Some investigations in precision agriculture.

A brief review of the current situation and activities in precision agriculture in Latvia are given. In the latest years investigations are carried out in directions: yield and weedy monitoring; monitoring of soil properties and its changes; ecological grain drying with microclimate monitoring and distance control; impact of the plough body parameters on the ploughing efficiency, criteria determination for efficiency estimation of agricultural machinery in field crop cultivation; impact of the soil humidity on the ploughing resistance. The use of computerised ventilated bins for drying and storing grain is purposeful in the organisational, as well as economical and ecological aspects. It facilitates the farmer to organise the harvesting process, to use favourable weather conditions to a full extent, to obtain a higher-quality product and sell it on more profitable terms. Minimum fuel consumption and costs can be achieved by aggregates completed with efficient up-to-date tractors and tillage machines that are suitable for local conditions and have optimal design and applications parameters, improving the tractor loading and aggregation patterns. Humidity most of all impacts the soil hardness and cutting resistance which considerably dominates in the summary resistance of the plough body. An increase in the soil humidity leads to a decrease in the ploughing resistance that is more remarkable on clay soils.