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Climate-Vegetation Coverage Interactions in the Hengduan Mountains Area, Southeastern Tibetan Plateau, and Their Downstream Effects
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作者 Congxi FANG Jinlei CHEN +4 位作者 Chaojun OUYANG Lu WANG Changfeng SUN Quan ZHANG Jun WEN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第4期701-716,共16页
Little is known about the mechanism of climate-vegetation coverage coupled changes in the Tibetan Plateau(TP)region,which is the most climatically sensitive and ecologically fragile region with the highest terrain in ... Little is known about the mechanism of climate-vegetation coverage coupled changes in the Tibetan Plateau(TP)region,which is the most climatically sensitive and ecologically fragile region with the highest terrain in the world.This study,using multisource datasets(including satellite data and meteorological observations and reanalysis data)revealed the mutual feedback mechanisms between changes in climate(temperature and precipitation)and vegetation coverage in recent decades in the Hengduan Mountains Area(HMA)of the southeastern TP and their influences on climate in the downstream region,the Sichuan Basin(SCB).There is mutual facilitation between rising air temperature and increasing vegetation coverage in the HMA,which is most significant during winter,and then during spring,but insignificant during summer and autumn.Rising temperature significantly enhances local vegetation coverage,and vegetation greening in turn heats the atmosphere via enhancing net heat flux from the surface to the atmosphere.The atmospheric heating anomaly over the HMA thickens the atmospheric column and increases upper air pressure.The high pressure anomaly disperses downstream via the westerly flow,expands across the SCB,and eventually increases the SCB temperature.This effect lasts from winter to the following spring,which may cause the maximum increasing trend of the SCB temperature and vegetation coverage in spring.These results are helpful for estimating future trends in climate and eco-environmental variations in the HMA and SCB under warming scenarios,as well as seasonal forecasting based on the connection between the HMA eco-environment and SCB climate. 展开更多
关键词 Hengduan mountains area normalized difference vegetation index climate change net heat flux downstream effects
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Seismic response of a mid-story isolated structure considering SSI in mountainous areas under long-period earthquakes
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作者 Wan Feng Qin Shengwu +7 位作者 Liu Dewen Zhao Tiange Zheng Yanping Shan Hang Li Zhiang Peng Fusong Xu Jingran Lei Min 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期151-161,共11页
At present,there is not much research on mid-story isolated structures in mountainous areas.In this study,a model of a mid-story isolated structure considering soil-structure interaction(SSI)in mountainous areas is es... At present,there is not much research on mid-story isolated structures in mountainous areas.In this study,a model of a mid-story isolated structure considering soil-structure interaction(SSI)in mountainous areas is established along with a model that does not consider SSI.Eight long-period earthquake waves and two ordinary earthquake waves are selected as inputs for the dynamic time history analysis of the structure.The results show that the seismic response of a mid-story isolated structure considering SSI in mountainous areas can be amplified when compared with a structure that does not consider SSI.The structure response under long-period earthquakes is larger than that of ordinary earthquakes.The structure response under far-field harmonic-like earthquakes is larger than that of near-fault pulse-type earthquakes.The structure response under near-fault pulse-type earthquakes is larger than that of far-field non-harmonic earthquakes.When subjected to long-period earthquakes,the displacement of the isolated bearings exceeded the limit value,which led to instability and overturning of the structure.The structure with dampers in the isolated story could adequately control the nonlinear response of the structure,effectively reduce the displacement of the isolated bearings,and provide a convenient,efficient and economic method not only for new construction but also to retrofit existing structures. 展开更多
关键词 SSI in mountainous areas long-period earthquakes mid-story isolated structure structural dynamic analysis
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Dry Breeding and Dry Planting Techniques for Indica Hybrid Rice in Karst Mountain Areas of Gejiu City
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作者 Guifen WANG Wei SHI 《Plant Diseases and Pests》 2024年第2期34-36,共3页
Based on the arable land situation in Gejiu City,upland dry planting of indica hybrid rice is being expanded in Karst mountain areas with a rainfall of over 1400 mm and an altitude of 1100-1600 m to develop grain prod... Based on the arable land situation in Gejiu City,upland dry planting of indica hybrid rice is being expanded in Karst mountain areas with a rainfall of over 1400 mm and an altitude of 1100-1600 m to develop grain production.This paper gives a specific description of hybrid rice upland dry seedling technology,upland transplanting technology,fertilization technology,field management,weed prevention and control technology,and disease and pest control. 展开更多
