Forschungszentrum Landschaftsentwicklung und Bergbaulandschaften (FZLB)
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Eine zunehmende Knappheit ackerbaulicher Standorte und der zugleich steigende Bedarf an nachwachsenden Rohstoffen für die energetische und stoffliche Nutzung lösen verstärkt Konflikte zwischen der Nahrungsmittelproduktion und der Biomasseproduktion aus. Marginale Standorte kommen entsprechend immer stärker in den Blickpunkt als mögliche Erweiterungsflächen für die Biomasseproduktion. In der wissenschaftlichen Auseinandersetzung fehlt allerdings eine eindeutige Definition für derartige marginale Standorte. Gerade im Hinblick auf eine mögliche Reduzierung von Nutzungskonflikten ist die Abgrenzung zu stillgelegten, aber agrarisch nutzbaren Standorten oder zu natürlichen Badlands, mit naturschutzfachlichen Potentialen oftmals schwierig. Das EU H2020-Projekt SEEMLA untersucht Potentiale und Verfügbarkeit von marginalen Standorten europaweit. In Deutschland, Griechenland und der Ukraine wurden Pilotstandorte eingerichtet, auf denen der Anbau von Bioenergiepflanzen exemplarisch durchgeführt wird. Für eine erste Bewertung der Standortspotentiale und auch der Ursachen der Marginalität der Standorte wurden Bodenuntersuchungen an allen Pilotstandorten nach den Vorgaben des Muencheberger Soil Quality Rating-Verfahrens (SQR) (1) durchgeführt und die Standorte klassifiziert. Das SQR-Verfahren bewertet ausgewählte Boden- und Standortseigenschaften und bezieht zusätzlich mögliche limitierende Faktoren (Hazard Indicators) wie Versauerung, Versalzung, Vernässung etc. mit ein, um eine Gesamtbewertungszahl zur Bodenfruchtbarkeit zu ermitteln. Dieser Beitrag stellt anhand der SEEMLA-Standorte exemplarisch Böden marginaler Standorte vor. Mit Hilfe der SQR Hazard Indicators werden charakteristische limitierende Faktoren vorgestellt. Es wird zudem versucht, die untersuchten Standorte in eine mögliche Klassifikation marginaler Standorte einzupassen und ihre Eignung für die Biomasseproduktion einzuschätzen.
An artificial catchment was constructed to study initial soil and ecosystem development. Our research site is the hydrologic catchment area “Chicken Creek”, 20 km south of the city Cottbus (Germany), which is left to undirected succession. The approximately 6-ha catchment area was built in 2005 of coarse-textured quaternary sediments and forms a back- and foot-slope that flattens out to a pond. A clay liner, 2-3 m in thickness, seals the catchment at the bottom. The initial “soil” layer consists of sandy quaternary sediments, approximately 2–3 m in thickness, that overlay the clay liner. The sediments of the artificial system are in the very initial stage of soil formation. As a key process, the pore structure dynamics in the soil at the surface strongly influences erosion, infiltration, matter dynamics, and vegetation establishment. Little is known, however, about early macropore formation. This presentation focuses on observations of the general development of the catchment, with emphasis on soil structure modifications, such as soil surface crusts, structure formation from ground beetles, moss vegetation and its effect on water flow.
We visualized the soil structure and flow patterns using a combination of neutron radiography, neutron tomography (NT) and X-ray computed tomography (CT) experiments. All techniques were used to describe preferential pathways as a soil
structure with CT and the process of preferential flow of water with NT. For the first time, neutron radiation was applied on undisturbed soil cores to visualize water distributions in natural soils on three examples containing heterogeneities of different origin. Our observations demonstrate relatively high abiotic and biotic dynamics of soil pore structure in the soil surface even during the very early development stages of the catchment. The structure formation influences runoff and infiltration by forming sealing layers or preferential flow paths, due to biotic activity.
