NREM 120 EXAM 3 | Questions And Answers Latest {2024- 2025} A+ Graded | 100%
Verified
Grasslands - - Grasses with some forbs
- areas free of trees
- between 10-30" rainfall
- most productive grazing areas
- once roamed by wild animals
- now plowed for ag or used for livestock grazing
grassland driving forces - seasonal dormancy, herbivores, fire, management
Grassland Biome - an area in almost every continent; evolved with large herbivores
other rangelands include: - - tropical savannas
- tundra
- desert shrublands
- many temperate forests, esp. conifer forests
rangland totals - World: 50% ice free land
USA: 29% total land area
North American Prairie - made of tall grass, mixed grasses, and short grasses
why is there an east to west shift from forest to tall grass to short grass prairie? - influence of the Gulf of
Mexico causing a moisture gradient
metabolic reserve - what needs to be left behind to make grazing sustainable
,basal zone - lowermost portion of the leaf; as long as leaf is not eaten beyond basal zone, leaf will grow
to its original length
overgrazing - - the basal zone (MR) is grazed
- root reserves are not allowed to replenish between grazing events
- forage requires a period of rest
Grazing grass regrowth appears within ___ - 7 days
_____ weakens the _____ plant community - overgrazing; dormant
what happens when grasslands are overgrazed? - allows for increases in plant community deteriorating
and eventually invaders to move in
consequences of overgrazing - - reduced ground cover
> soil erosion
> wind erosion
> nutrient runoff
>gully formation
- deteriorating plant community
- desertification
Homestead Act of 1862 - 160 acres of virtually free land to American citizens or soon-to-be citizens
between west of the Mississippi
John Wesley Powell - - concerned about the 160 acre parcel size out west
- report on lands of the arid region 1878
- recommends grazing 2,500 acre parcels
, In what years was the western rangeland seriously degraded? - 1860-1930
Tallgrass parairie current status - - large animals usually lost
- small animals, like the Karner Blue butterflies, struggling due to habitat loss AND fragmentation
Grassland bird status - birds that nest in grass structures or on the gound
- drastic long-term population decliens
> decreasing plasture acres
> earlier alfalfa harvests
> removal of fencerows
> increased homogeneity of crop uses
Currents status of the short grass pairaie - - suffered badly from overgrazing, 1860-1940, and from
doughts
- situation slowly impoving on most areas
why does the short grass pairie recover so slowly? - lack of moisture
years after Powell's 1878 Report - - western rangeland seriously degraded
- Forest Service formed
- Taylor Grazing Control Act
- BLM authority
- Conservation Reserve Program
US Forest Service - created in 1905 by the Roosevelt administration to manage the forest lands set aside
as National Forest.
after the Powell Report:
- restrict cattle stocking rates
Verified
Grasslands - - Grasses with some forbs
- areas free of trees
- between 10-30" rainfall
- most productive grazing areas
- once roamed by wild animals
- now plowed for ag or used for livestock grazing
grassland driving forces - seasonal dormancy, herbivores, fire, management
Grassland Biome - an area in almost every continent; evolved with large herbivores
other rangelands include: - - tropical savannas
- tundra
- desert shrublands
- many temperate forests, esp. conifer forests
rangland totals - World: 50% ice free land
USA: 29% total land area
North American Prairie - made of tall grass, mixed grasses, and short grasses
why is there an east to west shift from forest to tall grass to short grass prairie? - influence of the Gulf of
Mexico causing a moisture gradient
metabolic reserve - what needs to be left behind to make grazing sustainable
,basal zone - lowermost portion of the leaf; as long as leaf is not eaten beyond basal zone, leaf will grow
to its original length
overgrazing - - the basal zone (MR) is grazed
- root reserves are not allowed to replenish between grazing events
- forage requires a period of rest
Grazing grass regrowth appears within ___ - 7 days
_____ weakens the _____ plant community - overgrazing; dormant
what happens when grasslands are overgrazed? - allows for increases in plant community deteriorating
and eventually invaders to move in
consequences of overgrazing - - reduced ground cover
> soil erosion
> wind erosion
> nutrient runoff
>gully formation
- deteriorating plant community
- desertification
Homestead Act of 1862 - 160 acres of virtually free land to American citizens or soon-to-be citizens
between west of the Mississippi
John Wesley Powell - - concerned about the 160 acre parcel size out west
- report on lands of the arid region 1878
- recommends grazing 2,500 acre parcels
, In what years was the western rangeland seriously degraded? - 1860-1930
Tallgrass parairie current status - - large animals usually lost
- small animals, like the Karner Blue butterflies, struggling due to habitat loss AND fragmentation
Grassland bird status - birds that nest in grass structures or on the gound
- drastic long-term population decliens
> decreasing plasture acres
> earlier alfalfa harvests
> removal of fencerows
> increased homogeneity of crop uses
Currents status of the short grass pairaie - - suffered badly from overgrazing, 1860-1940, and from
doughts
- situation slowly impoving on most areas
why does the short grass pairie recover so slowly? - lack of moisture
years after Powell's 1878 Report - - western rangeland seriously degraded
- Forest Service formed
- Taylor Grazing Control Act
- BLM authority
- Conservation Reserve Program
US Forest Service - created in 1905 by the Roosevelt administration to manage the forest lands set aside
as National Forest.
after the Powell Report:
- restrict cattle stocking rates
