The contribution of litterfall nutrient return to the maintenance of soil carbon pool and nutrient cycling is a crucial aspect of forest ecosystem functioning. Taking 21 tree species in subtropical young plantations as subjects, we investigated the correlation between litterfall nutrient return characteristics and functional traits of leaf and root and. The results showed notable variations in litterfall production, standing crop, and nutrient return across all the examined tree species. Mytilaria laosensis exhibited the highest litterfall production (689.2 g·m-2·a-1) and standing crop (605.1 g·m-2), while Cryptomeria fortunei demonstrated the lowest litterfall production (36.0 g·m-2·a-1) and standing crop (10.0 g·m-2). The nitrogen and phosphorus return amounts of 21 species ranged from 3.0 to 48.3 kg·hm-2 and from 0.1 to 2.0 kg·hm-2, respectively. Castanopsis fissa demonstrated the highest nitrogen return, while Liquidambar formosana exhibited the highest phosphorus return. C. fortunei had the lowest nitrogen and phosphorus return. Results of the stepwise regression analysis indicated that litterfall production exhibited a significant negative correlation with leaf nitrogen content and leaf dry matter content, and a significant positive correlation with fine root tissue density. Additionally, leaf nitrogen content, leaf dry matter content, and specific root length had a significant negative impact on standing crop. The structural equation modelling results indicated that leaf dry matter content had a direct or indirect negative effect on nitrogen return amount through the reduction of litterfall production. Conversely, fine root tissue density had a significant positive impact on nitrogen return amount by increasing litter leaf nitrogen content. Both leaf nitrogen content and leaf dry matter content had direct or indirect negative effects on phosphorus return amount through the reduction of litterfall production. In conclusion, the tree species with low leaf nitrogen content and dry matter content, as well as high fine root tissue density, was recommended for the establishment of plantations in the subtropical zone in order to enhance nutrient cycling through litter decomposition and improve soil fertility and forest productivity.
森林凋落物的养分归还对于维持土壤碳库和养分循环起至关重要的作用。本研究以亚热带人工幼林的21个树种为对象,分析各树种的叶片和根系功能性状与凋落物养分归还特征的关系。结果表明: 不同树种的凋落物量、现存量与养分归还量差异显著,其中米老排的年凋落物量(689.2 g·m-2·a-1)和现存量(605.1 g·m-2)最高,柳杉的年凋落物量(36.0 g·m-2·a-1)和现存量(10.0 g·m-2)最低。21个树种的氮归还量为3.0～48.3 kg·hm-2,其中最高为闽粤栲;21个树种的磷归还量为0.1～2.0 kg·hm-2,最高为枫香。氮、磷归还量最低的树种均为柳杉。逐步回归分析显示,叶片氮含量和叶片干物质含量对凋落物量有显著的负影响,细根组织密度对凋落物量有显著的正影响;叶片氮含量、叶片干物质含量和比根长对现存量有显著的负影响。结构方程模型显示,具有较高叶片干物质含量的树种直接或间接地通过降低凋落物产量来减少氮归还量,而具有较高细根组织密度的树种通过显著增加凋落叶氮含量从而增加氮归还量;具有较高叶片氮含量和叶片干物质含量的树种直接或间接地通过降低凋落物产量从而减少磷归还量。在亚热带营造人工林时,要考虑叶干物质含量低、细根组织密度大的树种,以提高林地凋落物产量和氮、磷养分归还量,进而提高土壤肥力和林地生产力。.

In recent years, heightened environmental concerns linked to agriculture have surged, with soil degradation standing out as a global issue. However, prevailing sustainability assessment methodologies in agriculture often overlook soil systems due to their intricate nature. This study aims to develop a methodology for evaluating soil degradation in agricultural practices using exergy regeneration costs. These costs determine the exergy required to restore soil fertility to pre-harvest levels. The methodology covers key soil factors like nutrients, organic matter, and prevalent issues like salinity, acidification, and erosion. For each of these factors, exergy regeneration costs are determined based on the energy needed to execute an optimal process for reverting the soil to its original or ideal state. The methodology has been applied to data from agricultural trials, showing that the calculated soil replacement cost is significantly higher compared to one of the most energy-demanding processes in agriculture, the use of urea. This demonstrates that agricultural soil degradation needs to be quantified for a correct evaluation of agricultural practices and their sustainability.

