Search Results (513)

The combined challenges of water scarcity and inefficient nitrogen use pose substantial barriers to sustainable agricultural development. Optimizing the coordinated regulation of water and nitrogen resources in fruit trees is essential for promoting water-saving agriculture in drylands. To establish a water and nitrogen collaborative management model for efficient resource utilization, this study conducted a 3-year field experiment examining different irrigation amount (W1: 4500 m³·ha⁻¹, W2: 6000 m³·ha⁻¹, and W3: 7500 m³·ha⁻¹) and nitrogen application rates (N1: 200 kg·ha⁻¹, N2: 300 kg·ha⁻¹, and N3: 400 kg·ha⁻¹), coupled with ¹⁵N isotopic labeling, to evaluate the impact of water and nitrogen regulation on the following: (i) the spatial distribution patterns of water and nitrogen in the root zone soil, (ii) dynamic characteristics of water and nitrogen across organs, and (iii) ¹⁵N absorption and utilization. The findings revealed that 20–80 cm depth was the key zone for water and nitrogen absorption by roots of pear. The W2 treatment met the optimal irrigation requirement for young pear tree roots and exhibited the optimal dynamic characteristics of water and nitrogen among the newly formed organs. At the end of the growth period, N3 treatment had the highest nitrogen content and the root system was the main organ for nitrogen absorption and storage. Water-saving irrigation coupled with optimized nitrogen application synergistically enhanced the nitrogen accumulation efficiency in fragrant pear. The W2N2 treatment exhibited the highest ¹⁵N absorption and utilization rate (40.79%), effectively promoting nitrogen absorption and assimilation, reducing nitrogen losses, and offering valuable insights for advancing sustainable practices in the fruit and forestry industries. Full article

In recent years, the rapid development of commercial satellite projects, such as low-Earth orbit (LEO) communication and remote sensing constellations, has driven the satellite industry toward low-cost, rapid development, and large-scale deployment. Commercial off-the-shelf (COTS) components have been widely adopted across various commercial satellite platforms due to their advantages of low cost, high performance, and plug-and-play availability. However, the space environment is complex and hostile. COTS components were not originally designed for such conditions, and they often lack systematically flight-verified protective frameworks, making their reliability issues a core bottleneck limiting their extensive application in critical missions. This paper focuses on COTS solid-state drives (SSDs) onboard the Jilin-1 KF satellite and presents a full-lifecycle reliability practice covering component selection, system design, on-orbit operation, and failure feedback. The core contribution lies in proposing a full-lifecycle methodology that integrates proactive design—including multi-module redundancy architecture and targeted environmental stress screening—with on-orbit data monitoring and failure cause analysis. Through fault tree analysis, on-orbit data mining, and statistical analysis, it was found that SSD failures show a significant correlation with high-energy particle radiation in the South Atlantic Anomaly region. Building on this key spatial correlation, the on-orbit failure mode was successfully reproduced via proton irradiation experiments, confirming the mechanism of radiation-induced SSD damage and providing a basis for subsequent model development and management decisions. The study demonstrates that although individual COTS SSDs exhibit a certain failure rate, reasonable design, protection, and testing can enhance the on-orbit survivability of storage systems using COTS components. More broadly, by providing a validated closed-loop paradigm—encompassing design, flight verification and feedback, and iterative improvement—we enable the reliable use of COTS components in future cost-sensitive, high-performance satellite missions, adopting system-level solutions to balance cost and reliability without being confined to expensive radiation-hardened products. Full article

Sloping cropland on the Loess Plateau faces severe challenges from soil organic carbon (SOC) depletion and structural instability due to erosion and intensive tillage. Although mulching can enhance SOC sequestration, its long-term effects on the spatial distribution of SOC and aggregates across slopes remain unclear. A 15-year field experiment evaluated five practices—conventional tillage (T), no tillage (NT), straw mulching (SM), plastic film mulching (PM), and ridge–furrow plastic film mulching (RPM)—on SOC storage, aggregate stability, and their variation with different slope positions. Compared to T, all mulching treatments significantly increased SOC concentration by 4.19% to 83.48% in the 0–30 cm layer. SM and RPM notably increased macro-aggregates (>2 mm) and their associated SOC (24.04–56.49% higher than T) by adding organic matter and optimizing micro-topography. Different slope positions strongly influenced SOC redistribution: lower slopes accumulated more SOC than upper slopes due to erosion–deposition processes. Mulching reduced SOC spatial variability and minimized differences between slope positions. Although mulching increased cumulative SOC mineralization compared to T, the long-term net SOC gain was positive, driven by improved aggregate protection and reduced erosion. SM and RPM are recommended for sustainable slope farmland management due to their dual benefits in enhancing carbon sinks and soil stability. This study offers practical strategies for improving soil health and SOC sequestration in vulnerable sloping landscapes. Full article

