Sustainable shifting cultivation solutions

(Baonghean) - Before 2000, the area of ​​swidden fields in the province fluctuated from 100 to 120 thousand hectares each year. Currently, due to the State's management policy, propaganda, mobilization and mechanisms and policies to support production development through programs and projects, the swidden field has decreased sharply. The current swidden field area is about 50 thousand hectares, concentrated in the mountainous districts bordering Vietnam - Laos: Ky Son, Tuong Duong, Que Phong...

The lives of many ethnic minorities have been closely linked to slash-and-burn farming for generations, and the complete elimination of slash-and-burn farming is not yet possible at the present stage. Therefore, research to determine suitable, effective and sustainable slash-and-burn farming solutions is the responsibility of experts, managers at all levels and all people need to join hands to contribute.

According to the report of Nghe An Forest Protection Department, the whole province has 904,642.98 hectares of forest with a total forestry land area of ​​1,160,242.4 hectares, of which 737,762.72 hectares are natural forests, with a coverage of 54.6%. Nghe An forests and forestry land are mainly concentrated in 10 mountainous districts in the west of the province. To maintain coverage and provide income for people to stabilize their lives, reduce pressure on forest resources, for the planned swidden areas, the best solution is to apply combined agricultural and forestry cultivation.

Agroforestry is a harmonious combination of forestry and agricultural crops, cultivation and livestock on a land area. Agroforestry has many benefits: Intercropping many tree species on a forest area helps maintain vegetation, create and increase soil fertility, limit weeds, increase water infiltration and water retention, reduce erosion, surface runoff, limit floods in the rainy season and maintain water for the dry season, limit forest fires, contribute to sustainable ecological environment, limit pests and diseases of crops...

Combined agriculture and forestry in Tan Ky.

To effectively combine agriculture and forestry on sloping land, attention should be paid to the following issues:

Arrangement of planting strips: Most of the swidden land is sloping, so it is necessary to arrange planting strips along the contour to prevent water flow and limit topsoil erosion. Depending on the terrain, land conditions and investment capacity, if the swidden land is near a stream with a water source to irrigate crops in the dry season, planting strips can be arranged as follows:

Top strip (hilltop) 15-20m: Plant forestry trees with species that have been successfully planted locally such as: black star, dracontomelon, canarium, mahogany, lat, acacia, rosewood, egg-shaped oak, black muong (density 1,200 - 1,600 trees/ha)...

Next strip 2 - 3 m wide: Plant cover crops to improve the soil or drought-resistant grasses (pea, codonopsis, pagoda tree, wild peanut, mulato II grass, sudan...) to feed livestock (buffalo, cow, goat, horse, deer...).

Hillside section: Growing long-term industrial crops: longan, persimmon, lychee, mango, orange, lemon, tea, coffee, pepper....

At the bottom, food crops (beans, peanuts, corn, cassava, upland rice, vegetables, squash, melon, taro, cassava...) are grown and areas for livestock and poultry farms are used. If there are valleys, they can be converted to grow rice and fish ponds.

However, not all fields have the ideal conditions as above, most of them do not have irrigation water, so it is necessary to apply the measure of intercropping forestry trees and agricultural trees to support each other: Forestry trees are planted with a density of 500 - 600 trees/ha on the entire field area (only 1/2 of pure planting), planted in straight rows along the contour lines (rows are 5m apart, trees are 3m or 4m apart), the bare land strips between the 2 rows of forestry trees on the top of the hill are arranged to grow drought-resistant grass to prevent erosion and serve livestock; in the first 1-2 years, the slopes and foothills are intercropped with food crops (species that only wait for rainwater); when the planted forest has a ground surface shade of 30-40% (canopy cover of 0.3-0.4), the hillside is intercropped with medicinal plants under the forest canopy such as: Morinda officinalis, cardamom, ginger, turmeric, vetiver, kudzu...; The foothills can still be used for intercropping food crops, food crops, and squash. Because the forestry trees are planted sparsely, it is possible to intercrop agricultural crops and medicinal plants (shade-tolerant species) throughout the cycle until the time of forest exploitation. With this type of cultivation, forestry trees will grow very well thanks to the intercropping care process. The value of the planted forest is not only equal to but also higher than the normal density of 1,600 trees/ha because the product is large timber, not small timber or raw wood for paper fiber.

When choosing intercropping plants, you need to pay attention to the following principles:

This tree does not overwhelm, shade or secrete toxic substances, or harbor pests that can harm other trees; do not choose to plant strips of trees such as bamboo with fast-growing roots on the surface layer, absorbing a lot of water and nutrients in rice and corn fields, but should choose trees with nitrogen-fixing roots to improve the soil and prevent water flow; Master the characteristics and ecological requirements of the tree, its lifespan, planting techniques or planting experience (season, breeding, planting methods...).

The task of organizations and agricultural extension officers is to promote propaganda and mobilize people to effectively and sustainably cultivate the planned swidden areas: On the one hand, propaganda and education for people to fully understand the great value of forests, the preservation and protection of natural resources: Land, water resources, forest trees, raising awareness and knowledge for people about the harmful effects of slash-and-burn farming, disasters caused by deforestation and unscientific farming on sloping land causing climate change and consequences such as flash floods, landslides, water resource depletion...; propaganda and education on laws on forest protection, environmental protection, understanding of the State's policy in supporting people to produce sustainable agriculture and forestry on swidden land so that people voluntarily participate, gradually changing the practice of shifting cultivation, slash-and-burn farming, extensive seed sowing to intensive farming to increase productivity on swidden fields, integrated farming to increase land use value. Along with propaganda and mobilization of people, we build demonstration models of farming on sloping land in localities, organize tours of fixed farming models with high economic efficiency in different areas and for different ethnic groups; develop documents, train people on how to do it and help people "hear with their ears, see with their eyes, and do with their hands".

Nguyen Thi Ha

(Provincial Agricultural Extension Center)