The natural environment is self-sustaining and adaptive, with populations rising and falling based on available resources. However, human activity like pollution, deforestation and overexploitation can damage the environment. Unnatural environments like cities require maintenance and resources, releasing pollutants and waste. While providing benefits like food production and transportation, current human systems are unsustainable and harm both natural and unnatural environments locally and globally.

1. The environment
The environment is something you are very familiar with. It's everything that
makes up our surroundings and affects our ability to live on the earth—the
air we breathe, the water that covers most of the earth's surface, the plants
and animals around us, and much more.
In recent years, scientists have beencarefully examining the ways that
people affectthe environment. They have found that we are causing air
pollution, deforestation,acid rain, and other problems that are dangerous
both to the earth and to ourselves. These days, when you hear people talk
about “the environment”, they are often referring to the overall condition of
our planet, or how healthy it is.Everything is an environment. An
environment essentially means "a place".You're probably referring to a
natural environment, though. The advantages are many and the
disadvantages few.
A natural environment is self-sustaining,self-replenishing,and adaptive.
Plants, animals, fungus, bacteria, etc are born, die, thrive, and do poorly all
based on the current circumstances of the natural environment. An easy
example, is that if there are far too many herbivores, such as deer,then
food sources forthe deer will start to grow fewer, resulting in the deer
population going down do to starvation or similar things. In a natural
environment, many organisms can be used for food for us as well as food
for many other organisms we like, such as song-birds or foxes or
monkeys.
However, in a natural environment, taking parts of it away or disturbing it
excessivelyhave negative impacts on it and it's not simple to aggressively
exploit it without destroying it.
In an unnatural environment, they tend to look far less appealing to us.
Take, for example, a city street. Here in Canada, the streets are often
made of asphalt which offgassesnasty, smelly chemicals and the asphalt
must be repaired and replaced eventually at great labour costs.
Furthermore, the way we make streets is quite harmful to the environment,
both natural and unnatural, both locally and worldwide. Our unnatural
environments are unsustainable in their current forms. Most of them are,
anyway. Also,without complexcommunities of life forms all connected in a
balanced chain, things aren't self sustaining and self cleaning. There's a

2. great deal of garbage that humans discard that will not break down on its
own. It takes labour to collectsuch things and, often, dispose of them in
larger and larger dump sites. We typically grown ornamental plants like
kentucky blue grass, various small annual flower speciesas well as trees.
These plants, for the most part, are not self-sustaining where they are.
They need to be watered, they need to have more competitive species
controlled,they often need fertilisers.This is another drain on labour as
well as being polluting.
The advantages to our unnatural environments are quite obvious. We grow
most of our food in highly unnatural factory farms. We use roads to
transport ourselves.We live in houses, often with unnatural yards which we
find attractive. We exploit what we can find, such as minerals to produce
commodities we desire.