Saturday, 2 November 2013

Biodiversity in Sidmouth: "Is planting a million bulbs a 'good thing'?"

A recent posting considered the planting at the Sidmouth Beach Garden:

'Biodiversity' is a huge topic and there is perhaps poor understanding of exactly what it means... 
Over manipulation of environments by ourselves may have adverse effects...
We need to be careful about where our introduced  genetic material comes from...
Futures Forum: Biodiversity in Sidmouth: Beach Garden

This could mean introducing too much of a 'good thing'. 
This note has been received from one of our correspondents:
Aside from the choice of genetic material for introductions, mass plantings of any one plant may be corruptive to biodiversity.
Some commercially bred plants may not provide any food accessible to insects. Others may be very attractive to insects and as a mass planting will be favoured by insects at flowering but in so doing their presence may be detrimental in reducing pollination of other local plants in flower at that time. 

This might seem rather churlish, considering the enthusiasm and involvement by the wider community, as reported in another recent posting:
Futures Forum: Keith Owen Fund: one million bulbs: community planting: reports

Moreover, other parts of the country consider it is also seen as a 'good thing': 

The aim is for the community to become more actively involved in their local park, for example they will take part in environmental projects such as tree and bulb planting to help improve the biodiversity in the area.
Newtownabbey Borough Council - Outdoor Areas: Love My Park Scheme

However, there are concerns that some kinds of planting can actually be bad for biodiversity:

What are the main threats to biodiversity?

Addressing the major threats to biodiversity, including those arising from invasive alien speciesclimate change, pollution, and habitat change

Five main threats to biodiversity are commonly recognized in the programmes of work of the Convention: invasive alien species, climate change, nutrient loading and pollution,habitat change, and overexploitation. Unless we successfully mitigate the impacts of these direct drivers of change on biodiversity, they will contribute to the loss of biodiversity components, negatively affect ecosystem integrity and hamper aspirations towards sustainable use

.Indicators for trends in nutrient loading and invasive alien species have been identified under the focal area addressed here, and are described below. Information on habitat change is provided by the indicator trends in extent of selected biomes, ecosystems and habitats. Overexploitation is discussed under the focal area on sustainable use.
6. What are the main threats to biodiversity?

What is meant by 'invasive alien species'? 
Typical are Spanish bluebell - Hyacinthoides hispanica - and Japanese Knotweed - Fallopia japonica:

Strictly speaking, however, any 'invasive alien' is simply a 'non-native' or 'non-indigenous' species:
Invasive species - Wikipedia, the free encyclopedia
Introduced species - Wikipedia, the free encyclopedia

What about 'non-native' bulbs? Here's the beginning of a long discussion thread:

In praise of … daffodils

What's so wrong with larger, louder varieties of the native daffodil?

Rural bling, lamented the man on the radio a few days ago, of the noisy golden trumpets that are now lining roads and gardens across the country. 
Narcissus pseudonarcissus, the native British daffodil, is being shouldered out by larger, louder varieties. 
It is easy to see why the daffodil, symbol of hope and rebirth, is associated with the vanity of the Greek youth Narcissus, transfixed forever nodding in approval at his glorious reflection. And in an ideal world, nothing could be more wonderful than seeing the early drifts of snowdrops on the verges of country lanes replaced by the delicate, pale golden heads of our own native daffodils
But left to themselves, these natives want the damp, misty woodland of the Welsh borders, not the rubbish-strewn roadsides of England's highways. In this latter, unpromising setting, it takes all the vigorous vulgarity of February Gold or Cheerfulness to be seen over the strips of tyre and the fast-food debris that would overwhelm the more fastidious natives. 
And although the daffodil hybridises easily, there is, according to Natural England, little evidence yet that the genetic identity of the native is being damaged. It might also be worth remembering that the narcissus pseudonarcissus that so impressed Shakespeare and Wordsworth may well be an immigrant from Spain – it just got here earlier. It is really just a question of botanical aesthetics, and when it's robust bling rather than the debris from last night's takeout, then bling is better.


In praise of … daffodils | Editorial | Comment is free | The Guardian

In the case of planting bulbs bought en masse from an outside supplier, there are further issues:

Wildlife habitats - Leith Community Crops in Pots

See also: Futures Forum: Biodiversity

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