Structural basis
- Agri-silviculture system
It is defined as growing of trees and agriculture crops together in same lands at the same time. This system is common in all agro-ecological zones of Nepal, where agriculture crops are grown in terrace flat and trees are grown in terrace bunds, borders and slopes. Trees grown in different regions are Terai (Sissoo, Eucalyptus, Baikaino, Ipil IPil etc) hill (Mainly fodder trees such as Badahar, Tanki, Koiralo, Ipil-Ipil, Mulberry etc) and mountain (fodder trees such as Gogan, Dudhilo etc.
The main advantages of this system are as follows:
- Produce multiple products such as food/vegetables/fruits, fodder and forage needed for livestock, fuel wood, timber, and leaf litter needed for organic manure production.
- Improve and sustain the crop productivity which increases the level of income of the farmers.
- Improve the nutritive value of animal feed due to the supply of green fodder..
- This is also the best practice for soil nutrient recycling, which also helps to reduce chemical fertilizer purchase.
- Improve the farm site ecology by reducing surface run off, soil erosion and nutrient loss, gully formation and landslides.
- Improve the local micro-climate and enhance the productive capacity of the farm.
- Reduce pressure of community forests and other natural forests for fodder, fuel wood and timber.
- This practices helps for the beautification of the surrounding areas.
Inter cropping practices can also adopt in this system in plain areas where trees should be grown maintaining rows to rows distance (5 meters) and plant to plant distance (2-3 meters). Management operations such singling, pruning and thinning in timber species and lopping, coppicing and pollarding in fodder species should be applied to reduce shading effects of trees on agriculture crops.
2. Silvi-pastoral system
This system can be defined as growing of trees and grasses or forage species together in same lands at the same time. This system is common in all agro-ecological zones of Nepal, where land is marginal for crop production. In mid-hilly region, land having grasses is known as kharbari. Trees grown in Kharbari in different regions are Terai (Sissoo, Eucalyptus, Ipil Ipil etc) hill (Mainly fodder trees such as Badahar, Tanki, Koiralo, Ipil-Ipil etc and timber species like Chilaune) and mountain (fodder trees such as Gogan, Dudhilo, Khasru etc.
The main advantages of this system are as follows:
- Produce multiple products such as fodder and forage needed for livestock, fuel wood, timber, and leaf litter needed for organic manure production.
- Improve and sustain the livestock productivity which increases the level of income of the farmers.
- Improve the nutritive value of animal feed due to the regular supply of green fodder.
- This is also the best practice for soil nutrient recycling, which also helps to reduce chemical fertilizer purchase.
- Improve the farm site ecology by reducing surface run off, soil erosion and nutrient loss, gully formation and landslides.
- Improve the local micro-climate and enhance the productive capacity of the farm.
- Reduce pressure of community forests and other natural forests for fodder, fuel wood and timber.
- This practices helps for the beautification of the surrounding areas.
3. Agri-silvi-pastoral system
Growing of trees, agriculture crops and grasses together in same lands at the same time is known as agri-silvi-pastoral system. This is a typical hill farming system of Nepal, in which agriculture crops are grown in terrace flat, trees in terrace bunds, border and slopes and grasses in terrace slopes, and some farmers have been growing improved legume and non-legume grasses such as Mott napier (Pennisetum purpureum), Setaria (Seteria splendida), Mulato (Brachiaria brizantha x B. ruziziensis) and Forage peanut (Arachis pinotoi) along terrace bunds and borders.
The main advantages of this system are as follows:
- Produce multiple products such as food/vegetables/fruits, fodder and forage/grasses needed for livestock, fuel wood, timber, and leaf litter needed for organic manure production.
- Improve and sustain the crop productivity which increases the level of income of the farmers.
- Improve the nutritive value of animal feed due to the supply of green fodder.
- This is also the best practice for soil conservation and soil nutrient recycling, which also helps to reduce chemical fertilizer purchase.
- Improve the farm site ecology by reducing surface run off, soil erosion and nutrient loss, gully formation and landslides.
- Improve the local micro-climate and enhance the productive capacity of the farm.
- Reduce pressure of community forests and other natural forests for fodder, forage/grasses, fuel wood and timber.
- This practices helps for the beautification of the surrounding areas.