Wheat production is intrinsically linked to global food security. However, wheat cultivation is constrained by the progressive degradation of soil conditions resulting from the continuous application of fertilizers. This study aimed to examine the effects of deep tillage on rhizosphere soil microbial communities and their potential role in improving soil quality, given that the specific mechanisms driving these observed benefits remain unclear. Soil fertility in this research was evaluated through the analysis of various soil parameters, including total nitrogen, total phosphorus, total potassium, available phosphorus, and available potassium, among others. The high-throughput sequencing technique was utilized to examine the rhizosphere microbial community associated with deep tillage wheat. The findings indicated that deep tillage cultivation of wheat led to reduced fertility levels in the 0-20 cm soil layer in comparison with non-deep tillage cultivation. A sequencing analysis indicated that Acidobacteria and Proteobacteria are the dominant bacterial phyla, with Proteobacteria being significantly more abundant in the deep tillage group. The dominant fungal phyla identified were Ascomycota, Mortierellomycota, and Basidiomycota. Among bacterial genera, Arthrobacter, Bacillus, and Nocardioides were predominant, with Arthrobacter showing a significantly higher presence in the deep tillage group. The predominant fungal genera included Mortierella, Alternaria, Schizothecium, and Cladosporium. Deep tillage cultivation has the potential to enhance soil quality and boost crop productivity through the modulation of soil microbial community structure.

Deltamethrin is used against plant pests (e.g., mites and ants) and, in farm animals, against biting insects because of its acaricidal and repellent effects against ticks, thus protecting the sheep and cattle from the transmission of pathogens. However, its impact on the environment still needs to be fully evaluated. This study evaluates the impact of this pyrethroid on the nitrogen-fixing nodules in Medicago truncatula, a model legume. This research compares nodular biomass and root weight between a deltamethrin-treated section and an untreated control section of this legume. Our results indicate a significant reduction in the biomass of nitrogen-fixing nodules in the treated grove, suggesting that deltamethrin negatively affects the symbiotic relationship between M. truncatula and nitrogen-fixing bacteria. This reduction in nodule formation can impair soil fertility and plant growth, highlighting an ecological risk associated with pyrethroid\'s use in livestock farming. These findings underscore the need for a shift towards Green Veterinary Pharmacology (GVP), which promotes environmentally sustainable practices in managing livestock health. By minimizing our reliance on harmful chemical treatments, GVP offers viable solutions to protect and enhance ecosystem services such as biological nitrogen fixation that are essential for maintaining soil health and agricultural productivity.

The soil of urban green spaces is severely degraded due to human activities during urbanization, and it is crucial to investigate effective measures that can restore the ecological functions of the soil. This study investigated the effects of plant growth promoting bacteria (Bacillus clausii) and Fe-modified biochar on soil fertility increases and mechanisms of carbon sequestration. Additionally, the effects on C-cycling-related enzyme activity and the bacterial community were also explored. Six treatments included no biochar or Bacillus clausii suspension added (CK), only Bacillus clausii suspension (BC), only biochar (B), only Fe-modified biochar (FeB), biochar combined with Bacillus clausii (BBC), and Fe-modified biochar combined with Bacillus clausii (FeBBC). Compared with other treatments, the FeBBC treatment significantly decreased soil pH, alleviated soil alkalization, and increased the alkali-hydro nitrogen content in the soil. Compared to the individual application of FeB and BC, the FeBBC treatment significantly improved aggregates\' stability and positively improved soil fertility and ecological function. Additionally, compared to the individual application of FeB and BC, the soil organic carbon (SOC), particulate organic carbon (POC), and soil inorganic carbon (SIC) contents for the FeBBC-treated soil increased by 28.46~113.52%, 66.99~434.72%, and 7.34~10.04%, respectively. In the FeBBC treatment, FeB can improve soil physicochemical properties and provide bacterial attachment sites, increase the abundance and diversity of bacterial communities, and promote the uniform distribution of carbon-related bacteria in the soil. Compared to a single ecological restoration method, FeBBC treatment can improve soil fertility and carbon sequestration, providing important reference values for urban green space soil ecological restoration.

