The third dimension in landscape metrics analysis applied to Central Alentejo-Portugal

Landscape metrics have been widely developed over the last two decades, although the question remains: How does landscape metrics relates with ecological processes? One of the major recent developments in landscape metrics analysis was the third dimension integration. Topography has an extremely important role on ecosystems function and structure, even though the common analysis in landscape ecology only conceives planimetric surface which leads to some erroneous results, particularly in mountain areas. The analytical process tested patch, class and landscape metrics behavior in 11 sample areas of 100 sqkm each in several topographical conditions of Central Alentejo. It is presented the significance analysis of the results achieved in planimetric and 3D environments

Benchmarking local ecological performance using ecological footprint accounts

Ecological footprint is good at telling us how much we weight relative to global ecological ressources. However it tells us nothing on their geographical origin and makes no distinction be-tween ecological ressources used from distant or local land. Moreover it does not measure theintensity of exploitation of soils or other sustainability considerations like biodiversity loss. There-fore the results provided by the footprint calculation are barely suitable for planning and policydesign, as information on real use of local land is lost in the process of calculation. This issuesare well known and are part of the research agenda set by the footprint research community andrecommendations has been made to deal with them. The research community already use various metrics to compute the ecological footprint: global hectares, actual hectares and disturbed hectares. The increasing use of input-output technics has also enhanced the localization of the footprint. In this paper all the metrics are used in conjunction with input-output techniques to produce four ecological performance indicators of a local economy taking in account: its global weight on the planet, its degree of dependence on distant ecological ressources, the sustainability of its farming practices, and the quantity of local fertile land not yet used in a bioproductive way. This four performance indicators are then plotted together giving an easy visualizing tool to compare various alternative scenariosBenchmarking ; local ; ecological performance ; footprint accounts

How do ecological resilience metrics relate to community stability and collapse?

The concept of ecological resilience (the amount of disturbance a system can absorb before collapsing and reorganizing) holds potential for predicting community change and collapse—increasingly common issues in the Anthropocene. Yet neither the predictions nor metrics of resilience have received rigorous testing. The crossscale resilience model, a leading operationalization of resilience, proposes resilience can be quantified by the combination of diversity and redundancy of functions performed by species operating at different scales. Here, we use 48 years of sub-continental avian community data aggregated at multiple spatial scales to calculate resilience metrics derived from the cross-scale resilience model (i.e., cross-scale diversity, cross-scale redundancy, within-scale redundancy, and number of body mass aggregations) and test core predictions inherent to community persistence and change. Specifically, we ask how cross-scale resilience metrics relate community stability and collapse. We found low mean cross-correlation between species richness and cross-scale resilience metrics. Resilience metrics constrained the magnitude of community fluctuations over time (mean species turnover), but resilience metrics but did not influence variability of community fluctuations (variance in turnover). We show shifts in resilience metrics closely predict community collapse: shifts in cross-scale redundancy preceded abrupt changes in community composition, and shifts in cross-scale diversity synchronized with abrupt changes in community composition. However, we found resilience metrics only weakly relate to maintenance of particular species assemblages over time. Our results distinguish ecological resilience from ecological stability and allied concepts such as elasticity and resistance: we show communities may fluctuate widely yet still be resilient. Our findings also differentiate the roles of functional redundancy and diversity as metrics of resilience and reemphasize the importance of considering resilience metrics from a multivariate perspective. Finally, we support the contention that ecological stability is nested within ecological resilience: stability predicts the behavior of systems within an ecological regime, and resilience predicts the maintenance of regimes and behavior of systems collapsing into alternative regimes

Ecological network metrics: Opportunities for synthesis

Network ecology provides a systems basis for approaching ecological questions, such as factors that influence biological diversity, the role of particular species or particular traits in structuring ecosystems, and long-term ecological dynamics (e.g., stability). Whereas the introduction of network theory has enabled ecologists to quantify not only the degree, but also the architecture of ecological complexity, these advances have come at the cost of introducing new challenges, including new theoretical concepts and metrics, and increased data complexity and computational intensity. Synthesizing recent developments in the network ecology literature, we point to several potential solutions to these issues: integrating network metrics and their terminology across sub-disciplines; benchmarking new network algorithms and models to increase mechanistic understanding; and improving tools for sharing ecological network research, in particular model data provenance, to increase the reproducibility of network models and analyses. We propose that applying these solutions will aid in synthesizing ecological sub-disciplines and allied fields by improving the accessibility of network methods and models

