Search Results (139)

Soil organic nitrogen (SON) positively influences crop productivity, greenhouse gas (GHG) emissions, and sustained nitrogen (N) supply. Herein, we observed the effect of different treatments; no fertilizers (CK), chemical fertilizers (nitrogen, phosphorus, and potassium (NPK)), organic manure, and NPK + OM (NPKOM). This study was performed in a randomized complete block design (RCBD) with three replications. The results indicated that NPKOM treatment significantly decreased the nitrous oxide (N₂O) emissions by 19.97% and 17.47% compared to NPK in both years. This was linked with improved soil nutrient availability, soil organic carbon, soil organic nitrogen (SON) storage (10.06% and 12.38%), SON sequestration (150% and 140%), increased soil particulate (44.11% and 44%), and mineral-associated organic N (26.98% and 26.47%) availability. Furthermore, NPKOM also enhanced nitrate reductase (NR: 130% and 112%), glutamine synthetase (GS: 93% and 88%), sucrose phosphate synthase (SPS: 79% and 98%), SSs (synthetic direction; 57% and 50%), and decreased SSs activity in the decomposition direction (18% and 21%). This, in turn, inhibited the decomposition of sucrase and enhanced starch conversion into carbohydrates, thus leading to an increase in rice yield and a decrease in N₂O emissions. All fertilizations, particularly NPKOM, significantly enhanced grain protein contents by increasing N uptake and its availability. Therefore, NPKOM is an effective practice to enhance rice productivity, and SON sequestration and mitigate the N₂O emissions and subsequent climate change. Full article

This study investigates the mechanisms by which green finance mitigates non-point source pollution. Based on provincial panel data from China spanning 2005 to 2023, this study conducts an empirical analysis that yields several key findings: (1) The development of green finance significantly reduces the intensity of agricultural non-point source pollution. (2) Green finance indirectly contributes to pollution reduction by incentivizing farmers to adopt environmentally sustainable production practices. (3) The pollution control effects of green finance are amplified in regions with advanced digital infrastructure. (4) The impact of green finance on agricultural pollution demonstrates a threshold effect associated with regional innovation capacity—only when innovation capability exceeds a certain threshold does the emission reduction effect of green finance become evident. Theoretically, this study broadens the research dimensions of green finance by integrating farmer behavioral factors and revealing boundary conditions related to technology and innovation. Policy implications include the need to tailor green financial products for agriculture, accelerate the development of rural digital infrastructure, and implement innovation-driven differentiated policies to enhance precision. Full article

This study aimed to analyse the spatiotemporal evolution of phytoplankton community dynamics and its underlying mechanisms in the Liaoning section of the Liao River Basin in 2010, 2015, and 2020. Phytoplankton species diversity increased significantly, with an increase from three phyla and 31 species in 2010 to six phyla and 74 species in 2020. Concurrent increases in α-diversity indicated continuous improvements in habitat heterogeneity. The community structure shifted from a diatom-dominated assemblage to a green algae–diatom co-dominated configuration, contributing to an enhanced water purification capacity. The upstream agricultural zone (Tieling section) had elevated biomass and low diversity, indicating persistent non-point-source pollution stress. The midstream urban–industrial zone (Shenyang–Anshan section) emerged as a phytoplankton diversity hotspot, likely due to expanding niche availability in response to point-source pollution control. The downstream wetland zone (Panjin section) exhibited significant biomass decline and delayed diversity recovery, shaped by the dual pressures of resource competition and habitat filtering. The driving mechanism of community succession shifted from nutrient-dominated factors (NH₃-N, TN) to redox-sensitive factors (DO, pH). These findings support a ‘zoned–graded–staged’ ecological restoration strategy for the Liao River Basin and inform the use of phytoplankton as bioindicators in watershed monitoring networks. Full article