关键词 Karst mountain area Hybrid rice Dry breeding Dry planting
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Spatio-temporal Evolution and Optimization of Landscape Ecological Risk in Karst Mountainous Areas
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作者 Fangfang DENG Zhongfa ZHOU +4 位作者 Denghong HUANG Yang ZHANG Fuxianmei ZHANG Shuanglong DU Yue YANG 《Meteorological and Environmental Research》 2024年第1期16-26,共11页
[Objective]The ecological vulnerability and landscape ecological risk of karst mountainous areas have increased as a result of enhanced disturbance of natural resources by human activities.This paper aimed to explore ... [Objective]The ecological vulnerability and landscape ecological risk of karst mountainous areas have increased as a result of enhanced disturbance of natural resources by human activities.This paper aimed to explore the characteristics of ecological risk evolution under different landscape patterns in the region,with a view to providing reference for land classification protection,sustainable use of resources and regional ecological risk optimization in karst mountainous areas.[Method]Taking Huangping County,a typical karst mountainous area,as an example,eight evaluation factors of natural and landscape patterns were selected to construct a landscape ecological risk evaluation model,to quantitatively explore the spatio-temporal evolution of landscape ecological risk and the trend of risk level transfer in the study area from^(2)010-2018,and to reveal the complex relationship between ecological risk and topography in karst mountainous areas.[Result]①From 2010 to 2018,land use types changed to different degrees,with the most amount of woodland transferred out(1627.37 hm^(2))and the most amount of construction land transferred in(1303.93 hm^(2));a total of 3552.31 hm^(2) of land was transferred,with a change ratio of 2.13%,and there was a significant conversion between construction land,arable land,and woodland.②From 2010 to 2018,the landscape ecological risk in the study area changed significantly,and the landscape ecological risk index decreased from 0.3441 to 0.1733,showing an upward and then downward trend;the landscape ecological risk of the whole region was dominated by low-risk and lower-risk zones,and the ecological risk level generally shifted from a high level to a low level,and the ecological environment was improved.③There was a negative correlation between ecological risk and topographic position,and high-risk zones were mainly distributed among low topographic zones;with the change of time,the advantage of risk level for the selection of topography was gradually weakened,and the influence of anthropogenic factors on the ecological risk of the landscape was becoming more and more prominent.[Conclusion]This paper can provide theoretical basis for land use optimization and ecological protection in karst mountainous areas. 展开更多
关键词 Karst mountainous area Landscape pattern Landscape ecological risk index Terrain distribution index
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Performance evaluation of CLM5.0 in simulating liquid soil water in high mountainous area,Northwest China
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作者 ZHANG Lan-hui NING Feng-wei +2 位作者 BAI Xu-liang ZENG Xuan HE Chan-sheng 《Journal of Mountain Science》 SCIE CSCD 2023年第7期1865-1883,共19页
The model performance in simulating soil water content(SWC) is crucial for successfully modeling earth’s system,especially in high mountainous areas.In this study,the performance of Community Land Model 5.0(CLM5.0) i... The model performance in simulating soil water content(SWC) is crucial for successfully modeling earth’s system,especially in high mountainous areas.In this study,the performance of Community Land Model 5.0(CLM5.0) in simulating liquid SWC was evaluated against observations from nine in-situ sites in the upper reach of the Heihe River Watershed(HRW),Northwest China.The CLM5.0 shows reliable performance in the study area with correlation coefficients(R) ranging between 0.79–0.93,root mean standard errors(RMSE)ranging between 0.044–0.097 m^(3)/m^(3),and the mean bias(BIAS) ranging between-0.084–0.061 m^(3)/m^(3).The slightly worse performance of CLM5.0 than CLM4.5 on alpine meadow and grassland is mainly caused by the revised canopy interception parameterization.The CLM5.0 overestimates interception and underestimates evapotranspiration(ET) on both alpine meadow and grassland during the growth period.The systematical overestimations at all the grassland sites indicate that the underestimation of ET is much larger than the overestimation of interception on grassland during growth period,while the errors of simulated interception and ET are partially canceled out on alpine meadow.Moreover,the underestimation of ET is more responsible for the overestimation of SWC than the overestimation of interception in the high mountainous area.It is necessary to estimate reasonable empirical parameter α(proportion of leaf water collection area) in interception parameterization scheme and further improve the dry surface layerbased soil evaporation resistance parameterization introduced in CLM5.0 in future researches.The performance of CLM5.0 is better under completely frozen stage than thawing stage and freezing stage,because of low variations of liquid SWC caused by extremely low hydraulic conductivity of soils.The underestimation of liquid SWC under frozen state is caused by underestimation of soil temperature,which leads to more ice mass and less liquid water in total water content. 展开更多
