Gansu province lies on the loess plateau in central China. In this region, annual rainfall is highly variable with 60% of the annual rainfall occurring in the 3 months between July and September. Its average annual rainfall is about 300 millimeters. These factors have attributed to the poverty and Gansu is seen as one of the poorer areas of China. Traditionally, people of Gansu province have always depended on rainwater as a main source of water supply; excavation of 20 cubic meters clay lined underground cisterns in the loess soil for storing surface runoff is very common in this area. In dry years, however, these could not always provide sufficient water and people were forced to trek long distances to rivers or to depend on government water trucks.
The Gansu Research Institute launched 1-2-1 projects for water conservancy with the support of the provisional government. These projects were based on test trials, demonstrations and pilot projects carried out since 1988. Each family was provided with one clay tiled roof catchments area, two upgraded cement water cellars and plastic sheeting for concentrating rainwater runoff on one field. Traditional clay lined shuijiao (water cellars) were upgraded by lining them with cement or concrete and small metal pumps were attached to them. Proper tiled roof catchments and cemented courtyards replaced the bare earth catchments. A trench dug around this was used to collect any rainwater for watering the vegetables being produced. These simple, effective yet inexpensive, approaches by the project assisted over 200,000 families and ensured that around one million people was provided not only with sufficient water but also with good crop.
By 2000, a total of 2,183,000 rainwater tanks had been built with a total capacity of 73.1 million cubic metre in Gansu Province, supplying drinking water for 1.97 million people and supplementary irrigation for 236,400 ha of land.
Now buy viagra online from different online pharmacies and sort out all sexual performance related issues. You can get comprehensive and up to date source of drug information online. Not only Viagra, but you can buy cialis online also at some discounted price. From the site casino online also you can buy these.