Search Results (1,609)

Rainfed wheat plays a vital role in global food security, particularly in regions where water availability is a limiting factor. Identifying homogeneous areas with a similar yield potential is essential for optimizing resource allocation, improving agricultural sustainability, and enhancing water resource management. Unlike previous studies that primarily focused on cropland suitability, this study presents an integrated approach to delineate homogeneous areas for the rainfed wheat yield using advanced mechanistic analysis and multi-criteria decision-making techniques. Additionally, it examines the homogeneity of these areas in terms of the actual yield relative to the potential yield. Kurdistan province in Iran was selected as the study area. Key phenological stages of wheat growth—germination, flowering, and seed filling—were determined using a day-growth model. A set of four primary criteria—precipitation, temperature, soil properties, and topography—along with twenty sub-criteria were selected based on expert knowledge and previous research. The Fuzzy-AHP method was employed to assign weights to each factor, and a weighted linear combination approach was used to generate a final classification map. The results categorized the study area into five suitability classes: currently unsuitable (N2 and N1), somewhat suitable (S3), moderately suitable (S2), and very suitable (S1), in accordance with the FAO standard framework. These classifications highlighted significant yield variations among the zones. The findings revealed that the highest and lowest average rainfed wheat yields were observed in classes S1 and N2, respectively, with yield-to-potential yield ratios ranging from 75% in S1 to 20% in N2. This research underscores the potential of spatial analysis in enhancing precision agriculture and water resource management, contributing to more resilient food production systems in water-scarce regions. Full article

Vegetation phenology has lately gained attention in the context of studying human-induced climate change and its effects on terrestrial ecosystems. It is typically studied on various regional and temporal scales. This research focused on the microscale in dolines on the Northernmost part of the Dinaric Alps. The aim was to determine the timing of flowering onset and relate it to topographic and ecological conditions. We studied (1) the floristic gradient along N–W transects divided in 2 m × 2 m plots, from top slopes to the bottom of dolines, and identified discrete groups in relation to this gradient and (2) provided their diagnostic species and communities. The results indicate that the early spring onset of flowering of ground vegetation in the bottom and lower slopes of dolines is stimulated by high spring moisture and nutrient availability, as well as the open canopy of the mesophilous deciduous forests. The flowering onset on the upper slopes and karst plateau starts later, which is due to the precipitation peak in May/June and higher temperatures and light availability of the open canopy of thermophilous deciduous forests. The delayed onset of flowering in late summer in rocky crevices and rocky places is due to a particular physiology stimulated by the harsh site conditions. The phenology pattern along the doline topographic gradient is inverse to general patterns in vegetation phenology. Further study on the role of doline soils should be made to study their impact on phenology. Full article

The increasing soil pollution has accelerated the implementation of new agricultural regulations that significantly limit the use of synthetic nitrogen (N) fertilizers. Consequently, plants are likely to experience nutrient stress, leading to decreased productivity and potential threats to food security. To address these critical challenges, microbial-based biostimulant (BS) products, which utilize metabolites from microorganisms, offer a sustainable and eco-friendly solution to mitigate plant nutrient stress. This study evaluated the effects of the radicular application of a microbial-based BS containing L-α-amino acids on lettuce and pepper crops under two nitrogen regimes: optimal N availability and N stress (NS). Various parameters, including growth, production, soluble proteins, photosynthetic pigment content, and oxidative stress markers, were assessed. Under optimal N conditions, BS application enhanced commercial biomass in lettuce and vegetative biomass in pepper, indicating that BSs can reduce the need for nitrate uptake and endogenous amino acid synthesis, thereby conserving energy for other physiological processes. Despite BS application, NS conditions significantly reduced vegetative and reproductive growth in both species. However, BS treatment in pepper plants increased chloroplast pigments, improving light absorption and photosynthetic efficiency. The reduction in the carotenoid/chlorophyll ratio suggests efficient N allocation to growth and production. Thus, BS application proved effective in mitigating NS in pepper plants, enhancing pepper production, while under optimal conditions, it improved lettuce yield, particularly commercial biomass. These findings underscore the potential of symbiotic microbial-based BSs as a promising tool for sustainable agriculture under reduced N availability. Full article