Long-term human cultivation activities are the key factors of the vertical distribution and storage dynamics of soil organic carbon (SOC) in cropland. Based on a 45-year long-term field experiment, this study systematically compared SOC dynamics and carbon storage characteristics in soil profiles (0–200 cm) between cultivated land and adjacent natural forest. The findings reveal the hierarchical regulatory effects of tillage management on the soil carbon pool. The results show that: (1) Under both land use types, SOC content decreased exponentially with depth, but values in cultivated soils were 0.35–1.54% lower than in forest soils at each layer. SOC content in surface soil (0–78 cm) was significantly higher than in the subsoil (78–158 cm) and substratum layers (158–200 cm) (p < 0.01). At equivalent depths, SOC in cultivated land was significantly lower than in forest land (p < 0.01). Over 45 years, the SOC accumulation rate in the surface soil of cropland (0.07 g·kg⁻¹·yr⁻¹) was only half that of forest land (0.14 g·kg⁻¹·yr⁻¹). (2) The controls of soil physicochemical properties on SOC differed with land use: in forest soils, SOC correlated positively with clay content (r = 0.63, p < 0.01), whereas in cultivated soils, SOC was primarily regulated by total nitrogen (r = 0.94, p < 0.01) and sand content (r = 0.60, p < 0.01) and negatively correlated with bulk density (r = −0.55, p < 0.01) and pH value (r = −0.45, p < 0.05). (3) Long-term tillage significantly reshaped soil profile structure, thickening the plough layer from 20 cm to 78 cm. Surface carbon storage reached 20.76 t·ha⁻², an increase of 11.13 t·ha⁻² compared with forest soil (p < 0.01). However, storage decreased by 4.99 t·ha⁻² and 7.60 t·ha⁻² in the subsoil and substratum layers, respectively (p < 0.01). The SOC storage increment rate was 50.95 t·ha⁻²·yr⁻¹ higher than that of forest soil in the surface layer but 46.81 t·ha⁻²·yr⁻¹ and 11.12 t·ha⁻²·yr⁻¹ lower in deeper layers. These results confirm that cultivation alters soil structure and material cycling, enhancing carbon enrichment in surface soils while accelerating depletion of deeper carbon pools. This provides new insights into the vertical differentiation mechanisms of SOC under long-term agricultural management. Full article

This study investigates the impact of biochar derived from red pepper by-products on crop growth, soil carbon storage, and agricultural productivity, with a focus on adapting red pepper cultivation to climate change. The experiment was conducted over two years at the Chungcheongnam-do Agricultural Research and Extension Services in South Korea. Biochar was applied at varying rates based on its carbon content (0.0, 2.5, 5.0, 10.0 Mg C ha⁻¹) to evaluate its effects on soil properties and red pepper yield. The biochar, produced using a Top-Lit Updraft (TLUD) gasification system, possessed a carbon content of 68.7% and a high pH of 10.3. The results demonstrated that biochar application significantly enhanced red pepper growth and yield, with the highest total yield observed at the maximum application rate (BC_10.0, 10.0 Mg C ha⁻¹). However, yield efficiency (yield increase per Mg of biochar C) was highest at the lowest application rate (BC_2.5, 2.5 Mg C ha⁻¹). Soil analysis revealed that biochar amendment improved soil pH, electrical conductivity (EC), and total carbon content. Although the standard soil analysis protocol (<2 mm sieving) resulted in an underestimation of soil carbon stock by excluding coarse biochar particles, the persistence of these coarse fractions confirms the high physical stability of the biochar, validating its potential as a long-term carbon sink. These findings provide a scientific basis for optimized biochar application strategies that balance productivity with carbon sequestration. Full article

