明代北水陆法会壁画图式空间表达与审美承载探究

我国现存明代水陆法会壁画是依据北水陆仪轨——《天地冥阳水陆仪文》而完成的,是典型的北水陆法会壁画。画面经营充满智慧:其突出的对称统一、绘塑合一、以"动"取"势"等审美规律在明代水陆壁画图示空间表达中起到了支撑作用;壁画审美承载具有明显的时代特征:注重世俗情怀、装饰化和程式化风格的审美传达,体现了强烈的民族化和世俗化创作倾向。

北水陆修斋仪轨续考

本文利用新材料,对敦煌文献、韩刻汉籍、日藏汉籍和散佚文献等宋代水陆文献做一分析和考释.文章认为北水陆的脉络如下:梁武帝(以《东都发愿文》为代表)、英公(水陆重兴)、杨谔《水陆仪文》、仔夔《佛说焰口经天地冥阳水陆仪文》和佚名编《天地冥阳水陆仪文》.《天地冥阳水陆仪文》在元明清三代盛极一时,到清末渐趋衰落.

山西寿阳白道普光寺水陆壁画图像考

山西寿阳白道普光寺正殿内三壁水陆壁画为明代崇祯时期作品,其神祇排列与《天地冥阳水陆仪文》上、中、下三卷内容一致,是文图互证最佳样本之一。此殿壁画在修复前曾覆白灰,导致部分榜题尽失。通过水陆仪文与永安寺水陆壁画校验,将此殿壁画神祇人物图像题记全部还原。"双重证法"的有效利用,使文献与考古在此次研究中得以充分体现。解密壁画图像,同时也是对传世的"山西本"北水陆仪文的有力证明。

河西走廊水陆画中的“无主孤魂图”略论

"无主孤魂图"是河西走廊水陆画中比较特殊的一类图像,地处河西走廊的古浪、民乐两县现藏明清水陆画中有几轴所绘内容即为"无主孤魂图"。此类图像为河西走廊民俗、宗教、社会研究的重要视觉材料,反映了明清时期河西走廊诸多民俗文化内涵。图像间多有相似粉本,在河西走廊明清水陆画中广为流传,其艺术价值与文物价值也普遍较高,近年渐受学界瞩目,成为河西文化研究中重要的视觉图像之一。

Carbon and oxygen isotope characteristics of foraminiferan from northern South China Sea sediments and their significance to late Quaternary hydrate decomposition

Carbon and oxygen isotope and dating analyses of foraminiferan in sediment cores collected from three different areas of the northern slope of the South China Sea were conducted, in order to examine the records of the gas hydrate decomposition events since the late Quaternary under the conditions of methane seepage. The results show that： 1） the δ13C values of the benthic foraminiferan Uvigerina spp. （size range of 0.25-0.35 ram） are from -0.212% to -0.021% and the δ180 values of the planktonic foraminiferan Globigerinoides ruber （size range of 0.25-0.35 ram） are from -0.311% to -0.060%; 2） three cores （ZD2, ZD3 and ZS5） from the bottom of a hole are aged for 11 814, 26 616 and 64 090 a corresponding to the early oxygen isotope stage （MIS） Ⅰ, Ⅲ and Ⅳ final period, respectively; 3） a negative-skewed layer of carbon isotope corresponds to that of MIS II （cold period）, whose degree of negative bias is -0.2%0; and 4） the δ13C compositions of foraminiferans are similar to those of the Blake Ridge and the Gulf of Mexico sediments of the late Quaternary. According to the analysis, the reasons for these results are that the studied area is a typical area of methane seep environment in the area during MIS II due to the global sea-level fall and sea pressure decrease. Gas hydrate is decomposed and released, and a large number of light carbon isotopes of methane are released into the ocean, dissolved to inorganic carbon （DIC） pool and recorded in the foraminiferan shells. A pyrite layer developed in the negative bias layers of the foraminiferans confirms that the δ13C of foraminiferans is more affected by methane and less by the reduction of marine productivity and early diagenesis. The use of foraminiferan δ13C could accurately determine late Quaternary hydrate release events and provide evidence for both reconstructing the geological history of methane release events and exploring natural gas hydrate.

