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Exploring suitability for tropical crop cultivation in Hainan Island by SOTAL methodology

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Journal of Geographical Sciences 2001年第4期11卷 40-46页

作者： Zhang Xue-lei S.Mantel Zhang Gan-lin V.W.P.van Engelen Institute of soil Science CASNanjing 210008China international soil reference and information centre AJ Wageningen353-6700Netherlands)

A SOTER-based automatic procedure for qualitative land evaluation is developed. This procedure was created in the automated land evaluation system (ALES). The objective was to design a procedure that allows for a quick separation of potentially suitable from non-suitable SOTER units for the intended land use, indicating constraints to different kinds of land use. Different kinds of land are unequal1y suited to various uses, land eva1uation is the assessment of the suitability of a tract of land for a specified kind of land use. In practice this implicates the comparison (matching) between the requirements of a specified land use and the properties of the land. Land evaluation concepts and definitions are treated in the paper. The ALES is a computer program that allows land evaluators to build their own knowledge-based system with which they can compute the physical and economical suitability of map units in accordance with FAO framework for land evaluation. The ALES program works with so-called decision trees, being hierarchical multiway keys in which the leaves are results (e.g., severity levels of land qualities), and the interior nodes of the tree are decision criteria (e.g., land characteristic values). These trees are traversed by the program to compute an evaluation using actual land data for each map unit. SOTAL is a SOTER-based qualitative model developed in ALES for physical land evaluation in which presently three land utilization types (LUTs) are distinguished, i.e., cultivated banana, coffee and rubber under different input and technological conditions. These LUTs are characterized by 11 landuse requirements and evaluated by matching the land use requirements with the corresponding land qualities. The paper elaborates on the criteria used in SOTAL for land quality assessment and how a final suitability rating is achieved on the basis of the rated land qualities. Results are visualized through G1S-generated maps as products in response to the specific inf

关键词： evaluation tropical crops HaiSOTER Hainan Island

Remote sensing and its applications using GNSS reflected signals:advances and prospects

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Satellite Navigation 2024年第1期5卷 10-51页

作者： Shuanggen Jin Adriano Camps Yan Jia Feng Wang Manuel Martin-Neira Feixiong Huang Qingyun Yan Shuangcheng Zhang Zhongyu Li Komi Edokossi Dongkai Yang Zhiyu Xiao Zhongmin Ma Weihua Bai Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai200030China School of Surveying and Land information Engineering Henan Polytechnic UniversityJiaozuo454003China Department of Signal Theory and Communications Technical University of CataloniaBarcelona08034Spain Department of Surveying and Geoinformatics Nanjing University of Posts and TelecommunicationsNanjing210023China School of Electronics and information Engineering Beihang UniversityBeijing100191China European Space Research and Technology centre(ESTEC) European Space Agency2200-AGNoordwijkThe Netherlands National Space Science Center Chinese Academy of SciencesBeijing100190China School of Remote Sensing and Geomatics Engineering Nanjing University of Information Science and TechnologyNanjing210044China College of Geological Engineering and Geomatics Chang’an UniversityXi’an710054China University of Electronic Science and Technology of China Chengdu611731China

The Global Navigation Satellite Systems(GNSS),including the US’s GPS,China’s BDS,the European Union’s Galileo,and Russia’s GLONASS,offer real-time,all-weather,any-time,anywhere and high precision observations by transmitting L band signals continuously,which have been widely used for positioning,navigation and *** the development of GNSS technology,it has been found that GNSS-reflected signals can be used to detect Earth’s surface characteristics together with other signals of *** this paper,the current status and latest advances are presented on Global Navigation Satellite System-Reflectometry(GNSS-R)in theory,methods,techniques and *** developments and progresses in GNSS-R instruments,theoretical modeling,and signal processing,ground and space-/air-borne experiments,parameters retrieval(*** speed,sea surface height,soil moisture,ice thickness),sea surface altimetry and applications in the atmosphere,oceans,land,vegetation,and cryosphere are given and reviewed in ***,the challenges in the GNSS-R development of each field are also ***,the future applications and prospects of GNSS-R are discussed,including multi-GNSS reflectometry,new GNSS-R receivers,GNSS-R missions,and emerging applications,such as mesoscale ocean eddies,ocean phytoplankton blooms,microplastics detection,target recognition,river flow,desert studies,natural hazards and landslides monitoring.

