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Influence of climatic factors on tree-ring maximum latewood density of Picea schrenkiana in Xinjiang, China

Frontiers of Earth Science 2016年第1期10卷 126-134页

作者： Yu SUN Lili WANG Hong YIN Key Laboratory of Land Surface Pattem and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China National Climate Center China Meteorological Administration Beijing 100081 China

The influence of temperature and precipitation on maximum latewood density （MXD） was mainly discussed in this paper, based on the samples of Picea schrenkiana from the Manas River Basin, Xinjiang, China. The correlation analysis between MXD and instrumental records from the Shihezi Meteorological Station showed that the MXD was positively related to the mean maximum temperature throughout the growing season at high elevations. Comparatively, the ring-width at low altitudes was limited by the precipitation in May-June. The composite chronology by MXD sequences was highly correlated with the mean maximum temperature in July- August （r = 0.54,p 〈 0.001）, which was then reconstructed by the composite chronology. The comparative analysis on the reconstructed temperatures, observed values, and drought indices （Is） revealed that precipitation would affect MXD when the absolute value of Is was greater than 1.5a （i.e., ｜Is｜〉 2.5） in the period of 1953-2008 A.D. or close to 1.5σ for 2-3 consecutive years. The response characteristics are linked with the semiarid climate in the study area. In a single year or consecutive years of extreme dryness, the lack of precipitation would limit the thickening oflatewood cell walls and thus impact the MXD. All in all, if a MXD chronology is aimed to reconstruct temperature history, the moisture conditions at the sampling site should be considered prudently.

关键词： Picea schrenkiana tree-ring maximum late-wood density air temperature precipitation

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Vertical differentiation of land cover in the central Himalayas

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Journal of Geographical Sciences 2020年第6期30卷 969-987页

作者： ZHANG Yili WU Xue ZHENG Du Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Re-sources ResearchCASBeijing 100101China CAS Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Characterized by obvious altitudinal variation,habitat complexity,and diversity in land cover,the *** region within the central Himalayas is one of the most sensitive areas to climate change in the *** the same time,because the *** region possesses the most complete natural vertical spectrum in the world,it is also an ideal place to study the vertical structure of alpine land *** this study,land cover data for 2010 along with digital elevation model data were used to define three methods for dividing the northern and southern slopes in the *** region,i.e.,the ridgeline method,the sample transect method,and the sector *** altitudinal distributions of different land cover types were then investigated for both the northern and southern slopes of the *** region by using the above three division methods along with ArcGIS and MATLAB *** results indicate that the land cover in the study region was characterized by obviously vertical zonation with the south-six and north-four pattern of vertical spectrum that reflected both the natural vertical structure of vegetation and the effects of human *** low to high elevation,the main land cover types were forests,grasslands,sparse vegetation,bare land,and glacler/snow *** compositions and distributions of land cover types differed significantly between the northern and southern slopes;the southern slope exhibited more complex land cover distributions with wider elevation ranges than the northern *** area proportion of each land cover type also varied with ***,the vertical distribution patterns of different land cover types on the southern and northern slopes could be divided into four categories,with glaciers/snow cover,sparse vegetation,and grasslands conforming to unimodal *** distribution of bare land followed a unimodal pattern on the southern slope but a bimodal pattern on the northern ***,the use o

关键词： land cover altitudinal zonation central Himalayas Mt.Qomolangma Mt.Makalu Mt.Cho Oyu

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Climate extremes revealed by Chinese historical documents over the middle and lower reaches of the Yangtze River in winter 1620

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Advances in Climate Change Research 2014年第3期5卷 118-122页

作者： YAN Jun-Hui LIU Hao-Long HAO Zhi-Xin ZHANG Xue-Zhen ZHENG Jing-Yun Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences College of Urban and Environmental Sciences Xinyang Normal University

The snow-cover days over the middle and lower reaches of the Yangtze River(MLRYR) were extracted from Chinese historical documents for the winter of 1620, which includes the beginning of the tenth month of 1620 through the middle ten days of the second month of 1621 in Chinese lunar calendar. By using these records, the winter temperature anomalies compared with the 1961e1990 mean at nine stations were estimated. The results show an average of 50 snow-cover days over the MLRYR ranging from 30 d in Shanghai to 100 d in Jingzhou. The average snow-cover duration was approximately 70 d in Hefei, Huoshan, Nanjing, and Chaohu, and 40e60 d in Anqing, Wuhan, Changde,Changsha, and Jingdezhen. However, Shanghai and southern Jiangsu province had the lowest number of snow-cover days at 30 d. The regional mean winter temperature in 1620 was estimated to be 4.4C lower than the 1961e1990 mean. The maximum negative anomaly of 5.7C occurred in Jingdezhen, and the minimum anomaly of 3.6C was detected in Changsha. Both anomalies were significantly lower than those of the coldest winter during the instrumental observation period.

