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排序方式: 共有193条查询结果,搜索用时 15 毫秒
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Sapundzhiev E Pupaki D Zahariev P Georgiev G Ivanov I 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2007,54(9):499-500
The result of the histological diagnosis from postmortal investigation of the Indian elephant (Elephas maximus) uterus structure is presented in the current study. The rare anatomical finding showed altered nodular part from the uterus wall. Through conventional and histochemical staining neoplasmatic formations were determined and diagnosis Fibroleiomyoma was established, which should not be accepted as the prime cause for the animal's death. 相似文献
3.
The phenomenon of mineralization (biological mineralization) of organic matter in chernozems has been studied. A decrease
in the content of Corg with time can be considered an index of the organic matter mineralization. It is suggested that the humus horizons of modern
chernozems contain the pools of organic matter of different ages: easily decomposable organic matter, labile biologically
active humus, stable biologically active humus, and relatively inert humus. The composition and mean residence times of these
pools and their contribution to the total organic matter content have been estimated. The particular types of the biological
mineralization have been determined on the basis of the comparison between the velocities of mineralization (M) and humification
(H) processes: total unidirectional mineralization (M ≫ H), equilibrium mineralization (M ∼ H), nonequilibrium mineralization
(M> <H), and zero mineralization. The separation of subtypes is based on data on the relative rates (%) of the organic matter
mineralization. On the basis of available experimental data on chernozems buried under kurgans and in loess sediments (with
the age of up to 800 ka), the quantitative relationship of the humus content in the buried soils on their age has been found;
it has an exponential shape. During the first 100 ka after the soil burial, the soil humus content gradually (with a slowing
intensity) decreases from 100–75 to 6.5% of its content in the virgin chernozems. Then, 100–1000 ka after the soil burial,
the soil humus content remains approximately constant (6.5% of the initial level, or 0.3% of the soil mass). The rates of
mineralization have been estimated. It is shown that the elemental composition (C, H, N, O) of humic acids remains relatively
stable for a long time due to the regeneration of the chemical structure of humus (matric restoration of humus). It is suggested
that several different forms of humus related to pedogenesis should be distinguished in the biosphere. The renewable humus
in the equilibrium state with the environment is typical of the open biospheric (soil) systems. The fossil humus, whose content
decreases with time, and whose composition remains stable, is typical of the semiclosed and closed systems. With time, it
transforms into residual humus, whose content and composition remain stable. The fossilized organic matter in the fossil soils
and sediments of the past geological epochs (Mesozoic and Paleozoic) considerably differs from the renewable, fossil, and
residual humus. 相似文献
4.
5.
G.?GeorgievEmail author T.?Ljubomirov M.?Raikova K.?Ivanov V.?Sakalian 《Journal of pest science》2004,77(4):235-243
The complex of insect inhabitants of old larval galleries of Saperda populnea (L.) (Coleoptera: Cerambycidae) was studied during the period 2000–2003 in 18 localities in Bulgaria. As a result, 32 insect species were reared from old S. populnea galls: Metopoplax origani (Kolenati) (Heteroptera: Lygaeidae), Malachius sp. (Coleoptera: Malachiidae), Agrilus pratensis pratensis (Ratzeburg) (Coleoptera: Buprestidae), Xylocleptes bispinus (Duftschmidt) (Coleoptera: Scolytidae), Crossocerus cetratus (Shuckard), Crossocerus megacephalus (Rossi), Crossocerus nigritus (Lepeletier & Brullé), Crossocerus acanthophorus (Kohl), Passaloecus brevilabris Wolf, Passaloecus gracilis (Curtis), Psenulus schencki (Tournier), Solierella compedita compedita (Piccioli), Trypoxylon figulus figulus (Linnaeus), Trypoxylon fronticorne fronticorne Gussakovskij (Hymenoptera: Crabronidae), Cleptes schmidti Linsenmaiser, Trichrysis cyanea (Linnaeus) (Hymenoptera: Chrysididae), Clistopyga incitator (Fabricius), Ctenochira sanguinatoria (Ratzeburg), Liotryphon crassisetus (Thomson), Nemeritis fallax (Gravenhorst), Mesochorus georgievi Schwenke, Campoletis sp. (Hymenoptera: Ichneumonidae), Charmon extensor (Linnaeus) (Hymenoptera: Braconidae), Eupelmus urozonus Dalman (Hymenoptera: Eupelmidae), Perilampus aeneus (Rossius) (Hymenoptera: Perilampidae), Trichiocampus grandis (Lepeletier) (Hymenoptera: Tenthredinidae), Janus luteipes (Lepeletier) (Hymenoptera: Cephidae), Cydia corollana (Hübner) (Lepidoptera: Tortricidae), Fiebrigella brevibucca (Duda) (Diptera: Chloropidae), Eustolomyia hilaris (Fallén) (Diptera: Anthomyiidae), Senotaina sp. (Diptera: Sarcophagidae) and Heringia vitripennis (Meigen) (Diptera: Syrphidae). Amongst them, 27 species were established as new inhabitants of old S. populnea galls. Five species (C. schmidti, N. fallax, M. georgievi, P. aeneus and J. luteipes) were recorded for the first time in Bulgaria. The dwellers of old S. populnea galls belong to the following ecological groups: insects using galls as a place to develop (3 species); insects nidificating in empty galls (10 species); insects using old galls as a pupating place (1 species); insects using empty galls as overwintering shelters (3 species); predators and parasites of primary dwellers of empty galls (13 species); or insects with uncertain ecological status (2 species). 相似文献
6.
