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1A model for simulating the response of runoff from the mountainous watersheds of inland river basins in the arid area of northwest China to climatic changes显示文摘A model for simulating the response of monthly runoff from the mountainous watersheds to climatic changes is developed.The model is based on the modifications to the HBV runoff model, and therefore represents the characteristics and runoff generation processes of inland river basins in the arid area of northwest China. Taking the mountainous watershed of an inland river, the Heihe River originating from the Qilian Mountains and running through the Hexi Corridor as an example, the monthly runoff changes under different climate scenarios are simulated. The simulation indicates that, during the years from 1994 to 2030, if the annual mean air temperature increases by 0.5℃, and precipitation keeps unchanged, then the runoff of May and October will increase because of the increase of the snow melt runoff, but the runoff of July and August will decrease to some extent because of the increase of evaporation, and as a result, the annual runoff will decrease by 4%. If the precipitation still keeps unchanged,康尔泗 程国栋 蓝永超 金会军 1999Science China Earth Sciences1999,42,S1:45
2Carbon budgets of three temperate forest ecosystems in Dongling Mt.,Beijing,China显示文摘There is a general agreement that forest ecosystems in the Northern Hemisphere function as signifi-cant sinks for atmospheric CO2; however, their magnitude and distribution remain large uncertainties. In this paper, we report the carbon (C) stock and its change of vegetation, forest floor detritus, and mineral soil, annual net biomass increment and litterfall production, and respiration of vegetation and soils between 1992 to 1994, for three temperate forest ecosystems, birch (Betula platyphylla) forest, oak (Quercus liaotungensis) forest and pine (Pinus tabulaeformis) plantation in Mt. Dongling, Beijing, China. We then evaluate the C budgets of these forest ecosystems. Our results indicated that total C density (organic C per hectare) of these forests ranged from 250 to 300 t C ha-1, of which 35―54 t C ha-1 from vegetation biomass C and 209―244 t C ha-1 from soil organic C (1 m depth, including forest floor detritus). Biomass C of all three forests showed a net increase, with 1.33―3.55 t C ha-1 a-1 during the study period. Litterfall production, vegetation autotrophic respiration, and soil heterotrophic respira-tion were estimated at 1.63―2.34, 2.19―6.93, and 1.81―3.49 t C ha-1 a-1, respectively. Ecosystem gross primary production fluctuated between 5.39 and 12.82 t C ha-1 a-1, about half of which (46%―59%, 3.20―5.89 t C ha-1 a-1) was converted to net primary production. Our results suggested that pine forest fixed C of 4.08 t ha-1 a-1, whereas secondary forests (birch and oak forest) were nearly in balance in CO2 exchange between the atmosphere and ecosystems.FANG JingYun LIU GuoHua ZHU Biao WANG XiaoKe LIU ShaoHui 2007Science China Earth Sciences2007,50,1:17
3南方复杂山地三维地震勘探实践与效果分析显示文摘南方海相碳酸盐岩油气勘探历史较长,以前虽有所发现,但规模有限。近几年来,随着三维地震勘探技术的发展及其在南方复杂山地的大规模实施,中国石油化工股份有限公司相继在川东北地区海相油气勘探领域取得了巨大发现。勘探实践表明,三维地震勘探技术大幅度改善了该地区的地震资料品质,为解决复杂地质问题奠定了良好的资料基础,从而提高了碳酸盐岩储层预测和描述的精度,大大加快了油气勘探节奏。从普光大型气田的探明到元坝大型礁滩体的发现,充分表明三维地震勘探技术在南方复杂海相油气勘探中发挥了不可替代的作用。敬朋贵 殷厚成 陈祖庆 2010石油物探2010,49,5:12
4Evaluation of the SMOS and SMAP soil moisture products under different vegetation types against two sparse in situ networks over arid mountainous watersheds, Northwest China显示文摘Assessment of the suitability of satellite soil moisture products at large scales is urgently needed for numerous climatic and hydrological researches, particularly in arid mountainous watersheds where soil moisture plays a key role in landatmosphere exchanges. This study presents evaluation of the SMOS(L2) and SMAP(L2_P_E and L2_P) products against ground-based observations from the Upstream of the Heihe River Watershed in situ Soil Moisture Network(UHRWSMN) and the Ecological and Hydrological Wireless Sensor Network(EHWSN) over arid high mountainous watersheds, Northwest China.Results show that all the three products are reliable in catching the temporal trend of the in situ observations at both point and watershed scales in the study area. Due to the uncertainty in brightness temperature and the underestimation of effective temperature, the SMOS L2 product and both the SMAP L2 products show 'dry bias' in the high, cold mountainous area. Because of the more accurate brightness temperature observations viewing at a constant angle and more suitable estimations of single scattering albedo and optical depth, both the SMAP L2 products performed significantly better than the SMOS product.Moreover, comparing with station