ENVIRONMENTAL ASPECT OR SOCIO-ECONOMIC CONCERN

EXAMPLE OF THRESHOLD OF "MAJOR IMPACT"

Slopes

If the slope angles, local geology and soils, and rainfall patterns are such that more than 5 percent of a project area exceeding 1 km² is likely to become unstable.

Soils

Soil erosion likely to affect visibility and measurability more than 20 contiguous ha of land.

Loss of nutrients, organic matter, CEC or mycorrhizae, compaction, laterization, rutting or induced poor drainage that will prevent forest regeneration on more than 50 ha of land.

Sediment

Accelerated sedimentation likely to shorten the life span of reservoirs by years, to require dredging of navigable waterways, or to destroy spawning grounds or benthos that support subsistence or commercial fisheries.

Water Resources

Denudation of forested watershed likely to cause downstream flood losses that are measured in human lives and in monetary terms.

Induced turbidity, eutrophication or other alteration of water quality likely to eliminate one or more key species in the aquatic foodchain, or likely to require technical modification of waterworks, or likely to affect a subsistence or commercial fishery.

Down-basin decreases in flows, especially low flows, that interface with domestic or agricultural with drawls of water.

Climate and Air Quality

Ground temperatures and humidity levels so altered that seedlings of valuable tree species can no longer survive or germination can no longer take place.

Forest removal in a semi-arid region that is likely to cause the advance of the desert.

Removal of a forest that effectively screens one or more settlements from high winds or dust storms.

Vegetation

Likelihood that high forest will not regenerate itself on land set aside for forest growth.

Likelihood that entire species will become extinct. Clear-cutting more than 1 km² in a region known for its high diversity of plant species in a particular regional, national or sub-continental context.

Likelihood that seed trees of the prime timber species will not survive selective logging.

If more than 1 km² of adjacent uncut forest is likely to be affected by mechanical injury, windthrow, altered hydrologic conditions, illegal felling or intensified shifting cultivation.

Likelihood that persistent weeds will invade more than 100 ha and effectively prevent the regeneration of forest.

Wildlife and Fisheries

Elimination of rare, endangered or protected species of animals.

Elimination of more than one-third of the population of any one species (obviously, in the case of some endangered species, the elimination of even a few individuals could have serious genetic repercussions).

Destruction of key habitats (nesting sites, preferred feeding grounds, aerial pathway, etc.) of rare, endangered or protected species.

Displacement of animals in such numbers as to cause crop losses or detectable reproductive stress in the displaced and receiving populations of animals.

Creation of new access to endangered or other vulnerable species likely to be used by poachers.

Traditional Cultures Subsistence Economy

Any likelihood of violent conflict between forestry and workers and local residents.

Likelihood that the subsistence economy will be replaced by a cash economy (whether or not it is desirable).

Any now contact with forest dwellers not previously in contact with the dominant culture and economy.

Any destruction of traditional habitats and supplies of food, fuel and construction or handicraft materials that will create a dependence on the outside economy.

Damage to or destruction of burial grounds, trees, sites or other features of religious or other cultural value.

Employment arrangements that disrupt traditional folkways but make it impossible to return to these folkways once the forestry operations are over.

Any intensifications of shifting cultivation that is judged to be beyond the carrying capacity of a region.

Demographic-Economic Expansion

Need to invest in new schools, public buildings, hospitals, roads and recreational facilities.

Waste generation that requires investment in new disposal facilities.

Employment and other economic benefits to more than 5 percent of the local population.

Deferral or abandonment of mining, agricultural, tourist or other economic plans because of conflicts with forestry activities.

Likelihood that influx of newcomers will require the increased intervention of public-safety, public-health or welfare authorities.

Any new settlement, planned or spontaneous.

Epidemiology

Any increase in the rate of incidence of already present diseases or the introduction of new diseases that requires the intervention of public-health authorities.

Conservation

Any measurable damage to established conservation areas (national parks, protection forests, strict nature reserves, game reserves, species sanctuaries).

Forest removal or forest roads in areas identified for possible preservation or conservation status.

New road network and major interruption of habitat (eg., segmentation of gallery forest) in the buffer zone around a park or nature reserve.

Damage, including visual degradation, that precludes further use of a well recognized public recreational area, even if it lacks legal status as such.