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Estimation of above-ground biomass and carbon stock of an invasive woody shrub in the subtropical deciduous forests of Doon Valley,western Himalaya,India 被引量:8
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作者 Gautam Mandal S.P.Joshi 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第2期291-305,共15页
This study describes the different parameters used to derive the allometric equation for calculating the biomass of an invasive woody shrub Lantana camara L.from the subtropical conditions of western Himalaya.It ident... This study describes the different parameters used to derive the allometric equation for calculating the biomass of an invasive woody shrub Lantana camara L.from the subtropical conditions of western Himalaya.It identifies the most accurate and convenient method for biomass calculation by comparing destructive with nondestructive methodology.Different parameters were measured on a wide range of Lantana from different community levels for the non-destructive calculation of total aboveground biomass.Different explanatory variables were identified and measured such as basal diameter either as a single independent variable or in combination with plant height.The other suitable combinations of available independent variables include crown length,crown width,crown area,crown volume and coverage of the plant.Amongst the wide range of allometric equations used with different variables,the equation with D2 H as a variable was found to be the most suitable estimator of biomass calculation for Lantana.Sahastradhara,being the most disturbed area due to its high tourist activity round the year,showed maximum coverage(58.57 % ha-1),highest biomass(13,559.60 kg ha-1) and carbon density(6,373.01 kg ha-1)of Lantana.The degree of Lantana’s invasiveness in subtropical conditions was also calculated on the basis of importance value index(IVI).The maximum IVI(22.77)and mean coverage(26.8 % ha-1) was obtained from the areas near Jolly Grant airport,indicating that physically disturbed areas are more suitable for the growth of Lantana,which may significantly increase shrub biomass.The importance of incorporating allometric equations in calculation of shrub biomass,and its role in atmospheric carbon assimilation has thus been highlighted through the findings of this study. 展开更多
关键词 Above ground carbon pools Allometric regression equations Carbon density Importance value index(IVI) Shrub biomass
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Comparison of Ground Water Bacterial Cell Sizes from the Agricultural, Domestic and Industrial Areas of Mysore District, Karnataka State, India
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作者 Wadie Ahmed Mokbel Sadanand M Yamakanamardi 《应用与环境生物学报》 CAS CSCD 北大核心 2008年第4期503-509,共7页
A two-year study on temporal variations in the ground water heterotrophic bacterial cell sizes of free living bacteria (FLB) and particle bound bacteria (PBB) from the agricultural, domestic and industrial areas was c... A two-year study on temporal variations in the ground water heterotrophic bacterial cell sizes of free living bacteria (FLB) and particle bound bacteria (PBB) from the agricultural, domestic and industrial areas was carried out from February 2005 to January 2007. The overall mean cell length of FLB and PBB was similar in all the ground water studied. However, the season wise grouped data revealed significant seasonal changes in cell length of FLB and PBB, as smaller bacteria were noticed during rainy season in the ground water in agricultural area in both the years, and only in the second year of study in domestic and industrial areas. Generally, it was noticed that there were summer maximum and rainy minimum values of the cell length of PBB in the ground water in agricultural, domestic and industrial areas in the second year of study. The Pearson's correlations showed the presence of 8 (in agricultural area), 5 (in domestic) and 3 (in industrial) significant correlations with environmental (Physico-chemical) parameters, respectively. The regression analysis revealed that as much as 12% of variation in the mean length of FLB was due to NO3 (+) in agricultural area and 9% due to total solids (+) in domestic area. However, the 8 % variation in bacterial cell size of FLB was due to Mg (+) in industrial area. Whereas, 13 % variation in mean length of PBB was due to SO4 (+) in agricultural area and 10% due to total anions of strong acid (TASA) (+) in domestic area. Furthermore, 10 % of variation was due to PO4 (+) in industrial area. Thus, the statistical analysis revealed that several environmental variables were potentially responsible for some of the temporal variations in aquatic heterotrophic bacterial cell size, suggesting probably the stressed environment in these ecosystems. 展开更多
关键词 地下水 微生物 细胞 环境保护
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源自车辆的微粒磁性与Ficus infectoria(一个关键种)对它的改善
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作者 Sudhir Kumar Pandey B.D.Tripathi +5 位作者 Santosh Kumar Prajapati Virendra Kumar Mishra Alka Rani Upadhyaya Prabhat Kumar Rai Atul Prakash Sharma 王胜 《AMBIO-人类环境杂志》 2005年第B12期639-640,共2页
