The Ecological Value:
In many ways the ecological and environmental values would normally be considered under the same banner. I argue this is not the case for the ease of this valuation – in which the ecological value is primarily a value placed on the trees benefit to other immediate flora and fauna. The environmental value is with regards its attributes as an entity in terms of global benefits and systems to alleviate human activity, the need for this division is further detailed below. But it is important to note the work and fast growing stature of Teeb, (The Economics of Ecosystem and Biodiversity), which due to the global terms within its framework needs to combine the above criteria.
The above is a link to the Teeb website.
The importance of Teeb for practitioners, governments and all professionals within the spectrum of land and natural environment industries is hard to contemplate at the present moment. It has the ability to fundamentally change attitudes to ensure that sustainable management is the only route forward because it simply allows for the highest financial values to be achieved.
The ecological value varies significantly due to location. Firstly a tree within a forest or woodland – the individual tree is part of a much larger ecosystem, where the value can only be attributed to the forest as a whole (as per Teeb), there will be an ecosystem for that individual tree, but its value is considerably less than:
A tree which stands alone or as part of a hedgerow, copse or other environment that can be classified as green highway for flora and fauna.
For reference I am using a US system, that appeals due to the connection with the Helliwell system for Amenity Valuation. This system is independent of factors which cross the boundaries of my chosen valuation criteria, (asides from water run off, which will be discussed further within the Environmental Valuation).
All the values have been changed from USD in GBP at the current rate of 0.63016
The dbh of two trees combined = 241cm² converted into inches (this simplifies the calculation as the Frank Reeves system uses inches) this equals =37.35inches².
Basal Area (3.1416 X (dbh/2)²)
= 1095.65 inches². The Frank Reeves system I am using uses a value of 3 USD in 1988. Using an inflation calculator, this value in 2010 is 5.53 USD, converted into GBP = £3.48.
Thus the baseline ecological value of the two limes = £3818.10
Frank & Reeves then use deduction tables, see link above, to reduce the price to reflect its position with regards certain factors.
Using the tables I have reduced the value accordingly. Which brings the total to = £2749.03.
One factor I wanted to add to this calculation was the huge variance found between tree species in terms of flora and fauna which can be found on any particular individual tree. This data can be found here:
As such I devised a very basic score sheet using the mean total of species found on a particular tree of 214.
|No of Insects, (including mites) and lichens:||Value + / –|
|0 – 100||0.6|
Oak trees have a phenomenal quantity of insects and lichens recorded (747) compared with Rhododendron, (0), this simply adds in a fair value accrued according to species. Atlantic temperate oak woodland is Europe’s richest ecosystem and should be allowed a doubling of value in order to reflect this.
The Lime trees total is 114, thus a reduction of .8.
Total of Ecological Value = £1983.22
SUB TOTAL £10486.83