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31

No, I don't think auto-regulation explain much in the population sizes of predators. Group selection may explain such auto-regulation but I don't think it is of any considerable importance for this discussion. The short answer is, as @shigeta said [predators] tend to starve to death as they are too many! To have a better understanding of what @shigeta ...


24

Short answer Cockroaches are an integral part of the food chain. Background Cockroaches are an important source of food for a number of organisms, such as arthropods, birds, and mammals. As such, they are an important part of the food chain. Cockroaches also play an important role in nutrient recycling. Most species of cockroach are detritus feeders and ...


15

They don't have to "contribute" as such. All they have to do is survive and pass on their genes to their offspring. Any benefits that they have (in terms of detritus cleaned up, etc.) or harms that they cause is purely coincidental. There's no "desire" on the behalf of species to make things "better". All they "do" is try to survive in their existing ...


14

Remi.b's answer is an excellent one, and this should be taken as a supplement to it: It's possible your simulation is correct The Lotka-Volterra equations are what is known as a deterministic model, and it describes the behavior of predator-prey systems (in a somewhat simplified fashion) in large populations. Small populations are subject to what is known ...


10

Disclaimer: the question is too broad and speculative to some extent, and thus less likely to get complete answer (at least in a single post). As is already known, thousands (or millions) of species are dependent on coral reefs for their survival and are likely to get extinct (unless they adapt) because of destruction of coral reefs. A short list includes ...


9

One of the possible adjustments of these mathematical models is to introduce a "place to hide", making some (small) percent of the prey population not accessible (or much more difficult to access) for predators. After the number of predators decreases from starvation, prey individuals are relatively safer outside the "place to hide" and can grow over this ...


9

Feral camels have environmental, economic and cultural impacts in Australia's Northern Territory (Dept of Land Resource Management, Australia). In central Australia, camels feed on more than 80% of the available plant species. Feral camels severely defoliate and suppress the recruitment of some shrub and tree species, with such impacts being greatly ...


7

This question is really asking for examples, and the list of ways that knowledge of physics can be used in biology could be very long. However, here are a couple of examples: Systems ecology, especially with regard to energy and nutrient flow. This type of ecology can be strongly influenced by physics. For one example see the book Theoretical Ecosystem ...


7

This question is too broad. What type of temperate forest? The European Environment Agency recognized dozens of temperate forest types: Acidophilous oak and oak‑birch forest types Mesophytic deciduous forest types Beech forest types Mountainous beech forest types Broadleaved evergreen forest types Floodplain forest types Non‑riverine alder, birch or aspen ...


6

The problem lies in soil bacteria. There has been a project on a larger scale: Biosphere 2. After their initial trial they realised $O_2$ levels are getting much lower from what was predicted. The scientists team investigated the problem deeper and came to the conclusion that there was a lot of dead organic matter in the soil, which got consumed by aerobic ...


5

You need to add Bell curves to your simulation. The most important curve to simulate is the nutritional quality of the prey though there are plenty more thing to curve like speed and virility for prey and predators both. Nature uses lots of Bell curves so they must be good for something, such as softening the harsh effects of pure exponential growth. I ...


5

The cost would increase; either because pollination services are not provided and the supply is decreased; or because the cost to producers goes up as they must pay for artificial pollination. See the extremely detailed analysis in Winfree et al. edit I imagine what you're actually asking for is a $ figure "per apple". This depends on the location, crop, ...


5

The traditional explanation for this is that nitrogen compounds are more mobile than phosphorus compounds. As a result, nitrogen is more likely to flow through terrestrial ecosystems and accumulate in freshwater ecosystems, making P relatively more limiting than N in freshwater. Phosphorus compounds (e.g., phosphate) are more "sticky" and tend to bind/sorb ...


4

The percentage of biomass at each stage will vary tremendously, based on the following factors: 1: Relative turnover rate of the biomass. When biomass turnover is very high (for example in plankton and whales), it is possible for whale biomass to exceed that of the plankton, even through the whales feed on plankton. Therefore, it is better to use a pyramid ...


4

The problem is not really that we don't understand some stuff (lthough this is certainly true) but that an ecosystem, or the biosphere is a highly complex network of interactions. This network is continuously displaying some chaotic (determinist but not foreseeable) behavior. In such a system it becomes very hard or practically impossible to predict what the ...


