Module 5-livestock production and soil quality

Question 1

do livestock negatively or positively impact soil

Answer 1

they can impact soil both positively and negatively

Question 2

what is soil organic matter

Answer 2

Soil organic matter is made up of plant, animal and microbial residues at various stages of decomposition

Question 3

what does soil organic matter do for the soil

Answer 3

It is a small but critical soil component as it releases nitrogen for plant growth, enhances soil structure and improves nutrient and moisture retention and release

Question 4

what does SOM do to carbon

Answer 4

The soil organic matter also immobilizes carbon that would otherwise be returned to the atmosphere as CO2

Question 5

how can SOM levels be maintained or improved

Answer 5

Organic matter levels can be maintained or improved by using longer crop rotations, reducing tillage, plowing legume crops into the soil, seeding perennial forages, and adding livestock manure. perennial crops can also increase SOM

Question 6

what happens to N and C on ungrazed rangeland and what do animals do to change it

Answer 6

C and N content of ungrazed rangeland may remain tied up in dead plant material that accumulates above the ground where it can blow away without contributing to the soil, livestock grazing that soil trample the plant material into smaller pieces aiding in decomposition and incorporation into the soil

Question 7

how is manure beneficial for plants

Answer 7

The manure excreted by livestock is also rich in plant nutrients that are returned to the soil as the manure decomposes

Question 8

what does sustainable rangeland management require

Answer 8

it requires retention or increase of soil organic matter and soil carbon stocks; while livestock grazing can increase soil organic matter, it can also deplete soil organic matter when management is not synchronized with the condition of the forage and the soil.

Question 9

what are the benefits of vegetation covering pasture when it comes to water

Answer 9

Vegetation cover provided by pasture and rangeland to feed livestock enhances water movement into the soil by protecting the surface from potentially damaging effects of rain and by enhancing the water permeability of the soil surface

Question 10

how do the root systems of perennials benefit more than just the plant

Answer 10

Root systems of perennial forages infiltrate the soil and increase its water carrying capacity

Question 11

how is water retention capacity decreased

Answer 11

Water retention capacity of the soils is decreased when high stocking densities over a prolonged period of time compact the soil to an extent that renders it impermeable

Question 12

what happens when there’s increased water retention

Answer 12

Increased water retention in conjunction with continuous cover can stimulate the production of soil methanotrophs that oxidize methane and reduce GHG emissions.

Question 13

what are methanotrophs

Answer 13

Methanotrophs are prokaryotes that metabolize methane as their source of carbon and to unlock the energy of oxygen, nitrate, sulfate, or other oxidized species

Question 14

how do high stocking rates and overgrazing of pastures and rangelands affect soils

Answer 14

it’ll contribute to soil erosion, salinization, and pollution

Question 15

what is poaching

Answer 15

Heavy livestock such as cattle can compact soil structure and destroy vegetation in areas of a field they tread often or over an entire field if the stocking density is too high

Question 16

it is poaching so bad

Answer 16

it can destroy vegetation beyond its ability to recover and render the soil impervious to new growth

Question 17

when land is poached what happens when plants aren’t able to grow on a pasture

Answer 17

Removal of the vegetative cover and compaction of the soil decreases the ability of the land to drain making the soil particles susceptible to erosion

Question 18

how can eroded soils contribute to eutrophication

Answer 18

Eroded soil can transport organic matter and phosphorus to surface water sources

Question 19

how can soils contribute to releasing N2O

Answer 19

Anaerobic zones in waterlogged soil can also encourage denitrification and the release of N2O into the atmosphere

Question 20

how many percent of the pastures in the world has been damaged by livestock grazing

Answer 20

20 to 35 % of the world’s permanent pastures have been degraded by livestock grazing

Question 21

what benefits would we see if we improved grazing management

Answer 21

Improving grazing management around the world would increase land-use efficiency by increasing forage production and recovering degraded land

Question 22

what effects do we see with light grazing

Answer 22

an increase in ammonia and organic carbon

Question 23

what effects do we see with moderate grazing

Answer 23

increase in bulk density, penetration resistance, available phosphorous, compaction, and alkalinity. you’d also see a decrease in in organic carbon and total nitrogen

Question 24

what effects do we see with heavy grazing

Answer 24

we would see an increase in compaction, bulk density, penetration resistance. you’d see a decrease in organic carbon, water content, nitrate, microbial biomass carbon, and soil moisture

Question 25

how many percent of the worlds milk and meat come from grassland production

Answer 25

25 percent of the world's milk and beef comes from grassland production

Question 26

how does soil degradation threaten lively hoods

Answer 26

Soil degradation decreases the productivity of that land thereby threatening livelihoods; it also contributes to increasing GHG emissions

Question 27

how many livelihoods depend on grassland livestock production

Answer 27

billions of the worlds poorest people

Question 28

what factors make for different effects of livestock grazing on the land

Answer 28

The effects of grazing livestock on grasslands are a function of management that must be adapted to regional differences in soil type, climate, grazing species, and land-use restrictions.