Wednesday, 30 May 2012

Is "Bringing Woodland Back into Management" good for the Climate?

A number of current forestry lobbying documents include the suggestion that the global atmosphere would be benefited if currently unmanaged broadleaved woodlands in England were brought into active management for woodfuel. This post seeks to explore whether there is scientific evidence in support of such a policy.

The "Our Forests" lobbying group provide an example of the assertion:

"We need to bring our neglected woods back into productive rotation to kick-start local, low-carbon economies, boost rural employment, and create the right conditions for wildlife."

In stating this, Our Forests draw upon the comments of Wildlife link on the Forestry Commission's Woodfuel Strategy:
 
“The Woodfuel Target could play a key role in contributing to a new low-carbon economy and in addressing the urgent need for positive management of many woods and forests across the country.”


The Woodfuel Strategy itself, a product of a civil service careful to ensure "evidence based policymaking", does not make such a broad claim. 

The suggestion is that burning wood would reduce fossil fuel usage, while the woodland growth would re-sequester the CO2 emitted as a result of burning the woodfuel. However there is some doubt about whether the scientific evidence supports such a general policy.

The most comprehensive assessment of the potential role of UK forests in mitigating climate change is the "Read Report" published by the Forestry Commission in 2009. This report set out a number of Forest Management Scenarios (FMS). One of these, (FMS-D) dealt with the bringing of unmanaged woodlands back into management. It is shown by the light blue line on the graph (reproduced from Read) below.






Here is the related quote from the "Read Report" 
"Bringing unmanaged woodlands back into management (FMS-D) leads to significant net emissions (up to 5.5 MtCO2 year1) from forest biomass and soils relative to the BAU scenario. However, this impact is reduced when total abatement is considered, with the result that over the full course of the simulation to 2150..., FMS-D provides a small amount of additional abatement (0.3 MtCO2 year1)."

The implication is that a programme of increased management of broadleaved woodland in England of the type modelled, could result in a negative net effect on atmospheric CO2 for a long, perhaps crucial, period.

The reason given for this (perhaps counter intuitive) result is that:
"the majority of unmanaged woodland is slow-growing, broadleaved woodland for which both levels of production (and therefore substitution) and rates of recovery in carbon stocks following harvesting are smaller than for faster growing conifer species. The age and current growth rate of a stand brought back into management will also have a profound effect on the balance between substitution benefi ts and recovery of carbon stocks, requiring more detailed knowledge than available as input to this national scale evaluation."

Similar effects have been reported for slow growing boreal forests (Holtsmark, 2011), and more generally from increased additional forest biomass harvesting (Schulze et al 2012).

 

Conclusion

In the absence of the more "detailed knowledge" referred to by Read et al., carbon science does not appear to support a general policy of increasing the management of broadleaved woodland in England for woodfuel, in order to mitigate climate change. The global atmosphere might be better protected by refraining from human interference in such woodland, leaving nature to sequester carbon by continued growth.

Refs:

Read, D.J., Freer-Smith, P.H., Morison, J.I.L., Hanley, N., West, C.C. and Snowdon, P. (eds). 2009. Combating climate change – a role for UK forests. An assessment of the potential of the UK’s trees and woodlands to mitigate and adapt to climate change. The Stationery Office, Edinburgh.

Schulze, E.-D., K├Ârner, C., Law, B. E., Haberl, H. and Luyssaert, S. (2012), Large-scale bioenergy from additional harvest of forest biomass is neither sustainable nor greenhouse gas neutral. GCB Bioenergy. doi: 10.1111/j.1757-1707.2012.01169.x

Holtsmark B (2011) Harvesting in boreal forests and the biofuel carbon dept. Climatic Change, Available on-line:
http://www.ssb.no/publikasjoner/pdf/dp637.pdf

Monday, 20 February 2012

Can you have trees without foresters?

It's sometimes interesting how "active" (or do I mean hyperactive?) foresters can be. There is a mindset which some writers have called the "imperialistic" approach to nature (Peterken, 1996). A plan has been drawn up and the hand of "man" will impose order on nature. The alternative approach can be called "arcadian" - "let's leave this to nature", or "what is nature doing here, do we really need to interfere?"

On the other side of the road from this site money and effort has been spent planting conifers which may damage and confine a broadleaved feature. 

