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Detection of Acid Rain Stress Effect on Plant Using Hyperspectral Data in three gorges region,China

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Chinese Geographical Science 2008年第3期18卷 249-254页

作者： SONG Xiaodong JIANG Hong YU Shuquan ZHOU Guomo International Institute for Earth System Science Nanjing University Nanjing 210093 China Institute of Urban Environment Chinese Academy of Sciences Xiamen 361003 China International Research Center of Spatial Ecology and Ecosystem Ecology Zhejiang Forestry University Hangzhou 311300 China

This paper aims to use hyperspectral data to detect the spectral change caused by acid stress to a native forest type in the three gorges region of China. For this purpose, a ground-based hyperspectral experiment was conducted at the three gorges region to detect acid deposition that caused Masson pine (Pinus massoniana) forest degra-dation. Continuum removal method was used to isolate wavebands more responsive to stress in wavelengths 450-750nm. The differences in chlorophyll concentrations and needle thickness caused by acidic stress are found to be explicable to the different spectral reflectance patterns in the visible and near-infrared wavelengths. Two new chlorotic indices were utilized to explain the stress-caused leaf chlorosis. The comparison of simulated vegetation indices and principal component analysis (PCA) results suggests that it would be possible to monitor acid rain stress effect on forest ecosystem from some wider spectral regions.

关键词： acid deposition reflectance continuum removal three gorges region

State of the climate in the three gorges region of the Yangtze River basin in 2020

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Atmospheric and Oceanic Science Letters 2022年第2期15卷 7-12页

作者： Tong Cui Xianyan Chen Xukai Zou Qiang Zhang Shuai Li Hongling Zeng National Climate Center China Meteorological AdministrationBeijingChina Operation and Administration Center for River Basin Hydro Complex China Three Gorges CorporationYichangChina

In 2020,the average air temperature in the three gorges region(TGR)of the Yangtze River basin was 17.2℃,which was close to normal,there were exceptionally fewer days than normal with high temperatures,and the high-temperature events mainly occurred in ***,the average precipitation was 1530.8 mm,which was a remarkable 29%more than usual,and the second-highest since *** precipitation was obviously above-normal in summer,and the precipitation in both June and July was the second-highest of the same period in *** average number of rainstorm days was higher than normal,and the second-highest since *** average wind speed in the TGR was apparently higher than normal;the average relative humidity was slightly higher than normal;and there were no instances of acid rain,with the rain acidity showing a significant weakening trend over the previous 15 *** the summer of 2020,the TGR experienced heavy rainstorms and flood *** shows that the frequent southward movement of cold air and abundant warm water vapor from the southwest were the direct causes of the abnormally high precipitation in the TGR from June to *** the spring of 2020,the continuously high sea surface temperature in the Indian Ocean led to a continuously strong western Pacific subtropical high and its average location being situated more to the south than normal,which might have been an important cause for the abnormal climate conditions in the Yangtze River basin from June to July.

关键词： three gorges region Yangtze River Climate state Weather and climate events Meteorological disasters

Climate state of the three gorges region in the Yangtze River basin in 2022–2023

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Atmospheric and Oceanic Science Letters 2024年第5期17卷 61-66页

作者： Tong Cui Xianyan Chen Xukai Zou Linhai Sun Qiang Zhang Hongling Zeng National Climate Center China Meteorological AdministrationBeijingChina

Based on daily observation data of the three gorges region(TGR)of the Yangtze River basin and global reanalysis data,the climate characteristics,climate events,and meteorological disasters of the TGR in 2022 and 2023 were *** the TGR,the average annual temperature for 2022 and 2023 was 0.8℃ and 0.4℃ higher than normal,respectively,making them the two warmest years in the past *** 2022,the TGR experienced its warmest summer on *** average air temperature was 2.4℃ higher than the average,and there were 24.8 days of above-average high temperature days during *** in the TGR varied significantly between 2022 and *** rainfall was 18.4%below normal and drier than normal in most parts of the *** contrast,the precipitation in 2023 was considerably higher than the long-term average,and above normal for almost the entire *** average wind speed exhibited minimal variation between the two ***,the number of foggy days and relative humidity increased in 2023 compared to *** 2022–2023,the TGR mainly experienced meteorological disasters such as extreme high temperatures,regional heavy rain and flooding,overcast rain,and inverted spring *** indicates that the abnormal western Pacific subtropical high and the abnormal persistence of the eastward-shifted South Asian high were the two important drivers of the durative enhancement of record-breaking high temperature in the summer of 2022.

