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3

Lightning results in nitrogen fixation (Draphco et al., 1967; Hill et al., 1980). It is one of the main abiotic nitrogen fixation mechanisms. As you would know very well, nitrogen fixation is important for all organisms.


0

The most recent biomass estimates that I have come across have come from the Universit├Ąt Potsdam and University of Rhode Island School of Oceanography. They have reduced the previously accepted biomass estimate of around 1000 billion tons by 10-45%. So doing the math, that would suggest the current estimates are between 550 and 900 billion tons of biomass ...


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 ...


0

It's essentially saying that high densities of prey species can cause ecosystem instability not only for themselves but also for the predators which prey upon them. In other words, high densities of prey species not only cause ecosystem instability by competing with each other, but this instability can move up the food chain and affect predators at higher ...


-1

According to "The selfish gene," animals evolved not to produce more kids than they can get enough food to rear because those that produce more kids rear fewer. The rate that nature produces food for any species is not constant. When the rate that nature produces food is increasing, the evolutionary stable strategy is for some females to produce 3 kids at ...


1

Z value is a fitted constant and it ranges between 0.1 to 0.3 regardless of the region or taxonomic groups.i.e. the slope is almost similar .Among larger areas like continent,the slope tends to be much steeper.becoz, Larger the area larger will be number of species(species richness),for larger areas the Z values tends to be 0.6 to 1.2.(NOTE:if Z is less,...


2

I don't know if this is just me, but I'd consider this a pretty badly worded question. For models of population dynamics, the rate at which the size of a population changes over time is normally accepted to be the net balance of four fundamental processes: Birth, Immigration, Death, and Emigration ('BIDE'; see for example here). Birth and immigration ...


0

I feel answers A & C are more obvious. option D is countered by Birthrate. also, migration is a temporary affair, check its meaning (An instance of moving to live in another place for a while). whereas emigration is to permanently move to a new location and populate that area.


2

As pointed out by @bshane it seems your question is answered by the definition. From the relevant wikipedia articles "A seral community (or sere) is an intermediate stage found in ecological succession in an ecosystem advancing towards its climax community." and "In ecology, climax community, or climatic climax community, is a historic term that ...



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