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1.
The Beautiful China Initiative(BCI)is a plan for the sustainable development of the Chinese nation as well as for China to fulfill the United Nations’2030 Agenda for Sustainable Development.The Chinese government’s“five-in-one”approach provides strategic arrangements for developing the BCI,and President Xi Jinping proposed a timetable and“road map”for the BCI at the National Conference on Ecological and Environmental Protection.Nevertheless,the theoretical basis,evaluation index system,evaluation criteria and effectiveness of the BCI are currently unclear.This paper begins by exploring the basic content of the BCI from narrow and broad perspectives.It regards the theory of human-nature harmonious coexistence and the five-in-one beauty theory as the core theoretical bases of the BCI and constructs a five-element BCI evaluation index system(ecological environment,green development,social harmony,system perfection and cultural heritage)and utilizes the assessment method of the United Nations’Human Development Index to assess scientifically the effectiveness of the BCI in 341 prefecture-level cities.The results show the average BCI index(the Chinese Academy of Sciences Beauty Index)score to be 0.28,which is quite low,while the average scores for the individual element indexes of the ecological environment index,green development index,social harmony index,system perfection index and cultural heritage index are 0.6,0.22,0.29,0.22 and 0.07,respectively.All of these are relatively low values,with relatively large discrepancies in regional development,indicating that progress in the BCI is generally slow and unbalanced.To realize the BCI’s timetable and roadmap to a high quality and high standard,it is suggested that a common system for evaluating the progress of the BCI is developed and promulgated so that dynamic monitoring and phased evaluations can take place;BCI technical assessment standards are compiled and published;BCI comprehensive zoning is undertaken;pilot projects adapted to local conditions are launched in BCI sample areas;and BCI results are incorporated into performance indicators at all levels of government.  相似文献   

2.
With basic information from 8353 archaeological sites, this study describes a holistic spatial-temporal distribution pattern of archaeological sites of the prehistoric culture sequence from 9.5 ka BP (ka BP = thousands of years before 0 BP, where "0 BP" is defined as the year AD 1950) to 2.3 ka BP in the region that extends from the Yanshan Mountains to the Liaohe River Plain(i.e., the Yan-Liao region) in northern China. Based on spatial statistics analysis – including the spatial density of the sites and Geographic Information System nearest-neighbour analysis, combined with a review of environmental and climatic data – this paper analyses cultural evolution, the spatial-temporal features of the archaeological sites and human activities against the backdrop of climatic and environmental changes in this region. The results reveal that prehistoric cultural evolution in the Yan-Liao region is extensively influenced by climatic and environmental changes. The Xinglongwa, Zhaobaogou and Fuhe cultures, which primarily developed during a habitable period from 8.5 ka BP to 6.0 ka BP with strong summer monsoons, have similar maximum density values, spatial patterns and subsistence strategies dominated by hunting-gathering. Significant changes occurred in the Hongshan and Lower Xiajiadian cultures, with a significant increase in numbers and densities of sites and a slump in average nearest-neighbour ratio when the environment began to deteriorate starting in 6.0 ka BP. Additionally, with the onset of a weak summer monsoon and the predominance of primitive agriculture, sites of these two cultures present a different type of concentric circle-shaped pattern in space. As the environment continuously deteriorated with increasing aridity and the spread of steppe, more sites were distributed towards the south, and primitive agriculture was replaced by livestock husbandry in the Upper Xiajiadian culture. The most densely populated areas of the studied cultures are centralized within a limited area. The Laohahe River and Jiaolaihe River basins formed the core area in which most archaeological sites were distributed during the strong summer monsoon period and the first few thousand years of the weak summer monsoon period.  相似文献   