Hot pepper is one of the most important spice vegetable crops in Ethiopia and is widely cultivated for dry pod production. However, its productivity is low in Ethiopia due to degraded soil fertility and an unbalanced nutrient supply in the soil. An experiment was conducted to evaluate the effect of NPS fertilizer and cattle manure (CM) on soil chemical properties and hot pepper dry pod yield under irrigation in Jabi Tehnan. This experiment was arranged in factorial combinations of four NPS fertilizer (0, 100, 200, and 300 kg ha-1) and four CM (0, 5, 10, and 15 t ha-1) levels in a randomized complete block design with three replicates. Soil chemical properties, hot pepper phenology, growth, yield, and yield-related traits were recorded and analyzed using SAS software version 9.4. The main and interaction effects of NPS and CM fertilizers had a significant effect on soil chemical properties, hot pepper phenology, growth, yield, and yield-related traits. The combination of NPS fertilizer and CM significantly increased soil chemical properties and hot pepper traits. However, soil chemical properties and hot pepper yield traits showed a somewhat decreasing trend as the combination levels of two fertilizers further increased. The highest marketable (2.90 t ha-1) and total dry pod yield (2.99 t ha-1) were produced at the combination of 200 kg NPS ha-1 and 15 t CM ha-1. However, the partial budget analysis showed that the combination of 200 kg NPS ha-1 and 10 t CM ha-1 had the highest net benefit with an acceptable MRR and can be recommended for profitable hot pepper dry pod production in the study area. However, the experiment was limited to a single location and variety; it should be repeated at multiple locations over the seasons to make a strong recommendation.

The argan (Argania spinosa L. Skeels) ecosystem is severely degrading in arid and semi-arid lands due to climate change, particularly in terms of density loss and reforestation failure. Thus, it is important to adopt innovative effective sustainable practices to optimize the densification and reforestation success of the argan tree. The purpose of the present research was to investigate the combined effect of subsurface water retention technology (SWRT) and the use of native arbuscular mycorrhizal fungi (AMF) on edaphic, growth, physiological and biochemical parameters of field-grown argan seedlings in the Essaouira region, Morocco. In this experiment, one-year-old argan seedlings were transplanted in the absence and presence of biodegradable plastic and AMF. Our findings revealed that the application of SWRT enhanced soil profile moisture up to 640% at 40 cm depth compared to the control. The combination of this technology with AMF also improved soil fertility. Furthermore, the application of SWRT, with or without AMF, significantly enhanced argan seedling height (208 and 168%, respectively), stomatal conductance (54 and 33%, respectively), and chlorophyll fluorescence (21 and 20%, respectively). Similarly, the combined application of SWRT and AMF significantly improved protein and sugar content (36 and 57%, respectively), as well as antioxidant enzyme activities (peroxidase and polyphenol oxidase) and chlorophyll pigments content compared to the control. However, this treatment reduced malondialdehyde and H2O2 content in the argan leaves. As a summary, SWRT technology combined with AMF may be used as a valuable strategy to promote the success of argan reforestation and to limit soil erosion and desertification in arid and semi-arid climates.

To investigate the effects of biogas slurry substitution for fertilizer on rice yield, fertilizer utilization efficiency, and soil fertility, a field experiment was conducted on rice-wheat rotation soil in the Chaohu Lake Basin for two consecutive years, with the following six treatments: no fertilization (CK), conventional fertilization (CF), optimized fertilization (OF), biogas slurry replacing 15% of fertilizer (15% OFB), biogas slurry replacing 30% of fertilizer (30% OFB), and biogas slurry replacing 50% of fertilizer (50% OFB). The field experiment results showed that, compared with CF treatment, OF treatment in 2022 and 2023 significantly increased (p < 0.05) rice yield, promoted the uptake of nitrogen (N), phosphorus (P), and potassium (K) by grains and straws, improved fertilizer utilization efficiency, and increased the contents of soil organic C (SOC), NH4+-N, NO3--N, hydrolysable N, and available P. The 15% OFB and 30% OFB treatments significantly increased (p < 0.05) rice grain and straw yields compared with CF treatment, and rice grain and straw yields were the highest in the 30% OFB treatment. Compared with CF and OF treatments, 30% OFB treatment significantly increased (p < 0.05) the N, P, and K uptake of grains and straws and increased the fertilizer utilization efficiency. Compared with CF treatment, the grain yield of 50% OFB treatment was significantly decreased (p < 0.05) in 2022, and there was no significant difference in 2023, which may be because the biogas slurry was applied before planting in 2023 to provide more nutrients for early rice growth. Compared with CF treatment, 30% OFB treatment significantly increased (p < 0.05) the contents of SOC, NH4+-N, available K, and hydrolysable N. In summary, optimizing N and K topdressing methods can increase rice yield and improve the fertilizer utilization efficiency and soil fertility. The 30% OFB treatment resulted in the highest rice yield, fertilizer utilization efficiency, and improved soil fertility, indicating that biogas slurry replacing 30% of fertilizer was the best application mode for rice in this region.