关键词： GNSS Reflectometry Remote sensing Environmental change

Statistical analysis of nitrogen use efficiency in Northeast China using multiple linear regression and Random Forest

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Journal of Integrative Agriculture 2022年第12期21卷 3637-3657页

作者： LIU Ying-xia Gerard B.M.HEUVELINK Zhanguo BAI HE Ping JIANG Rong HUANG Shaohui XU Xin-peng Key Laboratory of Plant Nutrition and Fertilizer Ministry of Agriculture and Rural Affairs/Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081P.R.China soil Geography and Landscape Group Wageningen UniversityWageningen 6700 AAThe Netherlands international soil reference and information centre-World soil information Wageningen 6700 AJThe Netherlands

Understanding the spatial-temporal dynamics of crop nitrogen(N)use efficiency(NUE)and the relationship with explanatory environmental variables can support land-use management and ***,the application of statistical models for evaluating the explanatory variables of space-time variation in crop NUE is still *** this study,stepwise multiple linear regression(SMLR)and Random Forest(RF)were used to evaluate the spatial and temporal variation of NUE indicators(i.e.,partial factor productivity of N(PFPN);partial nutrient balance of N(PNBN))at county scale in Northeast China(Heilongjiang,Liaoning and Jilin provinces)from 1990 to *** variables included agricultural management practices,topography,climate,economy,soil and crop *** revealed that the PFPN was higher in the northern parts and lower in the center of the Northeast China and PNBN increased from southern to northern parts during the 1990–2015 *** NUE indicators decreased with time in most counties during the study *** model efficiency coefficients of the SMLR and RF models were 0.44 and 0.84 for PFPN,and 0.67 and 0.89 for PNBN,*** RF model had higher relative importance of soil and climatic covariates and lower relative importance of crop covariates compared to the SMLR *** planting area index of vegetables and beans,soil clay content,saturated water content,enhanced vegetation index in November&December,soil bulk density,and annual minimum temperature were the main explanatory variables for both NUE *** is the first study to show the quantitative relative importance of explanatory variables for NUE at a county level in Northeast China using RF and *** novel study gives reference measurements to improve crop NUE which is one of the most effective means of managing N for sustainable development,ensuring food security,alleviating environmental degradation and increasing farmer’s profitability.

关键词： partial factor productivity of N partial nutrient balance of N stepwise multiple linear regression Random Forest county scale Northeast China

Role of land-atmosphere coupling in persistent extreme climate events in eastern China in summer 2022

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Atmospheric and Oceanic Science Letters 2024年第2期17卷 19-26页

作者： Yue Chen Aihui Wang Nansen-Zhu international Research centre Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD) Nanjing University of Information Science&TechnologyNanjingChina

2022年暖季,中国东部地区遭受持续性高温,少雨和土壤干旱的复合极端事件.特征分析指出,在研究时段内,中国东部地区的气温,降水和土壤湿度呈现明显的季节内变化和南北差异。由1940-2022年的气候态可知,长江流域和东南地区的土壤含水充足... 详细信息

2022年暖季,中国东部地区遭受持续性高温,少雨和土壤干旱的复合极端事件.特征分析指出,在研究时段内,中国东部地区的气温,降水和土壤湿度呈现明显的季节内变化和南北差异。由1940-2022年的气候态可知,长江流域和东南地区的土壤含水充足,蒸散主要受限于陆面有效能量.然而,潜在机制研究指出,2022年土壤湿度对蒸散的限制作用在上述区域异常偏强,土壤湿度与气候要素之间的强反馈可能在2022年复合极端事件的演变和持续中发挥了关键作用。

关键词：复合极端事件陆气耦合土壤湿度干旱中国东部

Digital Earth from vision to practice:making sense of citizen-generated content

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international Journal of Digital Earth 2012年第5期5卷 398-416页

作者： M.Craglia F.Ostermann L.Spinsanti Digital earth and reference data unit european commission joint research centreispraitaly

The vision of Digital Earth(DE)put recently forward under the auspices of the international Society for DE extends the paradigm of spatial data infrastructures by advocating an interactive and dynamic framework based on near-to-real time information from sensors and *** paper contributes to developing that vision and reports the results of a two-year research project exploring the extent to which it is possible to extract information useful for policy and science from the large volumes of messages and photos being posted daily through social *** the noted concerns about the quality of such data in relation to that provided by authoritative sources,the research has developed a semi-automatic workflow to assess the fitness for purpose of data extracted from Twitter and Flickr,and compared them to that coming from official sources,using forest fires as a case *** findings indicate that we were able to detect accurately six of eight major fires in France in the summer of 2011,with another four detected by the social networks but not reported by our official source,the European Forest Fire information *** findings and the lessons learned in handling the very large volumes of unstructured data in multiple languages discussed in this study provide useful insights into the value of social network data for policy and science,and contribute to advancing the vision of DE.