density of in situ network, station representation is much more important in the evaluation of the satellite soil moisture products. Based on our analysis, we propose the following suggestions for improvement of the SMOS and SMAP product suitability in the mountainous areas: further optimization of effective temperature; revision of the retrieval algorithm of the SMOS mission to reduce the topographic impacts; and, careful selection of in situ observation stations for better representation of in situ network in future evaluations. All these improvements would lead to better applicability of the SMOS and SMAP products for soil moisture estimation to the high elevation and topographically complex mountainous areas in arid regions.Lanhui ZHANG Chansheng HE Mingmin ZHANG Yi ZHU 2019Science China Earth Sciences2019,62,4:10
5中国山区农村土地利用转型及其对土地整治的政策启示(英文)显示文摘The cultivation of mountainous land results in water loss and soil erosion. With rapid urbanization and industrialization in China, labor emigration relieves the cultivation of mountainous areas in regions with high poverty and leads to a significant land use transition. This research built an analysis framework for 'land use transition – driving mechanism – effects –responses' for mountainous areas of China undergoing land use transition and then proposed the direction of mountainous land consolidation. The results showed that the turning point of land use morphology was the core of rural land use transition in mountainous areas. The expansion of cropland and the contraction of forestland have transitioned to the abandonment of cropland and the expansion of forestland;this transition was the main characteristic of the dominant land use change. Land marginalization and land ecological functional recovery were the main characteristics of the recessive land use transition in mountainous areas. Socioeconomic factors were the primary driving forces during land use transition in mountainous areas, with labor emigration being the most direct force. The rising costs of farming and the challenging living conditions causing labor emigration were fundamental driving forces. Rural land use transition in mountainous areas reduced the vulnerability of the ecological function of land ecosystems. The advantages and disadvantages of the socioeconomic effects should focus on rural development of mountainous areas as well as the livelihood of farmers;this should be further supported by empirical and quantitative research. Rural land use transition of mountainous areas improves natural restoration and is related to socioeconomic development. Rural land consolidation of mountainous areas should conform to land use transition,with the goal of shifting from the increase of cultivated land to the synergies of ecological and environmental protection.张佰林 孙丕苓 姜广辉 张瑞娟 高江波 2019Journal of Geographical Sciences2019,29,10:10
6Topographical relief characteristics and its impact on population and economy:A case study of the mountainous area in western Henan,China显示文摘Topographical relief is a key factor that limits population distribution and economic development in mountainous areas.The limitation is especially apparent in the mountain?plain t「ansition zone.Taking the transition zone between the Qinling Mountains and the North China Plain(i.e.the mountainous area in western Henan Province)as an example and based on the 200-m resolution DEM data,we used the mean change-point analysis to determine the optimal statistical unit for topographical relief,and thereafter extracted the relief degree.Taking the 1:100,000 land use data,township population and county-level industrial data,population and economic spatial models were constructed,and 200?m resolution grid population and economic density maps were gen erated.Afterwards,statistical analysis was carried out to quantitatively reveal the impact of topographical relief on population and economy.In addition,the impacts of other topographical factors were discussed.The results showed the following.(1)The relief degree in western Henan is generally low,where 58.6%of the regional topography does not exceed half the height of a reference mountain(relative elevation W250 m).Spatially,the relief degree is high in the west while low in the east,and high in the middle while low in the north and south.There is a positive correlation between relief degree and elevation,and a much stronger correlation between relief degree and slope.(2)The linear fitting degree between the population and economic validation data and the corresponding simulation data are 0.943 and 0.909,respectively,indicating that the spatialized results can reflect the actual population and economic distribution.(3)The impact of topographical relief on population and economy was stronger than that of other topographical factors.The relief degree showed a good logarithmic fit relati on ship with population density(0.911)and economic density(0.874).Specifically,88.65%of the population lives in areas where the topographical relief is W0.5 and 88.03%of the gross regional product was from areas where the relief is W0.3.Compared with the population distribution,the economic development showed an obvious agglomeration trend towards low relief areas.ZHANG Jingjing ZHU Wenbo ZHU Lianqi CUI Yaoping HE Shasha REN Han 2019Journal of Geographical Sciences2019,29,4:8