4.Horti-silviculture system
This system is defined as growing of trees and fruit trees or ornamental trees or vegetables/flower together in same lands at the same time. This system is common in Terai and Inner Terai of Nepal, where trees such as Sissoo, Eucalyptus, Baikaino, Ipil IPil etc are grown around fruit orchard that act as shelter belt.
In eastern Nepal, cardamom is planted as an under storey with Uttis (Alnus nepalensis) trees. Similarly, Siris and Sissoo trees are planted for providing shade to tea, and Ipil Ipil is the best trees for providing shade to coffee plants.
The main advantages of this system are as follows:
- Produce multiple products such as fruits, fodder and forage needed for livestock, fuel wood, timber, and leaf litter needed for organic manure production.
- Improve and sustain the fruit/vegetable productivity which increases the level of income of the farmers.
- This is also the best practice for soil nutrient recycling, which also helps to reduce chemical fertilizer purchase.
- Improve the farm site ecology by reducing soil erosion and nutrient loss.
- Improve the local micro-climate and enhance the productive capacity of the farm.
- This practices helps for the beautification of the surrounding areas.
5. Agri-horti-silviculture
This system is defined as growing of agriculture crops, trees and fruit trees or ornamental trees or vegetables/flower together in same lands at the same time. This system is common in home gardens of mid-hills, Terai and Inner Terai of Nepal, where fodder trees such as Badahar, Tanki, Ipil Ipil etc and timber and fire wood species such as Sissoo, Eucalyptus, Baikaino, etc are grown around fruit orchard that act as shelter belt, and agriculture crops such as maize, ginger, turmeric, yam, colocassia and vegetables are grown under fruit trees.
The main advantages of this system are as follows:
- Produce multiple products such as food, fruits, fodder and forage needed for livestock, fuel wood, timber, and leaf litter needed for organic manure production.
- Improve and sustain the livelihoods of farmers by increasing the level of income through the sale of fruit/vegetables.
- Trees grown around fruit gardens also provide extra-income.
- This is also the best practice for soil nutrient recycling, which also helps to reduce chemical fertilizer purchase.
- Improve the farm site ecology by reducing soil erosion and nutrient loss.
- Improve the local micro-climate and enhance the productive capacity of the farm.
- This practices helps for the beautification of the surrounding areas.
6. Silvi-fishery or aqua-silviculture
Growing of trees around fish pond is known as silvo-fishery or aqua-silviculture. In this system, trees and fruit trees are being planted along the embankment of the fish pond. This system is popular in Terai and inner-Terai of Nepal, where trees and fish included in the same system.
Tree species grown along the embankment of fish pond are Sissoo, Eucalyptus, Bakaino, Ipil-ipil etc and fruit species are Banana, Papaya and Pineapples.
Some farmers also included duck and pigs in aqua-silviculture systems. The main advantages of this system are as follows:
- Produce multiple products such as fish, fruits, fodder, fuel wood, timber, and leaf litter.
- Improve and sustain the fish and fruit productivity which increases the level of income of the farmers. Extra income can also be generated from trees, fruits ducks and pigs.
- Improve the farm site ecology by reducing soil erosion and nutrient loss.
- Improve the local micro-climate creating cool environment to fish during summer season.
- This practices helps for the beautification of the surrounding areas.
- Leaves, flowers, and fruits fallen into the fish pond can provide food to fish.
7. Apiculture
- This is combination of trees and bees.
8. Sericulture
Growing of mulberry trees for silk production is known as sericulture, in which mulberry leaves are used to feed the silk worm at larva stage for the production of silk. The cocoon of the silk worm is harvested for reeling the silk.
The main agroforestry systems under temporal arrangement of the different components are shifting cultivation and Taungya agroforestry practices. In these systems, agriculture crops are grown for few years (2-3 years), and then Taungya agroforestry plot developed as forest and shifting cultivation areas left as degraded lands. In some hilly districts of Nepal, such degraded forest lands have been handed over to Leasehold Forest User Groups (LFUGs) as leasehold forests.
9. Shifting cultivation
This is a low input agriculture practice and fallow management which is common practice in Asia. This system also know as slash and burning agriculture, in which forest land is cleared through cutting and burning for agriculture. In this system, few big trees are left as such for shade and for fruits or fodder, and because they are big to remove. Ash is scattered after trees and leaf litter have been burned to fertilize the land. Little fertilizer and manure is added apart from the ash, and therefore, agriculture crops are grown for few years.
