[Objective] Through the investigation of weeds in Coffea arabica orchads in NuJiang River basin, this study aimed to provide scientific guidance for the weed control and improving the ecological and economic benefits ...[Objective] Through the investigation of weeds in Coffea arabica orchads in NuJiang River basin, this study aimed to provide scientific guidance for the weed control and improving the ecological and economic benefits of the plantation of Cof- fea arabica. [Method] The types of weeds and the characteristics of weed occur- rence in Coffea arabica orchads in Nujiang River basin were investigated from July to August in 2012. [Result] The results showed that there were 69 types of weeds belonging to 21 families in Coffea arabica orchads. The predominant harmful types were shown as follows： Commelina nudiflora L. ＋ Leptochloa chinensis, Cyperus ro- tundus L. ＋ Bidens pilosa L. ＋ Eleusine indica, Imperata cylindrical ＋ Ageratum conyzoides L. ＋ Eupatorium odoratum L., Ageratum conyzoides L. ＋ Digitaria san- guinalis （L.） Scop. The preponderant weeds consisted mainly of 10 species, namely, Cyperus rotundus L., Commelina nudiflora L., Leptochloa chinensis, Digitaria san- guinalis （L.） Scop, Imperata cylindrical, Bidens pilosa L., Ageratum conyzoides L, E- upatorium odoratum L., Eleusine indica and Chenopodium serotinum L. [Conclusion] The result from this study is of great significance for the plantation of Coffea arabica in Nujiang River basin, as well as the control of weeds.展开更多
Based on the data of sunshine duration,cloud cover and relative humidity from 9 stations in 1981-2008,the spatial and temporal distribution and change trend of total solar radiation in river valley basin of Nujiang we...Based on the data of sunshine duration,cloud cover and relative humidity from 9 stations in 1981-2008,the spatial and temporal distribution and change trend of total solar radiation in river valley basin of Nujiang were analyzed,as well as its impact factors.The results showed that annual solar radiation decreased obviously in Nujiang basin from 1981 to 1997,with the rate of-161.1 MJ/(m2·10 a),while it went up after 1997 at the rate of 111.3 MJ/(m2·10 a).Annual total cloud cover showed significant decrease trend with the rate of 1.8%/10 a,but annual low cloud cover increased at the rate of 3.2%/10 a.Contrary to the change trend of annual solar radiation,relative humidity rose at the increase of 3.1%/10 a from 1981 to 1997 and decreased significantly at the rate of 5.6%/10 a in 1997-2008.The change of water vapor pressure was consistent with relative humility change.Low cloud cover was the main impact factor of total solar radiation and had a negative correlation with total solar radiation.展开更多
Ophiolites are widespread along the Bangong-Nujiang suture zone, northern Tibet. However, it is still debated on the formation ages and tectonic evolution process of these ophiolites. The Zhongcang ophiolite is a typi...Ophiolites are widespread along the Bangong-Nujiang suture zone, northern Tibet. However, it is still debated on the formation ages and tectonic evolution process of these ophiolites. The Zhongcang ophiolite is a typical ophiolite in the western part of the Bangong-Nujiang suture zone. It is composed of serpentinized peridotite, cumulate and isotropic gabbros, massive and pillow basalts, basaltic volcanic breccia, and minor red chert. Zircon SHRIMP Ue Pb dating for the isotropic gabbro yielded weighted mean age of 163.4 ± 1.8 Ma. Positive zircon ε Hf(t) values(+15.0 to +20.2) and mantle-like σ^(18)O values(5.29 ±0.21)% indicate that the isotropic gabbros were derived from a long-term depleted mantle source. The isotropic gabbros have normal mid-ocean ridge basalt(N-MORB) like immobile element patterns with high Mg O, low TiO_2 and moderate rare earth element(REE) abundances, and negative Nb,Ti, Zr and Hf anomalies. Basalts show typical oceanic island basalt(OIB) geochemical features, and they are similar to those of OIB-type rocks of the Early Cretaceous Zhongcang oceanic plateau within the Bangong-Nujiang Ocean. Together with these data, we suggest that the Zhongcang ophiolite was probably formed by the subduction of the Bangong-Nujiang Ocean during the Middle Jurassic. The subduction of the Bangong-Nujiang Tethyan Ocean could begin in the Earlye Middle Jurassic and continue to the Early Cretaceous, and finally continental collision between the Lhasa and Qiangtang terranes at the west Bangong-Nujiang suture zone probably has taken place later than the Early Cretaceous(ca. 110 Ma).展开更多
The Tiegelongnan deposit is a newly discovered super-large porphyry-epithermal Cu-（Au） deposit in the western part of the Bangong Co-Nujiang metallogenic belt, Tibet（China）. Field geology and geochronology indicat...The Tiegelongnan deposit is a newly discovered super-large porphyry-epithermal Cu-（Au） deposit in the western part of the Bangong Co-Nujiang metallogenic belt, Tibet（China）. Field geology and geochronology indicate that the porphyry mineralization was closely related to the Early Cretaceous intermediate-felsic intrusions（ca. 123–120 Ma）. Various epithermal ore and gangue mineral types were discovered in the middle-shallow part of the orebody, indicating the presence of epithermal mineralization at Tiegelongnan. Potassic, propylitic, phyllic and advanced argillic alteration zones were identified. 40Ar/39Ar dating of hydrothermal biotite（potassic zone）, sericite（phyllic zone）, and alunite（advanced argillic zone） in/around the ore-bearing granodiorite porphyry yielded 121.1±0.6 Ma（1σ）, 120.8±0.7 Ma（1σ） and 117.9±1.6 Ma（1σ）, respectively. Five hydrothermal mineralization stages were identified, of which the Stage IV pyrite was Rb-Sr dated to be 117.5±1.8 Ma（2σ）, representing the end of epithermal mineralization. Field geology and geochronology suggest that both the epithermal and porphyry mineralization belong to the same magmatic-hydrothermal system. The Tiegelongnan super-large Cu-（Au） deposit may have undergone a prolonged magmatichydrothermal evolution, with the major mineralization event occurring at ca.120–117Ma.展开更多
As a typical orogenic gold deposit in Tibet,Shangxu gold deposit is located at the Bangong Lake–Nujiang River Metallogenic Belt in the south of Qinghai–Tibet Plateau.In this paper,zircon U-Pb dating,trace elements a...As a typical orogenic gold deposit in Tibet,Shangxu gold deposit is located at the Bangong Lake–Nujiang River Metallogenic Belt in the south of Qinghai–Tibet Plateau.In this paper,zircon U-Pb dating,trace elements and Hf isotopic analysis were performed on Au-bearing quartz veins in the Shangxu gold deposit.Zircons from Au-bearing quartz veins can be divided into three types:detrital,magmatic,and hydrothermal zircons.There are two age peaks in detrital zircons:ca.1700 Ma and ca.2400 Ma.There are two groups of concordant ages including 157±4 Ma(MSWD=0.69)and 120±1 Ma(MSWD=0.19)in magmatic zircons,in whichεH f(t)value of ca.120 Ma from the magmatic zircons range from+8.24 to+12.9.An age of 119±2 Ma(MSWD=0.42)was yielded from hydrothermal zircons,and theirεH f(t)values vary between+15.7 and+16.4.According to sericite Ar-Ar age,this paper suggests that an age of 119±2 Ma from hydrothermal zircons represent the formation age of the Shangxu gold Deposit,and its mineralization should be related to the collision between Lhasa Block and Qiangtang Block.The metallogenic age is basically the same as the diagenetic age of Mugagangri granite,andεH f(t)value of hydrothermal zircon is significantly higher than that of the contemporaneous magmatic zircon,which indicates that there is a genetic relationship between the gold mineralization and the deep crust-mantle magmatism.展开更多