EVAPOTRANSPIRATION OF LOW-LYING PRAIRIE WETLAND IN MIDDLE REACHES OF HEIHE RIVER IN NORTHWEST CHINA

Low-lying prairie wetland, which has characteristics of both grassland and wetland, has irreplaceable ecological functions in inland river basins of Northwest China. Owing to its small-scale distribution, so far, the observation and research on it are rare. The estimation of evapotranspiration is significant to ecological and environmental construction, scientific management of pasture and protection of wetland. For studying the evapotranspiration （ET） of low-lying prairie wetland in the middle reaches of the Heihe River, an inland river, in Northwest China, the automatic weather station in Linze Ecological Experimental Station of Lanzhou University （39°15′ 3″N, 100°03′ 52″ E）, Linze, Gansu Province, was selected as a case study. Based on meteorological data collected, Bowen-Ratio Energy Balance （BREB） method was used to calculate the evapotranspiration （ET） of low-lying prairie wetland. The analysis results showed that in a whole year （September 2003 -August 2004）, the total ET was 611.5mm and mean daily 1.67mm/d. The ET varied with different growing stages. In non-growing stage （NGS）, initial growing stage （IGS）, middle growing stage （MGS） and end growing stage （EGS）, the ET was 0.57, 2.01, 3.82 and 1.49mrrdd, with a percentage of total ET of 18.26%, 9.20%, 61.83% and 10.71% respectively. In March, ET began to increase. But in April, the ET increased most. After that, it increased gradually and got the maximal value in July. From then on, the ET decreased gradually. In September, the ET decreased rapidly. With the ending of growing and the freezing of soil, the ET stopped from the middle of November to February in next year. Hourly ET analysis showed that at 8：00 a.m. （during MGS at 7：00 a.m.）, the evapotranspiration began, at 13：00 p.m. got its maximal value and at 19：00 p.m. （during MGS at 20：00 p.m.）, the evapotranspiration stopped. The intensity of ET in sunny day was much larger than that in cloudy day in the same growing stage.

稷山青龙寺立佛殿水陆壁画中的华严图像考

青龙寺水陆壁画在图式结构上以东西两壁为主要表现,按照《天地冥阳水陆仪文》记载,可与壁画具体神佛地祇进行详细对照,目前发现遗存的仪文版本皆为明代所刻印,而青龙寺壁画为元代所绘,是否"北水陆"在此期间已经流行于北方地区只有通过这唯一的元代壁画考释以来验证。

重泰寺水陆壁画内容考

《天地冥阳水陆仪文》是作者考订出的散佚在佛藏外一百多年的水陆仪文,它是北水陆的修斋仪轨。经作者研究,北方地区所有水陆图像都是依据《天地冥阳水陆仪文》绘制,而重泰寺正是北水陆图像。本文拟以河北蔚县重泰寺为例,根据仪文对图像进行必要的释读,补充缺漏的榜题,对神祇分组并对明王本尊尊号进行了必要的释读。

Terrestrial water variations in the North China Plain revealed by the GRACE mission

Using eight years of time-variant gravity measurements from the GRACE gravity satellite mission, we estimate monthly terrestrial water storage variations in the North China Plain between August 2002 and August 2010. We find that during this period, the water storage is not constant but accelerate at a rate of -1.1 cm/yr over time. The study confirms that the relatively long-term trend of water storage in the North China Plain (by 13-point moving average) is consistent well with that by linear fitting. Two hydrological models, CPC and GLDAS, are adopted in calculating surface water variations, with results indicating that they agree with those of GRACE. Furthermore, rates of -0.6 cm/yr for surface water variations and -0.5 cm/yr for groundwater variations are found in the North China Plain during the study period. Decrease of rainfall and the groundwater over-exploitation are possibly the main causes for groundwater depletion in the North China Plain. The results will be helpful for better understanding climatic changes and provide reference for the management of water resources and the establishment of policies on preventing and alleviating natural hazards.