The term “marginal land” refers to generally unfavourable site conditions for traditional economic agriculture or forestry. The definitions of marginality differ widely and also the scientific perspective on this type of land is very heterogeneous. However, with regard to the fast growing competition for arable lands between agricultural food production and the increasing need for growing renewable resources, such marginal lands could offer a mitigation option. Whereas agriculture is concentrating rapidly on the most fertile soils, the production of biomass as the renewable basis for various products could be shifted to sites with lower soil fertility. This in general is the main objective of the H2020 funded EU project SEEMLA (acronym for “Sustainable exploitation of biomass for bioenergy from marginal lands”). This project aims at an establishment of suitable innovative land-use strategies for a sustainable production of plant-based energy on marginal lands, while improving general ecosystem services. This approach will be tested in selected casestudy regions in Europe on marginal lands with different reasons for their marginality. One of the central tasks of this project was the characterization and classification of the investigated marginal sites according to a common definition. For that reason the Muencheberg Soil Quality Rating (SQR) system1 was adapted and applied at sites
in Germany, Greece and Ukraine. This paper gives an overview of the importance and properties of different soil parameters and ecological site conditions for this classification. Even if the occurrence of the single site limitations epends on regional conditions, some generalizations are possible. Based on the respective dominating soil related restrictions, a classification of types of marginality and of marginal lands can be derived also with regard to their land use potentials for renewable resources. Further, cultivating biomass on marginal lands may offer remediation potentials with regard to the described ecological restraints of marginal sites.
Landscapes and ecosystems are complex systems with many feedback mechanisms acting between the various abiotic and biotic components. The knowledge about these interacting processes is mainly derived from mature ecosystems. The initial development of ecosystem complexity may involve state transitions following catastrophic shifts, disturbances or transgression of thresholds. The Chicken Creek catchment was constructed in 2005 to study ecosystem development
of an initial ecosystem at the landscape scale. The world´s largest constructed catchment has a hillslope-shaped 6 ha size with defined boundary conditions and well-documented inner structures1. For 12 years, we have been monitoring the development of different system compartments2,3. The fast formation of patterns and increasing heterogeneity were challenges for the monitoring program. Starting with a regular 20 × 20 m grid in the initially homogeneous system, monitoring installations were continuously complemented by more pattern and patch oriented measurements in order to catch up with both the spatial and temporal dynamics of the catchment. The monitoring program includes both
high-resolution temporal recordings (e.g., groundwater levels, discharge, meteorological data, soil moisture), spatial sampling campaigns (e.g., soil properties) and annual vegetation surveys. In addition, we use drone images to document the site development. The presentation describes the monitoring approach and adaptation with examples from vegetation, soil and hydrological data at different spatial and temporal scales. From the monitoring data we were able to derive different phases during initial development that are characterized by abiotic/biotic feedback mechanisms controlling catchment functioning. Detailed monitoring of the Chicken Creek catchment with known boundary conditions and structure information could help in disentangling general feedback mechanisms between hydrologic, pedogenic, biological and geomorphological processes as well as in gaining a more integrative view of succession and its drivers during the transition from initial, less complex systems to more mature ecosystems. Long-term time series of data are the key for a better understanding of these processes and the effects on ecosystem self-organization and resilience.
The Chicken Creek catchment was constructed in 2005 to study ecosystem development of an initial ecosystem at the landscape scale. The site has an area of 6 ha with defined boundary conditions and known inner structures. Since more than 10 years, we are monitoring the unrestricted development of different system compartments. The fast development, the formation of patterns and increasing heterogeneity were challenges for the monitoring program. Starting with a regular 20 x 20 m grid in the initially homogeneous system, monitoring installations were continuously complemented by more pattern and patch oriented measurements in order to catch up with both the spatial and temporal dynamics of the catchment. The monitoring program includes both high-resolution temporal recordings (e.g. groundwater levels, discharge, meteorological data, soil moisture), spatial sampling campaigns (e.g. soil properties) and annual vegetation
surveys. In addition, we use drone images to document the site development. The presentation describes the monitoring approach and adaptation with examples from vegetation, soil and hydrological data at different spatial and temporal scales.
