Ningirsu was associated with the yearly spring rains, a force essential to early irrigation agriculture.

The dam's primary purpose is to generate hydroelectricity, but it also provides water for irrigation agriculture.

The next stage occurred with the invention and creation of irrigation agriculture which was a large shift in this river valley.

External to the city, Sumerian irrigation agriculture created some of the first garden forms in history.

The statelets were characterized by a ruling class, slavery, irrigation agriculture, and emphasis on trade.

Its purpose is to provide water for irrigation agriculture.

The increased productivity of irrigation agriculture led to an increase in population and an added impact on resources.

During this period rich irrigation agriculture was developed: water sources, ditches and channels were constructed.

The first irrigation agriculture began about 4,500 years ago in the eastern Azerbaijan lowlands.

The water table of the latter is relatively high, making irrigation agriculture possible.