Objective As the third most important copper polymetallic metallogenic belt in Tibet, the Bangongco-Nujiang metallogenic belt （BNMB） has attracted much attention among geoscientists all over the world （Lin Bin et ...Objective As the third most important copper polymetallic metallogenic belt in Tibet, the Bangongco-Nujiang metallogenic belt （BNMB） has attracted much attention among geoscientists all over the world （Lin Bin et al., 2017a）. There are two ore clusters in the westem of BNMB, the Duolong giant porphyry-epitherrnal Cu （Au, Ag） ore cluster and the Ga＇erqiong-Galalelarge porphyry- skarn Cu （Au） ore cluster （Lin Bin et al., 2017a; 2017b）. Now, the latest exploration advances show that the Kuga project is the first economic porphyry-skam copper deposit in the eastern of BNMB, with over 0.4 Mt melt copper （333＋334） @ 0.9%. However, the Kuga deposit is poorly studied about its diagenetic age. In this study, we present a zircon U-Pb LA-ICP-MS dating of ore-bearing biotite granite, in order to identify the time of the ore- related magmatism and reveal the relationship with the westem of BNMB.展开更多
There is a long-term dispute at Moho depth across the Bangong-Nujiang suture (BNS). Due to the complicated and changeable seismic geological condition, it is not easy to acquire images of the reflective Moho in centra...There is a long-term dispute at Moho depth across the Bangong-Nujiang suture (BNS). Due to the complicated and changeable seismic geological condition, it is not easy to acquire images of the reflective Moho in central Tibet. In the support of the SinoProbe project, a series of deep seismic reflection profiles were conducted to image Moho structure across the BNS and the Qiangtang terrane. These profiles extend from the northern Lhasa terrane to the Qiangtang terrane crossing the BNS. Both shot gathers and migration data show clear Moho images beneath the BNS. The Moho depth varies from 75.1 km (~24 s TWT) beneath the northmost Lhasa terrane to 68.9 km (~22 s TWT) beneath southmost Qiangtang terrane, and rises smoothly to 62.6 km (~20 s TWT ) at ~28 km north of the BNS beneath the Qiangtang terrane. We speculate that the Moho appears a 6.2 km sharp offset across the BNS and becomes ~12.5 km shallower from the northmost Lhasa terrane to the south Qiangtang terrane at ~28 km north of the BNS. The viewpoint of Moho depth across the BNS based on deep seismic reflection data is inconsistent with the previous 20 km offset.展开更多
Permian system is one of the best developed systems in Sanjiang area. In Yidun\|Zhongdian and in Zhiso\|Muli, The Lower Permian is clastics\|carbonates\|volcanics with interbeds of siliceous sediments, Whereas the Upp...Permian system is one of the best developed systems in Sanjiang area. In Yidun\|Zhongdian and in Zhiso\|Muli, The Lower Permian is clastics\|carbonates\|volcanics with interbeds of siliceous sediments, Whereas the Upper Permian is composed of lower part of basic volcanics and upper part of clastics\|carbonates with a total thickness of 1000～4000 meters .In Zhongzha (Batang)\|Jingping region, It is mainly carbonates of 217～1320 meters thick, But in Jingping proper, there occur about 5000 meters thick basalts of early late Permian . From Batang to Benzinan along the Jinshajiang river , the lower Permian is clastics\|volcanics\|carbonates formation with interbeds of siliceous sediments and spilite formation; Whereas the Upper Permian is clastics with volcanic interbeds; The total thickness being 3700 to 7100 meters. In Jiangda—Mangco (Mangkang), It is clastic\|carbonate\|volcanic formation of 1100 to 2400 meters . In Tuoba (Qamdo)—Haitong (Mankang)—Ximi (Mujiang ), It is mainly clastics\|carbonates formation , the Upper Permian being coal\|bearing clastics sequence and the total thickness being 700～2500 meters ,In Zhado—Zhasuosuo (Mangkang)—Deqing—Qinggu—Qinghong, It is clastic\|carbonate\|volcanic formation, locally with coal\|bearing clastics of Upper Permian and the total thickness of mainly carbonate formation and clastic formation with coal\|bearing clastic formation of Uppermian, is 800 to 2000 meters. In the whole area , the Permian strata were slightly metamorphosed, locally more intensively metamorphosed up to amphibolite facies. The fossils found belong to fusulinids, coral, brachiopods,ammonite,bivalve, gastropods, bryozoa,foraminifera, trilobite, algae ,porifera (sponge), and continental plant . Besides the Gondwana cold\|water type components of brachiopods found in Baoshan, the fossils belong mainly to Cathaysian biota, especially to South China type. In some places such as Mangkang, Guxue (Dewong), to South China type. In some places such as Mangkang, Guxue (Dewong), and Wachang (Muli), the resedimented Late Carboniferous fusulinid fossils can be found in the clastic limestone of Lower Permian, and the Early Permian or even Middle to Late Carboniferous fusulinid fossils found in Upper Permian classic limestone. All these suggest the resedimentation of biolimestone blocks or fragments related to fault\|volcanism .On the section of Tongba (Muli), the permian is continuous graded upwards into the Triassic, with a transitional zone of fossil.展开更多
The Jinsha River-Lancang River-Nujiang River area is one of the important prospect areas for noble metal and nonferous metal deposits of China. Of a great variety of gold deposits present in this area, the following t...The Jinsha River-Lancang River-Nujiang River area is one of the important prospect areas for noble metal and nonferous metal deposits of China. Of a great variety of gold deposits present in this area, the following types seem to be economically most valuable and promising: tectonic alteration type in ophiolitic melange; polymetallic quartz vein type related to intermediate-acid intrusions; finely disseminated type in fracture zones; mixed hydrothermal type in tectonic fractures of carbonate rocks; hydrothermal type related to subvolcanic rocks; volcanic-hot spring type; submarine volcano exhalation-sedimentary-hydrothermal reformation type. Metallogenic epochs are exclusively Mesozoic and Cenozoic, and ore deposits and orebodies are controlled by linear structures. Magmatic activity has affected gold mineralization in varying degrees, and gold deposits are basically of mesothermal-epithermal type with ubiquitous and intense alterations. Ore-forming materials and hydrothermal solutions show multi-source character.展开更多
On the investigation of the biodiverisities of plant resources of Nujiang River Valley in Nujiang Autonomous Prefacure, Yunnan Province, China, a new species of Ehretia has been described and illustrated as Ehretia re...On the investigation of the biodiverisities of plant resources of Nujiang River Valley in Nujiang Autonomous Prefacure, Yunnan Province, China, a new species of Ehretia has been described and illustrated as Ehretia retroserrata in the arid valley of Nujiang according to the new living state of erect shrub and the characteristics of serrate leave margin, retrose, apiculate, endocarp divided at maturity into 4 1-seeded pyrene and serrate leaves margins by comparison with other species of the genus Ehretia.展开更多