关键词： Climate extremes Snow-cover days Chinese historical documents Middle and lower reaches of the Yangtze River Winter of 1620

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Conversion of carbonaceous materials into solid acids for tylosin mitigation:effect of preprocessing methods on the reactivity of sulfonation reaction

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Biochar 2023年第1期5卷 558-573页

作者： Chunmei Wang Qianqian Xie Xiaomin Dou Lanxi Zhang Xiao Yang College of Environmental Science and Engineering Beijing Forestry UniversityBeijing 100083People’s Republic of China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101People’s Republic of China

Carbon-based solid acids have been successfully employed as acidic catalysts for pollutant mitigation in *** fully tap the potentials of commercially viable carbons for the preparation of solid acids and enhance their catalytic performances is a challenging *** this work,three commercialized carbons including biochar,activated carbon and graphite were preprocessed(ball-milling,Hummer exfoliation,HNO3 soaking,and microwave heating in HNO_(3),etc.),sulfonated,and evaluated as solid-acid catalysts for tylosin ***-originated solid acid performed the best through a balling-milling preprocess,while biochar-originated solid acids behaved well under all preprocessing treatments,in which 40 mg L^(−1) of tylosin was mitigated within 8 min by 1 g L^(−1) of biochar-originated solid *** biochar solid acid through the ball-milling preprocess presented high total acidity and large amounts of-SO_(3)H groups,due to dramatically increased surface area and the rise of activation groups(hydroxyl,alkyl and alkoxy groups,etc.)facilitating electrophilic *** addition,decreased particle size and aromaticity and increased structural defects also *** calculation of average local ionization energy(ALIE)of condensed aromatic model molecules with substituted activation groups confirmed the promoting effects on sulfonation from strong to weak were 8.40-9.06 *** findings have deepened the knowledge in tuning carbon surface chemistry for better sulfonation,thus strengthening catalytic degradation of *** value of this study is in pulling a clear thread for maneuvering solid-acid catalysts using carbons,which holds a novel promise for rationally functionalizing biochar-based catalysts for the remediation of macrolide antibiotics in polluted water.

关键词： Biochar engineering Sulfonation Heterogeneous catalysis Tylosin hydrolysis Antibiotic remediation

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Monthly variations of groundwater arsenic risk under future climate scenarios in 2081–2100

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Environmental Science and Pollution Research 2023年第58期30卷 122230-122244页

作者： Wei, Binggan Yin, Shuhui Yu, Jiangping Yang, Linsheng Wen, Qiqian Wang, Ting Yuan, Xing Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 11 A Datun Road Beijing100101 China College of Resources and Environment University of Chinese Academy of Sciences Beijing100049 China

The seasonal variations of shallow groundwater arsenic have been widely documented. To gain insight into the monthly variations and mechanisms behind high groundwater arsenic and arsenic exposure risk in different climate scenarios, the monthly probability of high groundwater arsenic in Hetao Basin was simulated through random forest model. The model was based on arsenic concentrations obtained from 566 groundwater sample sites, and the variables considered included soil properties, climate, topography, and landform parameters. The results revealed that spatial patterns of high groundwater arsenic showed some fluctuations among months under different future climate scenarios. The probability of high total arsenic and trivalent arsenic was found to be elevated at the start of the rainy season, only to rapidly decrease with increasing precipitation and temperature. The probability then increased again after the rainy season. The areas with an increased probability of high total arsenic and trivalent arsenic and arsenic exposure risk under SSP126 were typically found in the high-arsenic areas of 2019, while those with decreased probabilities were observed in low-arsenic areas. Under SSP585, which involves a significant increase in precipitation and temperature, the probability of high total arsenic and trivalent arsenic and arsenic exposure risk was widely reduced. However, the probability of high total arsenic and trivalent arsenic and arsenic exposure risk was mainly observed in low-arsenic areas from SSP126 to SSP585. In conclusion, the consumption of groundwater for human and livestock drinking remains a threat to human health due to high arsenic exposure under future climate scenarios. © 2023, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.