关键词 Performance evaluation Soil water content CLM5.0 EVAPOTRANSPIRATION High mountainous area
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Spatiotemporal Interaction Between Rural Settlements and Cultivated Land in Karst Mountainous Area,China
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作者 LIN Feifei CHENG Peng KONG Xuesong 《Chinese Geographical Science》 SCIE CSCD 2023年第5期946-965,共20页
Settlements and cultivated land are important production and living spaces in promoting rural revitalization.However,few studies have explored the relationship between rural settlements and cultivated land from spatio... Settlements and cultivated land are important production and living spaces in promoting rural revitalization.However,few studies have explored the relationship between rural settlements and cultivated land from spatiotemporal interaction perspective.This paper analyzed the spatiotemporal conversion and the interactive mechanism between rural settlements and cultivated land in a karst mountainous area(Qixingguan District of Guizhou Province)with fragile ecological environment in China during 2009–2018.The results showed that the expansion of rural settlements and the loss of cultivated land coexisted in Qixingguan District.Only 2.68%of the new cultivated land was reclaimed from rural settlements,whereas 85.45%of the new rural settlements occupied cultivated land.Six spatial expansion modes of rural settlements when occupying cultivated land were identified.Among these six modes,the area of the edge-expansion&along traffic roads(EA)mode accounted for 52.75%.The occupation by rural settlements made the cultivated land landscape more fragmented.The area ratio index of cultivated land to rural settlements(ARICR)of Qixingguan District averaged 18.75in 2009 and 17.21 in 2018,respectively.The ARICR reduced in all township administrative regions.Cultivated land with suitable slope condition for farming or without rocky desertification was more likely to be occupied by rural settlements.The probability of cultivated land occupied by rural settlements increased with the decrease of the distance to traffic roads,towns,and old rural settlements.The better the economic and social development of the township administrative regions,the more the ARICR decreased,while the richer the agricultural resources and the better the rural development of the township administrative regions,the less the ARICR decreased.The optimal reconstruction path of rural settlements,the comprehensive conservation path of cultivated land and the urban-rural integration development path in karst mountainous area were proposed.The findings would contribute to our understanding of the spatiotemporal interaction between rural settlements and cultivated land,and would provide a theoretical basis for promoting the coordinated development of rural man-land relationship and rural revitalization in karst areas. 展开更多
关键词 cultivated land rural settlements landscape pattern logistic regression geographical detector karst mountainous area
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Can Multiple Livelihood Interventions Improve Livelihood Resilience of Out-of-poverty Farmers in Mountain Areas?A Case Study of Longnan Mountain Area,China
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作者 WANG Rong ZHAO Xueyan 《Chinese Geographical Science》 SCIE CSCD 2023年第5期898-916,共19页
Clarifying the impact of livelihood interventions on the livelihood resilience of farmers in undeveloped mountain areas can not only optimize interventions,but also provide experiential support for global poverty alle... Clarifying the impact of livelihood interventions on the livelihood resilience of farmers in undeveloped mountain areas can not only optimize interventions,but also provide experiential support for global poverty alleviation.To analyze the impact of multiple livelihood interventions on livelihood resilience,we constructed an analytical framework and analyzed the enjoyment of livelihood interventions and the heterogeneity of livelihood resilience among out-of-poverty farmers in the Longnan mountain areas,China.Then,we studied the impact of intervention intensity on livelihood resilience through the multiple linear regression model.The results revealed that:1)the livelihood interventions enjoyed by out-of-poverty farmer in mountain areas were multiple.The proportion of farmers enjoyed diversified livelihood interventions was in descending order of high mountain areas,semi-mountain area and Chuanba valley areas.2)The overall livelihood resilience of farmers in Longnan mountain areas was generally low,with an average of 0.299.There were significant differences in the livelihood resilience of farmers across different geographic areas in the study area and types of interventions.3)The effects of industry interventions,employment interventions and education interventions were significant.The endogenous power of farmers not only had a significant positive effect on livelihood resilience,but also positively moderated the impact of the intensity of interventions on livelihood resilience.In addition,the household dependency ratio and the average altitude of the village area had a significant negative impact on their livelihood resilience. 展开更多
