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Gülüt KY, Şentürk GG. Impact of nitrogen fertilizer type and application rate on growth, nitrate accumulation, and postharvest quality of spinach. PeerJ 2024; 12:e17726. [PMID: 39011375 PMCID: PMC11249000 DOI: 10.7717/peerj.17726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Accepted: 06/20/2024] [Indexed: 07/17/2024] Open
Abstract
Background A balanced supply of nitrogen is essential for spinach, supporting both optimal growth and appropriate nitrate (NO3 -) levels for improved storage quality. Thus, choosing the correct nitrogen fertilizer type and application rate is key for successful spinach cultivation. This study investigated the effects of different nitrogen (N) fertilizer type and application rates on the growth, nitrate content, and storage quality of spinach plants. Methods Four fertilizer types were applied at five N doses (25, 50, 200, and 400 mg N kg-1) to plants grown in plastic pots at a greenhouse. The fertilizer types used in the experiment were ammonium sulphate (AS), slow-release ammonium sulphate (SRAS), calcium nitrate (CN), and yeast residue (YR). Spinach parameters like Soil Plant Analysis Development (SPAD) values (chlorophyll content), plant height, and fresh weight were measured. Nitrate content in leaves was analyzed after storage periods simulating post-harvest handling (0, 5, and 10 days). Results The application of nitrogen fertilizer significantly influenced spinach growth parameters and nitrate content. The YRx400 treatment yielded the largest leaves (10.3 ± 0.5 cm long, 5.3 ± 0.2 cm wide). SPAD values increased with higher N doses for AS, SRAS, and CN fertilizers, with AS×400 (58.1 ± 0.8) and SRAS×400 (62.0 ± 5.8) reaching the highest values. YR treatments showed a moderate SPAD increase. Fresh weight response depended on fertilizer type, N dose, and storage period. While fresh weight increased in all fertilizers till 200 mg kg-1 dose, a decrease was observed at the highest dose for AS and CN. SRAS exhibited a more gradual increase in fresh weight with increasing nitrogen dose, without the negative impact seen at the highest dose in AS and CN. Nitrate content in spinach leaves varied by fertilizer type, dose, and storage day. CNx400 resulted in the highest NO3 - content (4,395 mg kg-1) at harvest (Day 0), exceeding the European Union's safety limit. This level decreased over 10 days of storage but remained above the limit for CN on Days 0 and 5. SRAS and YR fertilizers generally had lower NO3 - concentrations throughout the experiment. Storage at +4 °C significantly affected NO3 - content. While levels remained relatively stable during the first 5 days, a substantial decrease was observed by Day 10 for all fertilizers and doses, providing insights into the spinach's nitrate content over a 10-day storage period. Conclusion For rapid early growth and potentially higher yields, AS may be suitable at moderate doses (200 mg kg-1). SRAS offers a more balanced approach, promoting sustained growth while potentially reducing NO3 - accumulation compared to AS. Yeast residue, with its slow nitrogen release and consistently low NO3 - levels, could be a viable option for organic spinach production.
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Affiliation(s)
- Kemal Yalçın Gülüt
- Department of Soil Science and Plant Nutrition/Faculty of Agriculture, Çukurova University, Sarıçam, Adana, Turkey
| | - Gamze Güleç Şentürk
- Department of Soil Science and Plant Nutrition/Faculty of Agriculture, Çukurova University, Sarıçam, Adana, Turkey
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Wang D, Wu J, Li P, Li L, Yang J, Zhang P, He S, Kou X, Wang Y. Seasonal nitrate variations, risks, and sources in groundwater under different land use types in a thousand-year-cultivated region, northwestern China. ENVIRONMENTAL RESEARCH 2024; 251:118699. [PMID: 38493861 DOI: 10.1016/j.envres.2024.118699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 03/09/2024] [Accepted: 03/11/2024] [Indexed: 03/19/2024]
Abstract
The global public health concern of nitrate (NO3-) contamination in groundwater is particularly pronounced in irrigated agricultural regions. This paper aims to analyze the spatial distribution of groundwater NO3-, assess potential health risks for local residents, and quantitatively identify nitrate sources during different seasons and land use types in the Jinghuiqu Irrigation District, a region in northwestern China with a longstanding agricultural history. The investigation utilizes hydrochemical parameters, dual isotopic data, and the Bayesian stable isotope mixing model (MixSIAR). The findings underscore significant seasonal variations in the average concentrations of NO3-, with values of 87.72 mg/L and 101.87 mg/L during the wet and dry seasons, respectively. Furthermore, distinct fluctuations in nitrate concentration were observed across different land use types, whereby vegetable lands manifested the maximum concentration. Prolonged exposure to elevated nitrate concentrations may pose potential health risks to residents, especially in the dry season when the non-carcinogenic groundwater nitrate risk surges past its wet season counterpart. The MixSIAR analysis revealed that chemical fertilizers accounted for the majority of nitrate pollution in vegetable lands, both during the dry season (49.6%) and wet season (41.2%). In contrast, manure and sewage contributed significantly to NO3-concentrations in residential land during the wet (74.9%) and dry seasons (67.6%). For croplands, soil nitrogen emerged as a dominant source during the wet season (42.2%), while chemical fertilizers prevailed in the dry season (38.7%). In addition to source variations, the nitrate concentration of groundwater is further affected by hydrogeological conditions, with more permeable aquifers tending to display higher nitrate concentrations. Thus, targeted measures were proposed to modify or impede the nitrogen migration pathway, taking into consideration hydrogeological conditions and incorporating domestic sewage, organic fertilizer, and agricultural management practices.
