In order to predict which ecosystem functions are most at risk from biodiversity loss, meta-analy... more In order to predict which ecosystem functions are most at risk from biodiversity loss, meta-analyses have generalised results from biodiversity experiments over different sites and ecosystem types. In contrast, comparing the strength of biodiversity effects across a large number of ecosystem processes measured in a single experiment permits more direct comparisons. Here, we present an analysis of 418 separate measures of 38 ecosystem processes. Overall, 45 % of processes were significantly affected by plant species richness, suggesting that, while diversity affects a large number of processes not all respond to biodiversity. We therefore compared the strength of plant diversity effects between different categories of ecosystem processes, grouping processes according to the year of measurement, their biogeochemi-cal cycle, trophic level and compartment (above-or belowground) and according to whether they were measures of biodiversity or other ecosystem processes, biotic or abiotic and static or dynamic. Overall, and for several individual processes, we found that biodiversity effects became stronger over time. Measures of the carbon cycle were also affected more strongly by plant species richness than were the measures associated with the nitrogen cycle. Further, we found greater plant species richness effects on measures of biodiversity than on other processes. The differential effects of plant diversity on the various types of ecosystem processes indicate that future research and political effort should shift from a general debate about whether biodiversity loss impairs ecosystem functions to focussing on the specific functions of interest and ways to preserve them individually or in combination.
The rise and decline of pre-Columbian cultures in coastal Peru has been the subject of numerous s... more The rise and decline of pre-Columbian cultures in coastal Peru has been the subject of numerous studies. Availability of and access to water have long been recognised as the key issues for the habitability of valley oases in the coastal desert where agriculture depends on seasonal river discharge from the Andes. In general, the reason for cultural changes has often been seen in ‘natural disasters’ or climatic changes. We propose an alternative qualitative model to explain changes of human-environment interactions in the region. This model focuses on patterns arising from the exploitation of and adaptation to the limited – but on the whole not necessarily declining – resources of water and arable land. Agriculture along the rivers of the Peruvian coastal desert was probably first practised in the wide, gently sloping lowland valley floor areas at the foot of the Andes, where large tracts of land can be irrigated with relatively low expenditure of labour. Subsequent expansion of agriculture necessitated the utilisation of progressively marginal areas along the upstream reaches of the rivers. While the spatially limited valley floor areas can to a certain extent be irrigated with short irrigation canals, irrigation of the steep valley slopes of upvalley areas requires the labour-intensive construction and maintenance of canals and terraced fields in difficult – and arguably less productive – terrain. Diversion of water onto up-valley terraced fields can be expected to have reduced water availability in the lowland valley floor fields. Thus, the adaptation to the constraints of one limited resource (irrigable land) may have led to a suboptimal exploitation of another limited resource (water), leading to an overall decline in agricultural productivity per unit of arable land. Such a feedback between land use and water availability is consistent with archaeological findings such as declining population density and increasing conflict during the Early Intermediate Period.