关键词： three gorges region Climate state Extreme high temperature Torrential summer rainfall Climate analysis

Analysis of climatic features and major meteorological disasters over the three gorges region of the Yangtze River Basin in 2021

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Atmospheric and Oceanic Science Letters 2022年第6期15卷 57-63页

作者： Tong Cui Xianyan Chen Xukai Zou Qiang Zhang Hongling Zeng Linhai Sun National Climate Center China Meteorological AdministrationBeijingChina

Based on daily observation data in the three gorges region(TGR)of the Yangtze River Basin and global reanalysis data,the authors analyzed the climate characteristics and associated temporal variations in the main meteorological factors in 2021,as well as the year’s climatic events and meteorological *** 2021 average temperature was 0.2℃above the 1991-2020 average and the 13 th-warmest year since ***,winter and autumn were both warmer than *** annual mean precipitation was 12.8%above normal,and most regions experienced abundant rainfall throughout the *** seasonal variation in precipitation was significant and the TGR had a wetter-than-normal spring and *** number of rainstorm days was higher than normal;the wind speed was above normal;and the relative humidity was higher than *** terms of rain acidity,2021 was tied with 2020 as the lowest since *** mid-September to early October 2021,the TGR experienced exceptional high-temperature weather,which was driven by abnormal activity of mid-and high-latitude atmospheric circulation over the Eurasian continent and the western Pacific subtropical high(WPSH).In addition,a strong blocking high over the Ural Mountains accompanied by intense mid-latitude westerly winds prevented cyclonic disturbances from extending to the subtropical *** a result,under the combined effect of the weaker-than-normal cold-air activities and the anomalous WPSH,the TGR experienced extreme high-temperature weather during early autumn 2021.

关键词： three gorges region Climatic anomaly Weather and climate events Extremely warm early autumn

Climate observation of the three gorges region of the Yangtze River in 2019

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Atmospheric and Oceanic Science Letters 2021年第3期14卷 7-11页

作者： Xianyan Chen Xukai Zou Qiang Zhang Hongling Zeng Tong Cui National Climate Center China Meteorological AdministrationBeijingChina

This report provides a broad overview of the climate and the major weather and climate events over the three gorges region of the Yangtze River(TGR)in *** year 2019,a 0.3℃ warmer year than normal,had a colder winter and warmer spring,summer,and *** precipitation in 2019 was 13%less than *** average normal rainfall amounts were received in all four seasons,with 28%and 16%less-than-normal in winter and summer,*** annual mean wind speed in the TGR was higher than normal,and relative humidity was near normal for all four *** intensity of acid rain in 2019 was the weakest since *** major climate events and meteorological disasters in the TGR in 2019 included heat waves,drought,and *** waves occurred frequently and persisted for long *** and autumn drought occurred in central and eastern regions of the *** autumn rains of West China occurred earlier this year,which brought much more rainfall than normal in central and western regions of the TGR.

关键词： three gorges region Yangtze River Climate summary Weather and climate events

Micromorphology of landslide soil Case study on the Jibazi landslide in Yunyang in the three gorges region, China

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Journal of Mountain Science 2006年第2期3卷 147-157页

作者： HE Yurong CUI Peng LIAO Chaolin ZHANG Baohua ZHAO Yu Chengdu Institute of Mountain Hazards and Environment Chinese Academy of Science ＆ Ministry of Water Conservation Chengdu 610064 China

