A. Levakovi und Hans Muggenthaler 《Forstwissenschaftliches Centralblatt》1927,49(15):555-560

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Pinus sylvestris L., Die gemeine Kiefer     

Dr. Peter Karl Schott 《European Journal of Forest Research》1904,26(8-9):436-449

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Hans Schwarz 《Forstwissenschaftliches Centralblatt》1931,53(5):184-185

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Forstmeteorologische Messungen in einem Eichenbestand     

Rudolf Geiger und Hans Amann 《Forstwissenschaftliches Centralblatt》1931,53(10):341-351

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Pyrene and nile red fluorescence probes for in‐situ study of polarity and viscosity of soil organic coatings implicated in soil water repellency     

Helen M. Balshaw  Peter Douglas  Matthew L. Davies  Stefan H. Doerr 《European Journal of Soil Science》2020,71(5):868-879

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System for quasi‐continuous simultaneous measurement of oxygen diffusion rate and redox potential in soil     

Ren Reiser  Viktor Stadelmann  Peter Weisskopf  Lina Grahm  Thomas Keller 《植物养料与土壤学杂志》2020,183(3):316-326

Oxygen diffusion rate (ODR) and redox potential (E_H) are quantitative indices representing oxygen availability and redox status in soils, which is valuable information for better understanding causes and effects of soil aeration. Because these indices are spatially and temporally highly variable, continuous measurements and adequate numbers of repetitions are essential for accurate in situ monitoring. Here, we present a new, fully automated recording system for in situ measurements where ODR and E_H are measured at the same platinum electrode. The conflict between electrode polarization for ODR and the resulting biased E_H readings is solved by reducing the polarization time and introducing a recovery interval between two consecutive measurement cycles. The shorter polarization time ensures accurate E_H readings. It also results in moderately overestimated ODR readings, but this can be corrected before data analysis. The recovery interval restricts temporal resolution of the E_H‐ODR data pairs to 8 h. We illustrate the use of the system with measurements in a field experiment in Zürich, Switzerland. ODR curves at different depths ran roughly parallel to the corresponding curves of O₂ concentration in soil air but ODR was much more sensitive to precipitation. Low ODR was a necessary but not a sufficient condition for declining E_H. E_H ran parallel to O₂ concentration in soil air rather than to ODR. The fully automated system allows for time series of replicate measurements in multifactorial field studies with reasonable labor requirements. It may be particularly suitable for studies examining the effects of soil tillage, compaction, and irrigation, where structure‐related soil properties such as porosity, gas permeability, and soil aeration play a dominant role.  相似文献   

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   

Rassen der gemeinen Kiefer     

Peter Karl Schott 《Forstwissenschaftliches Centralblatt》1907,29(4):199-218

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Hans J. Kamp 《Journal of pest science》1951,24(6):85

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New lease of life for Darwin's giant tortoises,Galápagos Islands     

Peter F.R. Jackson 《Biological conservation》1974,6(1):63-64

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