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Journal of Forestry research 2016年第4期27卷 879-887页

作者： Guanlong Gao Xiaoyou Zhang Tengfei Yu cold and arid regions environmental and engineering research Institute Chinese Academy of Sciences

Thus far, measurements and estimations of actual evapotranspiration（ET） in extremely arid areas are still insufficient. Based on successive observations from June–September 2014, we simulated ET of a Populus euphratica Oliv. forest during the growing season in an extremely arid region of northwest China using the Shuttleworth–Wallace（S–W） model. Simulated ET values were compared to those of the eddy-covariance（EC） method on a 1 h interval. With a root mean square error（RMSE）,relative error（RE） and mean absolute error（MAE） of0.192, 3.100 and 0.165 mm h-1, respectively, model performance was not satisfactory. In particular, on days with strong winds（Sep. 11–13）, deviations between simulated and observed ET values increased to 0.275, 0.878 and0.251 mm h-1, RMSE, RE and MAE respectively. These values were significantly greater than those in other study periods and were most likely owing to sharp increases in wind speed. As a result, there were substantial advective effects, which is not consistent with the assumption of the S–W model that there are no advective effects or mesoscale circulation patterns induced by surface discontinuities.

关键词： Wallace extremely satisfactory northwest absolute season successive insufficient sharp assumption

Mapping the Risk of Water Erosion in the Watershed of the Ningxia-Inner Mongolia Reach of the Yellow River, China

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Journal of Mountain Science 2015年第1期12卷 70-84页

作者： DU He-qiang XUE Xian WANG Tao cold and arid regions environmental and engineering research Institute Chinese Academy of Sciences

Mapping and assessing soil-erosion risk can address the likelihood of occurrence of erosion as well as its consequences. This in turn provides precautionary and relevant suggestions to assist in disaster reduction. Because soil erosion by water in the watershed of the Ningxia-Inner Mongolia reach of the Yellow River is closely related to silting of the upper reaches of the Yellow River, it is necessary to assess erosion risk in this watershed. This study aims to identify the soil-erosion risk caused by water in the watershed of the Ningxia-Inner Mongolia reach of the Yellow River from 2ool to aOlO. Empirical models called Chinese Soil Loss Equation （CSLE） and Modified Universal Soil Loss Equation （MUSLE） were used to predict the erosion modulus in slope surfaces and gullies. Then the soil erosion risk in this watershed was assessed according to the classification criteria of soil erosion intensities （SL19o-2oo7）. The study results showed that the range of values of the erosion modulus in this watershed was o-44,733 t/km2/a. More than 20% of the total watershed area was found to present an erosion risk, with the regions at risk mainly located in channels and their upper reaches, and in mountainous areas. To determine the regression coefficients of the erosion factors with respect to erosion modulus, a GWR （geographically weighted regression） was carried out using the ArcGIS software. It was found that the topographic factor has the highest contribution rate to the soil erosion modulus, while the highest contribution rate of the erosion factors to the erosion modulus and the largest values of the factors were not located in the same places. Based on this result, the authors propose that slope management is the most important task in preventing soil loss in this watershed, and the soil- conservation projects should be built according to the eontribution rate of the erosion factors.

关键词： Chinese Soil Loss Equation (CSLE) Erosion risk Geographically weighted regression(GWR) Yellow River

Co_(3)O_(4)as an efficient passive NO_(x) adsorber for emission control during cold-start of diesel engines

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Chinese Journal of Chemical engineering 2024年第2期66卷 1-7页

作者： Jinhuang Cai Shijie Hao Yun Zhang Xiaomin Wu Zhenguo Li Huawang Zhao Department of environmental Science&engineering College of Chemical EngineeringHuaqiao UniversityXiamen 361021China Wuxi Weifu environmental Catalysts Co. LtdWuxi 214000China National engineering Laboratory for Mobile Source Emission Control Technology China Automotive Technology&Research Center Co.Ltd.Tianjin 300300China