3.
Protected areas have a double mandate of both "protection" and "use." Naturebased tourism is considered an effective tool in terms of environmental conservation. Understanding the causes and consequences of a spatiotemporal succession of tourism construction is an important channel to explore the changes of tourism-environment interaction in the protected area. To analyze the spatio-temporal variations in tourism construction lands, we adopted Mt. Bogda as an example. We systematically quantified the interaction between these changes and environmental variables and explored the evolution process of tourism-environment interaction of the mountainous protected area in the northwest arid region. Our results revealed the following:(1) In the Bogda protected area, the proportion of tourism construction lands first appeared to be increasing, then decreasing dramatically, and finally growing slowly. The spatial expansion of tourism construction lands followed the "core-periphery" pattern, respectively showing shapely infilling, reasonable agglomeration, barycenter shift, and outlying growth from 1990 to 2018 as the stages of concentrating on the core.(2) The higher land-use intensity of tourism construction drove the changes of landscape fragmentation, diversity, stability, primitive, and nature degree in the protected area. The coupling coordination between tourism and the environment in the Bogda area decreased at first, and then slowly increased. Meanwhile, tourism did not cause irreversible damage to the natural environment, and the coupling coordination degree between tourism and the environment was still in the state of balanced development. It expressed the states of original balanced, development exceeds environment and barely balanced, and superiorly balanced. The historical evolution of tourism-environment interaction in Bogda reflects the pattern of periodic changes in China’s protected areas to a certain extent.  相似文献   

4.
Based on the measured discharge,sediment load,and cross-sectional data from 1986 to 2015 for the lower Yellow River,changes in the morphological parameters(width,depth,and cross-sectional geomorphic coefficient)of the main channel are analyzed in this paper.The results show that before the operation of the Xiaolangdi Reservoir(XLDR)from 1986 to 1999,the main channel shrunk continually,with decreasing width and depth.The rate of reduction in its width decreased along the river whereas that of depth increased in the downstream direction.Because the rate of decrease in the width of the main channel was greater than that in channel depth,the cross-sectional geomorphic coefficient decreased in the sub-reach above Gaocun.By contrast,for the sub-reach below Gaocun,the rate of decrease in channel width was smaller than that in channel depth,and the cross-sectional geomorphic coefficient increased.Once the XLDR had begun operation,the main channel eroded continually,and both its width and depth increased from 2000 to 2015.The rate of increase in channel width decreased in the longitudinal direction,and the depth of the main channel in all sub-reaches increased by more than 2 m.Because the rate of increase in the depth of the main channel was clearly larger than that of its width,the cross-sectional geomorphic coefficient decreased in all sub-reaches.The cross-sectional geometry of the main-channel of the lower Yellow River exhibited different adjustment patterns before and after the XLDR began operation.Before its operation,the main channel mainly narrowed in the transverse direction and silted in the vertical direction in the sub-reach above Aishan;in the sub-reach below Aishan,it primarily silted in the vertical direction.After the XLDR began operation,the main channel adjusted by widening in the transverse direction and deepening in the vertical direction in the sub-reach above Aishan;in the sub-reach below it,the main channel adjusted mainly by deepening in the vertical direction.Compared with the rates of decrease in the width and depth of the main channel during the siltation period,the rate of increase in channel width during the scouring period was clearly smaller while the rate of increase in channel depth was larger.After continual siltation and scouring from 1986 to 2015,the cross-sectional geometry of the main-channel changed from wide and shallow to relatively narrow and deep.The pattern of adjustment in the main channel was closely related to the water and sediment conditions.For the braided reach,the cross-sectional geomorphic coefficient was negatively correlated with discharge and positively correlated with suspended sediment concentration(SSC)during the siltation period.By contrast,the cross-sectional geomorphic coefficient was positively correlated with discharge and negatively correlated with SSC during the scouring period.For the transitional and meandering reaches,the cross-sectional geomorphic coefficient was negatively correlated with discharge and positively correlated with SSC.  相似文献   

