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1.
Karl Maximilian Müller 《Forstwissenschaftliches Centralblatt》1928,50(6):177-192
Ohne Zusammenfassung 相似文献
2.
Schulte Maximilian Jonsson Ragnar Hammar Torun Stendahl Johan Hansson Per-Anders 《European Journal of Forest Research》2022,141(5):865-866
European Journal of Forest Research - 相似文献
3.
Schulte Maximilian Jonsson Ragnar Hammar Torun Stendahl Johan Hansson Per-Anders 《European Journal of Forest Research》2022,141(5):845-863
European Journal of Forest Research - Climate change mitigation trade-offs between increasing harvests to exploit substitution effects versus accumulating forest carbon sequestration complicate... 相似文献
4.
Frauke Kleemann Maximilian von Fragstein Barbara Vornam Annika Müller Christoph Leuschner Andrea Holzschuh Teja Tscharntke Reiner Finkeldey Andrea Polle 《European Journal of Forest Research》2011,130(5):707-716
Knowledge on phenological, morphometric, and phytochemical variation of local progenies of European aspen (Populus tremula, L.) is limited. The goal of this study was to characterize variation in growth and ecologically important leaf properties
in aspen full-sib families in relation to interacting organisms (mycorrhiza, endophytes, and insects) and to determine whether
these interactions were affected by soil application of a systemic fungicide. In local progenies, within-family variation
of neutral molecular genetic markers (nuclear microsatellites) was higher than between families. Significant variation in
growth, production of phenolic defensive compounds and other phytochemical leaf traits was found between families. Phenolic
compounds showed clear negative correlation with generalist herbivores, but did not result in negative trade-off with biomass
production. Differences in mycorrhizal colonization were not found among full-sib families and application of a systemic fungicide
suppressed neither mycorrhizal colonization nor infestation with insects. However, a strong suppression of endophytes occurred,
whose long-term consequences may require attention when fungicides are used in agroforestry plantations. 相似文献
5.
Maximilian Estevan Oliveira Jssica Campanholi Roberta Lima Cavalcante Felipe Silveira Moreno Edson Hideaki Yoshida Murilo Melo Juste Dini lvio Franco de Camargo Aranha Jos Carlos Cogo Lourdes Dias Stephen Hyslop Denise Grotto Valquíria Miwa Hanai‐Yoshida Yoko Oshima‐Franco 《Journal of Veterinary Emergency and Critical Care》2020,30(3):286-294
6.
Maximilian Wentzel Tim Koddenberg Holger Militz 《Wood material science & engineering》2020,15(4):223-228
ABSTRACT Eucalyptus nitens specimens were thermally modified under open and closed systems. The anatomical characteristics from selected modifications that presented similar mass losses were investigated by analyzing images taken from scanning electron microscopy, transmission light microscopy, and X-ray micro-computed tomography. Wood cell wall thickness, fiber, and lumen area were measured and compared to unmodified specimens, and the crack formation after modification was also analyzed. There was only a slight decrease in the measured characteristics when compared to unmodified specimens. The wood cell wall thickness was less affected than the fiber and lumen areas, and both modifications presented similar crack formations. Overall, there were no significant differences between open and closed system modifications in the anatomical structure. 相似文献
7.
Sediments deposited on road surfaces are contaminated with pollutants; the load of pollution increases from coarse to fine particles. When it rains, different fractions of the road-deposited sediments are washed off depending on the rain intensity, the slope of the catchment, and other site-specific factors. This road runoff is often treated using settling processes implemented in different types of manufactured treatment devices. These devices can be tested with well-defined artificial test materials to determine the removal efficiencies of particulate matter in a reproducible manner. However, the suitability of the currently deployed artificial test materials to represent the settling behavior of real runoff particle collectives is largely unknown. In this study, a laboratory method to measure and compare the settling behavior of artificial and real particle collectives with a reproducible particle size composition was developed. The particle collectives were obtained from different road surfaces, fractionated into sieve classes, and then recomposed into a defined particle size distribution that represented the road runoff. The settling velocity was analyzed in a modified settling column setup under constant conditions. The resulting data form a cumulative curve of the settling velocities for both artificial and real particle collectives. The main result from this work is that the tested artificial material and the recomposed real particle collectives have comparable settling behaviors despite different losses on ignition and densities. 相似文献
8.