Drought is one of the main natural disasters that cause economic loss in the basins of international rivers such as Nujiang and Lancang rivers. Based on the monthly precipitation and temperature data of 31 meteorologi...Drought is one of the main natural disasters that cause economic loss in the basins of international rivers such as Nujiang and Lancang rivers. Based on the monthly precipitation and temperature data of 31 meteorological stations in Nujiang and Lancang river basins in Yunnan Province during 1965-2013, the standardized precipitation evapotranspiration index(SPEI) in each of the two bio-climate zones was calculated. In addition, the drought process in annual, seasonal and monthly scale was analyzed respectively to reveal the spatial and temporal characteristics and the intensity variation of meteorological drought in Nujiang and Lancang river basins in Yunnan Province. The results showed that there was a significant increasing trend in seasonal(especially winter's) and monthly drought since the late 1970 s; the drought occurred in the two bio-climate zones showed no obvious spatial distinction, and it was synchronized with that occurred throughout Yunnan Province; and in the recent 50 years, the significant increase of drought in the study area may be attributed to the significant rise in temperature, rather than the slight decline of the precipitation.展开更多
The purpose of this paper is to analyze the patterns and factors of targeted poverty alleviation strategy in Nujiang Lisu Autonomous Prefecture,a key area from national contiguous special povertystricken areas in Chin...The purpose of this paper is to analyze the patterns and factors of targeted poverty alleviation strategy in Nujiang Lisu Autonomous Prefecture,a key area from national contiguous special povertystricken areas in China.Data collection took place in August 2015,July 2016 and June 2018,a literature search was carried out between March 2018 and May 2018,peer-reviewed publications in English were considered but to keep down the length of the paper and reduce redundancy,not all literature sources we collected are listed as references.The results show that progress of targeted poverty alleviation and development work in Nujiang Prefecture is generally smooth and obvious.Completing the"13 th Five-Year Plan"for poverty alleviation and development on schedule is also full of challenges and still needs a lot of effort.This study analyzes current situation and challenges for carrying out targeted poverty alleviation strategy in Nujiang Lisu Autonomous Prefecture.These contribute to the efficiency and effectiveness in poverty alleviation work in frontier minority area of China.展开更多
Each nationality has formed unique ethnic culture in the long history. Ethnic culture is spatially reflected byethnic distribution. The distribution of nationalities is influenced by ethnic history, culture, society a...Each nationality has formed unique ethnic culture in the long history. Ethnic culture is spatially reflected byethnic distribution. The distribution of nationalities is influenced by ethnic history, culture, society and religion, alsoaffected by regional physical setting. This paper analyzes the relationship between ethnic distribution pattern and naturalsetting with contrast analytical method. The digital elevation model (DEM) is established on basis of contour map on ascale of 1:250,000 in the Nujiang River basin, Yunnan Province by ArcGIS, a Geographic Information System (GIS)software. Based on DEM, the spatial analysis and statistical function of GIS, the landscape patterns of populationdistribution of the selected minorities is described, and 4 sub-regions are divided in the Nujiang River basin of YunnanProvince while the features and disparity of landscape pattern and its forming mechanism are discussed, along withhistorical and archaeological data. The conclusions are as follow: (1) The ethnic distribution is mosaic in the matrix ofother racial distribution, and have a distinct spatial correlation. (2) For the difference in cultivation between differentnationalities, certain nationality lived in the area suitable for production mode of its own and coincident with appropriategeographical setting. (3) The spatial distribution of settlement spots of the minorities is controlled by the convenience ofwater supply. The landscape pattern of ethnic distribution is closely relative to natural environment.展开更多
The ophiolite-bearing Bangong-Nujiang zone (BNZ) traversing central Tibet from east to west separates the Qiangtang block in the north from the Lhasa block in the south. The Cretaceous of the area includes Chuanba For...The ophiolite-bearing Bangong-Nujiang zone (BNZ) traversing central Tibet from east to west separates the Qiangtang block in the north from the Lhasa block in the south. The Cretaceous of the area includes Chuanba Formation (K 1c ), Duoba Formation (K 1d ), Langshan Formation (K 1l ) and Jiangba Formation (K 2j ). The K 1c is composed of black shale, sandy pelite, siltstone, sandstone, coal beds and volcanic rocks, of shallow marine facies. The K 1 d consists of terrestrial siliciclastics intercalated with some calcareous sandstone beds bearing Orbitolina sp. indicating marine influence. The K 1j is carbonate platform deposits of shallow marine and lagoon. The K 2j is characterized by terrestrial thick massive red conglomerate. An active margin related to B-subduction zone is considered to be the geological setting of the Cretaceous sedimentation.展开更多
Land surface evapotranspiration(ET)is a critical component in the hydrological cycle but has not well been understood in data-scarce areas especially in river basins,like Nujiang River(NRB)which is characterized by la...Land surface evapotranspiration(ET)is a critical component in the hydrological cycle but has not well been understood in data-scarce areas especially in river basins,like Nujiang River(NRB)which is characterized by large elevation gradient and different vegetation zones with complex processes of water and energy exchange.The quality of ET from optical remote sensing is constrained by cloud cover which is common in the NRB in the monsoon seasons.To understand factors controlling the spatial-temporal heterogeneity of ET in NRB,we employed the Variable Infiltration Capacity(VIC)hydrological model by parameter optimization with support of quality controlled remote sensing ET product and observed river runoff series in the river.The modeled ET has increased during 1984-2018,which might be one of the reasons for the runoff decrease but precipitation increase in the same period.ET increase and runoff decrease tended to be quicker within altitudinal band of 2000-4000 m than in other areas in NRB.We observed that ET variation in different climatic zones were controlled by different factors.ET is generally positively correlated with precipitation,temperature,and shortwave radiation but negatively with relative humidity.In the Tundra Climate(Et)zone in the upper reach of NRB,ET is controlled by precipitation,while it is controlled by shortwave radiation in the snow climate with dry winter(Dw)zone.ET increase is influenced by the increase of temperature,wind speed,and shortwave radiation in the middle and downstream of NRB with warm temperate climate,fully humid(Cf)and warm temperate climate with dry winter(Cw).展开更多