UNASSIGNED: The application of mineral fertilizers deteriorates soil properties and affects crop yield and nutritional properties. However, plant growth-promoting microorganisms (PGPM- Serendipita indica, phosphorus solubilizing bacteria (PSB), and vesicular arbuscular mycorrhizae (VAM)) have great potential to reduce fertilizers and improve soil fertility, crop yield, and nutrient uptake and mitigate the environmental effect of mineral fertilizers.
UNASSIGNED: Hence, a field experiment was conducted involving nine treatments to evaluate the effects of PGPM along with 50% or 100% of the recommended dose of fertilizers on plant growth, soil fertility, nutrient uptake, and onion productivity.
UNASSIGNED: Results indicated that 100% RDF combined with S. indica or PSB led to improved plant growth, and higher nutrient concentrations in both leaves and bulbs of onions compared to RDF alone. Moreover, the application of 100% RDF with S. indica increased total dry matter yield by 11.5% and 7.6% in the 2018-2019 and 2019-2020 seasons, respectively, compared to 100% RDF alone. This treatment also resulted in the highest nutrient uptake, with N uptake increasing by 6.9%-29.9%, P by 13.7%-21.7%, K by 20.0%-23.7%, and S by 18.1%-23.4%. Additionally, the combination of 100% RDF with S. indica inoculation led to a notable increase in bulb yield, with increments of 16.2% and 13.9% observed in 2018-2019 and 2019-2020, respectively, compared to 100% RDF alone. Similarly, the application of 100% RDF along with PSB inoculation resulted in an increase in bulb yield by 7.2% and 9.4% in the respective years. However, VAM did not exhibit satisfactory performance or improvements in the onion crop.
UNASSIGNED: Overall, the study suggests that combining 100% RDF with S. indica or PSB can enhance onion productivity and nutrient use efficiency. The present study may open a new avenue of PGPM application in enhancing onion yield and improving the bulb quality as well as soil health. However, field trials across different regions and soil types are necessary to validate these findings for practical adoption by farmers.

BACKGROUND: Straw incorporation serves as an effective strategy to enhance soil fertility and soil microbial biomass carbon (SMBC), which in turn improves maize yield and agricultural sustainability. However, our understanding of nitrogen (N) fertilization and straw incorporation into soil microenvironment is still evolving. This study explored the impact of six N fertilization rates (N0, N100, N150, N200, N250, and N300) with and without straw incorporation on soil fertility, SMBC, enzyme activities, and maize yield.
RESULTS: Results showed that both straw management and N fertilization significantly affected soil organic carbon (SOC), total N, SMBC, soil enzyme activities, and maize yield. Specifically, the N250 treatment combined with straw incorporation significantly increased SOC, total N, and SMBC compared to lower fertilization rates. Additionally, enzyme activities such as urease, cellulase, sucrose, catalase, and acid phosphatase reached their peak during the V6 growth stage in the N200 treatment under for both straw management conditions. Compared to N250 and N300 treatments of traditional planting, the N200 treatment with residue incorporation significantly increased yield by 8.30 and 4.22%, respectively. All measured parameters, except for cellulase activity, were significantly higher in spring than in the autumn across both study years, with notable increases observed in 2021.
CONCLUSIONS: These findings suggest that optimal levels of SOC, soil total N (STN), and SMBC, along with increased soil enzyme activities, is crucial for sustaining soil fertility and enhancing maize grain yield under straw incorporation and N200 treatments.