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Affiliation(s)
- Dan Wang
- School of Water and Environment, Chang'an University, No. 126 Yanta Road, Xi'an, 710054, Shaanxi, China; Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region of the Ministry of Education, Chang'an University, No. 126 Yanta Road, Xi'an, 710054, Shaanxi, China; Key Laboratory of Eco-hydrology and Water Security in Arid and Semi-arid Regions of the Ministry of Water Resources, Chang'an University, No. 126 Yanta Road, Xi'an, 710054, Shaanxi, China
| | - Jianhua Wu
- School of Water and Environment, Chang'an University, No. 126 Yanta Road, Xi'an, 710054, Shaanxi, China; Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region of the Ministry of Education, Chang'an University, No. 126 Yanta Road, Xi'an, 710054, Shaanxi, China; Key Laboratory of Eco-hydrology and Water Security in Arid and Semi-arid Regions of the Ministry of Water Resources, Chang'an University, No. 126 Yanta Road, Xi'an, 710054, Shaanxi, China.
| | - Peiyue Li
- School of Water and Environment, Chang'an University, No. 126 Yanta Road, Xi'an, 710054, Shaanxi, China; Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region of the Ministry of Education, Chang'an University, No. 126 Yanta Road, Xi'an, 710054, Shaanxi, China; Key Laboratory of Eco-hydrology and Water Security in Arid and Semi-arid Regions of the Ministry of Water Resources, Chang'an University, No. 126 Yanta Road, Xi'an, 710054, Shaanxi, China.
| | - Lingxi Li
- School of Water and Environment, Chang'an University, No. 126 Yanta Road, Xi'an, 710054, Shaanxi, China; Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region of the Ministry of Education, Chang'an University, No. 126 Yanta Road, Xi'an, 710054, Shaanxi, China; Key Laboratory of Eco-hydrology and Water Security in Arid and Semi-arid Regions of the Ministry of Water Resources, Chang'an University, No. 126 Yanta Road, Xi'an, 710054, Shaanxi, China
| | - Junyan Yang
- School of Water and Environment, Chang'an University, No. 126 Yanta Road, Xi'an, 710054, Shaanxi, China; Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region of the Ministry of Education, Chang'an University, No. 126 Yanta Road, Xi'an, 710054, Shaanxi, China; Key Laboratory of Eco-hydrology and Water Security in Arid and Semi-arid Regions of the Ministry of Water Resources, Chang'an University, No. 126 Yanta Road, Xi'an, 710054, Shaanxi, China
| | - Pengbin Zhang
- School of Water and Environment, Chang'an University, No. 126 Yanta Road, Xi'an, 710054, Shaanxi, China; Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region of the Ministry of Education, Chang'an University, No. 126 Yanta Road, Xi'an, 710054, Shaanxi, China; Key Laboratory of Eco-hydrology and Water Security in Arid and Semi-arid Regions of the Ministry of Water Resources, Chang'an University, No. 126 Yanta Road, Xi'an, 710054, Shaanxi, China
| | - Song He
- PowerChina Northwest Engineering Corporation Limited, No. 18 Zhangbadong Road, Xi'an, 710065, Shaanxi, China
| | - Xiaomei Kou
- PowerChina Northwest Engineering Corporation Limited, No. 18 Zhangbadong Road, Xi'an, 710065, Shaanxi, China
| | - Yong Wang
- PowerChina Sinohydro Bureau 3 Co.,LTD., No. 4069 Expo Avenue, Chanba Ecological District, Xi'an, 710024, Shaanxi, China
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Hao Y, Li J, Li Z, Peng Y, Hussain S, Fu T, Li H, Chang J, Chen L, Zhang B. Greenhouse gas emissions and their driving factors among different flowering Chinese cabbage (Brassica campestris L.) varieties. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:38217-38231. [PMID: 38795300 DOI: 10.1007/s11356-024-33769-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2024] [Accepted: 05/19/2024] [Indexed: 05/27/2024]
Abstract
Crop cultivars have an influence on greenhouse gas (GHG) emissions, and there is variation between varieties. However, there are few reports available on the differences in GHG emissions and their driving factors among vegetable varieties. In this study, we conducted a field experiment to examine the variances in GHG emissions and their contributing factors among eight flowering Chinese cabbage varieties (considering growth period, leaf shape, and colour). The results showed significant differences in GHG emissions within varieties; early-maturing varieties exhibited GHG by 25.6% and 15.3%, respectively, when compared to mid- and late-maturing varieties. Among the different leaf types and color classifications, light-colored and sharp-leafed varieties had the lower global warming potential (GWP) overall. Cumulative CO2 emissions were influenced by leaf SPAD values and biomass, while cumulative N2O emissions were driven mainly by stem thickness, carbon accumulation, leaf SPAD values, and biomass. In summary, the selection of light-colored varieties with pointed leaves and shorter growth periods in actual production contributed positively to the reduction of carbon emissions from flowering Chinese cabbage production. Through efficient variety screening, this study provides a win-win strategy for achieving efficient vegetable production while also addressing the global climate challenge.
