元刊《河西藏》考补

本文综合西夏文《过去庄严劫千佛名经》发愿文和《普宁藏》所收汉文发愿文,以及存世碑铭资料,补充梳理了元刊《河西藏》的情况,以期对全面把握现存西夏文佛经的刊行情况及西夏乃至元代佛经的传译有所助益。

新见西夏文《真实名经》考

新见西夏文《圣妙吉祥真实名经》,2022年4月存泰和嘉成拍卖公司,为故宫博物院翁连溪所见本。通过释读并与存世其他版本的对比,发现新见本是目前见到的有关西夏文《真实名经》最全的版本,可以补足俄罗斯科学院东方文献研究所藏本инв.№0728、中国台湾“中央研究院”历史语言研究所傅斯年图书馆藏本和日本天理大学图书馆藏本的内容,不仅为学界提供了解《真实名经》的更多信息,而且堪为研究西夏乃至元代的宗教信仰与社会文化提供重要资料。

Ice-wedge Pseudomorphs Showing Climatic Change Since the Late Pleistocene in the Source Area of the Yellow River, Northeast Tibet

The source area of the Yellow River is located in the northeastern Tibetan Plateau, and is a high-elevation region with the annual mean temperature of -3.9℃. The ice-wedge pseudomorphs discovered in this region are recognized as two types. One was found in sandy gravel beds of the second terrace of the Yellow River. This ice-wedge pseudomorph is characterized by higher ratio of breadth/depth, and are 1-1.4 m wide and about 1 m deep. The bottom border of the ice-wedge pseudomorph is round arc in section. Another discovered in the pedestal of the second terrace has lower ratio of width/depth, and is o.3-1.0 m wide and 1-2 m deep. Its bottom border is sharp. Based on the TL dating, the former was formed at the middleHolocene （5.69±0.43 ka BP and 5.43±0.41 ka BP）, that is, the Megathermal, and the latter was formed at the late Last Glacial Maximum （13.49±1.43 ka BP）. Additionally, the thawing-freezing folders discovered in the late Late Pleistocene proluvium are 39.83±3.84 ka BP in age. The study on the ice-wedge pseudomorphs showed that the air temperature was lowered by up to 6-7℃ in the source area of the Yellow River when the ice-wedge pseudomorphs and thawing-freezing folds developed.

Livelihood Strategy Change and Land Use Change——Case of Danzam Village in Upper Dadu River Watershed,Tibetan Plateau of China

Land use change in rural China since the 1980s, induced by institution reforms, urbanization, industrialization and population increase, has received more attention. However, case studies on how institution reforms affect farmers＇ livelihood strategies and drive land use change are scarce. By means of cropland plots investigations and interviews with farmers, this study examines livelihood strategy change and land use change in Danzam Village of Jinchuan County in the upper Dadu River watershed, eastern Tibetan Plateau, China. The results show that, during the collective system period, as surplus labor forces could not be transferred to the secondary and tertiary industries, they had to choose agricultural involution as their livelihood strategy, then the farmers had to produce more grains by land reclamation, increasing multiple cropping index, improving input of labor, fertilizer, pesticide and adopting advanced agricultural techniques. During the household responsibility system period, as labors being transferred to the secondary and tertiary industries, farmers chose livelihood diversification strategy. Therefore, labor input to grain planting was greatly reduced, which drove the transformation of grain to horticulture, vegetable or wasteland and decrease of multiple cropping index. This study provides a new insight into understanding linkages among institution reforms, livelihood strategy of smallholders and land use change in rural China.

Spatio-temporal variability of periphytic protozoa related to environment in the Niyang River,Tibet,China

