Abstract

The global urban landscape takes about 3% of the continental surface and emits almost 80% of anthropogenic CO2 emissions. Therefore the ecosystem „City“ plays a role as „creator“ in the discussion about sources and sinks of greenhouse gases and also from the perspective of mitigation and adaptation regarding the courses and consequences of the climate change. On the municipal level concepts for climate protection focus particularly the reduction of the annually emission of CO2. Until now the natural storage capacity of the urban CO2 sinks “soil” and “vegetation” is considered hardly in the science and however less in the (planning) practice. To extend the state of research and to educe some recommendations for a climate-compatible urban development this study analyses the CO2 storage effect of the integrated concept for climate protection from the “Waldstadt- Silberhöhe” in Halle (Saale), Saxony Anhalt, Germany - more precisely: the afforestation numerous demolition sites. Based on the allometric regression between “diameter at breast high” and “above-ground woody biomass”, a storage capacity about 4,866 Mg CO2 of the current tree population in the “Waldstadt- Silberhöhe” was determined with biomass equations from differ ent forestry studies. By 2025, the CO2 absorption will increase about 14,150 Mg CO2 due to the secondary growth of the trees. In this context it is important that the share of planted areas in shrinking cities will rise because of the demolition of vacancies. This promises an increasing CO2 storage. To optimize this potential during future tree plantations three scenarios were modeled. They differ in the parameters “tree density” as well as the tree characteristics “bulk density” and “growth rate”. From their comparison can be derived different recommendations for implementation and these entail advanced positive effects for other ecosystem services.