Crop rotation and microbial driving force significantly influence soil phosphorus (P) bioavailability and crop yield. However, differences in underlying microbial mechanisms in rotations remain unclear. We examined rice yield, P uptake, soil and microbial P contents, enzyme activity, and P functional genes over six years (2016–2022) to elucidate microbial mechanisms driving rice yield in rice–wheat (RW) and rice–oilseed rape (RO) rotations. RO significantly increased rice yield and plant P uptake by 9.17% and 20.70%, respectively, compared to RW. Soil total (TP) and available (AP) P contents were significantly lower (4.83% and 18.31%, respectively) under RO than RW, whereas microbial biomass phosphorus (MBP) and acid phosphatase activity (EP) were greater (39.40% and 128.45%, respectively). PICRUSt2 results revealed that RO increased phoA phoB (alkaline phosphatase), phnX (phosphonoacetaldehyde hydrolase [EC:3.11.1.1]), gcd (Quinoprotein glucose dehydrogenase [EC:1.1.5.2]), and ppaC (manganese-dependent inorganic pyrophosphatase) and decreased phnD (phosphonate transport system substrate-binding protein), ugpE (sn-glycerol 3-phosphate transport system permease protein), ugpA (sn-glycerol 3-phosphate transport system permease protein), and phnO ((aminoalkyl)phosphonate N-acetyltransferase [EC:2.3.1.280]) abundance. Random forest analysis showed that ppaC, phnD, gcd, and phnX were important for rice yield and plant P uptake. Partial least squares analysis revealed that RO indirectly increased rice yield by influencing MBP and affecting plant P uptake through P functional genes. Overall, RO improves rice yield and P bioavailability by altering P functional genes (ppaC, phnD, gcd, and phnX), providing new perspectives on crop–microorganism interactions and resource use efficiency. Full article

Composite planting has become one of the primary agricultural practices promoted in recent years, especially in the northwest inland cotton regions of China, where various economic trees and crops are intercropped with cotton. However, research on the microclimatic differences affecting cotton growth and the nutrient allocation strategies for cotton’s key economic organs (i.e., seed, batt, and shell) in strip composite cropping systems remains limited. In this study, we examined the nutrient allocation strategies of cotton under multiple composite cropping patterns and proposed the most suitable cultivation patterns for this region in the northwest inland region of China, utilizing an allometry partitioning index and ecological stoichiometry, based on a long-term positional experiment. The results revealed that the nutrient distribution of cotton was of equal speed with the combined planting with trees, while there was an allometric distribution index of N and P between the combined planting with maize. The effect of the compound planting mode on the nutrient-use efficiency of cotton was mainly reflected in the organ differentiation stage of its reproductive growth stage. Specifically, cotton showed lower nutrient-use efficiency in reproductive organs when intercropped with low shrubs and herbaceous crops, likely due to the insufficient protective capacity of these plants for cotton. Interestingly, strip intercropping with tall trees improved cotton’s nutrient-utilization efficiency. However, it also resulted in reduced nitrogen and phosphorus content in cotton batt. Moreover, soil indicators such as available nitrogen and electrical conductivity positively influenced the nutrient uptake of cotton shells and roots, while soil phosphorus promoted the nutrient absorption of cotton seed but inhibited the nitrogen and phosphorus of cotton shell and the nitrogen of cotton batt. These findings suggest that nutrient partitioning in cotton is influenced by a variety of soil factors. According to these results, the combined planting pattern of cotton and apple trees should be considered in practice to improve cotton yield and economic benefits in the northwest inland region of China. Full article