7山区生态友好型土地利用对策研究——以重庆市黔江区为例(英文)显示文摘以黔江区为研究对象,通过对生态环境影响因子的分析,发现制约黔江区土地利用环境发展的因素主要有区域气候变化、土壤要素、水文环境以及水土流失和土地退化等。并在以上分析的基础上,进一步分析了土地利用变化对生态环境的影响和制约黔江生态环境及区域发展的因素,最后提出了适应山区土地利用与生态环境协调的对策,对黔江社会经济发展和生态建设具有重要意义。谭伟 张安明 An-ming 2010Agricultural Science & Technology2010,11,5:8
8A COMPUTER MODEL FOR CALCULATING THE DURATION OF SUNSHINE IN MOUNTAINOUS AREAS显示文摘Considering the fact that the sunrise (or sunset) at any point of the mountain is generally not earlier (or later) than that at the horizontal one, the Potential Duration of Sunshine (PDS) at horizontal spot T0 could be divided into n+1 periods, the lengths of the former n periods are all equal to the time interval △T. So n is calculated李占清 翁笃鸣 1988Chinese Science Bulletin1988,33,19:8
9Simulation of hydrological processes of mountainous watersheds in inland river basins: taking the Heihe Mainstream River as an example显示文摘The hydrological processes of mountainous watersheds in inland river basins are complicated.It is absolutely significant to quantify mountainous runoff for social,economic and ecological purposes.This paper takes the mountainous watershed of the Heihe Mainstream River as a study area to simulate the hydrological processes of mountainous watersheds in inland river basins by using the soil and water assessment tool(SWAT)model.SWAT simulation results show that both the Nash–Sutcliffe efficiency and the determination coefficient values of the calibration period(January 1995 to December 2002)and validation period(January 2002 to December 2009)are higher than 0.90,and the percent bias is controlled within±5%,indicating that the simulation results are satisfactory.According to the SWAT performance,we discussed the yearly and monthly variation trends of the mountainous runoff and the runoff components.The results show that from 1996 to 2009,an indistinctive rising trend was observed for the yearly mountainous runoff,which is mainly recharged by lateral flow,and followed by shallow groundwater runoff and surface runoff.The monthly variation demonstrates that the mountainous runoff decreases slightly from May to July,contrary to other months.The mountainous runoff is mainly recharged by shallow groundwater runoff in January,February,and from October to December,by surface runoff in March and April,and by lateral flow from May to September.ZhenLiang YIN HongLang XIAO SongBing ZOU Rui ZHU ZhiXiang LU YongChao LAN YongPing SHEN 2014Journal of Arid Land2014,6,1:7
10Validation and application of water levels derived from Sentinel-3A for the Brahmaputra River显示文摘For the first time ever, this study aims at applying Sentinel-3 A to the Great Brahmaputra River(GBR) and validating water levels derived from this newly-launched altimetry satellite mission. The GBR is divided into three primary parts:(1) a large section of the Yarlung Zangbo River in China, also termed the Upper Brahmaputra River(UBR) in this study, featured by high elevation,complex terrain, narrow river widths(from less than 100 to 400 m), and limited in situ measurements;(2) the Middle Brahmaputra River(MBR) with widths varying from ~400 m to ~1 km;(3) the Lower Brahmaputra River(LBR), dominated by braided channels with wide river channels(up to several kilometers). For the altimetry data, both waveform retracking and hooking effect correction were applied to mitigate the influence caused by land contamination and to improve the accuracy of water level retrievals. Water levels were derived from 41 virtual stations(VSs) across the GBR and different retracking algorithms were compared with in situ data from two gauging stations in the UBR. Time series of altimetry-based water levels were categorized into three types based on the quality: no data(type 1), degraded(type 2), and good(type 3). Results showed that the VSs(type 1) only existed in the mountainous regions, accounting for ~ a half of the total in the UBR. Validation with the gauged water levels showed that the TIC algorithm performed best among all of the retrackers applied, followed by the Ice-1 algorithm. The standard deviation of the difference between the gauged and TIC-derived water levels ranged from 0.41 to 0.76 m among four different VSs(type 3). In addition, the quality of VSs in the LBR was best, followed by the MBR. Our study has demonstrated the capability of Sentinel-3 A in monitoring water levels in the GBR, thereby paving the way for future applications such as discharge estimation and hydrologic/hydrodynamic applications.HUANG Qi LI XingDong HAN PengFei LONG Di ZHAO FanYu HOU AiZhong 2019Science China(Technological Sciences)2019,62,10:6
