Vertebrate Biology Lab Week 7&8: Digestion and Diversity of Mammals (ISU BIOL/A ECL 3650)

Mitscherlich's equation accounts for

less output per unit input at higher input levels

Massive soil structure is usually considered to be the least favorable type for plant growth because it

is the least permeable to air, water, and roots

What is a nonessential nutrient often found in plants that strengthens stems and reduces lodging

Si

Certain elements have specialized functions in plant growth but others, such as _____, seem to be involved in all of the vital processes of plants

potassium

A soil layer containing _____ fertilizers is likely to have more roots than a layer without the fertilizers

N and P

Which of these nutrient pairs is most likely to move through soil after application?

S and N

Which of the following elements are expected to be most abundant in plant tissue?

H, O, C

In which of these nutrient response equations do yields start to decrease as more and more fertilizeris applied

quadratic

What is "Hidden Hunger"

When plants are limited by nutrients, but do not show any visual deficiency symptoms

For corn production in Iowa, a study was conducted where N as a limiting nutrient was added in25 lb/acre units up to a total of 150 lb/acre. One would expect the greatest increase in yield per unitN at the ___ lb/acre rate.

25

The deficiency of a nutrient first shows on the older tissue (bottom of the plant), which indicates thenutrient

is likely mobile within the plant

A large difference in growth between plants with and without mycorrhizae is most likely to occur

where plants are grown in soil with low fertility

What important historical event lead to increased awareness of both soil tilth and health

The Dust Bowl

Root exudates

provide an energy source for soil microbes

The main source of this nutrient for all plants is the air

C

Which of these elements occurs in the highest proportion in sap compared with other nutrients

K

Soil structure is

the arrangement of sand, silt, and clay particles

What is the ideal % of pore space you want in your soil

60%

Soil crusts form when an unprotected soil with weak soil structure is subjected to

pounding by raindrops

Why do agronomists randomize plots out in a field

to account for soil variability

Which of these is likely the least satisfactory technique for determining the nutrient sufficiency status of a soil

Visual deficiency symptoms of growing plants

What is does the term "Myccorhizae" translate to

Greek for "fungus root"

Adding high rates of N fertilizer to growing tomatoes will

produce large amounts of vegetation but little fruit

Baule units allow us to quantify

nutrient interactions

Earthworms proliferate best when

manure is added to soil

Describe what an interaction is

where one factor affects the response to another

What is correlation in regards to a soil test

The relationship by the way the soil chemical test and the plants' ability to extract it (growth or yield)

What is calibration in regards to a soil test

at a given soil test level, where we determine the fertilizer needed for a given crop

Why are correlation and calibration needed to make proper nutrient recommendations

Important to prevent hidden hunger, increase yield, and prevent over-application of nutrients.

Identify the graph corresponding to a non-limited nutrient and high yield

Identify the graph corresponding to a non-limited nutrient but limited by something else

Identify the graph corresponding to a limited nutrient

Identify the graph corresponding to a nutrient toxixcity

What are three mobile nutrients

N, P, K

What are three immobile nutrients

Ca, Fe, Zn

Why might massive soil structure be a challenge in crop production

Massive soils are dense and restrict root growth and water infiltration

Define soil fertility

aspect of soil science concerned with the environment and source/availability of nutrients for plant growth with respect both to quantity and quality of the plant produced

Define Soil organic matter

the fraction of soil that is made up of anything that was once alive and is now in various stages of decompostion

Define soil sustainability

management of soil to ensure long-term productivity

List three soil plant interactions

nutrient uptake, microbial relationships, soil modification (relasing exuadates)

How can quality and quantity be affected as nutriet conctration is increased

quanitity keeps increasing while quality starts to decrease

Define growth

an irreversible increase in the size and mass of a plant

What are the limitations to growth that are affected by the crop

variety, planting date, and crop rotation

What are the limitations to growth that are affected by the soil

organic matter, CEC, and pH

What are the limitations to growth that are affected by the climate

Precipitation, air temperature, and light (quantity and availability)

What factors must be present for plant growth

H2O, air, light, and nutrients

What factors can be absent or restricted for plant growth

insects, disease, weeds, toxicity

What plant growth factors are limited to a suitable range

pH, temperature, or day length

What is the law of minimum

Plant growth is proportional to the amount of the most limiting nutrient

What is the law of diminishing returns

After a certain point, adding more fertilizer gives smaller and smaller yield increases.