5.
The town of Agura,a typical region in Horqin Sandy Land,was selected as the study area in this paper.Using 12 remote sensing images and climatic data from the past 20 years,the effects of climate change on surface environments were analyzed.The impact indices of climatic factors,along with their corresponding ranks,were used to characterize the responses of different types of surface environments to climate change.Results show that in the past 20 years,the surface environments of the study area have been deteriorating.Furthermore,there is a positive relationship between the changes in surface environments and those in climatic factors.Various climatic factors influence surface environments in different ways and at different levels.The most sensitive factor is relative humidity,followed by precipitation and evaporation.Overall,moisture is the key factor that affects the changes in surface environments of arid and semi-arid areas.  相似文献   

6.
今年是广东省建成北回归线标志25周年。2011-06-22台湾嘉义、广东汕头、从化、封开、广西桂平、云南墨江等海峡两岸6座北回归线标志所在市、县,举行联动观测夏至正午太阳直射的大型活动,华南师范大学地理科学学院刘南威教授在活动筹办期间接受记者采访,畅谈广东地理学界对北回归线标志兴建的主要贡献和海峡两岸联动观测正午太阳直射活动的重要意义。  相似文献   

7.
名吃路一路名吃名吃路一路名店名吃路一路名牌四川成都被誉为美食之都,成都市的春熙路被誉为美食之都的夜总汇。春熙路位于成都市中心,包括东大街以北,南新街、中新街、北新街以东,总府路以南,红星路以西的范围及临街区域,面积约20公顷。春熙路是一条历史悠久、繁华的商业街,是成  相似文献   

8.
The shapes of the urban lakes in Wuhan city have been strongly influenced by the rapid industrialization and urbanization experienced in recent decades.Based on topographic maps and remote sensing images,the temporal and spatial changes of East Lake,Wuhan city,over the past two decades were analyzed.The landscape shape index(LSI)and centroid method were applied to analyze the evolution of lake morphology and its causes.Several key results were obtained.(1)The surface area of East Lake decreased sharply by 2.13 km2 from 1995 to 2005,and slightly by 1.00 km2 from 2005 to 2015.The shoreline length of East Lake displayed a continuous trend of decline during the study period:The length reduced by 21.89 km from 1995 to 2005,and by 0.67 km from 2005 to 2015.The LSI values,7.04(1995),6.46(2005),and 6.28(2015),displayed an accelerated downward trend,indicating a reduction of complexity in East Lake and the intensification of manual interventions in the water body.(2)The changes to East Lake displayed a clear temporal and spatial heterogeneity.The centroid of East Lake moved northeast from 1995 to 2005 and southeast from 2005 to 2015.(3)The reduction in the area of East Lake was mainly affected by human activities.A lake area of about 4.8 km2 was converted to other land uses during 1995-2005,most of which was unused land,whereas from 2005 to 2015,0.43 km2 of the lake area was converted into built-up land,and 0.25 km2 was converted into other land uses.The reduction in area was caused by infrastructure construction by the government,the development of the real estate industry,illegal construction by villagers,and the development of scenic spots for tourism.The driving forces of this reduction included Wuhan's growing population,and the rapid development of the economy and urbanization between 1995 and 2015,which has resulted in a large demand for land.Finally,a formation mechanism model was constructed by analyzing the causes of East Lake's morphological evolution.  相似文献   

9.
Ground temperatures from four of the seven extensively studied highway cross-sections near Gulkana/Glennallen,Alaska during 1954~1962,were chosen to better understand the impacts of highway construction on warm permafrost.Both the thawing of permafrost and seasonal frost action impacted on road surface stability for about 6 years until the maximum summer thaw reached about 3 m in depth.Seasonal frost action caused most of the ensuing stability problems.Unusually warm summers and the lengths of time required to re-freeze the active layer were far more important than the average annual air temperatures in determining the temperatures of the underlying shallow permafrost,or the development of taliks.The hypothesized climate warming would slightly and gradually deepen the active layer and the developed under-lying talik,but its effect would be obscured by unusually warm summers,by warmer than usual winters,and by the vari-able lengths of time of the zero curtains.At least one period of climate mini-cooling in the deeper permafrost during the early 20th century was noted.  相似文献   