The Tibetan Plateau is one of the most complicated geographical units worldwide in terms of its tectonic and environmental background.Although a hotspot for continental weathering and carbon cycling studies,accurate d...The Tibetan Plateau is one of the most complicated geographical units worldwide in terms of its tectonic and environmental background.Although a hotspot for continental weathering and carbon cycling studies,accurate determination of the weathering carbon budget is challenging in this area,especially sink and source flux quantification and the controlling mechanisms.Compared with other major rivers on the plateau,the Nujiang River is characterized by less human disturbance and maintains a relatively pristine state.This study investigates the high spatiotemporal resolution hydrochemistry and dual-carbon isotope composition(δ~(13)C_(DIC)andΔ~(14)C_(DIC))of river water in the Nujiang River Basin.The results revealed that the solutes and dissolved inorganic carbon in the river water are predominantly derived from rock weathering by carbonic and sulfuric acids,mainly due to the carbonate weathering process,and significantly enhanced by deep carbon sourcing from hot springs in the fault zone.The average contributions of geological and modern carbon in the main stream of the Nujiang River are 35.2%and 64.8%,respectively,and sulfide oxidation contributes>90%of sulfate ions in the river water.After considering the involvement of sulfuric acid generated by sulfide oxidation during rock weathering,the calculated consumption fluxes of atmospheric CO_(2) by silicate and carbonate weathering in the watershed were decreased by approximately 52.0%and 37.4%,respectively,compared with those calculated ignoring this process.Rock weathering of the Nujiang River Basin is a“CO_(2) sink”on a short time scale,while the participation of sulfuric acid makes it a“CO_(2) source”on a geological time scale.The high-frequency observations of ion concentrations,elemental ratios,and calculated contributions of different rock weathering materials indicate that carbonate rock weathering is more sensitive to temperature and runoff variations than silicate rock weathering,with the solute contribution from carbonate weathering increasing significantly during monsoon period.The material input from different rock types is dominated by the hydrological pathways and water-rock reaction times in the basin.This study reveals the river solute origins and weathering CO_(2) sequestration effect in response to a monsoonal climate in one of the most representative pristine plateau watersheds in the world,which is of great importance for elucidating the weathering control mechanisms and CO_(2) net sourcesink effect in plateau watersheds.展开更多
Southwestern China contains rich hydropower resources and a high concentration of impoverished people. The acceleration of hydropower development is an important way for promoting the development of impoverished areas...Southwestern China contains rich hydropower resources and a high concentration of impoverished people. The acceleration of hydropower development is an important way for promoting the development of impoverished areas and improving the livelihood assets of rural households. Taking Nujiang Prefecture as our focal area we conducted enterprise interviews and government discussions to arrive at a benefit-sharing mechanism for hydropower development. We found that heavy tax burdens on enterprises, low compensation standards, unreasonable electricity prices and weak development conditions are the main reasons that hydropower development is not accompanied by local economic development and improvement in the livelihoods of rural people. Based on a specific factor model and the theory of persistent income, a theoretical model is proposed and used to assess the scenario before relocation and the scenario after relocation. On this basis, policy recommendations for benefit-sharing mechanisms of hydropower development are proposed.展开更多
The aesthetic perceptions of local residents towards residential landscapes are significant to the protection and sustainable development of regional landscapes, especially in underdeveloped areas with landscape resou...The aesthetic perceptions of local residents towards residential landscapes are significant to the protection and sustainable development of regional landscapes, especially in underdeveloped areas with landscape resources of higher aesthetic value. Using Nujiang Lisu Autonomous Prefecture in Yunnan Province as a case study, we conducted questionnaires with 620 local residents and a logistic regression model to determine aesthetic perceptions and factors affecting these perceptions. We found that local residents in Nujiang hold a relatively high perception of their residential landscapes. A majority of respondents, 75.81%, believe their residential landscapes are beautiful. Eight factors were found to influence the aesthetic perception. In direct influential factors, administrative village located in the protected areas and the standard deviation of the elevation around the administrative village have positive influence; distance from administrative village to county town, the ecological environment has changed in recent years, whether tourism development has a negative impact and wish to live in the city have negative influence. In indirect influential factors, both residential house type and have a television at home have positive influence. Based on these results, we discussed relevant policy suggestions to maintain the aesthetic perceptions held by local residents of their residential landscapes and promote the protection and sustainable development of this valuable landscape in Nujiang.展开更多
基金Supported by the Special Fund for Agro-scientific Research in the Public Interest,China(200903024-02)~~
文摘[Objective] Through the investigation of weeds in Coffea arabica orchads in NuJiang River basin, this study aimed to provide scientific guidance for the weed control and improving the ecological and economic benefits of the plantation of Cof- fea arabica. [Method] The types of weeds and the characteristics of weed occur- rence in Coffea arabica orchads in Nujiang River basin were investigated from July to August in 2012. [Result] The results showed that there were 69 types of weeds belonging to 21 families in Coffea arabica orchads. The predominant harmful types were shown as follows： Commelina nudiflora L. ＋ Leptochloa chinensis, Cyperus ro- tundus L. ＋ Bidens pilosa L. ＋ Eleusine indica, Imperata cylindrical ＋ Ageratum conyzoides L. ＋ Eupatorium odoratum L., Ageratum conyzoides L. ＋ Digitaria san- guinalis （L.） Scop. The preponderant weeds consisted mainly of 10 species, namely, Cyperus rotundus L., Commelina nudiflora L., Leptochloa chinensis, Digitaria san- guinalis （L.） Scop, Imperata cylindrical, Bidens pilosa L., Ageratum conyzoides L, E- upatorium odoratum L., Eleusine indica and Chenopodium serotinum L. [Conclusion] The result from this study is of great significance for the plantation of Coffea arabica in Nujiang River basin, as well as the control of weeds.