What is Bray's nutrient mobility concept

Plants' response to a nutrient should be strongly influenced by how easliy the nutrient moves with water in soil

What are two mobile nutrients

N and S

What are four immobile nutrients

P, K, Ca, and Mg

Nutrient-Nutrient interactions (Macro or Micro)

interactions between different nutrients, one nutrient may enhance or limit the uptake of another

Nutrient-Crop Management interaction

How crop decisions affect nutrient needs. Ex. population, variety, or planting date

Nutrient-Soil Management interaction

How soil practices affect nutrient availability. Ex. tillage or residue removal.

Nutrient-Water interactions

How water impacts nutrient availability (Usually too much or too little)

What are the three types of tree roots

tap root, heart root, flat root

What are the 2-3 types of crop roots

Fiborous roots, taproots (primary), and taproots (storage)

Provide three functions of roots

Absorb water and nutrients, anchor, food storage

Label the roots in order from blue, maroon, green, and yellow

Brace, Crown, lateral, and Seminal

What is the root cap

Frontline of growth, protects the growing tip of plants and meristematic region, and secretes mucigel

What is the merestimatic zone

responsible for making new cells; it is the area of cell division and growth

What is the zone of elongation

increases in size through the absorption of food and water. As these cells grow, they push their root through the soil

What is the zone of maturation

where cells become specific tissues, such as epidermis, cortex, or vascular tissue

What is the root hair density of corn

146

What is the rhizosphere

The soil zone surrounding a plant root, where the biology and chemistry of the soil are influenced by the root

What are the physical factors affecting rooting depth and distribution

Soil compaction and tempature

What are the chemical factors affecting rooting depth and distribution

pH, nutrients (concentration and distribution), and H20

What are the Biological factors affecting rooting depth and distribution

Genetic potential, Competition with other plants, disease

What does a root microbe relationship look like

Plants releasing exudates to support benefical bacteria and soil microbes

What do Mycorrhizal assist with and what do they receive in return

Obtaining water, P, and micronutrients. The plant gives back carbohydrates

How do Ectomycorrhizae interact with plant roots

form a fungal sheath around roots and grow between root cells, found mainly in trees

How do Endomycorrhizae interact with plant roots

penetrate root cells to create arbuscules and vesicles, found in grasses and crops

What is soil composed of and percentages of each

45% mineral particles, 25% air, 25% water, and 5% SOM

What is SOM composed of

80% decomposed SOM, 10% organisms, and 10% roots

What are two forces of soil

Wetting and drying, root growth

What are two glues of soil

Clay and Oxides (Fe and Al)

Define soil texture

Relative content of the inorganic mineral particles of different sizes in soils

Define soil structure

The arrangement or organization of all soil particles (mineral and organic)

total soil porsity is between _________ - _________ of total volume

60-70%

What % of pores are large and what % are small

20%, 70%

How much pore space would you expect to find in a compacted layer

30-40%

What are the three things that destroy soil structure

Rain drops pounding, Compaction, conventional tillage

What are the four ways to improve soil structure

Increase OM, Minimize equipment traffic, crop rotation, and minimum/no till

What are the trade-offs when switching to minimum till

Weeds must be chemically controlled, compaction can increase, lower yields in no-till rain-fed areas

What are the three criteria for an element to be essential in a plant

Plant can't complete its life cycle without it, deficiency can only be solved by supplying the element in question, and the element is directly incolved in the metabolism of the plant

What nutrients are critical in structural parts of the plant

C, H, O, N,

What nutrient is found in highest concentration in the sap of plants

K

What nutrient is important in stems and leaves

Ca

What nutrient is important in grain and seed

P

What nutrients are important in creating enzymes

micronutrients

What is hidden hunger

When the plant is nutrient-deficient but not showing any symptoms. Usually, on a graph in between Deficient and maximum yield

What are problems with visual diagnosis of nutrient deficiencies

Maybe more than one nutrient deficiency, and hard to distinguish between other issues like disease

What are 4 deficiency symptoms

Chlorosis, Necrosis (leaf tips die back), reddening, or stunting

What are the four ways to diagnose plant fertility needs

Visual, greenhouse/field tests, Plan analyses, and soil chemical tests

What are the four components of soil testing

Collect a representative sample from a field, determine the quantity of plant available nutrients, interpret soil test results (soil test calibration), and Estimate the application amount

When should soil samples not be collected

Wet, frozen soils, or growing crop

What should you avoid when setting out to soil sample

Areas where things other than nutrients are affecting growth

What are the three types of soil sampling

Simple randon, zone sampling, grid sampling