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Considerations in Applying the General Equilibrium Approach to Environmental Health Assessment 被引量:2
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作者 YUE WAN HONG-WEI YANG AND TOSHIHIKO MASUI 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2005年第5期356-361,共6页
There are currently two commonly used approaches to assessing economic impacts of health damage resulting from environmental pollution: human capital approach (HCA) and willingness-to-pay (WTP). WTP can be furthe... There are currently two commonly used approaches to assessing economic impacts of health damage resulting from environmental pollution: human capital approach (HCA) and willingness-to-pay (WTP). WTP can be further divided into averted expenditure approach (AEA), hedonlc wage approach (HWA), contingent valuation approach (CVA) and hedonlc price approach (HPA). A general review of the principles behind these approaches by the authors indicates that these methods are incapable of unveiling the mechanism of health impact from the point of view of national economy. On a basis of economic system, the shocks brought about by health effects of environmental pollution change the labor supply and medical expenditure, which in turn affects the level of production activity in each sector and the total final consumption pattern of the society. The general equilibrium approach within the framework of macroeconomic theory is able to estimate the health impact on national economy comprehensively and objectively. Its mechanism and applicability are discussed in detail by the authors. 展开更多
关键词 Human capital approach WILLINGNESS-TO-PAY General equilibrium approach
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Population structures and spatial patterns of two unpalatable Arisaema species(Araceae) with and without clonal reproduction in a riparian forest intensively grazed by Sika deer 被引量:1
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作者 Tetsuya K.Matsumoto Muneto Hirob +1 位作者 Yasuaki Akaji Yuko Miyazaki 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第1期155-162,共8页
General decline of understory cover can result from increased abundance of and foraging pressure by deer.But population size and degree of aggregation can increase for unpalatable understory plants that escape foragin... General decline of understory cover can result from increased abundance of and foraging pressure by deer.But population size and degree of aggregation can increase for unpalatable understory plants that escape foraging pressure.Clonal reproduction can enable unpalatable plant species to increase their population sizes while trending toward spatially aggregated distributions.However,the details of the relationship between clonal reproduction in unpalatable plants and their dynamics under intensive deer herbivory are not clear.We compared the population structures and spatial patterns of two coexisting unpalatable plant species,Arisaema ovale(with clonal reproduction)and A.peninsulae(without clonal reproduction)in a riparian forest intensively grazed by Sika deer,and examined the null hypothesis that the extent of spatial aggregation and local population size would not differ between the clonal and non-clonal Arisaema species.In a 0.36-ha plot,A.ovale had a larger population size(1087 individuals)with a higher abundance ratio of small plants(p<0.01)than A.peninsulae(84 individuals).Analyses of spatial point processes showed that both populations were spatially aggregated(p<0.05).The spatial aggregation of A.peninsulae,however,became weaker than that of A.ovale,when we excluded one dense patch originating from irregular seed dispersion.These results,excluding the aggregated distribution observed in A.peninsulae,suggested a substantial contribution of clonal reproduction to the expansion of the local A.ovale population following intensive grazing by Sika deer. 展开更多