The application of slow-release fertilizers is essential for improving fertilizer utilization efficiency and promoting sustainable agricultural development. Unlike traditional single organic polymer-coated or inorganic-coated fertilizers, this study utilized biodegradable modified polyvinyl alcohol (PVA) as a binder and cheap, readily available phosphogypsum–bentonite as an inorganic coating material to develop a novel slow-release potassium magnesium sulfate fertilizer (SRPMSF). This study initially examined the influence of SA dosage on PVA properties. XRD, FTIR, TGA, and water resistance analyses revealed that sodium alginate exhibits good compatibility with polyvinyl alcohol, enhancing its heat and water resistance. Ultimately, PVA–SA-2 (1.2% sodium alginate) was chosen as the optimal binder for SRPMSF production. Furthermore, this study investigated the impact of bentonite on the physical and slow-release properties of the SRPMSF by varying the phosphogypsum-to-bentonite ratio. This experiment included five treatment methods: the treatments consist of SRPMSF-1 (0 g bentonite), SRPMSF-2 (phosphogypsum/bentonite ratio of 4:1), SRPMSF-3 (3:2), SRPMSF-4 (2:3), and SRPMSF-5 (1:4). A control group (PMSF) was also included. The results indicated that, as the bentonite content increased, both the particle size and compressive strength of the coated slow-release fertilizer increased, with the SRPMSF particle sizes ranging from 3.00 to 4.50 mm. The compressive strength of the SRPMSF ranged from 20.85 to 43.78 N, meeting the requirements for industrial production. The soil column leaching method was employed to assess the nutrient release rate of the fertilizers. The experimental results indicated that, compared to the PMSF, the SRPMSF effectively regulated nutrient release. Pot experiments demonstrated that the SRPMSF significantly enhanced garlic seedling growth compared to the PMSF. In conclusion, a new type of slow-release fertilizer with good slow-release performance is prepared in this paper, which can improve the utilization rate of fertilizer and reduce the economic loss and is conducive to the sustainable development of agriculture. Full article

Sweet corn (Zea mays convar. saccharata var. rugosa) is an important crop in the United States (US), particularly in the southeastern region. While effective nitrogen (N) management is essential for optimizing yields, the sandy soils and variable precipitation in this region impact N uptake. This study evaluates the effects of several N rates (ranging from 224 to 336 kg ha⁻¹) and N fertilizer application timing (N fertilizer applied at emergence and side-dress stages) on sweet corn growth and yield under the subtropical environmental conditions of the southeastern US. Field experiments were conducted over three years in the states of Georgia (2020) and Alabama (2021 and 2022). In general, the weather conditions of each season had a direct impact on sweet corn growth, development, and yield parameters. Among all locations, the season in Alabama (2022) allowed for the highest yields (17,380 kg ha⁻¹), which could be attributed to favorable weather conditions that required moderate nitrogen application rates (224–280 kg ha⁻¹). Contrarily, the weather conditions of Alabama in 2021 and Georgia in 2020 impacted soil N availability, consequently leading to negative effects on sweet corn growth. Overall, N fertilizer management strategies are indicated to be region- and season-specific in order to enhance sweet corn production while protecting the environment from excessive N losses. Further research is still required to refine these strategies and improve predictive models for diverse climatic conditions. Full article

Small-grain producers in the southern Pannonian Plain prefer winter barley production in poor soils and drought-prone areas, assuming higher resource use efficiency in barley than in wheat. Similarly, triticale is known to perform well in low-fertility soils and dry environments. However, information about the comparative performance of these crops within the same trials is less available for the Pannonian environment. Therefore, this study aimed to compare the grain yield and nitrogen use efficiency traits of winter wheat, triticale, and two-rowed and six-rowed barley cultivars across different N applications in different growing seasons and locations in the Pannonian Plain. The study was conducted over two seasons at three locations (Novi Sad, Sremska Mitrovica, and Sombor) using a split-plot design. Treatments consisted of winter wheat, triticale, and two-rowed and six-rowed barley under three nitrogen fertilization levels of low, moderate, and high. Averaged across species, the reduction in grain yield in 0 N compared to 100 N was 1218 kg ha⁻¹ (15.7%) in wheat, 1037 kg ha⁻¹ (11.6%) in triticale, 1128 kg ha⁻¹ (13.7) in two-rowed barley, and 1340 kg ha⁻¹ (17.1%) in six-rowed barley. Grain yield was closely related to nitrogen uptake, showing a relationship (R²) from 0.652 in triticale to 0.956 in six-rowed barley. Nitrogen use efficiency showed a positive relationship with nitrogen uptake efficiency, while the relationship with nitrogen utilization efficiency was insignificant. There was a notable difference between crops in terms of grain yield and nitrogen use efficiency traits. Notably, two-rowed barley outperformed wheat in terms of grain yield and nitrogen use efficiency, while wheat outperformed six-rowed barley. Triticale showed the highest yield among all the studied cereal crops, attributed to increased nitrogen use efficiency and uptake, especially under low fertilization conditions. Full article