Marginal lands are often considered as unfertile and not productive. They are widely excluded from modern land use by conventional agriculture. Assessment of soil fertility usually shows very low productivity potentials at least for growing traditional crops. However, it can be frequently observed that natural succession at different types of marginal lands leads to very diverse and nonetheless productive ecosystems. Examples can be found at abandoned former industrial or transportation sites which were set aside and not further maintained – and also in post-mining landscapes. In one of the lignite open cast mines of the State of Brandenburg in Eastern Germany a landscape observatory was
established in 2005 for observing this natural ecosystem development under marginal site conditions. The site of 6 ha is part of the post-mining landscapes of Lusatia which are often characterized by poor soil conditions and clearly reduced soil fertility. It is named “Hühnerwasser-Quellgebiet” (Chicken Creek Catchment) after a small stream that is restored again after destruction by the mining operations. It is planned to serve as the headwater of this stream and was left to an unrestricted primary succession. A comprehensive scientific monitoring program is carried out since the start of ecosystem development in 2005. The results offer exemplary insights into the establishment of interaction networks between the developing ecosystem compartments. After 10 years a large biodiversity, expressed by a high number of species, can be found at this site as the result of natural recovery processes. A large number of both tree species and individuals have settled here. Even if no economic use of the site and of the woody biomass produced by these trees is planned, an overall assessment of the biomass production was carried out. The results showed that the biomass production from natural succession without any application of fertilizers etc. is directly comparable with yields from adjacent post-mining sites where trees are grown in agroforestry systems for bioenergy production. This reflects the general potentials of marginal lands with regard to biomass production.
One of the main issues that the forest sector is facing is to achieve a balance between the demand for biomass &wood production and the need to preserve the sustainability and biodiversity of forest ecosystems. The purposes of the new approaches are to ensure more efficient management of ecosystems and implement intensive forestry that will increase biomass production & timber yields. To achieve this, we need to determine the macroeconomic potential of the various options available, including the use of biotechnology and genetics. The success of the forests plantations capacity may be solved through forest certification, based on: a) Stabilization of the forests and soils structure. b) Hierarchy of biomass production in the forest’s management process. c) rganization and implementation of effective plantation on marginal lands. d) Maintenance or increase of forest productivity by introducing new items as and when they are required. It is important to evaluate of the influence of factors such as the quality of soils of plantation areas, the utilization of the genetic resources and the management of forest operations with the environmental economic criteria such as net present value of benefits (NPV) and the corresponding flow annuities (EACF).The existing evaluations studies showed that the quality of the plantation areas has the most influence and through validated quality seed production can generate an increase in the NPV up to 73%. The importance of seedlings quality in timber and bio-energy production on marginal lands based on the literature it is estimated according to the heredity of the characteristics of the wood structure (except shrinkage). This clearly indicate that seedlings with the appropriate morphological characteristics can significantly improve the growth performance and help to support the development of biomass plantations oriented in tailor-made timber and bio-energy production.
An ever growing demand for energy and the widely proposed switch from fossil fuels to more sustainable energy sources puts the cultivation and use of bioenergy plants into focus. However, bioenergy production on regular and fertile agricultural soils might conflict with the worldwide growing demand for food. To mitigate or omit this potential conflict, the use of low quality or marginal land for cultivation of bioenergy plants becomes favorable. Against this background the definition and assessment of land marginality and, respectively, the evaluation whether and to which extent specific areas are marginal and thus convenient for sustainable bioenergy production, becomes highly relevant. Within the framework of the EU funded Horizon 2020 project SEEMLA, we attempted to asses land marginality of designated test sites in the Ukraine, Greece and Germany by direct field survey. For that purpose, soil and site properties were investigated and evaluated by applying the Muencheberg Soil Quality Rating (SQR) method, developed at the Leibniz Centre for Agricultural Landscape Research (ZALF). The method deploys a comprehensive set of biogeophysical and chemical indicators to describe and finally evaluate the quality of the soil and site by a score ranging from 1 to 100 points. Field survey data were supported by additional laboratory tests on a representative set of soil samples. Practical field work and analysis of field and lab data from the investigated sites proved the applicability of the SQR method within the SEEMLA context. The SQR indices calculated from the field and lab data ranged from 2 to < 40 and clearly demonstrated the marginality of the investigated sites in the Ukraine, Greece and Germany, which differed considerably in respect to their characteristics. Correlating the site quality index to yield data reflecting yield estimations for common bioenergy plants such as willow (Salix sp.), black locust (Robinia pseudoacacia) and poplar (Populus sp.) cultivated at the respective test sites, revealed that SQR might additionally reflect the potential yield of the investigated sites.