关键词 Arisaema ovale Arisaema peninsulae Deer herbivory Spatial pattern Unpalatable plant
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Yellowing of disease? Or differentiating for adaptation? Study on Cinnamomum camphora ecotypes 被引量:1
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作者 LI Qing ZOU Chun-jing +1 位作者 XU Ying Shimizu HIDEYUKI 《Forestry Studies in China》 CAS 2010年第2期67-73,共7页
Cinnamomum camphora (L.) Presl is an evergreen broad-leaved tree of the Lauraceae family, widely distributed in the sub-tropical areas in the south of China and used as a virescent tree in urban gardens and streets ... Cinnamomum camphora (L.) Presl is an evergreen broad-leaved tree of the Lauraceae family, widely distributed in the sub-tropical areas in the south of China and used as a virescent tree in urban gardens and streets in Shanghai for its beautiful shape and intensive stress-resistance. However, yellowing of C camphora in recent years casts doubt about its significance. We believe the green-leaved and yellow-leaved C camphora might be two different ecotypes, and tentatively refer to the green-leaved C camphora as C camphora f. viridis f. nov (CCV) and the yellow-leaved as C camphora f.flavus f. nov (CCF). We studied their differences and arrived at the following conclusions: 1) compared with CCF, the area of lamina of CCV is significantly larger and the amount of chlorophyll (Chl) significantly higher; 2) the lamina and palisade tissues of CCV are significantly thicker than those of CCF, but its cuticle is significantly thinner; 3) the shape of the stomata of CCV is different from that of the CCF; the stomatal density and stomatal index of CCV are significantly lower than those of CCF. These results show that C camphora might evolve adaptive dif- ferentiation in some aspects which can be used in virescence in urban streets and gardens. 展开更多
关键词 Cinnamomum camphora ECOTYPE differentiation CHLOROPHYLL stomatal parameters
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Vertical profiles of aerodynamic size distribution for airborne particles over Yangtze River Delta
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作者 王玮 鲍林发 +7 位作者 刘红杰 岳欣 陈建华 李红 任丽红 汤大钢 Shiro Hatakeyama and Akinori Takami 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第9期2818-2824,共7页
Based on the aircraft observations in the summer of 2003, we have studied the aerodynamic size distributions of airborne particles at altitudes ranging from 400 m to 2800 m over the central and southern areas of Jiang... Based on the aircraft observations in the summer of 2003, we have studied the aerodynamic size distributions of airborne particles at altitudes ranging from 400 m to 2800 m over the central and southern areas of Jiangsu province located in Yangtse River Delta of China. The sizes of airborne particles are measured to be in a range of 0.47- 30 μm with 57 channels, and their number concentrations, surface area concentrations and mass concentrations are also measured. The results show that the concentrations of airborne particles are very low above an altitude of 2000 m and the size distributions present a specific multi-peak mode by using insufficient samples. Below 1000 m, however, the concentrations of particles increase obviously, and their size distribution is similar to that at the ground level. The study also indicates that the concentrations, size distributions and median diameters of airborne particles above and below the boundary layer are very different, displaying different pollution features. Meanwhile, the results also show that the pollution level of airborne particles has a descending tendency with altitude increasing. 展开更多