关键词 livelihood resilience livelihood interventions FARMER Longnan mountain area China
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Moderate scale and realization potential of new citrus-planting business entities in hilly and mountainous areas in China
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作者 ZHANG Xuan-yun ZHANG Shi-chao +3 位作者 LIU Jing-yu RAN Na ZHANG Xiang NING Qi-wen 《Journal of Mountain Science》 SCIE CSCD 2023年第8期2315-2343,共29页
The natural and economic conditions of agricultural resources vary greatly in China,especially in hilly and mountainous areas.The phenomenon of land fragmentation has become increasingly prominent,so that large-scale ... The natural and economic conditions of agricultural resources vary greatly in China,especially in hilly and mountainous areas.The phenomenon of land fragmentation has become increasingly prominent,so that large-scale operations cannot be fully achieved in a short period of time,and the centralized and continuous scale of operations cannot be realized in China.In addition,with increasingly strict farmland protection and agricultural land use control systems,the issues of nongrain production and nonagricultural cultivated land use have become increasingly restricted.Thus,it is quite necessary to determine the appropriate scale of operations and the means to achieve moderately scaled operations for the new business entities.On the basis of microsurvey data for 108 new citrus-planting business entities in the modern agricultural park in the Chongqing's Jiangjin District,an area with long citrus-planting history,we measured the moderate scale of new citrus-planting business entities to maximize profit using a translog growth model.According to the projection pursuit model,we evaluated the suitability conditions of citrus planting in garden land,woodland,grassland,and general cultivated land in the study area.We then explored the potential for new moderate-scale business entities within different farming radii.The results showed that large-scale planting conditions of citrus in garden land,forest land,grassland,and general cultivated land in the study area were suitable,and the proportion of high-suitable and mediumsuitable land was 73.42%.Under the existing social and economic conditions,the moderate scale of new citrus-planting business entities in the study area was 1.8–2.7 hm^(2).In particular,its rankings from large to small were agricultural enterprises(17.19–25.78 hm^(2)),farmer cooperatives(16.88–25.33 hm^(2)),big growers and breeders(6.39–9.59 hm^(2)),and family farms(5.02–7.53 hm^(2)).In the sample of 108 households,only 47.22%of the entities achieved moderate-scale operation,of which 25%of the entities achieved a scale greater than moderate operation.However,52.78%of the entities achieved a scale of less than moderate operation.These entities would have to transfer the surrounding adjacent garden land,forest land,grassland,or general cultivated land to achieve largescale land management.The land area of the adjacent gardens in a 1000 m farming radius could meet the moderate-scale operation demand of the vast majority of new business entities.For the vast majority of new business entities,the land area of the adjacent woodland,grassland,and general cultivated land could supplement the garden land to achieve moderate-scale operation in a 500 m farming radius.If the land area with moderate suitability and high suitability is prioritized,the land area in the adjacent gardens in the 1000 m farming radius could meet the moderate-scale operation demand for the vast majority of new business entities.Within the 500 m farming radius,the vast majority of new business entities have achieved moderate-scale operations if the land area adjacent to forest land,grassland,and general arable land was supplemented by gardens;however,a few entities could not achieve moderate-scale operations.From the village perspective,gardens were prioritized.Sixteen villages had planting areas and planting suitability that exceeded the average level of the study area,accounting for 23.53%.If combined with the reserve potential of the garden land,eight villages could improve their potential,accounting for 11.76%.Therefore,the conditions of large-scale citrus planting in the study area should be further improved,and the scale expansion of new citrus-planting business entities should receive additional scientific guidance. 展开更多
关键词 Land management Hilly and mountainous areas Agricultural business entities Moderate operation scale Agricultural land resources Realizing potential
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Abandoned land identification in karst mountain area based on time series SAR characteristics at geo-parcels scale
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作者 ZHOU Zhong-fa WANG Ling-yu +6 位作者 CHEN Quan LUO Jian-cheng ZHAO Xin ZHANG Shu ZHANG Wen-hui LIAO Juan LYU Zhi-jun 《Journal of Mountain Science》 SCIE CSCD 2023年第3期792-809,共18页