While significant progress has been made in controlling point source pollution, agricultural non-point source pollution (AGNPSP) has emerged as a major contributor to global water pollution, posing a severe threat to ecological quality. According to China’s Second National Pollution Source Census, AGNPSP constitutes a substantial proportion of water pollution, making its mitigation a critical challenge. Identifying AGNPSP risk zones is essential for targeted management and effective intervention. This study focuses on Yongchuan District, a representative hilly–mountainous area in the Yangtze River Basin. Applying the landscape ecology “source–sink” theory, we selected seven natural factors influencing AGNPSP and constructed a minimum cumulative resistance model using remote sensing post-processing data. An attempt was made to classify the “source” and “sink” landscapes, and ultimately conduct a risk assessment of AGNPSP in Yongchuan District, identifying the key areas for AGNPSP control. Key findings include: 1. Vegetation coverage is the most significant natural factor affecting AGNPSP. 2. Extremely high- and high-risk zones cover 90% of Yongchuan, primarily concentrated in the central and southern regions, indicating severe AGNPSP pressure that demands urgent management. 3. The levels of ammonia nitrogen and total phosphorus in the typical sections are related to the risk levels of the corresponding sections. Consequently, the risk level of AGNPSP directly correlates with the pollutant concentrations measured in the sections. This study provides a robust scientific basis for AGNPSP risk assessment and targeted control strategies, offering valuable insights for pollution management in Yongchuan and similar regions. Full article

Excessive nitrogen accumulation from aquaculture poses a significant threat to water quality in river–lake systems. This study investigated the Taipu River and five interconnected lakes to analyze the forms, spatial distribution, and ecological impact of nitrogen in both water and surface sediments. Sediment total nitrogen (TN), ammonium nitrogen (NH₄⁺-N), and nitrate nitrogen (NO₃⁻-N) were measured, with aquaculture-dominated lakes such as Xueluoyang Lake and Caodang Marsh exhibiting significantly higher sedimentary TN concentrations than the Taipu River. In Xueluoyang Lake, the average TN content reached 1037.3 mg/kg—1.87 times higher than in the river—highlighting the legacy effect of historical intensive aquaculture. Correlation analyses showed strong associations between sediment NH₄⁺-N and NO₃⁻-N and nitrogen levels in overlying water, confirming sediments as a major endogenous nitrogen source. Multivariate statistical methods, including Pearson’s correlation, hierarchical clustering, and principal component analysis, were applied to elucidate spatial patterns and key influencing factors. Water quality evaluation indices and sediment organic pollution assessments revealed widespread TN exceedance, particularly in dry seasons, with water quality deteriorating to Class V or worse. These results underscore the need for strengthened control of sedimentary nitrogen release and effective management of agricultural non-point source pollution to restore and protect water quality in river–lake systems. Full article

Agricultural producers play a crucial role in combating agricultural non-point source pollution, so improving their production behaviors and practices will be key to alleviating such pollution. This study employs the Theory of Planned Behavior and focuses on Huaxian County, a major grain-producing county in Anyang City, Henan Province. The study focuses on randomly selected sample farming households in townships within Hua County’s agricultural intensification zone. Through structural equation modeling, it has analyzed the impact of farmers’ individual characteristics, behavioral attitudes, subjective norms, and perceived behavioral control on their willingness to engage in pollution management, as well as the influence of such willingness on actual management behaviors. Research indicates that behavioral attitudes, subjective norms, and perceived behavioral control significantly and positively influence governance intention, and governance intention significantly and positively influences governance behavior. Behavioral attitude is the key latent variable (behavioral attitude > perceived behavioral control > subjective norm). That is, the economic benefits derived from agricultural non-point source pollution governance constitute the most critical factor influencing farmers’ willingness to participate in pollution governance. Furthermore, farmers’ willingness to participate in pollution control bridges the gap between their attitudinal inclination and actual behavioral implementation. Accordingly, this study can provide a theoretical basis and reference for the governance of non-point source pollution in county-level regions of Henan Province and similar major grain-producing areas and offer theoretical support for the sustainable development of agriculture. Full article

Understanding the impact of climate change on agricultural nonpoint source (NPS) pollution is crucial for developing effective adaptation strategies and reducing vulnerabilities where such challenges exist. This study evaluated the impact of precipitation and temperature variations on Total Inorganic Nitrogen (TIN), Total Inorganic Phosphorus (TIP), and sediment loads in the Sand River Catchment (SRC) using the Soil and Water Assessment Tool plus (SWAT+). One-way analysis of variance (ANOVA) was used to determine the significance (p < 0.05) of the relationships (R²) between precipitation and temperature on sediment, TIN, and TIP loads in the SRC. SWAT+ calibration and validation demonstrated that the statistical indices (NSE and R² ≥ 0.72; −17.30 ≤ PBIAS ≤ 14.74) fell within an acceptable range. Results indicated a significant influence of average monthly precipitation (p < 0.0001) and temperature (p ≤ 0.004) on sediment, TIN, and TIP loads. In addition, a decrease in average annual precipitation led to a decline in sediment, TIN, and TIP loads (R² ≥ 0.55), with the average annual temperature increasing in the same period (R² ≤ 0.23). This study confirms that climate change contributes to agricultural NPS pollution in the SRC and highlights the need to employ suitable adaptation strategies for pollution control in the catchment. Full article

