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Relationships between soil moisture and dust emissions in a bare sandy soil of Mongolia

Particuology 2016年第5期14卷 131-137页

作者： Erdenebayar Munkhtsetseg Masato Shinoda John A. Gillies Reiji Kimura james king George Nikolich National University of Mongolia Peace Avenue 14/3 Sukhbaatar District 8 Ulaanbaatar 14191 Mongolia Nagoya University Furo-cho Chikusa-ku Nagoya 464-8601 Nagoya Japan Desert Research Institute 2215 Raggio Parkway Reno NV 89512 USA Arid Land Research Center Tottori University Hamasaka 1390 Tottori 680-0001 Japan Departement de geographie Universite de Montreal Pavilion 520 chemin de la Cote-Sainte-Catherine Montreal QC H3 C 3J7 Canada Desert Research Institute 755 E. Flamingo Road Las Vegas NV 89119. USA

This study presents experimental results of the change in threshold friction velocity and dust emission strength as a function of soil moisture content. The dust and soil moisture data were obtained from irrigated plots of a bare, sandy soil （no vegetation） situated in the Mongolian steppe. Dust flux was measured using the PI-SWERL^（R） device, while soil moisture was measured using gravimetric methods. Our results demonstrate the strong controlling effects of soil moisture on both the threshold friction velocity and dust emission strengths. Threshold friction velocity increased from 0.44 m/s for dry soil （0.002 g/g） to 0.67 m/s for wet soil （0.06 g/g）, confirming the importance of soil moisture for controlling dust events. Dust emission strength was significantly depressed for wet soils, starting at a soil moisture value of 0.02 g/g. From these results, we developed a simple dust diagram that may be useful as part of a warning system to identify initial sensitivity to threshold conditions as well as conditions that could lead to potentially significant dust emissions. Overall, the research findings in this study could be used to provide foreknowledge of conditions that would be conducive to high dust emissions for this area of Mongolia.

关键词： Threshold friction velocity Simple dust diagram Dust emission Absence of vegetation Mini wind tunnel

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Comparison of performance of statistical models in forecasting monthly streamflow of Kizil River,China

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Water Science and Engineering 2010年第3期3卷 269-281页

作者： Shalamu ABUDU Chun-liang CUI james Phillip king Kaiser ABUDUKADEER Xinjiang Water Resources Research Institute Urumqi 830049 P. R. China Civil Engineering Department New Mexico State University NM 88001 USA Xinjiang Water Resources Bureau Urumqi 830000 P. R. China

This paper presents the application of autoregressive integrated moving average （ARIMA）, seasonal ARIMA （SARIMA）, and Jordan-Elman artificial neural networks （ANN） models in forecasting the monthly streamflow of the Kizil River in Xinjiang, China. Two different types of monthly streamflow data （original and deseasonalized data） were used to develop time series and Jordan-Elman ANN models using previous flow conditions as predictors. The one-month-ahead forecasting performances of all models for the testing period （1998-2005） were compared using the average monthly flow data from the Kalabeili gaging station on the Kizil River. The Jordan-Elman ANN models, using previous flow conditions as inputs, resulted in no significant improvement over time series models in one-month-ahead forecasting. The results suggest that the simple time series models （ARIMA and SARIMA） can be used in one-month-ahead streamflow forecasting at the study site with a simple and explicit model structure and a model performance similar to the Jordan-Elman ANN models.

关键词： time series model Jordan-Elman artificial neural networks model monthly streamflow forecasting

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Application of snowmelt runoff model(SRM) in mountainous watersheds:A review

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Water Science and Engineering 2012年第2期5卷 123-136页

作者： Shalamu ABUDU Chun-liang CUI Muattar SAYDI james Phillip king Xinjiang Water Resources Research Institute Urumqi 830049P.R.China Civil Engineering Department New Mexico State University Las CrucesNM 88001USA

The snowmelt runoff model （SRM） has been widely used in simulation and forecast of streamflow in snow-dominated mountainous basins around the world. This paper presents an overall review of worldwide applications of SRM in mountainous watersheds, particularly jn data-sparse watersheds of northwestern China. Issues related to proper selection of input climate variables and parameters, and determination of the snow cover area （SCA）using remote sensing data in snowmelt runoff modeling are discussed through extensive review of literature. Preliminary applications of SRM in northwestern China have shown that the model accuracies are relatively acceptable although most of the watersheds lack measured hydro-meteorological data. Future research could explore the feasibility of modeling snowmelt runoff in data-sparse mountainous watersheds in northwestern China by utilizing snow and glacier cover remote sensing data, geographic information system （GIS） tools, field measurements, and innovative ways of model parameterization.

