Changes In Forest Ecosystem Nutrition

The long-term productivity of forest ecosystems depends on the cycling of nutrients. The effect of carbon dioxide fertilization on forest productivity may ultimately be limited by the rate of nutrient cycling. Contemporary and future disturbances such as climatic warming, N-deposition, deforestation, short rotation sylviculture, fire (both wild and controlled), and the invasion of exotic species all place strains on the integrity of ecosystem nutrient cycling. Global differences in climate, soils, and species make it difficult to extrapolate even a single important study worldwide. Despite advances in the understanding of nutrient cycling and carbon production in forests, many questions remain. The chapters in this volume reflect many contemporary research priorities. The thirteen studies in this volume are arranged in the following subject groups: • N and P resorption from foliage worldwide, along chronosequences and along elevation gradients; • Litter production and decomposition; • N and P stoichiometry as affected by N deposition, geographic gradients, species changes, and ecosystem restoration; • Effects of N and P addition on understory biomass, litter, and soil; • Effects of burning on soil nutrients; • Effects of N addition on soil fauna.

From the research results and discussions presented in this book it becomes clear that a profound understanding of the various interrelationships of the nutritional aspects allows the implementation of specific management strategies to improve stability and productivity of forest ecosystems. In particular the effects of environmental changes as related to the impacts of air pollution, global change and land use on nutrient uptake and cycling processes in forest ecosystems are dealt with in detail. The book is divided into six main issues and each topic contains reviews as well as selected results of recent studies.

Brings together much of the recent literature on nutrient cycling due to conversion of forests to croplands, pastures, and plantation forests. It explains why nutrients are often very critical in tropical humid ecosystems and discusses principles that can guide land managers to conserve nutrients and sustain productivity.

Inland West, their historical origins, assessments of available management tools, and analyses of the various choices available to policymakers. Its goal is to help people understand the Inland West forests so that public policies can reflect a constructive and realistic framework in which forests can be managed for sustained health. This resource is the product of a scientific workshop where 35 participants, including scientists, resource managers, administrators, and environmentalists, addressed the forest health problem in the Inland West. Synthesis chapters integrate the diverse knowledge and experience which participants brought to the workshop. They identify and link together many of the ecological, social, and administrative conditions which have created the forest health problem in the West. The book is unique in that it reflects a process that fostered the use of academic research, field realities, and industrial knowledge to define an interdisciplinary problem, establish rational policy objectives, and set-up “do-able” management approaches. The following topics are analyzed: Assessing forest ecosystem health in the Inland West Historical and anticipated changes in forest ecosystems in the Inland West Defining and measuring forest health Historical range of variability as a tool for evaluating ecosystem change Administrative barriers to implementing forest health problems Economic and social dimensions of the forest health problem Fire management Ecosystem and landscape management

Deforestation and land use change have led to a strong reduction of tropical forest cover during the last decades. Climate change will amplify the pressure to the remaining refuges in the next years. In addition, tropical regions are facing increasing atmospheric inputs of nutrients, which will have unknown consequences for the structure and functioning of these systems, no matter if they are within protected areas or not. Even remote areas are expected to receive rising amounts of nutrients. The effects of higher rates of atmospheric nutrient deposition on the biological diversity and ecosystem functioning of tropical ecosystems are poorly understood and our knowledge of nutrient fluxes and nutrient limitation in tropical forest ecosystems is still limited. Yet, it will be of paramount importance to know the effects of increased nutrient availability to conserve these ecosystems with their biological and functional diversity. During the last years, research efforts have more and more focused on the understanding of the role of nutrients in tropical ecosystems and several coordinated projects have been established that study the effects of experimental nutrient addition. This Research Topic combines results from experiments and from observational studies with the aim to review and conclude on our current knowledge on the role of additional nutrients in ecosystems.

The long-term productivity of forest ecosystems depends on the cycling of nutrients. The effect of carbon dioxide fertilization on forest productivity may ultimately be limited by the rate of nutrient cycling. Contemporary and future disturbances such as climatic warming, N-deposition, deforestation, short rotation sylviculture, fire (both wild and controlled), and the invasion of exotic species all place strains on the integrity of ecosystem nutrient cycling. Global differences in climate, soils, and species make it difficult to extrapolate even a single important study worldwide. Despite advances in the understanding of nutrient cycling and carbon production in forests, many questions remain. The chapters in this volume reflect many contemporary research priorities. The thirteen studies in this volume are arranged in the following subject groups: • N and P resorption from foliage worldwide, along chronosequences and along elevation gradients; • Litter production and decomposition; • N and P stoichiometry as affected by N deposition, geographic gradients, species changes, and ecosystem restoration; • Effects of N and P addition on understory biomass, litter, and soil; • Effects of burning on soil nutrients; • Effects of N addition on soil fauna.