Productivity and conversion of sown grasslands in the plains area of Banat

The sown meadows, consisting of complex mixtures of grassland grasses and legumes species ensure a high level of production, a high quality of feed, an important source of biological nitrogen, which ensures the protein autonomy of the forage system. The paper highlights the influence of the structure of some perennial grasses and legumes, sown in the plains area, on the production of plant dry matter, on the use of the sown grassland, on the conversion into animal products and on the economic efficiency of the pratoecosystem in relation to animals. Carried out studies have shown that sown grasslands, consisting of a complex mixture (Lolium perenne 30 % + Festuca pratensis 30 % + Trifolium repens 20 % + Lotus corniculatus 20 %), in the plains area, used for grazing with sheep, obtains, in average, about 9 t/ha feed dry matter, over 3200 l/ha milk production and very high milk quality (5.5 % protein and 8.0 % fat). The research results showed an increase of sheep’s milk production in complex mixtures in both years of experience, compared to the mixture variant consisting only of grass species. The value of the quality indices of sheep's milk is higher, both in protein and fat, in the grazed variant, sown with a complex mixture of grasses and legumes, compared to the variant sown with only a mixture of grass species. In livestock farms, the complex sown grassland, consisting of several species of grassland grasses and legumes (multispecies) secures and makes the fodder system more efficient, ensuring both the constant increase of the feed value of the fodder and the increase of the quality indices of the animal products

Current Production Potential of Permanent Grasslands per Vegetation Areas and Altitudes (Caraş-Severin County, Romania)

Permanent grasslands in the Caraş-Severin County, Romania, cover, at present, 250,334 ha, i.e. 5.4% of the total grassland areas of the country. In this county, where grasslands represent 30% of the total area and 65% of the total agricultural area, permanent grasslands are important for the economy of the county both agriculturally, and socially and ecologically. Studies carried out show that the production potential of these grasslands varies between 8.51 and 13.14 ha of green matter; when applying complex mineral fertilisers, production increases three times and, when applying organic fertilisers, it increases two times. In general, after 500 m of altitude, green matter production decreases constantly with the increase of the altitude

Optimisation of the Start-up and Operation Regimes of Cooling Water Pumps of a High-Power Hydro Generator

It is necessary to make sure that the operation of cooling installations of hydro generators could be made in conditions of enhanced security so that the probability of defects occurrence during their exploitation be practically null. The asynchronous regime of direct network start up is accompanied by very high values of the start-up current, associated with important voltage drops on supply cables, which results in the extension of the motor starting time. The present paper shows an efficient method of driving the cooling water pumps by the supply of electric driving motors with variable frequency