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刘文典的骨鲠、狂慢与刻薄
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作者 孙克诚 《民主与科学》 2015年第2期66-68,共3页
中国现代史上一批学人、大师中我行我素个性鲜明者甚多,留下许多逸闻趣事,令人闻知解颐启颜、瞠目结舌。其中最使人难忘者当属国学大师刘文典,其性格之骨鲠、狂慢与刻薄,一二事例中可见,于今仍启人深思。据云,蒋介石掌握军政大权后,多... 中国现代史上一批学人、大师中我行我素个性鲜明者甚多,留下许多逸闻趣事,令人闻知解颐启颜、瞠目结舌。其中最使人难忘者当属国学大师刘文典,其性格之骨鲠、狂慢与刻薄,一二事例中可见,于今仍启人深思。据云,蒋介石掌握军政大权后,多次表示要到新成立的安徽大学视察,校长刘文典总是婉拒蒋到校"训话"。后来虽勉强同意,但蒋到校视察时。 展开更多
关键词 刘文典 逸闻趣事 中国现代史 安徽大学 人物春秋 林流 令人 田长霖 性格悲剧 徐世昌
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Correlations Between Plant Biomass and Soil Respiration in a Leymus chinensis Community in the Xilin River Basin of Inner Mongolia 被引量:13
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作者 李凌浩 韩兴国 +7 位作者 王其兵 陈全胜 张焱 杨晶 闫志丹 李鑫 白文明 宋世环 《Acta Botanica Sinica》 CSCD 2002年第5期593-597,共5页
This paper reports on two years of measurement of soil respiration and canopy-root biomass in a Leymus chinensis community in the Xilin River basin of Inner Mongolia. Correlations between components of plant biomass a... This paper reports on two years of measurement of soil respiration and canopy-root biomass in a Leymus chinensis community in the Xilin River basin of Inner Mongolia. Correlations between components of plant biomass and soil respiration rates were examined. From respiration data based on CO2 uptake by NaOH and corresponding root biomass values for each run of 10 plots, a linear regression of CO2 evolution rates on root dry weights has been achieved for every ten days. By applying the approach of extrapolating the regressive line to zero root biomass, the proportion of the total soil respiration flux that is attributable to live root respiration was estimated to be about 27% on average, ranging from 14% to 39% in the growing season in 1998. There were no evident relations between the total canopy biomass or root biomass and CO2 evolution rates, but a significant exponential relation did exist between tire live-canopy biomass and CO2 evolution rates. 展开更多
关键词 root respiration total soil respiration temperate grassland plant biomass
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Review of forest ecology studies in China 被引量:3
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作者 王庆礼 邓红兵 +1 位作者 王绍先 李杨 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第3期231-234,252,共4页
As the most important type or component in the terrestrial ecosystems, forest ecosystem makes its role obviously prominent and important on environment and human being. It possesses non-substitutable functions in the ... As the most important type or component in the terrestrial ecosystems, forest ecosystem makes its role obviously prominent and important on environment and human being. It possesses non-substitutable functions in the process of sustainable development. However, due to the complexity of the forest ecosystem and the relatively delay or lack of the related research technology, the science is still in the case of immature and questions. This paper summarized and reviewed briefly the development and the present case of the forest ecology, then pointed out the existing problems in the forest ecosystem researches. In the end, we discussed several fields that need to pay more attention to in future researches. 展开更多
关键词 FOREST ECOSYSTEM Forest ecology Structure and function MANAGEMENT HEALTH WATERSHED
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Radial Variation in Sap Flux Density as a Function of Sapwood Thickness in Two Eucalyptus ( Eucalyptus urophylla ) Plantations 被引量:9
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作者 周国逸 黄志宏 +4 位作者 Jim MORRIS 李志安 John COLLOPY 张宁南 白嘉雨 《Acta Botanica Sinica》 CSCD 2002年第12期1418-1424,共7页
