视其细,知其大——朱践耳《第三交响曲》第二乐章分析笔记

朱践耳《第三交响曲》第二乐章具有标题性流动音型被中断、抒情性线性旋律被散珠、范型化曲式结构被线性处理的写作特点。虽只是一个局部性的个案,却能给人以“视其细,知其大”的审美体验,故可作为中国当代作曲家交响音乐创作及其个性化特征、时代化特点、中国化特性的范例。

雅鲁藏布江孤柳

我属于大地，也属于天空我有时属于大地有时，却属于天空属于大地时，双脚扎入泥土的深处生根，发芽。

Grain-size Characteristics of Sediments Formed Since 8600 yr B.P. in Middle Reaches of Yarlung Zangbo River in Tibet and Their Paleoenvironmental Significance

Widespread aeolian sediments have been found in the middle reaches of the Yarlung Zangbo River, China, The grain-size characteristics of sediments from Cha＇er Section in the area were analyzed. The results show that the section include one stratum of paleo-mobile dunes, four strata of paleo-semi-fixed dunes, two strata of paleo-fixed dunes, one stratum of sandy immature soils. The paleo-mobile and paleo-semi-fixed dune sand in this section are similar to modem aeolian sand in either grain-size composition or Mz and c distribution. Compared the above types of dunes each other, the content of sand substance decreases, while the content of silt and clay increases for paleo-fixed dunes and sandy immature soils. Combined with age data for each stratum, the analysis shows that these strata are the products of climate changes and the evolution of aeolian landforms. The evolutionary sequence of the paleoclimate and of aeolian activities in the valley since 8600 yr B.P. reveals four stages： 8600-5700 yr B.P., when the paleoclimate was cold and dry, with strong winds, thereby activating dunes; 5700-3600 yr B.P., when it was warm and wet, with weak winds, causing dunes to undergo soil-forming processes; 3600-1900 yr B.P., when climate shifted from cold-dry with strong winds to warm-wet with weak winds, and activated dunes were fixed again; and 1900 yr B.P. -present, when the climate became fine, with weak winds, fixing dunes again.

The Relationship between Normalized Difference Vegetation Index(NDVI) and Climate Factors in the Semiarid Region:A Case Study in Yalu Tsangpo River Basin of Qinghai-Tibet Plateau

The Yalu Tsangpo River basin is a typical semi-arid and cold region in the Qinghai-Tibet Plateau, where significant climate change has been detected in the past decades. The objective of this paper is to demonstrate how the regional vegetation, especially the typical plant types, responds to the climate changes. In this study, the model of gravity center has been firstly introduced to analyze the spatial-temporal relationship between NDVI and climate factors considering the time-lag effect. The results show that the vegetation grown has been positively influenced by the rainfall and precipitation both in moving tracks of gravity center and time-lag effect especially for the growing season during the past thirteen years. The herbs and shrubs are inclined to be influenced by the change of rainfall and temperature, which is indicated by larger positive correlation coefficients at the 0.05 confidence level and shorter lagging time. For the soil moisture, the significantly negative relationship of NDV-PDI indicates that the growth and productivity of the vegetation are closely related to the short-term soil water, with the correlation coefficients reaching the maximum value of o.81 at Lag 0-1. Among the typicalvegetation types of plateau, the shrubs of low mountain, steppe and meadow are more sensitive to the change of soil moisture with coefficients of -0.95, -0.93, -0.92, respectively. These findings reveal that the spatial and temporal heterogeneity between NDVI and climatic factors are of great ecological significance and practical value for the protection of eco-environment in Qinghai-Tibet Plateau.

