Impacts Of Anthropic Disturbance On Microarthropods

Anthropic disturbances reduce ecosystem functionality by disrupting interactions between aboveground and belowground communities. Interactions between plants and belowground biota (i.e., soil fauna) shape ecosystem functions, diversity, and structure aboveground. In disturbance scenarios, some plant community attributes might influence the response of secondary consumers and decomposers (i.e., soil fauna) to new conditions. Both resource provision (i.e., litter), habitat availability, and trophic interactions can be affected by disturbance (i.e., management). The type and intensity of the disturbance regulate the community response aboveground, but response patterns for soil fauna are still unclear. A challenge for sustainable forest management is predicting belowground changes based on aboveground structural conditions and traits. Understanding the relationship between disturbance, plant traits, and soil fauna dynamics is relevant for predicting functional changes at the ecosystem level. Yet, the relative importance of those factors for soil fauna community structure in disturbance scenarios is uncertain. This dissertation explores this research gap in a woodland system by focusing on two disturbance types: 1) a gradient of strip-harvest intensity and 2) multiple nutrient enrichment. In woodlands, firewood harvest and fertilization are standard silvicultural practices with unknown consequences for soil biodiversity and function. First, I characterized the quantitative relationship between a gradient of harvest intensity and the microarthropod community response. For this, I analyzed the interplay of plant community structure, litterfall provision, and microarthropod community structure (Chapter 2). Second, I analyzed the impact of nutrient enrichment on soil fauna using the addition of three macronutrients: nitrogen (N), phosphorus (P), and potassium (K). This is the first time a multiple nutrient addition experiment, including K, was implemented in a temperate woody community. Using this experiment, I quantified the short-term impacts of multiple nutrient enrichment on microarthropod community structure (Chapter 3) and their functional role (Chapter 4). Overall, the results collectively suggest that intermediate levels of disturbance intensity and N addition do not represent ecological risks for microarthropod communities and their functional role in the short term. In this work, I discuss and contrast the relative importance of resource provision, resource quality, and plant community structure for microarthropods in woodlands under management. Considering these three aboveground elements can help design sustainable practices that allow soil health conservation and belowground ecosystem service provision.

The effects of human-mediated activities on soil quality and functioning have been assessed. Composition and changes in arthropod community structure and laboratory bioassays were performed on urban soils in order to understand the roles of metal contamination on soil organism activities and distribution. Then, comparison of urban, agricultural, industrial and forest soils were performed, monitoring Collembola species and functional traits composition, in order to assess if the impact of urban environment is greater than other kinds of anthropization. Soil organism community was analysed twice a years for evaluating the role of seasonality on anthropic impacted soils. The different kinds of anthropization firstly affected the abiotic properties of the sites. Agricultural and urban soils were the most impacted soils by human activities, which cause changes in vegetation cover, organic matter amounts and accumulation of hazardous elements and compounds. Soils organisms responded to soil abiotic modifications. In particular, in urban environment soil organisms were strongly reduced at high level of metal contamination, whereas organic matter content and climatic conditions played the main role at low-intermediate soil contamination. Collembola community showed a strong reduction in species richness in agricultural soils, with a consequent domination of few tolerant species. Collembola functional trait distribution was mainly affected by the presence and the type of litter and inputs of contaminants. In particular, agricultural environment favoured organisms with traits adapted to soil life surface, whereas forest soils favoured organisms with euedaphic characteristics. Industrial and urban soils showed organisms with both epiedaphic and euedaphic characteristics.

Soil microarthropods were surveyed for one year in order to see if the theory of island biogeography held true for micro-communities. Soil fauna were collected on a bi-monthly basis at a previously disturbed site in the New Jersey Pine Plains on natural regrowth islands. In conjunction with the survey an experimental survey was also conducted using defaunated soil patches, which were examined on a bi-monthly basis from September 2011- May 2011. Soil fauna on natural regrowth islands responded positively to island area and litter depth, and there was clear separation of soil fauna communities between the main lands the regrowth islands. Defaunated islands displayed changes in community assemblage over time and there were clear differences between soil fauna types and the ability to colonize new island habitats. There was a change in community structure over time as early colonizers were able to prosper for a short amount of time, followed by a slower dispersing suite of microarthropods that were able to establish and flourish in the defaunated habitat for a longer period of time. Overall, the study showed that soil microarthropod communities follow the assumptions of Mac Arthur and Wilson's theory of island biogeography and that certain species are limited by their dispersal capabilities.

Recent years have seen a paradigm shift in our understanding of groundwater–surface water interactions: surface water and aquifers were long considered discrete, separate entities; they are now understood as integral components of a surface–subsurface continuum. This book provides an overview of current research advances and innovative approaches in groundwater–surface water interactions. The 20 research articles and 1 communication cover a wide range of thematic scopes, scales, and experimental and modelling methods across different disciplines (hydrology, aquatic ecology, biogeochemistry, and environmental pollution). The book identifies current knowledge gaps and reveals the challenges in establishing standardized measurement, observation, and assessment approaches. It includes current hot topcis with environmental and societal relevance such as eutrophication, retention of legacy, and emerging pollutants (e.g., pharmaceuticals and microplastics), urban water interfaces, and climate change impacts. The book demonstrates the relevance of processes at groundwater–surface water interfaces for (1) regional water balances and (2) quality and quantity of drinking water resources. As such, this book represents the long-awaited transfer of the above-mentioned paradigm shift in understanding of groundwater–surface water interactions from science to practice.

The Ecology of Sandy Shores provides the students and researchers with a one-volume resource for understanding the conservation and management of the sandy shore ecosystem. Covering all beach types, and addressing issues from the behavioral and physiological adaptations of the biota to exploring the effects of pollution and the impact of man's activities, this book should become the standard reference for those interested in Sandy Shore study, management and preservation. More than 25% expanded from the previous edition Three entirely new chapters: Energetics and Nutrient Cycling, Turtles and Terrestrial Vertebrates, and Benthic Macrofauna Populations New sections on the interstitial environment, seagrasses, human impacts and coastal zone management Examples drawn from virtually all parts of the world, considering all beach types from the most exposed to the most sheltered

Reducing environmental hazard and human impact on different ecosystems, with special emphasis on rural landscapes is the main topic of different environmental policies designed in developed countries and needed in most developing countries. This book covers the bioindication approach of rural landscapes and man managed ecosystems including both urbanised and industrialised ones. The main techniques and taxa used for bioindication are considered in detail. Remediation and contamination is faced with diversity, abundance and dominance of biota, mostly invertebrates. Invertebrate Biodiversity as Bioindicators of Sustainable Landscapes provides a basic tool for students and scientists involved in landscape ecology and planning, environmental sciences, landscape remediation and pollution.

Dr. Timothy Schowalter has succeeded in creating a unique, updated treatment of insect ecology. This revised and expanded text looks at how insects adapt to environmental conditions while maintaining the ability to substantially alter their environment. It covers a range of topics- from individual insects that respond to local changes in the environment and affect resource distribution, to entire insect communities that have the capacity to modify ecosystem conditions.Insect Ecology, Second Edition, synthesizes the latest research in the field and has been produced in full color throughout. It is ideal for students in both entomology and ecology-focused programs. NEW TO THIS EDITION:* New topics such as elemental defense by plants, chaotic models, molecular methods to measure disperson, food web relationships, and more* Expanded sections on plant defenses, insect learning, evolutionary tradeoffs, conservation biology and more* Includes more than 350 new references* More than 40 new full-color figures