Microplastics and heavy metals (HMs) in soil pose significant environmental and health risks, yet the interactions between mulch film residues and HMs, and their effects on maize productivity, remain poorly understood. This study examined the impacts of long-term traditional polyethylene mulch film (TMF) and biodegradable mulch film (BMF) residues on soil properties, maize root accumulation of HMs, the arbuscular mycorrhizal fungi (AMF) community, and maize productivity under open field conditions. TMF residues significantly increased the soil total carbon (TC), C/N ratio, and bioaccumulation coefficients (BACs) of arsenic (As) and cadmium (Cd) while lowering soil pH and water content. These changes altered AMF colonization and enriched the Paraglomus genus, leading to enhanced maize leaf antioxidant activity and reduced chlorophyll content, although maize growth was not statistically affected. In contrast, they improved soil nutrient availability (e.g., nitrogen and phosphorus), increased TC and the C/N ratio, and reduced soil pH. Notably, BMF residues decreased the BACs of As and Cd, reduced AMF spore density without altering community structure, and ultimately enhanced maize biomass. These effects were associated with BMF’s ability to lower pH and chelate HMs, thereby mitigating their bioavailability and promoting plant growth. Furthermore, the enriched abundance of AMF species, particularly from the Claroideoglomus genus, facilitated heavy metal chelation and reduced HM accumulation in plants. The findings underscore the potential of BMF and AMF for co-remediation of microplastics and HMs, highlighting the importance of mulching strategies for sustainable agriculture. Full article

Peat swamp wetlands, crucial carbon pools in terrestrial ecosystems, significantly impact regional carbon cycling and climate change. In this study, the peat swamp wetland in the Altay Mountains was selected as the research object. In July 2023, soil samples were collected in situ from a depth of 0–80 cm of the peat swamp wetland. Subsequently, the contents of soil organic carbon (SOC), dissolved organic carbon (DOC), particulate organic carbon (POC), and the physicochemical properties of the soil samples were determined. The distribution characteristics of soil organic carbon and its active carbon fractions at different soil depths and their influencing factors were investigated. The results demonstrate that (1) SOC, POC, and DOC concentrations were significantly higher in subsurface layers (20–80 cm) than in those of surface layers (0–20 cm), with SOC and POC peaking at 20–40 cm and DOC predominantly accumulating at 40–80 cm. (2) The concentrations of SOC, POC, and DOC reached minima at 0–10 cm, accounting for 17.25%, 16.91%, and 6.46% of the total 0–80 cm profile, respectively. POC represented 76.46% of SOC throughout the profile. (3) Available phosphorus (AP), total nitrogen (TN), ammonium nitrogen (NH₄⁺N), and soil moisture (SM) accounted for an average of 68.94% of the variation in soil organic carbon and active carbon fractions at a depth of 0–80 cm. Higher levels of soil moisture and total nitrogen content emerged as the primary factors responsible for the reduction in soil organic carbon and active carbon fractions. In shallow soils (0–20 cm), an increase in the content of available phosphorus and ammonium nitrogen contributed to a decline in the soil’s active carbon fraction. Conversely, the situation was reversed in deeper soils. This study thus offers scientific insights into alpine peat bog wetland soil carbon dynamics and environmental responses. Full article