引言 源自车辆燃烧的磁性矿物质主要是磁铁矿和金属铁颗粒,大小为0.1~0.7 μm[1].这种大小的颗粒对人类特别有害,因为它能被吸入肺里.而且,在悬浮尘粒中,磁铁与其它重金属(如锌、镉、铬)[2]和对人体健康有害的诱变有机化合物[3]结合在... 引言 源自车辆燃烧的磁性矿物质主要是磁铁矿和金属铁颗粒,大小为0.1~0.7 μm[1].这种大小的颗粒对人类特别有害,因为它能被吸入肺里.而且,在悬浮尘粒中,磁铁与其它重金属(如锌、镉、铬)[2]和对人体健康有害的诱变有机化合物[3]结合在一起. 展开更多
关键词 车辆排放 磁性 关键种 微粒 车辆制动系统 燃烧过程 有机化合物 不规则形状 铁颗粒 人体健康
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利用无忧树和五色梅树叶生物监控机动车辆释放的PM_(10)中的微量元素水平
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作者 Santosh K. Prajapati B. D. Tripathi +1 位作者 张宝雷(译) 张淑敏(校) 《AMBIO-人类环境杂志》 2007年第B12期663-664,共2页
通过研究大气粒子以及两种植物一无忧树(Saraca indica)和五色梅(Lantana camara)树叶中小于10μm(PM10)颗粒物中可吸入微量元素(钡、铜、铁、锰、铅、钛和钒)的组成和水平,来显示它们之间的关系。树叶从瓦拉纳西(Varanasi)... 通过研究大气粒子以及两种植物一无忧树(Saraca indica)和五色梅(Lantana camara)树叶中小于10μm(PM10)颗粒物中可吸入微量元素(钡、铜、铁、锰、铅、钛和钒)的组成和水平,来显示它们之间的关系。树叶从瓦拉纳西(Varanasi)周围的两个地点采集,一个是偏远的对照点(村庄),它的交通量可以被忽略不计,另一个位于城市的中心,交通量很大。 展开更多
关键词 微量元素 五色梅 PM10 机动车辆 生物监控 树叶 大气粒子
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Assessing the relative role of climate and human activities on vegetation cover changes in the up-down stream of Danjiangkou,China 被引量:3
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作者 Hai Liu Feng Liu +2 位作者 Hongmeng Yuan Liang Zheng Yuan Zhang 《Journal of Plant Ecology》 SCIE CSCD 2022年第1期180-195,共16页
Danjiangkou Reservoir is water source of Middle Route Project of the South-to-North Water Diversion(SNWD)Project,research on the dynamic changes in vegetation cover and its influencing factors is of great significance... Danjiangkou Reservoir is water source of Middle Route Project of the South-to-North Water Diversion(SNWD)Project,research on the dynamic changes in vegetation cover and its influencing factors is of great significance for understanding the ecological environment of the water diversion area and formulating protection measures.In this study,the normalized difference in vegetation index(NDVI)was used to analyze the dynamic changes and influencing factors of vegetation in the upstream and downstream of Danjiangkou Dam from 1982 to 2018.The results showed that the NDVI exhibited an upward trend of 0.017 year−1(P<0.05),and that the significantly increased area was located near the valley upstream of the dam,while the significantly decreased area was mainly distributed in the basin downstream of the dam and around the central city.The comprehensive contributions of climate and human activity factors to NDVI changes were 92.03%and 7.97%,respectively.The human activities in the upstream of the dam were mainly reflected in the ecological measures such as returning farmland to forest;the human activities at the downstream of the dam were mainly reflected in urban expansion,occupation of cultivated land and forest land by construction land. 展开更多
关键词 remote sensing monitoring NDVI climate change urban expansion returning farmland to forest
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Humidity and seasonality drives body size patterns in males of the bush cricket Isophya rizeensis Sevgili, 2003 (Orthoptera: Tettigoniidae: Phaneropterinae) 被引量:1
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作者 Selim S. Cagasan Cagasan Karacaoglu A. Cem Kuyucu ismail K. Saelam 《Insect Science》 SCIE CAS CSCD 2014年第2期213-226,共14页
Two primary patterns of body size variation have been recorded in ectotherms in relation to latitudinal/altitudinal shifts. In some, body size increases with increasing latitude/altitude whereas, in others, body size ... Two primary patterns of body size variation have been recorded in ectotherms in relation to latitudinal/altitudinal shifts. In some, body size increases with increasing latitude/altitude whereas, in others, body size decreases with increasing latitude/altitude. This clinal variation is generally assumed to be caused by local adaptation to environmental conditions however the selective variable(s) (temperature, humidity, diet quality, etc.) is still heavily debated. Here we investigate geographic variation in body size of dark and pale color morphs of males of the bush-cricket lsophya rizeensis collected from 15 locations along an elevation gradient ranging from 350 to 2 500 m. Using an information theoretical approach we evaluate the relative support of four different hypotheses (the temperature size rule, the moisture gradient hypothesis, the seasonal constraint hypothesis, and the primary productivity hypothesis) explaining body size variation along the altitudinal gradient. Body size variation in pale color morphs showed a curvilinear relationship with altitude while dark color morphs showed no variation in body size. Body size variation in pale color morphs was highly correlated with precipitation and temperature seasonality values thus giving strong support for the moisture gradient and seasonal constraint hypothesis. Our results reinforce the importance of gradients in humidity and seasonality over temperature in the creation of altitudinal body size clines and the role of selection for resistance to stress factors in the establishment of these clines. Whether a body size cline is observed or not might also depend on the phenotypic properties of the individuals, like coloration. 展开更多
关键词 altitude Bergmann's rule converse Bergmann's rule Flrtlna Valley information-theoretic temperature size rule
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