1.1. The Self-Thinning Rule. Self-thinning, depicted in Figure 1A, describes a natural process in a single stand whereby the number of plants per unit area (p) decreases as average plant (or mean individual) above-ground weight (w) increases as time t progresses.

What is the self-thinning curve?

A self-thinning curve describes the relationship between density and biomass in a population that is limited by a resource. As density declines (due to mortality), the bio- mass of each individual tends to increase.

What is Yoda's law?

Yoda's power law A numerical description of the process of self-thinning among plant seedlings. Beyond a certain density of sowing, the number of surviving plants is not related to the initial seed density; instead, a constant relationship is evident between the density of survivors and their total biomass.

What is the law of constant final yield?

Abstract. The Law of Final Constant Yield states that when density is sufficiently high and resources become limited, the effects of competition will result in a constant biomass due to a proportional decrease in the size of the individuals.

What is interference in ecology?

Definition. (ecology) A form of competition wherein organisms directly vie for resources, such as by aggression. Supplement. In biology, competition refers to the rivalry between or among living things for territory, resources, goods, mates, etc.

Advanced GCM: Self-thinning Part1

23 related questions found

What is exploitative competition?

Exploitation competition occurs when individuals interact indirectly as they compete for common resources, like territory, prey or food. Simply put, the use of the resource by one individual will decrease the amount available for other individuals.

Why does self-thinning occur?

(A) Self-thinning is initiated after crowding occurs, resulting in decreasing plant density p(t) with time t. (B) A high initial planting density p₀ is compensated for by poor growth conditions for each individual resulting in a small individual biomass w at harvest after an initial growth time period (B-3).

What is self-thinning in forest?

The self-thinning rule describes plant mortality because of competition in crowded even-aged stands. ... The result is a “hierarchy of dominance and suppression” in which the smaller plants are at an accumulating disadvantage and finally die.

What happens to population numbers as intraspecific competition increases?

Consequences of intraspecific competition

The major impact of intraspecific competition is reduced population growth rates as population density increases. When resources are infinite, intraspecific competition does not occur and populations can grow exponentially.

What is it called when one group of species is replaced with others over time?

Ecological succession is the process of change in the species structure of an ecological community over time. The time scale can be decades (for example, after a wildfire), or even millions of years after a mass extinction. ... Succession was among the first theories advanced in ecology.

What is the largest population size that can be supported in an area without harming the environment?

The carrying capacity (K) is the largest population size that can be supported in an area without harming the environment.

What is a zero growth Isocline?

The zero-growth isocline describes expected equilibrium population sizes of one species if abundance of the second species is held constant, and vice versa.

What is thinning a plant?

When you plant vegetables from seed, you often have to plant more seeds then you will actually grow to maturity because not all seeds will germinate. However, after the seeds begin to grow, you need to 'thin' them out. So what does 'thinning' seedlings mean? “Thinning' is the practice of removing excess seedlings.

What is thinning in agriculture?

In agriculture and gardening, thinning is the selective removal of flowers, fruits, shoots, and seedlings or young plants to allow adequate space for the remaining organs/plants to grow efficiently. ... Also thinning is used in post harvesting.

What is the purpose of thinning?

The purpose of thinning is to increase economic gain. The gain may be achieved by offsetting the expense of carrying establishment costs to rotation age, increasing the value of the product, and/or increasing stand utilization.

What are the 5 types of species interactions?

The five major types of species interactions are:

• Competition.
• Predation.
• Parasitism.
• Mutualism.
• Commensalism.

What are some examples of exploitation?

Types of exploitation

• Sexual exploitation. This is when someone is deceived, coerced or forced to take part in sexual activity. ...
• Labour exploitation. ...
• Domestic servitude. ...
• Forced marriage. ...
• Forced criminality. ...
• Child soldiers. ...
• Organ harvesting.

What are some examples of exploitation competition?

An example is the competition for light between tall trees and smaller plants in the same ecological area in the forest. Synonym: exploitative competition.

Why do we thin plants?

The practice of thinning plants is done to allow them plenty of growing room so that they can receive all the proper growth requirements (moisture, nutrients, light, etc.) without having to compete with other seedlings. When you thin seedlings, you're also helping to improve the air circulation around them.

What are the types of thinning?

2) Ordinary Thinning: This is called as "Low Thinning". In ordinary thinning, the trees are removed from lower crown classes.
...
Following Methods of Thinning can be Adopted:

• Mechanical Thinning,
• Ordinary Thinning,
• Crown Thinning,
• Free Thinning,
• Crab's Advance Thinning,
• Numerical Thinning.

What is the importance of thinning in agriculture?

Importance of Thinnng-out

It gives enough space for the plants to grow. It allows crops to attain a better size when they mature.

What is Alpha in Lotka Volterra?

The Lotka-Volterra model incorporates interspecific competition by using a parameter called alpha. Alpha is the coefficient of competition (or competition coefficient) and measures the competitive effect of one species on another.

What happens when Earth reaches carrying capacity?

This earth too. When we will reach our carrying capacity (I hope we will not see anytime), water, food, shelter and resources will be very limited (per capita). People will be unhappy due to hunger (or maybe due to other reasons). ... The Earth will be fine but will have no trees and a lot of polluted water in the ocean.