The Co_(3)O_(4)nanoparticles,dominated by a catalytically active(110)lattice plane,were synthesized as a low-temperature NO_(x) adsorbent to control the cold start emissions from *** nanoparticles boast a substantial quantity of active chemisorbed oxygen and lattice oxygen,which exhibited a NO_(x) uptake capacity commensurate with Pd/SSZ-13 at 100℃.The primary NO_(x) release temperature falls within a temperature range of 200-350℃,making it perfectly suitable for diesel *** characterization results demonstrate that chemisorbed oxygen facilitate nitro/nitrites intermediates formation,contributing to the NO_(x) storage at 100℃,while the nitrites begin to decompose within the 150-200℃***,lattice oxygen likely becomes involved in the activation of nitrites into more stable nitrate within this particular temperature *** concurrent processes of nitrites decomposition and its conversion to nitrates results in a minimal NO_(x) release between the temperatures of 150-200℃.The nitrate formed via lattice oxygen mainly induces the NO_(x) to be released as NO_(2) within a temperature range of 200-350℃,which is advantageous in enhancing the NO_(x) activity of downstream NH_(3)-SCR catalysts,by boosting the fast SCR reaction *** to its low cost,considerable NO_(x) absorption capacity,and optimal release temperature,Co_(3)O_(4)demonstrates potential as an effective material for passive NO_(x) adsorber applications.

关键词： Emission control cold-start Low-temperature adsorption Co_(3)O_(4) Nitrate formation

Estimation of the quantity of aeolian saltation sediments blown into the Yellow River from the Ulanbuh Desert,China

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Journal of arid Land 2014年第2期6卷 205-218页

作者： HeQiang DU Xian XUE Tao WANG cold and arid regions environmental and engineering research Institute Chinese Academy of Sciences

The Ulanbuh Desert borders the upper reach of the Yellow River. Every year, a mass of aeolian sand is blown into the Yellow River by the prevailing wind and the coarse aeolian sand results in serious silting in the Yellow River. To estimate the quantity of aeolian sediments from the Ulanbuh Desert blown into the Yellow River, we simulated the saltation processes of aeolian sediments in the Ulanbuh Desert. Then we used a saltation submodel of the IWEMS （integrated Wind-Erosion Modeling System） and its accompanying RS （Remote Sensing） and GIS （Geographic Information System） modules to estimate the quantity of saltation sediments blown into the Yellow River from the Ulanbuh Desert. We calibrated the saltation submodel by the synchronous observation to wind ve- locity and saltation sediments on several points with different vegetation cover. The vegetation cover, frontal area of vegetation, roughness length, and threshold friction velocity in various regions of the Ulanbuh Desert were obtained using NDVI （Normalized Difference Vegetation Index） data, measured sand-particle sizes, and empirical relation- ships among vegetation cover, sand-particle diameters, and wind velocity. Using these variables along with the observed wind velocities and saltation sediments for the observed points, the saltation model was validated. The model results were shown to be satisfactory （RMSE less than 0.05 and IRel less than 17%）. In this study, a subdaily wind-velocity program, WlNDGEN, was developed using this model to simulate hourly wind velocities around the Ulanbuh Desert. By incorporating simulated hourly wind-velocity and wind-direction data, the quantity of saltation sediments blown into the Yellow River was calculated with the saltation submodel. The annual quantity of aeolian sediments blown into the Yellow River from the Ulanbuh Desert was 5.56x106 t from 2001 to 2010, most of which occurred in spring （from March to May）; for example, 6.54x10~ tons of aeolian sand were blown in

关键词： aeolian sand sediments integrated wind-erosion modeling system NDVI WlNDGEN Ulanbuh Desert

Glacier area change and its impact on runoff in the Manas River Basin,Northwest China from 2000 to 2020

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Journal of arid Land 2024年第7期16卷 877-894页

作者： WANG Tongxia CHEN Fulong LONG Aihua ZHANG Zhengyong HE Chaofei LYU Tingbo LIU Bo HUANG Yanhao College of Water Conservancy&Architectural engineering Shihezi UniversityShihezi 832000China Key Laboratory of cold and arid regions Eco-Hydraulic engineering of Xinjiang Production&Construction Corps Shihezi 832000China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing 100038China College of Sciences Shihezi UniversityShihezi 832000China

