密度无关和密度依赖性限制因素之间的差异

Thekey differencebetween density independent and density dependent limiting factors is thatdensity independent limiting factors areabiotic factorsand environmental factors such as weather, natural disasters, and pollution, etc. while density dependent limiting factors arebiotic factors例如捕食，寄生虫引起的竞争和疾病。

With the presence of unlimited resources, we expect a population to grow exponentially. However, achieving an indefinite exponential growth of a population is not possible in natural生态系统。人口达到极限并在某个点稳定，因为人口的密度受到各种因素的影响，包括密度依赖性和密度不足因素。密度无关的限制因素是影响人口规模和增长的因素，而不论人口密度如何。相比之下，密度依赖性限制因素是影响种群规模和增长的生物学因素，具体取决于人口的密度。

内容

1.Overview and Key Difference
2.What are Density Independent Limiting Factors
3.什么是密度依赖性限制因素
4.Similarities Between Density Independent and Density Dependent Limiting Factors
5.Side by Side Comparison – Density Independent vs Density Dependent Limiting Factors in Tabular Form
6。概括

What are Density Independent Limiting Factors?

Density independent limiting factors are the abiotic factors and environmental factors that regulate the population growth rate. Generally, they are physical or chemical in nature. These factors affect the birth and death rates of a population. Some of these factors include climate extremes, natural disasters (fires, floods, earthquakes and hurricanes) and pollution. Food or nutrient limitation is another density independent limiting factor.

Regardless of the population size, individuals may die due to these density independent limiting factors – environmental factors or abiotic factors. Therefore, a large population of a species can be regulated into a normal population by density independent manner by these factors.

什么是密度依赖性限制因素?

Density dependent limiting factors are biological in nature. The main factors are diseases, competition, and predation. These factors positively or negatively correlate with the population size. Density dependent limiting factors influence the population growth either by affecting reproduction or survival.

此外，这些因素会影响人口死亡率和移民。承载能力取决于密度依赖性限制因素。根据密度依赖性限制因素，可以生活在一个区域中的最大人数。

What are the Similarities Between Density Independent and Density Dependent Limiting Factors?

• 密度无关和密度依赖性限制因素都会影响人群的大小。
• They control the population growth.

What is the Difference Between Density Independent and Density Dependent Limiting Factors?

Density independent limiting factors are often abiotic factors, while density dependant limiting factors are often biotic factors. So, this is the key difference between density independent and density dependent limiting factors. That is; density independent limiting factors include nutrient limitations, natural disasters, severe weather, and pollution. Density dependent limiting factors include competition, predation, diseases and parasites and waste accumulation.

Below infographic summarizes the difference between density independent and density dependent limiting factors.

概括– Density Independent vs Density Dependent Limiting Factors

Size and the growth of populations are affected by many factors. These factors are mainly two types as density independent limiting factors and density dependent limiting factors. Density dependant factors are often biotic factors, while density-independent factors are often abiotic factors. Density independent factors include climatic extremes, natural disasters, foods, and pollutants. Density dependent limiting factors include disease caused by parasites, competition and predation.

Reference:

1. “Population Limiting Factors | Learn Science At Scitable”. Nature.Com, 2020,Available here。
2. “Population Regulation & Density Dependent Factors | Ecology “. Khan Academy, 2020,Available here。

Image Courtesy:

1. “Fire-Forest” By Cameron Strandberg from Rocky Mountain House, Alberta, Canada – DSC_7139（CC由2.0）viaCommons Wikimedia
2.阿拉斯加合作社鱼类和野生动植物研究部门马克·威普弗利（Mark Wipfli）的“阿拉斯加河流中的熊捕食可能很高”。公共区域。- 美国地质调查局（公共领域）通过Commons Wikimedia