3.8 KiB
| title | chunk | source | category | tags | date_saved | instance |
|---|---|---|---|---|---|---|
| Carrying capacity | 4/5 | https://en.wikipedia.org/wiki/Carrying_capacity | reference | science, encyclopedia | 2026-05-05T07:17:32.393840+00:00 | kb-cron |
Another issue to consider when applying carrying capacity, especially to humans, is that measuring food resources is arbitrary. This is due to choosing what to consider (e.g., whether or not to include plants that are not available every year), how to classify what is considered (e.g., classifying edible plants that are not usually eaten as food resources or not), and determining if caloric values or nutritional values are privileged. Additional layers to this for humans are their cultural differences in culinary preferences (e.g., some consume flying termites) and individual choices on what to invest their labor into (e.g., fishing vs. farming), both of which vary over time. This leads to the need to determine whether or not to include all food resources or only those the population considered will actually consume. Measuring water resources carrying capacity is likewise highly arbitrary: choices in temporal resolution (e.g., monthly versus annual), spatial resolution (e.g., how subbasins are delineated), and whether to include human activities such as inter-basin water transfers and reservoir storage in the assessment can all lead to vastly different WRCC results. Carrying capacity measurements over large areas also assumes homogeneity in the resources available but this does not account for how resources and access to them can greatly vary within regions and populations. They also assume that the populations in the region only rely on that region's resources even though humans exchange resources with others from other regions and there are few, if any, isolated populations. Variations in standards of living which directly impact resource consumption are also not taken into account. These issues show that while there are limits to resources, a more complex model of how humans interact with their ecosystem needs to be used to understand them.
== Recent warnings that humanity may have exceeded Earth's carrying capacity == Between 1900 and 2020, Earth's human population increased from 1.6 billion to 7.8 billion (a 390% increase). These successes greatly increased human resource demands, generating significant environmental degradation.
=== Millennium ecosystem assessment === The Millennium Ecosystem Assessment (MEA) of 2005 was a massive, collaborative effort to assess the state of Earth's ecosystems, involving more than 1,300 experts worldwide. Their first two of four main findings were the following. The first finding is:Over the past 50 years, humans have changed ecosystems more rapidly and extensively than in any comparable period of time in human history, largely to meet rapidly growing demands for food, fresh water, timber, fiber, and fuel. This has resulted in a substantial and largely irreversible loss in the diversity of life on Earth.The second of the four main findings is:The changes that have been made to ecosystems have contributed to substantial net gains in human well-being and economic development, but these gains have been achieved at growing costs in the form of the degradation of many ecosystem services, increased risks of nonlinear changes, and the exacerbation of poverty for some groups of people. These problems, unless addressed, will substantially diminish the benefits that future generations obtain from ecosystems.According to the MEA, these unprecedented environmental changes threaten to reduce the Earth's long-term human carrying capacity. "The degradation of ecosystem services could grow significantly worse during the first half of this [21st] century," they write, serving as a barrier to improving the lives of poor people around the world.