Based on closely integrated investigations of terrestrial and marine environmental
archives in So... more Based on closely integrated investigations of terrestrial and marine environmental archives in South Africa, the project RAIN (Regional Archives for Integrated iNvestigations) assesses the compatibility of marine and continental archives of past climate and ecosystem change and contributes to an enhanced knowledge of land-ocean interactions following transport pathways from source to sink. Previous studies have shown that combined analyses of multiple parameters in more than one environmental system contribute signifi cantly to an improved understanding of climate system dynamics in southern Africa. Thus, RAIN integrates paleo-information obtained from paired terrestrial and marine archives in climatically contrasting areas. Methodologically, a set of complimentary methods ranging from standard analyses such as grain size distribution to advanced (in-)organic geochemical analyses will be applied in four strongly interlinked subject-oriented subprojects. A fi fth focus will be on student education and training in a capacity building subproject. Considering different temporal and spatial scales, ranging from sub-continental to regional scales and decadal to millennial time frames, expected outcomes of each subproject are anticipated to provide information about a range of paleoenvironmental changes driven by Late Quaternary climate variations and the nature of anthropogenic impacts on ecosystem dynamics during the last 200 years in southern Africa. As part of the SPACES (Science Partnerships for the Assessment of Complex Earth System Processes) programme funded by the German Federal Ministry of Education and Research (BMBF), RAIN focuses on the three major rainfall zones of South Africa. Thus, a further great potential for decoding the climate dynamics in southern Africa lies in the connection and comparison of data from its western and eastern boundary using a W-E transect utilising identical, state-of-the-art methods applied to all archives. Through this, RAIN aims to provide improved understanding of the impacts of complex interactions of atmospheric and oceanic driving forces on regional hydrological cycles and climate conditions in different climate regions of sub-Saharan Africa
The most common used methods to determine sediment yield from small catchments (km²) are based on... more The most common used methods to determine sediment yield from small catchments (km²) are based on water sampling strategies, as flow depths are often too small and irregular to use optical sensors. In several sediment yield studies automatic sampling devices triggered by water stage recorders were used to determine sediment transport. Based on two field studies in a small loess-covered catchment in southwestern Germany (Kraichgau) and a former uranium-mining area in eastern Germany (Thurengia) we discuss several factors determining the accuracy of sediment yield data. These factors include accuracy of discharge measurements, timing of sampling, water sampling intervals and methods, as well as selected sediment concentration measurement techniques.
Jena, Universiẗat, Habil.-Schr.,2000. Zusammenfassung Eingebettet in das interdisziplinäre DFG-Sc... more Jena, Universiẗat, Habil.-Schr.,2000. Zusammenfassung Eingebettet in das interdisziplinäre DFG-Schwerpunktprogramm „Siedlungsentwicklung und Staatenbildung im Tibetischen Himalaya“ wurden Untersuchungen zum Landschaftswandel im Thakkhola (Mustang District) in Nepal durchgeführt. Das nördlich des Himalaya-Hauptkamms gelegene Untersuchungsgebiet (≈ 28°45‘ N / 83°45‘ E), das dem obere Einzugsgebiet der Kali Gandaki entspricht, ist durch semi-arides Klima, entsprechend spärliche Vegetationsbedeckung, und eine extreme Reliefenergie gekennzeichnet. Das Nebeneinander von rezenter Besiedlung und zahlreichen Burg-, Siedlungs- und Flurwüstungen in diesem, an der Höhengrenze der Ökumene gelegenen, Raum zeugt von einer durch Stabilitäts- und Instabilitätsphasen gekennzeichneten Siedlungsentwicklung. Ziel der Arbeit war, die Wechselwirkungen zwischen der Landschaftsdynamik und der Siedlungsentwicklung zu untersuchen und mögliche geoökologische Determinanten der Siedlungsentwicklung zu identifizi...
ABSTRACT This chapter contains sections titled: IntroductionData on Soil ErosionSoil Erosion Data... more ABSTRACT This chapter contains sections titled: IntroductionData on Soil ErosionSoil Erosion Data Sets on the National ScaleConclusions AcknowledgementsReferences
The rise and decline of pre-Columbian cultures in coastal Peru has been the subject of numerous s... more The rise and decline of pre-Columbian cultures in coastal Peru has been the subject of numerous studies. Availability of and access to water have long been recognised as the key issues for the habitability of valley oases in the coastal desert where agriculture depends on seasonal river discharge from the Andes. In general, the reason for cultural changes has often been seen in ‘natural disasters’ or climatic changes. We propose an alternative qualitative model to explain changes of human-environment interactions in the region. This model focuses on patterns arising from the exploitation of and adaptation to the limited – but on the whole not necessarily declining – resources of water and arable land. Agriculture along the rivers of the Peruvian coastal desert was probably first practised in the wide, gently sloping lowland valley floor areas at the foot of the Andes, where large tracts of land can be irrigated with relatively low expenditure of labour. Subsequent expansion of agric...
