G'day all,

Of late we have had some debate attached to the issues of Land Clearing. I think for this reason it would be useful to begin a topic on our interactions with our environment that transform it in a degrading way ecologically speaking.

For me five of the big ones have been,

The clearing of woody vegetation to provide agricultural and living space.

Urbanisation of natural areas and of rural (already modified) areas.

Pasture Improvement (Ha!) - whereby native grassland is managed away through the application of seed and fertilizer.

Overgrazing - transforming landscapes by impacting grassland to such a degree that it fails to maintain itself. You can get succession to woody plants, weeds of many varieties and to annual grasses (also weeds).

Plant and animal introduction - we can do damage hands free and create situations that run away from us.

The way these happen and to what level varies a lot. But they are widespread over many areas.

Does anyone have any to add or comment to make on any of these?

- Stephen

My only comment is in the context of a thread titled "The Big Ones" urban clearing hardly deserves mentioning compared to the big ones of lot feed farms and forestry. The emerging bio fuels industries would make another good thread.

This post has been edited by NSW_Farmer: Sep 15 2007, 06:58 AM

I am also actually thinking of urban clearing as impacting on particular ecologies along the coast. In respect of these it has been enormous.

Forestry can have positive and negative impacts depending on how we do it.

Lot feed farms have nothing but negative impact altogether as you have to put plus signs between the different levels of impact that they have. Cropping+Feed lot space+pollution+health issues = Why?

Addiction to economic growth has meant that these impacts continue to propagate as we falsely equate economic growth with social health and well being while at the same time wasting much of what we gain on consuming very questionable products and services that do little for us in any real sense.

As for urbanisation again - subdivision continues in already heavily impacted zones where ecologies are present that become increasingly scarce as land sales are used to subsidise our governments/councils/lives.

Water resources are further drawn upon in areas where they are already stretched at a catchment level - causing the likes of me to become baffled at why we make a bad situation worse.

Anyway - "The Big Ones" is actually meant to be added to so is this what you are adding?

- Stephen

True, adding up should include all metrics availiable, I just don't think we should worry too much if we can't get accurate figures for urban areas as they as so small in acres compared to the whole of Australia... Though point taken about humans living along the water mainly.

In Victoria, land clearing for agriculture - including forestry - has just about ceased.
More vegetation is cleared for urban development than agriculture.

Stephen - if you want to add to your list, I have a few suggestions.

• Alteration of disturbance regimes - especially fire - to natural ecosystems. Too much fire in northern Australia, too little fire in southern Australia. We're talking millions upon millions of hectares here.
• Bushfire. Victoria has had one-quarter of its forests burnt in high-intensity, uncontrolled wildfires in the 5 years. The resultant soil erosion turned several waterways into molten chocolate, which brings me to ...
• Alteration of river flows due to damming, farm dams, irrigated agriculture, pollution of waterways etc. Just because we can't see whats going on underwater, doesn't mean that there's nothing there!

I'm sure there's more, but I'll get back to you.

You could be right Timjim, however I would like to see the statistics. In the last 10 years in Northern Victoria 3/4 of the last remaining grassland and grassy-wetland ecosystems have been cleared for cropping. Last year at least 1000 hectares of native grassland was cleared in northern Victoria. Local governments fail to enforce the clearing laws that have been in place for more than a decade. Some of these grassland sites that have recently been cleared were previously never cultivated, pristine, beautiful grasslands, containing dozens of species of threatened animals and plants.

Witnessing this over the last ten years has ruined my view of the average wheat farmer, to the point where I cannot feel sympathy towards many of them after yet another failed wheat crop this spring.