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Frontiers of Agricultural Science and Engineering 2022年第3期9卷 407-424页

作者： Jianlin SHEN Yong LI Yi WANG Yanyan LI Xiao ZHU Wenqian JIANG Yuyuan LI Jinshui WU Key Laboratory of Agro-ecological Processes in Subtropical Region and Changsha Research Station for Agricultural&Environmental Monitoring Institute of Subtropical AgricultureChinese Academy of SciencesChangsha 410125China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Resources and Environmental Engineering Ludong UniversityYantai 264025China

The subtropical hilly region of China is a region with intensive crop and livestock production,which has resulted in serious N pollution in soil,water and air.This review summarizes the major soil N cycling processes and their influencing factors in rice paddies and uplands in the subtropical hilly region of China.The major N cycling processes include the N fertilizer application in croplands,atmospheric N deposition,biological N fixation,crop N uptake,ammonia volatilization,N_(2)O/NO emissions,nitrogen runoff and leaching losses.The catchment nutrients management model for N cycle modeling and its case studies in the subtropical hilly region were also introduced.Finally,N management practices for improving N use efficiency in cropland,as well as catchment scales are summarized.

关键词： nitrogen cycling soil nitrogen nitrogen deposition greenhouse gases emission non-point source pollution nitrogen use efficiency

The potential for an old-growth forest to store carbon in the topsoil:A case study at Sasso Fratino,Italy

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Journal of Forestry Research 2024年第2期35卷 23-32页

作者： Tommaso Chiti Nicola Benilli Giovanni Mastrolonardo Giacomo Certini Dipartimento per la Innovazione nei Sistemi Biologici Agroalimentari e Forestali(DIBAF)Universitàdella TusciaVia San C.de Lellis Snc01100 ViterboItaly Dipartimento di Scienze e Tecnologie Agrarie AlimentariAmbientali e Forestali(DAGRI)Universitàdegli Studi di FirenzeP.le delle Cascine 1850144 FirenzeItaly

There is considerable interest devoted to oldgrowth forests and their capacity to store carbon(C)in biomass and soil.Inventories of C stocks in old-growth forests are carried out worldwide,although there is a lack of information on their actual potential for C sequestration.To further understand this,soil organic carbon(SOC)was measured in one of Italy's best-preserved old-growth forests,the Sasso Fratino Integral Nature Reserve.This reserve is on the World Heritage List along with other ancient beech forests of Europe,and it is virtually untouched due to the steepness of the terrain,even before legal constraints were imposed.Although the sandstone-derived soils are often shallow,they are rich in organic matter.However,no quantification had been carried out.By systematically sampling the topsoil across the forest,we accurately determined the average amount of SOC(62.0±16.9 Mg ha^(–1))and nitrogen(4.0±1.2 Mg ha^(–1))in the top 20 cm.Using the CENTURY model,future dynamics of SOC stocks were predicted to 2050 according to two climate scenarios,A1F1 and B2,the first of high concern and the second more optimistic.The model projected an increase of 0.2 and 0.3 Mg ha^(–1)a^(–1)by 2030 under the A1F1 and B2 scenarios,respectively,suggesting that the topsoil in old-growth forests does not reach equilibrium but continues accumulating SOC.However,from 2030 to 2050,a decline in SOC accumulation is predicted,indicating SOC net loss at high altitudes under the worst-case scenario.This study confirms that soils in oldgrowth forests play a significant role in carbon sequestration.It also suggests that climate change may affect the potential of these forests to store SOC not only in the long term but also in the coming years.

关键词： Carbon sequestration CENTURY model Climate change Forest soil soil nitrogen

Maize straw application as an interlayer improves organic carbon and total nitrogen concentrations in the soil profile: A four-year experiment in a saline soil

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Journal of Integrative Agriculture 2023年第6期22卷 1870-1882页