The Soil and Water Assessment Tool (SWAT) was utilized to analyze the spatiotemporal distribution patterns of composite non-point source pollution in the Yapu Port Basin, China, and to quantify the pollutant load contributions from various sources. Scenario-based simulations were designed to assess the effectiveness of different mitigation strategies, focusing on both agricultural and urban non-point source pollution control. The watershed was divided into 39 sub-watersheds and 106 hydrologic response units (HRUs). Model calibration and validation were conducted using the observed data on runoff, total phosphorus (TP), and total nitrogen (TN). The results demonstrate good model performance, with coefficients of determination (R²) ≥ 0.85 and Nash–Sutcliffe efficiencies (NSEs) ≥ 0.84, indicating its applicability to the study area. Temporally, pollutant loads exhibited a positive correlation with precipitation, with peak values observed during the annual flood season. Spatially, pollution intensity increased from upstream to downstream, with the western region of the watershed showing higher loss intensity. Pollution was predominantly concentrated in the downstream region. Based on the composite source analysis, a series of management measures were designed targeting both agricultural and urban non-point source pollution. Among individual measures, fertilizer reduction in agricultural fields and the establishment of vegetative buffer strips demonstrated the highest effectiveness. Combined management strategies significantly enhanced pollution control, with average TN and TP load reductions of 22.18% and 22.70%, respectively. The most effective scenario combined fertilizer reduction, improved urban stormwater utilization, vegetative buffer strips, and grassed swales in both farmland and orchards, resulting in TN and TP reductions of 67.2% and 56.2%, respectively. Full article

Non-point source (NPS) pollution from agriculture accounts for more than 20% of the total pollution load in the Republic of Korea, with the highest nutrient balance among OECD countries. Rice paddy fields are among the most important NPSs because of their large area, intensive fertilizer use, intensive use of irrigation water, and subsequent drainage. Therefore, the use of controlled drainage in paddy fields (Test) was evaluated for reduction in the discharged volumes and pollutant loads in drainage and stormwater runoff in comparison to plots using traditional drainages (Control). The results show that the loads were highly variable and that the reductions in the annual load of biochemical oxygen demand (BOD), suspended solid (SS), total nitrogen (T-N), total phosphorus (T-P), and total organic carbon (TOC) in the Test compared to that of the Control were 31.0 ± 28.9%, 83.5 ± 11.8%, 65.4 ± 12.2%, 69.1 ± 21.7%, and 64.9 ± 12.9%, respectively. It was shown that discharge in the post-harrowing and transplanting drainage (HD) was predominantly responsible for the total loads; therefore, the load reduction in HD was evaluated further at additional sites. The reduction at all studied sites was highly variable and as follows: 30.0 ± 33.6%, 70.9 ± 24.6%, 32.2 ± 45.5%, 45.7 ± 37.0%, and 27.0 ± 71.5%, for BOD, SS, T-N, T-P, and TOC, respectively. It was also demonstrated that controlled drainage contributed significantly to reducing the loads and volume of stormwater runoff from paddy fields. Correlations between paddy field conditions and multiple regression showed that the loads were significantly related to paddy water quality. The results of this study strongly suggest that controlled drainage is an excellent alternative for reducing the discharge of NPS pollutants from paddy fields. It is also suggested that the best discharge control would be achieved by combinations of various discharge mitigation alternatives, such as the management of irrigation, drainage, and fertilization, as well as drainage treatment, supported by more field tests, identification of the fates of pollutants, effects of rainfall, and climate changes. Full article