关键词： Digital Earth social networks volunteered geographic information data quality

Pollutant and soil Types Influence Effectiveness of soil-Applied Absorbents in Reducing Rice Plant Uptake of Persistent Organic Pollutants

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Pedosphere 2017年第3期27卷 537-547页

作者： LIU Cuiying JIANG Xin MA Yuchun Barbara J.CADE-MENUN Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Jiangsu Key Laboratory of Agricultural Meteorology College of Applied Meteorology Nanjing University of Information Science and Technology State Key Laboratory of soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Agriculture and Agri-Food Canada Semiarid Prairie Agricultural Research Centre

Persistent organic pollutants （POPs） in soils are an environmental concern due to their long-term bioavailability, which could be reduced by adding adsorbents. However, testing of these adsorbents is necessary prior to widespread field application. The effects of three adsorbents, nano-organic montmorillonite, nano-organic silicon dioxide （SiOs）, and activated carbon, on hexachlorobenzene （HCB） and pentachlorobenzene （PeCB） accumulation in rice （Oryza sativa L.） plants were tested in a greenhouse experiment using two soils, a Hydragric Acrisol （Ac） and a Gleyi-Stagnic Anthrosol （An）. The bioconcentration factors （BCFs） of HCB and PeCB to rice roots were 2.3-3.7 and 2.0 3.0 times those to rice shoots, respectively. The applications of the three adsorbents decreased HCB and PeCB extractability in Ac, while only the application of activated carbon decreased their extractability in An. The bioavailability of HCB and PeCB to rice plants in Ac was higher than that in An. In Ac, the applications of nano-organic SiOs and activated carbon decreased the BCF of HCB to rice roots by 16.1% and 26.8%, respectively, whereas only the application of activated carbon decreased the BCF of PeCB to rice roots by 31.4%, compared to the control. In An, only the application of activated carbon decreased the BCFs of HCB and PeCB to rice roots by 22.9% and 18.2%, respectively, compared to the control. However, the application of nano-organic montmorillonite inhibited rice growth in both soils. The results of this study suggested that the effectiveness of adsorbents would vary with pollutant and soil types, providing a reference point for developing efficient adsorbents to reduce the ecological risk of POPs.

关键词： accumulation activated carbon bioconcentration factor hexachlorobenzene nano-materials pentachlorobenzene

Ensemble projections of climate and streamflow in a typical basin of semi-arid steppes in Mongolian Plateau of 2021-2100

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Advances in Climate Change Research 2024年第2期15卷 230-243页

作者： Hang PAN Jian-Ping TANG Liang CHENG Man-Chun LI Jiangsu Provincial Key Laboratory of Geographic information Science and Technology Nanjing UniversityNanjing 210023China School of Geography and Ocean Science Nanjing UniversityNanjing 210023China Key Laboratory of Mesoscale Severe Weather/Ministry of Education Nanjing UniversityNanjing 210023China School of Atmospheric Sciences Nanjing UniversityNanjing 210023China

