Long-term tillage system effects under moist cool conditions in Switzerland     

Thomas Anken  Peter Weisskopf  Urs Zihlmann  Hansrudolf Forrer  Jan Jansa  Katarina Perhacova 《Soil & Tillage Research》2004,78(2):171-183

How do different soil tillage systems influence soil quality over the years? Under moist cool conditions is it possible in the long term to reduce dramatically soil tillage intensity without experiencing reductions in yield or other problems? In 1987, the Swiss Federal Research Station for Agricultural Economics and Engineering in Tänikon initiated a long-term soil tillage trial to clarify these questions. The trial compared mouldboard plough, chisel, paraplow, shallow tillage and no-tillage systems on a well-drained Orthic Luvisol with 160 g kg⁻¹ clay, 310 g kg⁻¹ silt, and under a climate that has a mean annual precipitation of 1180 mm. The tillage treatment effects were evaluated by measuring several biological, chemical, and physical soil quality indicators. Reduced soil tillage increased earthworm populations, reduced Pseudocercosporella herpotrichoides infection in wheat (Triticum aestivum) and increased plant colonisation by arbuscular mycorrhizal fungi. Yields for no-tillage and other ploughless cultivation techniques were on par with those obtained by ploughing. An exception was direct-drilled maize (Zea mays), where no-tillage decreased yield by more than 10% over the course of 14 years. In the first 7 years of the trial, the level of soil organic carbon in all the tillage regimes was approximately 40% lower than natural grassland (initial situation 1987=75 Mg SOC ha⁻¹). The no-tillage method did not differ from the others in respect of bulk density, but it showed an increased preconsolidation stress and hence better trafficability. Under Switzerland’s moist cool climatic conditions, it is possible to reduce soil tillage intensity without substantial reductions in yield, and at the same time improve soil quality.  相似文献   

Concentration and molecular weight distribution of dissolved organic carbon in a mangrove creek in the Hinchinbrook area,Australia   总被引：1，自引：0，他引：1  

Mueller  Hansrudolf  Ayukai  Tenshi 《Mangroves and Salt Marshes》1998,2(4):231-235

The concentration and molecular weight distribution of dissolved organic carbon (DOC) are reported for a mangrove creek in the Hinchinbrook area, Australia. DOC concentration ranged from 1.0mg Cl–1 near the creek mouth to 2.2mg Cl–1 at the innermost part of the creek. There was no apparent spatial trend in molecular weight distribution of DOC, with a >300gmol–1 fraction accounting for about 70% of the total in all samples. DOC concentration fluctuated between 0.5 and 1.2mg Cl–1 over one tidal cycle. The samples collected at low tide and during the rising tide were dominated by DOC of >300gmol–1 and <300gmol–1, respectively. This suggested the export of high molecular weight DOC, probably originating from litter leachates, and the import of low molecular weight DOC to the creek.  相似文献