Agroforestry - What is it?

The theoretical base for agroforestry comes from ecology, via agroecology. From this perspective, agroforestry is one of the three principal land-use sciences. The other two are agriculture and forestry. The efficiency of photosynthesis drops off with increasing light intensity, and the rate of photosynthesis hardly increases once the light intensity is over about one tenth that of direct overhead sun. This means that plants under trees can still grow well even though they get less light. By having more than one level of vegetation, it is possible to get more photosynthesis than with a single layer. Agroforestry has a lot in common with intercropping. Both have two or more plant species (such as nitrogen-fixing plants) in close interaction, both provide multiple outputs, as a consequence, higher overall yields and, because a single application or input is shared, costs are reduced. Beyond these, there are gains specific to agroforestry. Agroforestry is also defined as the deliberate land management unit whereby, woody perennials are deliberately grown on same piece of land along with agricultural crop and or livestock in some form of spatial arrangement or temporal sequence. Agroforestry systems can be advantageous over conventional agricultural, and forest production methods. They can offer increased productivity, economic benefits, and more diversity in the ecological goods and services provided. Biodiversity in agroforestry systems is typically higher than in conventional agricultural systems. With two or more interacting plant species in a given land area, it creates a more complex habitat that can support a wider variety of birds, insects, and other animals. Depending upon the application, potential impacts of agroforestry can include:

•  Reducing poverty through increased production of wood and other tree products for home consumption and sale 
•  Contributing to food security by restoring the soil fertility for food crops 
•  Cleaner water through reduced nutrient and soil runoff 
•  Countering global warming and the risk of hunger by increasing the number of drought-resistant trees and the subsequent production of fruits, nuts and edible oils 
•  Reducing deforestation and pressure on woodlands by providing farm-grown fuelwood 
•  Reducing or eliminating the need for toxic chemicals (insecticides, herbicides, etc.) Through more diverse farm outputs, improved human nutrition 
•  In situations where people have limited access to mainstream medicines, providing growing space for medicinal plants 

Agroforestry practices may also realize a number of other associated environmental goals, such as: Carbon sequestration

•  Odour, dust, and noise reduction 
•  Green space and visual aesthetics Enhancement or maintenance of wildlife habitat 
•  Adaptation to Climate Change There is some evidence that, especially in recent years, poor smallholder farmers are turning to agroforestry as a mean to adapt to the impacts of climate change. 

A study from the CGIAR research program on Climate Change, Agriculture and Food Security (CCAFS) found from a survey of over 700 households in East Africa that at least 50% of those households had begun planting trees on their farms in a change from their practices 10 years ago. The trees ameliorate the effects of climate change by helping to stabilize erosion, improving water and soil quality and providing yields of fruit, tea, coffee, oil, fodder and medicinal products in addition to their usual harvest. Agroforestry was one of the most widely adopted adaptation strategies in the study, along with the use of improved crop varieties and intercropping.

(Wiki)