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Response of Saline-alkali Cropland Soil CO_(2)Fluxes to Nitrogen Fertilization,Irrigation and Temperature via DAYCENT Modeling
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作者 Peng ZHANG Hanxiao FENG +2 位作者 liming lai Haiwei WANG Yang YANG 《Agricultural Biotechnology》 2025年第3期56-63,共8页
A growing global demand exists to formulate plans to lessen the greenhouse gas emissions produced by agricultural activities.The purpose of this study was to uncovered the changes in soil CO_(2)fluxes under varying sc... A growing global demand exists to formulate plans to lessen the greenhouse gas emissions produced by agricultural activities.The purpose of this study was to uncovered the changes in soil CO_(2)fluxes under varying scenarios including nitrogen fertilization rates,irrigation rates,and air temperatures in the Hetao Irrigation District(HID)over the 38-year period.DAYCENT model was used to predict carbon dioxide(CO_(2))fluxes from cultivated soils in the HID,Inner Mongolia from^(2)023 to 2060(the year of achieving the"carbon neutrality"goal)in this study.Results showed that mean soil CO_(2)fluxes in the sunflower field[1035.13 g/(m^(2).yr)]were significantly lower than those in the maize field[1405.54 g/(m^(2).yr)].An increase in nitrogen fertilization rate led to a significant escalation in soil CO_(2)fluxes.Moreover,elevating irrigation rates for washing salts by irrigation(WSBI)diminished soil CO_(2)fluxes in the sunflower field while amplifying them in the maize field.A rise in air temperature resulted in an increase in soil CO_(2)fluxes from the maize field,with annual increases observed,but a reduction in soil CO_(2)fluxes from the sunflower field.The sunflower fields in the HID have a more substantial advantage than the corn fields in mitigating soil CO_(2)emissions. 展开更多
关键词 Soil CO_(2)flux Nitrogen fertilization rate SUNFLOWER Washing salts by irrigation Rising temperature DAYCENT model Hetao Irrigation District
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Characteristics and Development of Agricultural Soil in Hetao Irrigation District,Inner Mongolia 被引量:2
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作者 Yang YANG liming lai Li MEI 《Agricultural Biotechnology》 CAS 2022年第4期77-82,共6页
Hetao Irrigation District is located in the cold and arid region of Hetao Plain,Inner Mongolia,where the agricultural soil has unique characteristics.Although the agricultural soil properties in Hetao Irrigation Distr... Hetao Irrigation District is located in the cold and arid region of Hetao Plain,Inner Mongolia,where the agricultural soil has unique characteristics.Although the agricultural soil properties in Hetao Irrigation Districts have been reported,the overall characteristics remain unclear.Through literature review and investigation,the overall characteristics,development patterns,and related reasons were explored,consequently providing theoretical support for enhancing soil utilization and formulating sustainable soil development strategies.The results showed that the agricultural soil in Hetao Irrigation District originated from the sedimentary layer and anthropogenic mellowing produced by the diversions of the Yellow River.The soil has periodic secondary salinization characteristics,accompanied by a slightly increasing pH value over time.It has low soil organic contents with a stable changing trend,low nitrogen,and phosphorus contents but high potassium and sulfur content,uneven nutrient distribution,diverse production performance,weak but stable ecological performance,and heterogeneous soil quality with a stable change trend.These findings indicate that this kind of soil can be used to plant diverse crops tolerant to different saline-alkali and requiring various nutrients.This agricultural soil is sustainable,but it is also faced with the problems of increased saline-alkali,nutrient loss,and pollution. 展开更多
关键词 Agricultural soil Secondary salinization Organic matter Soil nutrients HETEROGENEITY Ecological features Hetao Irrigation District
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Modeling the impacts of temperature and precipitation changes on soil CO_2 fluxes from a Switchgrass stand recently converted from cropland 被引量:2
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作者 liming lai Sandeep Kumar +6 位作者 Rajesh Chintala Vance N. Owens David Clay Joseph Schumacher Abdul-Sattar Nizami Sang Soo Lee Rashad Rafique 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2016年第5期15-25,共11页