Debris-flow of Zelongnong Ravine in Tibet

Zelongnong Ravine,a branch ravine of Brahmaputra,is an old large glacier debris-flow ravine.Debris-flows with medium and/or small scales occur almost every year;multiple super debris-flows have also broken out in history,and have caused destructive disaster to local residents at the mouth of ravine and blocked Brahmaputra.The huge altitude difference and the steep slope of the Zelongnong Ravine provide predominant energy conditions for the debris-flow.The drainage basin is located in the fast uplifted area,where the complicated geologic structure,the cracked rock,and the frequent earthquake make the rocks experience strong weathering,thus plenty of granular materials are available for the formation of debris-flows.Although this region is located in the rain shadow area,the precipitation is concentrated and most is with high intensity.Also,the strong glacier activity provides water source for debris-flow.According to literature reviews,most debris-flows in the ravine are induced by rainstorms,and their scales are relatively small.However,when the melted water is overlaid,the large scale debris-flows may occur.Parametric calculation such as the flow velocity and the runoff is conducted according to the monitoring data.The result shows that large debris-flows can be aroused when the rainstorm and the melted water are combined well,but the possibility of blocking off Brahmaputra is rare.The occurrence of the super debris-flows is closely related to the intense glacier activity(e.g.,glaciersurge).They often result in destructive disasters and are hard to be prevented and cured by engineering measures,due to the oversized scales.The hazard mitigation measures such as monitoring and prediction are proposed.

Analysis of Longitudinal Profiles along the Eastern Margin of the Qinghai-Tibetan Plateau

Resulting from the collision of the Eurasian and Indian plates, the Qinghai-Tibetan Plateau is commonly known as the ＇roof of the world＇. Collectively the Yarlung Tsangpo, Nu, Laneang, Yangtze, Yalong, and Yellow River basins drain the eastern margin of the plateau. In this paper, we utilize Shuttle Radar Topography Mission elevation data to examine morphometric and relief attributes of these basins to reveal insights rates of incision. A robust into tectonic activity and technique using Maflab is proposed to alleviate errors associated with SRTM data in the derivation of river longitudinal profiles. Convex longitudinal profiles are interpreted to be a product of uplift rates that exceed rates of channel incision along the entire margin of the Qinghai- Tibetan Plateau. Highest relief towards the south reflects extensive fluvial incision. High relief is also prominent along major active faults. Erosion patterns are related to distance from knickpoints. Highest rates of erosion and incision are evident towards the south, with decreasing values towards the north, suggesting a link between tectonic activity and erosion.

Influence of Eco-friendly Manures on Leaf Biomass Production of a Traditional Medicinal Plant Adhatoda vasica Nees under Upper Brahmaputra Valley Agroclimatic Zone

Effect of different organic manures on production of leaf biomass of a potential medicinal plant Adhatoda vasica Nees. was studied at Dibrugarh University under Upper Brahmaputra Valley Agroclimatic Zone of India during 2008-2010. The aim was to know about the agronomic requirements of the wild medicinal plant for its organic cultivation. The plant reproduces by vegetative means through stem cutting. The nursery plants were prepared from the terminal soft-wood cuttings. The experiments were laid down in RBD with 3 m ×6 m block sizes. Cowdung, compost and vermicompost were used as organic manure. Manures were applied at three levels eg. cowdung at 12.0, 19.5 and 27.0 t ha-1 compost at 7.5, 15.0 and 27.7 t ha-1 and vermicompost at 2.5, 3.0 and 3.75 t ha-1. Eighty percent of every dose was applied one week ahead of plantation and the rest was applied after two months of plantation. Irrigation was not necessary as usual rainfall occurred during the period. Hand weeding was done first time after two months of plantation and again just before application of the second part of the manure. Mature leaves were first harvested by picking them in the first week of October to avoid loss due to leaf fall and finally all the leaves were harvested by teaming the branches in second week of November. In the next year, the mature leaves of the newly sprouted branches on the teamed plants were harvested in May and the final harvest was done by teaming the branches again in October. The total leaf biomass was expressed in t ha-1 （dry wt.）. The total nitrogen in the manure was determined by kjeldahl method, phosphorus by spectrophotometric method and potassium by flame photometric method, pH in 1：5 water suspension and organic matter by Walkley and Black＇s titration method. Maximum leaf biomass （2.74 t ha1） and economic benefit （Rs. 30,941 ha-1） were obtained in cowdung at 27.0 t ha-1 followed by cowdung at 19.5 t ha-1（2.50 t hal and Rs. 26,955 ha-1）, compost at 22.7 t ha-1 （2.35 t ha-1 and Rs. 22,132 hal）. Organic cultivation ofA. vasica, using locally available and cheap organic manures like cowdung and compost is highly encouraging. The technique is eco-friendly and its value will be many times more if it is calculated in terms of environmental health. The technique is therefore, recommended for sustainable management of the wild and important medicinal plant of this Agroclimatic Zone. Vermicompost is not advisable because of its higher input cost than the others.