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Affiliation(s)
- Yongzhou Hao
- Key Laboratory for New Technology Research of Vegetables, Vegetable Research Institute, Guangdong Academy of Agricultural Science, No.66, Jinying Road, Tianhe District, Guangzhou, 510640, China
- Faculty of Food Science and Engineering, Foshan University, Foshan, 258000, China
| | - Jing Li
- Key Laboratory for New Technology Research of Vegetables, Vegetable Research Institute, Guangdong Academy of Agricultural Science, No.66, Jinying Road, Tianhe District, Guangzhou, 510640, China
| | - Zhen Li
- Key Laboratory for New Technology Research of Vegetables, Vegetable Research Institute, Guangdong Academy of Agricultural Science, No.66, Jinying Road, Tianhe District, Guangzhou, 510640, China
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops; Fujian Provincial Key Laboratory of Agroecological Processing and Safety Monitoring, College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Yutao Peng
- School of Agriculture, Sun Yat-sen University, Shenzhen, 518107, China
| | - Shahid Hussain
- Key Laboratory for New Technology Research of Vegetables, Vegetable Research Institute, Guangdong Academy of Agricultural Science, No.66, Jinying Road, Tianhe District, Guangzhou, 510640, China
| | - Tianhong Fu
- Key Laboratory for New Technology Research of Vegetables, Vegetable Research Institute, Guangdong Academy of Agricultural Science, No.66, Jinying Road, Tianhe District, Guangzhou, 510640, China
| | - Hongzhao Li
- Key Laboratory for New Technology Research of Vegetables, Vegetable Research Institute, Guangdong Academy of Agricultural Science, No.66, Jinying Road, Tianhe District, Guangzhou, 510640, China
- Faculty of Food Science and Engineering, Foshan University, Foshan, 258000, China
| | - Jingjing Chang
- Key Laboratory for New Technology Research of Vegetables, Vegetable Research Institute, Guangdong Academy of Agricultural Science, No.66, Jinying Road, Tianhe District, Guangzhou, 510640, China
| | - Lei Chen
- Key Laboratory for New Technology Research of Vegetables, Vegetable Research Institute, Guangdong Academy of Agricultural Science, No.66, Jinying Road, Tianhe District, Guangzhou, 510640, China
| | - Baige Zhang
- Key Laboratory for New Technology Research of Vegetables, Vegetable Research Institute, Guangdong Academy of Agricultural Science, No.66, Jinying Road, Tianhe District, Guangzhou, 510640, China.
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Fan Y, Feng Q, Huang Y, Yang N, Fan H, Li B, Wang X, Yang L, Yen H, Wu F, Chen L. Determining optimal range of reduction rates for nitrogen fertilization based on responses of vegetable yield and nitrogen losses to reduced nitrogen fertilizer application. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 924:171523. [PMID: 38453078 DOI: 10.1016/j.scitotenv.2024.171523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 02/21/2024] [Accepted: 03/04/2024] [Indexed: 03/09/2024]
Abstract
Vegetable production is commonly accompanied by high nitrogen fertilizer rates but low nitrogen use efficiency in China. Reduced fertilization has been frequently recommended in existing studies as an efficient measurement to avoid large amount of nutrient loss and subsequent nonpoint source pollution. However, the reported responses of vegetable yield and nitrogen losses to reduced fertilization rates varied in a large range, which has resulted into large uncertainties in the potential benefits of those recommended reduction rates. Thus, we constructed the relationship between responses of nitrogen losses and vegetable yield to reduced nitrogen fertilization rates to determine the optimal range of reduction rates for nitrogen fertilization in a proportional form based on data reported in literatures across China's mainland, and evaluated the roles of greenhouse, managing options, and vegetable species on the responses. The relationships were constructed separately for 4 subregions: Northern arid and semiarid, loess plateau regions (NSL), Temperate monsoon zone (TMZ), Southeast monsoon zone (SMZ), Southwest zone (SWZ). The optimal nitrogen fertilizer reduction range for the TMZ, SMZ and SWZ were 51 % to 67 %, 40 % to 66 % and 54 % to 80 %, respectively and no reduction for NSL. Vegetable yields were not be sacrificed when fertilizations were reduced within the optimal ranges. Greenhouse and managing options showed no significant effect on the responses of both vegetable yield and nitrogen losses by the optimal reduction range but vegetable species played a relatively important role on the responses of vegetable yield. This indicated that the optimal reduction rates can be effective on reducing nitrogen loss in both open-field and greenhouse conditions across China's mainland without extra managing options. Therefore, the optimal reduction rates can still serve as a good starting point for making regional plans of nitrogen reduction that help balancing the chasing of high vegetable yield and low nitrogen loss.