Radial variation in sap flux density (SFD) as a function of sapwood thickness is of importance in accurately estimating sap flux through sapwood area which, in turn, decides the precision of heat pulse application. Ho... Radial variation in sap flux density (SFD) as a function of sapwood thickness is of importance in accurately estimating sap flux through sapwood area which, in turn, decides the precision of heat pulse application. However, until now, only a few studies have evaluated the magnitude and significance of sampling errors associated with radial gradients in SFD, which were based on the small monitoring measurement data from a few trees. Based on one year of heat pulse observation of two 3 - 4 years old Eucalyptus urophylla S. T.,P Blake plantations in Leizhou Peninsula, Guangdong Province, China, a way of data processing was developed to treat with the lots of SFD data measured from 39 trees. It was found that the radial variation in SFD as a function of sapwood thickness in the two eucalyptus plantation sites could be expressed as y = 3. 667 5x(3) - 7.295 5x(2) + 3.682 6x + 0. 567 4 (R-2 = 0. 939 1, n = 80, P = 0.01), where y is the ratio of SFD of a sensor to the average of four data in different depths, x is the ratio of a sensor depth to tire radial sapwood thickness. It was the same (as in the following equation) in Jijia site, y = 5.006 2x(3) - 9.116 1x(2) + 4. 454 4x + 0.463 4 (R-2 = 0. 806 9, n = 72, P = 0.01) in Hetou site. From cambium to heartwood, SFD showed some increases at first and then decreases continuously. However, because die trees were very young, the maximum SFD was only 0. 33 - 0. 36 times more than the minimum. 展开更多
关键词 radial variation sap flux density sapwood thickness eucalyptus trees
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Variation of Water-Use Efficiency of Leymus chinensis and Cleistogenes squarrosa in Different Plant Communities in Xilin River Basin, Nei Mongol 被引量:6
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作者 陈世苹 白永飞 韩兴国 《Acta Botanica Sinica》 CSCD 2002年第12期1484-1490,共7页
Water is usually considered to be a key limiting factor for the growth and reproduction of steppe plants in the Xilin River Basin, Nei Mongol. Foliar delta C-13 values, an indicator of long-term intercellular carbon d... Water is usually considered to be a key limiting factor for the growth and reproduction of steppe plants in the Xilin River Basin, Nei Mongol. Foliar delta C-13 values, an indicator of long-term intercellular carbon dioxide concentration and thus of water-use efficiency (WUE) in plants, were measured on Leymus chinensis (Trin.) Tzvel. and Cleistogenes squarrosa (Trin.) Keng. in six communities of different habitats in die Xilin River Basin. The foliar delta C-13 values of both species tended to increase with decreasing soil water content (SWC) and a significant negative correlation was found between foliar delta C-13 Values and SWC in different soil layers, indicating that the two species could change WUE according to water availability. We also found relatively constant leaf water contents (LWC) of the two species in different habitats. Our results implied that the two steppe species might have adapted to different soil water regimes either through adjusting stomatal conductance to get a proper WUE, or through enhancing the osmosis-regulating ability to keep a relatively stable LWC. Our findings could partially explain why the two plant species have a wide distribution range and become dominant in the Xilin River Basin. 展开更多
关键词 Xilin River Basin Leymus chinensis Cleistogenes squarrosa water-use efficiency delta C-13 value
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Turbulence regime near the forest floor of a mixed broad leaved/Korean pine forest in Changbai Mountains 被引量:5
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作者 张军辉 丁之慧 +2 位作者 韩士杰 邹春静 周玉梅 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第2期119-122,164,共4页
The measurement and observation for this study were carried out by using a three-dimensional (u, v, w) Sonic anemometer (IAP-SA 485), at Forest Ecosystem Opened Research Station of Changbai Mountains (12828扙 and 4224... The measurement and observation for this study were carried out by using a three-dimensional (u, v, w) Sonic anemometer (IAP-SA 485), at Forest Ecosystem Opened Research Station of Changbai Mountains (12828扙 and 4224?N, Jilin Province, P. R. China) in August 2001. The basic characteristics of turbulence, such as turbulence intensity, atmospheric stability, time scales, and convection state, near the forest floor were analyzed. It is concluded that the airflow near forest floor is characterized by high intermittence and asymmetry, and the active and upward movement takes the leading position. Near forest floor, the vertical turbulence is retained and its time scale and length scale are much less than that of u, v components. The eddy near forest floor shows a flat structure and look like a ’Disk’. Buoyancy plays a leading role in the generation and maintenance of local turbulence 展开更多