Understanding the distribution and dynamics of glaciers is of great significance to the management and allocation of regional water resources and socio-economic development in arid regions of Northwest *** this study,based on 36 Landsat images,we extracted the glacier boundaries in the Manas River Basin,Northwest China from 2000 to 2020 using eCognition combined with band operation,GIS(geographic information system)spatial overlay techniques,and manual visual *** further analyzed the distribution and variation characteristics of glacier area,and simulated glacial runoff using a distributed degree-day model to explore the regulation of runoff *** results showed that glacier area in the Manas River Basin as a whole showed a downward trend over the past 21 a,with a decrease of 10.86%and an average change rate of–0.54%/*** the increase in glacier scale,the number of smaller glaciers decreased exponentially,and the number and area of larger glaciers were relatively *** area showed a normal distribution trend of increasing first and then decreasing with *** 97.92%of glaciers were distributed at 3700–4800 m,and 48.11%of glaciers were observed on the northern and northeastern *** retreat rate of glaciers was the fastest(68.82%)at elevations below 3800 *** was a clear rise in elevation at the end of *** at different slope directions showed a rapid melting trend from the western slope to the southern slope then to the northern *** runoff in the basin showed a fluctuating upward trend in the past 21 a,with an increase rate of 0.03×10^(8) m^(3)/*** average annual glacial runoff was 4.80×10^(8) m^(3),of which 33.31%was distributed in the ablation season(June–September).The average annual contribution rate of glacial meltwater to river runoff was 35.40%,and glacial runoff accounted for 45.37%of the total runoff during the ablation *** addition,precipitation and glacial runoff had comp

关键词： glacier area glacial runoff climate change glacier boundary extraction distributed degree-day model Manas River Basin

Estimation of water balance in the source region of the Yellow River based on GRACE satellite data

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Journal of arid Land 2013年第3期5卷 384-395页

作者： Min XU BaiSheng YE QiuDong ZHAO ShiQing ZHANG Jiang WANG State Key Laboratory of Cryospheric Science Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences cold and arid regions environmental and engineering research Institute Chinese Academy of Sciences

Water storage has important significance for understanding water cycles of global and local domains and for monitoring climate and environmental changes. As a key variable in hydrology, water storage change represents the sum of precipitation, evaporation, surface runoff, soil water and groundwater exchanges. Water storage change data during the period of 2003-2008 for the source region of the Yellow River were collected from Gravity Recovery and Climate Experiment （GRACE） satellite data. The monthly actual evaporation was estimated according to the water balance equation. The simulated actual evaporation was significantly consistent and correlative with not only the observed pan （20 cm） data, but also the simulated results of the version 2 of Simple Biosphere model. The average annual evaporation of the Tangnaihai Basin was 506.4 mm, where evaporation in spring, summer, autumn and winter was 130.9 mm, 275.2 mm, 74.3 mm and 26.1 mm, and accounted for 25.8%, 54.3%, 14.7% and 5.2% of the average annual evaporation, respectively, The precipitation increased slightly and the actual evaporation showed an obvious decrease. The water storage change of the source region of the Yellow River displayed an increase of 0.51 mm per month from 2003 to 2008, which indicated that the storage capacity has significantly increased, probably caused by the degradation of permafrost and the increase of the thickness of active layers. The decline of actual evaporation and the increase of water storage capacity resulted in the increase of river runoff.

关键词： actual evaporation GRACE satellite data water storage change water balance equation source region of the Yellow River

Interaction between Adjacent Lightning Discharges in Clouds

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Advances in Atmospheric Sciences 2013年第4期30卷 1106-1116页

作者：王彦辉张广庶张彤李亚珺武斌张廷龙 Laboratory of Land Surface Process and Climate Change in cold and arid regions Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences

Using a 3D lightning radiation source locating system （LLS）, three pairs of associated lightning discharges （two or more adjacent lightning discharges following an arbitrary rule that their space-gap was less than 10 km and their time-gap was less than 800 ms） were observed, and the interaction between associated lightning discharges was analyzed. All these three pairs of associated lightning discharges were found to involve three or more charge regions （the ground was considered as a special charge region）. Moreover, at least one charge region involved two lightning discharges per pair of associated lightning discharges. Identified fl＇om electric field changes, the subsequent lightning discharges were suppressed by the prior lightning discharges. However, it is possible that the prior lightning discharge provided a remaining discharge channel to facilitate the subsequent lightning discharge. The third case provided evidence of this possibility. Together, the results suggested that, if the charges in the main negative charge region can be consumed using artificial lightning above the main negative charge regions, lightning accidents on the ground could be greatly reduced, on the condition that the height of the main negative charge region and the charge intensity of the lower positive charge region are suitable.

