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71.
赵魁义 《中国地理科学(英文版)》1998,8(1):44-52
FLOROGEOGRAPHYOFMIREPLANTSINSOUTHERNPARTOFQINGHAIXIZANGPLATEAUANDITSADJACENTAREASZhaoKuiyi(赵魁义)ChangchunInstituteofGeography... 相似文献
72.
Investigation of dissolved organic carbon (DOC) and particulate organic carbon (POC) at 12 stations in Yantal Sishili Bay in May, August, and November of 1997 and March and May of 1998 showed that DOC concentrations varied from 1.14 mg/L to 5.35 mg/L; that the average values at all staticrLs ineach entise varied from 1.52 mg/L to 2.12 mg/L; that POC concentrafions varied from 0.049 mg/L to 1.411mg/L; and averaged 0.159 mg/L to 0.631 mg/L in each cruise. Horizontal distribution of DOC was influ-enced by factors such as continental input, organism activity, temperature, aquieulture environment, etc. The higher POC concentration occurred along the coast. The vertical distribution of DOC and POC changed obviously in spring and summer, but not obviously in autumn and winter. DOC concentration was highest in summer and POC in spring; both were lowest in winter. The seasonal change of DOC was con-sistent with primary productivity seasonal variation, and that of POC was consistent with ehlorophyll-a sea-sanal variation. The seasonal change trend of the C/N ratio of dissolved organic matter was obvious, but the C/N ratio of particulate organic matter had no such trend. 相似文献
73.
INTRODUCTIONBiogenicsulfideproducedbybacterialsulfatereductionisoneofthemostimportantindicatorsinanoxicmarineenvironments,particularlyinconfiningbays,pollutedestuariesandaquaculturear eas.Theincreaseofitsconcentrationusuallyindicatesworsenedconditions.… 相似文献
74.
?о???????EGM??DTM???????????????????????????????????????EGM2008??SRTM3???????????????????????????????????????????????????Tzz???????????????????μ??????????????????????????????????????????????????????????????????????????????????????λ???????????????仯??????λ???????ж?????????????????????????????????????????? 相似文献
75.
??????????????????(VTEC)??????????????????????????????????4?????????????????????Э????????????????С???????÷????????????????????????г????????????????????????????????????????????????????????(CODE)????????????????????????0.812???????????ο???в???4 TECu????????????????????????????????????????????γ20°?????????????????????????????????????1??7 TECu?????????????????2.4 TECu?????CODE????????20.14%????????????????3.5 TECu?????CODE???????????????????3.0 TECu?????CODE????????8.25%?? 相似文献
76.
77.
0引言莱芜市莱城区位于鲁中地区,辖15个乡镇(办事处),865个行政村(居委会),总面积1 853 km2,人口94.2万。境内已发现54种矿产,其中已探明储量的矿产有22种,以煤、铁资源最为丰富。铁矿以富矿为主,资源储量约4.5亿t;煤矿资源储量约8亿t。区内矿山企业160处,总生产能力1.33×107t/a。由于区内地形复杂,矿山企业分散,给矿产资源的管理带来很大难度。 相似文献
78.
Little is known about the genome of Pacific white shrimp (Litopenaeus vannamei). To address this, we conducted BAC (bacterial artificial chromosome) end sequencing of L. vannamei. We selected and sequenced 7 812 BAC clones from the BAC library LvHE from the two ends of the inserts by Sanger sequencing. After trimming and quality filtering, 11 279 BAC end sequences (BESs) including 4 609 paired- ends BESs were obtained. The total length of the BESs was 4 340 753 bp, representing 0.18% of the L. vannamei haploid genome. The lengths of the BESs ranged from 100 bp to 660 bp with an average length of 385 bp. Analysis of the BESs indicated that the L. vannamei genome is AT-rich and that the primary repeats patterns were simple sequence repeats (SSRs) and low complexity sequences. Dinucleotide and hexanucleotide repeats were the most common SSR types in the BESs. The most abundant transposable element was gypsy, which may contribute to the generation of the large genome size of L. vannamei. We successfully annotated 4 519 BESs by BLAST searching, including genes involved in immunity and sex determination. Our results provide an important resource for functional gene studies, map construction and integration, and complete genome assembly for this species. 相似文献
79.
?????????????GNSS???????????????????????????λ???????????????????3????????????3??GNSS???????????????GNSS??????????????μ????????????????????????????????????£??????????????????3????????????????????????????????????????????????????????????????????????????????????????????λ??????????????????????????????з???3.0?????????????????о??д???????????? 相似文献
80.
Lancelets (subphylum Cephalochordata) are a transitional species between invertebrates and vertebrates. They are currently listed in the Second Order of Protected Animals in China. Lancelets were first documented in the waters around the city of Weihai (Shandong, China) in 2002. However, little is known about the phylogeny of this population. We analyzed the sequences of cytochrome b (Cyt b) and cytochrome oxidase c subunit I (CO I) genes from samples collected from coastal waters in the cities of Weihai and Qingdao (~150 km to the south). We analyzed 176 sequences, of which 150 were novel sequences and 26 were obtained from GenBank. Our results suggest that (1) lancelets in the two cities belong to the species Branchiostoma japonicus and have a high level of genetic diversity; (2) there is a high level of gene flow and low level of genetic differentiation between lancelets from the two cities; (3) demographic expansion occurred an estimated 1.1 million years (Ma) ago (mid Pleistocene) for lancelets in Weihai-Qingdao; and (4) the divergence between B. belcheri and B. japonicus was estimated at between 37.75 Ma (early Oligocene)-46.5 Ma (late Eocene). 相似文献