关键词 Forest floor Velocity statistics Atmospheric stability Convection states
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Dynamics of Slope Runoff and Soil Erosion of Different Forest Types in Karst Depression 被引量:6
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作者 张喜 连宾 +2 位作者 尹洁 吴永波 崔迎春 《Agricultural Science & Technology》 CAS 2010年第3期166-171,共6页
[Objective] The research was aimed to study the dynamics of slope runoff and soil erosion in different forest types in karst depression.[Method] Precipitation observation sites at the bottom of karst depression and ru... [Objective] The research was aimed to study the dynamics of slope runoff and soil erosion in different forest types in karst depression.[Method] Precipitation observation sites at the bottom of karst depression and runoff observation sites in different forest types were established to monitor regularly the main indices changes of runoff and soil erosion at fixed position in 4 years.[Result] The surface runoff of different forest types appeared singer peak from February to November,with lowest valley from June to July.The runoff coefficient appeared double peaks from February to May and from July to September.The changing coefficient of runoff appeared three peaks from March to April,from July to August and from September to November.The silt concentration appeared one peak from March to May and The erosion modulus appeared double peaks from March to May and from June to August.Runoff showed annually reduced trend with the growth of forests and the development of vegetation layer's structure.There was a positive correlation between the runoff and its silt concentration in different forest types.Precipitation and evaporation had notable positive correlation with the runoff,and similar correlation but not marked with silt concentration.The fitting analysis results of surface runoff and erosion modulus showed that rocky desertification intensified the unevenness of surface runoff and increased the surface runoff and erosion modulus.The penetrability of surface soil in new planted forest was lower than that in young forest,and that in surface soil of different forest types was higher than in bottom soil.[Conclusion] The research provided theoretical basis for the biological management technologies of water and soil conservation and the control of karst rocky desertification in karst regions. 展开更多
关键词 Karst depression Forest types RUNOFF Erosion modulus Affecting factors
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The runoff characteristics and harmonic analysis of the soil moisture dynamics in Robinia pseudoacacia stand 被引量:1
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作者 高鹏 刘作新 陈伏生 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第4期295-298,共4页
Robinia pseudoacacia stands act as a typical ecological protection forest in hilly semi-arid area of China. Two fields of surface runoff were separately set up in R. pseudoacacia stand and its clearcut area in the wes... Robinia pseudoacacia stands act as a typical ecological protection forest in hilly semi-arid area of China. Two fields of surface runoff were separately set up in R. pseudoacacia stand and its clearcut area in the western Liaoning Province (1850-12225 E, 4024-4234 N) for measuring the characteristics of runoff and sediment as well as soil moisture dynamics. Contractive analysis of the two land types showed that there existed a significant difference in volumes of runoff and sediment between the sites of R. pseudoacacia stand and its clearcut area. The runoff volume and sediment volume in clearcut area were much bigger than those in R. pseudoacacia stand, with an increase amount of 40%-177% for runoff and 180%-400% for sediment. Hydrograph of surface runoff of typical rainfall showed that the peak value of runoff in R. pseudoacacia stand was decreased by 1.0-2.5?0-3m3s-1 compared with that in its clearcut area, and the occurring time of peak value of runoff in R. pseudoacacia stand was 10-20 min later than that in its clearcut area. Harmonic analysis of soil moisture dynamics indicated that the soil moisture in R. pseudoacacia stand was 2.3 % higher than that in clearcut area, and the soil moisture both in R. pseudoacacia stand and its clearcut area could be divided into dry season and humid season and varied periodically with annual rainfall precipitation. It was concluded that R. pseudoacacia stand plays a very important role in storing water, increasing soil moisture, and reducing surface runoff and soil erosion. 展开更多