The Niyang River, a main tributary of the Yarlung Zangbo River, is an important and typical plateau fiver ecosystem in Tibet, China. At present, few studies have focused on its aquatic living resources and fiver ecology. In this study, the composition, abundance, and diversity of periphytic protozoa were investigated across four seasons from 2008 to 2009 to better understand their spatio-temporal patterns and relationship to the environment. Our investigation shows that periphytic protozoa in the Niyang River contained 15 genera, belonged to Tubulinea, Alveolata, Discosea and Rhizaria, Alveolata possessed most genera, up to nine, with highest share in abundance, exceeding 50%, Difflugia and Glaucoma were dominant genera. Moreover, four diversity indices of periphytic protozoa, including species richness, total abundance, Shannon-Wiener diversity index and Pielou＇s evenness index, displayed a significant descending trend as the seasons continued, in the order of winter, spring, summer and autumn; with a significant difference existing between winter and summer （or autumn） for Shannon-Wiener diversity index and species richness （P〈0.05）. Four of these diversity indices also presented a V-shaped pattern between the upper middle course of the Niyang River and the confluence of the Niyang River and Yarlung Zangbo River, with the lowest value occurred in the middle course of the Niyang River. However, no significant variation was found through the Niyang River （P〉0.05）. In addition, canonical correlation analysis （CCA） shows that the densities of Difflugia, Glaucomais, Enchelydium, Cyphoderia, and Enchelys correlate with water temperature, alkalinity, hardness, pH, and dissolved oxygen, respectively. Lastly, the relationship between periphytic protozoa diversity and the environmental factors of the Niyang River can be predicted using classification and regression trees （CART） annalysis, which suggests that the total abundance and Shannon-Wiener diversity index would be higher when the elevation is above 3 308 m. On the other hand, the Shannon-Wiener diversity index and Pielou＇s evenness index would be lower when pH and ammoniacal nitrogen have lower or higher values. Finally yet importantly, close attention should be paid to periphytic protozoa and its environment to ensure sustainable development of the Niyang River ecosystem.

Effect of Irrigation and Rainfall on Water Consumption Characteristics and Yield of High Yield Highland Barley in Tibet River Valley

This paper was to study the effect of irrigation and rainfall on water consumption characteristics and yield of high yield highland barley in Tibet river valley.In pots, highland barley-25 of Tibet was used as the test material to provide eight water stress treatments： normal water, slight water stress, middle water stress, and severe water stress in two environmental conditions（the whole growth period water stress and the rainwater irrigation after filling stage）. Test results indicated that water consumption increased with soil water rise. The maximum consumption of water was at the joining stage and filling stage. And then, the results showed that under rainwater irrigation treatment, the more the soil moisture was, the more the water consumption was. The water stress in whole highland barely growth period reduced biomass and yield. Compared with that of normal water treatment, biomass of slight water stress, middle water stress and severe water stress treatment was decreased by 29.9%, 41.7% and 47.6%, respectively, and yield of the three treatments was decreased by 15.8%, 43.7% and 57.2%, respectively. But rainfall after filling stage was beneficial to biomass and yield of highland barely. Compared with water stress on whole growth period, the biomass and yield of rainfall treatments after the filling stage were increased by 13%, 75.8%, 128.1%, 157.8% and 42.8%, 84%, 201.6%,and 269.5%. The results indicated that biomass and yield of rainwater irrigation after the filling stage had compensatory effect for highland barley growth under water stress, and could improve the water use efficiency. Therefore, properly rainwater usage is beneficial to the increase of yield and water use efficiency of Tibet highland barley-25 under water stress.

Distribution patterns of benthic diatoms during summer in the Niyang River,Tibet,China

The aim of this study was to investigate the distribution, density, community structure and biodiversity characteristics of benthic diatoms, and to analyze whether differences in species composition and abundance exist in different regions of the Niyang River, Tibet. Among the 157 taxa observed in 15 sampling sites in the main river and tributary, most were casual species （〉100）, the relative abundance of the genera Achnantkes and Fragilaria was 67% of the total relative abundance. Acknantkes minutissima was the most important species and dominated the whole river reaches （average relative abundance was 30%）; the average diatom densities were 7.4 x 105 cell/cm2 at all sites, and increased slowly from the upper section to downriver. The significant indicator taxa with higher relative abundance were Achnanthes biasolettiana （18.0%） and Fragilaria arcus （18.2%）, Fragilaria capucina var. vaucheriae （31.2%）, Fragilaria construens var. renter （11.3%） and Cymbella affinis （11.0%） in the upper, tributary and mid-river sections, respectively. Achnanthes minutissima was the most abundant species （56%） in the downriver section. Biodiversity indices showed a gradual decrease from the up- to down-river section, and dominant species were more abundant in the upper and mid-river sections than in the downriver section. A two-way indictor species analysis （TWINSPAN） of diatom composition clearly showed four different groups, namely the upper, mid, lower and tributary sections. Detrended correspondence analysis （DCA） supported the results of TW1NSPAN, and the characteristics of site distribution and species composition in the Niyang River supported the spatial structure of diatom assemblages. This study indicates that bio-assessment programs utilizing benthic diatoms could clearly benefit lotic water with regional stratification.