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Li L.-G.,Institute of Atmospheric Environment | Liu X.-M.,Shenyang Regional Climate Center | Zhao X.-L.,Institute of Atmospheric Environment | Wang H.-B.,Institute of Atmospheric Environment | And 2 more authors.
Chinese Journal of Applied Ecology | Year: 2010

The monthly, annual, and inter-decade variations of heat island effect in inner and outer suburbs of Shenyang and their relationships with urbanization were analyzed, based on the air temperature data from 1961 to 2008. It was indicated that the monthly and annual heat island effect was higher in inner suburb than in outer suburb, and decreased from inner suburb to outer suburb. The variation trend of monthly heat island effect in inner and outer suburbs was similar from March to November, but in contrary from December to next February, possibly due to the effects of heating in winter. The annual heat island effect in both inner and outer suburbs had an increasing trend before 2000 but a decreasing trend after 2000, and was significantly positively correlated with the green land area, population, and established construction area before 2000 (P<0. 05), but significantly negatively correlated with them after 2000 (P<0. 05), the correlation degree being 0. 43, 0. 52, and 0. 26, respectively.

Zhang X.,Chinese Academy of Meteorological Sciences | Zhou X.,Shenyang Regional Climate Center | Zhang H.,Chinese Academy of Meteorological Sciences
Huanjing Kexue Xuebao/Acta Scientiae Circumstantiae | Year: 2015

Based on the surface observation data, this study established the time series of aerosol optical depth (AOD) of Huangshi city in Hubei Province in recent 60 years by using climate trend analysis and correlation analysis. The relationship between AOD and precipitation was investigated. The results showed that AOD increased significantly in Huangshi city in recent 60 years, with the maximum in 1991. The numbers of precipitation days and light rain days showed obvious decrease, while the numbers of moderate and heavy rain days increased and the change of rainstorm days was not significant. Light rain precipitation decreased with the significant increase of AOD, while the change trend of moderate precipitation and above was not obvious. In summary, the increase of AOD in Huangshi city in recent 60 years had impact on number of rainy days and precipitation, while the correlation remained to be further studied. ©, 2015, Science Press. All right reserved.

Lin Y.,Liaoning Province Public Meteoro logical Service Center | Li Q.,Shenyang Regional Climate Center | Wang H.-B.,Institute of Atmospheric Environment | Ji R.-P.,Institute of Atmospheric Environment | And 6 more authors.
Chinese Journal of Ecology | Year: 2016

Using the data observed with ASD FieldSpec Pro FR spectroradiometer based on a trial with various levels of drought stress during different growth periods of maize in Jinzhou, Liaoning Province, the variation characteristics of maize canopy hyperspectral reflectance were investigated and inversion models on soil water content considering spectral parameters were established. The results showed that, after drought stress during the period from seven leaves to jointing, the spectral reflectance within spectral bands of 750 to 1400 nm, the amplitude and the area of red edge decreased and the time of their response to drought stress was shorter, and differed from those un-der well-watered condition, while the reflectance within the spectral bands from 350 to 750 nm and from 1400 to 2300 nm demonstrated an increasing trend. As far as inversion methods, the inversion error of soil water content with regression method based on hyperspectral reflectance was smaller than that of first derivative spectra. Moreover, the inversion accuracy of soil water content at the 10 cm depth was higher than that at the depth of 30 cm. © 2016, editorial Board of Chinese Journal of Ecology. All Rights Reserved.

Liu N.,Institute of Atmospheric Environment | Ma Y.,Institute of Atmospheric Environment | Liu X.,Shenyang Regional Climate Center | Zhang Y.,Institute of Atmospheric Environment | And 2 more authors.
Huanjing Kexue Xuebao/Acta Scientiae Circumstantiae | Year: 2011

In order to study the temporal variation of haze and fog in Shenyang, haze and fog times were determined from the hourly visibility, particle concentration, relative humidity and weather patterns, observed for one whole year from 1 June 2009 to 31 May 2010. Based on the experimental criteria and definitions, the haze times account for 53.9% of the total observations; far higher than the fog proportion of 8.4%. Considering the temporal variation, haze occurs most frequently in winter and fog reaches a peak in summer. They both appear comparatively frequently in autumn, while rarely in spring. The seasonal variation of particles is the same as that of haze, which means that haze is closely associated with air pollution and visibility. Haze is definitely an indicator of the city air quality. Haze times from mild to severe grade account for 72.1%, 18.2%, 6.5% and 3.2% of the total observational times. The proportion of medium and severe grade haze times is rather low. It can be seen that human health has not been affected seriously in Shenyang, but everyone should take health precautions in autumn and winter.

Feng C.,Liaoning Academy of Agricultural science | Zheng J.-M.,Liaoning Academy of Agricultural science | Feng L.-S.,Liaoning Academy of Agricultural science | Yu X.-J.,Shenyang Regional Climate Center | And 3 more authors.
Applied Mechanics and Materials | Year: 2014

In this study, the soil column experiment was adopted to investigated the release characteristic of P from soil by citric acid leaching. The results showed that the P release characteristics were different from each other under various citrate concentrations. At high concentration (50 mM) treatment, P concentration of effluents increased rapidly with effluent volume at the beginning, reached the maximum value after approximately 150 ml solution had passed through the columns. For the column treated with 5 mM of citric acid, the P in leachates was increased gradually to the maximum concentration, and then approached a relatively stable level during the 1000-3050 ml effluent volume. For low concentration (0.5 mM) treatment, the level of P in the effluents has always been very low, though a small peak was observed during the leaching. ©(2014) Trans Tech Publications, Switzerland.

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