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Affiliation(s)
- Yinlin Fan
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Science, Beijing 100085, China; Institute of International Rivers and Eco-Security, Yunnan University, Kunming 650091, China
| | - Qingyu Feng
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Science, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
| | - Yong Huang
- Institute of International Rivers and Eco-Security, Yunnan University, Kunming 650091, China
| | - Nengliang Yang
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Science, Beijing 100085, China; Institute of International Rivers and Eco-Security, Yunnan University, Kunming 650091, China
| | - Huihui Fan
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Science, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Boyong Li
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Science, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Xinyan Wang
- School of Landscape Architecture, Beijing Forestry University, Beijing 100091, China
| | - Lei Yang
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Science, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Haw Yen
- School of Forestry and Wildlife Sciences, Auburn University, Auburn, AL 36849, USA; Environmental Exposure Modeling, Regulatory Science North America, Bayer US Crop Science Division, Chesterfield, MO 63017, USA
| | - Feng Wu
- Center for Chinese Agricultural Policy, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Liding Chen
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Science, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, PR China
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Wang D, Li P, Mu D, Liu W, Chen Y, Fida M. Unveiling the biogeochemical mechanism of nitrate in the vadose zone-groundwater system: Insights from integrated microbiology, isotope techniques, and hydrogeochemistry. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 906:167481. [PMID: 37788773 DOI: 10.1016/j.scitotenv.2023.167481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 09/09/2023] [Accepted: 09/28/2023] [Indexed: 10/05/2023]
Abstract
Clarifying the biogeochemical mechanism of nitrate (NO3-) in the vadose zone-groundwater system, particularly in agricultural contexts, is crucial for mitigating groundwater NO3- pollution. However, comprehensive studies on the impacts of changes in chemical indicators and microbial communities on NO3- are still lacking. This paper aims to address this gap by employing hydrogeochemistry, stable isotopes, and microbial techniques to assess the NO3- biogeochemical processes in the vadose zone-groundwater system. The findings suggested that NO3- in upper soil layers was primarily influenced by plant root absorption, assimilation, and nitrification processes. The oxygen contents gradually decreased with the nitrification process, resulting in the occurrence of the denitrification. However, denitrification predominantly occurred in the 60-80 cm soil layer in the study area. The limited thickness of the denitrification layer results in less NO3- consumption, leading to increased NO3- leaching into groundwater. Hydrochemical and isotopic characteristics further indicated that groundwater NO3- concentrations were mainly controlled by nitrification, followed by denitrification and mixing processes. The 16S rRNA sequencing analysis revealed great influences of soil sampling depths and groundwater NO3- concentrations on the microbial community structure. Additionally, the PICRUSt2-based prediction results demonstrated a stronger potential for dissimilatory reduction of NO3- to ammonium (DNRA) in both soil and groundwater compared to the other processes, potentially due to the widespread presence of the nrfH functional genes. However, the chemical indicators and isotopes used in this study did not support the occurrence of DNRA process in the vadose zone-groundwater system. This finding highlights the importance of an integrated approach combining microbiological, isotopic, and hydrogeochemical data to comprehensive understanding biogeochemical processes. The study developed a conceptual model elucidating the NO3- biogeochemical processes in the vadose zone-groundwater system within an agricultural area, contributing to enhanced comprehension and advancement of sustainable management practices for groundwater nitrogen.
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Affiliation(s)
- Dan Wang
- School of Water and Environment, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China; Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region of the Ministry of Education, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China; Key Laboratory of Eco-hydrology and Water Security in Arid and Semi-arid Regions of the Ministry of Water Resources, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China
| | - Peiyue Li
- School of Water and Environment, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China; Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region of the Ministry of Education, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China; Key Laboratory of Eco-hydrology and Water Security in Arid and Semi-arid Regions of the Ministry of Water Resources, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China.
| | - Dawei Mu
- School of Water and Environment, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China; Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region of the Ministry of Education, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China; Key Laboratory of Eco-hydrology and Water Security in Arid and Semi-arid Regions of the Ministry of Water Resources, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China
| | - Weichao Liu
- School of Water and Environment, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China; Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region of the Ministry of Education, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China; Key Laboratory of Eco-hydrology and Water Security in Arid and Semi-arid Regions of the Ministry of Water Resources, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China
| | - Yinfu Chen
- School of Water and Environment, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China; Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region of the Ministry of Education, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China; Key Laboratory of Eco-hydrology and Water Security in Arid and Semi-arid Regions of the Ministry of Water Resources, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China
| | - Misbah Fida
- School of Water and Environment, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China; Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region of the Ministry of Education, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China; Key Laboratory of Eco-hydrology and Water Security in Arid and Semi-arid Regions of the Ministry of Water Resources, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China
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Wang D, Li P, Yang N, Yang C, Zhou Y, Li J. Distribution, sources and main controlling factors of nitrate in a typical intensive agricultural region, northwestern China: Vertical profile perspectives. ENVIRONMENTAL RESEARCH 2023; 237:116911. [PMID: 37597825 DOI: 10.1016/j.envres.2023.116911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 07/29/2023] [Accepted: 08/16/2023] [Indexed: 08/21/2023]
Abstract
Nitrate (NO3-) pollution of groundwater is a global concern in agricultural areas. To gain a comprehensive understanding of the sources and destiny of nitrate in soil and groundwater within intensive agricultural areas, this study employed a combination of chemical indicators, dual isotopes of nitrate (δ15N-NO3- and δ18O-NO3-), random forest model, and Bayesian stable isotope mixing model (MixSIAR). These approaches were utilized to examine the spatial distribution of NO3- in soil profiles and groundwater, identify key variables influencing groundwater nitrate concentration, and quantify the sources contribution at various depths of the vadose zone and groundwater with different nitrate concentrations. The results showed that the nitrate accumulation in the cropland and kiwifruit orchard at depths of 0-400 cm increased, leading to subsequent leaching of nitrate into deeper vadose zones and ultimately groundwater. The mean concentration of nitrate in groundwater was 91.89 mg/L, and 52.94% of the samples exceeded the recommended grade III value (88.57 mg/L) according to national standards. The results of the random forest model suggested that the main variables affecting the nitrate concentration in groundwater were well depth (16.6%), dissolved oxygen (11.6%), and soil nitrate (10.4%). The MixSIAR results revealed that nitrate sources vary at different soil depths, which was caused by the biogeochemical process of nitrate. In addition, the highest contribution of nitrate in groundwater, both with high and low concentrations, was found to be soil nitrogen (SN), accounting for 56.0% and 63.0%, respectively, followed by chemical fertilizer (CF) and manure and sewage (M&S). Through the identification of NO3- pollution sources, this study can take targeted measures to ensure the safety of groundwater in intensive agricultural areas.