4

This question is indeed off topic here but the reason these planets don't have moons is pure chance. Different moons have different origins, some could be meteorites or other drifting bodies that were captured by the planet's gravity, others could be pieces of the planet itself that were spun off before it solidified or from an impact event. Others could be ...


4

Wood ash is commonly used as a fertilizer. It acts this way in natural burning ecosystems also, where the ash from burned plants fertilizes the growth of new plants and those that survive the wildfires. The primary constituents of wood ash are calcium and potassium salts. Lye is extracted from these salts by extracting them in water; the hydroxide salts are ...


3

Remi.b's answer is spot on - predicting the effects of losing a given species is nigh on impossible. However, I do think that there are some general trends that can give us some intuition, and make the campaign to protect certain species more than just an ethical issue. Biodiversity (i.e. having a wide range of different organisms (and genetically diverse ...


3

After a quick glance at the book "Light and Photosynthesis in Aquatic Ecosystems" by Kirk (2010), I think that the cause for the productivity dip towards the surface partially lies in photoinhibition, due to high light intensities at the surface. Here are a couple of relevant quotes from the book (Google books: p. 371): In this light saturated state, the ...


3

Table 1 on the next page (p. 36) lists a number of properties for each of the three "growth forms". For information, properties include: Life history types Diversity (taxonomic & ecological) Body size Stability I have to admit that some of these properties doesn't really make sense to me under these headings (at least from the common use of these ...


2

Pianka's index of niche overlap is defined in his papers from 1973 and 1974, as: $O_{kl}=\dfrac{\sum_i^n{p_{il} p_{ik}}}{\sqrt{\sum_i^n{p_{il}^2} \sum_i^n{p_{ik}^2}}}$ where $O_{kl}$ is the resource overlap between species $k$ and $l$, and since the index is symmetric $O_{kj} = O_{lk}$. $p_{ib}$ represents the proportion of resource $i$ that is used by ...


2

This boils down to one main reason: competition. Animals, in general, don’t like sharing resources with direct competitors, but this violence over food, territory, and in the case of intraspecific relations, breeding rights seems to be more extreme the higher up you go on the food chain. An excellent example of this regards cougars. A dominant tom cat in ...


2

What are the branches of system ecology that scientists research in nowadays? Or what can system ecology can applied to, or be used? This field is often referred to as systems ecology or ecosystem ecology. It is the study of ecosystems. Thermodynamic principles are often used to construct food/system webs (networks) to understand cause and effect within the ...


2

I am not sure I fully understand where is your misunderstanding. I think your whole misunderstanding boils down to the representation of food chain. Actually, let's talk about food web as the name gives an intuition of what is happening that is more correct than the term food chain. The conceptual view of the food web in a pyramid is super misleading. This ...


2

You must read this article: “Most cockroaches feed on decaying organic matter, which traps a lot of nitrogen,” Kambhampati said. “Cockroach feeding has the effect of releasing that nitrogen (in their feces) which then gets into the soil and is used by plants. In other words, extinction of cockroaches would have a big impact on forest health and ...


2

And how to estimate the amount approximately? You cannot. Most of the earth is water, and fauna diversity is highest in water. We are still tagging and tracking the movement and reproduction cycles of animals, and that is a never ending task. I say we cannot reach an accurate approximation because of how these projects work. They are targeted towards the ...


2

I disagree with GForce's explanation; the meaning is not that growth of prey populations causes instability in predator species. The sentence is merely saying that without predation, prey population growth is more likely to be at a level which leads to ecosystem instability. The term "but for predation" means "if it wasn't for the effects of predation". In ...


2

There are some well established methods for this. For example, estimating forest C stocks and fluxes is done for national C accounts which are used by the Intergovernmental Panel on Climate Change (IPCC) for global reporting. The usual method is to measure the diameter of all trees in a defined area (a plot, e.g. like you suggest of 100 square meters), then ...


2

This question is very broad and this would require a lot of calculations, I will focus on the carbon dioxide in the trees, hopefully some other users can add details in respect to the organism and their carbon dioxide storage. I found an article(R.Jandl et al.,(2007)) which did some calculations, this site does a really good job in explaning these ...


2

All green plants do Photosynthesis as well as Respiration. Plants respire during the day and night, but they only photosynthesis during the day when it is light: there is equations for aerobic respiration and photosynthesis: C6H12O6 + 6O2 → 6CO2 + 6H2O (aerobic respiration) 6CO2 + 6H2O → C6H12O6 + 6O2 (photosynthesis) In terms of reactants and products, ...


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