Agroforests set to replace monocrops in Northwest Viet Nam
Land degradation owing to monocropping is the main reason for reduced agricultural productivity in Northwest Viet Nam. But after four years of agroforestry research, results show positive signs for farmers.
Monocropping of annuals—such as maize, rice and cassava—has been identified as the main cause of soil degradation and reduction of yields in the mountainous northwestern provinces of Viet Nam. Wandering through any part of the Northwest will reveal hills bare to the top with rills created by erosion.
Farmers, especially poor farmers, have cultivated annual crops on sloping land for two reasons: first, annuals require less investment and; second, they bring annual returns. However, the farmers are not aware of the poverty trap of their own making. Because of the erosion caused by monocropping, the land’s fertility is reduced, which in turn leads to reduced productivity and incomes.
Mr Nguyen Duy Nang, who cultivates about one hectare in Co Noi commune, Son La province, said that he could harvest only four tonnes of maize in 2013, from which he earned about VND 15 million (± USD 700). Farmers from ethnic minorities, whose land is often steeper, produced even lower yields. A Thai farmer in Co Noi commune, Mr Leo Van Cuong, said he produced only two tonnes of maize per hectare while Mr Giang Giong Vu, an H’mong farmer in Tuan Giao commune, Dien Bien province, said he achieved only one tonne of rice per hectare. This is an extremely low rice yield compared to Viet Nam’s average of five tonnes per hectare.
The Agroforestry for Smallholders Livelihoods in Northwest Viet Nam (AFLI) project, which is funded by the Australian Centre for International Agricultural Research and the two CGIAR research programs: Forests, Trees and Agroforestry and Integrated Systems for the Humid Tropics, is developing best-practice agroforestry systems to provide farmers with more diverse sources of income while rehabilitating the environment.
At first, farmers were reluctant to change from monocropping annuals to agroforestry systems with long-term crops, such as coffee, fruit and timber. The reason was obvious: they feared they would have much lower income during the first few years.
‘It takes three years for coffee to produce cherries and four years for macadamia to bear fruit. For acacia or teak, we can only harvest after 7 to 11 years’, said Mr Leo Van Cuong.
Yet two years after AFLI’s trial plots were established on collaborating farmers’ land, the initial results showed a positive impact on reducing soil erosion and increasing farmers’ incomes. With the introduction of more trees and grass strips, soil erosion was reduced significantly. For example, in a complex agroforestry system with teak, plum, coffee, maize and fodder grass in Co Noi commune, there was almost no erosion. But just a few metres away at a control site, erosion was measured at 20 tonnes per hectare per year. In another system with acacia, longan, coffee, soybean, peanut and fodder grass in Tuan Giao commune, erosion was only 9 tonnes per hectare compared to 80 for monocropping maize.
Because short-term crops, such as maize and soybean, were intercropped with the newly planted trees, farmers still had income during the first few years. Additionally, farmers could reap two benefits from fodder grass: for feeding livestock and fish; and reducing erosion.
‘When I planted maize and rice, I earned about VND 10 million (± USD 465) per hectare per year’, said Mr Giang. ‘Now I am planting “son tra” [Ed: an indigenous fruit tree]. It is much higher value. Last year, I could sell at VND 30–50 000 (± USD 1.40–2.30) per kilogram. I think I may earn up to VND 50 million (± USD 2315) per hectare next year when the son tra is mature enough to produce fruit’.
More time is needed before researchers can measure the full impact of the new agroforestry systems on incomes because the farmers have not yet harvested the coffee, fruit and timber trees. Nevertheless, positive changes have been observed in farmers’ attitudes and behaviour. They are now more aware of the necessity to include more trees in their farming systems.
Mr Luong Van Hoi, a Thai farmer in Tuan Giao commune, Dien Bien province, said that, ‘I used to plant cassava and rice but, since 2011, cassava wouldn’t grow after a brick factory was built near my farm. So I changed to coffee. Acacia and longan are used as shade trees for the coffee and I can sell the longan fruit annually. In 2012–2013, I planted soybeans and peanuts when the coffee trees were small. I also planted grass to reduce soil erosion. I have to work much harder but I think it is a must when I want to earn more to send my children to school. I hope to be a good example so that my neighbours will follow’.
With such positive signs, it is hopeful that agroforestry will contribute to reduce erosion, improve incomes and enhance the quality of life of the farmers in Northwest Viet Nam.