关键词 airborne particles aerodynamic size distribution aircraft observation Yangtse River Delta
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Vegetation Formation in Estuarine Tidal Flats: Influences of Basin Scale and River-Crossing Structures of the Eight Rivers of Ise Bay in Mie and Aichi Prefectures, Japan
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作者 Korehisa Kaneko Seiich Nohara 《Open Journal of Ecology》 2014年第15期974-988,共15页
In this study, we examined the influences of the differences in basin scale and river-crossing structures of 8 rivers of Ise Bay in Mie and Aichi Prefectures, Japan on the vegetation in the estuarine tidal flats of th... In this study, we examined the influences of the differences in basin scale and river-crossing structures of 8 rivers of Ise Bay in Mie and Aichi Prefectures, Japan on the vegetation in the estuarine tidal flats of these rivers. The dominant plant communities of the estuarine tidal flats formed from rivers of large-scale river basins (exceeding 300 km2) were determined. In the Miya River, the dominant plant community was the Suaeda maritima and Artemisia fukudo community. In the Kushida River, the dominant plant community was composed of Phacelurus latifolius, Artemisia fukudo, Phragmites australis, and bamboo. In the Kumozu River, the dominant community was composed of the coastal plants Calystegia soldanella, Lathyrus japonicus, and Carex pumila and the exotic plant of Lolium multiflorum. The plant community of Suzuka River was dominated by the exotic plant of Eragrostis curvula. Among the estuarine tidal flats influenced by a small-scale river basin (50 km2 or less), the plant community of Shinbori River (Fukue tidal flat) was dominated by Suaeda maritima, and the plant communities of the Shio and Harai Rivers were dominated by Phragmites australis. The plant community of Tanaka River was dominated by Phragmites australis and coastal plants. Regarding the relationship between the vegetation and the river environment for each study site, we hypothesised that in a large basin area with few structures crossing the river, the river water catchment in the estuary after heavy rains caused large areas of disturbance and formed bare land, providing suitable habitat for an annual salt marsh plant community. In contrast, in cases with many structures crossing the river, a stable channel, an excavated riverbed and the suppression of runoff and the resulting disturbance of the estuary, flooding did not occur during high tide. Moreover, we hypothesised that in a small basin with many structures crossing the river, disturbance to the estuary was not likely, and the perennial salt marsh plant community of Phragmites australis would be widely distributed, except for a river type such as the Shinbori River, in which tide and river flow were managed by a final closure. 展开更多
关键词 Annual SALT MARSH PLANT Perennial SALT MARSH PLANT RIVER-CROSSING Structure Water Level River Basin
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-lyperspectral Response: Key for Mapping Coral Rubber, .ive and Dead Corals
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作者 Nurjannah Nurdin Teruhisa Komatsu +3 位作者 Hiroya Yamano Gulam Arafat Chair Rani Awaludin Noer 《Journal of Shipping and Ocean Engineering》 2012年第3期182-190,共9页
关键词 遥感测绘 珊瑚 橡胶 教育学院 底栖生物群落 香港 光谱响应 宏观藻类