作者： CHANG Fang-di WANG Xi-quan SONG Jia-shen ZHANG Hong-yuan YU Ru WANG Jing LIU Jian WANG Shang JI Hong-jie LI Yu-yi Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081P.R.China The Norwegian Institute of Bioeconomy Research(NIBIO) As 1431Norway Department of soil and Plant Microbiome Institute of PhytopathologyChristian-Albrechts-University of KielKiel 24118Germany

soil salinization is a critical environmental issue restricting agricultural production.Deep return of straw to the soil as an interlayer (at 40 cm depth) has been a popular practice to alleviate salt stress.However,the legacy effects of straw added as an interlayer at different rates on soil organic carbon (SOC) and total nitrogen (TN) in saline soils still remain inconclusive.Therefore,a four-year (2015–2018) field experiment was conducted with four levels (i.e.,0,6,12and 18 Mg ha~(–1)) of straw returned as an interlayer.Compared with no straw interlayer (CK),straw addition increased SOC concentration by 14–32 and 11–57%in the 20–40 and 40–60 cm soil layers,respectively.The increases in soil TN concentration (8–22 and 6–34%in the 20–40 and 40–60 cm soil layers,respectively) were lower than that for SOC concentration,which led to increased soil C:N ratio in the 20–60 cm soil depth.Increases in SOC and TN concentrations in the 20–60 cm soil layer with straw addition led to a decrease in stratification ratios (0–20 cm:20–60 cm),which promoted uniform distributions of SOC and TN in the soil profile.Increases in SOC and TN concentrations were associated with soil salinity and moisture regulation and improved sunflower yield.Generally,compared with other treatments,the application of 12 Mg ha~(–1) straw had higher SOC,TN and C:N ratio,and lower soil stratification ratio in the2015–2017 period.The results highlighted that legacy effects of straw application as an interlayer were maintained for at least four years,and demonstrated that deep soil straw application had a great potential for improving subsoil fertility in salt-affected soils.

关键词： straw addition interlayer soil organic carbon soil nitrogen C:N ratio saline soil

Optimized NPK fertilizer recommendations based on topsoil available nutrient criteria for wheat in drylands of China

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Journal of Integrative Agriculture 2024年第7期23卷 2421-2433页

作者： enjie Yang Jie Yu Yanhang Li Bingli Jia Longgang Jiang Aijing Yuan Yue Ma Ming Huang Hanbing Cao Jinshan Liu Weihong Qiu Zhaohui Wang Key Laboratory of Plant Nutrition and Agri-environment in Northwest China Ministry of Agriculture and Rural Affairs/College of Natural Resources and EnvironmentNorthwest A&F UniversityYangling 712100China

The optimized management of crop fertilization is very important for improving crop yield and reducing the consumption of chemical fertilizers.Critical nutrient values can be used for evaluating the nutritional status of a crop,and they reflect the nutrient concentrations above which the plant is sufficiently supplied for achieving the maximum potential yield.Based on on-farm surveys of 504 farmers and 60 field experimental sites in the drylands of China,we proposed a recommended fertilization method to determine nitrogen(N),phosphorus(P),and potassium(K)fertilizer input rates for wheat production,and then validated the method by a field experiment at 66 different sites in northern China.The results showed that wheat grain yield varied from 1.1 to 9.2 t ha^(-1),averaging 4.6 t ha^(-1),and it had a quadratic relationship with the topsoil(0-20 cm)nitrate N and soil available P contents at harvest.However,yield was not correlated with the inputs of N,P,and K fertilizers.Based on the relationship(exponential decay model)between 95–105%of the relative yield and topsoil nitrate N,available P,and available K contents at wheat harvest from 60 field experiments,the topsoil critical nutrient values were determined as 34.6,15.6,and 150 mg kg^(-1)for soil nitrate N,available P,and available K,respectively.Then,based on five groups of relative yield(>125%,115–125%,105–115%,95–105%,andsoil critical nutrient levels and fertilization coefficients(Fc)were determined.Finally,we proposed a new method for calculating the recommended fertilizer input rate as:Fr=Gy×Nr×Fc,where Fr is the recommended fertilizer(N/P/K)input rate;Gy is the potential grain yield;Nr is the N(N_(rN)),P(N_(rP)),and K(N_(rK))nutrient requirements for wheat to produce 1,000 kg of grain;and Fc is a coefficient for N(N_c)/P(P_c)/K(K_c)fertilizer.A 2-year validated experiment confirmed that the new method reduced N fertilizer input by 17.5%(38.5 kg N ha^(-1))and P fertilizer input by 43.5%(57.5 kg P_2O_5 ha^(-1))in northern