ABSTRACT In order to reduce sediment yield from arable land to receiving water bodies, a sediment... more ABSTRACT In order to reduce sediment yield from arable land to receiving water bodies, a sediment retention area was set aside at the outlet of a first order-catchment (0.62 km²) with silty loess soils and a high proportion of arable land use. A 3-year field experiment showed, that the sediment retention area, which can as well be considered as a wide, gently sloping filter strip with natural succession, is an effective measure to diminish sediment yield from soil erosion within the catchment. The retention area, equal of 1% of the arable land within the catchment, reduced sediment yield from the catchment by an average of 60% over the 3-year period. Once a good ground cover is reached, the sediment trap efficiency reaches values of more than 65%. Analyzing a set of erosion events, showed a clear relationship between the peak discharge and the single event sediment trap efficiency.
geometry of active faults and 2) the ratio of the elapsed time from the latest fault-event agains... more geometry of active faults and 2) the ratio of the elapsed time from the latest fault-event against the mean recurrence interval. The Eastern Yokote Basin Fault Zone is an east-dipping reverse fault with 60 km in length, and is separated into the northern and southern segments. The northern segment ruptured in AD 1896 and generated the large earthquake with M 7.2, whereas there was no surface rupture on the southern segment. I conducted a survey for the activity of the southern segment of this fault zone with my colleagues in 2009. I will show the result of the calculation of the probability of the occurrence of the large earthquake caused by rupture of the both segments.
A trait-based experimental approach to understand the mechanisms underlying biodiversityndashecos... more A trait-based experimental approach to understand the mechanisms underlying biodiversityndashecosystem functioning relationships, Basic and Applied Ecology (2014), http://dx.Abstract Plant functional characteristics may drive plant species richness effects on ecosystem 35 processes. Consequently, the focus of biodiversity-ecosystem functioning (BEF) experiments has expanded from the manipulation of plant species richness to manipulating functional trait composition. Involving ecophysiological plant traits in the experimental design might allow for a better understanding of how species loss alters ecosystem processes. Here we provide the theoretical background, design and first results of the 'Trait-Based Biodiversity 40 Experiment' (TBE), established in 2010 that directly manipulates the trait composition of experimental plant communities. Analysis of six plant traits related to resource acquisition and use were analyzed using principal component analysis of 60 grassland species. The resulting two main axes describe gradients in functional similarity, and were used as the basis for designing plant communities 45 with different functional and species diversity levels. Using such an approach allowed us to manipulate different levels of complementarity in spatial and temporal plant resource acquisition. In contrast to previous biodiversity experiments, the TBE is designed according to more realistic scenarios of non-random species loss along orthogonal axes of species trait dissimilarities. This allows us to tease apart the relative importance of selection and 50 complementarity effects on multiple ecosystem processes, and to mechanistically study the consequences of plant community simplification. Zusammenfassung Es wird angenommen, dass funktionelle Pflanzenmerkmale verantwortlich sind für 55 beobachtete Effekte von Pflanzendiversität auf Ökosystemfunktionen, wodurch sich der Fokus der Biodiversitätsforschung von der Betrachtung der Effekte von Pflanzenartenzahlen hin zu der Betrachtung von Pflanzenmerkmalen in einer Gemeinschaft erweitert hat. Die Page 4 of 32 A c c e p t e d M a n u s c r i p t Berücksichtigung von funktionellen Pflanzenmerkmalen hilft möglichweise zu verstehen, wie der Verlust von Arten Ökosystemprozesse beeinflusst. Unseres Wissens wurde jedoch die 60 funktionelle Ähnlichkeit verschiedener Pflanzenarten zueinander noch nie als Grundlage für ein Grasland-Biodiversitätsexperiment genutzt. Wir präsentieren den theoretischen Hintergrund, das experimentelle Design und erste Ergebnisse eines sogenannten ‚Trait-Based Biodiversity Experiments' (TBE), welches 2010 im Rahmen des Jena Experimentes etabliert wurde und bei welchem direkt die funktionelle 65 Diversität von Pflanzeneigenschaften manipuliert wurde. Mithilfe einer Hauptkomponentenanalyse wurden sechs Pflanzenmerkmale von 60 Graslandarten analysiert, die bedeutend für Ressourcenaufnahme und -nutzung sind. Dabei bildeten die Pflanzenarten, die entlang zweier unabhängiger Achsen angeordnet waren, Gradienten in ihrer funktionellen Ähnlichkeit, die als Basis für das Design des TBE dienten. 70 Auf neu angelegten Versuchsflächen etablierten wir Pflanzengemeinschaften mit unterschiedlicher Pflanzenartenzahl, die sich in ihrer räumlichen und zeitlichen funktionellen Komplementarität unterscheiden. Das neuartige Design des TBE erlaubt es uns in Zukunft den relativen Einfluss von Selektions-und Komplementaritätseffekten auf Ökosystemprozesse zu bestimmen und ermöglicht die mechanistische Erforschung der 75 Konsequenzen von vereinfachten Lebensgemeinschaften.