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全球植被叶面积指数对温度和降水的响应研究 被引量:56
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作者 张佳华 符淙斌 +2 位作者 延晓冬 Seita Emori Hiroshi Kanzawa 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2002年第5期631-637,T001,T002,共9页
利用一套新的遥感信息反演的叶面积指数 (LAI)数据和生物气候数据 ,建立了全球尺度的LAI与降水及温度的总体相关和距平相关 ,用以揭示全球尺度的植被季节和年际的变化对气候变化的响应特征 .结果发现 ,全球尺度植被与气候因子的季节和... 利用一套新的遥感信息反演的叶面积指数 (LAI)数据和生物气候数据 ,建立了全球尺度的LAI与降水及温度的总体相关和距平相关 ,用以揭示全球尺度的植被季节和年际的变化对气候变化的响应特征 .结果发现 ,全球尺度植被与气候因子的季节和年际变化随不同的生态系统差异明显 .植被LAI与温度的总体正相关的最大值出现在北半球的中高纬度地区 ;LAI与降水的总体正相关高值 ( >0 .78)出现在亚洲东部、北美洲北部腹地和热带非洲北部的Sahel地区 ;最大的LAI与温度的正距平相关 ( 0 .4— 0 .6)出现在东南亚南部、非洲Sahel地区的南部和巴西东部等热带地区 ;而从LAI与降水的距平相关来看 ,最明显的特征是出现在西伯利亚、亚洲北部和北美西北部的强的负距平相关 .本文进一步阐明了出现相关特征差异的陆 展开更多
关键词 叶面积指数 降雨 温度 整体相关 距平相关 遥感信息 生物气候数据
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熊蜂气管内寄生螨布赫纳蝗螨的生物学特性观察 被引量:2
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作者 廖思米 耿金虎 +4 位作者 徐希莲 王凤鹤 周祖基 YONEDA Misaho GOKA Koichi 《昆虫学报》 CAS CSCD 北大核心 2007年第10期1083-1086,共4页
对新疆与河北地区野生明亮熊蜂及小峰熊蜂蜂王内寄生螨布赫纳蝗螨Locustacarus buchneri的生物学特性进行了初步观察。结果表明:该螨对两种熊蜂的寄生率分别为10.43%和8.3%,寄生部位为气管与气囊。室内饲养至30天的蜂王体内寄生螨量明... 对新疆与河北地区野生明亮熊蜂及小峰熊蜂蜂王内寄生螨布赫纳蝗螨Locustacarus buchneri的生物学特性进行了初步观察。结果表明:该螨对两种熊蜂的寄生率分别为10.43%和8.3%,寄生部位为气管与气囊。室内饲养至30天的蜂王体内寄生螨量明显高于饲养至60天的蜂王。未被螨寄生的蜂王与被寄生者比较,前者体重显著高于后者,但二者间产卵始期、产卵率、食卵率和存活率差异不显著。 展开更多
关键词 气管内寄生螨 布赫纳蝗螨 明亮熊蜂 小峰熊蜂 生物学特性
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利用ASTER数据估算2002年4月阿克苏地表特征和植被参数 被引量:3
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作者 马伟强 马耀明 +6 位作者 T.Matsunaga 胡泽勇 仲雷 李茂善 赵逸舟 王永杰 王介民 《高原气象》 CSCD 北大核心 2008年第3期544-550,共7页
利用ASTER卫星可见光和短波红外波段数据,估算了2002年4月12日阿克苏地区地表特征参数(地表温度T、地表反射率α)和植被参数(归一化植被指数NDVI、修正的土壤调整植被指数MSA-VI、植被覆盖度Pv和叶面积指数LAI等)。结果表明,各种植被参... 利用ASTER卫星可见光和短波红外波段数据,估算了2002年4月12日阿克苏地区地表特征参数(地表温度T、地表反射率α)和植被参数(归一化植被指数NDVI、修正的土壤调整植被指数MSA-VI、植被覆盖度Pv和叶面积指数LAI等)。结果表明,各种植被参数在沙漠地区较小,而在绿洲中的值较大。同时本文认为ASTER遥感数据有较高的地面分辨率,利用它可以更好地反映地表的植被参数及地表特征参数状况;还指出了ASTER卫星数据在沙漠绿洲中的适用性。 展开更多
关键词 阿克苏地区 ASTER 植被参数
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全球气候变化对中国未来地表径流的影响 被引量:29
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作者 游松财 Kiyoshi Takahashi Yuzuru Matsuoka 《第四纪研究》 CAS CSCD 北大核心 2002年第2期148-157,共10页
本文应用改进的水分平衡模型研究了不同气候变化情景下中国未来地表径流的变化。结果表明 :基于不同的气候变化情景模拟所得的地表径流变化在空间上有差异 ,总体上 ,中国未来的地表径流将增加 ;长江上游地区的地表径流春季下降但在夏季... 本文应用改进的水分平衡模型研究了不同气候变化情景下中国未来地表径流的变化。结果表明 :基于不同的气候变化情景模拟所得的地表径流变化在空间上有差异 ,总体上 ,中国未来的地表径流将增加 ;长江上游地区的地表径流春季下降但在夏季增加 ,而下游地区的则相反 ,夏季径流下降而春季径流剧增 ;气溶胶对地表径流变化方面有影响 ,但在各个气候变化情景下缺乏一致性。 展开更多
关键词 气候变化 地表径流 水分平衡模型 气溶胶 人类活动
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环境污染物对着床前小鼠胚胎的DNA甲基转移酶活性的影响 被引量:3
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作者 吴庆 周志俊 大迫诚一郎 《卫生研究》 CAS CSCD 北大核心 2006年第1期30-32,共3页
目的探讨环境污染物对着床前小鼠胚胎发育的直接影响,以及对基因组DNA甲基化的影响。方法着床前小鼠1细胞期胚被放入含有不同的环境污染物的培养液中进行体外培养;观察1细胞期胚发育至胚泡期胚的发育率;测定胚泡期胚的DNA甲基转移酶(DNA... 目的探讨环境污染物对着床前小鼠胚胎发育的直接影响,以及对基因组DNA甲基化的影响。方法着床前小鼠1细胞期胚被放入含有不同的环境污染物的培养液中进行体外培养;观察1细胞期胚发育至胚泡期胚的发育率;测定胚泡期胚的DNA甲基转移酶(DNA methyltransferase)活性。结果小鼠胚胎着床前期在含有环境污染物的培养液里发育的过程中,其形态没有发生显著的异常变化,各实验组的胚胎发育率在61%~67%。然而,DNA甲基转移酶活性应环境污染物种类而异发生不同变化。与对照组相比,二英2,3,7,8tetrachlorodibenzopdioxin(TCDD)使着床前胚的DNA甲基转移酶活性显著升高;而二乙烯二苯乙烯雌酚Diethylstilbestrol(DES)和多氯联苯中的2,2′,3,3′4,4′polychlorinatedbiphenyl(PCB153)使着床前胚的DNA甲基转移酶活性显著下降。不过,二氯联苯二氯乙烯p,p′dichlorodiphenelethylene(DDE)和苯二甲酸二丁酯dibutylphthalate(DBP)对着床前胚的甲基转移酶活性的影响未达到统计显著水平。结论环境污染物可在体外培养中对着床前胚DNA甲基转移酶活性产生作用,进而可能影响基因组甲基化模式的变化。 展开更多
关键词 着床前初期胚 DNA甲基转移酶活性 环境污染物
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从营养扰动实验看原绿球藻在近海分布的制约因素(英文) 被引量:2
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作者 焦念志 杨燕辉 +2 位作者 Hiroshi KOSHIKAWA Shigeki HARADA Masataka WATANABE 《Acta Botanica Sinica》 CSCD 2002年第6期731-739,共9页