基金Supported by National Natural Science Foundation of China(40865008)International Cooperative Project of Ministry of Science and Technology(2009DFA91900)
文摘Based on the data of sunshine duration,cloud cover and relative humidity from 9 stations in 1981-2008,the spatial and temporal distribution and change trend of total solar radiation in river valley basin of Nujiang were analyzed,as well as its impact factors.The results showed that annual solar radiation decreased obviously in Nujiang basin from 1981 to 1997,with the rate of-161.1 MJ/(m2·10 a),while it went up after 1997 at the rate of 111.3 MJ/(m2·10 a).Annual total cloud cover showed significant decrease trend with the rate of 1.8%/10 a,but annual low cloud cover increased at the rate of 3.2%/10 a.Contrary to the change trend of annual solar radiation,relative humidity rose at the increase of 3.1%/10 a from 1981 to 1997 and decreased significantly at the rate of 5.6%/10 a in 1997-2008.The change of water vapor pressure was consistent with relative humility change.Low cloud cover was the main impact factor of total solar radiation and had a negative correlation with total solar radiation.
基金supported by National Natural Science Foundation of China (Grant Nos. 41522204, 91755103 and 41502216)the Ministry of Science and Technology of China(2016YFC0600304)+1 种基金CAGS Research Fund (Grant No. YYWF201704)Chinese Geological Survey Project (Grant Nos. DD20160123-05 and DD20160345)
文摘Ophiolites are widespread along the Bangong-Nujiang suture zone, northern Tibet. However, it is still debated on the formation ages and tectonic evolution process of these ophiolites. The Zhongcang ophiolite is a typical ophiolite in the western part of the Bangong-Nujiang suture zone. It is composed of serpentinized peridotite, cumulate and isotropic gabbros, massive and pillow basalts, basaltic volcanic breccia, and minor red chert. Zircon SHRIMP Ue Pb dating for the isotropic gabbro yielded weighted mean age of 163.4 ± 1.8 Ma. Positive zircon ε Hf(t) values(+15.0 to +20.2) and mantle-like σ^(18)O values(5.29 ±0.21)% indicate that the isotropic gabbros were derived from a long-term depleted mantle source. The isotropic gabbros have normal mid-ocean ridge basalt(N-MORB) like immobile element patterns with high Mg O, low TiO_2 and moderate rare earth element(REE) abundances, and negative Nb,Ti, Zr and Hf anomalies. Basalts show typical oceanic island basalt(OIB) geochemical features, and they are similar to those of OIB-type rocks of the Early Cretaceous Zhongcang oceanic plateau within the Bangong-Nujiang Ocean. Together with these data, we suggest that the Zhongcang ophiolite was probably formed by the subduction of the Bangong-Nujiang Ocean during the Middle Jurassic. The subduction of the Bangong-Nujiang Tethyan Ocean could begin in the Earlye Middle Jurassic and continue to the Early Cretaceous, and finally continental collision between the Lhasa and Qiangtang terranes at the west Bangong-Nujiang suture zone probably has taken place later than the Early Cretaceous(ca. 110 Ma).
基金jointly sponsored by the Public Science and Technology Research Funds Projects,Ministry of Land Resources of the People’s Republic of China(project No.201511017 and 201511022-02)the Basic Research Fund of the Chinese Academy of Geological Sciences(Grant No.YYWF201608)+3 种基金the National Natural Science Foundation of China(Grant No.41402178)Geological Survey Project of the China Geological Survey(project 1212011405040)Golden Dragon Mining Co.Ltd.(project XZJL-2013-JS03)China Scholarship Council
文摘The Tiegelongnan deposit is a newly discovered super-large porphyry-epithermal Cu-（Au） deposit in the western part of the Bangong Co-Nujiang metallogenic belt, Tibet（China）. Field geology and geochronology indicate that the porphyry mineralization was closely related to the Early Cretaceous intermediate-felsic intrusions（ca. 123–120 Ma）. Various epithermal ore and gangue mineral types were discovered in the middle-shallow part of the orebody, indicating the presence of epithermal mineralization at Tiegelongnan. Potassic, propylitic, phyllic and advanced argillic alteration zones were identified. 40Ar/39Ar dating of hydrothermal biotite（potassic zone）, sericite（phyllic zone）, and alunite（advanced argillic zone） in/around the ore-bearing granodiorite porphyry yielded 121.1±0.6 Ma（1σ）, 120.8±0.7 Ma（1σ） and 117.9±1.6 Ma（1σ）, respectively. Five hydrothermal mineralization stages were identified, of which the Stage IV pyrite was Rb-Sr dated to be 117.5±1.8 Ma（2σ）, representing the end of epithermal mineralization. Field geology and geochronology suggest that both the epithermal and porphyry mineralization belong to the same magmatic-hydrothermal system. The Tiegelongnan super-large Cu-（Au） deposit may have undergone a prolonged magmatichydrothermal evolution, with the major mineralization event occurring at ca.120–117Ma.