关键词 Hilly semi-arid area Robinia pseudoacacia stand Runoff generation characteristics Soil moisture dynamics Harmonic analysis
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Concentration variations of several ions in stream after a wildfire
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作者 刘洋 胡海清 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第4期319-321,共3页
In May 2006, a high intensity wildfire occurred in Songling forest region in Daxing'an Mountains, China. The concentration changes of eight ions (K^+, Na^+, Ca^2+, Mg^2+, Cl^-, Br^-, NO3^- and SO4^2-) were meas... In May 2006, a high intensity wildfire occurred in Songling forest region in Daxing'an Mountains, China. The concentration changes of eight ions (K^+, Na^+, Ca^2+, Mg^2+, Cl^-, Br^-, NO3^- and SO4^2-) were measured in burned and tmbumed streams after fire from May to Oct., 2006. Results show that the most ions flux were higher in burned stream than that in unburned stream during the sampling period, and the greatest concentrations of most ions transported from burned stream occurred in July. After fire, the most amplitude chemical ion was Ca^2+, whose average concentration was 5.50 mg·L^-1 higher than that in unburned stream, and the total concentration of every chemical ion presents a trend Ca^2+〉SO4^2- 〉Na^+〉Mg^2+〉NO3^- . The average concentrations of Ca^2+, SO4^2- , Na^+'Mg^2+,NO3^- showed an increase trend, but those of K^+, Cl^- , Br had a decreased trend. SO4^2- had the largest loss among these anions, followed by NO3^-. Overall, the increase degree of cation was greater than that of anion after burning. 展开更多
关键词 Forest fire STREAM Water quality NUTRIENTS Fire effect
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迎风展翅
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作者 莱瑞.亨雷 杰夫.希尔巴 《电影评介》 北大核心 2000年第12期57-57,共1页
关键词 万加 SHINE 八子 林流 气户 冰寒 解子 雨川
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Comparison of Soil Respiration in Two Grass-Dominated Communitiesin the Xil in River Basin: Correlations and Controls 被引量:5
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作者 张焱 李凌浩 +5 位作者 王艳芬 唐芳 陈全胜 杨晶 袁志友 董云社 《Acta Botanica Sinica》 CSCD 2003年第9期1024-1029,共6页
A comparative study of soil respiration was conducted between in a semi-arid steppe community and in a wet meadow community in the Xilin River Basin of Nei Mongol. The seasonal pattern, the climatic controls, and the ... A comparative study of soil respiration was conducted between in a semi-arid steppe community and in a wet meadow community in the Xilin River Basin of Nei Mongol. The seasonal pattern, the climatic controls, and the correlations of soil respiration with plant biomass components, were examined for each community. The main results are reported as follows: (1) The seasonal changes in soil respiration in the two communities had similar dynamic patterns (both being of two peaks), ranging from 312.8 to 1738.9 mg C(.)m(-2).s(-1) and from 354.6 to 2235.6 Mg C.m(-2).s(-1) in the growing season for the steppe plot and the meadow plot respectively. The soil respiration rate of the meadow plot was distinctly higher than that of the steppe plot, with the daily averages being 1349.6 mg C-m(-2).s(-1) and 785.9 mg C-m(-2).s(-1) respectively. (2) The correlation between soil respiration rate and soil moisture was much more significant than with temperature for the steppe community, and being on the contrary for the meadow community, reflecting the different effects of the two climatic factors in different habitats. Based on these regressive relations, the total CO2 efflux rate in the growing season in 2001 was estimated as 142.4 g C/m(2) in the steppe plot, and 236.1 g C/m(2) in the meadow plot. (3) There was no evident relation between the total canopy biomass and CO2 evolution rate, but a significant power function relation between the live canopy biomass and CO2 evolution rate in the meadow plot was detected. In the steppe plot, there existed only a weak relation between soil respiration and either live or total canopy biomass. 展开更多
