TY - GEN A1 - Zaplata, Markus Klemens A1 - Winter, Susanne A1 - Biemelt, Detlef A1 - Fischer, Anton T1 - Immediate shift towards source dynamics: The pioneer species Conyza canadensis in an initial ecosystem T2 - Flora - Morphology, Distribution, Functional Ecology of Plants N2 - The aim of this study was to detect a potential temporal shift from sink to source dynamics of pioneer plants during primary succession. The study was done in an initial ecosystem, namely an artificially constructed catchment on Pleistocene sands in eastern Germany. The import and export of seeds (including soil seed bank and seed rain), the development of vegetation cover and the population size of all pioneer species were recorded in 2005–2009. The interplay between the spatial distribution of seed rain and the prevailing wind direction provide evidence that seeds of Conyza canadensis (Asteraceae) first and to a considerable amount left the developing ecosystem. A change from a sink to source dynamics was detected already in the first year of both the existence of the site and occurrence of C. canadensis individuals within the site. Population patterns at the landscape unit scale demonstrated extensive auto-correlations in the coverage of this invasive plant at first. Our results underline the pioneer traits of C. canadensis as a prolific seeder and excellent wind disperser, which enables this species to become rapidly dominant over relatively large areas. KW - colonization potential Y1 - 2011 U6 - https://doi.org/10.1016/j.flora.2011.07.001 VL - 206 IS - 11 SP - 928 EP - 934 ER - TY - GEN A1 - Zaplata, Markus Klemens A1 - Winter, Susanne A1 - Fischer, Anton A1 - Kollmann, Johannes A1 - Ulrich, Werner T1 - Species-driven phases and increasing structure in early-successional plant communities T2 - The American Naturalist N2 - Successional phases describe changes in ecological communities that proceed in steps rather than continuously. Despite their importance for the understanding of ecosystem development, there still exists no reliable definition of phases and no quantitative measure of phase transitions. In order to obtain these data, we investigated primary succession in an artificial catchment (6 ha) in eastern Germany over a period of 6 years. The data set consists of records of plant species and their cover values, and initial substrate properties, both from plots in a regular grid (20 m × 20 m) suitable for spatial data analysis. Community assembly was studied by analyses of species co-occurrence and nestedness. Additionally, we correlated lognormal and log series distributions of species abundance to each community. We here introduce a new general method for detection of successional phases based on the degree of transient spatial homogeneity in the study system. Spatially coherent vegetation patterns revealed non-overlapping partitions within this sequence of primary succession and were characterized as two distinct ecological phases. Patterns of species co-occurrence were increasingly less random, and hence the importance of demographic stochasticity and neutral community assembly decreased during the study period. Our findings highlight the spatial dimension of successional phases and quantify the degree of change between these steps. They are an element for advancing a more reliable terminology of ecological successions. KW - spatial analysis Y1 - 2013 U6 - https://doi.org/10.1086/668571 VL - Vol. 181 IS - 1 SP - E17 EP - E27 ER - TY - CHAP A1 - Schaaf, Wolfgang A1 - Biemelt, Detlef A1 - Fischer, Anton A1 - Gerwin, Werner T1 - Chicken Creek after five years: what changed? T2 - EGU General Assembly 2011, Vienna, Austria, 03 – 08 April 2011 Y1 - 2011 UR - http://meetingorganizer.copernicus.org/EGU2011/EGU2011-5755.pdf N1 - EGU2011-5755 ER - TY - GEN A1 - Schaaf, Wolfgang A1 - Elmer, Michael A1 - Fischer, Anton A1 - Gerwin, Werner A1 - Nenov, Rossen A1 - Pretzsch, Hans A1 - Zaplata, Markus Klemens T1 - Feedbacks between vegetation, surface structures and hydrology during initial development of the artificial catchment 'Chicken Creek' T2 - Procedia Environmental Sciences N2 - Our investigations at the artificial catchment ´Chicken Creek´ in Lusatia/Germany aim to disentangle and understand the feedback mechanisms and interrelationships of processes and their co-development with spatial and temporal structures and patterns by studying this initial, probably less complex ecosystem. Intensive measurements were carried out in the catchment with regard to the development of surface structures, hydrological patterns, and vegetation dynamics. During the first seven years, considerable changes within the catchment were observed. Both internal and external factors could be identified as driving forces for the formation of structures and patterns in the artificial catchment. Initial structures formed by the construction process and initial substrate characteristics were decisive for the distribution and flow of water. External factors like episodic events triggered erosion and dissection during this initial phase, promoted by the low vegetation cover and the unconsolidated sandy substrate. The transformation of the initial geo-system into areas with evolving terrestrial or aquatic characteristics and from a very episodic to a more permanent stream network and discharge, together with the observed vegetation dynamics increased site diversity and heterogeneity with respect to water and nutrient availability and transformation processes compared to the more homogenous conditions at point zero. 