This is a guest post by James Brown, PhD stu­dent at Queen’s Uni­ver­sity Belfast.

This com­ment has pre­vi­ously been pub­lished on QuBio blog of the School of Bio­log­i­cal Sci­ences. It is the expres­sion of the author’s thoughts and expe­ri­ences and as such is acknowl­edged as a fruit­ful con­tri­bu­tion to the dis­cus­sion on bio­di­ver­sity off­sets. If you want to react or clar­ify your own posi­tion (under­pin or dis­prove), please leave a reply below!

A pic­ture I took in Banagher Glen, an ancient wood­land, on my sec­ond day of sampling.

As some­one who is cur­rently study­ing the genetic vari­a­tion in native Irish trees I require good mate­r­ial for sam­pling as such I plan to go to nat­ural ancient wood­land to col­lect my sam­ples. As part of my back­ground read­ing I recently came across a num­ber of news arti­cles about the process of bio­di­ver­sity off­set­ting. In basic terms it involves the destruc­tion of a wood­land or other ecosys­tem for prop­erty devel­op­ment or other rea­sons with the cre­ation of a new wood­land else­where. The idea is that no diver­sity will be lost due to the cre­ation of this new wood­land and in some cases it may be jus­ti­fied by the promise of build­ing a much larger wood­land. There are cur­rently six pilot schemes test­ing off­set­ting in England.

So what’s the prob­lem then you might ask?Well the prob­lem is that it doesn’t work like that. It is not a sim­ple black and white process wherein you remove one wood­land, cre­ate another and this doesn’t have any neg­a­tive impact. Liv­ing trees and shrubs are sup­ported by and they them­selves sup­port a wide range of other organ­isms includ­ing those in the soil such as fungi as well as organ­isms which feed on them, bac­te­ria, yeast, nema­todes and mites which are asso­ci­ated with both live and dead roots, those which inhabit dead areas of wood includ­ing fungi and inver­te­brates, epi­phyte com­mu­ni­ties which exploit all sur­faces of trees such as lichens and mosses, ani­mals which feed on plant prod­ucts for exam­ple nec­tar along with plants them­selves as well as ani­mals which feed on fungi and ani­mals which live in the plants. It would be impos­si­ble to repli­cate the exact same ecosys­tem else­where. Not to men­tion the loss and inabil­ity to repli­cate the genetic diver­sity con­tained within ancient woodlands.

There is also the issue that wood­lands them­selves are part of a larger ecosys­tem so remov­ing one from an area could have neg­a­tive impacts on the sur­round­ing area. Wood­lands pro­vide a whop­ping 17 dif­fer­ent ecosys­tem ser­vices accord­ing to the Mil­len­nium Ecosys­tem Assess­ment. These include pro­vi­sion­ing ser­vices such as tim­ber, reg­u­lat­ing ser­vices such as air and water reg­u­la­tion and cul­tural ser­vices such as recre­ation and tourism. By remov­ing a wood­land these ser­vices may be lost from an area com­pletely or only par­tially ful­filled by a newly cre­ated wood­land. In some cases wood­lands may help pre­vent flood­ing due to their struc­ture and the greater uptake of water by trees. Thus their removal may put areas at risk.

In terms of the cre­ation of new wood­lands there doesn’t seem to be any clar­ity as to how this would be car­ried out. For one exam­ple where would they get the seeds from? Would they get seeds from the local area or would they import because it might be cheaper? There is the issue that they might inad­ver­tently import infected mate­r­ial to cre­ate wood­lands which would cause even more dam­age by spread­ing dis­ease to other areas. There is also the ques­tion of enforce­ment, who will make sure that devel­op­ers keep their promises? Also when exactly does the new wood­land get cre­ated, is it after the destruc­tion of the old one, is it after the devel­op­ment of what­ever is replac­ing the old one? And finally what fac­tors deter­mine whether or not a wood­land is eli­gi­ble for destruc­tion? Already in Eng­land there is con­tro­versy over plans to destroy an ancient wood­land in order for a petrol sta­tion to be built.

Bio­di­ver­sity is a key part of life and is very valu­able but by plac­ing mon­e­tary val­ues on things such as wood­lands it gives the false impres­sion that they can be traded along with the idea that big­ger is bet­ter which is not nec­es­sar­ily the case. The prob­lem is with a grow­ing global pop­u­la­tion more land is needed for devel­op­ment and so solu­tions need to be found in terms of find­ing areas for new prop­er­ties. Bio­di­ver­sity off­set­ting should not be that solu­tion in the case of vet­eran or ancient wood­lands. If bio­di­ver­sity off­set­ting is to be used then clearly enforce­able rules are required to ensure as lit­tle dam­age as pos­si­ble is done to our already dwin­dling ecosystems.