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Affiliation(s)
- Dan Wang
- School of Water and Environment, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China; Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region of the Ministry of Education, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China; Key Laboratory of Eco-hydrology and Water Security in Arid and Semi-arid Regions of the Ministry of Water Resources, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China
| | - Peiyue Li
- School of Water and Environment, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China; Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region of the Ministry of Education, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China; Key Laboratory of Eco-hydrology and Water Security in Arid and Semi-arid Regions of the Ministry of Water Resources, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China.
| | - Ningning Yang
- School of Water and Environment, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China; Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region of the Ministry of Education, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China; Key Laboratory of Eco-hydrology and Water Security in Arid and Semi-arid Regions of the Ministry of Water Resources, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China
| | - Chunliu Yang
- School of Water and Environment, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China; Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region of the Ministry of Education, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China; Key Laboratory of Eco-hydrology and Water Security in Arid and Semi-arid Regions of the Ministry of Water Resources, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China
| | - Yuhan Zhou
- School of Water and Environment, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China; Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region of the Ministry of Education, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China; Key Laboratory of Eco-hydrology and Water Security in Arid and Semi-arid Regions of the Ministry of Water Resources, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China
| | - Jiahui Li
- School of Water and Environment, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China; Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region of the Ministry of Education, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China; Key Laboratory of Eco-hydrology and Water Security in Arid and Semi-arid Regions of the Ministry of Water Resources, Chang'an University, No. 126 Yanta Road, Xi'an 710054, Shaanxi, China
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Luetic S, Knezovic Z, Jurcic K, Majic Z, Tripkovic K, Sutlovic D. Leafy Vegetable Nitrite and Nitrate Content: Potential Health Effects. Foods 2023; 12:foods12081655. [PMID: 37107450 PMCID: PMC10137473 DOI: 10.3390/foods12081655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 04/12/2023] [Accepted: 04/13/2023] [Indexed: 04/29/2023] Open
Abstract
The aim of this research was to determine the concentrations of nitrates and nitrites in different types of vegetables that are commonly represented in the diet of the inhabitants of Split and Dalmatian County. Therefore, using the method of random selection, there were 96 samples of different vegetables. The determination of the nitrate and nitrite concentrations was carried out by high-pressure liquid chromatography (HPLC) with a diode array detector (DAD). The nitrate concentrations in the range 2.1-4526.3 mg kg-1 were found in 92.7% of the analyzed samples. The highest nitrate values were found in rucola (Eruca sativa L.) followed by Swiss chard (Beta vulgaris L.). In 36.5% of the leafy vegetables intended for consumption without prior heat treatment, nitrite was found in the range of 3.3-537.9 mg kg-1. The high levels of nitrite in the vegetables intended for fresh consumption and the high nitrate values in Swiss chard indicate the need to establish maximum nitrite limits in vegetables, as well as the broadening of legal nitrate limits to wide varieties of vegetables.
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Affiliation(s)
- Sanja Luetic
- Teaching Institute for Public Health, Split-Dalmatia County, 21000 Split, Croatia
| | - Zlatka Knezovic
- Teaching Institute for Public Health, Split-Dalmatia County, 21000 Split, Croatia
- Department of Health Studies, University of Split, 21000 Split, Croatia
| | - Katarina Jurcic
- Teaching Institute for Public Health, Split-Dalmatia County, 21000 Split, Croatia
| | - Zrinka Majic
- Teaching Institute for Public Health, Split-Dalmatia County, 21000 Split, Croatia
| | - Ksenija Tripkovic
- Teaching Institute for Public Health, Split-Dalmatia County, 21000 Split, Croatia
| | - Davorka Sutlovic
- Department of Health Studies, University of Split, 21000 Split, Croatia
- Department of Toxicology and Pharmacogenetics, School of Medicine, University of Split, 21000 Split, Croatia
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8
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Gong Y, Li X, Xie P, Fu H, Nie L, Li J, Li Y. The migration and accumulation of typical pollutants in the growing media layer of bioretention facilities. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:44591-44606. [PMID: 36694065 PMCID: PMC9873394 DOI: 10.1007/s11356-023-25305-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 01/10/2023] [Indexed: 06/17/2023]
Abstract
A series of complex physical and chemical processes, such as interception, migration, accumulation, and transformation, can occur when pollutants in stormwater runoff enter the growing media layer of bioretention facilities, affecting the purification of stormwater runoff by bioretention facilities. The migration and accumulation of pollutants in the growing media layer need long-term monitoring in traditional experimental studies. In this study, we established the Hydrus-1D model of water and solution transport for the bioretention facilities. By analyzing the variation of cumulative fluxes of NO3--N and Pb with time and depth, we investigated pollutant migration and accumulation trends in the growing media layer of bioretention facilities. It can provide support for reducing runoff pollutants in bioretention facilities. The Hydrus-1D model was calibrated and verified with experimental data, and the input data (runoff pollutant concentration) for the pollutant concentration boundary was obtained from the SWMM model. The results demonstrated that the cumulative fluxes of NO3--N and Pb increased with the passage of simulation time and depth of the growing media layer overall. From the top to the bottom of the growing media layer, the change rates of the peak cumulative fluxes of NO3--N and Pb were strongly linked with their levels in the runoff. An increase in rainfall decreased the content of NO3--N and Pb in the growing media layer, and this phenomenon was more obvious in the lower part of the layer.