In order to predict which ecosystem functions are most at risk from biodiversity loss, meta-analy... more In order to predict which ecosystem functions are most at risk from biodiversity loss, meta-analyses have generalised results from biodiversity experiments over different sites and ecosystem types. In contrast, comparing the strength of biodiversity effects across a large number of ecosystem processes measured in a single experiment permits more direct comparisons. Here, we present an analysis of 418 separate measures of 38 ecosystem processes. Overall, 45 % of processes were significantly affected by plant species richness, suggesting that, while diversity affects a large number of processes not all respond to biodiversity. We therefore compared the strength of plant diversity effects between different categories of ecosystem processes, grouping processes according to the year of measurement, their biogeochemical cycle, trophic level and compartment (above-or belowground) and according to whether they were measures of biodiversity or other ecosystem processes, biotic or abiotic and static or dynamic. Overall, and for several individual processes, we found that biodiversity effects became stronger over time. Measures of the carbon cycle were also affected more strongly by plant species richness than were the measures associated with the nitrogen cycle.
Background: Infiltration is a key process in determining the water balance, but so far effects of... more Background: Infiltration is a key process in determining the water balance, but so far effects of earthworms, soil texture, plant species diversity and their interaction on infiltration capacity have not been studied.
In order to predict which ecosystem functions are most at risk from biodiversity loss, meta-analy... more In order to predict which ecosystem functions are most at risk from biodiversity loss, meta-analyses have generalised results from biodiversity experiments over different sites and ecosystem types. In contrast, comparing the strength of biodiversity effects across a large number of ecosystem processes measured in a single experiment permits more direct comparisons. Here, we present an analysis of 418 separate measures of 38 ecosystem processes. Overall, 45 % of processes were significantly affected by plant species richness, suggesting that, while diversity affects a large number of processes not all respond to biodiversity. We therefore compared the strength of plant diversity effects between different categories of ecosystem processes, grouping processes according to the year of measurement, their biogeochemi-cal cycle, trophic level and compartment (above-or belowground) and according to whether they were measures of biodiversity or other ecosystem processes, biotic or abiotic and static or dynamic. Overall, and for several individual processes, we found that biodiversity effects became stronger over time. Measures of the carbon cycle were also affected more strongly by plant species richness than were the measures associated with the nitrogen cycle. Further, we found greater plant species richness effects on measures of biodiversity than on other processes. The differential effects of plant diversity on the various types of ecosystem processes indicate that future research and political effort should shift from a general debate about whether biodiversity loss impairs ecosystem functions to focussing on the specific functions of interest and ways to preserve them individually or in combination.