10.
董巨峰 《地理学报》2008,63(1):109-109
"干旱、半干旱区环境演变与可持续发展国际学术讨论会"(International Workshop on Environmental Changes and Sustainable Development in Arid and Semi-arid Regions)于2007年9月10-14日在内蒙古自治区阿拉善左旗成功举办.会议由国际地貌学家协会(IAG)、国际地理联合会荒漠化与土地退化委员会(COMLAND)、中国第四纪研究会、中国地理学会等学术团体发起,国家自然科学基金、PAGES及中国科学院资助,中国科学院地质与地球物理研究所主办,内蒙古阿拉善盟行署、南京大学协办.  相似文献   

11.
Palaeoflood hydrological study is a frontal subject of global change study. Using sedimentology, geomorphology and OSL dating methods, the typical palaeoflood slackwater deposits were studied in the Qishuihe River valley. The results showed that five flooding episodes with 21 palaeoflood events occurred during 4300–4250 a B.P., 4250–4190 a B.P., 4190–4100 a B.P., 4100–4000 a B.P. and 3100–3010 a B.P., respectively, during the Holocene period. The palaeoflood peak discharges were calculated with hydrological models. With a combination of the gauged flood, historical flood and palaeoflood hydrological data, the archives of flood events were extended to over 10,000 years in the Qishuihe River valley, and the flood frequency–peak discharge relationship curve was established accurately. These research results played important roles in mitigating flood hazard, hydraulic engineering and also the development of water resources in the semiarid Weihe River basin.  相似文献   

12.
关中西部漆水河全新世特大洪水与环境演变   总被引:14,自引:6,他引:14  
古洪水水文学研究是全球变化研究的前沿课题。本文通过对漆水河流域深入调查研究, 在漆水河与湋河交汇的二级阶地全新世黄土-土壤剖面中发现古洪水沉积夹层, 利用沉积地貌学、沉积学、考古学和释光年代学方法, 确定了在全新世时期的11500 年内, 漆水河曾经在4650~4600a BP、4600~4300a BP、4300~4100a BP 和3100~3000a BP 发生了4 期20 次洪水事件。通过利用水位-流量关系模型, 计算出这4 期20 次特大洪水的洪峰流量, 大大延长了洪水水文数据序列, 并建立了漆水河全新世洪水频率曲线, 科学、系统地提高了漆水河洪水水文学计算精度, 增强了渭河流域防洪减灾和水资源开发当中洪水频率分析的可靠性。这项研究成果对于我国著名的农业科技城-杨凌的防洪减灾、水资源开发和生态环境建设具有重要的应用价值, 同时填补了渭河流域古洪水水文学研究的空白, 对于渭河流域生态环境综合治理具有重要的科学意义。  相似文献   

13.
泾河中游全新世古洪水沉积学与水文学研究(英文)   总被引:1,自引:1,他引:0  
Palaeo-hydrological field investigation was carried out in the middle reaches of the Jinghe River. A set of palaeoflood slackwater deposit beds was identified in the Holocene loess-soil sequence in the riverbanks. The sediment samples were collected from the profile, and the particle-size distribution, magnetic susceptibility, loss-on-ignition were analyzed in laboratory. The analytical results showed that the palaeoflood slackwater deposits have re-corded extraordinary flood events in the Jinghe River valley. According to stratigraphic cor-relation and OSL dating, the palaeoflood events were dated to 4100-4000 a BP. The pa-laeoflood peak discharges were estimated to be 19,410-22,280 m3/s by using the hydro-logical model and checked by different approaches. These results have the flood data se-quence of the Jinghe River extended to 10,000-year time-scale. It provided significant data for hydraulic engineering and for mitigation of flood hazards in the Jinghe River drainage basin.  相似文献   