Mapping abandoned land is very important for accurate agricultural management.However,in karst mountainous areas,continuous high-resolution optical images are difficult to obtain in rainy weather,and the land is fragm... Mapping abandoned land is very important for accurate agricultural management.However,in karst mountainous areas,continuous high-resolution optical images are difficult to obtain in rainy weather,and the land is fragmented,which poses a great challenge for remote sensing monitoring of agriculture activities.In this study,a new method for identifying abandoned land is proposed:firstly,a few Google Earth images are used to transform arable land into accurate vectorized geo-parcels;secondly,a time-series data set was constructed using Sentinel-1A Alpha parameters for 2020 on each farmland geoparcel;thirdly,the semi-variation function(SVF)was used to analyze the spatial-temporal characteristics,then identify abandoned land.The results show:(1)On the basis of accurate spatial information and boundary of farmland land,the SAR time-series dataset reflects the structure and time-series response.abandoned land with an accuracy of 80.25%.The problem of remote sensing monitoring in rainy regions and complex surface areas is well-resolved.(2)The spatial heterogeneity of abandoned land is more obvious than that of cultivated land within geoparcels.The step size for significant changes in the SVF of abandoned land is shorter than that of cultivated land.(3)The SVF time sequence curve presented a strong peak feature when farmland was abandoned.This reveals that the internal spatial structure of abandoned land is more disordered and complex.It showed that time-series variations of spatial structure within cultivated land have broader applications in remote sensing monitoring of agriculture in complex imaging environments. 展开更多
关键词 Sentinel-1 SAR Abandoned farmland Semi variogram function Farmland geo parcel Time seriescharacteristics Texture feature Karst mountainous area
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Growth behavior and resource potential evaluation of gas hydrate in core fractures in Qilian Mountain permafrost area, Qinghai-Tibet Plateau
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作者 Qing-guo Meng Chang-ling Liu +5 位作者 Zhen-quan Lu Xi-luo Hao Cheng-feng Li Qing-tao Bu Yun-kai Ji Jia-xian Wang 《China Geology》 CAS CSCD 2023年第2期208-215,共8页
The Qilian Mountain permafrost area located in the northern of Qinghai-Tibet Plateau is a favorable place for natural gas hydrate formation and enrichment,due to its well-developed fractures and abundant gas sources.U... The Qilian Mountain permafrost area located in the northern of Qinghai-Tibet Plateau is a favorable place for natural gas hydrate formation and enrichment,due to its well-developed fractures and abundant gas sources.Understanding the formation and distribution of multi-component gas hydrates in fractures is crucial in accurately evaluating the hydrate reservoir resources in this area.The hydrate formation experiments were carried out using the core samples drilled from hydrate-bearing sediments in Qilian Mountain permafrost area and the multi-component gas with similar composition to natural gas hydrates in Qilian Mountain permafrost area.The formation and distribution characteristics of multi-component gas hydrates in core samples were observed in situ by X-ray Computed Tomography(X-CT)under high pressure and low temperature conditions.Results show that hydrates are mainly formed and distributed in the fractures with good connectivity.The ratios of volume of hydrates formed in fractures to the volume of fractures are about 96.8%and 60.67%in two different core samples.This indicates that the fracture surface may act as a favorable reaction site for hydrate formation in core samples.Based on the field geological data and the experimental results,it is preliminarily estimated that the inventory of methane stored in the fractured gas hydrate in Qilian Mountain permafrost area is about 8.67×1013 m3,with a resource abundance of 8.67×108 m3/km2.This study demonstrates the great resource potential of fractured gas hydrate and also provides a new way to further understand the prospect of natural gas hydrate and other oil and gas resources in Qilian Mountain permafrost area. 展开更多
关键词 Gas hydrate Growth behavior Core fracture Rock Quality Designation Resource potential evaluation Engineering Oil and gas exploration Qilian mountain permafrost area Qinghai-Tibet Plateau
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Applications of AnnAGNPS Model for Sediment and Nutrient Loadings for Funiu Mountain Area, China
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作者 TIAN Yaowu LIU Yali +2 位作者 ZHANG Chulei ZHANG Zizheng LI Xiaolin 《Journal of Landscape Research》 2023年第5期85-88,共4页