关键词： fertilization method dryland wheat soil nutrient critical value soil nitrogen topsoil nutrients

Legume Green Manure and Intercropping for High Biomass Sorghum Production

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Agricultural Sciences 2024年第6期15卷 605-621页

作者： Clark B. Neely Francis M. Rouquette Jr. Cristine L. S. Morgan Frank M. Hons William L. Rooney Gerald R. Smith Department of soil and Crop Science Washington State University Pullman WA USA Texas A&M AgriLife Research Overton TX USA soil Health Institute Morrisville NC USA Department of soil and Crop Science Texas A&M University College Station TX USA

Before the advent of cheap, synthetic fertilizers, legumes were commonly used as green manure crops for their ability to fix atmospheric nitrogen (N). A three-year study at Overton, TX examined legume integration into high-biomass sorghum (Sorghum bicolor L.) production systems on a Lilbert loamy fine sand recently cultivated after a fertilized bermudagrass [Cynodon dactylon (L.) Pers.] pasture. In this split-split plot design, ‘Dixie’ crimson clover (Trifolium incarnatum L.) and ‘Iron and Clay’ cowpea (Vigna unguiculata L.) were integrated into a high-biomass sorghum production system to evaluate impacts on N concentration, C concentration, and yield of high-biomass sorghum and their impacts on soil total N and soil organic carbon (SOC). Main plots were split into crimson clover green manure (CLGM) and winter fallow (FALL) followed by three sub-plots split into warm-season crop rotations: cowpea green manure (CPGM), cowpea-sorghum intercrop (CPSR), and sorghum monocrop (SORG). Three N fertilizer treatments (0, 45, 90 kg N∙ha−1) were randomized and applied as sub-sub plots. The CLGM increased (P sorghum biomass yield (16.5 t DM∙ha−1) 28% in year three but had no effect in the first two years. The CPSR treatment reduced sorghum yield up to 62% compared to SORG;whereas CPGM increased sorghum yield 56% and 18% the two years following cowpea incorporation. Rate of N fertilizer had no effect on sorghum biomass yield. Decrease in SOC and soil N over time indicated mineralization of organic N and may explain why no N fertilizer response was observed in sorghum biomass yield. Cowpea showed strong potential as a green manure crop but proved to be too competitive for successful intercropping in high-biomass sorghum production systems.

关键词： High-Biomass Sorghum Legumes Green Manure Intercrop Cowpea Crimson Clover soil Organic Carbon soil nitrogen

Impacts of center pivot irrigation system uniformity on growth of potato crop and residual soil nitrogen

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International Journal of Agricultural and Biological Engineering 2019年第1期12卷 126-131页

作者： Khalid A.Al-Gaadi Abdalhaleem A.Hassaballa ElKamil Tola Ahmed G.Kayad Rangaswamy Madugundu Fahad Assiri Mohamed Edrris Ahmed Alameen Haroon Edrees Precision Agriculture Research Chair(PARC) King Saud UniversityRiyadhSaudi Arabia Department of Agricultural Engineering College of Food and Agriculture SciencesKing Saud UniversityRiyadhSaudi Arabia Department of Agricultural&Biological Engineering Faculty of EngineeringUniversity of KhartoumSudan Saudi Agricultural Development Company(INMA) Wadi Al-DawasirSaudi Arabia

Maintaining the homogeneity of soil nitrogen(N)and plant vigor across agricultural fields is a major concern for farmers and agricultural scheme planners,particularly fields that are irrigated through pressurized systems,such as center pivots.Therefore,this study was carried out on a 30 hm2 potato field located 650 km south of Riyadh,the capital city of the Kingdom of Saudi Arabia,to investigate the impacts of the center pivot irrigation distribution uniformity on the crop development and the spatial distribution of residual soil N.Irrigation performance test was designed to investigate water application rate and distribution uniformities.The overall water application uniformity coefficients(Cu),determined through Christiansen(Cud)and Heerman(CuH)methods,were determined at 81.29%and 80.64%,respectively.However,the overall water distribution uniformity(Du)was determined at 70%.A considerable variability in the distribution uniformity of irrigation water was observed across the experimental field(a Du value of 67%over the medium spans compared to a Du value of 88%over the inner spans).Results of this study showed a linear correlation between the irrigation water distribution uniformity and the soil N(R^(2)=0.88).On the other hand,the vegetation cover distribution,indicated by the Cumulative Normalized Difference Vegetation Index(CNDVI),was not found to be much responsive to the irrigation distribution uniformity(R^(2)=0.11).A time series of successive NDVI maps extracted throughout the potato crop growth stages showed a consistent trend in the distribution of NDVI across the field,with R2 values that ranged between 0.25-0.73.

