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Agricultural University (agricultural + university)

Distribution by Scientific Domains

Earth and Environmental Science	40%

Selected Abstracts

Effect of organic matter applications on 13C-NMR spectra of humic acids of soil

EUROPEAN JOURNAL OF SOIL SCIENCE, Issue 3 2008
S. Dou
Summary Much attention has been paid to improving soil fertility with organic matter (OM) application, which not only deals with organic wastes and protects the environment, but also maintains soil fertility and increases crop yields. Much research has also been on the effects of OM applications on the soil's physical, chemical and biological properties, but relatively less attention has been spent on humic substance (HS). In order to clarify the mechanism of improving soil fertility by applying OM, we analysed the changes of structural characteristics of humic acid (HA) from OM applications to soils by 13C-NMR, chemical analysis, thermal analysis, optical properties, IR and fluorescence spectroscopy. Samples of a brown soil (Paleudalf) and a paddy soil (an anthropogenic soil originating from Udifluvents) were collected from the plough layer of the long-term field experiment at Shenyang Agricultural University and Liaoning Provincial Alkali-Saline Soil Institute, respectively. Both field experiments included three treatments each: (i) brown soil, zero-treatment (CKbr) and two pig manure (PM) applications (O1 and O2) at annual rates of 0.9 t ha,1 and 1.8 t ha,1 of organic carbon, respectively; and (ii) paddy soil, zero-treatment (CKpad), pig manure (Op) and rice straw (Or) at annual rates of 2.62 t ha,1 and 1.43 t ha,1 of organic carbon, respectively. An incubation experiment was also carried out to test the field experiment on the brown soil, namely four treatments: zero-treatment (CKc), and three pig manure applications at rates of 30 g kg,1 (C1), 50 g kg,1 (C2) and 70 g kg,1 (C3), respectively. The total incubation was 180 days. The results indicated that number-average molecular weights (Mn), total acidity, aromaticity, excitation maximum wavelength (,Exmax), and the heat ratio of the high to moderate temperature exothermic regions (H3/H2) of the HA all decreased after OM application. The degree of activation (AD), the absorption intensity ratio of 2920 cm,1 to 1720 cm,1 in infrared spectra (IR2920/1720), alkyl C and O-alkyl C of the HA increased. The HA structure tended to become simpler and more aliphatic. [source]

A NEW SPECIES OF THE GENUS DIRRHOPE (HYMENOPTERA: BRACONIDAE) FROM CHINA*

INSECT SCIENCE, Issue 3 2000
WU Zhi-shan
Abstract The subfamily Dirrhopinae van Achterberg and the genus Dirrhope Foerster (Hymenoptera: Braconidae), both are recorded for the first time from China. Dirrhope shaxvi is also reported new to science in this paper. Type specimens of this new species are kept in the Beneficial Insects Lab, Fujian Agricultural University, Fuzhou, China. [source]

NOTES ON A NEW SPECIES AND A NEW RECORD OF THE GENUS CENTISTIDEA HALIDAY (HYMENOPTERA: BRACONIDAE) FROM CHINA

INSECT SCIENCE, Issue 2 2000
WU Zhi-shan
Abstract, A new species and a new record of the genus Centistideu Haliday (Hymenoptera: Braconidae:) are reported from China in this paper. Centistideu immitis Wu et Chen is new to science and Centistideu irruptor (Papp) is recorded for the first time from China. Key to the species of the genus paper is also provided. The type specimens and other material examined are deposited in the Beneficial Insects Lab, Fujian Agricultural University, Fuzhou. [source]

TWO NEW SPECIES OF SUBGENUS CALCEORHOPALUM TSUNEKI FROM CHINA (HYMENOPTERA: SPHECIDAE)

INSECT SCIENCE, Issue 1 2000
LI Qiang
Abstract, Two new species of the subgenus Calceorhopalum Tsuneki of the genus Rhopalum Stephens are described. The new species, Rhopalum (Calceorhopalum) odontodorsale sp. nov. from Sichuan and Guizhou Province, is similar to R. (C.) spinicollum Tsuneki, but can be distinguished from the latter in the shape of clypeus, vertex with denser and larger punctures, anterior lateral corner of collar with a small tooth, tarsomere I of fore legs rather broad in male, and the shape of male genitalia. Holotype (,) is deposited in the Insect Collections of Institute of Zoology, Chinese Academy of Sciences. Paratypes (9 ,, 14 2 2) are deposited in the Insect Collections of Institute Zoology, Chinese Academy of Sciences and the Insect Collections of Zhejiang Agricultural University separately. The other new species, Rhopalum (Calceorhopalum) rubigabdominale sp. nov. from Sichuan Province, is similar to R (C.) spinicollum Tsuneki also, but can be distinguished from the latter by the characters of the vertex concave, anterior lateral comer of collar rounded, posterior lateral corner of propleuron with a coarse and long tooth, prepectus with blunt comer medially, head and thorax with denser and larger punctures, abdomen yellowish or reddish brown, and the shape of male genitalia. Holotype (,) and paratypes (3,,) are kept in the Insect Collections of Institute Zoology, Chinese Academy of Sciences. [source]

Changes of nase Chondrostoma nasus L. occurrence in the Wislok River, southern Poland, after stocking with pond reared juveniles

JOURNAL OF FISH BIOLOGY, Issue 2004
M. Ciesla
Nase Chondrostoma nasus L., once one of the most common fish species in the upper reaches of central European rivers, is now considered endangered throughout its natural range. Since 2000 the Department of Ichthyobiology and Fisheries, Warsaw Agricultural University, has co-operated with the Polish Anglers Association in Krosno to study the effects of river restocking with pond-farmed nase juveniles. The experiment is carried out on Wislok River, where nase was very twenty years ago but has now completely disappeared. Selected parts of the river are stocked with tagged, one-summer and 1 year-old juveniles. Changes in nase occurrence, and their growth and foraging behaviour have been analysed. [source]