Unit 4: From Shangombo to South Tavy Head Flashcards
aridity index of drylands
0.65 or less
how do people rely on dryland ecosystems
rain-fed or irrigated farming
extensive pastoralism
reason for Dartmoor mires project
to increase the ability of the planet’s biosphere to absorb more carbon than the atmosphere
10 mega tonnes stored in peat soils
mulching
thick layer of material placed over the soil and around plants, used to suppress weeds and lock moisture into the soil
impacts of desertifsction
- hunger
- overpopulation
- decrease in crop yield
- reduced farming
- loss of biodiversity
blanket bog
area of peatland, forming where there is a climate of high rainfall and a low level of evapotranspiration
peat
brown deposit resembling soil, formed by the partial decomposition of organic matter in the wet acidic conditions of bogs and fens
Light desertification
very slight damage occurs in vegetation cover and soil. not affect the biological capacity of the environment can be neglected
Moderate desertification
medium degree of damage of vegetation cover occurs and formation of small sand dunes and salinization of the soil which reduces production by 10- 25%
Severe desertification
spreading of weeds and unwanted shrubs in the pasture at the expense of desirable and wanted species occurs
increasing of the erosion activity which affects the vegetation cover and reduces production up to 50%
Very severe desertification
composition of active naked great sand dunes occurs and formation of many grooves and valleys and the salinization of the soil
Contour trenching
digging of deep trenches in the soil. The trenches are made parallel to the height lines of the landscape, preventing the water from flowing within the trenches and causing erosion.
Dartmoor Mires Project
five-year project to carry out restoration on areas of internationally important blanket bog, which are threatened by erosion