An Analysis of Wetland Degradation in the Dimoria Region of Assam, India

The wetlands of the Brahmaputra valley include lake-like natural water bodies locally known as ＇beel＇, and degenerated lakes, which are often called as swamps. The role of such wetlands in socio-economic condition of the people is significant from various angles. Apart from the wetlands act as the ideal habitats for feeding, nesting and breeding of a large variety of fishes, birds and other aquatic animals, these features maintain the environmental quality of the region. Present study has been conducted primarily in eight selected beels in the Dimoria region, which is located almost at the south-central part of the Brahmaputra valley. The water and soil samples from these wetlands had been collected using random sampling technique and analyzed to know about the nature of degradation of the wetlands. Once highly productive wetland waters now show very low DO, high BOD and COD, indicating dwindling productivity of fish and other aquatic resources. Higher value of pH in soils of most of the wetlands found probably due to the impact of industrial effluents and urban sewage and use of chemical fertilizers in the paddy field of the fringe areas, which again create toxic environment and ultimately reduces fish productivity.

Multivariant statistical analysis for diagenetic information of chert from southern Tibet,China

There are large scale chert formations of different ages exposed widely in southern Tibet, along Yarlung-Zangbo suture zone. The typical chert specimens were sampled from Pengcuolin, Xialu and Zongzhuo profiles. Multivariate statistical analysis is applied for effectively extracting the geochemical information of the chert, and the raw data are processed by R-factor analysis. The first, second and third factors representing terrigenous, authigenic and hydrothermal constituents are extracted from the analysis results. From Pengcuolin, Xialu to Zongzhuo chert profiles, the variance ratios of continental and authigenetic factors become higher （ 51. 1% →62.9 % →91.6 % ）, while hydrothermal factor rapidly decrease （ 40. 9 % →32.2 % →0 ）. This tend- eney also present in the analysis for traee elements, indicating that Pengeuolin chert is hydrothermal origin, The Zongzhuo chert belong to normal sedimentation and the Xialu chert exhibit normal deposition interacted with hydrothermal sedimentation. The facts provide significant implications for understanding the diagenetic and palaeomineralization information of southern Tibet.

Early Ordovician strongly peraluminous granite in the middle section of the Yarlung Zangbo junction zone and its geological significance

LA-ICP-MS zircon U-Pb isotopic dating and rock geochemical analysis were done of the Xarru granite in the middle section of the Yarlung Zangbo junction zone. Zircon 2-6pb/Z38u weighted mean ages of 474.9±2.3 and 478.3±1.7 Ma have been obtained for two gneiss granite samples respectively, which represent the formation age of the granite. This is the first discovery of the Early Ordovician magmatism in the Yarlung Zangbo junction zone. The rocks are high-K calcic-alkalic granite, contain tour- maline but not hornblende, with aluminum saturation index （ASI） of A/CNK〉I.1 （1.10-1.20）, and are enriched in Rb, Th and U and relatively depleted in Ba, Nb, Sr, Zr, Ti and Eu. They are strongly peraluminous S-type granite, resulting from partial melting of argillaceous components in the crust in a syn-collisional setting. According to previous studies as well as the analy- sis in this paper, the formation of the Xarru granite is probably related to the Andean-type orogeny in the process of subduction of the Proto-Tethys Ocean towards the Gondwanaland, and it is a product of partial melting of the thickened upper crust as a result of collision between blocks or micro-blocks in the northern margin of the Gondwana supercontinent in the process of oceanic subduction. The Xarru granite is identified as the Early Ordovician granite, indicating that the wall rocks had probably formed in the Cambrian or Precambrian.

Quantitative Classification and Ordination of Plant Communities in the Upper and Middle Reaches of the Yarlung Zangbo River Basin

Based on vegetation survey data and environmental data of the Yarlung Zangbo River Basin, we conducted a quantitative ecological analysis of the vegetation community composition and the relationship between species and the environment in the study area. The results showed that 44 sampling sites and 68 plant species in the study area can be classified into seven subtypes: Artemisia minor + Stipa purpurea;Artemisia demissa + Stipa purpurea + Artemisia wellbyi;Kobresia pygmaea;Trikeraia hookeri;Sophora moorcroftiana + Cotoneaster multiflorus + Pennisetum centrasiaticum;Artemisia frigida;Potentilla fruticosa + Orinus thoroldii. Detrended correspondence analysis(DCA) indicated that both longitude and altitude play important roles in site and species distribution patterns. In addition, canonical correspondence analysis(CCA) revealed that in the upper and middle reaches of the Yarlung Zangbo River Basin, changes in temperature and precipitation caused by longitude are the main factors controlling the formation and transition of vegetation community types. Moreover, natural vegetation could be divided into three types: desert steppe community(source area), alpine steppe community(middle reaches region), and shrub community(confluence of Yarlung Zangbo River and Nyangqu River).

