features of fertile soil

Question 1

list the features of fertile soil

Answer 1

1) water content
2) soluble materials
3) air content
4) dead organic matter
5) PH
6) soil biota
7) soil texture
8) soil structure
9) soil depth

Question 2

outline the importance of water content in soil

Answer 2

• essential for all organisms
• good drainage to avoid waterlogging an anaerobic conditions
• retains enough water for the survival of soil biota
• plant nutrients dissolve in water in ionic form allowing plant survival

Question 3

outline the importance of soluble materials in soil

Answer 3

• macro nutrients such as nitrogen, phosphorus and potassium
• micro nutrients such as boron, cobalt, iron and magnesium
• need to be soluble so they can be absorbed by the plant in ionic form allowing survival

Question 4

outline the importance of air content in soil

Answer 4

most living organisms that increase soil fertility are aerobic so well aerated soils are likely to be more fertile

Question 5

outline the importance of dead organic matter in soil

Answer 5

• releases plant nutrients as it decomposes
• increases water retention of the soil
• provides food for soil biota

Question 6

outline the importance of PH in soil

Answer 6

• most soils range from 5.5-7 which is the range of tolerance for most soil biota
• acidic soils increase leaching of plant nutrients and damage root cell membranes
• alkaline conditions phosphates become insoluble

Question 7

outline the importance of soil biota in soil

Answer 7

• detrivores break up dead organic matter and release nutrients into the soil
• organisms such as earth worms help with aeration by creating tunnels
• decomposers break down dead organic matter
• nitrogen fixing bacteria convert gaseous nitrogen into ammonium ions
• fungi create symbiotic relationships with plant roots aiding phosphate uptake

Question 8

outline the importance of soil texture in soil

Answer 8

refers to the different sizes categories of mineral particles in the soil which effect drainage, water retention, root penetration and aeration

Question 9

outline the importance of soil structure in soil

Answer 9

soil particles form aggregates called peds
the ped type affects soil properties and fertility

1) crumb peds are small and round allowing good drainage, aeration and easy root penetration
2) platy peds are large and flat which reduce drainage ,aeration and root penetrations

Question 10

what is the difference between soil texture and structure

Answer 10

texture refers to the proportions of different size categories such as sand, silt, and clay

structure refers to the grouping of soil particles into porous compounds

Question 11

list the types of soil texture from the largest to smallest sizes

Answer 11

1) sand
2) silt
3) clay

Question 12

outline the importance of soil depth in soil fertility

Answer 12

deeper soils are less likely to become waterlogged or to dry out rapidly
deeper soils aid good root anchorage