The rise and decline of pre-Columbian cultures in coastal Peru has been the subject of numerous s... more The rise and decline of pre-Columbian cultures in coastal Peru has been the subject of numerous studies. Availability of and access to water have long been recognised as the key issues for the habitability of valley oases in the coastal desert where agriculture depends on seasonal river discharge from the Andes. In general, the reason for cultural changes has often been seen in ‘natural disasters’ or climatic changes. We propose an alternative qualitative model to explain changes of human-environment interactions in the region. This model focuses on patterns arising from the exploitation of and adaptation to the limited – but on the whole not necessarily declining – resources of water and arable land. Agriculture along the rivers of the Peruvian coastal desert was probably first practised in the wide, gently sloping lowland valley floor areas at the foot of the Andes, where large tracts of land can be irrigated with relatively low expenditure of labour. Subsequent expansion of agriculture necessitated the utilisation of progressively marginal areas along the upstream reaches of the rivers. While the spatially limited valley floor areas can to a certain extent be irrigated with short irrigation canals, irrigation of the steep valley slopes of upvalley areas requires the labour-intensive construction and maintenance of canals and terraced fields in difficult – and arguably less productive – terrain. Diversion of water onto up-valley terraced fields can be expected to have reduced water availability in the lowland valley floor fields. Thus, the adaptation to the constraints of one limited resource (irrigable land) may have led to a suboptimal exploitation of another limited resource (water), leading to an overall decline in agricultural productivity per unit of arable land. Such a feedback between land use and water availability is consistent with archaeological findings such as declining population density and increasing conflict during the Early Intermediate Period.
Based on closely integrated investigations of terrestrial and marine environmental
archives in So... more Based on closely integrated investigations of terrestrial and marine environmental archives in South Africa, the project RAIN (Regional Archives for Integrated iNvestigations) assesses the compatibility of marine and continental archives of past climate and ecosystem change and contributes to an enhanced knowledge of land-ocean interactions following transport pathways from source to sink. Previous studies have shown that combined analyses of multiple parameters in more than one environmental system contribute signifi cantly to an improved understanding of climate system dynamics in southern Africa. Thus, RAIN integrates paleo-information obtained from paired terrestrial and marine archives in climatically contrasting areas. Methodologically, a set of complimentary methods ranging from standard analyses such as grain size distribution to advanced (in-)organic geochemical analyses will be applied in four strongly interlinked subject-oriented subprojects. A fi fth focus will be on student education and training in a capacity building subproject. Considering different temporal and spatial scales, ranging from sub-continental to regional scales and decadal to millennial time frames, expected outcomes of each subproject are anticipated to provide information about a range of paleoenvironmental changes driven by Late Quaternary climate variations and the nature of anthropogenic impacts on ecosystem dynamics during the last 200 years in southern Africa. As part of the SPACES (Science Partnerships for the Assessment of Complex Earth System Processes) programme funded by the German Federal Ministry of Education and Research (BMBF), RAIN focuses on the three major rainfall zones of South Africa. Thus, a further great potential for decoding the climate dynamics in southern Africa lies in the connection and comparison of data from its western and eastern boundary using a W-E transect utilising identical, state-of-the-art methods applied to all archives. Through this, RAIN aims to provide improved understanding of the impacts of complex interactions of atmospheric and oceanic driving forces on regional hydrological cycles and climate conditions in different climate regions of sub-Saharan Africa
The most common used methods to determine sediment yield from small catchments (km²) are based on... more The most common used methods to determine sediment yield from small catchments (km²) are based on water sampling strategies, as flow depths are often too small and irregular to use optical sensors. In several sediment yield studies automatic sampling devices triggered by water stage recorders were used to determine sediment transport. Based on two field studies in a small loess-covered catchment in southwestern Germany (Kraichgau) and a former uranium-mining area in eastern Germany (Thurengia) we discuss several factors determining the accuracy of sediment yield data. These factors include accuracy of discharge measurements, timing of sampling, water sampling intervals and methods, as well as selected sediment concentration measurement techniques.
