Wild Bee Green Roof Meadow
A 500 m2 biodiverse meadow will be planted on the flat roof part of the new building, specifically designed to create a ‘habitat analogue’ capable of supporting and (hopefully) enhancing the local wild bee (and larger pollinator) population as well as providing research opportunities. The chosen habitat is Calcareous Grassland.
Calcareous grassland, is widely considered to be one of the most species-rich and important habitats for conservation of wild bees in Europe. It is identified as a (conservation) Priority Habitat in the UK Biodiversity Action Plan (UK BAP) as well in the local Peak District BAP. Derbyshire, it is estimated, lost between 80 - 91% of its species-rich grasslands from 1984 to 1999.
The planting regime will be developed in consultancy with Pictorial Meadows who have indicated a willingness to assist in with the seed mix. Pictorial Meadows are part owned by the University of Sheffield, directly benefiting from research undertaken by the University’s Landscape Dept and by The Green Roof Research Centre (based at the University) which is the leading UK centre for green roof studies.
Pictorial Meadows was founded by Nigel Dunnett - the UK’s ecological expert on pictorial meadows and green roofs, Professor of Planting, Design and Vegetation Technology at Sheffield University and a Director of The Green Roof Centre.
Pictorial Meadows were responsible for the acclaimed gardens and meadows at the Olympic Park, London where Professor Dunnett was chief designer and horticultural consultant (for more information see the Green Roof Wild Bee Meadow commissioned report).
Wild bees should not be confused with honeybees given the latter’s recent high media profile regarding population decline and publicity for roof top domestic honeybee keeping. Despite both bee types being equally threatened, wild bees are more effective pollinators, forage at much reduced distances to honey bees, thus making more use of local pollen sources, rather than heading for the nearest oil seed rape field 2 miles away - plus wild bees do not sting. Their value is now being more widely recognised (see theguardian article Loss of wild pollinators serious threat to crop yields, study finds).
The largest ever international survey of insect pollinators undertaken (a three-year study published, June 2015) reported that wild bees have become as important as domesticated honeybees in pollinating food crops around the world due to the dramatic decline in number of healthy honeybee colonies over the past half century.
Amazingly the survey found that just 2% of wild bee species now account for 80% of global crop pollination.
The scientists warned that relying on the free services of a small number of wild bee species threatens the future security of food production. The Centre for Agri-Environmental Research at Reading University commented: “At one time, honeybees were enough to pollinate most of Britain’s crops. Now there are only enough to pollinate around a quarter of them. If we didn’t have other species of bees to turn to, we would already be facing a food security catastrophe.”
As well as nectar provision, our roof meadow will provide nesting sites for solitary wild bees, even their own roof top hotel… the second option below allows observation of the bees from the inside seated area through some of the open honeycomb panels.
The potential exists for commercial rearing of wild bees - compared to honeybees, they are less-labour intensive and many more can be accommodated in a similar area. Additionally, there are established sampling methods, using solitary bees as bio-indicators, for monitoring habitat quality and diversity (of say ecological enhancement schemes or for comparing green roof planting designs) - providing both valuable and rare research opportunities.
Replacement Trees and Hedgerows
The existing onsite trees will be removed to enable the basement part of the development.
These trees were subject to a professional survey which found (with one exception) all to be individually of only low amenity (category C) value as per BS: 5837.
The most visually significant of the current trees are the group of five limes bordering St Johns Road - these will be replaced with Category A fastigiate trees. The new tress will be of greater amenity value than the present limes and improve the current street scene too.
Furthermore, the fastigiate trees trees will have greater biodiversity value by way of featuring specimens that are highly regarded in respect of their all year round Wild Pollinator/Nectar provision.
This approach will be extended to include the hedgerow, which the Ecological Asst presently regards as species poor and of no ecological value.
Bat Provision and Monitoring
Roosting space for bats will be provided through the installation of Ecosurv Habibat Bat boxes.
Habibat is an integrated, bespoke, unobtrusive and aesthetically pleasing bat box with an internal roost space which is expandable as Habibats can be joined side by side to increase this. They are incorporated into the fabric of a structure as it is built and faced to match the external finish of the building (existing stone).
Habibat is a unique partnership between the Bat Conservation Trust, Ecosurv and purchasers; a portion of the profits from each Habibat sold will be reinvested into the Habibat scheme to improve accommodation for bats through design refinement based on reported monitoring of their use. Ecosurv have expressed a willingness to work with us post planning to maximise the value of site for both bats and monitoring.
Monitoring is normally reliant on night time observation by volunteers. Assuming collaborative research partners are found, we would consider automating the process through the use of mounted thermal imaging cameras, thus guaranteeing a record of all night time activity relating to the Habitat boxes.
Broadening the scope of monitoring to record bat activity over the green roof is a natural extension of the above. The potential for green roofs to provide habitat for bats was noted by Natural England in 2003 and expanded on by the Bat Conservation Trust (BCT, 2012). Further investigations have been limited to only a few studies (Pearce and Walters, 2012). These studies concur that if implemented and managed correctly, green roofs can provide foraging habitat for bats. However more data is needed in order to inform evidence based urban conservation policy and implication. Therefore, the gap is clear for continued research into this area of urban biodiversity.
Monitoring green roof activity involves the real time bio-acoustic recording of bat calls via a full-spectrum ultrasound recorder. This could be permanently mounted on the green roof or located in the building if connected to an external microphone. Recordings are saved to SD card without gaps as a triggering system allows the device to automatically start recording when a sound is detected or falls within chosen frequencies. GPS, time/date/temp stamps can be added to each recording.
Living Walls (no longer included)
It is worth mentioning that our Pre‐application plans submitted to High Peak Borough Council in September 2014 included additional green infrastructure in the form of living walls, as they provide many benefits beyond increased biodiversity habitat, including air purification/dust suppression, reduced urban heat island effect and carbon dioxide sequestration capacities far in excess of trees (our living wall scheme equated to 60 trees).
Specifically, we proposed 1,000 m2 appx to cover the two lesser (non road facing) elevations. There size would have made them the largest hydroponic vertical garden in the UK, the fourth biggest in Europe and in the World's Top 10 existing single building installations (as at Sept 2014).
More excitingly, acclaimed French botanist Patrick Blanc - universally credited as the modern inventor of the vertical garden and whose past work is World renown and visually are attractions in themselves ‐ had agreed to design these - examples of his previous commissions are shown below.
Sadly, High Peak Borough Council’s blunt response to their proposed inclusion was that they ‘should not form part of any future planning application’.