TY - CHAP A1 - Medinski, Tanya V. A1 - Freese, Dirk A1 - Böhm, Christian ED - Palma, Joao H. N. T1 - Soil respiration in alley-cropping system composed of black locust and poplar trees, Germany T2 - 2nd European Agroforestry Conference: Integrating Science and Policy to Promote Agroforestry in Practice, June 2014, Cottbus, Germany N2 - Understanding of soil carbon dynamics after establishment of alley-cropping systems is crucial for mitigation of greenhouse gas CO2. This study investigates soil CO2 flux in an alley-cropping system composed of black locust (Robinia pseudoacacia L.) and poplar (Max 1) tree strips and adjacent to them crop strips (Lupinus/ Solarigol). Soil CO2 flux was measured monthly over the March – November 2012 period, using a LI-COR LI-8100A automated device. Simultaneously with CO2 flux measurements, soil and air temperature, soil moisture, microbial C and hot water-extractable carbon (HWC) were determined for soils collected nearby each measurement collar. Root biomass was measured to a depth of 15 cm. In all sampling areas, soil CO2 flux increased from May to July, showing a significant positive correlation with air and soil temperature, which can be a reflection of increase in photosynthetic activity over the warm summer months. The relationships between soil moisture and CO2 flux showed positive correlation only for the warm period (May - October), indicating enhancing role of soil moisture on microbial mineralization and root respiration. CO2 flux values varied between sampling areas at different vegetation periods, with significantly higher values in trees over the summer. This could be attributed to the higher photosynthetic activity and higher root density in trees coppices compared to crops. In autumn, after seeding catch crop mix Solarigol, CO2 flux was significantly higher in crops compared to trees, which could be related to soil tillage prior to seeding of crops, as well as to the higher photosynthetic activity of newly seeded crops at the period of rapid plant growth. Despite a seasonal variation in CO2 flux between sampling areas, aaverage CO2 flux values observed over March – November period did not differ significantly between sampling areas, showing 2.5, 3.2, and 2.9 μmol m-2 s-1 values for black locust, poplar and crops, respectively. A greater C loss with soil respiration under trees in summer period may be compensated by greater C assimilation and storage in woody biomass, and the greater respiration from crop strips after tillage in autumn. Y1 - 2014 UR - http://www.repository.utl.pt/handle/10400.5/6764 SN - 978-972-97874-4-7 SP - 253 EP - 254 ER - TY - CHAP A1 - Gerwin, Werner A1 - Schaaf, Wolfgang A1 - Hinz, Christoph A1 - Hüttl, Reinhard F. T1 - Monitoring of Ecosystem Development at the Constructed Catchment Chicken Creek T2 - TERENO International Conference 2014, From Observation to Prediction in Terrestrial Systems, 29 September to 2 October 2014, Book of Abstracts N2 - The constructed catchment Chicken Creek was established in 2005 as an experimental landscape laboratory for ecosystem research. The 6 ha area with clearly defined horizontal as well as vertical boundary conditions was left for an unrestricted primary succession. The developing ecosystem offers the opportunity to study most processes occurring at the interface of bio-, pedo-, geo- and hydrosphere. Particularly interactions and feedbacks between different evolving compartments as well as the establishment of ecosystem functions and services can be investigated during the ongoing ecosystem development. The catchment is extensively instrumented since 2005 in order to detect transition stages of the ecosystem. Comprehensive data recorded with a high spatial and temporal resolution include hydrological, geomorphological, pedological, limnological as well as biological parameters. This site offers the unique situation of an early stage ecosystem with highly dynamic system properties. The first years of development were characterized by a fast formation of geomorphological structures due to massive erosion processes at the initially non-vegetated surface. Hydrological processes led to the establishment of a local groundwater body within 