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Affiliation(s)
- Yongwei Gong
- Key Laboratory of Urban Stormwater System and Water Environment, Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China
| | - Xia Li
- Key Laboratory of Urban Stormwater System and Water Environment, Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China
| | - Peng Xie
- Key Laboratory of Urban Stormwater System and Water Environment, Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China
| | - Hongyan Fu
- Key Laboratory of Urban Stormwater System and Water Environment, Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China
- Qingdao Planning Engineering Design Research Institute Co., Ltd., Qingdao, 266000, China
| | - Linmei Nie
- Centre for Sustainable Development and Innovation of Water Technology, 0957, Oslo, Norway
| | - Junqi Li
- Key Laboratory of Urban Stormwater System and Water Environment, Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China.
| | - Yanhong Li
- Beijing Guohuan Tsinghua Environmental Engineering Design & Research Institute Co., Ltd., Beijing, 100084, China
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9
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Li C, Wei Z, Yang P, Shan J, Yan X. Conversion from rice fields to vegetable fields alters product stoichiometry of denitrification and increases N 2O emission. ENVIRONMENTAL RESEARCH 2022; 215:114279. [PMID: 36126691 DOI: 10.1016/j.envres.2022.114279] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 08/30/2022] [Accepted: 09/02/2022] [Indexed: 06/15/2023]
Abstract
Information about effects of conversion from rice fields to vegetable fields on denitrification process is still limited. In this study, denitrification rate and product ratio (i.e., N2O/(N2O + N2) ratio) were investigated by soil-core incubation based N2/Ar technique in one rice paddy field (RP) and two vegetable fields (VF4 and VF7, 4 and 7 years vegetable cultivating after conversion from rice fields, respectively). Genes related to denitrification and bacterial community composition were quantified to investigate the microbial mechanisms behind the effects of land-use conversion. The results showed that conversion of rice fields to vegetable fields did not significantly change denitrification rate although the abundance of denitrification related genes was significantly reduced by 79.22%-99.84% in the vegetable soils. Whereas, compared with the RP soil, N2O emission rate was significantly (P < 0.05) increased by 53.5 and 1.6 times in the VF4 and VF7 soils, respectively. Correspondingly, the N2O/(N2O + N2) ratio increased from 0.18% (RP soil) to 5.65% and 0.65% in the VF4 and VF7 soils, respectively. These changes were mainly attributed to the lower pH, higher nitrate content, and the altered bacterial community composition in the vegetable soils. Overall, our results showed that conversion of rice fields to vegetable fields increased the N2O emission rate and altered the product ratio of denitrification. This may increase the contribution of land-use conversion to global warming and stratospheric ozone depletion.
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Affiliation(s)
- Chenglin Li
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Changshu National Agro-Ecosystem Observation and Research Station, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Zhijun Wei
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Changshu National Agro-Ecosystem Observation and Research Station, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Pinpin Yang
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Jun Shan
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China; Changshu National Agro-Ecosystem Observation and Research Station, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China.
| | - Xiaoyuan Yan
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China; Changshu National Agro-Ecosystem Observation and Research Station, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China
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10
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Weitzman JN, Brooks JR, Compton JE, Faulkner BR, Mayer PM, Peachey RE, Rugh WD, Coulombe RA, Hatteberg B, Hutchins SR. Deep soil nitrogen storage slows nitrate leaching through the vadose zone. AGRICULTURE, ECOSYSTEMS & ENVIRONMENT 2022; 332:1-13. [PMID: 35400773 DOI: 10.23719/1524264] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Nitrogen (N) fertilizer applications are important for agricultural yield, yet not all the applied N is taken up by crops, leading to surplus N storage in soil or leaching to groundwater and surface water. Leaching loss of fertilizer N represents a cost for farmers and has consequences for human health and the environment, especially in the southern Willamette Valley, Oregon, USA, where groundwater nitrate contamination is prevalent. While improved nutrient management and conservation practices have been implemented to minimize leaching, nitrate levels in groundwater continue to increase in many long-term monitoring wells. To elucidate controls on leaching rates and N dynamics in agricultural soils across soil depths, and in response to seasonal and annual variation in management (e.g., fertilizer input amount and summer irrigation), we intensively monitored the transport of water and nitrate every two weeks for four years through the vadose zone at three depths (0.8, 1.5, and 3.0 m) in a sweet corn (maize) field. Though nitrate leaching was highly variable among lysimeters at the same depth and across years, a strong pattern emerged: annual nitrate leaching significantly decreased with depth across the study, averaging ~104 kg N ha-1 yr-1 near the surface (0.8 m) versus ~56 kg N ha-1 yr-1 in the deep soil (3.0 m), a 54% reduction in leaching between the soil layers. Even though crops were irrigated in summer, most leaching (~72% below 3.0 m) occurred during the wet fall and winter. Based on steady state assumptions, a net equivalent of ~29% of surface N inputs leached below 3.0 m into the deeper soil and groundwater, while ~44% was removed in crop harvest, indicating considerable N retention in the soil (~27% of inputs or approximately 58 kg N ha-1 yr-1). The accumulation and long-term dynamics of deep soil N is a legacy of agricultural management that should be further studied to better manage and reduce nitrate loss to groundwater.