The main goal of this study was to evaluate the performance of AnnAGNPS(Annualized AGricultural NonPoint Source)pollution model,in calculating runoff,sediment loading and nutrient loadings for Funiu Mountain area.Most... The main goal of this study was to evaluate the performance of AnnAGNPS(Annualized AGricultural NonPoint Source)pollution model,in calculating runoff,sediment loading and nutrient loadings for Funiu Mountain area.Most of the model input parameters were sourced from Luanchuan Forest Ecology Station(LFES)in Funiu Mountain area.The data on 23 storms in 2018 was used to calibrate the model and the data on 33 storms in 2019 for validation.The whole evaluation consisted of determining the coefficient of determination(R^(2)),Nash-Sutcliffe coefficient of efficiency(E),and the percentage volume error(VE).Results showed that the runoff volumes were underpredicted by 5.0%with R^(2) of 0.93(P<0.05)during calibration and underpredicted by 5.3%with R^(2) of 0.90(P<0.05)during validation.But sediment loading was able to produce a moderate result.The model underpredicted the daily sediment loading by 15.1%with R^(2) of 0.63(P<0.05)during calibration and 13.5%with R^(2) of 0.66(P<0.05)during validation.Nitrogen loading was overpredicted by 20.3%with R^(2)=0.68(P<0.05),and phosphorus loading performance was slightly poor with R^(2)=0.65(P<0.05)during validation.In general,the model performed well in simulating runoff compared to sediment loading and nutrient loadings. 展开更多
关键词 AnnAGNPS model RUNOFF Sediment loading Nutrient loadings Funiu mountain area PERFORMANCE
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Preliminary Study on Forest Fire Prevention and Extinguishing in Townships in the Southern Mountainous Areas of Zhejiang Province:A Case Study of Lishui
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作者 Dalin WANG Ming LUO +2 位作者 Xiaobing YANG Siwei ZHENG Jian DENG 《Meteorological and Environmental Research》 2023年第6期53-57,共5页
Forest fires seriously threaten forestry resources and the life and property safety of people in mountainous areas of Lishui City. In this paper, a fire prevention concept with refined forecast and early warning of fo... Forest fires seriously threaten forestry resources and the life and property safety of people in mountainous areas of Lishui City. In this paper, a fire prevention concept with refined forecast and early warning of forest fire danger weather ratings in townships as the starting point, satellite real-time observation of fire spots, monitoring of the Internet of Things and other high-tech products as an implementation means, and strengthening forest fire prevention equipment and personnel in townships as a guarantee was established. The command system for rapid emergency response by cities, counties and townships should be improved. During the forest fire prevention period, fire sources should be strictly controlled, and the basic principles of forest fire fighting in townships should be implemented into the actual fire prevention and fire fighting work to eliminate forest fires in time at the initial stage and before the disaster. 展开更多
关键词 mountainous areas of southern Zhejiang Townships Forest fire danger
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Using satellite-derived land surface temperatures to clarify the spatiotemporal warming trends of the Alborz Mountains in northern Iran
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作者 ROSHAN Gholamreza SARLI Reza +2 位作者 GHANGHERMEH Abdolazim TAHERIZADEH Mehrnoosh NIKNAM Arman 《Journal of Mountain Science》 SCIE CSCD 2024年第2期449-469,共21页
The Alborz Mountains are some of the highest in Iran,and they play an important role in controlling the climate of the country’s northern regions.The land surface temperature(LST)is an important variable that affects... The Alborz Mountains are some of the highest in Iran,and they play an important role in controlling the climate of the country’s northern regions.The land surface temperature(LST)is an important variable that affects the ecosystem of this area.This study investigated the spatiotemporal changes and trends of the nighttime LST in the western region of the Central Alborz Mountains at elevations of 1500-4000 m above sea level.MODIS data were extracted for the period of 2000-2021,and the Mann-Kendall nonparametric test was applied to evaluating the changes in the LST.The results indicated a significant increasing trend for the monthly average LST in May-August along the southern aspect.Both the northern and southern aspects showed decreasing trends for the monthly average LST in October,November,and March and an increasing trend in other months.At all elevations,the average decadal change in the monthly average LST was more severe along the southern aspect(0.60°C)than along the northern aspect(0.37°C).The LST difference between the northern and southern aspects decreased in the cold months but increased in the hot months.At the same elevation,the difference in the lapse rate between the northern and southern aspects was greater in the hot months than in the cold months.With increasing elevation,the lapse rate between the northern and southern aspects disappeared.Climate change was concluded to greatly decrease the difference in LST at different elevations for April-July. 展开更多
关键词 Global warming mountainous areas Lapse rate Surface air temperatures ALBORZ
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Analysis of Damage Pattern of Road Bridge Landslide in Mountainous Area
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作者 Zhongyang Sun Wuhao Chen 《Journal of World Architecture》 2023年第3期38-45,共8页
