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河南浙川滔河盆地“红层”划分及时代 被引量:6
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作者 周世全 李占扬 冯祖杰 《华北地质矿产杂志》 1999年第1期45-51,共7页
滔河盆地位于豫—鄂两省毗邻地区。盆内沉积了一套1600 m 左右的粗碎屑岩系, 根据恐龙蛋、恐龙、轮藻化石和岩性特征, 划分为高沟组马家村组、寺沟组, 时代归属于晚白垩世。其时代的厘定, 为我省众多的中、新生代 “红层”的... 滔河盆地位于豫—鄂两省毗邻地区。盆内沉积了一套1600 m 左右的粗碎屑岩系, 根据恐龙蛋、恐龙、轮藻化石和岩性特征, 划分为高沟组马家村组、寺沟组, 时代归属于晚白垩世。其时代的厘定, 为我省众多的中、新生代 “红层”的研究与矿产预测, 无疑提供了十分重要的材料。 展开更多
关键词 恐龙蛋 轮藻 生物群性质 晚白垩世 红层 盆地
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Spatial heterogeneity in a deep artificial lake plankton community revealed by PCR-DGGE fingerprinting 被引量:8
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作者 李强 赵越 +4 位作者 张旭 魏雨泉 邱琳琳 魏自民 李富恒 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第3期624-635,共12页
To explore the spatial heterogeneity of plankton communities in a deep artificial lake (Songhua Lake, China), samples were collected at seven sites. Samples were investigated by denaturing gradient gel electrophores... To explore the spatial heterogeneity of plankton communities in a deep artificial lake (Songhua Lake, China), samples were collected at seven sites. Samples were investigated by denaturing gradient gel electrophoresis (DGGE) analysis of the PCR-amplified 16S and 18S rRNA genes and specific bands were sequenced. Cluster analysis of the DGGE profiles revealed that all of the samples grouped into two distinct clusters, in accordance with sampling site; while in each cluster, the divergence of sub-clusters correlated with sampling depth. Sequence analysis of selected dominant DGGE bands revealed that most sequenced phylotypes (84%) exhibited 〉97% similarity to the closest sequences in GenBank, and were affiliated with ten common freshwater plankton phyla (Proteobacteria, Actinobacteria, Bacteroidetes, Cyanobacteria, Bacillariophyta, Pyrrophyta, Cryptophyta, Ciliophora, Stramenopiles, and Rotifera). Several of these groups are also found worldwide, indicating the cosmopolitan distribution of the phylotypes. The relationships between DGGE patterns and environmental factors were analyzed by redundancy analysis (RDA). The results suggested that, total nitrogen, nitrate, nitrite, temperature were strongly correlated with the variation ammonia, and CODMn concentrations, and water in plankton composition. 展开更多
关键词 Songhua Lake plankton community composition denaturing gradient gel electrophorcsis (DGGE) artificial lake redundancy analysis
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Relationship Between Microbial Community and Soil Properties During Natural Succession of Abandoned Agricultural Land 被引量:3
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作者 JIA Guo-Mei ZHANG Pei-Dong +3 位作者 WANG Gang CAO Jing HAN Jing-Cheng HUANG Ying-Ping 《Pedosphere》 SCIE CAS CSCD 2010年第3期352-360,共9页
The changes of microbial biomass carbon (MBC) and nitrogen (MBN) and microbial community in the topsoil of the abandoned agricultural land on the semi-arid Loess Plateau in China during the natural succession were eva... The changes of microbial biomass carbon (MBC) and nitrogen (MBN) and microbial community in the topsoil of the abandoned agricultural land on the semi-arid Loess Plateau in China during the natural succession were evaluated to understand the relationship between microbial community and soil properties. MBC and MBN were measured using fumigation extraction, and microbial community was analyzed by the method of fatty acid methyl ester (FAME). The contents of organic C, total N, MBC, MBN, total FAME, fungal FAME, bacterial FAME and Gram-negative bacterial FAME at the natural succession sites were higher than those of the agricultural land, but lower than those of the natural vegetation sites. The MBC, MBN and total FAME were closely correlated with organic C and total N. Furthermore, organic C and total N were found to be positively correlated with fungal FAME, bacterial FAME, fungal/bacterial and Gram-negative bacterial FAME. Natural succession would be useful for improving soil microbial properties and might be an important alternative for sustaining soil quality on the semi-arid Loess Plateau in China. 展开更多
关键词 fatty acid methyl ester microbial biomass soil carbon soil nitrogen
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Seasonal Effect of Geomorphological Chronosequence Features on Soil Biota Dynamics 被引量:1
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作者 S.PEN-MOURATOV N.GENZER +2 位作者 N.SHUKUROV J.PLAKHT Y.STEINBERGER 《Pedosphere》 SCIE CAS CSCD 2010年第6期761-770,共10页
Numerous studies have been devoted to the physical-chemical weathering processes leading to the creation of unique soil formations having their own history that induce soil-biotic diversity.However,the extent to which... Numerous studies have been devoted to the physical-chemical weathering processes leading to the creation of unique soil formations having their own history that induce soil-biotic diversity.However,the extent to which unique geomorphic formations influence soil biotic seasonal variation is not clear.Our aim was to define seasonal variations of soil biota in soils of different-aged terraces of the Makhtesh Ramon anticline erosional cirque in southern Israel.The strong effect of Makhtesh Ramon (Ramon crater) erosional fluvial terrace age initiated by climatic changes during the Late Pleistocene- Early Holocene period on seasonal variations in both soil properties and the abundance and composition of soil biota were demonstrated.However,age dependence was not constant and values for observed soil properties and microbial activity were negligible between younger and older terraces for certain seasons,while free-living nematodes along with bacterial-feeding group were strongly dependent on the geomorphic features of the ages throughout the study period. 展开更多
关键词 geomorphic formation Makhtesh Ramon microbial biomass nematode community trophic group
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