The Yellow River Basin in China is the region with the most severe agricultural non-point source pollution. The control of agricultural non-point source pollution is an important task for ecological protection and high-quality development in the Yellow River Basin at present and in the near future. This paper takes the eight provinces located along the Yellow River, except Sichuan, as the research object. This study estimates the total amount, intensity, and structure of agricultural non-point source pollution from 2014 to 2023 by adopting quantitative methods such as the pollutant discharge coefficient method, the equivalent pollution load method, and so on. The results reveal that the total amount of non-point source pollution of the Yellow River Basin has risen from approx. 4.94 million tons in 2014 to approx. 7.45 million tons in 2023. However, the growth rate has decelerated over the past five years, and the pollution intensity has decreased by 15~40% on average. The characteristics of agricultural non-point source pollution presents as follows: chemical oxygen demand (COD) emissions have become the most significant pollutant, accounting for 90% of the total pollution; livestock and poultry breeding has become the main source of pollution; and the key areas of pollution have shifted from the lower reaches to the middle and upper reaches, but the regional differences have been narrowing, as measured by the Gini coefficient. An analysis of the Kuznets curve indicates that most of the provinces in the Yellow River Basin still depend on an extensive growth model characterized by high input, high emission, and low output. Finally, this paper proposes a classified governance and measurement system for regions and sources, aiming to enhance the agricultural non-point source pollution prevention and control system. It also advocates for accelerating the green transformation of agricultural production in the Yellow River Basin to achieve the rapid decoupling of pollution emission from economic growth. Full article

In recent years, frequent open biomass burning (OBB) activities such as agricultural residue burning and forest fires have led to severe air pollution and carbon emissions across South and Southeast Asia (SSEA). We selected this area as our study area and divided it into two sub-regions based on climate characteristics and geographical location: the South Asian Subcontinent (SEAS), which includes India, Laos, Thailand, Cambodia, etc., and Equatorial Asia (EQAS), which includes Indonesia, Malaysia, etc. However, existing methods—primarily emission inventories relying on burned area, fuel load, and emission factors—often lack accuracy and temporal resolution for capturing fire dynamics. Therefore, in this study, we employed high-resolution fire point data from China’s Feng Yun-4A (FY-4A) geostationary satellite and the Fire Radiative Power (FRP) method to construct a daily OBB emission inventory at a 5 km resolution in this region for 2020–2022. The results show that the average annual emissions of carbon (C), carbon dioxide (CO₂), carbon monoxide (CO), methane (CH₄), non-methane organic gases (NMOGs), hydrogen (H₂), nitrogen oxide (NO_X), sulfur dioxide (SO₂), fine particulate matter (PM_2.5), total particulate matter (TPM), total particulate carbon (TPC), organic carbon (OC), black carbon (BC), ammonia (NH₃), nitric oxide (NO), nitrogen dioxide (NO₂), non-methane hydrocarbons (NMHCs), and particulate matter ≤ 10 μm (PM₁₀) are 178.39, 598.10, 33.11, 1.44, 4.77, 0.81, 1.02, 0.28, 3.47, 5.58, 2.29, 2.34, 0.24, 0.58, 0.43, 0.99, 1.87, and 3.84 Tg/a, respectively. Taking C emission as an example, 90% of SSEA’s emissions come from SEAS, especially concentrated in Laos and western Thailand. Due to the La Niña climate anomaly in 2021, emissions surged, while EQAS showed continuous annual growth at 16.7%. Forest and woodland fires were the dominant sources, accounting for over 85% of total emissions. Compared with datasets such as the Global Fire Emissions Database (GFED) and the Global Fire Assimilation System (GFAS), FY-4A showed stronger sensitivity and regional adaptability, especially in SEAS. This work provides a robust dataset for carbon source identification, air quality modeling, and regional pollution control strategies. Full article

Recent climate change has intensified extreme rainfall events, exacerbating soil erosion and agricultural nonpoint source pollution in South Korea’s steeply sloped farmlands. This study assessed soil erosion reduction measures by applying individual Best Management Practices (BMPs) in cropland and expanding upon existing management efforts through the implementation of additional BMPs aimed at further reducing soil erosion. Furthermore, priority management areas were identified based on soil erosion reduction efficiency within subbasins. For this evaluation, the Soil and Water Assessment Tool (SWAT) was employed, with a spatially distributed Hydrological Response Unit (SD-HRU) module and calibrated Modified Universal Soil Loss Equation (MUSLE) parameters tailored to Korean watershed conditions. Scenarios 1 and 2 were implemented in the study area to evaluate BMP effectiveness in controlling soil erosion and suspended sediment (SS) loads. Scenario 1 applied a set of BMPs already in place, while Scenario 2 involved the addition of supplementary BMPs to enhance soil erosion control. Scenario 1 resulted in a 34.6% reduction in annual soil erosion and a 35.0% decrease in SS concentration, whereas Scenario 2 achieved a 59.3% reduction in soil erosion and a 57.3% decrease in SS concentration. Subbasin-scale evaluations revealed considerable spatial variability in erosion control efficiency, ranging from 1.3% to 70.5%, highlighting the necessity for spatially targeted management strategies. These results underscore the importance of employing spatially adaptive BMP approaches and offer practical guidance for enhancing watershed sustainability, particularly in regions vulnerable to extreme hydrometeorological events. Full article