地球上细胞最小、丰度最大的放氧光合自养原核生物原绿球藻 (Prochlorococcus)发现于热带大洋 ,并被证实可在某些近海甚至近岸水域大量分布。但除温度之外 ,原绿球藻自然分布的控制因子尚不明了。从近海和大洋生态条件的主要差别考虑 ,... 地球上细胞最小、丰度最大的放氧光合自养原核生物原绿球藻 (Prochlorococcus)发现于热带大洋 ,并被证实可在某些近海甚至近岸水域大量分布。但除温度之外 ,原绿球藻自然分布的控制因子尚不明了。从近海和大洋生态条件的主要差别考虑 ,在南海进行了主要营养盐———氮、磷和微量元素———铁、钴扰动的现场培养实验 ,并应用流式细胞技术监测原绿球藻及聚球藻 (Synechococcus)、超微型真核浮游植物 (pico_eukaryotes)的细胞丰度和单细胞色素含量的响应以及细菌的影响。结果表明 ,磷和钴的添加有利于原绿球藻 ,而氮和铁的添加更有利于聚球藻和超微型真核浮游植物。同时 ,由环境条件引起的生物响应又间接地导致超微型生物之间的相互作用。因而 ,原绿球藻在近海的分布 。 展开更多
关键词 原绿球藻 超微型浮游生物 营养盐 南海
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纤维素降解菌在高温厌氧消化过程中的作用 被引量:1
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作者 K. Syutsubo Y. Nagaya +2 位作者 S. Sakai A. Miya 张敏 《中国沼气》 2009年第5期18-20,共3页
前期研究表明梭菌属的新株JC3(Clostridiumsp.Strain JC3)是嗜热产甲烷污泥中的主要纤维素降解菌。本项目采用分子生物学技术定量研究了菌株JC3在高温厌氧消化过程中的作用。在含三个小室(室1,室2,室3)的厌氧折流板反应器(9.5 L)中进行... 前期研究表明梭菌属的新株JC3(Clostridiumsp.Strain JC3)是嗜热产甲烷污泥中的主要纤维素降解菌。本项目采用分子生物学技术定量研究了菌株JC3在高温厌氧消化过程中的作用。在含三个小室(室1,室2,室3)的厌氧折流板反应器(9.5 L)中进行纤维素降解实验,试验温度设为55℃。当负荷为2.5 kg COD.m-3d-1,HRT为2天时,80%以上的COD进料都转化为甲烷。采用专门针对菌株JC3的特异性荧光针来研究折流式反应器中污泥样品。结果表明JC3细胞对DAPI染色细胞的比例从低于0.5%(最低检测极限)增加到9.4%(室1),13.1%(室2)和21.6%(室3)。这表明由荧光原位杂交技术确定的菌株JC3细胞数与滞留污泥的纤维素降解产甲烷活性密切相关。设计了一个针对菌株JC3纤维素酶基因(纤维二糖水解酶A cbh A)的特异探针,并应用到处理固体废弃物如咖啡渣、废纸、垃圾和纤维素等消化污泥中,采用定量PCR技术发现菌株JC3细胞数与高温消化器中污泥的纤维素降解能力密切相关。因此,在高温厌氧消化过程中,菌株JC3对厌氧水解纤维素是非常重要的。 展开更多
关键词 纤维素 梭菌 微生物群落结构 定量种群分析 高温厌氧消化
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Evapotranspiration and Its Energy Exchange in Alpine Meadow Ecosystem on the Qinghai-Tibetan Plateau 被引量:11
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作者 LI Jie JIANG Sha +4 位作者 WANG Bin JIANG Wei-wei TANG Yan-hong DU Ming-yuan GU Song 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第8期1396-1401,共6页
To understand the water and energy exchange on the Qinghai-Tibetan Plateau, we explored the characteristics of evapotranspiration (ET) and energy fluxes from 2002 to 2005 over a Kobresia meadow ecosystem using the e... To understand the water and energy exchange on the Qinghai-Tibetan Plateau, we explored the characteristics of evapotranspiration (ET) and energy fluxes from 2002 to 2005 over a Kobresia meadow ecosystem using the eddy covariance method. The ratio of annual ET to precipitation (P) of meadow ecosystem was about 60%, but varied greatly with the change of season from summer to winter. The annual ET/P in meadow was lower than that in shrub, steppe and wetland ecosystems of this plateau. The incident solar radiation (Rs) received by the meadow was obviously higher than that of lowland in the same latitude; however the ratio of net radiation (Rn) to Rs with average annual value of 0.44 was significantly lower than that in the same latitude. The average annual ET was about 390 mm for 2002-2005, of which more than 80% occurred in growing season from May to September. The energy consumed on the ET was about 44% of net radiation in growing season, which was lower than that of shrub, steppe and wetland on this plateau. This study demonstrates that the Kobresia meadow may prevent the excessive water loss through evapotranspiration from the ecosystem into the atmosphere in comparison to the shrub, steppe and wetland ecosystems of the Qinghai-Tibetan Plateau. 展开更多
关键词 eddy covariance EVAPOTRANSPIRATION net radiation PRECIPITATION Qinghai-Tibetan Plateau
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Health and Economic Impacts of Air Pollution in China: A Comparison of the General Equilibrium Approach and Human Capital Approach 被引量:6
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作者 YUE WAN HONG-WEI YANG TOSHIHIKO MASUI 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2005年第6期427-441,共15页