Through on-site defect investigation,special inspection,and finite element simulation calculation of a high-speed upper-span(30+32+30)m prestressed concrete box girder bridge,the overall sliding force of the bridge on... Through on-site defect investigation,special inspection,and finite element simulation calculation of a high-speed upper-span(30+32+30)m prestressed concrete box girder bridge,the overall sliding force of the bridge on the right side of platform 0#is analyzed.In this situation,typical defects such as overall girder slippage,support dislocation,pier column deviation,and pier bottom side cracks have occurred in the overpass.At the same time,combined with simulation calculation analysis,it is interpreted that the 0#and 1#foundation has been damaged at a certain position below the ground line.The occurrence of broken piles has provided a reliable basis for the later reinforcement and maintenance of the bridge and ideas for emergency inspection and analysis of bridges damaged by the same type of landslides. 展开更多
关键词 LANDSLIDE Overpass in mountainous area Damage pattern Special inspection Simulation calculation analysis
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Mountain Highway Design Based on New Green Design Concepts
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作者 Zhuang Hu Yazhou Liu 《Journal of World Architecture》 2024年第2期118-122,共5页
This article analyzes the implementation of new environmentally friendly design practices in the construction of mountain highways.It covers topics such as green highway design concepts,alignment principles,and green ... This article analyzes the implementation of new environmentally friendly design practices in the construction of mountain highways.It covers topics such as green highway design concepts,alignment principles,and green practices specifically for mountainous highway design.This analysis aims to provide useful insights for creating green mountain highways that meet the demands of modern times. 展开更多
关键词 mountainous areas HIGHWAYS Green design concepts
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NUMERICAL SIMULATION ON THE WIND FIELD STRUCTURE OF A MOUNTAINOUS AREA BESIDE SOUTH CHINA SEA DURING THE LANDFALL OF TYPHOON MOLAVE 被引量:5
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作者 李磊 陈柏纬 +2 位作者 胡非 张立杰 柳艳香 《Journal of Tropical Meteorology》 SCIE 2014年第1期66-73,共8页
Leveraging the commercial CFD software FLUENT,the fine-scale three-dimensional wind structure over the Paiya Mountains on the Dapeng Peninsula near Shenzhen,a city on the seashore of South China Sea,during the landfal... Leveraging the commercial CFD software FLUENT,the fine-scale three-dimensional wind structure over the Paiya Mountains on the Dapeng Peninsula near Shenzhen,a city on the seashore of South China Sea,during the landfall of Typhoon Molave has been simulated and analyzed.Through the study,a conceptual wind structure model for mountainous areas under strong wind condition is established and the following conclusions are obtained as follows:(1)FLUENT can reasonably simulate a three-dimensional wind structure over mountainous areas under strong wind conditions;(2)the kinetic effect of a mountain can intensify wind speed in the windward side of the mountain and the area over the mountain peak;and(3)in the leeward side of the mountain,wind speed is relatively lower with relatively stronger wind shear and turbulence. 展开更多
关键词 TYPHOON numerical simulation wind structure SHENZHEN mountainous area
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The simulation of LUCC based on Logistic-CA-Markov model in Qilian Mountain area, China 被引量:7
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作者 HaiJun Wang XiangDong Kong Bo Zhang 《Research in Cold and Arid Regions》 CSCD 2016年第4期350-358,共9页
The Qilian mountain area was examined for using the Logistic-CA-Markov coupling model combined with GIS spatial analyst technology to research the transformation of LUCC, driving force system and simulate future tende... The Qilian mountain area was examined for using the Logistic-CA-Markov coupling model combined with GIS spatial analyst technology to research the transformation of LUCC, driving force system and simulate future tendency of variation. Results show that: (1) Woodland area decreased by 12.55%, while grassland, cultivated land, and settlement areas increased by 0.22%, 7.92%, and 0.03%, respectively, from 1986 to 2014. During the period of 1986 to 2000, forest degradation in the middle section of the mountain area decreased by 1,501.69 km2. Vegetation cover area improved, with a net increase of grassland area of 38.12 km2 from 2000 to 2014. (2) For constructing the system driving force, the best simulation scale was 210m×210m. Based on logistic regression analysis, the contribution (weight) of composite driving forces to land use and cover change was obtained, and the weight value was more objectively compared with AHP and MCE method. (3) In the natural scenarios, it is predicted that land use and cover distribution maps of Qilian mountain area in 2028 and 2042, and the Lee-Sallee index test was adopted. Over the next 27 years (2015-2042), farmland, woodland, grassland, settlement areas show an increasing trend, especially settlements with an obvious change of 0.56%. The area of bare land will decrease by 0.89%. Without environmental degradation, tremendous structural change of LUCC will not occur, and typical characteristic of the vertical zone of the mountain would remain. Farmland and settlement areas will increase, but only in the vicinity of Qilian and Sunan counties. 展开更多
关键词 Qilian mountain area LUCC Logistic-CA-Markov model simulation and prediction
