Ernst Detlef Schulze

Bio: Ernst Detlef Schulze is an academic researcher from Max Planck Society. The author has contributed to research in topics: Biodiversity & Ecosystem. The author has an hindex of 133, co-authored 670 publications receiving 69504 citations. Previous affiliations of Ernst Detlef Schulze include University of Idaho & University of Utah.

Dispersal ability, trophic position and body size mediate species turnover processes: Insights from a multi‐taxa and multi‐scale approach

Abstract: Aim Despite increasing interest in β‐diversity, that is the spatial and temporal turnover of species, the mechanisms underlying species turnover at different spatial scales are not fully understood, although they likely differ among different functional groups. We investigated the relative importance of dispersal limitations and the environmental filtering caused by vegetation for local, multi‐taxa forest communities differing in their dispersal ability, trophic position and body size. Location Temperate forests in five regions across Germany. Methods In the inter‐region analysis, the independent and shared effects of the regional spatial structure (regional species pool), landscape spatial structure (dispersal limitation) and environmental factors on species turnover were quantified with a 1‐ha grain across 11 functional groups in up to 495 plots by variation partitioning. In the intra‐region analysis, the relative importance of three environmental factors related to vegetation (herb and tree layer composition and forest physiognomy) and spatial structure for species turnover was determined. Results In the inter‐region analysis, over half of the explained variation in community composition (23% of the total explained 35%) was explained by the shared effects of several factors, indicative of spatially structured environmental filtering. Among the independent effects, environmental factors were the strongest on average over 11 groups, but the importance of landscape spatial structure increased for less dispersive functional groups. In the intra‐region analysis, the independent effect of plant species composition had a stronger influence on species turnover than forest physiognomy, but the relative importance of the latter increased with increasing trophic position and body size. Main conclusions Our study revealed that the mechanisms structuring assemblage composition are associated with the traits of functional groups. Hence, conservation frameworks targeting biodiversity of multiple groups should cover both environmental and biogeographical gradients. Within regions, forest management can enhance β‐diversity particularly by diversifying tree species composition and forest physiognomy.

The size and the age of the metabolically active carbon in tree roots.

Abstract: Little is known about the sources and age of C respired by tree roots. Previous research in stems identified two functional pools of non-structural carbohydrates (NSC): an "active" pool supplied directly from canopy photo-assimilates supporting metabolism and a "stored" pool used when fresh C supplies are limited. We compared the C isotope composition of water-soluble NSC and respired CO2 for aspen roots (Populus tremula hybrids) cut off from fresh C supply after stem-girdling or prolonged incubation of excised roots. We used bomb radiocarbon to estimate the time elapsed since C fixation for respired CO2 , water-soluble NSC and structural α-cellulose. While freshly excised roots (mostly <2.9 mm in diameter) respired CO2 fixed <1 year previously, the age increased to 1.6-2.9 year within a week after root excision. Freshly excised roots from trees girdled ~3 months ago had respiration rates and NSC stocks similar to un-girdled trees but respired older C (~1.2 year). We estimate that over 3 months NSC in girdled roots must be replaced 5-7 times by reserves remobilized from root-external sources. Using a mixing model and observed correlations between Δ14 C of water-soluble C and α-cellulose, we estimate ~30% of C is "active" (~5 mg C g-1 ).

Among stand heterogeneity is key for biodiversity in managed beech forests but does not question the value of unmanaged forests: Response to Bruun and Heilmann-Clausen (2021)

