We gardeners are all Eco-managers. We take our piece of the planet and we accelerate, sustain and then abruptly halt natural ecological cycles. Even non-gardeners do this, though they may not pay as much attention to it. Take Mr Lawnlover for example:(I'm making this imaginary, yet stereotypical person, male because I'm female and it's my blog!)
Mr Lawnlover will sow grass seeds. He will create a mono-culture - a patch of ground that grows only one species (something which nature abhors nearly as much as a vacuum) thus decreasing habitat options for local wildlife. Then he will add fertilizer, usually way too much fertilizer, so that when he over-waters this piece of ground, (as he is sure to do) lots of fertilizer will get washed into the nearby streams, rivers and eventually the sea, causing a burst of plant life in these waterways that dies quickly and rots. This decomposition leads to oxygen depletion in that area and suffocates any animals living within that body of water. A lot of (scientifically ignorant) folk don't realize that fish do need oxygen even though they live underwater.
So, now that Mr Lawnlover has created a mono-culture and poisoned the water ways, what does he do when the grass actually grows? He cuts it and then throws away the cuttings of grass that he so lovingly nurtured to grow! I wonder what aliens observing our planet would think of that practice? Probably they'd put it on the shelf below the one containing such articles as "A study of humans strapping themselves to boards and sliding down mountains." This lower shelf would be labeled "Stupid Stuff That Isn't Fun."
In nature, the cycle would work like this - Grass grows, uses nitrates and other nutrients in the soil, some dies and releases the nutrients back. We could suggest to Mr Lawnlover that he mows his lawn and leaves the clipping on it, thus reducing the need for adding fertilizers (and drowning fish). The mono-culture issue would require a little more educating of Mr Lawnlover...
So how do we gardeners differ from Mr Lawnlover?
Some of us only differ in that we eat what we cut - i.e. harvest. A bed of lettuce is still a mono-culture.
When deciding what fertilizer to use ask yourself these questions:
Were fossil fuels used in the producing of this? e.g. Natural gas in the production of ammonia in the Haber process.
Was water used in the production of this? e.g. Growing alfalfa pellets
Was heat needed? e.g. Like both of the above processes - heat of course being derived from fossil fuels.
How far was this product shipped to get to me?
If you are making your own compost then you are not using fossil fuels or water (or a very small, insignificant amount of water) and you are helping the environment and saving money too. What's not to love?
Using compost made from our own kitchen scraps and yard clippings is as close to emulating the nitrogen cycle that exists in nature as we gardeners can probably get. Sure, you may have to add a little manure or other nitrogen compound source to replace what you've extracted especially at this time of the year, when temperatures cool causing chemical reactions in the soil and plant cells to slow down. Remember, as managers we're delegating. In my case, it's to the cattle that provide the manure!