"It's the economy stupid - that's what will determine the electoral prospects of the Liberal Democrats".  This was the clear message from economist Vicky Pryce at a fringe meeting yesterday.    Forget over-used phrases like "maximum differentiation" or "focus on delivery", I sensed that neutral political observers believe that the state of the economy will decide the fate of the coalition partners at the next election.

Which is why economic recovery featured prominently in conference hall debates and the fringe.  And the green economy is getting a decent airing.

There are two sides to the green economy debate.  One that focuses on clean energy and...?  Well the other side which focused on the natural environment is largely ignored.

The low carbon economy story was well told in a new Green Alliance publication which we supported.  It's conclusion was that "quietly and without fanfare, green business has become a UK success story, at home and abroad.  We now export more green products and services to our competitors than we import from them, and we have become the green financing capital of the world."  It was impressive to hear the Director General of the CBI, John Cridland, singing convincingly from this hymn sheet last night.

But what about the role of nature and the environment?  What contribution does it make to the economy?  Recent studies have shown that the natural environment supports almost 750,000 full time equivalent jobs and over £27.5 billion of economic output across the UK.  And we're playing our part.  Our reserves across the UK attract an estimated £75 million into the local economy and 2,000 local jobs.  

These benefits are more often than not located in more remote, rural or coastal areas, where economic opportunities tend to be fewer and less diverse.  The greatest impact delivered by conservation come from tourism spending and from the two and half million visitors to our reserves - nearly a fourfold increase in a decade.

So what should politicians make of this? 

First, there must be an acceptance that we need a new approach to economic development and prosperity.  Such an approach needs to be resilient to shocks, respect environmental limits and have the potential to deliver sustainable prosperity over the longer-term.  We cannot do that without greening our economy and we can't green our economy without conserving the natural world.  Want to know how to do it?  I'd recommend the New Anglia Green Economy Pathfinder which does a good job at combining both sides of the green economy debate.

Second, once their conference week is over, every delegate should go to a local RSPB nature reserve, recover from the stress of a hectic week, reconnect with wildlife and spend lots of their money in the local shops and pubs.

And I shall prescribe this remedy to my hard working parliamentary team.  But not yet, they need to start packing their bags for Manchester and the Labour Party conference next week.