The large-scale development of mineral resources has led to a sharp increase in the amount of tailings and waste rock accumulated in tailings ponds and waste disposal sites, forming a large number of high-risk tailings dams and high-pile waste disposal sites. In recent years, frequent incidents of tailings dam breaches and landslides in high-pile dumping sites have posed a serious threat to the lives and property of downstream residential areas. Therefore, studying the collaborative storage technology of waste rock and tailings is of great significance. By conducting physical model experiments on tailings dams of a similar scale and using the SEEP/W module in GeoStudio 2022.1 software for numerical simulation, the influence of the built-in waste-rock inclusions on the permeability characteristics of the dam body and the depth of the saturation line is analyzed. The results showed that the seepage flow increased with the decrease in fine particle content in the waste-rock inclusions, with the highest seepage flow in the C-grade waste-rock inclusions and the most significant decrease in the saturation line, and the seepage volume decreased with the increase in the spacing between waste-rock inclusions. The depth of the saturation line is negatively correlated with the distance between the centers of the waste-rock inclusions; that is, the smaller the distance (200 mm), the greater the depth of the saturation line. The research results can provide a reference for ensuring the safety and stability analysis of tailings dams. Full article

This study aimed to address the limited infiltration capacity of the double ridge–furrow mulching system (DRFM) under heavy rainfall on the Loess Plateau, which exacerbates surface runoff and mid-summer soil water deficits in semi-arid rainfed areas. By incorporating infiltration holes to optimize the system, we evaluated their effects on soil water storage, maize growth, and water use efficiency (WUE). A two-year field experiment (2021–2022) comprised four treatments: conventional flat planting (CK), the traditional ridge-furrow system (CWC), the double ridge-furrow system (DWC), and the double ridge-furrow system with infiltration holes (DWCR). The experimental periods represented a normal precipitation year (2021, 410 mm) and a dry year (2022, 270 mm). Results indicated that the DWCR treatment established preferential flow pathways, significantly enhancing deep soil water storage and its utilization efficiency during critical phenological stages, particularly under drought. This improved deep water accelerated crop growth and boosted yield. Compared to the CK, CWC, and DWC treatments, the DWCR treatment significantly increased plant height, aboveground dry matter (ADM), yield, and WUE. Specifically, the DWCR treatment improved yield and WUE by 0.24–20.04% and 2.75–26.27%, respectively. In the dry year, the yield of the DWC treatment increased by 12.72% compared to its yield in the normal year, whereas the DWCR treatment achieved a greater increase of 19.18%. Root analysis confirmed that the DWCR treatment significantly increased root weight density in the 20–60 cm soil layer under drought, optimizing root spatial distribution and thereby enhancing deep water uptake and drought resistance. In conclusion, incorporating infiltration holes into the DRFM is an effective strategy for optimizing soil water distribution, improving crop drought tolerance and WUE, and promoting sustainable semi-arid rainfed agriculture. Full article

Background: The use of pesticides among smallholder farmers, agrochemical sellers, and agricultural officers involves a complex interplay of knowledge, economic factors, and regulatory frameworks. Therefore, this study explores the patterns, practices, and socio-environmental dynamics of pesticide use among smallholder farmers and agro-input sellers in Iringa and Njombe. Method: This study employed a qualitative, phenomenological design, guided by the socio-ecological model (SEM), to explore the lived experience of farmers, agro-dealers, and extension officers. It involved a total of 23 interviews performed in the Njombe and Iringa regions. Data were collected between October 2024 and March 2025, using a combination of in-depth phenomenological interviews, key informant interviews, and field observations, and were categorized into themes and subthemes analyzed using InVivo. Results: The study involved a total of 23 participants drawn from the Iringa and Njombe regions. The gender distribution was nearly balanced, with 52.1% male and 47.8% female respondents. The mean age of participants was 33 years (95% CI: 29.3–37.3). In terms of education, over half (52.17%) had completed primary school. The findings show that smallholders in Iringa and Njombe widely use mixed pesticides and fertilizers, rely on trusted brands, and adapt to climate impacts, but face challenges with regard to unsafe mixing, poor storage, fake products, and weak regulation, highlighting the need for better education, market oversight, and safer practices. Conclusion: Using the socio-ecological model, the findings indicate that pesticide use among smallholder horticultural farmers in Iringa and Njombe is influenced by a complex interaction of socio-economic constraints, market forces, climate variability, and institutional shortcomings. Although farmers have some awareness of safe practices, systemic barriers continue to limit the adoption of sustainable pesticide management. Full article