It seems that just on this side of the forest road "The Plan" says "Here There Shall be Broadleaves". Let's be clear, this is certainly the right strategy, we are inside or just on the edge of the "Broadleaved Woodland Core Networks" zone.

As far as I could tell, inside the tree shelters are planted ash trees. Now these shelters are pretty expensive, their costs are debateable even where you really need to plant trees. But do you here?

You will note that the area is pretty small and surrounded by mature broadleaved trees. These are shedding seed into the area below and around. Doing absolutely nothing is likely to result in a grassy brambly patch for a few years through which birch, oak (and I saw some Holly) have already started regenerating. 

Admitedly I saw no Ash. If you really thought Ash should be part of the mix you would need to plant some. 

Maybe three?

Tuesday, 14 February 2012

Welsh Forestry Employment, Jobs and Statistics

Are there Really 10,000 jobs related to how Welsh Forests are managed?

There are various numbers going around for how many people are employed in Welsh forestry:

Western Mail  6 December 2011 had the Wales Forest Business Partnership claiming 16,000.

This seems to come from the FCW website.  The background research seems to be this (16,300) from Jaako Poyry.

Western Mail 3 November 2011 "employs 10,000 people directly and 8,500 more indirectly"

That one originates from a joint study by the Forestry Commission and the timber dominated industry lobby group ConFor.

They were both printed in the Western Mail so they must be true.... 

What appears to be happening is that lobby organisations are understandably trying to talk up the importance of their industries, in order to gain political influence. Spin doctors at work.


So what is the truth? How many jobs depend on the way in which the forests are managed in Wales?

There IS a published source from Forestry Commission Wales:
Woodlands for Wales Indicators 2011 (pdf takes time to load) 



On first sight the total, 9,141 makes ConFor's round 10,000 look pretty fair.

BUT: 4,781, more than half, are employed in pulp and paper. That's two mills, both using waste paper, so really nothing to do with Wales's forests? (Note: until ten or fifteen years ago the big mill at Shotton did use wood, so you could argue that it might again? But if it did how much would be Welsh?) 


So knock them off  and you are down to about 4,500.

BUT how many of the rest actually relate to the Welsh forests? Where does the wood come from?





This chart makes it clear that certainly in terms of volume, about 60% of wood supporting the 1,356 jobs in primary processing comes from outside Wales.

That would make about 550 jobs.

Only 5% of the volume supporting the 2003 jobs in secondary processing is from Welsh forests. 

That might be 100 jobs.

Totalling these figures gives us about 1,900 jobs.

Or; if you look at the chart on the left above on business numbers and thought that could be a better proxy for jobs than volume it would give a higher number for primary and secondary processing taking the figure to around 3,000.

Does that have a common sense ring of truth? Well about a million cubic metres of timber are harvested every year in Wales. Much of that is highly mechanised  it might not be much more than 100 mechanised harvesters doing 10,000 cubic metres a year each. Carrying 1,000,000 cubic metres will take 50,000 lorry trips, that's less than 200 lorry drivers at 300 trips a year? Primary processing is also very labour efficient. One mill employing about 120 people can process nearly 100,000 cubic metres of timber. I'm over simplifying here, the harvesters and lorries have mechanics, there are sites which are labour intensive with chainsaws, small specialist mills with more employees per metre of timber etc. But overall we seem to be, being reasonable, in the low thousands?

FC Wales received £24.7million last year from the Welsh Government.


'Political Industrial Complex'?
What is going on is politics. The industrial forestry lobby need to maximise their political influence. This linked in the past with the relationship with FC Wales, which was significantly committed to commercial clearfell and conifer restock forestry. The merger of FC Wales with the Environment Agency and the Countryside Council for Wales may mean that people who care about, and are expert in water, landscape, and wildlife issues become more closely involved. The attention of politicians can be gained from talk about jobs. It's in the interests of the industrial forestry lobby to "massage up" the numbers (I've sat in meetings watching it happen). The reason is (we are in Yes Minister territory here) a politician will want to look as if they are taking big account of employment.  

So if a lobby group gets some biggish numbers accepted by the Western Mail and even the BBC, and current in the minds of AMs, there will be worried, or at least engaged, politicians. 

Sir Humphrey: "Or look as if he's TRYING to reduce it. Whereas he's only trying to look as if he's trying to reduce unemployment. Because he's worried that it doesn't LOOK as if he's trying to look as if he's trying to reduce it."