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. Artificially created catchments could be a suitable tool to study these initial developments at the landscape scale under known, designed and defined boundary conditions. Y1 - 2013 U6 - https://doi.org/10.1016/j.proenv.2013.06.010 SN - 1878-0296 VL - 19 SP - 86 EP - 95 ER - TY - GEN A1 - Biber, Peter A1 - Seifert, Stefan A1 - Zaplata, Markus Klemens A1 - Schaaf, Wolfgang A1 - Pretzsch, Hans A1 - Fischer, Anton T1 - Relationships between substrate, surface characteristics, and vegetation in an initial ecosystem T2 - Biogeosciences N2 - We investigated surface and vegetation dynamics in the artificial initial ecosystem “Chicken Creek” (Lusatia, Germany) in the years 2006–2011 across a wide spectrum of empirical data. We scrutinized three overarching hypotheses concerning (1) the relations between initial geomorphological and substrate characteristics with surface structure and terrain properties, (2) the effects of the latter on the occurrence of grouped plant species, and (3) vegetation density effects on terrain surface change. Our data comprise and conflate annual vegetation monitoring results, biennial terrestrial laser scans (starting in 2008), annual groundwater levels, and initially measured soil characteristics. The empirical evidence mostly confirms the hypotheses, revealing statistically significant relations for several goal variables: (1) the surface structure properties, local rill density, local relief energy and terrain surface height change; (2) the cover of different plant groups (annual, herbaceous, grass-like, woody, Fabaceae), and local vegetation height; and (3) terrain surface height change showed significant time-dependent relations with a variable that proxies local plant biomass. Additionally, period specific effects (like a calendar-year optimum effect for the occurrence of Fabaceae) were proven. Further and beyond the hypotheses, our findings on the spatiotemporal dynamics during the system’s early development grasp processes which generally mark the transition from a geo-hydro-system towards a bio-geo-hydro system (weakening geomorphology effects on substrate surface dynamics, while vegetation effects intensify with time), where pure geomorphology or substrate feedbacks are changing into vegetation–substrate feedback processes. Y1 - 2013 U6 - https://doi.org/10.5194/bg-10-8283-2013 VL - 10 SP - 8283 EP - 8303 ER - TY - GEN A1 - Ulrich, Werner A1 - Piwczynski, Marcin A1 - Zaplata, Markus Klemens A1 - Winter, Susanne A1 - Schaaf, Wolfgang A1 - Fischer, Anton T1 - Small-scale spatial variability in phylogenetic community structure during early plant succession depends on soil properties T2 - Oecologia N2 - During early plant succession, the phylogenetic structure of a community changes in response to important environmental filters and emerging species interactions. We traced the development of temperate-zone plant communities during the first 7 years of primary succession on catchment soils to explore patterns of initial species assembly. We found pronounced small-scale differences in the phylogenetic composition of neighbouring plant assemblages and a large-scale trend towards phylogenetic evenness. This small-scale variability appears to be mediated by soil properties, particularly carbonate content. Therefore, abiotic environmental conditions might counteract or even supersede the effects of interspecific competition among closely related species, which are usually predicted to exhibit patterns of phylogenetic evenness. We conclude that theories on phylogenetic community composition need to incorporate effects of small-scale variability of environmental factors. Y1 - 2014 U6 - https://doi.org/10.1007/s00442-014-2954-2 VL - 175 IS - 3 SP - 985 EP - 995 ER - TY - GEN A1 - Schaaf, Wolfgang A1 - Bens, Oliver A1 - Fischer, Anton A1 - Gerke, Horst H. A1 - Gerwin, Werner A1 - Grünewald, Uwe A1 - Holländer, Hartmut M. A1 - Kögel-Knabner, Ingrid A1 - Mutz, Michael A1 - Schloter, Michael A1 - Schulin, Rainer A1 - Veste, Maik A1 - Winter, Susanne A1 - Hüttl, Reinhard F. T1 - Patterns and processes of initial terrestrial-ecosystem development T2 - Journal of Plant Nutrition and Soil Science N2 - Ecosystems are characterized as complex systems with abiotic and biotic processes interacting between the various components that have evolved over long-term periods. Most ecosystem studies so far have been carried out in mature systems. Only limited knowledge exists on the very initial phase of ecosystem development. Concepts on the development of ecosystems are often based on assumptions and extrapolations with respect to structure–process interactions in the initial