5 years. In the following years the influence of biological structures like vegetation patterns gained an increasing importance. Feedbacks between developing vegetation and e.g. hydrological features became more and more dominant. As a result, different phases of ecosystem development could be distinguished until now. This observatory offers manifold possibilities to identify and disentangle complex interactions between ecosystem compartments in situ under natural conditions. The originally low complexity of the system is growing with time facilitating the identification of influences of newly developing structures on ecosystem functions. Thus, it is possible to study effects of small-scale processes on the whole system at the landscape scale. In addition, the highly dynamic initial system properties allow the observation of multifaceted changes of ecosystem properties and functions within short periods of time. Y1 - 2014 UR - http://www.tereno-conference2014.de/tereno-conference/EN/download_book_of_abstracts/_node.html SP - P2-12 ER - TY - CHAP A1 - Böhm, Christian A1 - Kanzler, Michael A1 - Freese, Dirk ED - Palma, Joao H. N. T1 - Impact of black locust hedgerows on wind velocity and wind erosion in Eastern Germany T2 - 2nd European Agroforestry Conference: Integrating Science and Policy to Promote Agroforestry in Practice, June 2014, Cottbus, Germany N2 - The production of energy wood on arable land increased in Germany during the last years. Black locust (Robinia pseudoacacia L.) is a suitable tree species in order to ensure substantial woody biomass yields on agricultural sites in eastern Germany. Arranged in hedge structures (alley cropping) positive effects on wind velocity and hence on soil erosion can be expected for the whole agricultural production area. Results of field measurements carried out in several alley cropping sites located in eastern Germany show that wind velocity can be reduced by more than 50 %, even though tree hedgerows were not higher than four meters. Here, the reduction of wind speed was dependent on the distance to woody crops, the width of the crop alleys and the orientation of hedgerows. As a result of wind speeds reduction the potential of soil erosion by wind decreases considerably. The risk of wind erosion is even nearly negligible for 24 m wide or smaller crop alleys. The establishment of short rotation hedgerows could contribute to an enhanced protection against wind erosion and thus to an ecological and possible long-term economic appreciation of agricultural sites. Aside from erosion control, further advantages such as a lower evaporation rate, and thus a crop yield increase, may be connected to the establishment of such agroforestry systems. Against the background of the increasing demand for woody biomass for bioenergy, the cultivation of fast growing trees on agricultural sites can furthermore result in an additional incomefor farmers. This is a prerequisite for the spread of this kind of agroforestry in Germany, because a comparable large share of an unprotected field has to be planted with trees in order to ensure an efficient windbreak. Y1 - 2014 UR - http://www.repository.utl.pt/handle/10400.5/6764 SN - 978-972-97874-4-7 SP - 267 EP - 268 ER - TY - CHAP A1 - Quinkenstein, Ansgar A1 - Jochheim, Hubert ED - Palma, Joao H. N. T1 - Model-based analysis of the carbon sequestration potential of short rotation coppices on reclaimes lignite mine sites T2 - 2nd European Agroforestry Conference: Integrating Science and Policy to Promote Agroforestry in Practice, June 2014, Cottbus, Germany N2 - In Central Europe, short rotation coppice systems for the production of woody biomass come increasingly into focus as these wood plantations offer an opportunity to sustainably produce biomass for energy production and to sequester substantial amounts of CO2 within the plantations and the soils at the same time. In this study, a modeling analysis of the C cycle of a poplar (Populus suaveolens Fisch. x Populus trichocarpa Torr. et Gray cv Androscoggin) and a black locust (Robinia pseudoacacia L.) SRC is presented. The calculations were performed with the bookkeeping C-model shortcar. The calculated estimates of