In China, combustion of fossil fuels and biomass has produced serious air pollution that does harm to human health. Based on dose-response relationships derived from epidemiological studies, the authors calculated the... In China, combustion of fossil fuels and biomass has produced serious air pollution that does harm to human health. Based on dose-response relationships derived from epidemiological studies, the authors calculated the number of deaths and people with health problems which were thought to be attributable to China's air pollution in the year of 2000. In order to estimate the corresponding economic impacts from the national point of view, the general equilibrium approach was selected as an analysis tool for this study. A computable general equilibrium (CGE) model was constructed involving 39 sectors and 32 commodities. The human capital approach (HCA) was also used for comparison. The economic burden of disease for people estimated by HCA was equivalent to 1.26‰ (ranging from 0.44‰ to 1.84‰) of China's gross domestic product (GDP). China's GDP loss estimated by the general equilibrium approach reached 0.38‰ (ranging from 0.16‰ to 0.51‰). The difference between the two approaches and the implications of the results were discussed. 展开更多
关键词 Air pollution HEALTH Economic impact CGE model Human capital approach
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An overview of the “Three-North” Shelterbelt project in China 被引量:12
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作者 LI Miao-miao LIU An-tian +3 位作者 ZOU Chun-jing XU Wen-duo Hideyuki SHIMIZU WANG Kai-yun 《Forestry Studies in China》 CAS 2012年第1期70-79,共10页
The "Three-North" Shelterbelt is the largest and most distinctive artificial ecological engineering project in China. It has been conducted since November 25, 1978 in the "Three-North" (i.e., Northeast China, Nor... The "Three-North" Shelterbelt is the largest and most distinctive artificial ecological engineering project in China. It has been conducted since November 25, 1978 in the "Three-North" (i.e., Northeast China, North China and Northwest China) regions. In this study, the background and the essential benefits of the "Three-North" Shelterbelt project are summarized. The basic status and future development of the "Three-North" Shelterbelt project are also studied. As well, we tried to discuss the problems existing in the current shelterbelt system and the strategies to conduct this ecological project rationally. 展开更多
关键词 "Three-North" Shelterbelt project essential benefits species adaptability
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华北平原地下水动态变化(英文) 被引量:3
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作者 王仕琴 宋献方 +3 位作者 王勤学 肖国强 刘昌明 柳鉴容 《Journal of Geographical Sciences》 SCIE CSCD 2009年第2期175-188,共14页
The groundwater level of 39 observation wells including 35 unconfined wells and 4 confined wells from 2004 to 2006 in North China Plain(NCP) was monitored using automatic groundwater monitoring data loggers KADEC-MIZU... The groundwater level of 39 observation wells including 35 unconfined wells and 4 confined wells from 2004 to 2006 in North China Plain(NCP) was monitored using automatic groundwater monitoring data loggers KADEC-MIZU II of Japan.The automatic groundwater sensors were installed for the corporation project between China and Japan.Combined with the monitoring results from 2004 to 2006 with the major factors affecting the dynamic patterns of groundwater, such as topography and landform, depth of groundwater level, exploitation or discharge extent, rivers and lakes, the dynamic regions of NCP