关键词： Groundwater

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Heterogeneity of water-retention capacity of forest and its influencing factors based on meta-analysis in the Beijing-Tianjin-Hebei region

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Journal of Geographical Sciences 2021年第1期31卷 69-90页

作者： SHI Xiaoli DU Chenliang GUO Xudong SHI Wenjiao Hebei Key Laboratory of Environmental Change and Ecological Construction College of Resources and Environmental SciencesHebei Normal UniversityShijiazhuang 050024China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China Hebei Technology Innovation Center for Remote Sensing Identification of Environmental Change Shijiazhuang 050024China Land Surveying and Planning Institute Key Laboratory of Land UseMinistry of Natural ResourcesBeijing 100035China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China

Water retention is important in forest ecosystem services. The heterogeneity analysis of water-retention capacity and its influencing factors is of great significance for the construction of water-retention functional areas, restoration of vegetation, and the protection of forest ecosystems in the Beijing-Tianjin-Hebei region. A total of 1366 records concerning water-retention capacity in the canopy layer, litter layer, and soil layer of forest ecosystem in this region were obtained from 193 literature published from 1980 to 2017. The influencing factors of water-retention capacity in each layer were analyzed, and path analysis was used to investigate the contribution of the factors to the water-retention capacity of the three layers. The results showed that mixed forests had the highest water-retention capacity, followed by broad-leaved forests, coniferous forests, and shrub forests. In addition, no matter the forest type, the ranking of the water-retention capacity was soil layer, canopy layer, and litter layer from high to low. The main influencing factors of water-retention capacity in forest canopy were leaf area index and maximum daily precipitation(R2=0.49), and the influencing coefficients were 0.34 and 0.30, respectively. The main influencing factors of water-retention capacity in the litter layer were semi-decomposed litter(R2=0.51), and the influencing coefficient was 0.51. The main influencing factors of water-retention capacity in the soil layer were non-capillary porosity and soil depth(R2=0.61), the influencing coefficients were 0.60 and 0.38, respectively. This study verifies the simulation of the water balance model or inversion of remote sensing of the water-retention capacity at the site scale, and provides scientific basis for further study of the impact of global change on water retention.

关键词： meta-analysis path analysis water retention Beijing-Tianjin-Hebei region

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Progress on spatial prediction methods for soil particle-size fractions

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Journal of Geographical Sciences 2023年第7期33卷 1553-1566页

作者： SHI Wenjiao ZHANG Mo Key Laboratory of Land Surface Pattern and Simulation of CAS Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China

Soil particle-size fractions(PSFs),including three components of sand,silt,and clay,are very improtant for the simulation of land-surface process and the evaluation of ecosystem *** spatial prediction of soil PSFs can help better understand the simulation processes of these *** soil PSFs are compositional data,there are some special demands such as the constant sum(1 or 100%) in the interpolation *** addition,the performance of spatial prediction methods can mostly affect the accuracy of the spatial ***,we proposed a framework for the spatial prediction of soil *** included log-ratio transformation methods of soil PSFs(additive log-ratio,centered log-ratio,symmetry log-ratio,and isometric log-ratio methods),interpolation methods(geostatistical methods,regression models,and machine learning models),validation methods(probability sampling,data splitting,and cross-validation) and indices of accuracy assessments in soil PSF interpolation and soil texture classification(rank correlation coefficient,mean error,root mean square error,mean absolute error,coefficient of determination,Aitchison distance,standardized residual sum of squares,overall accuracy,Kappa coefficient,and Precision-Recall curve) and uncertainty analysis indices(prediction and confidence intervals,standard deviation,and confusion index).Moreover,we summarized several paths on improving the accuracy of soil PSF interpolation,such as improving data distribution through effective data transformation,choosing appropriate prediction methods according to the data distribution,combining auxiliary variables to improve mapping accuracy and distribution rationality,improving interpolation accuracy using hybrid models,and developing multi-component joint *** the future,we should pay more attention to the principles and mechanisms of data transformation,joint simulation models and high accuracy surface modeling methods for multi-components,as well as the combi

关键词： soil interpolation spatial accuracy geostatistics machine learning high accuracy surface modeling

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Quantitative attribution analysis of soil erosion in different geomorphological types in karst areas: Based on the geodetector method

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Journal of Geographical Sciences 2019年第2期29卷 271-286页

作者： WANG Huan GAO Jiangbo HOU Wenjuan Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research CAS University of Chinese Academy of Sciences