14.
总结近年来在汉江上游古洪水研究成果的基础之上,采用文献资料分析和洪水模拟计算方法,对汉江上游6个沉积剖面纪录的东汉时期古洪水事件进行了年代考证和洪水模拟计算。结果表明,通过分析文献记载的汉江上游东汉时期洪水影响范围、强度和程度,以及结合洪痕沉积规律,在时间上考证认为这6个沉积剖面记录的东汉时期古洪水事件可能是东汉建安二年(197年)九月的一次特大洪水事件。选取合适的河槽横断面和糙率系数,采用HEC-RAS模型对距离较近的4个沉积面记录的东汉时期古洪水事件进行洪水模拟计算,模拟洪水位与各剖面依据古洪水SWD恢复的洪水位误差在-0.18%~0.25%,而且模拟的1983年洪水位与剖面及其附近发现的1983年洪痕水位误差小于0.25%,说明洪水模拟计算选取的河槽横断面和水文参数准确、可靠,从洪水模拟计算的角度也说明了汉江上游沉积记录的东汉时期古洪水事件可能为一次特大洪水事件。该研究结果不仅延长了汉江上游洪水序列,而且也为汉江上游水利工程建设、水资源管理和防洪减灾等提供重要的水文资料。  相似文献   

15.
通过对黄河上游洮河流域详细的野外考察,在临洮段下堡村(XBC)发现保存有全新世古洪水滞流沉积物的地层剖面并对该剖面进行系统采样,综合野外观测和室内理化数据分析确定为古洪水滞流沉积物。结合全新世地层对比、文化遗物分析和释光测年,确定这期古洪水事件发生在300~480 a BP左右,相当于我国"明清小冰期"气候转折阶段。利用ArcGIS耦合HEC-RAS模型,在获取河道水文参数条件下,恢复其洪峰流量介于4 865~6 700 m3·s-1。保持水文参数不变,对河道糙率系数进行灵敏度测试,给定糙率±25%的变幅,结果误差在-9.12%~6.57%之间。依据2012年洪痕高程,采用HEC-RAS模型恢复其洪峰流量,与实测结果相比较误差仅为-2.9%,说明利用该模型得出的结果是比较可靠的。该研究成果有效延长了黄河上游洪水数据序列,这对于该流域内防洪减灾、水利工程建设和水资源开发利用等具有重要的参考价值。  相似文献   

16.
通过深入的野外考察,在汉江上游郧县五峰段多个地点发现全新世古洪水事件的沉积学记录,为恢复史前特大洪水事件的洪峰水位和洪峰流量提供了物质基础。在系统获取河道水文参数的基础上,采用ArcGIS 耦合HEC-RAS模型,推算出其洪峰流量介于42 220~63 400m3/s 之间。对于河槽糙率的灵敏度检验表明,给定糙率变化±25%,模型模拟得到的洪峰流量误差在-10.6%~6.3%之间。这个误差范围远小于采用比降-面积法获得的结果。同时,采用该模型和同样的参数,依据该河段现代大洪水洪痕高程,恢复推算其洪峰流量,其结果与实测数据误差在-3.9%~1.0%之间。与其它方法相比较,这种新方法有效地提高了水文参数选取准确性,使得古洪水水文恢复计算结果更为可靠。本研究为超长尺度大洪水水文学恢复提供了新的途径,也获得了汉江上游万年尺度特大洪水的水文学数据资料,对汉江上游水利水电枢纽工程建设、水资源调度和防洪减灾具有重要的现实意义。  相似文献   

17.
通过野外观察研究,在黄河中游晋陕峡谷永和县佛堂村(FTC)支沟口的回水湾内发现了全新世古洪水滞流沉积物。结合沉积学分析,判定它们是典型的全新世古洪水悬移质泥砂颗粒在高水位滞流环境中的沉积物。利用“古洪水SWD厚度含沙量法”恢复古洪水洪峰水位,借助HEC-RAS模型估算出4次古洪水事件洪峰流量在25 200~51 500 m3·s-1之间。OSL测年结果显示,FTC地点的古洪水发生在1 900~1 700 a BP、3 400~3 000 a BP。全新世气候变化研究表明,这两个时期气候恶化,旱涝灾害多有发生。FTC地点的两期四次洪水反映了这两个时期的气候异常变化成果,表明了黄河中游水文系统对气候变化作出的响应,也印证了季风区河流对气候突变的响应规律,为黄河中下游地区防洪减灾和水资源开发提供了基础数据。  相似文献   