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Affiliation(s)
- Julie N Weitzman
- ORISE Fellow at Pacific Ecological Systems Division, Center for Public Health and Environmental Assessment, Office of Research and Development, US Environmental Protection Agency, 200 SW 35 Street, Corvallis, OR, 97333, USA
| | - J Renée Brooks
- Pacific Ecological Systems Division, Center for Public Health and Environmental Assessment, Office of Research and Development, US Environmental Protection Agency, 200 SW 35 Street, Corvallis, OR, 97333, USA
| | - Jana E Compton
- Pacific Ecological Systems Division, Center for Public Health and Environmental Assessment, Office of Research and Development, US Environmental Protection Agency, 200 SW 35 Street, Corvallis, OR, 97333, USA
| | - Barton R Faulkner
- Groundwater Characterization and Remediation Division, Center for Environmental Solutions and Emergency Response, Office of Research and Development, US Environmental Protection Agency, 919 Kerr Research Drive, Ada, OK, 74820, USA
| | - Paul M Mayer
- Pacific Ecological Systems Division, Center for Public Health and Environmental Assessment, Office of Research and Development, US Environmental Protection Agency, 200 SW 35 Street, Corvallis, OR, 97333, USA
| | - Ronald E Peachey
- Department of Horticulture, College of Agricultural Sciences, Oregon State University, 4045 Agriculture and Life Sciences Building, Corvallis, OR, 97331, USA
| | - William D Rugh
- Pacific Ecological Systems Division, Center for Public Health and Environmental Assessment, Office of Research and Development, US Environmental Protection Agency, 200 SW 35 Street, Corvallis, OR, 97333, USA
| | | | | | - Stephen R Hutchins
- Groundwater Characterization and Remediation Division, Center for Environmental Solutions and Emergency Response, Office of Research and Development, US Environmental Protection Agency, 919 Kerr Research Drive, Ada, OK, 74820, USA
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11
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Weitzman JN, Brooks JR, Compton JE, Faulkner BR, Mayer PM, Peachey RE, Rugh WD, Coulombe RA, Hatteberg B, Hutchins SR. Deep soil nitrogen storage slows nitrate leaching through the vadose zone. AGRICULTURE, ECOSYSTEMS & ENVIRONMENT 2022; 332:1-13. [PMID: 35400773 PMCID: PMC8988158 DOI: 10.1016/j.agee.2022.107949] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Nitrogen (N) fertilizer applications are important for agricultural yield, yet not all the applied N is taken up by crops, leading to surplus N storage in soil or leaching to groundwater and surface water. Leaching loss of fertilizer N represents a cost for farmers and has consequences for human health and the environment, especially in the southern Willamette Valley, Oregon, USA, where groundwater nitrate contamination is prevalent. While improved nutrient management and conservation practices have been implemented to minimize leaching, nitrate levels in groundwater continue to increase in many long-term monitoring wells. To elucidate controls on leaching rates and N dynamics in agricultural soils across soil depths, and in response to seasonal and annual variation in management (e.g., fertilizer input amount and summer irrigation), we intensively monitored the transport of water and nitrate every two weeks for four years through the vadose zone at three depths (0.8, 1.5, and 3.0 m) in a sweet corn (maize) field. Though nitrate leaching was highly variable among lysimeters at the same depth and across years, a strong pattern emerged: annual nitrate leaching significantly decreased with depth across the study, averaging ~104 kg N ha-1 yr-1 near the surface (0.8 m) versus ~56 kg N ha-1 yr-1 in the deep soil (3.0 m), a 54% reduction in leaching between the soil layers. Even though crops were irrigated in summer, most leaching (~72% below 3.0 m) occurred during the wet fall and winter. Based on steady state assumptions, a net equivalent of ~29% of surface N inputs leached below 3.0 m into the deeper soil and groundwater, while ~44% was removed in crop harvest, indicating considerable N retention in the soil (~27% of inputs or approximately 58 kg N ha-1 yr-1). The accumulation and long-term dynamics of deep soil N is a legacy of agricultural management that should be further studied to better manage and reduce nitrate loss to groundwater.