Switchgrass(Panicum virgatum L.) is a perennial C_4 grass native to North America and successfully adapted to diverse environmental conditions. It offers the potential to reduce soil surface carbon dioxide(CO_2) f... Switchgrass(Panicum virgatum L.) is a perennial C_4 grass native to North America and successfully adapted to diverse environmental conditions. It offers the potential to reduce soil surface carbon dioxide(CO_2) fluxes and mitigate climate change. However, information on how these CO_2 fluxes respond to changing climate is still lacking. In this study, CO_2 fluxes were monitored continuously from 2011 through 2014 using high frequency measurements from Switchgrass land seeded in 2008 on an experimental site that has been previously used for soybean(Glycine max L.) in South Dakota, USA. DAYCENT, a process-based model, was used to simulate CO_2 fluxes. An improved methodology CPTE[Combining Parameter estimation(PEST) with "Trial and Error" method] was used to calibrate DAYCENT. The calibrated DAYCENT model was used for simulating future CO_2 emissions based on different climate change scenarios. This study showed that:(i) the measured soil CO_2 fluxes from Switchgrass land were higher for 2012 which was a drought year, and these fluxes when simulated using DAYCENT for long-term(2015–2070) provided a pattern of polynomial curve;(ii) the simulated CO_2 fluxes provided different patterns with temperature and precipitation changes in a long-term,(iii) the future CO_2 fluxes from Switchgrass land under different changing climate scenarios were not significantly different, therefore, it can be concluded that Switchgrass grown for longer durations could reduce changes in CO_2 fluxes from soil as a result of temperature and precipitation changes to some extent. 展开更多
关键词 Carbon dioxide Switchgrass DAYCENT Climate change
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Impacts of Sulfur and Microalgae Co-fertilization on Saline-alkaline Soil of Sunflower Field in Hetao Irrigation District
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作者 Ruimin DONG liming lai +5 位作者 Peng ZHANG Yanxiong ZHAO Yang YANG Haiwei WANG Man WANG Yuelong DONG 《Asian Agricultural Research》 2023年第3期30-33,36,共5页
[Objectives]To evaluate the impacts of the elemental sulfur(S 0)and micro-algae(MA)co-fertilization on saline-alkaline soil of sunflower field in the Hetao Irrigation District(HID).[Methods]The greenhouse pot experime... [Objectives]To evaluate the impacts of the elemental sulfur(S 0)and micro-algae(MA)co-fertilization on saline-alkaline soil of sunflower field in the Hetao Irrigation District(HID).[Methods]The greenhouse pot experiment was conducted with four treatments:control(CK),single S 0 fertilization(S),single MA fertilization(A),and S 0 and MA co-fertilization(SA)for comparing the selected soil properties and sunflower plant heights and weights in different treatments.[Results]The results showed that the mean soil organic matter(SOM)under the SA(25.08 g/kg)was significantly higher than that for the CK(20.59 g/kg),S(22.47 g/kg),and A(22.95 g/kg).The mean pH under the SA(7.75)was significantly lower than that for the CK(8.14),S(7.82),and A(7.96).The mean soil exchangeable Na+concentration under the SA was significantly lower than that for the S.The mean soil electrical conductivity(EC)under the SA was 9.76%lower than that for the S.The means of Cl-(1.22 g/kg)and SO 2-4(1.90 g/kg)in soil under the SA were lower than that for the S(1.30,2.06 g/kg)and A(1.31,1.97 g/kg),respectively.For plant height 3 at the late stage of plant growth,the mean plant height 3 under the SA(89.00 cm)was higher than that of the CK(69.60 cm)and A(74.33 cm).The total weights of the fresh sunflower heads,fresh stems,and dry seeds under the SA were higher than that for the CK,S,and A.[Conclusions]In conclusion,the S 0 and MA co-fertilization had positive effects on improving saline-alkaline soils,the soil under the S 0 and MA co-fertilization could be better conditions for promoting sunflower growth than that for the S,Z,and CK,and thereby the S 0 and MA co-fertilization could be a new idea to improve saline-alkaline soil in the cold and arid regions. 展开更多
关键词 Sulfur and microalgae co-fertilization SUNFLOWER Saline-alkaline soil Hetao Irrigation District(HID)
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An Empirical Framework of Washing Salinity by Irrigation to Maintain Soil Quality in Hetao Irrigation District
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作者 Xueao GAO liming lai +2 位作者 Ning LI Yang YANG Haiwei WANG 《Asian Agricultural Research》 2022年第9期28-34,共7页
