Rangeland ecology Flashcards
What is a rangeland?
Includes: grasslands, shrublands, woodlands, wetlands, desert (savanna), steppe, tundra
That are grazed by domestic livestock or wild animals
Not including forests lacking grazable understory vegetation, barren desert, farmland, land covered by solid rock, concrete, and/or glaciers
What are some components of rangelands?
Herbaceous vegetation
Woody vegetation
Soil
Water
Livestock
Wildlife
Pastoralists
Agro-pastoralists
Microbes, insects…
What are some trends in rangelands?
- Overgrazing, trampling: soil erosion
- Increase in woody vegetation, reduction in herb vegetation
- Invasive species increase
- Less water available, climatic shocks
- Increase in wildlife-livestock conflicts
- More agriculture and privatization efforts
- Political will for settlement
What are some challenges rangeland face?
- Climate change
- Increasing human and livestock populations
- Increasing woody plant encroachment and invasive plant species
Why are pastoralists vulnerable to climate change?
- High livestock populations and strong dependence on grazing resources
=> if shock, and decrease grazing resources=> affects them ++
What are some characteristics of rangeland sharing between buffalo vs cattle ?
- Strong dietary overlap
- But cattle=> have broader niche, so competitive advantage
- Cattle density increases, while buffalo density decreases
=> buffalo density declines with cattle grazing intensity
What are some conclusions about overlap and disturbance in rangelands?
- Increasing livestock numbers and agriculture will lead to increasing conflicts
- Overlaps and conflicts can be spatially and temporally predicted
- Need for designated resting areas for wildlife and plant resources
- Joint land use planning is important, grazing grounds
Why are trees important in rangelands? What benefits do they provide to wild and domestic herbivores?
- Increase in nutrients sub-canopy (size of trees matters)
- Strongly improves microclimate
-Higher grass biomass and water content
=> however, the right density is important.
Give an example of invasive species in rangelands in Africa
Prosopis spp.
- Prosopis juliflora=> one of the work’s “worst alien invasives”
- Native to Latin America, was intentionally introduced in Africa against desertification in marginal lands
- Particularly a pest species in India and eastern Africa (Ethiopia, Sudan, Kenya, Tanzania)
Give an example of invasive species in rangelands in Africa
Prosopis spp.
- Prosopis juliflora=> one of the work’s “worst alien invasives”
- Native to Latin America, was intentionally introduced in Africa against desertification in marginal lands
- Particularly a pest species in India and eastern Africa (Ethiopia, Sudan, Kenya, Tanzania)
What is passive restoration?
It’s based on exclosure, allowing animals to graze periodically or not at all.
Can be seasonal or long-term, private or communal
Is traditionally accepted by communities
Includes rotational grazing
What are some points about passive restoration effectiveness?
- Moderate grazing in enclosures is recommended
- Traditionally respected by communities (long-term sustainability)
- Can act as grass bank during drought shocks
- Cut and carry potentially better than grazing (preventing trampling/compaction, erosion, uprooting by livestock)
- Presence of woody vegetation also important (management of enclosures, self-thinning)
- Less mobility, more privatization, more livestock
What are some points about passive restoration effectiveness?
- Moderate grazing in exclosures is recommended
- Traditionally respected by communities (long-term sustainability)
- Can act as grass bank during drought shocks
- Cut and carry potentially better than grazing (preventing trampling/compaction, erosion, uprooting by livestock)
- Presence of woody vegetation also important (management of enclosures, self-thinning)
- Less mobility, more privatization, more livestock
What does active restoration of rangeland includes?
Reseeding/pasture improvement
- Using fodder grasses
- Using legumes for soil improvement
- Seedballs
Livestock species diversification
- Better adapted breeds
- More browsing livestock
- Reduction in general
Holistic grazing
- Using livestock to improve rangeland quality
- Heavy rotational grazing as a possibility to stimulate grass growth (trampling)
What are some points about active restoration effectiveness?
- Few experiments on large-scale restoration efforts
- Often need to be observed over long duration (several seasons)
- Might become increasingly necessary if we want to suppress woody vegetation/invasives in the future
