Synthetic resampling strategies and machine learning for digital soil mapping in Iran     

Ruhollah Taghizadeh‐Mehrjardi  Karsten Schmidt  Kamran Eftekhari  Thorsten Behrens  Mohammad Jamshidi  Naser Davatgar  Norair Toomanian  Thomas Scholten 《European Journal of Soil Science》2020,71(3):352-368

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Regional and local scale variations in soil organic carbon stocks in West Greenland     

Philipp Gries  Karsten Schmidt  Thomas Scholten  Peter Kühn 《植物养料与土壤学杂志》2020,183(3):292-305

The soil organic carbon (SOC) pool of the Northern Hemisphere contains about half of the global SOC stored in soils. As the Arctic is exceptionally sensitive to global warming, temperature rise and prolonged summer lead to deeper thawing of permafrost‐affected soils and might contribute to increasing greenhouse gas emissions progressively. To assess the overall feedback of soil organic carbon stocks (SOCS) to global warming in permafrost‐affected regions the spatial variation in SOCS at different environmental scales is of great interest. However, sparse and unequally distributed soil data sets at various scales in such regions result in highly uncertain estimations of SOCS of the Northern Hemisphere and here particularly in Greenland. The objectives of this study are to compare and evaluate three controlling factors for SOCS distribution (vegetation, landscape, aspect) at two different scales (local, regional). The regional scale reflects the different environmental conditions between the two study areas at the coast and the ice margin. On the local scale, characteristics of each controlling factor in form of defined units (vegetation units, landscape units, aspect units) are used to describe the variation in the SOCS over short distances within each study area, where the variation in SOCS is high. On a regional scale, we investigate the variation in SOCS by comparing the same units between the study areas. The results show for both study areas that SOCS are with 8 kg m^?2 in the uppermost 25 cm and 16 kg m^?2 in the first 100 cm of the soil, i.e., 3 to 6 kg m^?2 (37.5%) higher than existing large scale estimations of SOCS in West Greenland. Our approach allows to rank the scale‐dependent importance of the controlling factors within and between the study areas. However, vegetation and aspect better explain variations in SOCS than landscape units. Therefore, we recommend vegetation and aspect for determining the variation in SOCS in West Greenland on both scales.  相似文献   

Responses of surface SOC to long‐term experimental warming vary between different heath types in the high Arctic tundra     

Ji Young Jung  Anders Michelsen  Mincheol Kim  Sungjin Nam  Niels M. Schmidt  Sujeong Jeong  Yong‐Hoe Choe  Bang Yong Lee  Ho Il Yoon  Yoo Kyung Lee 《European Journal of Soil Science》2020,71(4):752-767

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Sectional notes     

J. H. Heckman  H. G. Zuckerman  C. H. Metzger  W. B. Ward  John S. Gardner  Frank W. Hussey  Ralph W. Donaldson  A. G. Tolaas  K. H. Fernow  E. V. Hardenburg  W. G. Been  Robert Schmidt  E. M. Gillig  E. B. Tussing  K. W. Lauer  K. H. Klages  Brooks D. Drain  H. L. Bailey  J. G. Milward 《American Journal of Potato Research》1935,12(7):196-204

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Sectional notes     

J. H. Heckman  H. G. Zuckerman  C. H. Metzger  B. A. Brown  E. R. Bennett  W. B. Ward  C. L. Fitch  O. H. Elmer  Jhon S. Gardner  Julan C. Miller  Frank W. Hussey  E. L. Newdick  Ralph W. Donaldson  Lionel Harris  H. O. Werner  Wm. H. Martin  E. V. Hardenburg  T. E. Odland  Robert Schmidt  Geo E. Prince  Brooks D. Drain  Harold L. Bailey  G. S. Ralston  Chase D. Gaines  J. G. Milward  John Tucker 《American Journal of Potato Research》1935,12(6):158-170

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Die Wei?tanne in Ostfriesland     

G. D. Schmidt 《Forstwissenschaftliches Centralblatt》1951,70(11):641-665

Ohne ZusammenfassungMit 4 Abbildungen  相似文献   

Pseudomonacidal activity of phenolic disinfectants in hard water     

M Winicov  W Schmidt  M Palochak 《Journal of the Association of Official Analytical Chemists》1974,57(4):880-884

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Bemerkung zur Lebensweise der Larve vonMalachius bipustulatus L. (Malacodermata,Telephoridae)     

Dr. H. Schmidt 《Journal of pest science》1944,20(1-3):10-12

Ohne Zusammenfassung Mit 3 Abbildungen  相似文献   

Disturbance‐induced responses of VHF and satellite tagged harbour seals          下载免费PDF全文

Signe M. Andersen  Jonas Teilmann  Rune Dietz  Niels M. Schmidt  Lee A. Miller 《水产资源保护:海洋与淡水生态系统》2014,24(5):712-723

Structure-activity relationships of triazinone herbicides on resistant weeds and resistant Chlamydomonas reinhardtii     

Walter Oettmeier  Ursula Hilp  Wilfried Draber  Carl Fedtke  Robert R. Schmidt 《Pest management science》1991,33(4):399-409

Weeds resistant to the s-triazine herbicide atrazine also show resistance to the triazinone herbicide metribuzin. However, with highly lipophilic triazinones, thylakoids isolated from atrazine-resistant Amaranthus retroflexus (mutation at position Ser₂₆₄ of the photosystem II D-1 reaction centre protein) in general show a higher pI₅₀ value in photosystem II electron transport than those from the wild type (i.e. negative cross-resistance; ‘supersensitivity’). A quantitative structure–activity relationship (QSAR) can be established, wherein the lipophilicity of the compound plays a major role. In in-vivo experiments, it was found that the triazinone DRW2698 killed resistant Amaranthus retroflexus and Chenopodium album whereas the wild type was almost unaffected. Triazinones were further investigated in five different mutants of Chlamydomonas rheinhardtii (mutations in the D-1 protein at positions Ser₂₆₄, Ala₂₅₁, Leu₂₇₅, Phe₂₅₅, and Val²¹⁹). Inhibitory activity of all triazinones was generally enhanced in the Phe₂₅₅ mutant but decreased in the Val₂₁₉ mutant. In the other mutants, biological activity was decreased when position 3 of the triazinone was substituted by CH₃, OCH₃, SCH₃, NHCH₃ or N(CH₃)₂. However, negative cross-resistance was again observed when this position was occupied by free thiol. It is therefore suggested that these two groups of triazinones orient themselves differently within the herbicide binding niche of the photosystem II D-1 protein.  相似文献