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Copyright of Arid Zone Research / Ganhanqu Yanjiu is the property of Arid Zone Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mountain Research (10082786) is the property of Mountain Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Wide longitudinal ridge tillage has significant effects for increasing crop yield. Field observation shows that in the black soil region of Northeast China, wide longitudinal ridge tillage has been widely promoted in the intensive farms on which large agricultural machines are used. However, hillslope soil erosion of wide longitudinal ridge tillage is seldom studied. Therefore, in typical black soil region, in this study, two large natural runoff plots with gentle slope gradient were established in Liangshigou watershed in Keshan County, Heilongjiang Province. One was wide longitudinal ridge tillage with 320 m slope length and 3-m slope width and another was narrow longitudinal ridge tillage with 320 m slope length and 2 m slope width. Ridges were established on a field of silty clay loam (USDA classification). The slope gradients ranged from 2°-7°. According to literature review and field measurements of the wide and narrow ridges in black soil region of Northeast China, the used wide ridges were 15-cm high, 110-cm wide; the used narrow ridges were 15- cm high, 65 cm wide. A laboratory simulated rainfall experiment was conducted in the simulated rainfall hall of the State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Yangling City, China. The soil used in the laboratory simulated rainfall experiment was collected in the natural runoff plot. According to the standard of erosive rainfall in Northeast black soil region of China, the simulated rainfall intensities were 50, 75 and 100 mm/h. Each rainfall experiment lasted 60 min. The wide and narrow ridges used in the simulated experiments were consistent with the large natural runoff plot in Keshan County. Based on the runoff plot observation and laboratory simulated rainfall experiments, the differences of hillslope soil erosion between wide and narrow longitudinal ridge tillage in black soil region of China were analyzed. The results showed that under both field runoff observation and laboratory simulation, hillslope soil losses from the wide longitudinal ridge tillage hillslope were 64.4% - 90.4% and 33.2% - 57.9% lower than that from the narrow longitudinal ridge tillage. Field observation indicated that there were significant or strong significant positive correlations among the soil loss, runoff and PI30. The increment of soil loss with runoff and PI30 in narrow ridge-tillage system was larger (P< 0.05) than that in wide ridge-tillage system. The relationship between soil loss and PI30 was power function, while the relationship between soil loss and runoff was linear function (R²＞0.99). Indoor simulated experiments showed that there were linear relationships between soil loss and runoff under two longitudinal ridge tillage systems (R²≥0.81). The increment of soil loss from the wide longitudinal ridge tillage system was lower (P< 0.05) than that from the narrow longitudinal ridge tillage system. Compared with the narrow longitudinal ridge tillage, the reduction of soil loss by wide longitudinal ridge tillage decreased with the increase of PI30; when PI30 was 433.9 - 605.1, the reduction of soil loss by the wide longitudinal ridge tillage was 74.8%-90.4% and when PI30 were 1520.6 and 1708.6, the reduction of soil loss by the wide longitudinal ridge tillage was 64.4%-66.5%. Both field observation and simulated experiments displayed that the wide longitudinal ridge tillage had better effects on controlling hillslope soil erosion, compared with the traditional narrow ridge tillage. Therefore, promotion of wide ridge tillage system might have great significance in protecting Mollisol resources in the black soil region of Northeast China. [ABSTRACT FROM AUTHOR]

A modified typhoon numerical model is proposed based on data measured during the landfall of several typhoons as well as the fitting relationships of typical typhoon field parameters such as the maximum wind speed radius Rmali associated with storm scale field and radial pressure distribution coefficient βrelated to pressure field. The modified model considers the correlation among field parameters and is applicable for the region of Southeast coast of China. Using the field observation data of 57 typhoons from 1971 to 2015 in the Houjia Town meteorological station, Shanghai, the equivalent roughness length of engineering site was optimized as z0 = 0. 095 m. The validation of maximal wind speeds for each typhoon between the observed and simulated results was conducted. Combining the observation data of typhoon tracks and the fitting relationships of typical field parameters，the wind speeds observed by Houjia Town station of four typically stronger typhoons was reproduced by the improved typhoon engineering model. The relative errors of maximum wind speeds between the observations and the model are within 12%. It is demonstrated that the present model is sufficiently reliable for predicting the maximum typhoon winds. Basic wind speeds and profiles of the Houjia Town station and typical engineering sites in the Shanghai region were calculated via the Monte-Carlo stochastic simulation method and the peak over Threshold method. The 10 min mean wind speed at a height of 10 m with the return period of 100 years in the Houjia Town station and the category B exposure (20 = 0.05m) of Shanghai are 31. 51 m/s and 37. 46 m/s with the standard derivation of 2. 05 m/s and 2. 66 m/s, respectively. Moreover, the preferable mean wind profile models for engineering sites with four kinds of category under typhoon winds were suggested after comparing three different wind profile models. [ABSTRACT FROM AUTHOR]