关键词： snowmelt runoff model temperature precipitation snow cover area remote sensing northwestern China

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Integration of aspect and slope in snowmelt runoff modeling in a mountain watershed

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Water Science and Engineering 2016年第4期9卷 265-273页

作者： Shalamu Abudu Zhu-ping Sheng Chun-liang Cui Muatter Saydi Hamed-Zamani Sabzi james Phillip king Texas A&M AgriLife Research and Extension Center at El Paso El Paso TX 79927-5020 USA Xinjiang Water Resources Research Institute Urumqi 830049 China Civil Engineering Department New Mexico State University Las Cruces NM 88003-8006 USA

This study assessed the performances of the traditional temperature-index snowmelt runoff model(SRM) and an SRM model with a finer zonation based on aspect and slope(SRM + AS model) in a data-scarce mountain watershed in the Urumqi River Basin,in Northwest *** proposed SRM + AS model was used to estimate the melt rate with the degree-day factor(DDF) through the division of watershed elevation zones based on aspect and *** simulation results of the SRM + AS model were compared with those of the traditional SRM model to identify the improvements of the SRM + AS model's performance with consideration of topographic features of the *** results show that the performance of the SRM + AS model has improved slightly compared to that of the SRM *** coefficients of determination increased from 0.73,0.69,and 0.79 with the SRM model to 0.76,0.76,and 0.81 with the SRM + AS model during the simulation and validation periods in 2005,2006,and 2007,*** proposed SRM + AS model that considers aspect and slope can improve the accuracy of snowmelt runoff simulation compared to the traditional SRM model in mountain watersheds in arid regions by proper parameterization,careful input data selection,and data preparation.

关键词： Snowmelt runoff model (SRM) Degree-day factor (DDF) Aspect and slope Snow cover area Temperature Precipitation

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镁盐改性生物质炭的合成及其在废水氮磷资源化中的应用研究

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环境科学学报 2018年第11期38卷 4383-4390页

作者： james king′ori Njuguna 张荣斌李远王学江王健赵建夫同济大学环境科学与工程学院污染控制与资源化研究国家重点实验室上海200092 嘉兴市联合污水处理有限责任公司嘉兴314001 郑州大学水利与环境学院郑州450001

通过直接沉淀-热改性法将纳米氢氧化镁晶体(Mg(OH)_2)负载在生物质炭(BC)上,系统研究了该改性材料(Mg(OH)_2-BC)对模拟废水中氮、磷的固定特性,并探讨了投加量、反应溶液pH、接触时间对吸附过程的影响.结果表明,Mg(OH)_2-BC在投加量为0.... 详细信息

通过直接沉淀-热改性法将纳米氢氧化镁晶体(Mg(OH)_2)负载在生物质炭(BC)上,系统研究了该改性材料(Mg(OH)_2-BC)对模拟废水中氮、磷的固定特性,并探讨了投加量、反应溶液pH、接触时间对吸附过程的影响.结果表明,Mg(OH)_2-BC在投加量为0.3 g·L^(-1),反应溶液初始pH为7,反应时间≥40 min时对氮、磷的固定效果最佳,最大吸附量分别达到58.8、130.0 mg·g^(-1).Mg(OH)_2-BC对氮、磷的吸附过程均符合准二级动力学模型,吸附过程受化学吸附机理的控制.通过SEM、XRD、FTIR等对反应产物进行表征分析,结果表明,Mg(OH)_2-BC对氮、磷的固定机制主要为鸟粪石结晶沉淀,也即化学沉淀.

关键词：改性生物质炭氮磷回收资源化鸟粪石法

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Factors controlling the spatial and temporal variability of dust emissions

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Chinese Journal Of Geochemistry 2006年第B8期25卷 219-220页

作者： John A. Gillies William G. Nickling Vicken Etyemezian james king Mark Sweeney Division of Atmospheric Sciences Desert Research Institute Reno Nevada USA Wind Erosion Laboratory Department of Geography University of Guelph Guelph Ontario Canada Division of Atmospheric Sciences Desert Research Institute Las Vegas Nevada USA Department of Earth Sciences University of South Dakota Rapid City South Dakota USA

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Geophysical and Hydrogeological Groundwater Prospectivity Mapping in the Kraaipan Granite-Greenstone Terrain, Southeast Botswana

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Journal of Water Resource and Protection 2017年第11期9卷 1270-1298页

作者： Rubeni T. Ranganai Moikwathai D. Moidaki james G. king Zibisani B. Bagai Department of Physics University of Botswana Gaborone Botswana Department of Geology University of Botswana Gaborone Botswana

Application of regional geophysical methods for hydrogeological purposes has increased over the last two decades especially in arid and semi-arid areas. A project to map the Kraaipan granite-greenstone terrain in southeast Botswana has recently been undertaken using regional aeromagnetic and gravity data with the aim to map the rocks at depth to understand the geology while the secondary objective was to subsequently assess the mineralization and groundwater potential in the area. An integrated analysis of the aeromagnetic and gravity data and their derived/processed products is hereby investigated for groundwater for drinking and agricultural purposes. The studies include: subsurface characterisation and delineation of structural framework suitable for groundwater exploration and determination of petrophysical relationships used to link the geophysical properties (e.g., density) to hydrological properties (e.g., porosity). The results of interpretation indicate that the rocks are under ~50 m of Kalahari cover and the study area is composed of three aquifers: the extensive hard rock aquifer (granitic and volcanic), the important (fractured) karst aquifer and the minor sedimentary aquifer. The area is dissected by an ENE-to-EW-trending dyke swarm visible on the regional aeromagnetic data and much clearer on high resolution aeromagnetic data. Minor fault and/or dyke elements of NW-SE and NE-SW trend are observed. Spectral analysis reveals three main average ensample interfaces at depths of 0.7 km, 1.99 km and 4.8 km. The linear Euler solutions maps reveal that the majority depths to top of magnetic bodies range from 40 m to 400 m throughout the survey area. The shallowest depths are the most significant one in this case as they probably relate to depth of bedrock and thickness of regolith or thickest sediments. For 2695 existing boreholes analysed, maximum borehole depth is 482 m (mean 108 m), and almost half (1263) were dry with another 972 having low yield (1 - 5 m3