基金financially supported by the National Natural Science Foundation of China(Grant No.91955208)the National Key Research and Development Program of China(Grant nos.2016YFC0600308 and 2018YFC0604103)a program of China Geological Survey(Grant No.DD2021392)。
文摘As a typical orogenic gold deposit in Tibet,Shangxu gold deposit is located at the Bangong Lake–Nujiang River Metallogenic Belt in the south of Qinghai–Tibet Plateau.In this paper,zircon U-Pb dating,trace elements and Hf isotopic analysis were performed on Au-bearing quartz veins in the Shangxu gold deposit.Zircons from Au-bearing quartz veins can be divided into three types:detrital,magmatic,and hydrothermal zircons.There are two age peaks in detrital zircons:ca.1700 Ma and ca.2400 Ma.There are two groups of concordant ages including 157±4 Ma(MSWD=0.69)and 120±1 Ma(MSWD=0.19)in magmatic zircons,in whichεH f(t)value of ca.120 Ma from the magmatic zircons range from+8.24 to+12.9.An age of 119±2 Ma(MSWD=0.42)was yielded from hydrothermal zircons,and theirεH f(t)values vary between+15.7 and+16.4.According to sericite Ar-Ar age,this paper suggests that an age of 119±2 Ma from hydrothermal zircons represent the formation age of the Shangxu gold Deposit,and its mineralization should be related to the collision between Lhasa Block and Qiangtang Block.The metallogenic age is basically the same as the diagenetic age of Mugagangri granite,andεH f(t)value of hydrothermal zircon is significantly higher than that of the contemporaneous magmatic zircon,which indicates that there is a genetic relationship between the gold mineralization and the deep crust-mantle magmatism.
基金sponsored by Public Science and Technology Research Funds Projects, Ministry of Land Resources of the People’s Republic of China (grants No. 201511017, 201511022-05)the Basic Research Fund of the Chinese Academy of Geological Sciences (grant No. YYWF201608)+1 种基金National Natural Science Foundation of China (grant No. 41402178)China Scholarship Council
文摘Objective As the third most important copper polymetallic metallogenic belt in Tibet, the Bangongco-Nujiang metallogenic belt （BNMB） has attracted much attention among geoscientists all over the world （Lin Bin et al., 2017a）. There are two ore clusters in the westem of BNMB, the Duolong giant porphyry-epitherrnal Cu （Au, Ag） ore cluster and the Ga＇erqiong-Galalelarge porphyry- skarn Cu （Au） ore cluster （Lin Bin et al., 2017a; 2017b）. Now, the latest exploration advances show that the Kuga project is the first economic porphyry-skam copper deposit in the eastern of BNMB, with over 0.4 Mt melt copper （333＋334） @ 0.9%. However, the Kuga deposit is poorly studied about its diagenetic age. In this study, we present a zircon U-Pb LA-ICP-MS dating of ore-bearing biotite granite, in order to identify the time of the ore- related magmatism and reveal the relationship with the westem of BNMB.
文摘There is a long-term dispute at Moho depth across the Bangong-Nujiang suture (BNS). Due to the complicated and changeable seismic geological condition, it is not easy to acquire images of the reflective Moho in central Tibet. In the support of the SinoProbe project, a series of deep seismic reflection profiles were conducted to image Moho structure across the BNS and the Qiangtang terrane. These profiles extend from the northern Lhasa terrane to the Qiangtang terrane crossing the BNS. Both shot gathers and migration data show clear Moho images beneath the BNS. The Moho depth varies from 75.1 km (~24 s TWT) beneath the northmost Lhasa terrane to 68.9 km (~22 s TWT) beneath southmost Qiangtang terrane, and rises smoothly to 62.6 km (~20 s TWT ) at ~28 km north of the BNS beneath the Qiangtang terrane. We speculate that the Moho appears a 6.2 km sharp offset across the BNS and becomes ~12.5 km shallower from the northmost Lhasa terrane to the south Qiangtang terrane at ~28 km north of the BNS. The viewpoint of Moho depth across the BNS based on deep seismic reflection data is inconsistent with the previous 20 km offset.
文摘Permian system is one of the best developed systems in Sanjiang area. In Yidun\|Zhongdian and in Zhiso\|Muli, The Lower Permian is clastics\|carbonates\|volcanics with interbeds of siliceous sediments, Whereas the Upper Permian is composed of lower part of basic volcanics and upper part of clastics\|carbonates with a total thickness of 1000～4000 meters .In Zhongzha (Batang)\|Jingping region, It is mainly carbonates of 217～1320 meters thick, But in Jingping proper, there occur about 5000 meters thick basalts of early late Permian . From Batang to Benzinan along the Jinshajiang river , the lower Permian is clastics\|volcanics\|carbonates formation with interbeds of siliceous sediments and spilite formation; Whereas the Upper Permian is clastics with volcanic interbeds; The total thickness being 3700 to 7100 meters. In Jiangda—Mangco (Mangkang), It is clastic\|carbonate\|volcanic formation of 1100 to 2400 meters . In Tuoba (Qamdo)—Haitong (Mankang)—Ximi (Mujiang ), It is mainly clastics\|carbonates formation , the Upper Permian being coal\|bearing clastics sequence and the total thickness being 700～2500 meters ,In Zhado—Zhasuosuo (Mangkang)—Deqing—Qinggu—Qinghong, It is clastic\|carbonate\|volcanic formation, locally with coal\|bearing clastics of Upper Permian and the total thickness of mainly carbonate formation and clastic formation with coal\|bearing clastic formation of Uppermian, is 800 to 2000 meters. In the whole area , the Permian strata were slightly metamorphosed, locally more intensively metamorphosed up to amphibolite facies. The fossils found belong to fusulinids, coral, brachiopods,ammonite,bivalve, gastropods, bryozoa,foraminifera, trilobite, algae ,porifera (sponge), and continental plant . Besides the Gondwana cold\|water type components of brachiopods found in Baoshan, the fossils belong mainly to Cathaysian biota, especially to South China type. In some places such as Mangkang, Guxue (Dewong), to South China type. In some places such as Mangkang, Guxue (Dewong), and Wachang (Muli), the resedimented Late Carboniferous fusulinid fossils can be found in the clastic limestone of Lower Permian, and the Early Permian or even Middle to Late Carboniferous fusulinid fossils found in Upper Permian classic limestone. All these suggest the resedimentation of biolimestone blocks or fragments related to fault\|volcanism .On the section of Tongba (Muli), the permian is continuous graded upwards into the Triassic, with a transitional zone of fossil.