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The field observation and research station (network) provides a field test and research platform for the development of practical disciplines such as geography and ecology, which is one of the important contents of the "Double first-class" discipline construction of Lanzhou University. Under the background of the "Double first-class" construction, this paper discusses the objectives, orientation, construction mode and operation mechanism of the construction of the field observation and research station (network) of Lanzhou University in Qilian Mountain area, aiming to make the monitoring network better serve the ecological protection and comprehensive management of Qilian Mountain area, and to support the construction of the "Double first-class" discipline construction in Lanzhou University. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to study the influence law of overlying roadway caused by lower protective seam mining, take the Liuxibeier Roadway of No. 3 coal seam of Guozhuang Mine as research object, the deformation of surrounding rock was measured. The results showed that the Liuxibeier Roadway was influenced by the No. 9 coal seam extraction under the specified condition of lower protective seam mining. According to the degree of roadway affected, roadway could be divided into three area during the mining period: initial influence area, intense influence area, post-mining influence area. The real deformation law of the roadway was in general accord with the deep deformation law of the roadway. The largest deformation rate area was located in the range of 13-20 m from the mining face. The damage depth of the roadway floor was about 7-8 m, and the degree of damage was worse with the shallow depth, the whole settlement amount of overlying coal roadway was comparatively large, and the accumulative covergence was about 1. 1-1.4 m. The results would provide scientific basis for support and reinforcement of overlying coal roadway under the similar condition. [ABSTRACT FROM AUTHOR]

To investigate the influence of Songhua River on Harbin and its surrounding areas during summer and winter and present a theoretical support for correct utilization and optimization of the urban river, a ground data collecting approach combined with remote sensing data collecting is used to analyze the remote sensing images of January 25 and June 1 in 2004. This method based on the reach of Songhua River confirms the impact of Songhua River Basin on its adjacent areas according to the distributions of temperature and moisture in summer and winter. The results reveal that in summer the temperature inside the city is abnormally higher than that in the suburb area and there is a tendency of surface temperature increase from water area to both banks, moreover, that in the northern side is more manifest than that in the southern facet. While the suburb humidity value is comparatively low and the distribution of relative humidity is centered as the Songhua River and its adjacent areas, meanwhile, the influenced radius of northern bank is larger. In winter, the temperature inside the city is approximately 4 °C higher than that in the suburb area and the distribution of temperature along either side of Songhua River differs a lot. The surface temperature of the frozen river resembles that of southern bank, while it is 2 °C higher than that of northern bank. With urban humidity about 1% lower than that in the suburb, it is reasonable that the distribution of humidity of Harbin accords with the dry island effect in winter. This study lays a data base and a technical support for the pointing observation and moving measurement in the future. [ABSTRACT FROM AUTHOR]

Liquid water (cloud/fog droplets and aerosols) is ubiquitous in the atmosphere and can provide an important reaction media for aqueous-phase chemical reactions. Gaseous precursors (mainly VOCs) or their gas-phase initial or first-generation oxidation products (including intermediate-volatility and semi-volatile organic compounds; I/SVOCs) can undergo chemical reactions in the atmospheric condensed phase (aqueous phase) to form low-volatility, highly oxidized organic matter[e.g., some key tracer species such as organosulfates (OSs) and organonitrogens (ONs)]. These products largely remain in the particle phase upon water evaporation and are referred to as aqueous secondary organic aerosols (aqSOAs). aqSOAs have been emerging as a research hot topic in atmospheric chemistry, as they can contribute significantly to OAs and thus have important impacts on the environment, climate, and human health. Despite considerable progress, so far, aqSOAs remain poorly understood owing to their complex formation mechanisms. In this review, we focus mainly on the relevant research results on the SOAs formed in aerosol water-aqueous aerosol SOAs (aaSOAs)-including gas-phase precursors, formation mechanisms, laboratory simulations, and field observations, as well as SOA yield and contribution to OAs. Meanwhile, we propose future directions regarding studies of sources and formation mechanisms of aaSOAs, including identification of unknown aaSOA precursors and tracer products, photosensitizer-triggered radical chemistry, formation pathways of OS and ON compounds, field observations and model simulations of aaSOAs.