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Disaster Reduction Decision Support System Against Debris Flows and Landslides Along Highway in Mountainous Area 被引量:4
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作者 Li Fa-bin, Wei Fang-qiang, Cui Peng, Zhou Wan-cunInstitute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu, 610041, Sichuan, China 《Wuhan University Journal of Natural Sciences》 CAS 2003年第03B期1012-1020,共9页
Highways in mountainous areas are easy to be damaged by such natural disasters as debris flows and landslides and disaster reduction decision support system (DRDSS) is one of the important means to mitigate these disa... Highways in mountainous areas are easy to be damaged by such natural disasters as debris flows and landslides and disaster reduction decision support system (DRDSS) is one of the important means to mitigate these disasters. Guided by the theories and technologies of debris flow and landslide reduction and supported by geographical information system (GIS), remote sensing and database techniques, a DRDSS against debris flow and landslide along highways in mountainous areas has been established on the basis of such principles as pertinence, systematicness, effectiveness, easy to use, open and expandability. The system consists of database, disaster analysis models and decisions on reduction of debris flows and landslides, mainly functioning to zone disaster dangerous degree, analyze debris flow activity, simulate debris flow deposition and diffusion, analyze landslide stability, select optimal highway renovation scheme and plan disaster prevention and control engineering. This system has been applied successfully to the debris flow and landslide treatment works along Palongzangbu Section of Sichuan-Tibet Highway. 展开更多
关键词 decision support system disaster reduction debris flow LANDSLIDE highway in mountainous areas
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Function of Rural Settlement Complex Ecosystem in Mountain Area:A Case Study of Raosi Village of Zuogong County,Tibet 被引量:4
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作者 LIU Shaoquan CHEN Guojie 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第4期945-950,共6页
Using energy analysis,the quantifying evaluation and study method on production, living and ecology functions and their sustainability of rural settlement ecosystem in mountain area is established with these energy in... Using energy analysis,the quantifying evaluation and study method on production, living and ecology functions and their sustainability of rural settlement ecosystem in mountain area is established with these energy index such as export of labor and products, export of water resource, internal energy reserve, energy consumption for human living, net energy of ecosystem function and net internal reserve. Taking rural settlement Raosi Village in Hengduan Mountains as a case study, and on the basis of the synthetic research into the ecological process of the complex ecosystem, the study shows that energy costs of production, human living and ecology functions are separately taking 1.36%, 13.59% and 85. 05% of the gross ecosystem functions, and the exertions of production and human living functions are close to a high-point state on the present using level of energy in the settlement. The study also shows that the most important function of a rural settlement in mountain area is its ecological rather productive function. 展开更多
关键词 mountain area rural settlement complex ecosystem ecosystem function energy analysis
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Estimation of evapotranspiration with drainage lysimeters in the Taihang Mountain area,China 被引量:3
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作者 YANG Fan ZHANG Wan-jun 《Forestry Studies in China》 CAS 2009年第4期219-224,共6页
In this research, the evapotranspiration (ET) of three native vegetation communities were measured using drainage lysime- ters in the Taihang Mountain area, China. They are a local grass, Themedajaponica, a local sh... In this research, the evapotranspiration (ET) of three native vegetation communities were measured using drainage lysime- ters in the Taihang Mountain area, China. They are a local grass, Themedajaponica, a local shrub, Vitex negundo var. heterophylla Rebd. and a mixture of both communities. The ET was measured using level lysimeters (with a slope of 0°) and slope lysimeters (with a slope of 25°). In general, the measured ET was higher in the level lysimeters than in the slope lysimeters because of the water loss of surface runoff from the slope lysimeter. The total ETs over the growing season for the grass, shrub, and the mixture were 730.4, 742.0 and 790.7 mm, respectively in the level lysimeters, and 535.5, 504.1 and 540.1 mm, respectively in the slope lysimeters. In addition, the monthly ET peaked in August and had close linear relationship with leaf area index. The drainage lysimeter is an effective tool to estimate plant ET in mountain areas. The results from this research would provide scientific information for the vegetation recovery and sustainable development of forestry in the TM areas. 展开更多
关键词 EVAPOTRANSPIRATION water balance drainage lysimeter leaf area index Taihang mountain area
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