Community Structure and Diversity Distribution Pattern of Sandy Plants in the Middle and Upper Reaches of the Yarlung Zangbo River

The Yarlung Zangbo River Basin is an important populated area in Tibet, and its plant community structure and diversity pattern have attracted the attention of many scholars. In this paper, the distribution pattern of plant diversity and the environmental factors impacting it in the middle and upper reaches of the Yarlung Zangbo River are revealed and discussed through sample surveys and climate and habitat data. The results show that the plant communities in the study area can be divided into seven types according to the dominant species: Artemisia minor + Stipa purpurea, Artemisia wellbyi + Festuca ovina, Potentilla fruticosa + Orinus thoroldii, Trikeraia hookeri + Artemisia frigida, Kobresia pygmaea, Sophora moorcroftiana + Artemisia hedinii, and Sophora moorcroftiana + Pennisetum centrasiaticum. Plant diversity decreases with decreasing longitude, increasing latitude, and increasing altitude;and the diversity distribution pattern in the study area has distinct zonal characteristics. Water and heat are the main factors which affect the distribution of vegetation types. The explanation rates of water and heat for the plant diversity distribution pattern were 19.3% and 5.7%, respectively, while the spatial variation explained by these two factors together was 60.8%. Therefore, the coupling effect is obvious.

Zircon SHRIMP geochronology and Nd-Pb isotopic characteristics of the meta-basalt in the central part of Tibetan Plateau's Qiangtang region

A small-sized meta-basic rock system is discovered in Qilongwuru Gully of Central Qiangtang’s Shuanghu region and contains a meta-basalt and garnet-bearing plagioclase amphibolite.The zircon U/Pb age of this meta-basalt by SHRIMP analysis is463.3±4.7 Ma,suggesting that this lava formed in the Middle Ordovician,and is consistent with that of the meta-basic rocks in the Taoxing Lake and Guoganjianian Mountain ophiolite found in the Qiangtang plate.As this lava system bears similar geochemistry to N-MORB,it might be a component of ophiolite that represents the trail of the extinction of the Proto-Tethys,suggesting that the formation of Proto-Tethys oceanic basin in the Longmu Co-Shuanghu suture zone could date as far back as to the Middle Ordovician.Isotopic geochemical analysis indicates that the magma source area consists of both depleted mantle(DM)and enriched mantle(EMII)end members and bears Dupal anomaly,similar to that of the Paleo-Tethys in the Neo-Tethys represented by the Yarlung-Tsangpo suture zone,the Paleo-Tethys represented by the Changning-Menglian suture zone,and the Paleo-Tethys in Sanjiang region.This suggests that they have inherited the attribute of the Proto-Tethys mantle domain,and the Longmu Co-Shuanghu suture zone may be a representative of the northern boundary of Gondwana.

Processes of initial collision and suturing between India and Asia

The initial collision between Indian and Asian continents marked the starting point for transformation of land-sea thermal contrast,uplift of the Tibet-Himalaya orogen,and climate change in Asia.In this paper,we review the published literatures from the past 30 years in order to draw consensus on the processes of initial collision and suturing that took place between the Indian and Asian plates.Following a comparison of the different methods that have been used to constrain the initial timing of collision,we propose that the tectono-sedimentary response in the peripheral foreland basin provides the most sensitive index of this event,and that paleomagnetism presents independent evidence as an alternative,reliable,and quantitative research method.In contrast to previous studies that have suggested collision between India and Asia started in Pakistan between ca.55 Ma and50 Ma and progressively closed eastwards,more recent researches have indicated that this major event first occurred in the center of the Yarlung Tsangpo suture zone(YTSZ) between ca.65 Ma and 63 Ma and then spreading both eastwards and westwards.While continental collision is a complicated process,including the processes of deformation,sedimentation,metamorphism,and magmatism,different researchers have tended to define the nature of this event based on their own understanding,an intuitive bias that has meant that its initial timing has remained controversial for decades.Here,we recommend the use of reconstructions of each geological event within the orogenic evolution sequence as this will allow interpretation of collision timing on the basis of multidisciplinary methods.