The formation mechanism and influencing factors identification of soil erosion are the core and frontier issues of current research. However, studies on the multi-factor synthesis are still relatively lacked. In this study, the simulation of soil erosion and its quantitative attribution analysis have been conducted in different geomorphological types in a typical karst basin based on the RUSLE model and the geodetector method. The influencing factors, such as land use type, slope, rainfall, elevation, lithology and vegetation cover, have been taken into consideration. Results show that the strength of association between the six influencing factors and soil erosion was notably different in diverse geomorphological types. land use type and slope were the dominant factors of soil erosion in the Sancha River Basin, especially for land use type whose power of determinant(q value) for soil erosion was much higher than other factors. The q value of slope declined with the increase of relief in mountainous areas, namely it was ranked as follows: middle elevation hill> small relief mountain> middle relief mountain. Multi-factors interactions were proven to significantly strengthen soil erosion, particularly for the combination of land use type with slope, which can explain 70% of soil erosion distribution. It can be found that soil erosion in the same land use type with different slopes(such as dry land with slopes of 5° and above 25°) or in the diverse land use types with the same slope(such as dry land and forest with a slope of 5°), varied much. These indicate that prohibiting steep slope cultivation and Grain for Green Project are reasonable measures to control soil erosion in karst areas. Based on statistics of soil erosion difference between diverse stratifications of each influencing factor, results of risk detector suggest that the amount of stratification combinations with significant difference accounted for 55% at least in small relief mountain and middle relief

关键词： soil erosion distribution influencing factors RUSLE model geodetector karst Sancha River basin

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patterns and trends in grain self-sufficiency on the Tibetan Plateau during 1985–2016

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Journal of Geographical Sciences 2020年第10期30卷 1590-1602页

作者： SHI Wenjiao LU Changhe SHI Xiaoli CUI Jiaying Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China Key Laboratory of Environmental Evolvement and Ecological Construction of Hebei Province College of Resources and Environment SciencesHebei Normal UniversityShijiazhuang 050024China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China

Capacity for grain self-sufficiency on the Tibetan Plateau(TP)is an important basis for ensuring social stability and regional ***,based on county-level statistical data for population,grain production and consumption,we analyzed patterns and trends in grain supply and demand at regional,provincial,and county levels on the TP between 1985 and *** applied two indices to evaluate capacity for grain self-sufficiency and found that the regional average self-sufficiency rate increased quickly by 1.97%/a since 1989,reaching 173.03%on the plateau over the period between 2010 and *** indicates that grain supply in this region is able to fully meet *** addition,all provinces apart from Xinjiang exhibited similar increasing trends,attaining grain self-sufficiency during 2010–***,59%of counties attained grain self-sufficiency over this period,mainly distributed in southern Tibet,in the Sichuan-Tibet junction area,and in eastern Qinghai Province.A number of gaps in grain supply and demand occurred within the headwater regions of the Yangtze and Yellow rivers as well as on the Qiangtang *** self-sufficiency significantly increased over the study period in 36%of counties,mainly distributed in the agricultural areas of southeastern Tibet and in eastern *** the whole plateau,capacity for grain self-sufficiency substantially increased between 1985 and 2016,although serious spatial imbalances remain.

关键词： Tibetan Plateau grain county scale self-sufficiency spatiotemporal distribution

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Advances in terrestrial system research in China

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Journal of Geographical Sciences 2016年第7期26卷 791-802页

作者：吴绍洪尹云鹤郑度杨勤业邓浩宇 Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research CAS University of Chinese Academy of Sciences

land surface is of spatial-temporal heterogeneity. Terrestrial system（TS） comprehensively studies on land surface and physical regionalization objectively describes geographical zonation of the system. China has a vast area with apparent spatial variations in resources and environmental conditions, which highly influence on socio-economic development. In this paper, progress of the TS studies in China is overviewed and research priorities in the near future are prospected. Since the 1950 s, China has paid great attention to the TS study as its socio-economic development, and conducted research on physical geographical regionalization, eco-geographical regionalization and comprehensive regionalization. Along with the deepening of global change research, dynamics of TS have been highly concerned. During the studies, methodology has been developed from qualitative research of integration of experts＇ brainpower gradually to quantitative research based on field observation and experiments of the natural processes, including physical, chemical and biological processes, as well as application of information technology and mathematical simulation. In the near future, TS would combine with the ideology, objectives and key researches of Future Earth program, to focus on the mechanism and regional effects of interaction among land surface elements, the response of TS to global change, the quantitative recognition on regional unit boundary, and the application to TS in sustainable socio-economic development.

关键词： terrestrial system differentiation rules global change sustainable development China

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