关键词 soil respiration temperature soil moisture canopy biomass STEPPE MEADOW
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Biomass, litterfall and the nutrient fluxes in Chinese fir stands of different age in subtropical China 被引量:18
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作者 马祥庆 刘春江 +2 位作者 Ilvesniemi Hannu Carl J.Westman 刘爱琴 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第3期165-170,250,共6页
Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.), a fast-growing, ever-green conifer tree with high yield and excellent quality, is the most important tree species of timber plantations in subtropical China. We inv... Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.), a fast-growing, ever-green conifer tree with high yield and excellent quality, is the most important tree species of timber plantations in subtropical China. We investigated the characteristics of biomass, litterfall and nutrient fluxes in the 8, 14 and 24 year-old stands, representing the young, middle-aged and mature stands. The results showed that Chinese fir plantations in central Fujian province had high productivity, and the proportion of stem mass in total biomass was between 50%-70%. Chinese fir was low nutrient-return tree species with litterfall. Nutrient withdrawal from senescing needles was a strong age-dependence for nitrogen, phosphorous and potassium in Chinese fir. With a management system of such short-rotation and continuously pure-crop planting, harvesting timber can lead to great nutrient loss, which may be one of the causes for site degradation. 展开更多
关键词 Chinese fir BIOMASS PRODUCTIVITY Litter fall Nutrient flux
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这种说法欠妥
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作者 滕明可 胡永华 《小学教学研究》 1994年第9期16-17,共2页
六年制小学语文课本第十一册的基础训练6中的第三题“……仿照后面的三个句子,各说一句打比方的话”此题共五个比喻句,其中第五句:“敌人使用了燃烧弹,邱少云的周围成了一片火海。”(十一册《我的战友邱少云》)笔者认为不是比喻句。众... 六年制小学语文课本第十一册的基础训练6中的第三题“……仿照后面的三个句子,各说一句打比方的话”此题共五个比喻句,其中第五句:“敌人使用了燃烧弹,邱少云的周围成了一片火海。”(十一册《我的战友邱少云》)笔者认为不是比喻句。众所周知,所谓“比喻”就是“说明或者形容某种事物,可以不直接描述这种事物的情形, 展开更多
关键词 语文课本 邱少云 喻句 基础训练 比喻词 组织纪律性 教学参考书 林流 《现代汉语》 玉米棒子
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Carbon Sink Effects in Conversion of Farmland to Forest Project in Karst Drainage Basin——A Case of Hongfenghu Drainage Basin in Guizhou Province 被引量:1
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作者 焦树林 艾其帅 《Agricultural Science & Technology》 CAS 2011年第8期1174-1178,共5页
[Objective]Study on carbon sink effects in Conversion of Farmland to Forest Project in Hongfenghu drainage basin in order to provide evidences for assessing carbon sink potential of conversion of farmland to forest in... [Objective]Study on carbon sink effects in Conversion of Farmland to Forest Project in Hongfenghu drainage basin in order to provide evidences for assessing carbon sink potential of conversion of farmland to forest in Guizhou Province.[Method]By investigating the implement of Conversion of Farmland to Forest Project in Hongfenghu drainage basin from 2000 to 2006,the carbon sink amount and effect of seven main tree species in the foreat region like Cunninghamia lanceolata,Cryptomeria fortunei,Amygdalus persica,Prunus salicina,Armeniaca vulgaris,Camptotheca acuminate and Catalpa bungei were calculated,based on which the amount of forest carbon sinks in Hongfenghu drainage basin in 2015 was estimated.[Result]Biomass storage and carbon sink amount in middle and young aged forests were increasing over time from 2000 to 2006,which reached 1.05×107 kg by 2006 and would engage more and more potential.Cunninghamia lanceolata has the superior carbon sink capacity in the seven tree species in the research region,of which the amount of carbon sink per unit area will be 106.51 t/hm2 by 2015,followed by Cryptomeria fortunei with the amount of carbon sink per unit area by 99.42 t/hm2.Armeniaca vulgaris has the weakest carbon sink capacity of all the seven species with the amount of 13.03 t/hm2.The total amount of carbon sink in seven tree species was 2.35×107 kg,while the average amount of carbon sink per unit area was 26.17 t/hm2,which could produced economic benefit of 7.17×106 yuan calculated on the price of 305.0 yuan/t or 5.91×106 yuan calculated on the price of 254.1 yuan/t.[Conclusion]Economic benefits of carbon sink effects of Conversion of Farmland to Forest Project in Hongfenghu drainage basin were great with huge appreciation potential. 展开更多