文摘The Jinsha River-Lancang River-Nujiang River area is one of the important prospect areas for noble metal and nonferous metal deposits of China. Of a great variety of gold deposits present in this area, the following types seem to be economically most valuable and promising: tectonic alteration type in ophiolitic melange; polymetallic quartz vein type related to intermediate-acid intrusions; finely disseminated type in fracture zones; mixed hydrothermal type in tectonic fractures of carbonate rocks; hydrothermal type related to subvolcanic rocks; volcanic-hot spring type; submarine volcano exhalation-sedimentary-hydrothermal reformation type. Metallogenic epochs are exclusively Mesozoic and Cenozoic, and ore deposits and orebodies are controlled by linear structures. Magmatic activity has affected gold mineralization in varying degrees, and gold deposits are basically of mesothermal-epithermal type with ubiquitous and intense alterations. Ore-forming materials and hydrothermal solutions show multi-source character.
文摘On the investigation of the biodiverisities of plant resources of Nujiang River Valley in Nujiang Autonomous Prefacure, Yunnan Province, China, a new species of Ehretia has been described and illustrated as Ehretia retroserrata in the arid valley of Nujiang according to the new living state of erect shrub and the characteristics of serrate leave margin, retrose, apiculate, endocarp divided at maturity into 4 1-seeded pyrene and serrate leaves margins by comparison with other species of the genus Ehretia.
基金Sponsored by Project of Baoshan Municipal Science and Technology Bureau"Study on Ecological Security Pattern of Baoshan City Based on ANNs"
文摘Drought is one of the main natural disasters that cause economic loss in the basins of international rivers such as Nujiang and Lancang rivers. Based on the monthly precipitation and temperature data of 31 meteorological stations in Nujiang and Lancang river basins in Yunnan Province during 1965-2013, the standardized precipitation evapotranspiration index(SPEI) in each of the two bio-climate zones was calculated. In addition, the drought process in annual, seasonal and monthly scale was analyzed respectively to reveal the spatial and temporal characteristics and the intensity variation of meteorological drought in Nujiang and Lancang river basins in Yunnan Province. The results showed that there was a significant increasing trend in seasonal(especially winter's) and monthly drought since the late 1970 s; the drought occurred in the two bio-climate zones showed no obvious spatial distinction, and it was synchronized with that occurred throughout Yunnan Province; and in the recent 50 years, the significant increase of drought in the study area may be attributed to the significant rise in temperature, rather than the slight decline of the precipitation.
基金supported by the Yunnan Provincial Department of Education Science Research Fund(Grant No.2019J0199)Third Party Appraisal of“13th Five-Year Plan”on Nujiang Lisu Autonomous Prefecture carried out by the Yunnan Academy of Social Science.
文摘The purpose of this paper is to analyze the patterns and factors of targeted poverty alleviation strategy in Nujiang Lisu Autonomous Prefecture,a key area from national contiguous special povertystricken areas in China.Data collection took place in August 2015,July 2016 and June 2018,a literature search was carried out between March 2018 and May 2018,peer-reviewed publications in English were considered but to keep down the length of the paper and reduce redundancy,not all literature sources we collected are listed as references.The results show that progress of targeted poverty alleviation and development work in Nujiang Prefecture is generally smooth and obvious.Completing the"13 th Five-Year Plan"for poverty alleviation and development on schedule is also full of challenges and still needs a lot of effort.This study analyzes current situation and challenges for carrying out targeted poverty alleviation strategy in Nujiang Lisu Autonomous Prefecture.These contribute to the efficiency and effectiveness in poverty alleviation work in frontier minority area of China.
文摘Each nationality has formed unique ethnic culture in the long history. Ethnic culture is spatially reflected byethnic distribution. The distribution of nationalities is influenced by ethnic history, culture, society and religion, alsoaffected by regional physical setting. This paper analyzes the relationship between ethnic distribution pattern and naturalsetting with contrast analytical method. The digital elevation model (DEM) is established on basis of contour map on ascale of 1:250,000 in the Nujiang River basin, Yunnan Province by ArcGIS, a Geographic Information System (GIS)software. Based on DEM, the spatial analysis and statistical function of GIS, the landscape patterns of populationdistribution of the selected minorities is described, and 4 sub-regions are divided in the Nujiang River basin of YunnanProvince while the features and disparity of landscape pattern and its forming mechanism are discussed, along withhistorical and archaeological data. The conclusions are as follow: (1) The ethnic distribution is mosaic in the matrix ofother racial distribution, and have a distinct spatial correlation. (2) For the difference in cultivation between differentnationalities, certain nationality lived in the area suitable for production mode of its own and coincident with appropriategeographical setting. (3) The spatial distribution of settlement spots of the minorities is controlled by the convenience ofwater supply. The landscape pattern of ethnic distribution is closely relative to natural environment.
基金DFG-Tibet-Projects SCHN 202/14-1 and attained with the assistance of the AvH.
文摘The ophiolite-bearing Bangong-Nujiang zone (BNZ) traversing central Tibet from east to west separates the Qiangtang block in the north from the Lhasa block in the south. The Cretaceous of the area includes Chuanba Formation (K 1c ), Duoba Formation (K 1d ), Langshan Formation (K 1l ) and Jiangba Formation (K 2j ). The K 1c is composed of black shale, sandy pelite, siltstone, sandstone, coal beds and volcanic rocks, of shallow marine facies. The K 1 d consists of terrestrial siliciclastics intercalated with some calcareous sandstone beds bearing Orbitolina sp. indicating marine influence. The K 1j is carbonate platform deposits of shallow marine and lagoon. The K 2j is characterized by terrestrial thick massive red conglomerate. An active margin related to B-subduction zone is considered to be the geological setting of the Cretaceous sedimentation.