11Industrial Poverty Alleviation Model in Southwestern High-altitude Mountainous Areas of China——A Case Study of Industrial Poverty Alleviation of Xueshan Township in Luquan County of Yunnan Province through Planting Codonopsis pilosula显示文摘Due to the severe restrictions of natural conditions and ecological environment,high-altitude mountainous areas usually become the ' hard bones' in the battle against poverty. Xueshan Township,Luquan Yi and Miao Autonomous County of Yunnan Province,located in the alpine valley of Jinsha River,is a major township with wide and deep poverty,and the incidence of poverty is up to 45. 00%. In recent years,Xueshan Township has insisted on the battle against poverty,made effort to develop the Codonopsis pilosula industry,and successfully developed a road to poverty alleviation through C. pilosula industry,and formed a unique industrial poverty alleviation model by the end of 2018,the incidence of poverty dropped to 0. 74%. Based on field survey and interview,this paper analyzes and summarizes the specific practices,main results,practical experience and promotion and application measures of the poverty alleviation model of C. pilosula planting industry in Xueshan Township,in the hope of providing certain reference for the targeted poverty alleviation in similar areas in Yunnan Province and other provinces of China.Zisheng YANG Renyi YANG Yanbo HE Chonghui LU En ZHU Yaohan PI Mingxin WU Ying XIONG 2019Asian Agricultural Research2019,11,3:4
12The mechanism of farmland marginalization in Chinese mountainous areas:Evidence from cost and return changes显示文摘Farmland marginalization has become the main trend of Iand-use change in the mountainous areas of China.Using annual survey data of major agricultural production costs and earnings at national and provincial levels in China,this study aims to analyze the reasons and mechanism behind farmland marginalization in mountainous areas.We find that farmers on plains are able to reduce their per mu labor input effectively through in tensive use of agricultural machinery,which has minimized the impact of the increase in labor price.However,it is extremely challenging for farmers in mountainous areas to use the same method owing to the rough terrain.Thus,per laborer farming area in these areas has increased relatively slowly,causing a widening gap in agricultural labor productivity between the two regions.With the rapid rise in labor costs since 2003,the marginalization of cultivated land in mountainous areas is evident.In 2013,the net profit of agricultural production in mountainous China fell below zero.Since 2000,the Iand-use and land?cover change in these areas was characterized by the reduction of farmland area,reforestation,and the enhancement of the NDVI value.The high correlation between the NDVI change rate and the ratio of change in farmland(r=-0.70)and forest(r=0.91)in mountainous areas at provincial level further attests to the trend of farmla nd margi nalization there.Fin ally,we summarize the mecha nism of such marginalization against the backdrop of the rapid increase in the opport unity cost of farming and the rapid fall of agricultural labor forces in mountainous areas.This study contributes to a deep understanding of the development process of farmland marginalization and abandonment as well as forest transition in Chinese mountainous areas.LI Shengfa LI Xiubin 2019Journal of Geographical Sciences2019,29,4:4
13Snowmelt modeling using two melt-rate models in the Urumqi River watershed, Xinjiang Uyghur Autonomous Region, China显示文摘In this paper,the performance of the classic snowmelt runoff model(SRM)is evaluated in a daily discharge simulation with two different melt models,the empirical temperature-index melt model and the energy-based radiation melt model,through a case study from the data-sparse mountainous watershed of the Urumqi River basin in Xinjiang Uyghur Autonomous Region of China.The classic SRM,which uses the empirical temperature-index method,and a radiation-based SRM,incorporating shortwave solar radiation and snow albedo,were developed to simulate daily runoff for the spring and summer snowmelt seasons from 2005 to 2012,respectively.Daily meteorological and hydrological data were collected from three stations located in the watershed.Snow cover area(SCA)was extracted from