Terrestrial water storage includes soil water storage, groundwater storage, surface water storage, snow water equivalent, plant canopy water storage, biological water storage, etc., which can comprehensively reflect the total change in water volume during processes such as precipitation, evapotranspiration, runoff, and human water use in the basin hydrological cycle. The Gravity Recovery and Climate Experiment (GRACE) satellite provides a powerful tool and a new approach for observing changes in terrestrial water storage and groundwater storage. The North China Plain (NCP) is a major agricultural region in the northern arid area of China, and long-term overexploitation of groundwater has led to increasingly prominent ecological vulnerability issues. This study uses GRACE and Global Land Data Assimilation System (GLDAS) hydrological model data to assess the spatiotemporal patterns of groundwater drought in the NCP and its various sub-regions from 2003 to 2022, identify the locations, occurrence probabilities, and confidence intervals of seasonal and trend mutation points, quantify the complex interactive effects of multiple climate factors on groundwater drought, and reveal the propagation time from groundwater drought to agricultural drought. The results show that: (1) from 2003 to 2022, the linear tendency rate of groundwater drought index (GDI) was −0.035 per 10 years, indicating that groundwater drought showed a gradually worsening trend during the study period; (2) on an annual scale, the most severe groundwater drought occurred in 2021 (GDI = −1.59). In that year, the monthly average GDI in the NCP ranged from −0.58 to −2.78, and the groundwater drought was most severe in July (GDI = −2.02); (3) based on partial wavelet coherence, the best univariate, bivariate for groundwater drought were soil moisture (PASC = 19.13%); and (4) in Beijing, Tianjin and Hebei, the propagation time was mainly concentrated in 1–5 months, with average lag times of 2.87, 3.20, and 2.92 months, respectively. This study can not only reduce and mitigate the harm of groundwater drought to agricultural production, social life, and ecosystems by monitoring changes in groundwater storage, but also provide a reference for the quantitative identification of the dominant factors of groundwater drought. Full article

This study evaluates the impact of applying biochar alongside nitrogen fertilizer on soil aggregates and aggregate-associated carbon through a two-year experiment under irrigated conditions in North Xinjiang. In 2021, a randomized block design established 36 experimental plots. The experiment employed a factorial design with three levels of nitrogen fertilizer and four levels of biochar. Measurements of soil aggregates and aggregate-associated organic carbon were taken in 2022. This study’s objectives were to quantify biochar’s effect on soil aggregation and stability and to determine the distribution of SOC across different aggregate sizes. The results indicated that macroaggregates (>2 mm and 0.25–2 mm) were most common (N2B1, N2B2, and N2B3), making up 75.57–78.46% of all aggregates. In treatments with reduced nitrogen and biochar (N2B1, N2B2, and N2B3), soil aggregate refractory organic carbon content was significantly higher compared to other treatments. Generally, applying reduced nitrogen with moderate biochar (N2B2) significantly increased soil organic carbon and refractory organic carbon levels, aiding carbon fixation and improving soil carbon storage. Thus, biochar application effectively enhances carbon storage in agricultural soils, offering valuable insights for improving soil fertility in irrigated regions of northern Xinjiang. Full article

Cytokinin- and Auxin-Based Plant Growth Regulators (PGRs) are commonly employed to increase fruit size due to their ability to modulate cellular structure. This study aimed to evaluate the effects of different PGR application protocols on histological parameters, yield components, and fruit quality in ‘Maxi Gala’ apple. The experiments were carried out under humid subtropical conditions of southern Brazil across two growing seasons (2021/22 and 2022/23), allowing comparison of treatment performance under distinct climatic patterns. Data from common treatments were combined across years for integrated analysis. The PGRs used included 6-benzyladenine (BA) as a cytokinin source; naphthalene acetic acid (NAA) as an auxin source; and tryptophan, a precursor of auxin biosynthesis. PGRs were applied in various combinations and concentrations between 10 days after dormancy break (BBCH 01) and fruit diameters of 25–27 mm (BBCH 74), following a randomized block design with four replicates of twelve trees each. The multivariate analysis of treatments was performed using Principal Component Analysis (PCA). Additionally, an analysis of variance was performed for flesh firmness loss, with means compared using Tukey’s test (p < 0.05). PGRs significantly influenced only the histological parameters of the fruit flesh tissues. BA and tryptophan had the greatest effects on cell size and cell number in the fruit flesh, respectively, both reducing intercellular spaces. Tryptophan was associated with a higher number of smaller cells, whereas NAA promoted larger cell sizes. The combination of BA and NAA, as well as a single application of BA at petal fall, resulted in the highest yield performances and increased the proportion of large fruits. Furthermore, BA enhanced the percentage of red skin coloration and improved flesh firmness during storage. Full article

