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Protection of Soils through Environmental Integration

Protection of Soils through Environmental Integration


Konstantin Terytze, Ines Vogel


Free University of Berlin, Department of Geosciences, Working Group Geoecology



Soil was the last medium to be protected in Germany after water and air with the Federal Soil Protection Act of 1998 and its Federal Soil Protection and Contaminated Sites Ordinance (BBodSchV) of July 12th, 1999.

According to the German Federal Soil Protection Act the natural function of soil as a habitat for human beings, animals, plants and soil organisms as well as the production function is among others to be protected by deriving soil values for dangerous chemicals/contaminants regarding their amounts in the environment, their persistence and/or their toxicity.

The Federal Soil Protection Act integrates the preventive/precautionary soil protection and the remediation of contaminated sites. The basic idea is the protection from harmful changes to the soil. Precautionary values, trigger and action values as laid down in the law are an important instrument to realise its requirements regarding to good soil quality with regard also to bioavailability.

The requirements of precautionary soil protection mark the basis for other legislation regulating different impacts on soil like fertilizing regulation, biowaste and sludge application regulation.

Soil has to integrate the requirements of a wide range of branches like agriculture, production of renewable resources for the production of materials and energy, waste management, groundwater protection, nature conservation and climate protection. The key to fulfil all this tasks lies in the improvement of soil functions especially regarding to soil fertility and the organic substance/matter of soil.

A new way for integrating all these requirements is the application of biochar substrates to soil aiming in improvement of natural soil functions like capacity for the storage of nutrients and water and revival of soil biological life as well as the enlargement of fertilizing efficiency, higher quality and quantity of harvest success, healthier soil flora and fauna, enlargement of decomposition of organic pollutants and climate protection via long-term carbon sequestration – all this embattled in regional material cycles.

Two research projects dealing with this topic are presented: LaTerra and TerraBoGa.

In the TerraBoGa project “Closed material cycles by material flow management by using the Terra-Preta-Technology in the Botanic Garden Berlin in terms of resource efficiency and climate protection” are considered.

The main focus of this project is the efficient utilization of biogenic waste and residual materials like green waste and faeces of employees and visitors. The research and development project intends to complete the internal, small scale material cycles in the Botanic Garden Berlin. The aim is to make a contribution to sustainable soil management within Urban Farming in terms of carbon reduction and the impacts of climate change processes.

The Berlin Botanic Garden produces around 1500 m³ of green waste, pruning waste, grass cuttings and wood. Much of this is still unused and is disposed of in a way that is both energy and cost intensive, as well as the sewage from employees and the annual 260.000 visitors of the Botanic Garden Berlin. In contrast, around 350 m³ of compost and fertilizer has had to be bought in each year.

The total biomass is planned to be turned into nutrient-rich black earth (premium potting soil) by using the “Terra Preta-Technology”. In contrast to conventional composting methods the Terra Preta-Technology is based on lactic acid fermentation by using biochar. Due to the high stability the biochar is an important element to provide a long-term storage for nutrients and water for plants.

The environmental relief potential of the closed material cycle and the plant growth effectiveness of TPS will be determined by tests in laboratories and field studies taking into account chemical and physical as well as biological parameters.

The interdisciplinary and transdisciplinary joint research project “Sustainable land-use by regional energy and material flow management using “Terra-Preta-Technology” on military conversion areas and low-yield-locations (LaTerra)” seeks innovative system solutions for resource efficiency, climate protection and area revaluation by means of an integrative approach. The project’s fundament is set by implementing the zero-emission-strategy, launching a regional resource efficient material flow management as well as utilising “Terra-Preta-Technology” as an innovative system component.

As the centrepiece of optimised regional biogenic material flows Terra Preta Substrate (TPS) shall be utilised exemplarily in model regions.

In regional project 1 (state of Brandenburg, county Teltow-Fläming) TPS shall be used on military conversion areas, which are contaminated with polycyclic aromatic hydrocarbons and mineral oil hydrocarbons. It will be examined, whether the use of TPS causes accelerated pollutant reduction and whether this area is available for renewable raw material production.

In regional project 2 (Western Lusatia, county Oberspreewald-Lusatia) reclamation and renaturation of post-mining-landscapes is first priority. In this case, the project seeks for an upgrade of devastated soils for plant production as well as for restoration of soil functions and setup of organic soil substances.

In regional project 3 (state of North Rhine-Westphalia, city of Schmallenberg) reforestations of large scale windbreakage areas shall be supported by using TPS. Soil stabilisation, increased growth and survival of young trees and decreased nutrient losses are desired achievements.

The crop production effectiveness and environmental compatibility of TPS will be determined by tests in laboratories, by lysimeter and open land taking into account chemical and physical as well as biological parameters.