Mekong Delta with prominent natural features in the world at nearly half the area flooded for 3-4 months each year, the major limitation for agriculture, causing difficulties for residential life. Exploitation and rational use of land and water resources is the core problem, affecting the economic efficiency and social and ecological environment protection in the Mekong Delta
Mekong Delta get fresh water from the Mekong River and rainwater. Both sources are characterized markedly seasonal. The average amount of water flowing through Mekong Delta Mekong over 460 billion m3 and 150-200 million tons transported sediment. The main volume of water and sediment in the course of long-term tonic made plain today.
Mekong Delta river systems, large and small canals interwoven, so very convenient year-round supply of fresh water. During the dry season from November to April, the Mekong River is the only water source. In rain, the average annual precipitation ranges from 2,400 mm in the western region to 1,300 mm Mekong Delta central region and 1,600 mm in the eastern region. In the flood season, usually occurs in September, river water flooding.
Hydrological regime of Mekong Delta has 3 features:
– Fresh juice and floods in the rainy season sediment transport, plankton, larvae.
-Water Salinity in coastal dry season.
-Water Acidic to alkaline soil in the rainy season.
Mekong Delta groundwater reserves are not large. Mining output is rated at 1 million m3 / day, mainly for water supply.
The total area of about 3.96 million hectares Mekong Delta, of which approximately 2.60 million ha is used for agricultural development and aquaculture accounted for 65%. In agricultural land, crop land accounts for over 50% annually, which is mainly on 90% of rice land. Land for growing crops and cash crops color day about 150,000 hectares of land occupied with perennial trees on 320,000 hectares, approximately 8.2% of the natural area.
Intertidal zone covers approximately 480,000 hectares, of which nearly 300,000 hectares capable seawater aquaculture, brackish water. According to the 1995 survey 0.508 million ha of forest land, of which 211 800 hectares of forest land and 296 400 ha of forest land. Forest coverage rate is only 5%.
The major soil groups in Mekong Delta include:
– Alluvial land (1.2 million ha): Focus on the center Mekong Delta. We have high natural fertility and no serious limiting factor yet. Many crops can be cultivated on this soil.
– ASS (1.6 million ha): Characterized by high acidity, aluminum toxicity levels and lack of nearby high potential. This group also includes land soils also including alkaline soils and moderate salinity. Of ASS concentrate in Dong Thap Muoi and Long Xuyen quadrangle alkaline soils are concentrated in the central region of Ca Mau peninsula.
– Soil salinity (0.75 million ha): Influenced by salt water during the dry season. Those prices can hardly be supplied fresh water. Currently rice is grown in the rainy season and in some areas it was shrimp in the dry season.
– Other land (0.35 million ha): including peatlands (U Minh forest area), gray on ancient alluvial soil (the northernmost of Mekong Delta) and hills (West-North Mekong Delta).
Overall in Mekong Delta very favorable for agricultural development without major restrictions. Due to soft ground, so to build industrial, transport and distribution of population, need reinforcement, fostering elevation, thus requiring much cos.