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This chapter discusses the use of ecological niche modeling to study species invasions, and more specifically to identify and understand genuine exceptions to ecological niche equivalency between native and introduced ranges of species. In addition, it examines the degree to which the geographic course of species’ invasions can be anticipated based on scenopoetic variables and biotic interactions. The chapter also reviews practical considerations that must be taken into account when exploring the utility of ecological niche models in understanding species’ invasions, such as using niche conservatism to predict likely changes in the distributional potential of invasive species under scenarios of changing environmental conditions. Finally, it describes caveats and limitations of the approach and outlines future research directions and challenges involved in the application of niche modeling ideas in species invasions.

Temperature is one of the most important abiotic factors affecting marine ecological processes: this chapter outlines global temperature variations and their consequences for ecosystem structure and function. It starts by explaining the factors that control ocean temperature, describing the resulting global patterns of thermal variation, and providing predictions for future changes in these patterns. It then examines mechanisms by which organismal level temperature impacts influence biotic interactions and ultimately translate to changes in species distribution and community structure. It examines evidence from whole-community manipulations to understand how key features of ecosystem structure and function may respond to projected temperature change. Finally, it highlights how temperature interacts with other abiotic stressors, both as a driver of variation in these stressors and due to the complex nature of the combined interactive effects of these stressors on ecological processes.

This chapter begins with a definition of endozoochory, which refers to plant dispersal where viable seeds are defaecated or regurgitated by animals. Because of the biotic interaction involved, endozoochorous seed dispersal largely depends on the behavioural components of the dispersing vectors, such as foraging and seed handling, movement away from the parent tree, and defaecation or regurgitation. This makes endozoochorous seed dispersal clumped and non-random, in contrast to most abiotically dispersal methods. The main selective forces driving the evolution of dispersal-related traits include avoidance of kin competition by escaping high seed and seedling mortality near the parent tree, directing dispersal towards suitable habitat, and colonisation of new habitat as a risk-spreading strategy. Changes in landscape composition may affect endozoochorous seed dispersal through changes in plant habitat configuration and vector community composition and behaviour.

Our next major question is, how can we characterize the sediment as a habitat for biota? Marine sediments range from coarse gravels in areas subjected to much wave and current action, to muds typical of low-energy estuarine areas and to fine silts and clays in deep-sea sediments. The settling velocity of those particles and the ability of any particle to be re-suspended, moved, and redeposited depends on the prevailing hydrographic regime (e.g. see Open University 2002). The latter will in turn influence the transport of a species´ dispersal stages, especially larvae which will then be allowed to settle following metamorphosis under the appropriate hydrographic conditions (defined as hydrographic concentration). Hence the presence of fine sediments will indicate the depositing/accreting areas which may also be suitable for passively settling organisms. Clearly the particle size is of major importance in characterizing sediments, although sediments can also be categorized by their origin (fluvial, biogenic, cosmogenic, etc.) and their material (quartz, carbonates, clays, etc.) (Open University 2002). On a typical sandy beach the coarsest particles lie at the top of the beach and grade down to the finest sediments at the waterline. The top of the beach is dry and there is much windblown sand, since coarse sands drain rapidly, whereas at the lower end of the beach the sediments are wet, with frequent standing pools. Coarse sediment is found at the top of the shore because as the waves break on the beach the heaviest particles sediment out first. Finer particles remain in suspension longer and are carried seaward on the wave backwash. Beaches change their slope over the seasons, being steeper in winter and shallower in summer. A greater degree of wave energy will produce steeper beaches, as particles are pushed up the beach and so may be stored there, whereas gentle waves produce shallow, sloping beaches. Waves hitting the shore obliquely will create sediment movement as longshore drift. Subtidally, waves are important in distributing and affecting sediments down to depths of 100 m, but the effect decreases exponentially with depth and so the dominant subtidal influences on sediment transport are currents.