06. Green infrastructure and ecological landscape planning

In the northwestern corner of the oak landscape in the Stångå Valley is Linköping City. Here we find one of the largest concentrations of old oak trees in northern Europe, as well as several hundred red-listed species. The oak landscape is a popular place, both for recreation and for experiencing nature, and many Linköping residents are proud of it. Text: Anders Jörneskog

How can city and oak landscape develop sustainably together?

Linköping is a growing city, and for this growth to occur sustainably, the municipality has developed an ecological landscape plan for the sections of the oak landscape that are close to the city. The purpose of the plan is based on these questions:

  • What characteristics must the oak habitats have, for demanding species to be able to survive?
  • Is there enough area of suitable habitats, for species to be able to survive long-term?
  • Are areas with suitable habitats close enough to each other, that species can move between them?

Landscape analysis for Linköping

A few years ago the planning area was inventoried, which included recording the coordinates of oaks and other deciduous trees. In total there were 17,700 oaks and other deciduous trees with a diameter of more than 70 centimetres. All high-value areas of deciduous trees were inventoried for wood-inhabiting insects and lichens. With a starting point in the extensive inventoried material, the long-term development of oak landscapes and biodiversity has subsequently been described by way of a number of scenarios. The hermit beetle was chosen as the model species for the scenarios, because it is a very demanding species, with well studied biology. Also we know that if the hermit beetle can survive in a landscape long-term, a large number of other species can also live there.

Based on the analysis, which was conducted by Linköping University, cost efficient proposals were devised for measures that can deliver the best conservation benefits. The results show that it is not sufficient to manage the existing high-value areas with retained biodiversity; the area must also be increased. Moreover, the oak habitats are too fragmented. The greatest conservation benefits are a result of larger areas and reduced fragmentation in the green corridors identified in the analysis, which lays the foundation for a well-functioning green infrastructure.

Measures for conservation benefit

The landscape analysis has now been used since 2008, and a large number of measures have been implemented with support from it. Here are a few examples of work done on municipally owned land:

  • The oak landscape’s high-value areas are protected, and green links are identified in the physical planning.
  • All oak habitats larger than two hectares are re- stored and grazed in collaboration with roughly 25 animal keepers (approx. 800 hectares).
  • Old oaks have been cleared around, and an oak management plan including some 250 oak areas has been developed in order to systematise the management measures.
  • In woodlandry measures, oaks and their natural rejuvenation must always benefit. Oak and pine rejuvenation is today the main focus in rejuve- nation of the municipally owned woodlands, especially where the spruce bark beetle has run amok.
  • In parks, green spaces and nature reserves, planting includes oaks and the flowering bushes and small trees of the oak landscapes.
  • Residents are involved in the plantings, as they can plant their own ‘memorial oaks’ on municipally-owned land.
  • A large number of wood mould boxes, stag beetle habitat piles, fauna depots (dead wood left on the ground with the aim of increasing biodiversity) and bee beds are built in parks, green spaces and nature reserves.
  • Species present in the oak landscapes are inventoried systematically, and the population development of the hermit beetle is monitored in an eight-year inventory cycle.

It is also important to make the oak landscapes accessible to residents, and to spark their interest in the landscapes. Located near the city, the oak landscapes are attractive for recreation. New recreational facilities are frequently being established, and a large number of guided tours are conducted. Today the conservation of the oak landscapes for people, animals and plants has sound support with the residents of “Linköping – the city of oaks”.