[Objectives] To summarize the characteristics of washing salinity by irrigation in Hetao Irrigation District, and propose the empirical framework of washing salinity by irrigation to maintain soil quality, and provide... [Objectives] To summarize the characteristics of washing salinity by irrigation in Hetao Irrigation District, and propose the empirical framework of washing salinity by irrigation to maintain soil quality, and provide a theoretical basis for maintaining the sustainable development of soil in Hetao Irrigation District. [Methods] The methods of experiment, questionnaire, on-the-spot investigation and literature review were used. [Results] This study proposed the empirical framework of washing salinity by irrigation to maintain soil quality in Hetao Irrigation District. Seven factors of the framework, including flood irrigation, land leveling, plastic film mulching, fertilization, soil organic matter, pH and salinity, and their relationships were determined. The characteristics of these factors in Hetao Irrigation District were investigated(flooding irrigation with a large amount of irrigation water, high amount of fertilizer application, low organic matter, high pH, large variation of salinity, etc.). The mechanisms and effects of various factors affecting soil quality in Hetao Irrigation District were analyzed(the mean soil organic matter(SOM) and pH were kept in the range of 10.9-13.9 g/kg and 8.0-8.15 in recent 35 years, respectively, and increased slightly, etc.). [Conclusions] The empirical framework can be used as a theoretical norm for evaluating soil quality under the condition of washing salinity by irrigation. Under the condition of washing salinity by irrigation, the agricultural soil quality in Hetao Irrigation District showed a stable trend over time. Using this framework, we can find soil problems, and adjust some unbalanced factors to maintain the stability of soil quality in Hetao Irrigation District, and can also provide a reference for other areas. 展开更多
关键词 Washing salinity by irrigation Empirical framework Soil quality Hetao Irrigation District
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基于机器学习和经验知识的青藏高原多时段植被制图 被引量:1
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作者 周继华 来利明 +9 位作者 陈巧娥 宋长青 高培超 叶思菁 沈石 杨刚刚 郝海霞 王贵豪 熊喆 郑元润 《科学通报》 北大核心 2025年第1期134-144,共11页
理解植被长期演变趋势及其对气候变化与人类活动的响应需要多时段植被分布资料.目前青藏高原植被图主要为2000、2020年前后两个时段,以及1990~2020年时段;主要是基于地面调查数据的人工制图以及基于地面调查数据、遥感数据、地形与气候... 理解植被长期演变趋势及其对气候变化与人类活动的响应需要多时段植被分布资料.目前青藏高原植被图主要为2000、2020年前后两个时段,以及1990~2020年时段;主要是基于地面调查数据的人工制图以及基于地面调查数据、遥感数据、地形与气候资料,采用机器学习模型分类的自动制图,存在部分植被类型混淆、制图精度有待提高等问题,同时,缺乏更早时段的植被分布资料.本文发展了整合地面调查数据、遥感数据、地形数据、气候数据等,基于随机森林机器学习模型的人工制图技术,获得了1980s、2020年青藏高原植被分布图;基于植被地带性分析和1980s植被图,获得青藏高原近似复原植被图;以2020年青藏高原植被图为基础,采用随机森林模型模拟了2035、2050年青藏高原植被分布图.近似复原植被图、1980S和2020年青藏高原植被图的空间分辨率可达到100 m,与公认较为可靠的《中华人民共和国植被图(1:100万)》相比,本研究获得的1980s和2020年植被图对植被类型边界的刻画更为准确,植被斑块数目增加较多,有利于更加准确理解和模拟青藏高原植被对气候变化的响应. 展开更多
关键词 青藏高原 植被制图 机器学习模型 多源数据 植被分类
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Organic dye assemblies with aggregation-induced photophysical changes and their bio-applications 被引量:2
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作者 Chendong Ji liming lai +3 位作者 Pengyu Li Zhen Wu Wenyu Cheng Meizhen Yin 《Aggregate》 2021年第4期57-71,共15页
Phototheranostics provide a safe,effective,and noninvasive way for the diagnosis and treatment of contemporary diseases,and organic dyes play a vital role.For example,chemical modification endowed dyes with powerful r... Phototheranostics provide a safe,effective,and noninvasive way for the diagnosis and treatment of contemporary diseases,and organic dyes play a vital role.For example,chemical modification endowed dyes with powerful reactive oxygen species or heat generation ability,favoring for photodynamic therapy and photoacoustic(PA)imaging guided photothermal therapy(PTT)of serious diseases.Therefore,photophysical properties manipulation of dyes has become the focus in current dye chemistry research.The development of aggregate science has made great effort to solve this problem.In recent years,a large number of studies have focused on molecular aggregation behavior and its effect on photophysical performance.The most famous example is the discovery of aggregation-induced emission(AIE)phenomenon.Based on AIE theory,more theories for revealing the relationship between molecular aggregation behavior and photophysical properties were proposed and elucidated.The photophysical property changes caused by dye aggregation have become a unique discipline,guiding the development of molecular science and material science.With the help of molecular self-assembly,controllable aggregation of dyes can be realized,and stable nano-theranostic reagents can be obtained.Furthermore,constructing dye assemblies with various photophysical properties will greatly reduce the cost of theranostic reagents,thus,expanding biomedical applications of organic dyes.Therefore,this review focuses on the photophysical characteristic changes caused by dye aggregation and their biological applications including,fluorescence/phosphorescence/PA imaging as well as photodynamic and PTT.This review will provide guidance for the design of organic dyes,the development of controllable aggregation methods,and the construction of multifunctional phototheranostic reagents. 展开更多
关键词 aggregation-induced photophysical changes fluorescence imaging organic dye assemblies PHOSPHORESCENCE photodynamic therapy photothermal therapy
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