关键词： irrigation performance uniformity center pivot potato soil nitrogen NDVI

SIMULATION OF soil nitrogen MINERALIZATION AND NITRIFICATION IN TWO NORTHERN HARDWOOD FOREST ECOSYSTEMS

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Journal of Northeast Forestry University 1995年第2期6卷 1-13页

作者：欧阳华 Commission for Integrated Survey of Natural Resource Chinese Academy of Sciences Beijing China Michigan Technological University Houghton USA

A process-based, biological model is presented that simulates soil nitrogen (N) mineralization and nitrification in two northern hardwood forest ecosystems in the Upper Peninsula of Michigan. The soil system is divided into two compartments (forest floor and mineral soil) since quantity and quality of the organic substrate, and the important driving variables (temperature and moisture) for the model vary between these two compartments. The model focuses on the central position of microorganisms in the N mineralization and nitrification processes, and the use of multiplicative factors to account for the effect of temperature, moisture and carbon(C):N ratio on these processes.The model has been validated with data from two northern hardwood stands in the Upper Peninsula of Michigan. A close agreement between calculated and observed monthly means was obtained in both stands, especially for net N mineralization, which plays a very impormnt role in determining available N. The nitrification rates had relatively larger variation than the N mineralization rates, but the model adequately described the seasonal trends of the observed values. A simple sensitivity analysiwas performed to assess the response of the model to changes in important variables (temperature, moisture, organic N, and C:N ratio) between the two study sites. This analysis showed that increased temperature and higher organic N levels consistently increased N mineralization and nitrification in the both stands. The model's results were most sensitive to moisture changes in forest floor, but were not sensitive to moisture changes in the mineral soil. In contrast, C:N ratio was influential in the mineral soil, but did not have any effect in the forest floor.

关键词： soil nitrogen Hardwood forests Mineralization Nitrification Biologica model

Dynamic changes in soil chemical properties and microbial community structure in response to different nitrogen fertilizers in an acidified celery soil

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soil Ecology Letters 2019年第3期1卷 105-113页

作者： Yuping Wu Jiangxing Wu Yongjun Ma Ying Lian Hui Sun Danchao Xie Yaying Li Philip C.Brookes Huaiying Yao Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Ningbo Agriculture Bureau Ningbo 315012China Ningbo Institute of Standardization Ningbo 315040China Ningbo Urban Environment Observation and Research Station Chinese Academic SciencesNingbo 315830China College of Environmental and Natural Resource Sciences Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant NutritionZhejiang UniversityHangzhou 310058China

To determine the effects of different kinds of nitrogen fertilizer,especially high-efficiency slowrelease fertilizers,on soil pH,nitrogen(N)and microbial community structures in an acidic celery soil,four treatments(CK,no N fertilizer;NR,urea;PE,calcium cyanamide fertilizer;and SK,controlled-release N fertilizer)were applied,and soil pH,total soil N,inorganic N,and soil microbial biomass C were analyzed.Phospholipid fatty acids(PLFAs)were extracted and detected using the MIDI Sherlock microbial identification system.The PE treatment significantly improved soil pH,from 4.80 to>6.00,during the whole growth period of the celery,and resulted in the highest celery yield among the four treatments.After 14 d application of calcium cyanamide,the soil nitrate content significantly decreased,but the ammonium content significantly increased.The PE treatment also significantly increased soil microbial biomass C during the whole celery growth period.Canonical variate analysis of the PLFA data indicated that the soil microbial community structure in the CK treatment was significantly different from those in the N applied treatments after 49 d fertilization.However,there was a significant difference(Psoil microbial community structure between the PE treatment and the other three treatments at the end of the experiment.Calcium cyanamide is a good choice for farmers to use on acidic celery land because it supplies sufficient N,and increases soil pH,microbial biomass and the yield of celery.