Reducing pesticide use is of great significance for ensuring the quality and safety of agricultural products, as well as alleviating agricultural non-point source pollution. Exploring the mechanisms by which environmental regulation drives pesticide reduction under different scenarios can help improve policy effectiveness and promote the sustainable development of agriculture. Utilizing panel data from 30 Chinese provinces spanning the period of 2010 to 2023, this study empirically analyzed the impact of environmental regulation on pesticide use through a fixed-effect model and further explored the moderating role of agricultural economic scale in this process. Moreover, a heterogeneity analysis was conducted based on regional and environmental regulation dimensions, respectively. The findings reveal that, overall, there exists an inverted U-shaped relationship between environmental regulation and pesticide use, where it initially increases and then decreases. Agricultural economic scale, serving as a moderating variable, amplifies the promotional effect of environmental regulation on pesticide reduction and accelerates the attainment of the inflection point of the inverted U-shaped curve. Regional heterogeneity analyses reveal an inverted U-shaped relationship between environmental regulation and pesticide use in the eastern and central regions, while this relationship is not significant in the western region. Notably, market-based environmental regulation exhibits a more pronounced impact compared to command-and-control environmental regulation. Full article

As an important industry in ecologically fragile areas, the synergy of agricultural pollution control and carbon reduction is vital for the balanced development of industries and regional synergy. This paper aims to explore the synergistic result of agricultural pollution control and carbon reduction in ecologically fragile areas so as to clarify the weak links and solve carbon pollution in ecologically fragile areas. Leveraging the 2006–2021 municipal data of ecologically fragile areas, this paper calculates the coupling coordination degree (CCD) of agricultural non-point source pollution and agricultural carbon emission in ecologically fragile areas; calculates the decoupling relationship between agricultural carbon emissions, pollutants, and gross agricultural output based on the Tapio decoupling index; and quantitatively depicts the synergy of agricultural pollution control and carbon reduction in ecologically fragile areas. From 2006 to 2021, agricultural carbon emissions in ecologically fragile areas depicted a fluctuating and increasing trend. Agricultural non-point source pollution depicted an “inverted U-shaped” growth trend. The emission trends of agricultural carbon emissions and agricultural pollutants depict that although agricultural pollutants and carbon emissions are homologous, there is heterogeneity in the trend and change in emissions. The synergistic results of agricultural pollution control and carbon reduction show a fluctuating upward trend in ecologically fragile areas, and the coordination degree of ecologically fragile areas increased from 0.32 to 0.89, indicating that the level of coordinated development between agricultural pollution control and carbon reduction increased significantly. Taking into account the decoupling effect, the decoupling state of agricultural carbon pollution synergistic economic growth in ecologically fragile areas has changed from negative decoupling to strong decoupling to weak decoupling, mainly in the state of strong decoupling, negative decoupling of expansion, and weak decoupling; in addition, the synergistic capacity of agricultural pollution control and carbon reduction needs to be further optimized. Based on the research results, there is some room for improvement in agricultural carbon pollution synergy in ecologically fragile areas, and regions should strengthen regional cooperation. Full article

Agricultural non-point source pollution (ANPSP) significantly affects worldwide water quality, soil integrity, and ecosystems. Primary factors are nutrient runoff, pesticide leaching, and inadequate livestock waste management. Nonetheless, a thorough assessment of ANPSP sources and efficient control techniques is still lacking. This research delineates the origins and present state of ANPSP, emphasizing its influence on agricultural practices, livestock, and rural waste management. It assesses current evaluation models, encompassing field- and watershed-scale methodologies, and investigates novel technologies such as Artificial Intelligence (AI), Machine Learning (ML), and the Internet of Things (IoT) that possess the potential to enhance pollution monitoring and predictive precision. The research examines strategies designed to alleviate ANPSP, such as sustainable agricultural practices, fertilizer reduction, and waste management technology, highlighting the necessity for integrated, real-time monitoring systems. This report presents a comprehensive analysis of current tactics, finds significant gaps, and offers recommendations for enhancing both research and policy initiatives to tackle ANPSP and foster sustainable farming practices. Full article