The physical transformation of Central America’s vegetation

The following are extracts from an article by Eric Holt Gímenez, Director of the Institute for Food and Development Policy/Food First and a regular commentator on development policy in Central America. The article was originally published on the Oxfam Central America website ( soon after Hurricane Mitch in 1998.

Hurricane Mitch may be the most devastating ecological event to occur in the history of Central America. This is because human impact on the isthmus over the last century transformed the original, heavily forested landscape into a wide patchwork of open fields bordered by groves of trees. Pre-Colombian slash and burn rotational systems were converted from small cultivated plots with extensive areas of forested fallow to intensively farmed, non-rotational systems.

Agriculture reduced the ecological succession of the region from multi-storied, high and medium canopy cover to ecosystems made up of low-lying broadleaf plants, grasses and bare soil. The ecological effect of this transformation was an overwhelming shift in the primary store of nutrients from the biomass (trees) to the soil. This shift in the nutrient store and the corresponding disappearance of the rich litter layer was accompanied by a dramatic reduction in the levels of nutrients held in these ecosystems. … Modern farming has been possible only by the addition of fertilisers.

The change in agroecosystem structure and function from biomass to soil and from nutrient cycling to nutrient addition also removed the protective forest cover, exposing the soil and its reduced nutrient layer to intensive tropical rains. Hurricane Mitch may not have been the first hurricane to dump two metres of rain on the isthmus in less than a week, but it was the first time this large an area of Central American soil had been directly exposed to the intensity of that much rain – ever.

The result was devastating. But the terrible death toll and loss of homes due to mudslides and flooding (now followed by hunger and disease) are only preludes … Mitch was the disaster; the crises are yet to come.

The human effects of the process of deforestation

1. Campesinos with no legal title to their land are moved off the land they have farmed for many years, in some cases for generations, by wealthy landowners seeking to expand their holdings or by large companies (often foreign TNCs) seeking to take over fertile land for plantation agriculture or to take over land that is rich in minerals.

2. The company fells any timber that stands in the way of their operations.

3. The displaced campesinos and families either:

A) migrate into the cities

B) move onto more marginal land as yet not in demand for other purposes

C) stay put and become plantation labour and find what work they can in the vicinity when their plantation work lays them off


D) migrate to other areas where seasonal labour is required – some agricultural labourers become itinerant, moving from area to area.

(In all four of the above options, the household finds it harder to subsist and has to depend on the pluri-activity of all members of the household.)

4. Following Option B above – at the agricultural frontier, the campesino has no option but to deforest in order to clear land for planting. Being marginal land, often on slopes and with its nutrients in the litter rather than in the biomass (trees), this land will only support plantings for a couple of years before the litter and its nutrients are lost.

5. The campesino household moves on to another area and repeats the process. Cattle ranchers move in behind them and their cattle compact the ground and turn it into a sterile savannah-like area.

6. The cleared land becomes vulnerable to erosion and slope failure. Loss of trees and other vegetation reduces the watershed’s capacity to hold water. This causes flooding downstream during the rainy season and reduces the water that filters into the underground water table.

7. Other effects include: rivers and lakes filling with sediment and becoming shallower, leading to a greater likelihood of flooding during the rainy season; siltation of reservoirs behind HEP dams reducing the life and capacity of such plants on which Central American nations have a high dependence for their electricity; sedimentation of coastal estuaries damaging habitats for shrimp and other marine life; and loss of biodiversity.