C accumulation within the biomass, the litter layer, and the soil were validated against field data and published results from a selection of scientific studies. For the SRC on reclaimed mine sites a high C sequestration potential was found which amounted in the reference scenario over a period of 36 years to an accumulated net biome production of about 65 Mg C ha-1 for R. pseudoacacia and about 9 Mg C ha-1 for poplar, while the latter clearly suffered from the harsh growth conditions at the reclamation sites. Summarizing, the results suggested a high potential of SRC for C sequestration and C emission mitigation, especially on marginal sites. Y1 - 2014 UR - http://www.repository.utl.pt/handle/10400.5/6764 SN - 978-972-97874-4-7 SP - 253 ER - TY - CHAP A1 - Elmer, Michael A1 - Schaaf, Wolfgang A1 - Gerwin, Werner A1 - Hinz, Christoph T1 - The constructed catchment ’Chicken Creek’ – a landscape observatory to analyze processes and feedback mechanisms during initial ecosystem development T2 - European Geosciences Union, General Assembly 2014, Vienna, Austria, 27 April – 02 May 2014 N2 - We investigated the initial development of the landscape observatory ’Chicken Creek’, Germany, an artificial catchment with well known boundary conditions and inner structures (Gerwin et al., 2011). Over a period of nine years, we observed considerable changes within the site (Elmer et al., 2013). Both internal and external factors could be identified as driving forces for the formation of structures and patterns in the catchment. Over time, secondary structures and patterns evolved and became more and more important. Invading biota and vegetation succession initialized feedback mechanisms resulting in pattern and habitat formation as well as in increased differentiation, heterogeneity and complexity that are typical characteristics of ecosystems (Schaaf et al., 2013). The processes and feedback mechanisms in the initial development of a new landscape may deviate in rates, intensity, and dominance from those known from mature ecosystems. It is therefore crucial to understand these early phases of ecosystem development and to disentangle the increasingly complex interactions between the evolving terrestrial and aquatic, biotic, and abiotic compartments of the system. Y1 - 2014 UR - http://meetingorganizer.copernicus.org/EGU2014/EGU2014-6042.pdf N1 - EGU2014-6042-1 PB - European Geophysical Society CY - Katlenburg-Lindau ER - TY - CHAP A1 - Hinz, Christoph A1 - Schaaf, Wolfgang A1 - Gerwin, Werner T1 - Competing feedbacks drive state transitions during initial catchment evolution: Examples from post-mining landscape and ecosystems evolution T2 - European Geosciences Union, General Assembly 2014, Vienna, Austria, 27 April – 02 May 2014 N2 - Within the context of severely disturbed landscapes with little or no ecological memory, such as post-mining landscapes, we propose a simple framework that explains the catchment evolution as a result of competing feedbacks influenced by the initial conditions and the atmospheric drivers such as rainfall intermittency and intensity. The first stage of the evolution is dominated by abiotic feedbacks triggered by rainfall and subsequent fluid flow causing particle mobilisation on the surface and in the subsurface leading to flow concentration or in some instances to densification of surface and subsurface substrates. Subsequently, abiotic-biotic feedbacks start to compete in the sense that biological activity generally stabilizes substrate by preventing particle mobilisation and hence contribute to converting the substrate to a habitat. We suggest that these competing feedbacks may generate alternative stable states in particular under semi-arid and arid climatic conditions, while in temperate often energy limited environments biological process “outcompete” abiotic processes leading to a stable state, in particular from the water balance point of view for comparable geomorphic situations. Y1 - 2014 UR - http://meetingorganizer.copernicus.org/EGU2014/EGU2014-12609.pdf N1 - EGU2014-12609 PB - European Geophysical Society CY - Katlenburg-Lindau ER - TY - CHAP A1 - Gerwin, Werner A1 - Schaaf, Wolfgang A1 - Elmer, Michael A1 - Hinz, Christoph T1 - The constructed catchment Chicken Creek as Critical Zone Observatory under transition T2 - European Geosciences Union, General Assembly 2014, Vienna, Austria, 27 April – 02 May 2014 N2 - The constructed catchment Chicken Creek was established in 2005 as an experimental landscape laboratory for ecosystem research. The 6 ha area with clearly defined horizontal as well as vertical boundary conditions was left for an unrestricted primary succession. All Critical Zone elements are represented at this site, which allows the study of most processes occurring at the interface of bio-, pedo-, geo- and hydrosphere. It provides outstanding opportunities for investigating interactions and feedbacks between different evolving compartments during ecosystem development. The catchment is extensively instrumented since 2005 in order to detect transition stages of the ecosystem. Data recorded with a high spatial and temporal resolution include ydrological, geomorphological, pedological, limnological as well as biological parameters. Y1 - 2014 UR - http://meetingorganizer.copernicus.org/EGU2014/EGU2014-6248.pdf N1 - EGU2014-6248 PB - European Geophysical Society CY - Katlenburg-Lindau ER - TY - CHAP A1 - Kanzler, Michael A1 - Böhm, Christian A1 - Freese, Dirk ED - Pekrun, C. ED - Wachendorf, Magnus ED - Francke-Weltmann, L. T1 - Nährstoffgehalte und Erträge von Kartoffeln in Abhängigkeit zur Entfernung vom Gehölzstreifen in einem Agroforstsystem T2 - Tagung der Gesellschaft für Pflanzenbauwissenschaften e.V. mit der Max-Eyth-Gesellschaft Agrartechnik VDI-MEG, 16.-18. September 2014, Wien, Technik in der Pflanzenproduktion N2 - Die Agroforstwirtschaft, also die kombinierte Nutzung von Bäumen und Feldfrüchten auf einer landwirtschaftlichen Fläche, gewinnt vor dem Hintergrund der steigenden Holznachfrage sowie diverser ökologischer Vorteilswirkungen auch in Deutschland zunehmend an Bedeutung. Verglichen mit den bereits bekannten Umweltleistungen, wie etwa einer erhöhten Biodiversität sowie dem Schutz vor Winderosion, ist der potenzielle Einfluss der Gehölzstreifen auf das Wachstum bzw. die Nährstoffversorgung von angrenzenden Feldfrüchten in Agroforstsystemen noch weitestgehend ungeklärt. Zur Quantifizierung dieser möglichen Interaktion wurden im Jahr 2013 auf einem etwa 40 ha großen Agroforst-Versuchsstandort nahe der Stadt Forst (Lausitz) umfangreiche Nährstoff- und Ertragsuntersuchungen durchgeführt. Y1 - 2014 SP - 264 EP - 265 PB - Verlag Halm CY - Göttingen ER - TY - CHAP A1 - Böhm, Christian A1 - Kanzler, Michael A1 - Freese, Dirk ED - Pekrun, C. ED - Wachendorf, Magnus ED - Francke-Weltmann, L. T1 - Auswirkungen agroforstlicher Kurzumtriebswirtschaft auf das Bodenerosionspotential und den Kohlenstoffhaushalt sudbrandenburgischer Ackerstandorte T2 - Tagung der Gesellschaft für Pflanzenbauwissenschaften e.V. mit der Max-Eyth-Gesellschaft Agrartechnik VDI-MEG, 16.-18. September 2014, Wien, Technik in der Pflanzenproduktion N2 - ln der Region Südbrandenburg herrschen ertragsschwache, sandige Böden vor, die von Natur aus ein geringes Wasserhaltevermögen und ein hohes Degradationspotential durch Winderosion aufweisen. Zudem existiert hier ein vergleichsweise großer Flächenanteil an strukturarmen, großflächigen Bergbaufolgelandschaften, die sich zume1st durch eine geringe Standortsgüte auszeichnen. In diesem Beitrag werden Ergebnisse aus versChiedenen Studien vorgestellt, in denen untersucht wurde, ob und in welchem Ausmaß durch im Kurzumtrieb bewirtschaftete Agroforstsysteme die Anfälligkeit dieser Ackerstandorte gegenüber Winderosion gemindert und die im Boden bzw. Kippensubstrat vorhandene Menge an organischer Substanz erhöht werden kann. Y1 - 2014 SP - 54 EP - 55 PB - Verlag Halm CY - Göttingen ER - TY - CHAP A1 - Spröte, Roland A1 - Veste, Maik A1 - Fischer, Thomas A1 - Raab, Thomas A1 - Bens, Oliver A1 - Hüttl, Reinhard F. T1 - Development of biological soil crusts and their influence on soil hydrology in the recultivation area of lignite open-cast mining district in Lower Lusatia (Germany) T2 - EGU General Assembly 2012, held 22-27 April, 2012 in Vienna Y1 - 2012 N1 - EGU2012-6372 PB - European Geophysical Society CY - Katlenburg-Lindau ER -