Wednesday, April 8, 2009

Ant Robots



Robot technology seems to be leaping forward right now.  

Not sure when we will need to program in Asimov's three laws of robotics, but it won't be long.

Hat tip: Myrmecos blog

YouTube and Robot credit: Kåre Halvorsen (aka Xenta) from Norway

Monday, April 6, 2009

Dead Wood is Needed for Living Forests

What do we mean by a word like 'Waste?'

Generally we mean that it is useless and is a burden just to discard.  The less the better.

Why then do we use this word to refer to the dead standing or fallen wood in our forests?  It is anything but waste.  Rather, it is a vital resource for countless animals, plants and micro-organisms in our forests.  Its decayed fibre contributes organic material to our forest soils and helps to buffer soil pH.  It also acts as a water reservoir in forests where drought is common.

It can be called it waste only if we do not understand its function in forest ecosystems or it can be called waste by those who want to use it for other purposes.  This is the term used today by the BC government and the bioenergy industry to describe this resource.

Despite the desire by the modern forest industry to emulate (i.e., imitate) natural disturbances in log harvesting operations, the massive removal of tree biomass in no way emulates what normally occurs in nature.  How much biomass can be removed before we see a serious disruption to the ability of forest soils to regenerate new growth is uncertain.  Traditionally though, forestry operations in British Columbia have left more wood behind on cutblocks than occurs most areas of the world.  Still, this may not be enough.

Now, the bioenergy industry wants to greatly reduce the volume of remaining wood.  On a visit to a local bioenergy facility I once heard a manager talk about obtaining a Swedish machine to scrape and bundle the smallest pieces of wood from the forest floor.  Worse, the claim is made that this is a 'Green' technology. 

This month the Williams Lake Field Naturalists will present a resolution to the Annual General Meeting of the Federation of BC Naturalists.  It reads:

"Whereas, coarse woody debris (CWD) is a fundamental component of forest ecosystems, critical to:

1) providing habitat to many dead wood dependent organisms (e.g., fungi, insects, vertebrates) which in turn support a broader food web (e.g., insectivorous birds, bears);

2) providing energy to support forest resilience (e.g., ability to resist extensive damage from forest pests, climate change or invasive species);

3) providing water storage in ecosystems frequently experiencing drought;

4) providing pH buffering capacity to forest soils which become acidic as a result of biomass removal;

5) providing nutrient and structural components to forest soils in a province noted for low-productivity soils.

Whereas, management guidelines for CWD retention under the Forest and Range Practices Act are inadequate for protecting this resource under existing harvesting pressures, there is concern that additional plans for biomass removal by the bioenergy industry will exacerbate this problem.

Be It Resolved:  That Nature BC communicate to the Government of BC the need to develop a science-based woody debris (organic matter) management system with the view that maintaining CWD is fundamental to the sound ecological management of our forests."

I hope this helps to raise this issue in the minds of BC naturalists.

Photo Credit: Me




Energy and the International Space Station

Last week the International Space Station unfurled the last of its 8 paired solar panel arrays (each array is composed to two long panels, 5m by 34m long). The photo above, taken last week by the departing space shuttle, Discovery, shows all of the panels now in place.

How much energy does it take to run the space station?  Well, basic life support and essential operations on the station requires about 20 kilowatts (kW).  A single array generates around 15kW but they are exposed to sunlight only half the time.  Thus, approximately three of the 8 arrays are necessary for life support.

A typical home in Canada uses a bit more than 1kW on average (about 11,000 kWhr/yr).  This means that the 5 arrays not required for life support would provide enough energy for approximately 35 homes. 

How much did those arrays cost?  Each of the eight run about $300 million.  The station shown above is now estimated to be worth $100 billion.

Worth it?  I don't think so.  For that cost we could be seriously exploring the solar system using robots.  Is there life under the ice of Europa (one of Jupiter's moons) or on Titan (a moon of Saturn)?  These are questions 100 billion could have answered.

Photo credit: NASA, Discovery (STS-119, Shuttle Crew, March 25, 2009)