Jena, Universiẗat, Habil.-Schr.,2000. Zusammenfassung Eingebettet in das interdisziplinäre DFG-Sc... more Jena, Universiẗat, Habil.-Schr.,2000. Zusammenfassung Eingebettet in das interdisziplinäre DFG-Schwerpunktprogramm „Siedlungsentwicklung und Staatenbildung im Tibetischen Himalaya“ wurden Untersuchungen zum Landschaftswandel im Thakkhola (Mustang District) in Nepal durchgeführt. Das nördlich des Himalaya-Hauptkamms gelegene Untersuchungsgebiet (≈ 28°45‘ N / 83°45‘ E), das dem obere Einzugsgebiet der Kali Gandaki entspricht, ist durch semi-arides Klima, entsprechend spärliche Vegetationsbedeckung, und eine extreme Reliefenergie gekennzeichnet. Das Nebeneinander von rezenter Besiedlung und zahlreichen Burg-, Siedlungs- und Flurwüstungen in diesem, an der Höhengrenze der Ökumene gelegenen, Raum zeugt von einer durch Stabilitäts- und Instabilitätsphasen gekennzeichneten Siedlungsentwicklung. Ziel der Arbeit war, die Wechselwirkungen zwischen der Landschaftsdynamik und der Siedlungsentwicklung zu untersuchen und mögliche geoökologische Determinanten der Siedlungsentwicklung zu identifizi...
ABSTRACT This chapter contains sections titled: IntroductionData on Soil ErosionSoil Erosion Data... more ABSTRACT This chapter contains sections titled: IntroductionData on Soil ErosionSoil Erosion Data Sets on the National ScaleConclusions AcknowledgementsReferences
The rise and decline of pre-Columbian cultures in coastal Peru has been the subject of numerous s... more The rise and decline of pre-Columbian cultures in coastal Peru has been the subject of numerous studies. Availability of and access to water have long been recognised as the key issues for the habitability of valley oases in the coastal desert where agriculture depends on seasonal river discharge from the Andes. In general, the reason for cultural changes has often been seen in ‘natural disasters’ or climatic changes. We propose an alternative qualitative model to explain changes of human-environment interactions in the region. This model focuses on patterns arising from the exploitation of and adaptation to the limited – but on the whole not necessarily declining – resources of water and arable land. Agriculture along the rivers of the Peruvian coastal desert was probably first practised in the wide, gently sloping lowland valley floor areas at the foot of the Andes, where large tracts of land can be irrigated with relatively low expenditure of labour. Subsequent expansion of agric...
ABSTRACT In order to reduce sediment yield from arable land to receiving water bodies, a sediment... more ABSTRACT In order to reduce sediment yield from arable land to receiving water bodies, a sediment retention area was set aside at the outlet of a first order-catchment (0.62 km²) with silty loess soils and a high proportion of arable land use. A 3-year field experiment showed, that the sediment retention area, which can as well be considered as a wide, gently sloping filter strip with natural succession, is an effective measure to diminish sediment yield from soil erosion within the catchment. The retention area, equal of 1% of the arable land within the catchment, reduced sediment yield from the catchment by an average of 60% over the 3-year period. Once a good ground cover is reached, the sediment trap efficiency reaches values of more than 65%. Analyzing a set of erosion events, showed a clear relationship between the peak discharge and the single event sediment trap efficiency.
geometry of active faults and 2) the ratio of the elapsed time from the latest fault-event agains... more geometry of active faults and 2) the ratio of the elapsed time from the latest fault-event against the mean recurrence interval. The Eastern Yokote Basin Fault Zone is an east-dipping reverse fault with 60 km in length, and is separated into the northern and southern segments. The northern segment ruptured in AD 1896 and generated the large earthquake with M 7.2, whereas there was no surface rupture on the southern segment. I conducted a survey for the activity of the southern segment of this fault zone with my colleagues in 2009. I will show the result of the calculation of the probability of the occurrence of the large earthquake caused by rupture of the both segments.
