Abstract: Energy budget of the water body of the Nanhu lake in Changchun city was studied at ecosystem level.The water surface received 4969635.4kJ穖^-2radiant energy annually,which was used to conduct the physical and biological reactions in the lake,as well as the energy exchanges with surroundings.Loss by evaporation amounted to 55.9% of the total radiant energy received by the lake body,with reflection 17.8%,exchange with atmosphere 14.0%,increase of water temperature 6.6%,ice melting 4.9%,primary production 0.6%,and exchange with bottom 0.2%.Finally, the energy budget of the Nanhu Lake was compared with other water bodies.

Key words: winter wheat with strong gluten, irrigation, grain yield, grain quality, glutenin macropolymer (GMP).