关键词 Conversion of farmland to forest Amount of carbon sink Economic benefits Hongfenghu Drainage basin
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Decomposition patterns of leaf litter of seven common canopy species in a subtropical forest: dynamics of mineral nutrients 被引量:12
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作者 XU Xiao-niu Hideaki SHIBATA Tsutomu ENOKI 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第1期1-6,共6页
Dynamical patterns of mineral elements during decomposition processes were investigated for seven common canopy species in a subtropical evergreen broad-leaved forest by means of litterbag technique over 2 years. The ... Dynamical patterns of mineral elements during decomposition processes were investigated for seven common canopy species in a subtropical evergreen broad-leaved forest by means of litterbag technique over 2 years. The species studied are representative for the vegetation in the study area and differed significantly in chemical qualities of their litter. No significant relationships were found between decomposition rate (percentage dry mass remaining and decomposition constant k) and initial element cuncentrations.However, there were significant correlations betweeu the percentage of dry mass remaining and the mineral element concentrations in the remaining litter for most cases. The rank of the element mobility in decomposition process was as follows: Na = K 〉 Mg ≥ Ca 〉 N ≥ Mn ≥ Zn ≥ P 〉 Cu 〉〉 Al 〉〉 Fe. Concentrations of K and Na decreased in all species as decomposition proceeded. Calcium and Mg also decreased in concentrntion but with a temporal increase in the initial phase of decomposition, while the concentrations of other elements (Zn, Cu, AL and Fei increased for all species with exception of Mn which revealed a different pattern in different species. In most species, microelements (Cu, Al, and Fe) significantly increased in absolute amounts at the end of the litterbag incubation, which could be ascribed to a lange extent to the mechanism of abiotic fixation to humic substances rather than biological immobilization. 展开更多
关键词 Canopy species Element release Litter decomposition Litterbag experiment Microelement Evergreen broad-leaved forest
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Impact of Climate Change and Deforestation on Stream Discharge and Sediment Yield in Phu Luong Watershed, Viet Nam 被引量:3
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作者 D.B. Phan C.C. Wu S.C. Hsieh 《Journal of Environmental Science and Engineering》 2011年第8期1063-1072,共10页
The purpose of this paper is to apply "Soil and Water Assessment Tool (SWAT)" model to assess the impacts of climate change and deforestation on stream discharge and sediment yield from Phu Luong watershed in Nort... The purpose of this paper is to apply "Soil and Water Assessment Tool (SWAT)" model to assess the impacts of climate change and deforestation on stream discharge and sediment yield from Phu Luong watershed in Northern Viet Nam. Among the three climate change scenarios B 1, B2, and A2, representing low, medium, and high levels of greenhouse gas emission, respectively were set up for Viet Nam, the B2 scenario was selected for this study. Two land use scenarios (S1-2030 and $2-2050) were formulated combination with climate change in WSAT simulation. In B2 climate change scenario, mean temperature increases 0.7℃(2030) and 1.3 ℃ (2050); annual rainfall increases 2.1% (2030) and 3.80% (2050) respect to baseline scenario. The results show that the stream discharge is likely to increase in the future during the wet season with increasing threats of sedimentation. 展开更多
关键词 SWAT climate change DEFORESTATION sediment yield stream discharge