Kopp EK Sieber M Kellert M Dekant W 《Journal of agricultural and food chemistry》2008,56(21):9828-9834
The carcinogen acrylamide (AA) is formed during the processing of food. AA is metabolized to mercapturic acids, which are excreted with urine. A hydrophilic interaction liquid chromatography tandem mass spectrometry method (HILIC-MS/MS) using a zwitterionic stationary phase (Zic-HILIC) was developed and validated to quantitate the mercapturic acids of AA (AAMA) and glycidamide (GAMA), and AAMA-sulfoxide in human urine. In contrast to reversed phases, the application of Zic-HILIC resulted in efficient retention and separation of these highly polar compounds. Off-line sample workup was avoided by application of column switching with a Stability BS-C17 trap column prior to the analytical column, thus minimizing interferences with the urinary matrix. Limit of quantification values (LOQs) were 0.5 microg/L (AAMA), 2.0 microg/L (AAMA-sulfoxide), and 1.0 microg/L (GAMA) in human urine. Median concentrations in urine samples ( n = 54) of six nonsmoking human subjects were 24.0 microg/L (AAMA, 7.8-79.8 microg/L), 16.7 microg/L (AAMA-sulfoxide, 6.8-70.1 microg/L), and 3.82 microg/L (GAMA, 1.0-23.6 microg/L). 相似文献
9.
The conversion of tropical forests to agricultural land use is considered as a major cause for a decline in soil organic carbon (SOC) stocks. However, the extent and impact of different land uses on SOC stock development is highly uncertain, especially for tropical Africa due to a lack of reliable data. Interactions of SOC with the soil mineral phase can modify the susceptibility of SOC to become mineralized. Pedogenic Fe‐, Al‐oxides and clay potentially affect SOC stabilization in highly weathered soils typically found in the humid tropics. The aim of our study was to determine the impact of different land uses on SOC stock on such soils. For that purpose, 10 pedologically similar, deeply weathered acidic soils (Acrisols, Alisols) in the Eastern Usambara Mountains (Amani Nature Reserve, NE Tanzania) under contrasting land use were sampled to a depth of 100 cm. The calculated mean SOC stocks were 17.5 kg C m?2, 16.8 kg C m?2, 16.9 kg C m?2, and 20.0 kg C m?2 for the four forests, two tea plantations, three croplands, and one homegarden, respectively. A significant difference in mean SOC stock of 1.3 kg C m?2 was detected between forest and cropland land use for the 0–10 cm depth increment. No further significant impacts of land use on SOC stocks were observed. All soils have a clearly clay‐dominated texture. They are characterized by high content of pedogenic oxides with 29 to 47 g kg?1 measured for the topsoils and 36 to 65 g kg?1 for the subsoils. No positive significant relationship was found between SOC and clay content. Statistically significant positive relationships existed between oxalate‐extractable Fe, Al, and SOC content for cropland soils only. Compared to data published in literature the SOC stocks determined in our study were generally high independent of the established land use. It appears that efficient SOC stabilization mechanisms are counteracting the higher disturbance regime under agricultural land use in these highly weathered tropical soils. 相似文献
10.
Anika Klotzbücher Klaus Kaiser Thimo Klotzbücher Maximilian Wolff Robert Mikutta 《植物养料与土壤学杂志》2019,182(4):570-577
The Hedley fractionation has become the preeminent measure for estimating the bioavailability of phosphorus (P) in soils. However, mechanisms underlying P extractability have never been tested. We hypothesize that P sequentially extracted by individual steps can either be referred to a specific mineral source (Hypothesis 1) or to its binding strength to minerals (Hypothesis 2). We prepared mineral‐P associations in the laboratory using various secondary mineral phases and P forms (orthophosphate, phytic acid, ribonucleic acid), which were then subject to the Hedley sequential extraction scheme (anion exchange resin in form, 0.5 M NaHCO3, 0.1 M NaOH, 1 M HCl, and concentrated HCl at 80°C). Extracts were analyzed for P as well as for the main mineral‐borne elements by inductively coupled plasma–optical emission spectroscopy (ICP–OES). In order to test if the observed mineral dissolution patterns match those of natural soils, we applied the Hedley fractionation to forest soils comprising various P stocks and measured in addition to extracted P also iron, aluminum, and calcium by ICP – OES. Phosphorus extractability from mineral‐P associations differed between P forms and mineral phases. Adsorbed P always contributed to several or all extracts, Hypothesis 1 was thus not tenable. Aluminum hydroxide, allophane, ferrihydrite, and goethite completely dissolved during Hedley fractionation from the third extraction step onwards. Successive mineral dissolution also occurred for the soil samples. Thus, extracted P represents partly desorbed P from various soil constituents and partly P co‐released upon dissolution of various minerals. Consequently, also Hypothesis 2 could not be confirmed, i.e., the sequential extraction is not suitable to assess different binding strengths between P forms and minerals. We conclude that the method hardly provides information for studies aiming at the mechanistic understanding of P bioavailability in soil. 相似文献