stage. To characterize the effect of this initial phase on structure and functioning of ecosystems in later stages, it is necessary to disentangle the close interaction of spatial and temporal patterns of ecosystem structural assemblages with processes of ecosystem development. The study of initial, less complex systems could help to better identify and characterize coupled patterns and processes. This paper gives an overview of concepts for the initial development of different ecosystem compartments and identifies open questions and research gaps. The artificial catchment site “Chicken Creek” is introduced as a new research approach to investigate these patterns and processes of initial ecosystem development under defined boundary conditions. This approach allows to integrate the relevant processes with related pattern and structure development over temporal and spatial scales and to derive thresholds and stages in state and functioning of ecosystems at the catchment level. KW - soils KW - pedogenesis KW - vegetation succession KW - microbial succession KW - artificial catchment Y1 - 2011 U6 - https://doi.org/10.1002/jpln.201000158 SN - 1522-2624 VL - 174 IS - 2 SP - 229 EP - 239 ER - TY - GEN A1 - Ulrich, Werner A1 - Zaplata, Markus Klemens A1 - Winter, Susanne A1 - Schaaf, Wolfgang A1 - Fischer, Anton A1 - Soliveres, Santiago A1 - Gotelli, Nicholas J. T1 - Species interactions and random dispersal rather than habitat filtering drive community assembly during early plant succession T2 - Oikos N2 - Theory on plant succession predicts a temporal increase in the complexity of spatial community structure and of competitive interactions: initially random occurrences of early colonising species shift towards spatially and competitively structured plant associations in later successional stages. Here we use long-term data on early plant succession in a German post mining area to disentangle the importance of random colonisation, habitat filtering, and competition on the temporal and spatial development of plant community structure. We used species co-occurrence analysis and a recently developed method for assessing competitive strength and hierarchies (transitive versus intransitive competitive orders) in multispecies communities. We found that species turnover decreased through time within interaction neighbourhoods, but increased through time outside interaction neighbourhoods. Successional change did not lead to modular community structure. After accounting for species richness effects, the strength of competitive interactions and the proportion of transitive competitive hierarchies increased through time. Although effects of habitat filtering were weak, random colonization and subsequent competitive interactions had strong effects on community structure. Because competitive strength and transitivity were poorly correlated with soil characteristics, there was little evidence for context dependent competitive strength associated with intransitive competitive hierarchies. Y1 - 2016 U6 - https://doi.org/10.1111/oik.02658 VL - 125 IS - 5 SP - 698 EP - 707 ER - TY - GEN A1 - Ulrich, Werner A1 - Piwczynski, Marcin A1 - Zaplata, Markus Klemens A1 - Winter, Susanne A1 - Schaaf, Wolfgang A1 - Fischer, Anton T1 - Soil conditions and phylogenetic relatedness influence total community trait space during early plant succession T2 - Journal of Plant Ecology N2 - The total space of traits covered by the members of plant communities is an important parameter of ecosystem functioning and complexity. We trace the variability of trait space during early plant succession and ask how trait space co-varies with phylogenetic community structure and soil conditions. Particularly, we are interested in the small-scale variability in trait space and the influence of biotic and abiotic filters. We use data on species richness and soil conditions from the first 7 years of initial succession of an artificial catchment in north-eastern Germany. Total functional attribute diversity serves as a proxy to total trait space. Total trait space steadily increased during succession. We observed high small-scale variability in total trait space that was positively correlated with species richness and phylogenetic segregation and negatively correlated with total plant cover. Trait space increased with soil carbonate content, while pH and the fraction of sandy material behaved indifferently. Our results indicate that during early succession, habitat filtering processes gain importance leading to a lesser increase in trait space than expected from the increase in species richness alone. Y1 - 2014 U6 - https://doi.org/10.1093/jpe/rtt048 VL - 7 IS - 4 SP - 321 EP - 329 ER - TY - GEN A1 - Gerwin, Werner A1 - Schaaf, Wolfgang A1 - Biemelt, Detlef A1 - Fischer, Anton A1 - Winter, Susanne A1 - Hüttl, Reinhard F. T1 - The artificial catchment "Chicken Creek" (Lusatia, Germany) - A landscape laboratory for interdisciplinary studies of initial ecosystem development T2 - Ecological Engineering Y1 - 2009 U6 - https://doi.org/10.1016/j.ecoleng.2009.09.003 SN - 0925-8574 VL - 35 IS - 12 SP - 1786 EP - 1796 ER -