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Affiliation(s)
- Julie N. Weitzman
- ORISE Fellow at Pacific Ecological Systems Division, Center for Public Health and Environmental Assessment, Office of Research and Development, US Environmental Protection Agency, 200 SW 35 Street, Corvallis, OR, 97333, USA
| | - J. Renée Brooks
- Pacific Ecological Systems Division, Center for Public Health and Environmental Assessment, Office of Research and Development, US Environmental Protection Agency, 200 SW 35 Street, Corvallis, OR, 97333, USA
| | - Jana E. Compton
- Pacific Ecological Systems Division, Center for Public Health and Environmental Assessment, Office of Research and Development, US Environmental Protection Agency, 200 SW 35 Street, Corvallis, OR, 97333, USA
| | - Barton R. Faulkner
- Groundwater Characterization and Remediation Division, Center for Environmental Solutions and Emergency Response, Office of Research and Development, US Environmental Protection Agency, 919 Kerr Research Drive, Ada, OK, 74820, USA
| | - Paul M. Mayer
- Pacific Ecological Systems Division, Center for Public Health and Environmental Assessment, Office of Research and Development, US Environmental Protection Agency, 200 SW 35 Street, Corvallis, OR, 97333, USA
| | - Ronald E. Peachey
- Department of Horticulture, College of Agricultural Sciences, Oregon State University, 4045 Agriculture and Life Sciences Building, Corvallis, OR, 97331, USA
| | - William D. Rugh
- Pacific Ecological Systems Division, Center for Public Health and Environmental Assessment, Office of Research and Development, US Environmental Protection Agency, 200 SW 35 Street, Corvallis, OR, 97333, USA
| | | | | | - Stephen R. Hutchins
- Groundwater Characterization and Remediation Division, Center for Environmental Solutions and Emergency Response, Office of Research and Development, US Environmental Protection Agency, 919 Kerr Research Drive, Ada, OK, 74820, USA
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12
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Elrys AS, Chen Z, Wang J, Uwiragiye Y, Helmy AM, Desoky ESM, Cheng Y, Zhang JB, Cai ZC, Müller C. Global patterns of soil gross immobilization of ammonium and nitrate in terrestrial ecosystems. GLOBAL CHANGE BIOLOGY 2022; 28:4472-4488. [PMID: 35445472 DOI: 10.1111/gcb.16202] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 03/31/2022] [Accepted: 04/13/2022] [Indexed: 06/14/2023]
Abstract
Microbial nitrogen (N) immobilization, which typically results in soil N retention but based on the balance of gross N immobilization over gross N production, affects the fate of the anthropogenic reactive N. However, global patterns and drivers of soil gross immobilization of ammonium (INH4 ) and nitrate (INO3 ) are still only tentatively known. Here, we provide a comprehensive analysis considering gross N production rates, soil properties, and climate and their interactions for a deeper understanding of the patterns and drivers of INH4 and INO3 . By compiling and analyzing 1966 observations from 274 15 N-labelled studies, we found a global average of INH4 and INO3 of 7.41 ± 0.72 and 2.03 ± 0.30 mg N kg-1 day-1 with a ratio of INO3 to INH4 (INO3 :INH4 ) of 0.79 ± 0.11. Soil INH4 and INO3 increased with increasing soil gross N mineralization (GNM) and nitrification (GN), microbial biomass, organic carbon, and total N and decreasing soil bulk density. Our analysis revealed that GNM and GN were the main stimulators for INH4 and INO3 , respectively. The structural equation modeling showed that higher soil microbial biomass, total N, pH, and precipitation stimulate INH4 and INO3 through enhancing GNM and GN. However, higher temperature and soil bulk density suppress INH4 and INO3 by reducing microbial biomass and total N. Soil INH4 varied with terrestrial ecosystems, being greater in grasslands and forests, which have higher rates of GNM, than in croplands. The highest INO3 :INH4 was observed in croplands, which had higher rates of GN. The global average of GN to INH4 was 2.86 ± 0.31, manifesting a high potential risk of N loss. We highlight that anthropogenic activities that influence soil properties and gross N production rates likely interact with future climate changes and land uses to affect soil N immobilization and, eventually, the fate of the anthropogenic reactive N.
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Affiliation(s)
- Ahmed S Elrys
- School of Geography, Nanjing Normal University, Nanjing, China
- Soil Science Department, Faculty of Agriculture, Zagazig University, Zagazig, Egypt
| | - Zhaoxiong Chen
- School of Geography, Nanjing Normal University, Nanjing, China
| | - Jing Wang
- College of Forestry, Nanjing Forestry University, Nanjing, China
| | - Yves Uwiragiye
- College of Natural Resources and Environment, Northwest A&F University, Yangling, China
- Department of Agriculture, Faculty of Agriculture, Environmental Management and Renewable Energy, University of Technology and Arts of Byumba, Byumba, Rwanda
| | - Ayman M Helmy
- Soil Science Department, Faculty of Agriculture, Zagazig University, Zagazig, Egypt
| | - El-Sayed M Desoky
- Botany Department, Faculty of Agriculture, Zagazig University, Zagazig, Egypt
| | - Yi Cheng
- School of Geography, Nanjing Normal University, Nanjing, China
- Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing, China
- Jiangsu Engineering Research Center for Soil Utilization & Sustainable Agriculture, Nanjing, China
| | - Jin-Bo Zhang
- School of Geography, Nanjing Normal University, Nanjing, China
| | - Zu-Cong Cai
- School of Geography, Nanjing Normal University, Nanjing, China
| | - Christoph Müller
- Institute of Plant Ecology, Justus Liebig University Giessen, Giessen, Germany
- School of Biology and Environmental Science and Earth Institute, University College Dublin, Dublin, Ireland
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