Reducing of nutrient leaching with ecological land management?

The paper describes long term lysimeter tests about the influence of land use changes on water balance and budget of material ( especially N and P). lt has been shown that converting of previously farmed heavily lysimeters into forms of ecological land management practices without fertilization and irrigation does not lead directly to a reduction of nutrient leaching. The potatoes in an ecological crop rotation were not able to absorb the mineralized nitrogen from clover after plowing.