A trait-based experimental approach to understand the mechanisms underlying biodiversityndashecos... more A trait-based experimental approach to understand the mechanisms underlying biodiversityndashecosystem functioning relationships, Basic and Applied Ecology (2014), http://dx.Abstract Plant functional characteristics may drive plant species richness effects on ecosystem 35 processes. Consequently, the focus of biodiversity-ecosystem functioning (BEF) experiments has expanded from the manipulation of plant species richness to manipulating functional trait composition. Involving ecophysiological plant traits in the experimental design might allow for a better understanding of how species loss alters ecosystem processes. Here we provide the theoretical background, design and first results of the 'Trait-Based Biodiversity 40 Experiment' (TBE), established in 2010 that directly manipulates the trait composition of experimental plant communities. Analysis of six plant traits related to resource acquisition and use were analyzed using principal component analysis of 60 grassland species. The resulting two main axes describe gradients in functional similarity, and were used as the basis for designing plant communities 45 with different functional and species diversity levels. Using such an approach allowed us to manipulate different levels of complementarity in spatial and temporal plant resource acquisition. In contrast to previous biodiversity experiments, the TBE is designed according to more realistic scenarios of non-random species loss along orthogonal axes of species trait dissimilarities. This allows us to tease apart the relative importance of selection and 50 complementarity effects on multiple ecosystem processes, and to mechanistically study the consequences of plant community simplification. Zusammenfassung Es wird angenommen, dass funktionelle Pflanzenmerkmale verantwortlich sind für 55 beobachtete Effekte von Pflanzendiversität auf Ökosystemfunktionen, wodurch sich der Fokus der Biodiversitätsforschung von der Betrachtung der Effekte von Pflanzenartenzahlen hin zu der Betrachtung von Pflanzenmerkmalen in einer Gemeinschaft erweitert hat. Die Page 4 of 32 A c c e p t e d M a n u s c r i p t Berücksichtigung von funktionellen Pflanzenmerkmalen hilft möglichweise zu verstehen, wie der Verlust von Arten Ökosystemprozesse beeinflusst. Unseres Wissens wurde jedoch die 60 funktionelle Ähnlichkeit verschiedener Pflanzenarten zueinander noch nie als Grundlage für ein Grasland-Biodiversitätsexperiment genutzt. Wir präsentieren den theoretischen Hintergrund, das experimentelle Design und erste Ergebnisse eines sogenannten ‚Trait-Based Biodiversity Experiments' (TBE), welches 2010 im Rahmen des Jena Experimentes etabliert wurde und bei welchem direkt die funktionelle 65 Diversität von Pflanzeneigenschaften manipuliert wurde. Mithilfe einer Hauptkomponentenanalyse wurden sechs Pflanzenmerkmale von 60 Graslandarten analysiert, die bedeutend für Ressourcenaufnahme und -nutzung sind. Dabei bildeten die Pflanzenarten, die entlang zweier unabhängiger Achsen angeordnet waren, Gradienten in ihrer funktionellen Ähnlichkeit, die als Basis für das Design des TBE dienten. 70 Auf neu angelegten Versuchsflächen etablierten wir Pflanzengemeinschaften mit unterschiedlicher Pflanzenartenzahl, die sich in ihrer räumlichen und zeitlichen funktionellen Komplementarität unterscheiden. Das neuartige Design des TBE erlaubt es uns in Zukunft den relativen Einfluss von Selektions-und Komplementaritätseffekten auf Ökosystemprozesse zu bestimmen und ermöglicht die mechanistische Erforschung der 75 Konsequenzen von vereinfachten Lebensgemeinschaften.
In order to predict which ecosystem functions are most at risk from biodiversity loss, meta-analy... more In order to predict which ecosystem functions are most at risk from biodiversity loss, meta-analyses have generalised results from biodiversity experiments over different sites and ecosystem types. In contrast, comparing the strength of biodiversity effects across a large number of ecosystem processes measured in a single experiment permits more direct comparisons. Here, we present an analysis of 418 separate measures of 38 ecosystem processes. Overall, 45 % of processes were significantly affected by plant species richness, suggesting that, while diversity affects a large number of processes not all respond to biodiversity. We therefore compared the strength of plant diversity effects between different categories of ecosystem processes, grouping processes according to the year of measurement, their biogeochemical cycle, trophic level and compartment (above-or belowground) and according to whether they were measures of biodiversity or other ecosystem processes, biotic or abiotic and static or dynamic. Overall, and for several individual processes, we found that biodiversity effects became stronger over time. Measures of the carbon cycle were also affected more strongly by plant species richness than were the measures associated with the nitrogen cycle.