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Stable Isotopes in Precipitation in Xilin River Basin,Northern China and Their Implications 被引量:9
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作者 WU Jinkui DING Yongjian +3 位作者 YE Baisheng YANG Qiyue HOU Dianjiong XUE Liyang 《Chinese Geographical Science》 SCIE CSCD 2012年第5期531-540,共10页
Under the increasing pressure of water shortage and steppe degradation, information on the hydrological cycle in steppe region in Inner Mongolia, China is urgently needed. An intensive investigation of the temporal va... Under the increasing pressure of water shortage and steppe degradation, information on the hydrological cycle in steppe region in Inner Mongolia, China is urgently needed. An intensive investigation of the temporal varia-tions of δD and δ^18O in precipitation was conducted in 2007-2008 in the Xilin River Basin, Inner Mongolia in the northern China. The 6D and δ^18O values for 54 precipitation samples range from +1.1%o to -34.7%0 and -3.0%0 to -269%0, respectively. This wide range indicates that stable isotopes in precipitation are primarily controlled by differ-ent condensation mechanisms as a function of air temperature and varying sources of vapor. The relationship between δD and δ^18O defined a well constrained line given by δD = 7.896180 + 9.5, which is nearly identical to the Meteoric Water Line in the northern China. The temperature effect is clearly displayed in this area. The results of backward tra-jectory of each precipitation day show that the vapor of the precipitation in cold season (October to March) mainly originates from the west while the moisture source is more complicated in warm season (April to September). A light precipitation amount effect existes at the precipitation event scale in this area. The vapor source of precipitation with higher d-excesses are mainly from the west wind or neighboring inland area and precipitation with lower d-excesses from a monsoon source from the southeastern China. 展开更多
关键词 PRECIPITATION stable isotopes temporal variation Xilin River Basin
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Evaluation of small bowel blood flow in healthy subjects receiving low-dose aspirin 被引量:3
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作者 Urara Nishida Mototsugu Kato +5 位作者 Mutsumi Nishida Go Kamada Takeshi Yoshida Shouko Ono Yuichi Shimizu Masahiro Asaka 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第2期226-230,共5页
AIM:To investigate the relationship between low-dose aspirin-induced small bowel mucosal damage and blood flow,and the effect of rebamipide. METHODS:Ten healthy volunteers were enrolled in this study.The subjects were... AIM:To investigate the relationship between low-dose aspirin-induced small bowel mucosal damage and blood flow,and the effect of rebamipide. METHODS:Ten healthy volunteers were enrolled in this study.The subjects were divided into two groups:a placebo group given low-dose aspirin plus placebo and a rebamipide group given low-dose aspirin plus rebamipide for a period of 14 d.Capsule endoscopy and contrast-enhanced ultrasonography were performed before and after administration of drugs.Areas under the curves and peak value of time-intensity curve were calculated. RESULTS:Absolute differences in areas under the curves were-1102.5(95%CI:-1980.3 to-224.7,P=0.0194) in the placebo group and-152.7(95%CI:-1604.2 to 641.6,P=0.8172) in the rebamipide group. Peak values of time intensity curves were-148.0(95% CI:-269.4 to-26.2,P=0.0225) in the placebo group and 28.3(95%CI:-269.0 to 325.6,P=0.8343) in the rebamipide group.Capsule endoscopy showed mucosal breaks only in the placebo group. CONCLUSION:Short-term administration of low-dose aspirin is associated with small bowel injuries and blood flow. 展开更多
关键词 Small-intestine Capsule endoscopy Lowdose aspirin Contrast-enhanced ultrasonography REBAMIPIDE
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Effects of Terracing and Agroforestry on Soil and Water Loss in Hilly Areas of the Sichuan Basin, China 被引量:16
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作者 J.H. ZHANG Z.A. SU G.C. LIU 《Journal of Mountain Science》 SCIE CSCD 2008年第3期241-248,共8页
