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.

Uptake of [15N] Ammonium and [15N]Nitrate in a 140-Year-Old Spruce Stand (Picea abies) in the Fichtelgebirge (NE Bavaria)

Abstract: A 15N tracer-experiment was carried out in a 140-year-old spruce stand (Picea abies (L.) Karst.) in the Fichtelgebirge (NE-Bavaria, Germany). Highly enriched (98 at%) [15N]ammonium and [15N]nitrate were applied as tracers by simulation of a deposition of 41.3 mol N ha−1 with 11 water m−2. To examine seasonal variations of uptake by spruce and understorey vegetation, different plots were labelled in spring, summer and autumn 1994. One aim of the present study was to perfect a method of preparation of soil extracts for isotope ratio mass spectrometry (IRMS) measurements. Ammonium and nitrate from soil extracts were prepared for IRMS measurements by steam distillation and subsequent freeze drying. Additionally, tracer distribution and transformations in the soil nitrogen pools were examined. Ammonium, nitrate and total nitrogen were examined in the organic layer and the upper 10 cm of the mineral soil during 3 months after the first tracer application in spring 1994. In July 1994, three months after...

The Significance of Assimilatory Starch for Growth in Arabidopsis thaliana Wild-Type and Starchless Mutants

Abstract: Vegetative growth is generally assumed to reach maximum rates when plants invest as much carbohydrate as possible in the growth of new leaves (Monsi and Murata 1970; Schulze 1983). Only with new leaves are additional production organs established which by compound interest contribute to further growth (Harper 1989; Diemer et al. 1992). Growth rates are eventually limited by supply of resources, such as water and nutrients, or light in the case of self-shading (Schulze and Chapin 1987). Storage of carbohydrates could be expected to compete with growth of leaves and roots and thus reduce the maximum growth rate (Chapin et al. 1990). Nevertheless, carbohydrate storage is a very common phenomenon in the plant kingdom and production of assimilatory starch occurs in chloroplasts of all leaf tissues. Therefore, in this chapter we investigate the functional role of assimilatory starch and its interaction with growth using a starchless mutant compared with a wild type of Arabidopsis thaliana (Schulze et al. 1991).

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