An Eternal Flame: The Elemental Governance of Wildfire’s Pasts, Presents and Futures

Views of fire in the contemporary physical sciences arguably accord with Heraclitus’ proposal that ‘all things are an exchange for fire, and fire for all things, as goods for gold and gold for goods.’ Fire is a media, as John Durham Peters has stated, a species of transformative biochemical reactions between the flammable gases found in air, such as oxygen, and those found in fuels, such as plants. Inspired by an ignition source, these materials react and transform themselves and their surrounds into light and heat energy, carbon dioxide, water vapour, char and much else besides. Fire is conjunctural, durational and transformative. Fire is a dialectician, at once consuming living and dead organic matter and providing both the space and ingredients for new and renewed organic life. In this article, we draw upon our experience of combustible contexts—Australia, Canada and the Philippines—to consider the diverse ways in which fire is today framed as a social problem, an ecological process, an ancient tool, a natural disaster, a source of economic wealth and much more. In this way, we seek to explore the value and limits of ‘elemental thinking’ in relation to the planetary predicaments described by ‘the Anthropocene’

On non-equilibrium and nomadism : knowledge, diversity and global modernity in Drylands (and beyond…)

Drylands worldwide, together with the variously nomadic peoples who live there, are associated with the incidence of poverty and environmental degradation. Corresponding assertions of pending social and ecological collapse have paved the way for hegemonic development and policy interventions focusing on the settlement of formerly mobile populations, reductions of livestock numbers, land privatisation and shifts towards commercial and tightly regulated production. Despite the wealth of expertise and monetary resources involved, however, these initiatives have rarely been successful, either in socio-economic or environmental terms. Our aim in this paper is to engage critically with both the conceptual underpinnings and empirical consequences of a globalising modernity as these have played out in dryland environments, and in relation to practices of mobility amongst the peoples who such environments are associated. We draw on a debate that exists in ecology regarding the sources and types of dynamic behaviour driving ecological systems. Drylands have become a particular focus of this debate. In these environments extreme and unpredictable variability in rainfall are considered (by some) to confer non-equilibrium dynamics by continually disrupting the tight consumer-resource relations that would otherwise pull the components of the system towards equilibrium. This implies that livestock grazing in drylands, widely thought to cause degradation and ‘desertification’ through detrimental management practices including mobility and the maximising of herd reproductive rates, in fact might not be causing irreversible ecological change. Or at least not through exceeding a density-dependent equilibrial relationship with forage availability. We attempt to extend discussion by thinking through the cultural and historical contexts leading to a particular ‘shoehorning’ of the dynamics associated with non-equilibrium and nomadism into a conceptual framework that emphasises the desirability of stability, equilibrium and predictability. In doing so, we draw on the explanatory power of theories of conceptual and ritual purification (associated with anthropologist Mary Douglas); of the empowered panopticon society with its requirements for diffuse and minutely controlled surveillance and regulation (cf. Foucault), and of the ideological differences between State and Nomad science as considered by philosophers Gilles Deleuze and Félix Guattari

Environmental determinants of the ecology and distribution of Acacia tortilis under arid conditions in Qatar

PhD ThesisScrub or woodland communities dominated by Acacia tortilis form one of the few tree-dominated natural ecosystems in the hyper-arid climate of Qatar, making it a very important tree species that provides an essential habitat both for native animals and domestic livestock. However, the conservation and sustainable management of this tree has so far been neglected and it is now severely impacted by overgrazing and wood fuel collection. This research investigates the main environmental, ecological and management factors affecting the growth and distribution of Acacia tortilis in Qatar, including the factors affecting its regeneration. It also aims to guide the implementation of conservation programmes and development of a strategy to forestall deforestation and prevent the extinction of Acacia tortilis in Qatar. Initially, field survey, remote sensing and GIS techniques, together with univariate and multivariate statistical modelling techniques, were used to explore environmental influences on distribution of A. tortilis in Qatar at a national scale. Different vegetation indices (VIs), normalized difference vegetation index (NDVI), soil adjusted vegetation index (SAVI), were derived for a time series of Landsat TM/ETM+ images for 1998 and 2010 and tested using ground-truth data to explore the temporal dynamics of Acacia-dominated ecosystems which indicated substantial reduction in vegetation greenness in 2010 than 1998. The initial approach had limited success due to difficulties of identifying Acacia tortilis communities accurately on satellite images due to the sparsity of tree cover and indicates the limitations of using remote sensing methods for tracing vegetation dynamics in Qatar and similar arid and hyper arid environments. The multinomial logistic regression model has a superior ability to predict Acacia distribution and is a suitable method in the prediction of the occurrence of different vegetation types. Phytogeographical investigations of the environmental and biotic factors that control the distribution of the Acacia tortilis at a local scale, in both areas protected and unprotected from human land use impacts, demonstrate that topographic factors and their control on soil and water conditions are fundamental determinants. The distinctive topography of Qatar has resulted in a heterogeneous soil landscape with extreme contrasts of chemical and physical soil conditions within and between depressions and more elevated positions in soil toposequences. Depressional land forms are more suitable for the Acacia tree growth than the surrounding higher ground because ENVIRONMENTAL DETERMINANTS OF ACACIA TORTILIS IN QATAR II depression soils have greater soil water content, soil depth, organic carbon and available phosphorus contents. Conversely, the absence of Acacia trees in summit areas is related to severe limitations for tree growth, including negligible soil water content and shallow soil depth caused by impeding bedrock or cemented horizons resulting in drought stress, as well as large contents of gypsum and/or CaCO3 in soils. The slope-controlled movement of eroded soil material, water and plant debris, and the localised leaching of soluble salts, are suggested to be important processes that lead to improved soil quality and better tree growth in depressions. The regeneration of Acacia tortilis through seedling establishment is perhaps surprisingly shown to be greater in the unprotected than in protected areas. This is attributed to the importance of ingestion by large mammals (mainly domestic herbivores) on the germination and recruitment of Acacia seedlings. The greater frequency of Acacia saplings in depressions within the unprotected areas is, however, also attributed to the presence of greater amounts of soil water, soil depth, available phosphorus, and organic carbon. Although the action of browsing may be regarded as positive, most anthropogenic impacts were shown to have negative effects on the condition and distribution of Acacia tortilis. The results proved that the impacts of cutting and browsing were severe in the unprotected sites, despite the evidence of more active regeneration. It is concluded that there is an urgent need to review the provision and management of protected habitats for Acacia tortilis in Qatar. It is suggested that cutting for domestic use should be restricted; that conservation efforts should be concentrated in depressions that favour tree growth; and that the livestock numbers should be limited to enable seedling establishment without excessive browsing.“Qatar University”, for sponsoring my Ph.D. researc

