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I'm studying the impact of green wedges (red outline on the figure) on weather parameters in Copenhagen area. What I want to do is check how spatial redistribution of future afforested areas enacted by government (green and yellow dashed polygons) would alter the weather parameters if instead of being scattered around, they would form solid, continuous green wedges.

What I'm looking for are tools/plug-ins that would allow me to redistribute the overall area of enacted forest patches and feed them into the wedges, by filling the 'empty' areas between forest (green) and urban tissue (pink), based on certain criteria (mainly wind direction and area).

Let's say I would like to supplement the most southern wedge with 5 000 h of new forest. Continuously filling the area from the inner city - outwards. Sort of like pouring specific amount of water into the glass.

Is that possible? Else all I can think of is doing it manually and scooping out polygon piece by piece to get the desired areal.

EDIT: I don't want to keep the original shapes of redistributed areas. I just need to redistribute their total area to create a continuous forest tissue. Enacted afforestation patches account for 18477,25 h in total. This amount needs to be redistributed and it's constant.

EDIT 2 (dof1985 questions): None of the old forest is going to be removed. The green wedges I referred to (the red outlined areas) are part of the urban development plan for Copenhagen. However, due to many reasons these wedges are disappearing and being built-up.

So project is more about supplementing/expanding the still existing forest tissue and showing its influence on weather conditions. And location is fixed - inside the (roughly) red-outlined wedges. Criteria are a mixture of how much forest wedges already contain and how does it correlate with the dominating wind directions (e.g. dominating winds come from west and west-south but these wedges contain little greenery) and then adding new areas accordingly to get the best benefit. We are running this through a chemistry-meteorological model called HIRMAL. It's one of many scenarios of land-use change so we are keeping it rather simple.

Red outline - green wedges, Green - forest; Pink - Urban, Green-yellow dash - New afforestation

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  • Are you trying to move forest areas while keeping their shape? would you like to maintain the overal forest capacity in your layer constant? You can use a combination of buffer and difference tool to expand existing selected forests to non-urban areas. Might be worth to consider some raster manipulation instead. – dof1985 Apr 20 '15 at 9:44
  • I edited the description. new forest areas shapes are irrelevant. It's the total area that is important and yes, it forest capacity is fixed. I considered buffers and difference tool, but wouldn't it mean playing with it until I 'hit it' and get the acceptable result? – AStysiak Apr 20 '15 at 10:03
  • Playing yes, but due to your edit, I guess buffer is not your tool. It is hard to maintain area of irregular shapes with buffer. See this thread. Can you elaborate on the criteria you plan to decide on the location on new forest and which old should be removed instead? You mentioned wind direction, are there anymore? and how are they going to influence your decision? – dof1985 Apr 20 '15 at 10:20
  • EDIT 2: answers your questions I hope. Thank you for the thread you suggested, but I don't know how would that be any different from playing with buffers and difference tool. – AStysiak Apr 20 '15 at 11:06

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