The most important consequence of land degradation in Vietnam is the loss of productivity, depletion of fauna and flora and reduction of agricultural land per capita .In terms of the estimated monetary loss on account of land degradation, water erosion and leaching accounted for more than half, salinisation, acidification, drought and water logging for about one third and decline in soil fertility for the rest.
The consequences of flood inundation and water logging are very serious on humans and precious natural resources. For example, two floods in 1999 occurred in the southern central coast claimed 711 lives and caused economic loss estimated at more than US$ 235 million. Besides, millions of tons of soil from the hilly and mountainous regions was eroded and flowed into rivers, streams, plains and the sea.
Frequent droughts directly influence the soil moisture and its thermal regime, performance, destruction and accumulation of organic matters, changing structure of soil aggregates and soil organo-mineral complex. The more serious effect is on the survival and development of the soil community due to the destruction of biological activity and depletion of soil productivity.
Soil salinisation and acidification are major threats to the development of sustainable agriculture over a large area of 3.0 million hectares, particularly in the Mekong River delta, northern and central coast of Vietnam.
Another estimate of economic loss caused by land degradation is placed at least US$ 700 million due to traditional cultivation practices such as shifting and extensive cultivation (approximately adopted in the total area of 2.6 million ha), in comparison with those in the same area of undegraded land.
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