18.
汉江上游白河段万年尺度洪水水文学研究   总被引:3,自引:0,他引:3  
通过对汉江上游的考察,在多个地点发现古洪水滞流沉积层夹在古土壤层与坡积石渣土层或坡积角砾层中。选择白河段JJTZ剖面进行沉积学和水文学研究。对于采集的全新世古洪水滞流沉积样品,进行沉积学分析,与2010年现代洪水滞流沉积物进行对比,结合其宏观特征确认其为汉江洪水悬移质沉积物,粒度成分分类为细沙质粉沙。它们记录了汉江上游特大古洪水事件。通过地层学对比分析和OSL测年断代,确定其发生在全新世中期-晚期转折阶段,即3 200~2 800 a B.P.。利用沉积学和古水文学原理恢复古洪水洪峰水位,采用比降法计算出两次古洪水洪峰流量为40 180 m3/s和49 170 m3/s。该结果大大延长了洪水水文数据序列,从而能够建立汉江上游万年尺度洪水流量-频率关系,对于揭示汉江上游水文过程对于全球变化的响应规律具有重要的科学意义,对于防洪减灾和水资源水能源工程建设具有重要的现实意义。  相似文献   

19.
Palaeoflood hydrology study is a leading subject in global change study. Through field investigation in the upper reaches of Hanjiang River, palaeoflood slackwater deposits (SWD) were found in the bedrock gorges of the Yunxi reach. The results of field observation, laboratory analysis including particle-size distribution and magnetic susceptibility, and comparison with modern flood deposits, the SWD were identified as the most typical Holocene palaeoflood deposits of the Hanjiang River. By using stratigraphic correlation and OSL dating method, the palaeoflood event was dated to be 3200-2800 a BP at the turn from the middle to late Holocene. According to the palaeoflood peak stage and hydraulic parameters, the peak discharges of the palaeoflood were reconstructed as 48,830-51,710 m3/s by using the slope-area method. At same time, the flood peak discharges of 1983, 2005 and 2010 severe floods were reconstructed with the same method and hydraulic parameters in the same cross section. The error between the reconstructed and gauged discharges was 1.99%-4.21%. This showed that the reconstructed palaeoflood peak discharges were reliable. The flood peak discharge-frequency relationship at 10,000-year time scale was established by a combination of the gauged flood, historical flood and palaeoflood hydrological data. These results are very important for hydraulic engineering and flood mitigation on the Hanjiang River.  相似文献   

20.
通过对汉江上游河谷的考察, 在旬阳县东段构元-棕溪乡河段发现的典型的全新世古洪水滞流沉积剖面, 进行了古洪水沉积学和水文学研究。在野外考察的基础上, 对于采集的全新世地层剖面序列样品, 进行粒度成分和磁化率等分析测试, 从沉积角度揭示了这些沉积层是古洪水在高水位滞流环境中悬移质泥沙的沉积物。通过地层对比分析确定由其记录的古洪水事件分别发生全新世早期9000~8500 a B.P.和全新世晚期3200~2800 aB.P.。利用古水文学原理恢复其洪峰水位, 计算出古洪水洪峰流量介于45630~50220 m3/s 之间。结合现代洪水洪痕洪峰计算、洪峰流量与流域面积关系分析多种方法, 对古洪水洪峰流量计算结果进行了验证, 从而建立了更加可靠的万年尺度洪峰流量与频率关系。本文的研究成果, 对汉江上游水资源开发、防洪减灾、水土保持和深入理解汉江上游水文过程对全球变化的响应规律具有重要的科学意义。  相似文献   

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