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11.
关于确保甘肃省祁连山生态保护红线落地并严守的科技支撑建议 总被引:1,自引:0,他引:1
祁连山是中国西部重要生态安全屏障,是国家重点生态功能区,其生态保护与治理一直受到国家、地方政府和当地居民高度关注。目前,在祁连山的生态保护工作中,缺乏对现状基础数据的全面掌握,区域经济发展与生态环境保护矛盾突出,生态环境综合监测系统不完备,生态补偿机制推进实施缺乏创新。在全面梳理祁连山目前存在的重大生态问题的基础上,提出了祁连山生态保护红线落地并严守的建议,包括加快开展祁连山综合科学考察、完善并落实开展生态补偿机制、探索以正面清单为导向的协调发展模式、促进生态安全与地方经济社会可持续发展相协调、进一步实施重大配套政策、完善保障支撑体系等。 相似文献
12.
A comprehensive analysis of phenological changes in forest vegetation of the Funiu Mountains,China 总被引:1,自引:2,他引:1
Journal of Geographical Sciences - This paper reports the phenological response of forest vegetation to climate change (changes in temperature and precipitation) based on Moderate Resolution... 相似文献
13.
Characteristic of Gravity and Magnetic Anomalies in the Daba Shan and the Sichuan basin, China: Implication for Architecture of the Daba Shan 总被引:2,自引:0,他引:2
The Dabashan nappe structural belt links the Hannan block to the west with the Huangling block to the east between Yangxian and Xiangfan. The Dabashan arc-shaped fold belt formed during late Jurassic and was superposed on earlier Triassic folds. To achieve an improved understanding of the deep tectonics of the Dabashan nappe structural belt, we processed and interpreted the gravity and magnetic data for this area using new deep reflection seismic and other geophysical data as constraints. The results show that the Sichuan basin and Daba Mountains lie between the Longmenshan and Wulingshan gravity gradient belts. The positive magnetic anomalies around Nanchong-Tongjiang-Wanyuan-Langao and around Shizhu result from the crystalline basement. Modeling of the gravity and magnetic anomalies in the Daba Mountains and the Sichuan basin shows that the crystalline basement around Nanchong-Tongjiang-Wanyuan-Langao extends to the northeast underneath the Wafangdian fault near Ziyang. The magnetic field boundary in the Zhenba-Wanyuan-Chengkou-Zhenping area is the major boundary of the Dabashan nappe thrusting above the Sichuan Basin. This boundary might be the demarcation between the south Dabashan and the north Dabashan structural elements. The low gravity anomaly between Tongjiang and Chengkou might be partly caused by thickened lower crust. The local low gravity anomaly to the south of Chengkou-Wanyuan might result from Mesozoic strata of low density in the Dabashan foreland depression area. 相似文献
14.
中国扶贫瞄准单位已下沉到农户单元,发展和完善农户尺度的多维贫困测度方法是精准配置扶贫资源、提高扶贫效率的关键。通过借鉴“人”“地”和“业”关系理论构建了“能力—资本—环境”多维贫困综合评估框架,以秦巴山特困区商洛为例,通过多维贫困测度体系对农户进行综合测度,识别样本区多维贫困户,进而与建档立卡贫困户进行对比分析,并探讨了多维贫困发生的主要影响机理,最后依据多维贫困户剥夺维度的组合划分不同类型。研究结果表明:① 有245户被识别为多维贫困户,239户被识别为非多维贫困户,多维贫困户与非多维贫困户在能力维度、资本维度和环境维度均存在较大差异;② 有84.08%的多维贫困户与建档立卡贫困户相重叠,多维贫困户在综合维度和单维度的贫困程度均较深;③ 多维贫困发生主要受“人”的发展能力和生产能力、“业”的金融资本、物质资本以及“地”的地理条件和区位的弱势或剥夺的影响;④ 多维贫困户划分为发展缺失型、复合贫困型、生存环境恶劣型和综合贫困型4类。 相似文献
15.
A study on environmental aridity over northern and southern to Qinling Mountains under climate warming 总被引:6,自引:0,他引:6
1 Introduction With progressive researches on global climate change, an integrated study of various disciplines tends to be inevitable. Mr. Moore III, chairman of IGBP, holds that the key to integration is to synthesize scientific findings so as to get new ideas and to chance cognition up to a new high[1]. Micro-study, rather than macro-study focuses on regional change[2-5]. To strengthen the global perspective in the study, "to research on typical regions and to deepen the regional divide… 相似文献
16.
