HEAT AND MOISTURE CONDITIONS IN THE PEAT AND MINERAL SOILS OF THE NORTHERN DVINA DELTA

It is shown that, for growing crops on the drained peat soils of north ern Russia in Europe, mixing sand with them and especially adding a la yer of sand on the surface have multiple beneficial effects on the pro perties of these soils as well as on the environmental conditions with in them. These measures have significantly improved temperatures in th e organogenic soils, raising temperatures in the surface horizons by 2 -4 degrees C in the growing reason, advancing the date of soil thawing in the spring (by as much as 15 days), and reducing the likelihood of surface frosts. A substantial improvement in crop yield was demonstra ted (especially for potatoes) as well as suppression of weeds in cover crops.