satellite images.Solar radiation inputs were estimated based on a digital elevation model(DEM).The results showed that the overall accuracy of the classic SRM and radiation-based SRM for simulating snowmeltdischarge was relatively high.The classic SRM outperformed the radiation-based SRM due to the robust performance of the temperature-index model in the watershed snowmelt computation.No significant improvement was achieved by employing solar radiation and snow albedo in the snowmelt runoff simulation due to the inclusion of solar radiation as a temperature-dependent energy source and the local pattern of snowmelt behavior throughout the melting season.Our results suggest that the classic SRM simulates daily runoff with favorable accuracy and that the performance of the radiation-based SRM needs to be further improved by more ground-measured data for snowmelt energy input.Muattar SAYDI DING Jian-li Vasit SAGAN QIN Yan 2019Journal of Mountain Science2019,16,10:3
14Study on Landscape Features of Bai People'sTraditional Mountainous Villages in Dali显示文摘In view of the vast mountainous areas and abundant mountainous settlement resources of Dali Bai Nationality Autonomous Prefecture, the authors proposed the significance and necessity of studying landscape features of traditional mountainous settlements of the Bai Nationality by considering policy requirements of 'protection system planning of famous historic and cultural cities, towns, villages and blocks in Yunnan Province' and 'construction of mountainous towns'. On the basis of investigating traditional mountainous settlements of the Bai Nationality in Dali, 5 typical settlements were analyzed from the perspectives of landscape structure, village layout, landscape element, landscape materials and decorative art. And characteristics of traditional mountainous settlements of the Bai Nationality were summarized as 'following the nature, adaptive to actual terrains, multidimensional, human-nature oneness'.BAO Rong WANG Dong DU Chunyan 2013Journal of Landscape Research2013,5,Z1:3
15Dynamic hydraulic jump and retrograde sedimentation in an open channel induced by sediment supply: experimental study and SPH simulation显示文摘Mountainous torrents often carry large amounts of loose materials into the rivers, thus causing strong sediment transport. Experimentally it was found for the first time that when the intensive sediment motion occurs downstream over a gentle slope, the siltation of the riverbed is induced and the sediment particles can move upstream rapidly in the form of a retrograde sand wave, resulting in a higher water level along the river. To further study the complex mechanisms of this problem, a sediment mass model in the framework of the Smoothed Particle Hydrodynamics(SPH) method was presented to simulate the riverbed evolution, sediment particle motion, and the generation and development of dynamic hydraulic jump under the condition of sufficient sediment supply over a steep slope with varying angles. Because the sediment is not a continuous medium, the marker particle tracking approach was proposed to represent a piece of sediment with a marked sediment particle. The twophase SPH model realizes the interaction between the sediment and fluid by moving the bed boundary particles up and down, so it can reasonably treat the fluid-sediment interfaces with high CPU efficiency. The critical triggering condition of sediment motion, the propagation of the hydraulic jump and the initial siltation position were all systematically studied. The experimental and numerical results revealed the extra disastrous sediment effect in a mountainous flood. The findings will be useful references to the disaster prevention and mitigation in mountainous rivers.ZHENG Xiao-gang CHEN Ri-dong LUO Min KAZEMI Ehsan LIU Xing-nian 2019Journal of Mountain Science2019,16,8:2
16华北山地传统聚落中的街道空间(英文)显示文摘With mountainous area of North China as the research objective,the study analyzed street space in traditional settlements in mountainous area of North China from the perspective of form,structure and culture,hoping to find some methods and laws that could be served as the reference for the design of living environment in future.彭鹏 刘丽 2010Journal of Landscape Research2010,2,11:2