L. V. Lysak M. S. Kadulin I. A. Konova E. V. Lapygina A. V. Ivanov D. G. Zvyagintsev 《Eurasian Soil Science》2013,46(6):668-675
It is shown for the first time that a significant part of the bacteria (up to 40%) in the iron-manganic concretions of soddy-podzolic and soddy meadow soils are represented by nanoforms; their number reaches 600–700 million cells/g. Judging from the specific luminescent coloration, the fraction of viable cells among the bacterial nanoforms is very high in the concretions and amounts up to 88–99%. For the first time, the following phyla were identified among the bacterial nanoforms in the concretions with the use of the FISH method: Alphaproteobacteria, Betaproteobacteria, Gammaproteobateria, Deltaproteobacteria, Acidobacteria, and Planctomycetes. The Gammaproteobacteria phylum predominated in the concretions from the soddy-podzolic soil, and the Deltaproteobacteria phylum predominated in the concretions from the soddy meadow soil. In the alluvial meadow soil, the Alphaproteobacteria, Betaproteobacteria, and Acidobacteria phyla were found. The significant number and portion of bacterial nanoforms in the concretions, their high vitality, and their taxonomic diversity allow us to conclude that the bacterial nanoforms play an important role in the processes taking place in the concretions. 相似文献
7.
Ivanov I. V. Prikhodko V. E. Zamotaev I. V. Manakhov D. V. Novenko E. Yu. Kalinin P. I. Markova L. M. Plaksina A. L. 《Eurasian Soil Science》2019,52(6):593-609
Eurasian Soil Science - The relationship between soil formation and sedimentation on the floodplain of the Utyaganka River (the Ural River basin) in the Arkaim Reserve (Chelyabinsk oblast, Southern... 相似文献
8.
Data on radiocarbon ages of different fractions of humus (humic acids, fulvic acids, and humin) in the profiles of chernozems
are analyzed. A chronoecological grouping of humus in modern and buried (fossil) soils is suggested. An increase in the radiocarbon
age of humic substances down the soil profile has a stepwise character. It is shown that the 14C content in chernozems decreases down the soil profile more somewhat slower than the 12C content. The dependence of a decrease in the humus content of buried soils on the age of burying is traced for a time span
of 800 ka. 相似文献
9.
10.
An overview of modern ideas on the ecological and geochemical state of soils and vegetation in the sites of landfills and municipal solid waste storage is presented. The technogenic impact on the environment and soil is determined by the (1) withdrawal of land for landfills, (2) production of filtration water with toxic components upon decomposition of solid wastes, and (3) biogas generation. The heavy metal pollution of surface soil horizons is characteristic for the sites of solid waste storage and their impact zones irrespectively of climatic conditions, ways of waste management, and stages of the life cycle. At the same time, heavy metals accumulate in ruderal herbaceous plants. Changes in the geochemical and microbiological characteristics of soils and disturbances in the plant cover are not restricted to the area of the designated sanitary protection zone. Buried landfills, where the decomposition of organic matter under anaerobic conditions results in the production of carbon dioxide and methane with their concentration in the soil and ground air also become dangerous for the environment. In the sites of landfills and municipal solid waste storage, weakly developed surface and chemically transformed soils, technosols and technogenic surface formations are being formed. 相似文献