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91.
92.
Gaßner 《Journal of pest science》1928,4(11):148-148
Ohne Zusammenfassung 相似文献
93.
K. Escherich Dr. H. Heßler J. D. Alfken Prof. Dr. F. Stellwaag 《Journal of pest science》1925,1(8):94-96
Ohne Zusammenfassung 相似文献
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Water and Solute Balances in Recultivated Lignite Mining Dump Soils-Field Data and Lysimeter Experiments 总被引:1,自引:0,他引:1
Knappe S. Haferkorn U. Mattusch J. Meißner R. Rupp H. Wennrich R. 《Water, air, and soil pollution》2004,157(1-4):85-105
Specific problems of water and solute balancing in the central German post-lignite-mining district are caused by the almost unknown interactions between surface water, seepage and groundwater in the unsaturated zone of mining dumps. This paper presents the findings of studies using lysimeter and seepage groundwater measuring systems designed to investigate the water balance and the migration of inorganic components in the vadose zone of recultivated dumps. Despite the heterogeneous tertiary layers of the three lysimeter monoliths studied, the quantity of seepage occurring at a depth of 3 m as well as the evapotranspiration and the soil water regime were almost the same in the 4 years of the investigation. The high variability of the ion balances in seepage reflects inhomogeneities in tertiary dump material and can be explained by substrate properties interacting with the soil's pH. Very high seepage conductivities are caused by coal containing high levels of pyrite with a low pH and high acid potential. These conductivities are caused by comparatively high concentrations of ions of sulphate, iron, aluminium, calcium, magnesium and heavy metals. The results confirm the impact of ventilated and pyrite-containing dump substrates for groundwater quality. 相似文献
98.
Anja Sänger Katharina Reibe Jan Mumme Martin Kaupenjohann Frank Ellmer Christina-Luise Roß 《Archives of Agronomy and Soil Science》2017,63(2):213-229
During the past years, most biochar studies were carried out on tropical soils whereas perennial field experiments on temperate soils are rare. This study presents a 3-year field experiment regarding the effects of differently produced biochars (pyrolyzed wood, pyrolyzed maize silage, hydrothermal carbonized maize silage) in interaction with digestate incorporation and mineral N fertilizer application on soil C and N, crop yields of winter wheat, winter rye and maize and the quality of winter wheat. Soil C and plant available potassium were found to be significantly positive affected by pyrolyzed wood biochar whereas the latter only in combination with N fertilization. Crop yields of winter wheat, winter rye and maize were not affected by biochar and showed no interaction effects with N fertilizer supply. Wheat grain quality and nutrition contents were significantly affected by biochar application, for example, highest amounts of phosphorus, potassium and magnesium were determined in treatments amended with pyrolyzed maize silage biochar. Biochar induced an improved availability of plant nutrients, which apparently were not yield limiting in our case. These results limit the potentials of biochar for sustainable intensification in agriculture by increasing crop yields for the temperate zones. However, detection of other environmental benefits requires further investigations. 相似文献
99.
Anne Gro Vea Salvanes 《Fisheries Research》1991,10(3-4):265-285
The present study analyses the selectivity for cod in two trammel-nets (three-wall nets) and one gillnet (single-wall net) used during an experimental cod fishery conducted monthly from october 1985 to December 1988 in a Norwegian fjord. It is part of a cod enhancement experiment conducted in the fjord. The three nets were grouped and utilized to sample the wild cod population. In addition, the gillnet and one trammel-net were utilized to sample a tagged group of cod with a known length composition. Relative selectivity curves were estimated indirectly for the two trammel-nets by comparing the catches of each length class within the length range 18–58 cm. Absolute selectivity curves were estimated directly for the gillnet and one trammel-net for the length range 15.0–22.0 cm. These were utilized to verify the indirectly estimated curves. The trammel-net selectivity curves obtained were used to provide an estimate for the true length-frequency distribution of cod in the fjord. Finally, it was tested whether a group of the three nets may be utilized as a unit effort to provide approximate random samples from the population. 相似文献
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