Let's stay realistic!
Lets simply suppose we had answered the previous questions in a satisfactory way and had decided in favor of the continuing existence of mankind in a dignified way. Then future landscape planning would be the ever lasting quest of an approach halfway in-between the extremes of too strict conventionalism and too abrupt changes.
Let's consider in our work at least the most important changes of the last few years!
The conditions of human existence for example have changed dramatically. Already today or at least in the immediate future more than half of all job positions in developed countries will be situated in the communication and information sectors (see the following picture). (figure 1)
This means that living and working can take place in a different form and in other locations than before. One main reason for the developing of megapolis in former times, the possibility of communicating with others, becomes more and more independent of where you live. So the best times of big cities should be over.
That also calls into question many basic ideas behind the existing Regional Planning Laws (Raumordnungsgesetzgebung), e.g. the so called "Zentrale-Ort-Prinzip" (urban center axiom).
More than half of all jobs could be located in rural areas. If we consider a rather conservative, protectionist vision, we could for example build work- and living places from recyclable materials and put them underground to preserve existing vegetation, like it is the case with the tent- and hill houses, shown below. (Picture 2) (figure 2)
Or we could revive vegetation at the top of our house, like it is the case with the house shown below, which I called "raised slope". (Picture 3) (figure 3).
But we could also locate our live- and working places up in the sky, so that vegetation does not get hurt. (Picture 4) (figure 4).
By this way, many undesirable effects of urbanization could be avoided a priori.
But we may also be more optimistic/brave! It has been shown for example, that this forest of the prince of Oettingen-Spielberg (picture 5) (figure 5), after 500 years of growing spruces shows no single sign of irreversible soil pollution.
These picture from lake "Altmühlsee" (picture 6) (figure 6)demonstrate that also large-area grassland can be redesigned into an attractive lake area during a short interval of only ten years. A third of the area has been set aside to build a partially soggy island for birds, that , after only a few years, has been designated a nature reserve due to the large number of birds living in this place.
As a last example picture, I will show you the regional recultivation of former coal-mines to the south of the German city of Leipzig (picture 7). (figure 7). According to my design, we would establish so called "eco-residences" within a large-area biotope. The most attractive real estates on shore should not be sold, but its owners will be obliged to design and cultivate area 10 sizes as big as the houses area according to the wishes of environmental experts!
In this way, after about 50-70 years a paradise should have been created - for plants, animals and humans!
Maybe by this time it will even already be possible due to genetic engineering to let plants or new life forms build our houses, as shown on the collage below (picture 8). (figure 8).