The Kherlen River is the main water source for Hulun Lake,the largest lake in northern *** to reduced inflow from the Kherlen River,Hulun Lake experienced rapid shrinkage at the beginning of the 21st century,posing a serious threat to the ecological security of northern ***,there is still a significant lack of projections regarding future climate change and its hydrological response in the Kherlen River *** study analyzed the projected climate and streamflow changes in the Kherlen River basin,a vital yet vulnerable international semi-arid steppes type basin.A combination of multi-model ensemble projection techniques,and the soil and water assessment tool(SWAT)model was employed to examine the spatio-temporal changes in precipitation,temperature,streamflow,and the associated uncertainties in the *** temperature(an increase of 1.84-6.42℃)and the precipitation(an increase of 15.0-46.0 mm)of Kherlen River basin are projected to increase by 2100,leading to a rise in streamflow(1.08-4.78 m^(3) s^(-1)).The upstream of the Kherlen River exhibits remarkable increasing trends in precipitation,which has a dominant influence on streamflow of Kherlen *** increases in streamflow are observed in April,August,September,and October compared to the reference period(1971-2000).These findings suggest a partial alleviation of water scarcity in the Kherlen River,but also an increased likelihood of hydrological extreme *** projected temperature increase in the Kherlen River basin exhibits the smallest uncertainty,while more pronounced uncertainties are found in precipitation and *** spread among the results of CMIP6 models is greater than that of CMIP5 models,with lower signal-to-noise ratio(SNR)values for temperature,precipitation,and streamflow.

关键词： Climate change Flow projection Uncertainty SWAT Mongolian Plateau

Why super sandstorm 2021 in North China?

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National Science Review 2022年第3期9卷 119-127页

作者： Zhicong Yin Yu Wan Yijia Zhang Huijun Wang Key Laboratory of Meteorological Disaster Ministry of EducationJoint International Research Laboratory of Climate and Environment Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD)Nanjing University of Information Science and Technology Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai) Nansen-Zhu international Research centre Institute of Atmospheric PhysicsChinese Academy of Sciences

Severe sandstorms reoccurred in the spring of 2021 after an absence for more than 10 years in North *** dust source area,located in Mongolia,suffered destructive cooling and warming in early and late winter,which loosened the land.A lack of precipitation,excessive snow melt and strong evaporation resulted in dry soil and exiguous spring vegetation.A super-strong Mongolian cyclone developed on the bare and loose ground,and easily blew and transported large amounts of sand particles into North ***,top-ranking anomalies(sea ice shift in the Barents and Kara Sea,and sea surface temperatures in the east Pacific and northwest Atlantic) were found to induce the aforementioned tremendous climate anomalies in the dust source *** es,based on large-ensemble Coupled Model Intercomparison Project Phase 6,yield results identical to the reanalysis ***,the climate variabilities at different latitudes and synoptic disturbances jointly facilitated the strongest spring sandstorm over the last decade.

关键词： sandstorm dust source Arctic sea ice La Niña cyclone

soil and onsite nutrient conservation potential of aromatic grasses at field scale under a shifting cultivated,degraded catchment in Eastern Ghats,India

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international Journal of Sediment Research 2018年第3期33卷 340-350页

作者： Partha Pratim Adhikary Hunsur Chikkanarasimhaiah Hombegowda Dhananjay Barman Madegowda Madhu ICAR-Indian Institute of soil and Water Conservation Research Centre ICAR-Central Research Institute for Jute and Allied Fibres

Land degradation due to soil erosion is a global problem, especially on cultivated hill slopes. Economically important aromatic grasses can protect degraded hill slopes more effectively than field crops, but little information is available on their performance. This study quantifies runoff, sediment yield,enrichment ratios of soil and nutrients, and sediment-associated organic carbon and nutrients losses under three aromatic grass species: citronella(Cymbopogon nardus), lemon(Cymbopogon flexuosus), and palmarosa(Cymbopogon martini), compared with a traditional field crop, finger millet(Eleusine coracana)grown at three land slopes(4%, 8%, and 12%). It was observed that the degree of slope and type of grass both significantly influenced runoff generation. Runoff and sediment yield(SY) were significantly higher at 12% slope than at 8% and 4% slopes. Relation between rainfall and runoff were significant for all the grass species(p soil organic carbon(SOC), available nitrogen(N), phosphorus(P) and potassium(K) in the sediment were not significantly different between slopes but differed significantly between aromatic grasses and finger millet. Sediment associated nutrient load varied inversely with SY mainly because of the nutrient dissolution effect of high runoff volume. Annual loss of SOC and nutrients varied from 84.7-156.8 kg ha-1y-1for SOC, 4.38-9.18 kg ha-1y-1for available N, 0.35-0.75 kg ha-1y-1for available P, and 2.22-5.22 kg ha-1y-1for available K, with the lowest values for citronella and highest for finger millet. The study found that the aromatic grasses have greater environmental conservation values than finger millet on steep degrade

关键词： Aromatic grass Enrichment ratio Nutrient loss Runoff Sediment yield