Soil erosion in hilly areas of the Sichuan Basin is a serious concern over sustainable crop production and sound ecosystem. A 3-year experiment was conducted using the method of runoff plots to examine the effects of ... Soil erosion in hilly areas of the Sichuan Basin is a serious concern over sustainable crop production and sound ecosystem. A 3-year experiment was conducted using the method of runoff plots to examine the effects of terracing and agroforestry in farmland systems on soil and water conservation of slope fields in the hilly areas in Jianyang County, Sichuan Province, Southwestern China. A power function (Y = aXb) can statistically describe the relationship between water runoff (Y) and rainfall (X). The regression equation for the treatment of sloping terraces with crops (Plot 2) is remarkably different from that for the treatment of sloping terraces with grasses and trees (Plot 1) and the conventional up- and down-slope crop system (Plot 3) regarding equation coefficients, while regression equations are similar between Plot 1 and Plot 3. Water runoff amount and runoff coefficient of slope fields increased by 21.5~41.0 % and 27.5~69.7 % respectively, compared to those of sloping terraces, suggesting that terracing notably reduced the water runoff in the field. In the case of sloping terraces, lower amount of water runoff was observed on sloping terraces with crops than on sloping terraces with grasses and trees. Sediment yields on the slope fields in the normal year of rainfall distribution were notably higher (34.41~331.67 % and 37.06~403.44 % for Plot 1 and Plot 2, respectively) than those on sloping terraces, implying that terracing also plays a significant role in the reduction in soil erosion. It is suggested that terracing with crops is significantly effective for soil and water conservation in cultivatedfarmland, while the conventional practice of up- and down- slope cultivation creates high rates of water runoff and soil sediment transport. Terracing with grasses and fruit trees shows a less reduction in water runoff than terracing with crops, which was observed in the 3-year experiments. 展开更多
关键词 AGROFORESTRY sediment transport RUNOFF sloping terrace soil and water conservation
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Responses of terrestrial water cycle components to afforestation within and around the Yellow River basin 被引量:3
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作者 LV Meixia MA Zhuguo PENG Shaoming 《Atmospheric and Oceanic Science Letters》 CSCD 2019年第2期116-123,共8页
Reforestation has attracted worldwide attention because of its multiple environmental benefits,but its impact on water resources is complicated and still controversial. In this study, the authors conducted numerical e... Reforestation has attracted worldwide attention because of its multiple environmental benefits,but its impact on water resources is complicated and still controversial. In this study, the authors conducted numerical experiments within and around the Yellow River basin under the Grain-forGreen project using the Weather Research and Forecasting model. The results showed that the terrestrial water cycle process was sensitive to land use/cover change in the study region. Under the increase of mixed forests within and below the basin, the basin-averaged precipitation and evaporation increased by 223.17 and 223.88 mm respectively, but the surface runoff decreased by 2.22 mm from 2006 to 2010. In other words, the forest-induced increase in evaporation exceeded that of precipitation along with decreased surface runoff. Importantly, the afforestation effects on water resources seemed to enhance with time, and the effects of the same vegetation change were different in dry and wet years with different precipitation amounts(i.e. different atmospheric circulation background). It should be noted that it is difficult to obtain one product that can explicitly reflect the spatial distribution of actual land cover change promoted by the Grain-for-Green project in the Yellow River basin, which is an important obstacle to clearly identify the reforestation impacts. A land cover dataset derived from advantages of multiple sets of data therefore needs to be proposed. 展开更多
关键词 AFFORESTATION precipitation EVAPORATION RUNOFF Yellow River basin
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