groundwater were gotten.According to the dynamic features of groundwater in NCP, six dynamic patterns of groundwater level were identified, including discharge pattern in the piedmont plain, lateral recharge-runoff-discharge pattern in the piedmont plain, recharge-discharge pattern in the central channel zone, precipitation infiltration-evaporation pattern in the shallow groundwater region of the central plain, lateral recharge-evaporation pattern in the recharge-affected area along the Yellow River and infiltration-discharge-evaporation pattern in the littoral plain.Based on this, the groundwater fluctuation features of various dynamic patterns were interpreted and the influencing factors of different dynamic patterns were compared. 展开更多
关键词 地下水动态 浅层地下水 华北平原 水位观测井 放电模式 影响因素 山前平原 横向补给
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Review of Effective Vegetation Mapping Using the UAV (Unmanned Aerial Vehicle) Method 被引量:9
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作者 Korehisa Kaneko Seiich Nohara 《Journal of Geographic Information System》 2014年第6期733-742,共10页
We tried more precise mapping of vegetation using UAV?(unmanned aerial vehicle), as a new method of creating vegetation maps, and we?objected to be clearly the efficient mapping of vegetation using the UAV method by c... We tried more precise mapping of vegetation using UAV?(unmanned aerial vehicle), as a new method of creating vegetation maps, and we?objected to be clearly the efficient mapping of vegetation using the UAV method by comparing vegetation maps created by analysing aerial photographs taken by a UAV and an aircraft (manned flight). The aerial photography using UAV was conducted in the Niida River estuary (the secondary river flowing into Minamisoma City in Fukushima Prefecture, Japan). The photography period was in August 2013. We analysed the aerial photographs using ArcGis 9 (Esri Japan Corporation, Tokyo, Japan). The aerial photographs of the main plant communities (Phragmites australis,?Typha domingensis, and?Miscanthus sacchariflorus) taken by the UAV could clearly discriminate each plant community at the 1/50 scale. Moreover, it could clearly discriminate the shape of a plant at the 1/10 scale. We compared the vegetation maps by analysing the aerial photos taken by a UAV (2013 shooting) and an aircraft (2011 shooting). As a result, the vegetation map created by the UAV method could clearly discriminate community distributions. We conclude that vegetation surveys using UAV are possible and are capable of a highly precise community division in places where field reconnaissance is difficult. The UAV method is effective and will contribute to the improvement of research methods in the future;this method may reduce research costs associated with a reduction in field survey days and man-power. 展开更多
关键词 UAV (Unmanned AERIAL Vehicle) VEGETATION Map High Spatial RESOLUTION PLANT COMMUNITY PLANT Species
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SEASONAL CHANGES OF DISSOLVED AND PARTICULATE ORGANIC CARBON IN DONGHU LAKE,CHINA 被引量:3
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作者 刘学君 徐小清 +1 位作者 谢平 Noriko Takamura 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2000年第4期372-377,共6页