基金supported by the National Natural Science Foundation of China(42171129)the second Tibetan Plateau Scientific Expedition and Research(2019QZKK0208)Yunnan University Talent Introduction Research Project(YJRC3201702)。
文摘Land surface evapotranspiration(ET)is a critical component in the hydrological cycle but has not well been understood in data-scarce areas especially in river basins,like Nujiang River(NRB)which is characterized by large elevation gradient and different vegetation zones with complex processes of water and energy exchange.The quality of ET from optical remote sensing is constrained by cloud cover which is common in the NRB in the monsoon seasons.To understand factors controlling the spatial-temporal heterogeneity of ET in NRB,we employed the Variable Infiltration Capacity(VIC)hydrological model by parameter optimization with support of quality controlled remote sensing ET product and observed river runoff series in the river.The modeled ET has increased during 1984-2018,which might be one of the reasons for the runoff decrease but precipitation increase in the same period.ET increase and runoff decrease tended to be quicker within altitudinal band of 2000-4000 m than in other areas in NRB.We observed that ET variation in different climatic zones were controlled by different factors.ET is generally positively correlated with precipitation,temperature,and shortwave radiation but negatively with relative humidity.In the Tundra Climate(Et)zone in the upper reach of NRB,ET is controlled by precipitation,while it is controlled by shortwave radiation in the snow climate with dry winter(Dw)zone.ET increase is influenced by the increase of temperature,wind speed,and shortwave radiation in the middle and downstream of NRB with warm temperate climate,fully humid(Cf)and warm temperate climate with dry winter(Cw).
基金supported by the National Key Research and Development Program of China (Grant No.2020YFA0607700)the National Basic Science Center Program of Natural Science Foundation of China (Grant No.41888101)+2 种基金the National Natural Science Foundation of China (Grant No.41730857)the Key Research Program of the Institute of Geology&Geophysics,CAS (Grant No.IGGCAS-202204)support from the Youth Innovation Promotion Association CAS (Grant No.2019067)。
文摘The Tibetan Plateau is one of the most complicated geographical units worldwide in terms of its tectonic and environmental background.Although a hotspot for continental weathering and carbon cycling studies,accurate determination of the weathering carbon budget is challenging in this area,especially sink and source flux quantification and the controlling mechanisms.Compared with other major rivers on the plateau,the Nujiang River is characterized by less human disturbance and maintains a relatively pristine state.This study investigates the high spatiotemporal resolution hydrochemistry and dual-carbon isotope composition(δ~(13)C_(DIC)andΔ~(14)C_(DIC))of river water in the Nujiang River Basin.The results revealed that the solutes and dissolved inorganic carbon in the river water are predominantly derived from rock weathering by carbonic and sulfuric acids,mainly due to the carbonate weathering process,and significantly enhanced by deep carbon sourcing from hot springs in the fault zone.The average contributions of geological and modern carbon in the main stream of the Nujiang River are 35.2%and 64.8%,respectively,and sulfide oxidation contributes>90%of sulfate ions in the river water.After considering the involvement of sulfuric acid generated by sulfide oxidation during rock weathering,the calculated consumption fluxes of atmospheric CO_(2) by silicate and carbonate weathering in the watershed were decreased by approximately 52.0%and 37.4%,respectively,compared with those calculated ignoring this process.Rock weathering of the Nujiang River Basin is a“CO_(2) sink”on a short time scale,while the participation of sulfuric acid makes it a“CO_(2) source”on a geological time scale.The high-frequency observations of ion concentrations,elemental ratios,and calculated contributions of different rock weathering materials indicate that carbonate rock weathering is more sensitive to temperature and runoff variations than silicate rock weathering,with the solute contribution from carbonate weathering increasing significantly during monsoon period.The material input from different rock types is dominated by the hydrological pathways and water-rock reaction times in the basin.This study reveals the river solute origins and weathering CO_(2) sequestration effect in response to a monsoonal climate in one of the most representative pristine plateau watersheds in the world,which is of great importance for elucidating the weathering control mechanisms and CO_(2) net sourcesink effect in plateau watersheds.
基金National Natural Science Foundation of China(No.41271146)Key Program of Chinese Academy of Sciences(No.KZZD-EW-06-01)
文摘Southwestern China contains rich hydropower resources and a high concentration of impoverished people. The acceleration of hydropower development is an important way for promoting the development of impoverished areas and improving the livelihood assets of rural households. Taking Nujiang Prefecture as our focal area we conducted enterprise interviews and government discussions to arrive at a benefit-sharing mechanism for hydropower development. We found that heavy tax burdens on enterprises, low compensation standards, unreasonable electricity prices and weak development conditions are the main reasons that hydropower development is not accompanied by local economic development and improvement in the livelihoods of rural people. Based on a specific factor model and the theory of persistent income, a theoretical model is proposed and used to assess the scenario before relocation and the scenario after relocation. On this basis, policy recommendations for benefit-sharing mechanisms of hydropower development are proposed.
基金National Key Technology R&D Program (No. 2008BAH31B01)Key Program of Chinese Academy of Sciences (No. KZZD-EW-06)Key Project of the National Natural Sciences Foundation (No.40830741)
文摘The aesthetic perceptions of local residents towards residential landscapes are significant to the protection and sustainable development of regional landscapes, especially in underdeveloped areas with landscape resources of higher aesthetic value. Using Nujiang Lisu Autonomous Prefecture in Yunnan Province as a case study, we conducted questionnaires with 620 local residents and a logistic regression model to determine aesthetic perceptions and factors affecting these perceptions. We found that local residents in Nujiang hold a relatively high perception of their residential landscapes. A majority of respondents, 75.81%, believe their residential landscapes are beautiful. Eight factors were found to influence the aesthetic perception. In direct influential factors, administrative village located in the protected areas and the standard deviation of the elevation around the administrative village have positive influence; distance from administrative village to county town, the ecological environment has changed in recent years, whether tourism development has a negative impact and wish to live in the city have negative influence. In indirect influential factors, both residential house type and have a television at home have positive influence. Based on these results, we discussed relevant policy suggestions to maintain the aesthetic perceptions held by local residents of their residential landscapes and promote the protection and sustainable development of this valuable landscape in Nujiang.