17以山地景观为特征的观光农业园规划设计(英文)显示文摘After illustration of research and development process of sightseeing agricultural park,the paper had classified sightseeing agricultural park into sightseeing agricultural park,education agricultural park and agricultural garden in terms of development content;into renovation type and newly-built type in accordance with development mode;and into plain type and mountainous type in the light of terrain.From the perspectives of terrain,vegetation,hydrology and ecology,characteristics of landscape resources in mountainous sightseeing agricultural park were analyzed.It proposed principles for planning and design of mountainous sightseeing agricultural park,which were respecting and protecting nature,linking landscape units and coordinating spatial structure,systematicness and protecting inheritance of traditional culture.On this basis,it had illustrated landscape designing theories on architecture and landscape furniture,traffic road,plant greening and water supply and sewerage works.杨金娥 张建林 2011Journal of Landscape Research2011,3,4:2
18Status of Impoverished Population and Contradiction of Economic Development in Qinling-Bashan Mountainous Area——A Case Study of Hanzhong City,Shaanxi Province显示文摘The status of impoverished population and economic development in Qinling-Bashan Mountainous area,Shaanxi is introduced based on the brief account of its general situation.Firstly,there are a large proportion of rural people and great outflow of population;a considerable proportion of the weak,the disabled,the sick and the dementia and low population quality;weak capacity of the economy to generate profit on its own and declining trend of financial self-sufficiency rate.taking into account that Qinling-Bashan Mountainous area is the poorest area with the largest impoverished population and the most complex structure of poverty,the impact of the status of the poor population in Qinling-Bashan Mountainous area on its economy is discussed:the first one is backward ecological concept and serious damage to ecological environment;outflow of excellent talents and a serious shortage of labor;the industrial structure is irrational and the resources advantage can not be transformed into economic advantage.Some corresponding measures and suggestions are proposed:the first one to build new small town so as to lessen the loss of population;the second one is to provide preferential policies so as to attract and retain qualified person;the third one to develop education and establish the concept of ecological civilization;the fourth one is to unblock the channels of information transmission and restructure the industry.MA Zheng-jie Shaanxi University of Technology,Hanzhong 723001,China 2010Asian Agricultural Research2010,2,3:2
19生态旅游:乌蒙山区生态修复与脱贫发展新思路(英文)显示文摘The economic and social development status and the formation mechanism of 'poverty trap' in Wumeng mountainous area were analyzed, the feasibility of developing eco-tourism to ecological restoration and rural poverty reduction was discussed, and some corresponding countermeasures were put forward.张绪清 2010Journal of Landscape Research2010,2,4:2
20Spatial pattern and driving factors of biomass carbon density for natural and planted coniferous forests in mountainous terrain,eastern Loess Plateau of China显示文摘Background:Understanding the spatial pattern and driving factors of forest carbon density in mountainous terrain is of great importance for monitoring forest carbon in support of sustainable forest management for mitigating climate change.Methods:We collected the forest inventory data in 2015 in Shanxi Province,eastern Loess Plateau of China,to explore the spatial pattern and driving factors of biomass carbon density(BCD)for natural and planted coniferous forests using Anselin Local Moran’s I,Local Getis-Ord G*and semivariogram analyses,and multi-group structural equation modeling,respectively.Results:The result of spatial pattern of BCDs for natural forests showed that the BCD was generally higher in the north but lower in the south of Shanxi.The spatial pattern for planted forests was substantially different from that for natural forests.The results of multi-group SEM suggested that elevation(or temperature as the alternative factor of elevation)and stand age were important driving factors of BCD for these two forest types.Compared with other factors,the effects of latitude and elevation on BCD showed much greater difference between these two forest types.The difference in indirect effect of latitude(mainly through affecting elevation and stand age)between natural and planted forests was to some extent a reflection of the difference between the spatial patterns of BCDs for natural and planted forests in Shanxi.Conclusions:The natural coniferous forests had a higher biomass carbon density,a stronger spatial dependency of biomass carbon density relative to planted coniferous forests in Shanxi.Elevation was the most important driving factor,and the effect on biomass carbon density was stronger for natural than planted coniferous forests.Besides,latitude presented only indirect effect on it for the two forest types.Lina Sun Mengben Wang Xiaohui Fan 2020Forest Ecosystems2020,7,1:2
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