Concentrations of dissolved and particulate organic carbon (DOC and POC) were documented in 1996-1997 at 4 different trophic state stations in Donghu Lake, a typical shallow eutrophic lake along the Changjiang River’... Concentrations of dissolved and particulate organic carbon (DOC and POC) were documented in 1996-1997 at 4 different trophic state stations in Donghu Lake, a typical shallow eutrophic lake along the Changjiang River’s middle reaches. The mean concentrations of DOC were 15.11±3.26, 15.19±4.24, 14.27±3.43, and 13.31±3.30 mg/L in Station I, II, III, and IV, respectively. The DOC concentrations of the studied area were very similar to that in other lakes along the Changjiang River’s middle reaches. The POC mean of the whole lake was 5.01 mg/L due to the large amount of organic detritus of both allochthonous and autochthonous origin. Significant linear relationship was found between POC and chlorophyll a at all 4 stations, which presumably reflect that phytoplankton, its exudates and its metabolic products were the main contributors to the POC pool in the water column. The slope of such linear relationship at Station IV was significantly steeper than that at Station I, II and III. In addition, the DOC/POC ratios (mean value: 4.40) indicated that the organic detritus was the most important component of the particulate organic matter; in other words, next to organic detritus, phytoplankton dominated the particulate organic matter in Donghu Lake. 展开更多
关键词 dissolved organic carbon particulate organic carbon carbon constituents carbon cycling Donghu Lake
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Responses of gross primary productivity to different sizes of precipitation events in a temperate grassland ecosystem in Inner Mongolia, China 被引量:4
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作者 GUO Qun LI Shenggong +6 位作者 HU Zhongmin ZHAO Wei YU Guirui SUN Xiaomin LI Linghao LIANG Naishen BAI Wenming 《Journal of Arid Land》 SCIE CSCD 2016年第1期36-46,共11页
Changes in the sizes of precipitation events in the context of global climate change may have profound impacts on ecosystem productivity in arid and semiarid grasslands. However, we still have little knowledge about t... Changes in the sizes of precipitation events in the context of global climate change may have profound impacts on ecosystem productivity in arid and semiarid grasslands. However, we still have little knowledge about to what extent grassland productivity will respond to an individual precipitation event. In this study, we quantified the duration, the maximum, and the time-integrated amount of the response of daily gross primary productivity (GPP) to an individual precipitation event and their variations with different sizes of precipitation events in a typical temperate steppe in Inner Mongolia, China. Results showed that the duration of GPP-response (τ<sub>R</sub>) and the maximum absolute GPP-response (GPP<sub>max</sub>) increased linearly with the sizes of precipitation events (P<sub>es</sub>), driving a corresponding increase in time-integrated amount of the GPP-response (GPP<sub>total</sub>) because variations of GPPtotal were largely explained by τ<sub>R</sub> and GPP<sub>max</sub>. The relative contributions of these two parameters to GPP<sub>total</sub> were strongly P<sub>es</sub>-dependent. The GPP<sub>max</sub> contributed more to the variations of GPP<sub>total</sub> when P<sub>es</sub> was relatively small (<20 mm), whereas τ<sub>R</sub> was the main driver to the variations of GPP<sub>total</sub> when P<sub>es</sub> was relatively large. In addition, a threshold size of at least 5 mm of precipitation was required to induce a GPP-response for the temperate steppe in this study. Our work has important implications for the modeling community to obtain an advanced understanding of productivity-response of grassland ecosystems to altered precipitation regimes. 展开更多
关键词 precipitation event GRASSLAND gross primary productivity global climate change precipitation regime
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