Trends in structure, plant growth, and microorganism interrelations in the soil

Increased demand for food production, extensive agricultural cultivation, and destructive processes occurring naturally in soil (erosion, weathering) will necessitate use of lower quality soils, thus promoting the use of soil conditioners. In order to draw attention to the unforseen and possibly hazardous effects of soil conditioners along with their positive effects, a laboratory experiment with two anionic polyacrilamide (PAM) polymers was conducted at three application levels and on three soil types. It was found that these PAMs harmed, improved, or barely affected sandy, loamy, and clay soils, respectively. The applied PAMs drastically affected soil physical properties, e.g., aggregates size distribution and water retention, thus affecting plant production above and below the soil surface. Only a semi-systematic response of the nematodes, bacteria, fungi, and actynomicetes population to the above treatments was found.