decomposition rather season influenced litterfall quantity and chemistry. Irrespective of management the spreading of cocoa pod husk after harvest will improve internal nutrient cycling in cocoa agroforestry systems.

期刊论文 2024-08-01 DOI: 10.1007/s10705-024-10349-6 ISSN: 1385-1314

Irrigation has distinct impacts on extreme temperatures. Due to the carryover effect of soil moisture into other seasons, temperature impacts of irrigation are not limited to irrigated seasons. Focusing on the North China Plain, where irrigation occurs in both spring (March-April-May) and summer (June-July-August), with a higher proportion of irrigation water applied during spring, we investigate the impact of spring irrigation on summer extreme heat events. Based on partial correlation analysis of data products, we find positive correlations between spring and summer soil moisture, suggesting that spring irrigation-induced water surplus persists into the following summer and affects regional climate by impacting surface energy partitioning. Regional climate simulations confirm cross-seasonal climatic effects and show that spring irrigation reduces the frequency and intensity of summer extreme heat events by approximately -2.5 days and -0.29 degrees C, respectively. Our results highlight the importance of the cross-seasonal climatic effect of irrigation in mitigating climate extremes. Irrigation exerts a stronger impact on extreme temperatures than on mean temperatures. The North China Plain (NCP) is a typical winter wheat-summer maize rotation planting area, where irrigation is necessary in both spring and summer, but with a higher proportion of irrigation water applied during spring. The climatic effects of spring and summer irrigation in the NCP are intertwined due to the carryover effects of soil moisture. Recently, the climatic effect of irrigation in the NCP has been extensively explored, whereas the cross-seasonal effects of irrigation on summer extreme heat events have never been quantified. In this study, we employ the Weather Research and Forecasting model coupled with a demand-driven irrigation algorithm to discern the effects of spring and/or summer irrigation on summer extreme heat events by means of idealized climate simulations. The results show that spring and summer irrigation significantly reduces the frequency and intensity of summer extreme heat events by approximately -6.5 days and -1.0 degrees C, of which spring irrigation contributes about 38% and 30%, respectively. Our findings underline the importance of irrigation-induced climate impacts in mitigating extreme heat events and emphasize that climate change adaptation planning in terms of irrigation must account for cross-seasonal climatic effects. Effect of multi-seasonal irrigation on summer extreme heat events is investigated Spring irrigation is beneficial for reducing summer extreme heat events Irrigation modulates the relationship between spring and summer soil moisture

期刊论文 2024-03-16 DOI: 10.1029/2023GL107094 ISSN: 0094-8276

Forest degradation, driven by human and natural factors, diminishes ecological functions and carbon storage. Understanding the complex dynamics of soil carbon pools is crucial for the global carbon cycle, although these dynamics are poorly understood. This study examines how different thinning intensities influence seasonal soil carbon cycling in degraded forests. ANOVA revealed significant differences in soil properties across treatments (p < 0.05). Redundancy analysis and random forest analyses were used to explore relationships among thinning intensities, soil properties, and carbon sequestration. Thinning significantly altered soil attributes, as revealed by field experiments and data analysis. Moderate thinning (20% intensity) significantly enhanced litter retention and soil nutrient levels year-round (p < 0.05). Seasonal variations affected soil carbon dynamics and lower thinning intensities improved carbon sequestration in spring and summer. Conversely, higher thinning intensities led to carbon loss in autumn and winter. Litter carbon, fine root carbon, and correction factor significantly respond to thinning intensities year-round as examined through redundancy analysis and random forest analyses. Findings indicate moderate thinning effectively enhances soil carbon sequestration in degraded forests. Strategically planned thinning could aid climate change mitigation by boosting forest soil carbon storage, influencing forest management and conservation.

期刊论文 2024-03-01 DOI: 10.3390/f15030449
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