@article{LischeidKalettkaMerzetal.2016,
  author    = {Lischeid, Gunnar and Kalettka, Thomas and Merz, Christoph and Steidl, J{\"o}rg},
  title     = {Monitoring the phase space of ecosystems: Concept and examples from the Quillow catchment, Uckermark},
  series = {Ecological indicators : integrating monitoring, assessment and management},
  volume    = {65},
  journal   = {Ecological indicators : integrating monitoring, assessment and management},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1470-160X},
  doi       = {10.1016/j.ecolind.2015.10.067},
  pages     = {55 -- 65},
  year      = {2016},
  abstract  = {Ecosystem research benefits enormously from the fact that comprehensive data sets of high quality, and covering long time periods are now increasingly more available. However, facing apparently complex interdependencies between numerous ecosystem components, there is urgent need rethinking our approaches in ecosystem research and applying new tools of data analysis. The concept presented in this paper is based on two pillars. Firstly, it postulates that ecosystems are multiple feedback systems and thus are highly constrained. Consequently, the effective dimensionality of multivariate ecosystem data sets is expected to be rather low compared to the number of observables. Secondly, it assumes that ecosystems are characterized by continuity in time and space as well as between entities which are often treated as distinct units. Implementing this concept in ecosystem research requires new tools for analysing large multivariate data sets. This study presents some of them, which were applied to a comprehensive water quality data set from a long-term monitoring program in Northeast Germany in the Uckermark region, one of the LTER-D (Long Term Ecological Research network, Germany) sites. Short-term variability of the kettle hole water samples differed substantially from that of the stream water samples, suggesting different processes generating the dynamics in these two types of water bodies. However, again, this seemed to be due to differing intensities of single processes rather than to completely different processes. We feel that research aiming at elucidating apparently complex interactions in ecosystems could make much more efficient use from now available large monitoring data sets by implementing the suggested concept and using corresponding innovative tools of system analysis. (C) 2015 Elsevier Ltd. All rights reserved.},
  language  = {en}
}
@article{KarpTallisSachseetal.2015,
  author    = {Karp, Daniel S. and Tallis, Heather and Sachse, Rene and Halpern, Ben and Thonicke, Kirsten and Cramer, Wolfgang and Mooney, Harold and Polasky, Stephen and Tietjen, Britta and Waha, Katharina and Walt, Ariane and Wolny, Stacie},
  title     = {National indicators for observing ecosystem service change},
  series = {Global environmental change : human and policy dimensions},
  volume    = {35},
  journal   = {Global environmental change : human and policy dimensions},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {0959-3780},
  doi       = {10.1016/j.gloenvcha.2015.07.014},
  pages     = {12 -- 21},
  year      = {2015},
  abstract  = {Earth's life-support systems are in rapid decline, yet we have few metrics or indicators with which to track these changes. The world's governments are calling for biodiversity and ecosystem-service monitoring to guide and evaluate international conservation policy as well as to incorporate natural capital into their national accounts. The Group on Earth Observations Biodiversity Observation Network (GEO BON) has been tasked with setting up this monitoring system. Here we explore the immediate feasibility of creating a global ecosystem-service monitoring platform under the GEO BON framework through combining data from national statistics, global vegetation models, and production function models. We found that nine ecosystem services could be annually reported at a national scale in the short term: carbon sequestration, water supply for hydropower, and non-fisheries marine products, crop, livestock, game meat, fisheries, mariculture, and timber production. Reported changes in service delivery over time reflected ecological shocks (e.g., droughts and disease outbreaks), highlighting the immediate utility of this monitoring system. Our work also identified three opportunities for creating a more comprehensive monitoring system. First, investing in input data for ecological process models (e.g., global land-use maps) would allow many more regulating services to be monitored. Currently, only 1 of 9 services that can be reported is a regulating service. Second, household surveys and censuses could help evaluate how nature affects people and provides non-monetary benefits. Finally, to forecast the sustainability of service delivery, research efforts could focus on calculating the total remaining biophysical stocks of provisioning services. Regardless, we demonstrated that a preliminary ecosystem-service monitoring platform is immediately feasible. With sufficient international investment, the platform could evolve further into a much-needed system to track changes in our planet's life-support systems. (C) 2015 Elsevier Ltd. All rights reserved.},
  language  = {en}
}
@article{LischeidKalettka2012,
  author    = {Lischeid, Gunnar and Kalettka, Thomas},
  title     = {Grasping the heterogeneity of kettle hole water quality in Northeast Germany},
  series = {Hydrobiologia : acta hydrobiologica, hydrographica, limnologica et protistologica},
  volume    = {689},
  journal   = {Hydrobiologia : acta hydrobiologica, hydrographica, limnologica et protistologica},
  number    = {1},
  publisher = {Springer},
  address   = {Dordrecht},
  issn      = {0018-8158},
  doi       = {10.1007/s10750-011-0764-7},
  pages     = {63 -- 77},
  year      = {2012},
  abstract  = {In the young moraine landscape in Northeast Germany, small glacially created ponds, the so-called kettle holes, are very abundant. They exhibit large spatial heterogeneity, seemingly rendering each kettle hole unique. However, this would not be consistent with any scientific approach. Thus, a classification scheme has been developed for kettle holes in Northeast Germany based on morphology, hydrodynamics and connection to stream networks of the kettle holes as well as size, topography and land use of the respective catchment. These indices are assumed to be related both to water quality as well as to biological issues of the kettle holes. Starting in the mid-1990s, an extensive monitoring program has been established in the federal state of Brandenburg, Germany. In this study, a subset comprising 1,316 samples from 79 kettle holes was analysed, where 21 parameters had been determined. Sampling intervals varied widely, and were between bi-weekly and three-monthly at most sites. A nonlinear principal component analysis was performed. The first four components explained 90\% of the variance. These components seem to provide quantitative measures of phosphorus release from the sediments during hypoxic periods, agricultural solute input, algae primary production, and geogenic compounds. This allowed differentiating between the natural and anthropogenic impact factors on water quality. In addition, scores of single components were related to properties of the kettle holes and their environments. The results contribute to a better understanding of biological and biogeochemical processes and can be used to verify the effects of conservation and management strategies for kettle holes.},
  language  = {en}
}