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81.
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The effect of treeshelter height on the early growth of sessile oak (Quercus petraea (Matt.) Liebl.)
Sessile oak 1+1 transplants were grown for 4 years in a weed-freeenvironment at 1 x 1 m spacing on a fertile sheltered site.Four experiment treatments were imposed: control with no treeshelterand treeshelters of heights 0.6 m, 1.2 m and 1.8 m. Treatmentshad no significant effect on tree survival. Taller sheltersproduced taller, lower diameter trees of increasingly low dryroot weight. The root:shoot ratio was 0.675 in control treesbut declined to 0.291 in 1.8-m shelters. Trees from 0.6-rn and1.2-m shelters (mean heights 152 m and 206 m respectively) supportedthemselves unaided after removal of the stake and treeshelter.The trees from 1.8-m shelters of mean height 234 cm at age fourcollapsed completely when support was removed. 相似文献
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85.
In addition to luteolin and its 7-methyl ether, the CH2Cl2-MeOH (1:1) extract of Cyperus conglomeratus afforded two new prenylflavans identified as 7,3'-dihydroxy-5,5'-dimethoxy-8-prenylflavan and 5,7,3'-trihydroxy-5'-methoxy-8-prenylflavan. The structures were established by CIMS, 1H-NMR, 13C-NMR, H-H COSY, HMQC, HMBC and DEPT analysis. 相似文献
86.
A. I. Kurapova G. M. Zenova V. K. Orleanskii A. S. Manucharov Zh. Norovsuren 《Moscow University Soil Science Bulletin》2008,63(3):142-147
Mesophilic and thermotolerant actinomycetes were identified in strongly heated desert-steppe soils of Mongolia, mountainous meadow soils of the Central Caucasus, and cyanobacterial films on volcanic ash near hot springs of Kamchatka. Thermotolerant actinomycetes in these soil objects were more abundant and had a greater taxonomic diversity in comparison with mesophilic actinomycetes. Thermotolerant Streptomyces were present in all the objects, except for sample 117 from the desert-steppe soil and the cyanobacterial film on volcanic ash. Thermotolerant actinomycetes from the Micromonospora and Actinomadura genera predominated in the desert-steppe soil; representatives of the Micromonospora genus predominated in the cyanobacterial film on volcanic ash, and representatives of the Microtetraspora genus predominated in the samples of geyserite near hot springs of Kamchatka. 相似文献
87.
Eurasian Soil Science - The inhibition of seeds of grain crops germination in soils of the East European Plain in comparison with sand has been found. It resulted from the pot experiments that the... 相似文献
88.
Kirillova N. P. Sileva T. M. Makarov M. I. Artemyeva Z. S. Burova E. K. 《Eurasian Soil Science》2019,52(2):133-140
Eurasian Soil Science - Experimental data on 1029 soil profiles examined in the area of the Chashnikovo Experimental and Training Soil-Ecological Center of Moscow State University in Moscow region... 相似文献
89.
Eurasian Soil Science - The ameliorative status of irrigated soils was estimated on the basis of reclamation cadaster data for 2001 and 2016 on 17 state irrigation systems in three nature regions... 相似文献
90.
Eurasian Soil Science - The relevance of the study of antibiotic resistance of microorganisms in specially protected natural areas is due to the need to control the spread of resistance among... 相似文献