Soil is one of the most important natural resources to suffer as a result of trees cutting. Obviously all agroforestry systems have effects and influences upon the soil. Agroforestry technologies that have potential applicability to improve soil fertility, soil conservation, soil physical properties, and use of shelter belts and wind breaks.

1. Plantation of compatible and desirable species of woody perennials on farmland results in an improvement in soil fertility.

1. Increase in the organic matter content of the soil through the addition of leaf litter and other plant parts;
2. More efficient nutrient cycling within the system and consequently more efficient utilization of nutrients that are either inherently present in the soil or externally applied;
3. Increase in the plant cycling fraction of nutrients, with a resultant reduction in the loss of nutrients beyond the nutrient-absorbing zone of the soil;
4. Enhanced nutrient economy because of different nutrient absorbing zones of the root systems of the component species.

2. Inclusion of trees and woody perennials on farmlands can, in the long run, result in marked improvements in the physical conditions of the soil in permeability water-holding capacity, aggregate stability and soil temperature regimes. Although these improvements may be slow, their net effect is a better soil medium for plant growth.
3. The role of trees in soil conservation and erosion control is one of the most widely acclaimed and compelling reasons for including trees of farmlands prone to erosion hazards. The beneficial effects of trees in this regard extend beyond protecting the immediate farmland under consideration, to impart stability to the ecosystem and reducing the rate of siltation of downstream aquatic ecosystem, dams and reservoirs.

Combining trees with food crops on cropland farms yield certain important environmental benefits include:

i) Reduction of pressure on forest.

ii) More efficient recycling of nutrients by deep-rooted trees on the site.

iii) Better protection of ecological systems.

4. Reduction of surface run-off, nutrient leaching and soil erosion through impeding effect of tree roots and stems on these processes.

5. Improvement of microclimate, such as lowering of soils surface temperature and reduction of evaporation of soil moisture through a combination of mulching and shading. Increment in soil nutrients through addition and decomposition of litter-fall.
6. Improvement of soil structure through the constant addition of organic matter from decomposed litter.

1. Improvement of soil moisture-retention in rain-fed cropping systems and pastures through improved soil structure and microclimatic effects of trees.
2. Regulation of stream flow for reduction of flood hazard and more even supply of water,through reduction of run-off and improvement of interception and storage in infiltration galleries, through various watershed protection practices involving trees.

3. Improvement of drainage from water logged or saline soils by phrea-tophytic trees.

4. Increased biomass storage of waster for animal consumption in forage and fodder trees(higher water content of tree fodder in dry season).

Ag.
Technologies
(Agro Forestry)