soil resources (Fach) / drylands (Lektion)
In dieser Lektion befinden sich 14 Karteikarten
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Diese Lektion wurde von tinalinea92 erstellt.
- how is the PET of drylands defined? PET is smaller 0,65
- how long is lenght of growing period in dry savanna 90-180 days
- LGP of sahel 65-90 days
- LGP of deserts < 65 days
- distribution over land, how is the percentage? drylands cover 40% of worlds land
- dry lands are fragile environments ... why? land degradation water deficit extre temp and a higher production potential -> solar radiation
- dry land managment must be ... sustainable
- management of dry lands harvesting of water from rainfall by wholes and seperation of ground for plant irrigation
- what are the water harvesting system components? the rainfall -> amount and intensity, the length and duration, time of rainfall and texture of the spol in the landscape the water requirement -> type age and size of the plant, ddrogh tolerant species and natve plants water collection and distribution simple or complex
- example for water collection... Qanat -> channel system in Iran
- how to storage water? in small reservoirs -> using small pumps to get water for cultivaing vegetables
- building dams on seasonal and nonseasonal rivers in Irand and Egypt
- what are the benefis of water arvesting reducing potable/ trinkbar water usw and related costs reducing offsite flooding and watererosion water source for plants -> rainwater cleaned and free from salts reducing salt accumulation in the soils easy achieving by good planning and design
- what is the conclusion? high potential of dry lands if beeing well used reducing poverty if water use is managed well water harvesting improving soil fertility and increased water use efficiancy main water soource