Drip irrigation with plastic mulch is widely used to save water and improve fertilizer efficiency in arid regions in Xinjiang. However, farmers freely use irrigation water in pursuit of a high cotton yield, and the impact of different irrigation amounts on nitrous oxide (N₂O) emissions is still unclear. A field experiment was conducted in 2023 in Xinjiang, China, with drip-irrigated cotton (Gossypium hirsutum L.) to determine N₂O emissions with different irrigation intensities. The different irrigation treatments were designed as follows: irrigation was performed to maintain soil moisture at (1) an 80% field capacity (Q80); (2) 90% field capacity (Q90); and (3) 100% field capacity (Q100). The results showed that the yield of cotton decreased with the increase in irrigation intensity. A 100% field capacity is beneficial for ammonium and nitrate transformation. The N₂O emissions remained at a relatively low level during the non-irrigated fertilization period. In every irrigation and fertilization cycle, the N₂O emissions were mainly concentrated during the process from wet to dry. The peak occurred during days 1–3 of irrigation. Throughout the growth period, the cumulative N₂O emissions were 1.15, 1.48, and 2.63 kg N ha⁻¹ under the Q80, Q90, and Q100 treatments, respectively. As the irrigation intensity increased, the dominant species of soil bacteria and fungi showed substitution, while the dominant species of soil actinomycetes were not replaced. Fungi, actinomycetes, the available potassium, and the carbon to nitrogen ratio were positively correlated with nitrous oxide emissions, and the soil temperature was negatively correlated with nitrous oxide emissions. These results demonstrate that increased irrigation could increase the risk of greenhouse gas emissions when using plastic mulch with drip irrigation. Full article

Microbial necromass carbon (MNC) is crucial for soil carbon sequestration in bamboo (Phyllostachys edulis) forests. However, the response of MNC to bamboo-sourced organic fertilizers (BSOF) prepared by composting bamboo plant growth-promoting microorganisms and bamboo residues remains unclear. This study examined MNC and its contribution to soil organic carbon (SOC) in Moso bamboo plantations under four BSOF treatments: control (CK, 0 t·hm⁻²), low fertilizer application (LF, 7.5 t·hm⁻²), medium fertilizer application (MF, 15 t·hm⁻²), and high fertilizer application (HF, 30 t·hm⁻²) across 0–20 cm and 20–40 cm soil layers. In these two layers, HF and MF significantly (p < 0.05) increased the total MNC, fungal necromass carbon (FNC), and their contributions to SOC compared to CK, and HF led to higher (p < 0.05) bacterial necromass carbon (BNC) levels and SOC contributions than LF and CK. Soil depth and BSOF treatment were found to interact significantly. A random forest model showed that in the 0–20 cm layer, SOC was the best predictor of total MNC and FNC, whereas available potassium was optimal for BNC. Nitrate-nitrogen (NO₃⁻-N) was the top predictor for total MNC, BNC, and FNC in the 20–40 cm layer. Partial least squares path modeling indicated that available soil nutrients directly influenced BNC and FNC, affecting SOC accumulation. These findings suggest a new method for enhancing soil carbon sequestration in bamboo forests. Full article

A sustainable Goji berry (Lycium barbarum L.) planting system that integrates forage radish cover crops (Raphanus sativus L.) and animal manure has been established in northwestern China. This study investigated the effects of different cropping systems and manure application levels on soil physicochemical properties, microbial community structure, and L. barbarum yield under field conditions. A split-plot design was used, with the main-plot treatments consisting of two cropping systems and the sub-plot treatments involving three manure application levels. The results showed that compared to L. barbarum monocropping, cover cropping with R. sativus led to a decrease in soil bulk density (1.90%) and increase in soil electrical conductivity (11.5%), nutrient contents (total N and available N, P, and K: 30.3–138%), and microbial biomass (C: 79.0%; N: 184%). Cover cropping additionally enhanced the community diversity and richness of soil bacteria. Beta-diversity analysis revealed significant differences in bacterial rather than fungal community composition among various treatments. The bacterial network showed a lower ratio of positive to negative correlations and reduced complexity in response to cover cropping, which contrasted with fungal network patterns. Integration of cover cropping and medium manure application increased fruit yield by 8.71%. Cover crops and manure influenced soil microbial diversity mainly through their positive effects on soil total and available N contents. Full article