Abstract： Landslide is one of natural catastrophes affecting national economy and people＇s livelihood. There are many reports on the forming mechanism and control of landslide, but the studies on micromorphology of landslide soil are few. There are many potential landslides in the three gorges region in China. In this paper, the micromorphologic features of the Jibazi landslide soil in Yunyang in the three gorges region of the Yangtze River were studied using routine methods, that is, soil micromorphology, X-ray diffraetometer and scanning electron microscope. The main conclusions are as follow：（1） The basic micromorphologic characteristics of the landslide soil are that the fine soil particles are commonly cohesive matrix, finer and lower content of skeleton grains, the microstructures are mainly types of phenocrystal gelatinization, densely chap and fissure structure. As a result, these micromorphologic features affect the discharging of soil water, favor the movement of landslide body and provide an internal basis of materials for the formation of landslide. （2） The concept on the forming material of landslide was proposed, and types of optical beamed clay aggregates, Fe-Mn isolates and glassy material were found in landslide-belt soil, which were remarkably different from the natural soil formation, and had some scientific significance in analyzing the forming mechanism of landslide and distinguishing me landslide-belt soil. （3） Some special micromorphologic and sub-micromorphologic characteristics, such as fingerprint microstructure, clay beamed bedding microstructure, oppressive microstructure, moulage microstructure and extending hole microstncture, could bring useful micromorphologic evidences for the observation and forecasting of landslide. The results mentioned above will bring helpful micromorphologic evidences for distinguishing slide soil, analyzing the formation mechanism of landslide, and monitoring and forecasting the occurrence of landslide.

关键词： Landslide Microstructure forming material of landslide three gorges region China

Temporal stability analysis of soil moisture along a coniferous forest hillslope with subtropical monsoon climate in southwest China

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Journal of Mountain Science 2021年第11期18卷 2900-2914页

作者： BAI Yu-shi LIU Mu-xing YI Jun ZHANG Hai-lin Hubei Province Laboratory for Geographical Process Analyzing&Modeling Wuhan 430079China College of Urban and Environmental Sciences Central China Normal UniversityWuhan 430079China Research Institute of Sustainable Development Central China Normal UniversityWuhan 430079China

Soil water content(SWC)plays a crucial role in simulating hydrological process,guiding reforestation and controlling soil erosion in mountainous ***-temporal variability of SWC increases the difficulty of quantifying SWC pattern in the prediction of soil *** stability analysis of SWC can reduce the labor consuming and simplify the costly field *** study aimed to evaluate the temporal stability of SWC at hourly,daily and monthly temporal periods and its controlling factors at a hillslope in the three gorges *** SWC of five soil depths was monitored at 5 topographic locations(toe,lower,middle,upper and top slope positions)along a 170 m hillslope in the three gorges region(110°04'~112°04'E,29°53'~31°34'N),Yichang City,Hubei Province,China from May 4^(th),2018 to May 3^(rd),*** results showed thatthe coefficient of variation of SWC ranged from 4%to 49%,which increased with rising soil depth within 40 cm but thereafter ***,the high Spearman's rank coefficients(Pthree temporal *** locations(RLs)varied in the different soil depths,which weretoe,upper and middle slope positions at 0~40,40~60 and 60~80 cm depthsof the investigated hillslope,*** hydraulic conductivity served as adominant factor controlling the temporal stability of *** result advances our thorough understanding of hydrology and soil water resource in the three gorges region.

关键词： Soil water content Temporal stability Representative location Hillslope hydrology Temporal period three gorges region

The　fine　velocity　structure　of　sediment－base－ment　layer　in　the　three－gorgesregionoftheChangjiangRiver（YangtzeRiver）

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Acta Seismologica Sinica(English Edition) 1996年第3期9卷 52-59页

作者：胡鸿翔边银菊高世玉

In this paper, the study on the fine velocity structure of sedimental and basement layers along 4 deep seismic sounding profiles in the three gorges region of the Changjiang River (Yangtze River) are presented. The velocity of sedimental cover is larger in hills of western Hubei in the western profiles, the total thickness is about 0～0.3 km. However, it becomes thick in southern part of Zigui basin and Zushui river valley, about 5.0 km and 4.0 km thick respectively. The sedimental cover is very thick in Jianghan plains in the eastern profiles, about 5～8 km, and the velocity is lower. The velocity of basemental plane is greater than 6.0 km/s over the whole region. An interface can be divided within the sedimental layer, it is about 3～4 km deep in Jianghan plains, while it approximates to surface in other regions. The profiles are cut by faults in many positions. Where the faults pass, the velocity isopleth varies sharply, and the velocity is obviously low. The basement layer is characterized by high velocity and low gradient, there exist 3 high velocity anomalous zones within the layer, which are located at the west, south and east of Huangling Anticlinorium respectively. They are the upwelling materials of basalt magma with high velocity from deep crust. Perhaps, this process took place before formation of Huangling Anticlinorium. Its action produces the significant variation of basement plane depth and the correspondent development and action of faults.

关键词： three gorges region sedimental layer basement layer velocity structure high velocity anomalous zone fault.