17.
Arthur E. Bettis III 《自然地理学》2013,34(3):263-279
Inceptisols are developed on silt loam, loam, and sandy loam Indian mounds at the Keller Mound Group and Bluff Top Mound in northeastern Iowa. The mounds date to the Allamakee Phase of the Late Woodland Period (ca. 1650–1250 B.P.) and are built with fill obtained from the A, E, and upper B horizons of pre-existing soils (Alfisols). Differences in the morphologic and chemical characteristics of soils on different mounds are attributed to textural differences of the mounds' fill. Coarse-textured mound fill is pedogenically altered at a faster rate than fine-textured fill, but total carbon percentage of the A horizon attains a steady state faster in fine-textured mound fill. Total phosphorus content is used to determine from which horizons of pre-existing soils the specific layers of mound fill originated. Rates and pathways of pedogenesis in mound fill may not provide good analogues for the early stages of soil development in materials that have not undergone previous weathering and subsequent modification by humans. Nevertheless, mound soils are useful benchmarks for some pedologic studies since they provide time lines for evaluating minimum rates for development of argillic and albic horizons, as well as attainment of the Alfisol order. 相似文献
18.
天山北麓灌溉绿洲的形成和发展 总被引:18,自引:11,他引:18
17世纪以前,天山北麓是以牧为主地区,由“兵屯”建立的古代绿洲仅在交通要道呈星、点分布,且屡兴屡废。18-20世纪中叶,由清朝到民国,大力发展屯田,使社会发展进入半农半牧时期,这里形成的旧绿洲,呈断续岛状小片。1949年以后,由大规模农垦建立的新绿洲群,把分散小片旧绿洲联结在一起,形成与天山相平行绿洲带。本区绿洲形成特点是由屯垦和内地移民发展起来,起步虽晚,但发展很快;而且古绿洲、旧绿洲和新绿洲之间有延续性,不象塔里大盆地的很多古代绿洲已沦为沙漠、戈壁或风蚀地。 相似文献
19.
Glaciogene sedimentary rocks have been found in modem tills of the Grove Mountains, east Antarctica during the 1998 - 1999 Chinese National Antarctic Research Expedition (CHNARE). Based on the lithilogic and sedimentary features, these sedimentary rocks are correlated with Cenozoic sedimentary strata of the Pagodroma Group in the neighboring Prince Charles Mountains and the Sorsdal Formation in VestFold Hills. Sedimentary clasts contain sparsely Late Tertiary spores and pollens, including : Toroisporis ( Lygodiaceae), Osmunda, Granulatisporites ( Pteridaceae?) , Polypodiaceae, Podocarpus , Araucariaceae, Artemisia , Rhus , Nothofagidites , Proteacidites (Proteaceae) , Quercus , Fraxinoipollenites ( Oleaceae ) , Oleoidearumpollenites( Oleaceae ), Operculumpollis, and Tricolpopollenites. Most of the pollen and spores contained in these samples originate from local sources according to the conditions of their preservations as well as correlations with the microfossil assemblages found in the neighboring areas. The majority of the pollen assemblages, as represented by Podocarpus and Nothofagus, belong to the Weddellian biogeocenose, however some exotic components from the old sedimentary basement rocks may have been included during erosion of the proximal ice sheet. If the source areas of glaciogenic sedimentary rocks that bear the pollen and spores are assumed to be local, or in the up glacier areas, the pollen assemblages in these samples might represent an inland flora during a warmer period of the ice-sheet evolutionary history. The finding of the Artemisia and Chenopodiaceae in the pollen assemblages implies that they may belong to late Tertiary (most probably Pliocene). The absence of diatoms in the samples analyzed may indicate that there are no Cenozoic marine strata in the interior of the east Antarctica beyond the Grove Mountains. The significances of the finding of the Nothofagus in these pollen assemblages are discussed on the basis of current knowledge about the age, distribution and ecological conditions of this kind of fossils found in Sirius Group or other strata outcropped in Antarctica. As a preliminary conclusion, we think that the existence of the Cenozoic glaciogenenic rocks and their pollen assemblages present new evidence for a large scale glacial retreat history in Grove Mountains of east Antarctica, and thus support a dynamic East Antarctic Ice Sheet (EAIS). This is consistent with the interpretations of Webb et al. (1984). 相似文献
20.