After clearing the forest lands, farmers carry out tillage operation and land preparation, and then sow crop seeds.
Generally, farmers grow agriculture crops in such lands having low level soil fertility for 2-3 years, and with high level of soil fertility of flat lands for 7-10 years. When crop production decreased due the lack of plant nutrients into the soil, farmers move to another areas and then start to continue same practice of agriculture.
Advantages of shifting cultivation
- Weed control.
- Easy methods for clearing forest lands for agriculture.
- Suitable for root crops, and crops like banana.
- Farmers get food, fruits and income.
- It also gives employment opportunity for farmers for short period.
Disadvantages of shifting cultivation
- Heavy deforestation
- Increase soil and soil nutrient loss.
- Soil nitrogen will be lost by burning.
- Low input in long run.
- Soil erosion occurs in sloppy areas.
- Biodiversity lost due to burning and tillage operations.
- Silt eroded from shifting cultivation areas will be accumulated in low lying areas.
- Land degradation and other environmental problems increased.
10. Taungya agroforestry
Taungya is Burmese words which means (Taung = hill and ya = cultivation) hill cultivation. But this system is well adopted in plain areas of Myanmar, Bangladesh, India and Nepal. In 1850s, Burma has established a teak plantation using Taungya method of agroforestry, in which poor farmers (shifting cultivators) were given teak plantation areas for agriculture crop production.
This practice also adopted by India in West Bengal in 1890s, where shifting cultivators were given plantation areas for agriculture crop production until tree canopy closed. After that farmers were shifted in another area.
This practice consists of land preparation, tree planting and growing of agriculture crops for 2-3 years until the shade become too dense. In some areas, crops were grown one year before tree planting.
Types of Taungya
We can found 3 types of Taungya agroforestry systems that are Departmental Taungya, Institutional Leased Taungya, and Village Taungya.
a) Departmental Taungya
Under this, plantation is established by the forest department giving plantation areas to farmers to grow agricultural crops. The main aim of raising agriculture crops along with the plantation is to keep along with the land free of unwanted vegetation.
b) Institutional land Leased Taungya
The institutional lands is given on lease to the person who are interested to grown agriculture crops for a specialized number of years by ensuring the care of tree plantation.
c) Village Taungya
In India, this is the most successful of all the three Taungya systems. Under this the people who have settled down in a village inside the forest for this purpose to raise crops. Usually each family has about 0.8 to1.7 ha of land has raise trees and cultivate crops for 3 to 5 years.
In Nepal, Departmental Taungya system has been started in 1972 at Tamagadhi of Bara district, which was encroach by migrants from the hills. To protect remaining forests from encroachment, the Taungya system of agroforestry was practiced. After that Terai Community Forestry Development Project and Sagarnath Forestry Development Project have also practiced this system in large scale from 1983 to 1992. These projects have given plantation areas (generally 1 ha for one family) for poor farmers living around the plantation sites for 5 years on lease to grow agriculture crops with out any damage to trees.
Advantages of Taungya agroforestry
- High tree growth and survival rate due to the care and addition of organic matter into the soil by Taungya farmers.
- Problems of unemployment are reduced for short time.
- Maximum utilization of plantation areas.
- Low cost methods for plantation establishment (weeding costs and protection costs reduced).
- Fire hazard reduced.
- Food crops obtained from plantation areas.
- Weeds and tree climbers controlled.
- Some farmers have generated income form the sale of vegetables grown in plantation areas.
- People’s participation in plantation establishment and management increased.
- Easy for the formation of community forest user groups.
- Good relation of forestry field staff with local farmers.
Disadvantages of Taungya agroforestry
- Danger of epidemics diseases to both trees and crops due to agriculture practices. Both trees and agriculture crops work as alternative hosts to insects, pests and diseases.
- Loss of soil nutrients due to the exposure of soils.
- Legal problems- famers don’t want to left the land. This is now big problem in Sagarnath Forestry Development Project.
- Susceptibility of lands to accelerated soil erosion in sloppy areas due to the cultivation practices to grow agriculture crops.
- Damage to young trees during tillage operation.