关键词： associated lightning inverted-polarity intracloud discharge charge region electrical structure

Response of Atmospheric Energy to Historical Climate Change in CMIP5

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Journal of Meteorological research 2015年第1期29卷 93-105页

作者：韩博吕世华高艳红奥银换李瑞青 Key Laboratory of Land Surface Process and Climate Change in cold and arid regions Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences

Three forms of atmospheric energy, i.e., internal, potential, and latent, are analyzed based on the historical simulations of 32 Coupled Model Intercomparison Project Phase 5（CMIP5） models and two reanalysis datasets（NCEP/NCAR and ERA-40）. The spatial pattern of climatological mean atmospheric energy is well reproduced by all CMIP5 models. The variation of globally averaged atmospheric energy is similar to that of surface air temperature（SAT） for most models. The atmospheric energy from both simulation and reanalysis decreases following the volcanic eruption in low-latitude zones. Generally, the climatological mean of simulated atmospheric energy from most models is close to that obtained from NCEP/NCAR, while the simulated atmospheric energy trend is close to that obtained from ERA-40. Under a certain variation of SAT, the simulated global latent energy has the largest increase ratio, and the increase ratio of potential energy is the smallest.

关键词： atmospheric energy CMIP5 historical climate change

Connection Between Atmospheric Latent Energy and Energy Fluxes Simulated by Nine CMIP5 Models

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Journal of Meteorological research 2015年第3期29卷 412-431页

作者：韩博吕世华李瑞青奥银焕陈昊高艳红马迪 Key Laboratory of Land Surface Process and Climate Change in cold and arid regions Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences

The atmospheric latent energy and incoming energy fluxes of the atmosphere are analyzed here based on the historical simulations of nine coupled models from the Coupled Model Intercomparison Project Phase 5 （CMIP5） and two reanalysis datasets. The globally averaged atmospheric latent energy is found to be highly correlated with several types of energy flux, particularly the surface latent heat flux, atmosphere absorbed solar radiation flux, and surface net radiation flux. On the basis of these connections, a hydrological cycle controlled feedback （HCCF） is hypothesized. Through this feedback, the atmosphere absorbed solar radiation is enhanced and causes intensification of the surface latent heat flux when the atmospheric latent energy is abnormally strong. The representativeness of the HCCF during different periods and over different latitudinal zones is also discussed. Although such a feedback cannot be confirmed by reanalysis, it proves to be a common mechanism for all the models studied.

关键词： atmospheric latent energy CMIP5 hydrological cycle climate feedback

Effect of traffic restriction on atmospheric particle concentrations and their size distributions in urban Lanzhou, Northwestern China

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Journal of environmental Sciences 2014年第2期26卷 362-370页

作者： Suping Zhao Ye Yu Na Liu Jianjun He Jinbei Chen Key Laboratory of Land Surface Process and Climate Change in cold and arid regions Cold & Arid Regions Environmental & Engineering Research Institute Chinese Academy of Sciences University of Chinese Academy of Sciences

During the 2012 Lanzhou International Marathon, the local government made a significant effort to improve traffic conditions and air quality by implementing traffic restriction measures. To evaluate the direct effect of these measures on urban air quality, especially particle concentrations and their size distributions, atmospheric particle size distributions （0.5-20μm） obtained using an aerodynamic particle sizer （model 3321, TSI, USA） in June 2012 were analyzed. It was found that the particle number, surface area and volume concentrations for size range 0.5-10 μm were （15.0±2.1） cm-3, （11.8±2.6） μm2/cm3 and （1.9±0.6） μm2/cm3, respectively, on the traffic-restricted day （Sunday）, which is 63.2%, 53.0% and 47.2% lower than those on a normal Sunday. For number and surface area concentrations, the most affected size range was 0.5-0.7 and 0.5-0.8 μm, respectively, while for volume concentration, the most affected size ranges were 0.5-0.8, 1.7-2.0 and 5.0-5.4 μm. Number and volume concentrations of particles in size range 0.5-1.0μm correlated well with the number of non-CNG （Compressed Natural Gas） powered vehicles, while their correlation with the number of CNG-powered vehicles was very low, suggesting that reasonable urban traffic controls along with vehicle technology improvements could play an important role in improving urban air quality.

关键词： traffic restriction particle concentration size distribution urban air quality