This study investigates the seasonal dynamics and stoichiometric characteristics of carbon (C), nitrogen (N), and phosphorus (P) in four representative tree species—Juglans mandshurica Maxim., Phellodendron amurense Rupr. Quercus mongolica Fischer ex Ledebour and Fraxinus mandschurica Rupr.—at the Harbin Urban Forestry Demonstration Base, over the period 2022–2024. We monitored the nutrient content in tree leaves, trunks, branches, shrubs, herbaceous plants, and soil. Specifically, leaf N content in J. mandshurica decreased from 2.5% in May to 1.2% in November, while leaf P content in P. amurense dropped from 0.15% in June to 0.08% by the end of the growing season. Nutrient content in tree trunks and branches increased in the later growth stages, with trunk C content in Q. mongolica rising from 45% in May to 52% in November. Soil nutrients generally decreased over the growing season, with soil P content in F. mandshurica plantations declining from 0.12% in May to 0.06% in September. Moreover, the C:N and C:P ratios in tree and herb leaves, as well as in soil, increased during the growing period, while the N:P ratio in shrubs increased towards the end of the growth cycle. The study found significant correlations between specific nutrients in the leaves of trees and their surrounding soils. For instance, leaf C in J. mandshurica was positively correlated with soil C, while herbaceous plant P was positively correlated with soil N and leaf N with soil P. These relationships suggest that leaf N absorption is limited by soil P and herbaceous P by soil N. The analysis of nutrient correlations between shrubs, herbs, and trees showed a partial positive correlation between understory plants and tree leaf nutrients, indicating relatively weak competition among different plant groups. Furthermore, in P. amurense plantations, the P content in understory herbs was significantly positively correlated with soil P, suggesting that low soil phosphorus limits tree growth in this area. No significant correlation between soil and leaf nutrients was found in Q. mongolica plantations. In contrast, in F. mandshurica plantations, soil C and N were significantly positively correlated with tree leaf C, and understory shrub P and herb P were positively correlated with soil P, suggesting that leaf C absorption is constrained by soil C and N. Overall, this study highlights the nutrient competition between understory vegetation and tree layers, with all species showing a negative correlation between understory vegetation and tree nutrients, indicating nutrient competition. These findings provide valuable insights into the ecological dynamics of urban forests and offer guidance for optimizing urban forest management strategies. Full article

Microbial inoculants are vital for promoting plant growth and facilitating the ecological restoration of degraded forested regions near abandoned mine sites. However, the direct application of liquid microbial inoculants is often challenging due to low microbial activities and poor transport efficiencies, which limit their effectiveness in complex soil environments. To tackle these challenges, this study utilized immobilized microbial technology to evaluate the effectiveness of solid microbial inoculants sourced from peat (P), biochar (BC), and spent mushroom substrates (SMSs) in enhancing the soil’s multifunctionality and promoting plant growth. Specifically, this research sought to assess the effectiveness of solid microbial inoculants derived from peat (P), biochar (B), and spent mushroom substrates (SMSs) in enhancing soil multifunctionality and promoting plant growth in nutrient-deficient soils that were affected by abandoned mine sites. We aimed to evaluate the performance of different solid microbial inoculants in improving the soil’s nutrient content and enzyme activities. A 24-week pot experiment was conducted using Medicago sativa L. in nutrient-poor soil. The results demonstrated that, in contrast to peat and biochar, SMSs effectively interacted with microbial inoculants and significantly improved the nutrient content and enzyme activities of nutrient-deficient soil. It was noted that β-1,4-glucosidase (BG), invertase, β-1,4-N-acetylglucosaminidase (NAG), urease, and soil available phosphorus increased by 204%, 405%, 118%, 198%, and 297%, respectively. The soil’s multifunctionality improved by 320% compared with the CK, and the plant biomass also increased significantly. Further, our random forest analysis indicated that the soil available phosphorus, ammonium nitrogen, total nitrogen, total carbon content, arylsulfatase, pH, total phosphorus, NAG, and BG were key environmental factors that induced changes in plant biomass. These findings highlighted the potential of SMSs as an effective carrier for immobilized microbial inoculants, which provides a sustainable approach for the restoration of forest soils surrounding abandoned mine sites, as well as a promising avenue for the valorization of agricultural waste. Full article