Abstract: Schall et al. (2020) assessed how a combination of different forest management systems in managed forest landscapes dominated by European beech may affect the biodiversity (alpha, beta and gamma) of 14 taxonomic groups. Current forest policy and nature conservation often demand for combining uneven-aged managed and unmanaged, set-aside for nature conservation, beech forests in order to promote biodiversity. In contrast to this, Schall et al. (2020) found even-aged shelterwood forests, represented by different developmental phases, to support highest regional (gamma) diversity. By pointing out that unmanaged forests included in our study are not old-growth forests, Bruun and Heilmann-Clausen (2021) challenge our conclusion as not providing sound scientific advice to societies. It is true that the studied unmanaged forests are not representing old-growth forests as defined in the literature. However, we demonstrate the representativeness of our unmanaged forests for current beech forest landscapes of Central Europe, where managed forests were more or less recently set-aside in order to develop old-growth structures. We also show that the managed and recently unmanaged forests in our study already differ distinctively in their forest structures. We use this response to stress the role of forest reserves for promoting certain species groups, and to emphasise their importance as valuable research sites today and in the future. Synthesis and applications. We see two main conclusions from our study. First, unmanaged forests still matter. We agree with Bruun and Heilmann-Clausen (2021) on the general importance of unmanaged, old-growth or long-untouched forests, and we do not question the importance of set-aside forests for biodiversity conservation. However, a complete complementarity to managed systems may only reveal after many decades of natural development. Second, safeguarding biodiversity in largely managed forest landscapes should focus on providing a landscape matrix of different developmental phases with varying environmental conditions rather than on maximising the vertical structure within stands. Such landscapes can partly compensate for structures that are still missing in vital, dense and closed forests recently set-aside or for unsuitable phases that may occur due to a cyclic synchronisation of forest structures in unmanaged forests. © 2021 The Authors. Journal of Applied Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society

The Theory of Island Biogeography

Abstract: Preface to the Princeton Landmarks in Biology Edition vii Preface xi Symbols Used xiii 1. The Importance of Islands 3 2. Area and Number of Speicies 8 3. Further Explanations of the Area-Diversity Pattern 19 4. The Strategy of Colonization 68 5. Invasibility and the Variable Niche 94 6. Stepping Stones and Biotic Exchange 123 7. Evolutionary Changes Following Colonization 145 8. Prospect 181 Glossary 185 References 193 Index 201

Effects of biodiversity on ecosystem functioning: a consensus of current knowledge

Abstract: Humans are altering the composition of biological communities through a variety of activities that increase rates of species invasions and species extinctions, at all scales, from local to global. These changes in components of the Earth's biodiversity cause concern for ethical and aesthetic reasons, but they also have a strong potential to alter ecosystem properties and the goods and services they provide to humanity. Ecological experiments, observations, and theoretical developments show that ecosystem properties depend greatly on biodiversity in terms of the functional characteristics of organisms present in the ecosystem and the distribution and abundance of those organisms over space and time. Species effects act in concert with the effects of climate, resource availability, and disturbance regimes in influencing ecosystem properties. Human activities can modify all of the above factors; here we focus on modification of these biotic controls. The scientific community has come to a broad consensus on many aspects of the re- lationship between biodiversity and ecosystem functioning, including many points relevant to management of ecosystems. Further progress will require integration of knowledge about biotic and abiotic controls on ecosystem properties, how ecological communities are struc- tured, and the forces driving species extinctions and invasions. To strengthen links to policy and management, we also need to integrate our ecological knowledge with understanding of the social and economic constraints of potential management practices. Understanding this complexity, while taking strong steps to minimize current losses of species, is necessary for responsible management of Earth's ecosystems and the diverse biota they contain.

Agricultural sustainability and intensive production practices

Abstract: A doubling in global food demand projected for the next 50 years poses huge challenges for the sustainability both of food production and of terrestrial and aquatic ecosystems and the services they provide to society. Agriculturalists are the principal managers of global useable lands and will shape, perhaps irreversibly, the surface of the Earth in the coming decades. New incentives and policies for ensuring the sustainability of agriculture and ecosystem services will be crucial if we are to meet the demands of improving yields without compromising environmental integrity or public health.

The worldwide leaf economics spectrum

Abstract: Bringing together leaf trait data spanning 2,548 species and 175 sites we describe, for the first time at global scale, a universal spectrum of leaf economics consisting of key chemical, structural and physiological properties. The spectrum runs from quick to slow return on investments of nutrients and dry mass in leaves, and operates largely independently of growth form, plant functional type or biome. Categories along the spectrum would, in general, describe leaf economic variation at the global scale better than plant functional types, because functional types overlap substantially in their leaf traits. Overall, modulation of leaf traits and trait relationships by climate is surprisingly modest, although some striking and significant patterns can be seen. Reliable quantification of the leaf economics spectrum and its interaction with climate will prove valuable for modelling nutrient fluxes and vegetation boundaries under changing land-use and climate.

Carbon Isotope Discrimination and Photosynthesis

Abstract: We discuss the physical and enzymatic bases of carbone isotope discrimination during photosynthesis, noting how knowledge of discrimination can be used to provide additional insight into photosynthetic metabolism and the environmental influences on that process