Controlling factors for gas hydrate occurrence in Shenhu area on the northern slope of the South China Sea

Temperature and pressure on seafloor of the northern slope in the South China Sea are suitable for gas hydrate formation, but bottom simulation reflector (BSR), an indication of gas hydrate occurrence, only occurred in limited areas of the slope. Drillings in the BSR-distributed area (the District S) on the northern slope of the South China Sea suggested that gas hydrate only occurred at Sites SH2, SH3, and SH7 with high saturation (up to 20%-40%), and there is no hydrate at Sites SH1 and SH5 although the distance between SH1 to SH3 is only 500m. In this paper, we investigated seafloor gradient, fault development, temperature, and pressure in the District S on the northern slope of the South China Sea to understand the possible factors con- trolling BSR distribution and gas hydrate occurrence. The District S is a structurally fractured continental slope zone and its seafloor gradient varied greatly. The BSR-occurred areas have an average gradient of 19.89×10 2 whereas the BSR-free zone has the average gradient of 10.57×10 2 . The calculated relative structural intensities from fault densities and displacements show that the BSR-distributed areas tend to occur in the areas with a moderately high structural intensity, where faults frequently developed close to the seafloor that are possibly favored for lateral migration of gases. On the basis of temperatures and pressures at drilling sites, hydrate-occurred Sites SH2, SH3, and SH7 are located within the thermodynamically stable area for methane hydrate, and hydrate-absent Sites SH1 and SH5 are out of the thermodynamically stable area for methane hydrate formation, suggesting that both BSR and the thermodynamic stability are necessary for hydrate occurrence in the subsurface.

Characteristics of land surface thermal-hydrologic processes for different regions over North China during prevailing summer monsoon period

The observation stations of Northern China are divided into three regions:the arid Northwest China,the Loess Plateau,and the cool Northeast China.The consistencies,differences,and associated mechanisms of land surface thermal-hydrologic processes among the three regions were studied based on the normalization of major variables of land surface thermal-hydrologic processes,using data collected during prevailing summer monsoon period(July and August,2008).It is shown that differences of surface thermal-hydrologic processes are remarkable among the three regions because of different impacts of summer monsoon.Especially their soil wet layers occur at different depths,and the average albedo and its diurnal variations are distinctly different.Surface net short-wave radiation in the Loess Plateau is close to that in the cool Northeast China,but its surface net long-wave radiation is close to that in the arid Northwest China.And the ratio of net radiation to global solar radiation in the cool Northeast China is higher than the other two regions,though its temperature is lower.There are obvious regional differences in the ratios of surface sensible and latent heat fluxes to net radiation for the three regions because of distinct contribution of sensible and latent heat fluxesto land surface energy balance.The three regions are markedly different in the ratio of water vapor flux to pan evaporation,but they are consistent in the ratio of water vapor flux to precipitation.These results not only indicate different influences of climate and environmental factors on land surface thermal-hydrologic processes in the three regions,but also show that summer monsoon is important in the formation and variation of the pattern of land surface thermal-hydrologic processes.

Water in peridotite xenoliths from South China

The water contents of nominally anhydrous clinopyroxene （cpx）, orthopyroxene （opx） and olivine （ol） in peridotite xenoliths hosted by Cenozoic basalts from Yingfengling, Zhangchouchun, Fujitian and Lindi, South China, were measured by Micro- FTIR. All cpx and opx grains contained a certain amount of water, which was indicated by the presence of hydroxyls in the crystal structure. The water contents （H20, ppm） of cpx and opx from peridotite xenoliths of the study areas were 293-981, 183-752, 73-586 and 51-423 ppm, and 82-471, 74-571, 53-170 and 9-135 ppm, respectively. No prominent OH absorption bands were detected for any ol grains, indicating that the water contents were below the detection limit （approximately 2 ppm）. The entire rock contents recalculated according to mineral volume proportions were 49-163, 48-168, 21-111 and 8-40 ppm, respectively. Combined with previously reported data describing the water contents of peridotite xenoliths worldwide, the results presented here suggest that water distribution in the continental lithospheric mantle is spatially heterogeneous at a global scale. The lithospheric mantle of South China is much richer in water than that of the North China Craton, and is close to that typical of off-craton localities, such as the Basin and Range Province, and Massif Central.