Background: Infiltration is a key process in determining the water balance, but so far effects of... more Background: Infiltration is a key process in determining the water balance, but so far effects of earthworms, soil texture, plant species diversity and their interaction on infiltration capacity have not been studied.
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Papers by Jussi Baade
archives in South Africa, the project RAIN (Regional Archives for Integrated iNvestigations)
assesses the compatibility of marine and continental archives of past climate and ecosystem
change and contributes to an enhanced knowledge of land-ocean interactions following
transport pathways from source to sink. Previous studies have shown that combined analyses
of multiple parameters in more than one environmental system contribute signifi cantly to
an improved understanding of climate system dynamics in southern Africa. Thus, RAIN
integrates paleo-information obtained from paired terrestrial and marine archives in
climatically contrasting areas. Methodologically, a set of complimentary methods ranging
from standard analyses such as grain size distribution to advanced (in-)organic geochemical
analyses will be applied in four strongly interlinked subject-oriented subprojects. A
fi fth focus will be on student education and training in a capacity building subproject.
Considering different temporal and spatial scales, ranging from sub-continental to regional
scales and decadal to millennial time frames, expected outcomes of each subproject are
anticipated to provide information about a range of paleoenvironmental changes driven by Late Quaternary climate variations and the nature of anthropogenic impacts on ecosystem
dynamics during the last 200 years in southern Africa.
As part of the SPACES (Science Partnerships for the Assessment of Complex Earth System
Processes) programme funded by the German Federal Ministry of Education and Research
(BMBF), RAIN focuses on the three major rainfall zones of South Africa. Thus, a further
great potential for decoding the climate dynamics in southern Africa lies in the connection
and comparison of data from its western and eastern boundary using a W-E transect utilising
identical, state-of-the-art methods applied to all archives. Through this, RAIN aims to
provide improved understanding of the impacts of complex interactions of atmospheric and
oceanic driving forces on regional hydrological cycles and climate conditions in different
climate regions of sub-Saharan Africa
archives in South Africa, the project RAIN (Regional Archives for Integrated iNvestigations)
assesses the compatibility of marine and continental archives of past climate and ecosystem
change and contributes to an enhanced knowledge of land-ocean interactions following
transport pathways from source to sink. Previous studies have shown that combined analyses
of multiple parameters in more than one environmental system contribute signifi cantly to
an improved understanding of climate system dynamics in southern Africa. Thus, RAIN
integrates paleo-information obtained from paired terrestrial and marine archives in
climatically contrasting areas. Methodologically, a set of complimentary methods ranging
from standard analyses such as grain size distribution to advanced (in-)organic geochemical
analyses will be applied in four strongly interlinked subject-oriented subprojects. A
fi fth focus will be on student education and training in a capacity building subproject.
Considering different temporal and spatial scales, ranging from sub-continental to regional
scales and decadal to millennial time frames, expected outcomes of each subproject are
anticipated to provide information about a range of paleoenvironmental changes driven by Late Quaternary climate variations and the nature of anthropogenic impacts on ecosystem
dynamics during the last 200 years in southern Africa.
As part of the SPACES (Science Partnerships for the Assessment of Complex Earth System
Processes) programme funded by the German Federal Ministry of Education and Research
(BMBF), RAIN focuses on the three major rainfall zones of South Africa. Thus, a further
great potential for decoding the climate dynamics in southern Africa lies in the connection
and comparison of data from its western and eastern boundary using a W-E transect utilising
identical, state-of-the-art methods applied to all archives. Through this, RAIN aims to
provide improved understanding of the impacts of complex interactions of atmospheric and
oceanic driving forces on regional hydrological cycles and climate conditions in different
climate regions of sub-Saharan Africa