Applying Landscape Ecological Metrics on Land Use Change in Lanyang Plain

Land use is the human activity affecting by economical, cultural, political and historical factors and presents complex, uncertainty and spatiotemporal characteristics. Understanding of land use change and its trend are necessary for understanding the environmental problems. Nestled between the Pacific Ocean in the east and the Central and Snow Mountains in the north and southwest, Lanyang Plain is one of Taiwan¡¦s most picturesque and secluded geographical areas. However, due to the great construction, Taipei-Yilan highway, the regional landscape structure on a large scale in this area has been directly changed. The original ecological function was thus deteriorated a lot. Conflicts between ecological and socio-economic aspects tend to obstruct the implementation of traditional landscape policy instruments. In this study, land use data in 1982, 1984, 1994, and 2002 surveyed by the government were collected to analyze land use change. After classifying land use categories from the original data, landscape structure in landscape and class scale levels are quantified by calculating landscape metrics. The quantified indices as well as the related events and their driving forces are discussed further. Proper mitigation strategies are then proposed as the suggestions for future management.

Evaluating Enterprize Delivery Using the TYPUS Metrics and the KILT Mode

The goal of this work is the technical, ecological, environmental and social examination of the life-cycle (LC) of any product (consumable, service, production) using the TYPUS metrics and the KILT model. The life-cycle starts when the idea of a product is born and lasts until complete dismissal through design, implementation and operation, etc. In the first phases requirements’ specification, analysis, several design steps (global plan, detailed design, assembly design, etc.) are followed by part manufacturing, assembly, testing, diagnostics and operation, advertisement, service, maintenance, etc. Then finally disassembly and dismissal are coming, but dismissal can be substituted by re-cycling (e.g. melting the metals) or re-use (used parts applications). Qualitative and quantitative evaluations of enterprise results are supported by the new models and metrics

Prioritising the best use of biomass resources: conceptualising trade-offs

02.09.13 KB. Ok to add report to Spiral. Authors hold copyrightUsing biomass to provide energy services is one of the most versatile options for increasing the proportion of renewable energy in the existing system. This report reviews metrics used to compare alternative bio-energy pathways and identifies limitations inherent in the way that they are calculated and interpreted. It also looks at how companies and investors approach strategic decisions in the bio-energy area. Bio-energy pathways have has physical and economic attributes that can be measured or modelled. These include: the capital cost, operating cost, emissions to air, land and water. Conceptually, comparing alternative pathways is as simple as selecting the attributes and metrics you consider to be most important and ranking the alternative pathways accordingly. At an abstract level there is good agreement about which features of bio-energy pathways are desirable, but there is little agreement about which performance metrics best capture all the relevant information about a bio-energy pathway. Between studies there is also a great deal of variation and this impedes comparison. Common metrics describe energetic performance, economic performance, environmental performance (emissions, land and water use), and social and ecological performance. Compound metrics may be used to integrate multiple attributes but their highly aggregate nature may make them difficult to interpret. Insights that may be drawn from the analysis include:

The application of network analysis to assess the structure and function of aquatic food webs : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Ecology at Massey University, Manawatu, New Zealand

The health of aquatic communities is under threat globally by anthropogenic impacts. A healthy ecological community is one that maintains its structure and function over time in the face of disturbance (i.e., they are stable). If we are to effectively monitor change in ecological health and instigate appropriate environmental management responses, then we first need to measure ecological health appropriately. Most methods of indicating ecological health in rivers measure structural aspects of a community, with little attention given to functional aspects. Ecological network analysis (ENA) provides a range of food web metrics that can measure both structural and functional aspects of ecological communities. The aim of this thesis was to apply ENA metrics to assess the structure and function of aquatic ecosystems and explore how they may change with habitat. In a general comparison of aquatic ecosystems, I found that rivers, lakes and estuaries have structurally similar food webs, except have lower neighbourhood connectivity which is reminiscent of unstable habitats. Through species extinction simulations of aquatic energy flow networks, I showed that aquatic food webs were most stable when trophic cascades were weak and average trophic levels were small. In examining the effects of riparian deforestation in Taranaki rivers, dietary changes altered the structure of riverine macroinvertebrate communities considerably and drove greater community respiration. In the Hutt River, I modelled changes in the biomass of trout (exotic predator) and periphyton, and showed that more periphyton, but not more trout, can result in greater community temporal variability. Furthermore, increased trout and periphyton can drive more interspecific competition. I also demonstrated the need for managers to consider the impacts of decisions on adjacent ecosystems as well as target ecosystem by showing that the Hutt River and Wellington Harbour respond substantially different to increases in algal biomass. Finally in rivers differing in nutrient enrichment the Manawatu, I showed that food webs in enriched rivers may be more stable to random species loss but more susceptible to species loss from floods. Similarly to riparian deforestation, highly enriched rivers had greater community respiration (excluding microbial activity), which may exacerbate hypoxic conditions and drive the loss of sensitive species