关键词： Acidified Calcium cyanamide Celery Phospholipid fatty acid soil nitrogen

Yield Effect of Chemical and soil nitrogen on the Mid-season and Ratooning Hybrid Rice

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Journal of Northeast Agricultural University(English Edition) 2009年第3期16卷 17-21页

作者： BAO Lingfeng LINT Gang ZHAO Deming LI Yunwu HE Bin Agricultural Science Academy ofYibin Yibin 644000 Sichuan China

Using hybrid rice Yixiang1577 as the material, the mid-season and ratooning hybrid rice yield variation was studied in Southem Sichuan at different levels of nitrogen fertilizer. The results showed that rice yield by using N fertilizer increased to the most significant level than no fertilizer ones, and the mid-season rice and rice yield by using more N fertilizer increased to the significant level than less fertilizer ones. The rice yield by using no fertilizer ones increased to the most significant level than some used fertilizer, and the ratooning rice and rice yield by using more N fertilizer decreased to the most significant level than less fertilizer ones. The rice yield by using some fertilizer increased to the most significant level than no fertilizer ones for mid-season＋rationing rice and rice yield by using some fertilizer had no obvious differences at different nitrogen levels. Therefore, application of fertilizer can improve yield of mid-season rice and mid-season＋rationing rice. soil test results showed that nutrient contents in rice field in South Sichuan were very rich in nitrogen, which could provide more adequate crop growth potential soil nitrogen nutrition. The crops with a deep root system had stronger ability of utilization on soil nitrogen. Therefore, the ratooning rice used no or little N fertilizer had a high yield performance because they made full use of soil nitrogen with deep root system.

关键词： rice chemical nitrogen soil nitrogen yield

N_(x)O emissions in response to the irrigation lower limits under different irrigation modes in a lettuce field

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International Journal of Agricultural and Biological Engineering 2023年第4期16卷 159-166页

作者： Maomao Hou Ying Xiao Qinyuan Zhu Jingnan Chen Huan Huang Qiu Jin Lin Zhu Fenglin Zhong College of Horticulture Fujian Agriculture and Forest UniversityFuzhou 350000China Nanjing Institute of Environmental Sciences Nanjing 210000China College of Horticulture and Gardening Fujian Agricultural Vocational and Technical CollegeFuzhou 350000China Juhuang Group Co. Ltd.Xiamen 361021China Nanjing Hydraulic Research Institute Nanjing 210000China

Irrigation has a significant impact on N_(x)O(N_(2)O and NO)emissions from cultivated land,yet the N_(2)O or NO emission among the irrigation lower limits under different irrigation modes has not been well compared.In an irrigated lettuce field,three DR(drip irrigation)lower limits were designed,including 75%(DR1),65%(DR2)and 55%(DR3)field capacity,and one FI(furrow irrigation)lower limit(65%field capacity).The N_(2)O and NO emission fluxes and soil nitrogen(N)forms were determined,and the linear correlation between these indicators was analyzed.Results showed that under the same irrigation regime,the N_(2)O and NO emissions from furrow irrigation treatment increased by 36.8%and 45.2%respectively compared to that from drip irrigation treatment.The cumulative N_(2)O and NO emissions under DR3 were 30.2%and 28.6%higher than under DR1,respectively.Moreover,DR1 was also the lowest among the four treatments in soil-N concentration.The N_(2)O and NO emission fluxes were more correlated to soil NH_(4)^(+)-N(r=0.88 and 0.76)or NO_(2)^(-)-N(r=0.90 and 0.80)concentration than soil-N and soluble organic N,indicating that N_(2)O and NO were mainly produced by the soil nitrification process.When the irrigation regime was the same,N_(2)O and NO emissions were lower with drip irrigation than with furrow irrigation.Besides,drip irrigation with small quota but high frequency reduced N_(2)O and NO emission compared to that with large quota but low frequency.

关键词： nitrous oxide nitric oxide drip irrigation furrow irrigation soil nitrogen