Understanding the impact of climate change and altered hydrologic cycles on regional water storage trends is crucial for predicting changes in recharge and streamflow and informing decisions regarding drought resilience and flood mitigation. While many regions have become drier under global climate change, the northeast United States has experienced an increased precipitation intensity, driving groundwater rise. This study integrates terrestrial water storage data from NASA’s Gravity Recovery and Climate Experiment (GRACE) satellites and soil moisture data from Soil Moisture Active Passive (SMAP), as well as long-term instrumental groundwater records from USGS groundwater monitoring wells, to understand the nature of storage trends. The results show that while aquifer-wide groundwater storage anomalies have stabilized in recent years, shallow groundwater and certain surface water bodies have accumulated about 0.6 cm of water annually, adding over 10 cm to the landscape, since 2005. These findings indicate that excess water from heavy rainfall is mainly stored in the shallow subsurface as perched aquifers and temporary wetlands rather than deep (5–30 m) aquifers. Understanding this change in storage is crucial for improving water resource management and adapting more effectively to a changing climate in the region. Full article

This study presents a scenario analysis of Kazakhstan’s electricity market using the PyPSA-KZ model, with a focus on the integration of renewable energy sources (RES). As Kazakhstan transitions towards a low-carbon economy, this study evaluates the technical and economic implications of increasing RES penetration under various scenarios, ranging from 10% to 60% RES shares, with projections targeted for the year 2030. The study simulates system behavior across scenarios and analyzes key indicators, including total system cost, electricity tariff, generation mix, thermal ramping, and CO₂ emissions. Results indicate that up to 30% RES integration is feasible without significant structural changes, delivering reduced system costs and emissions. However, scenarios beyond 30% reveal growing flexibility challenges, necessitating investment in grid modernization, energy storage, and flexible backup capacity. The model outcomes are benchmarked against the International Energy Agency’s 2030 carbon neutrality scenarios and show strong alignment, particularly at 45% RES share. Comparative insights are also drawn from international experiences in Denmark and China. This research demonstrates that the PyPSA-KZ model is a powerful tool for planning Kazakhstan’s energy transition and offers data-driven recommendations to support national energy security and climate goals. Full article

Accurate forecasts of the U.S. renewable energy consumption mix are essential for planning transmission upgrades, sizing storage, and setting balancing market rules. We introduce a Bayesian Dirichlet ARMA model (BDARMA) tailored to monthly shares of hydro, geothermal, solar, wind, wood, municipal waste, and biofuels from January 2010 through January 2025. The mean vector is modeled with a parsimonious VAR(2) in additive log ratio space, while the Dirichlet concentration parameter follows an intercept plus five Fourier harmonics, allowing for seasonal widening and narrowing of predictive dispersion. Forecast performance is assessed with a 61-split rolling origin experiment that issues twelve month density forecasts from January 2019 to January 2024. Compared with three alternatives (a Gaussian VAR(2) fitted in transform space, a seasonal naive approach that repeats last year’s proportions, and a drift-free ALR random walk), BDARMA lowers the mean continuous ranked probability score by 15 to 60 percent, achieves componentwise 90 percent interval coverage near nominal, and maintains point accuracy (Aitchison RMSE) on par with the Gaussian VAR through eight months and within 0.02 units afterward. These results highlight BDARMA’s ability to deliver sharp and well-calibrated probabilistic forecasts for multivariate renewable energy shares without sacrificing point precision. Full article

The aim of this study was to find a way to remove persistent bacteria inhabiting in vitro shoot cultures of raspberry. Often, decontamination treatments fail to reach bacteria residing in internal tissues, leading to contaminated cultures later. Three raspberry cultivars, each harboring a unique bacterial contaminant, were used in this study. Experiments were conducted to assess the potential for eliminating these bacteria using biocide infiltration at 30 mbar. The following biocides were used: mercuric chloride (HgCl₂ at 0.05 and 0.1%), Plant Preservative Mixture (PPM^TM 0.2–4%), rifampicin (50–200 mg L⁻¹), and sodium hypochlorite (NaOCl 0.1–60%). Only 0.05 or 0.1% HgCl₂ applied via infiltration successfully eliminated all of the bacteria from the shoots, which remained bacteria-free for several years, as confirmed by indexing explants on bacterial media at each subculture. While most treated shoots became necrotic and died due to infiltration, the surviving shoots remained vital and provided bacteria-free material for long-term propagation. Results from experiments comparing micropropagation potential in bacteria-contaminated and bacteria-free cultures showed that bacteria-free shoots produced longer shoots, and the total number of shoots did not differ, except for ‘Norna’/Curtobacbacteria-free cultures, which were more productive. Bacteria-contaminated shoots rooted at higher percentages, but roots were much shorter, and plantlets initiated growth during acclimatization later. Cultures that were contaminated did not survive storage at 4 °C in the dark for 4–6 months. Full article