Nonequilibrium Statistical Physics in Ecology: Vegetation Patterns, Animal Mobility and Temporal Fluctuations

Esta tesis doctoral se centra en la aplicación de la física estadística del no equilibrio al estudio de problemas ecológicos de diferente naturaleza. En primer lugar se desarrollan modelos teóricos para explicar la formación de patrones de vegetación en algunas regiones donde el agua es escasa, prestando especial atención al papel que juegan las interacciones entre plantas. En la segunda parte se abordan problemas de búsqueda en los que los individuos son capaces de comunicarse entre sí. El objetivo es comprender el comportamiento de las gacelas que habitan la estepa centroasiática. En un último capitulo se estudia el efecto que tiene un medio externo cuyos características cambian en el tiempo sobre distintas propiedades de los ecosistemas. Situando problemas de tan diversa naturaleza en un marco común se pretende mostrar el poder de la física estadística como herramienta interdisciplinar.This thesis focuses on the application of nonequilibrium statistical physics to different ecological problems. In the first part we study the formation of vegetation patterns in water-limited systems, emphasizing the role of nonlocal interactions among plants. In the second part we develop mathematical models to explain the collective searching behavior in some animal species, where individuals communicate among them. The objective of this chapter is to build the theoretical tools to study foraging behavior in Mongolian gazelles, which is the aim of the next chapter. Finally, the effect of environmental variability on the robustness and evolution of ecosystems is studied. Studying problems of different nature within the common framework provided by statistical physics we aim to show its relevant role as an interdisciplinary tool

TRY plant trait database - enhanced coverage and open access

Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

Prioritising organisational circular economy strategies by applying the partial order set theory: Tool and case study

This study presents a methodology to solve circular economy multiple indicators system decision-making problems by applying the Partial Order Set Theory (POSET). To this end, a user-friendly tool was developed to allow the prioritisation of alternative scenarios or circularity strategies based on the value that each of them takes for different circular economy indicators (both quantitative and qualitative), but avoiding processes involving aggregation and weight among the indicators. The developed tool also makes it possible to model different restrictions that facilitate its adaptation to any case study and the incorporation of the results into the decision-making process. Moreover, it allows a graphical representation of the results to be obtained by using Hasse diagrams. Finally, the developed tool was validated by means of its application to a case study with the aim of prioritising circular economy strategies in an organisation belonging to the construction sector. Specifically, this organisation presented some opportunities for improvement, mainly related to the use of recycled and recirculated materials and effluents, waste recycling, energy efficiency and the proximity of suppliers, among others. The sensitivity analysis of the considered restrictions showed not only the robustness of the results obtained with the tool but also its great influence in circular economy multiple indicators decision-making solutions.Funding for open access charge: CRUE-Universitat Jaume

Does Land Abundance Explain African Institutions?

I show how abundant land and scarce labor shaped African institutions before colonial rule. I present a model in which exogenous suitability of the land for agriculture and endogenously evolving population determine the existence of land rights, slavery, and polygyny. I then use cross-sectional data on pre-colonial African societies to demonstrate that, consistent with the model, the existence of land rights, slavery, and polygyny occurred in those parts of Africa that were the most suitable for agriculture, and in which population density was greatest. Next, I use the model to explain institutions among the Egba of southwestern Nigeria from 1830 to 1914. While many Egba institutions were typical of a land-abundant environment, they sold land and had disputes over it. These exceptions were the result of a period of land scarcity when the Egba first arrived at Abeokuta and of heterogeneity in the quality of land.Africa, institutions, land rights, slavery, polygyny