Row of hand-dug trenches (GIZ, PASP)
This technique is designed to restore communal land on slopes and highland pediments. It involves manually excavating trenches 3 to 3.5 m long and 0.6 m deep, spaced 4 m apart in staggered rows. This results in around 625 trenches per hectare. The excavated earth is piled downhill of the trenches, which are aligned perpendicular to the slope. In the middle of each trench, a 0.40 m high step is left on which the tree seedling is planted. The tree receives the water it needs from the trench where it collects.
Purpose of the Technology: The main purpose of this technique is to restore tree cover on degraded, unfertile land and prevent water erosion on slopes by reducing the flow of water that threatens land downstream. The trenches reduce gully erosion and pedimentation of areas with a fragile soil structure. Like all afforestation measures, in the medium term, this technique is effective in protecting the land against water and wind erosion. The shade provided by the trees also lowers the temperature of the soil and the infiltration of water in the hand-dug trenches contributes to groundwater recharge.
Areas restored using hand-dug trenches can subsequently be exploited to a limited extent in accordance with strict controls.
Establishment / maintenance activities and inputs: The technique is very labour intensive. Work must begin immediately after harvesting when the soil is still moist and workable. A protection and monitoring system is required to ensure that grazing animals do not damage the young trees. The mortality of trees after planting is relatively high (survival rate is about 60%), and dead trees must be replaced systematically during the first three years. Good community organisation is required.
Natural / human environment: Hand-dug trenches are particularly useful when rainfall is low, as they retain water and make it available to the trees growing in them. In years when rainfall is abundant or there are violent downpours, the young trees are protected, as they are planted on a raised step within the trench, although there is a risk of flooding in the event of very heavy rain.
Местоположение: Regions of Tillabéri, Filingué, Ouallam, Téra and Tahuoa, Niger, Нигер
Число исследованных участков, где применяется Технология:
Пространственное распространение Технологии: равномерно-однородное применение на определенной площади
На постоянно охраняемой территории?:
Продолжительность применения Технологии: 10-50 лет назад
Тип внедрения/ применения
| Опишите затраты | Единица | Количество | Затраты на единицу (Доллары США) | Общая стоимость на единицу (Доллары США) | % затрат, оплаченных землепользователями |
| Оплата труда | |||||
| All the Labour | unit | 1,0 | 220,76 | 220,76 | |
| Посадочный материал | |||||
| Seedlings | unit | 1,0 | 41,55 | 41,55 | |
| Другие | |||||
| Transport of seedlings | unit | 1,0 | 1,93 | 1,93 | |
| Общая стоимость запуска Технологии | 264.24 | ||||
| Общие затраты на создание Технологии в долларах США | 264.24 | ||||
This technique permits the reintroduction of trees on degraded, unfertile land. Areas restored using hand-dug trenches can subsequently be exploited to a limited extent in accordance with strict controls.