Constraining the timing of the India-Asia continental collision by the sedimentary record

Placing precise constraints on the timing of the India-Asia continental collision is essential to understand the successive geological and geomorphological evolution of the orogenic belt as well as the uplift mechanism of the Tibetan Plateau and their effects on climate,environment and life.Based on the extensive study of the sedimentary record on both sides of the Yarlung-Zangbo suture zone in Tibet,we review here the present state of knowledge on the timing of collision onset,discuss its possible diachroneity along strike,and reconstruct the early structural and topographic evolution of the Himalayan collided range.We define continent-continent collision as the moment when the oceanic crust is completely consumed at one point where the two continental margins come into contact.We use two methods to constrain the timing of collision onset:(1) dating the provenance change from Indian to Asian recorded by deep-water turbidites near the suture zone,and(2) dating the age of unconformities on both sides of the suture zone.The first method allowed us to constrain precisely collision onset as middle Palaeocene(59±l Ma).Marine sedimentation persisted in the collisional zone for another 20-25 Ma locally in southern Tibet,and molassic-type deposition in the Indian foreland basin did not begin until another 10-15 Ma later.Available sedimentary evidence failed to firmly document any significant diachroneity of collision onset from the central Himalaya to the western Himalaya and Pakistan so far.Based on the Cenozoic stratigraphic record of the Tibetan Himalaya,four distinct stages can be identified in the early evolution of the Himalayan orogen:(1) middle Palaeocene-early Eocene earliest Eohimalayan stage(from 59 to 52 Ma):collision onset and filling of the deep-water trough along the suture zone while carbonate platform sedimentation persisted on the inner Indian margin;(2) early-middle Eocene early Eohimalayan stage(from 52 to 41 or 35 Ma):filling of intervening seaways and cessation of marine sedimentation;(3) late Eocene-Oligocene late Eohimalayan stage(from 41 to 25 Ma):huge gap in the sedimentary record both in the collision zone and in the Indian foreland;and(4) late Oligocene-early Miocene early Neohimalayan stage(from 26 to 17 Ma):rapid Himalayan growth and onset of molasse-type sedimentation in the Indian foreland basin.

Temperate ice layer found in the upper area of Jima Yangzong Glacier,the headstream of Yarlung Zangbo River

For the first time we investigate the basal thermal condition in the upper area of Jima Yangzong Glacier, the headstream of Yarlung Zangbo River, using ground-penetrating radar techniques. With common offset and common mid-point surveys we analyze the radar velocities in ice with respect to cold-temperate ice transi- tion surface （0.1751 0.0028 m ns-~） and ice-bedrock interface （0.1657 ＋ 0.0033 m ns-a）, indicating a radar velocity of 0.1410 4- 0.0154 m ns-1 for the temperate ice layer （16.6 ~ 1.8 m）. We estimate that the temperate ice layer has a water content of around 6 % 4- 4 %, suggesting that the Jima Yangzong Glacier, previously known as continental-type, now possibly becomes polythermal.

Analysis of the Water Environmental Capacity of Zhongba-Nyingchi Section of the Yarlung Tsangpo River

The Yarlung Tsangpo River,the longest river in Tibet,houses most of the population and economy in Tibet Autonomous province.Under the rapid development of economy and society in Tibet,the pollution in the Yarlung Tsangpo River basin has rapidly increased.Evaluating water quality and water environmental capacity is needed for water resource management in Tibet.This study used a single factor evaluation method to evaluate water quality of the Zhongba-Nyingchi section of the Yarlung Tsangpo River based on measured data of CODcr, NH3-N and TP in the study area.Based on these data,determinations of ideal water environmental capacity, emissions of pollutants and remaining water environmental capacity of the study area were made by a one-dimensional steady water quality model under either section-head control or cross-section control.The data indicate that most of the monitoring sections in the study area experienced good water quality.The three pollutants all had large remaining water environmental capacity generally,but TP exceeded state levels in the two upstream functional areas,and levels above state standards of CODcr and TP were found in several calculation cells of the two downstream functional areas.Therefore,emissions of pollutants need to be reduced to protect the water environment quality of the Yarlung Tsangpo River.