Seascape ecology
Seascape ecology is a scientific discipline that deals with the causes and ecological consequences of spatial pattern in the marine environment, drawing heavily on conceptual and analytical frameworks developed in terrestrial landscape ecology.[1]
Overview
Seascape ecology, the application of landscape ecology concepts to the marine environment[2] has been slowly emerging since the 1970s,[3][4][5][6][7] yielding new ecological insights and showing growing potential to support the development of ecologically meaningful science-based management practices.[8][9][10][11] For marine systems, the application of landscape ecology came about through a recognition that many of the concepts developed in the theory of island biogeography[12][13] and the study of patch dynamics (precursors to modern landscape ecology) could be applicable to a range of marine environments from plankton patches [14] to patch reefs,[15] inter-tidal mussel beds [16] and seagrass meadows.[17][18]
Progress in the ecological understanding of spatial patterning was not confined to shallow seafloor environments. For the open ocean, advances in ocean observing systems since the 1970s have allowed scientists to map, classify, quantify and track dynamic spatial structure in the form of eddies, surface roughness, currents, runoff plumes, ice, temperature fronts and plankton patches using oceanographic technologies – a theme increasingly referred to as pelagic seascape ecology.[19][20][21] Subsurface structures too, such as internal waves, thermoclines, haloclines, boundary layers and stratification resulting in distinct layering of organisms, is increasingly being mapped and modelled in multiple dimensions.
Like landscape ecologists, seascape ecologists are interested in the spatially explicit geometry of patterns and the relationships between pattern, ecological processes and environmental change. A central tenet in landscape ecology is that patch context matters, where local conditions are influenced by attributes of the surroundings. For instance, the physical arrangement of objects in space, and their location relative to other things, influences how they function.[22]
A landscape ecologist will ask different questions focused at different scales than other scientists, such as: What are the ecological consequences of different shaped patches, patch size, quality, edge geometry, spatial arrangement and diversity of patches across the landscape? At what scale(s) is structure most influential? How do landscape patterns influence the way that animals find food, evade predators and interact with competitors? How does human activity alter the structure and function of landscapes?
Several guiding principles that exist at the core of landscape ecology have made major contributions to terrestrial landscape planning and conservation, but in marine systems our understanding is still in its infancy. The first book on seascape ecology was published in December 2017[23]
Seascapes are defined broadly as spatially heterogeneous and dynamic spaces that can be delineated at a wide range of scales in time and space. With regard to seascapes defined by sampling units, a 1 m2 quadrant can be a valid seascape sample unit (SSU), just as can a 1 km2 analytical window in a geographical information system. The wide diversity of possible focal scales in marine ecology means that the term seascape cannot be used as an indication of scale, or a level of organization.
Seascape patterns
The sea exhibits complex spatial patterning that can be mapped and quantified, such as gradients in plant communities across tidal saltmarshes or the intricate mosaics of patches typical of coral reefs.[24] In the open ocean too, dynamic spatial structure in the form of water currents, eddies, temperature fronts and plankton patches can be measured readily.[25][26] Physical processes such as storms dramatically influence spatial patterning in the environment and human activity can also directly create patch structure, modify mosaic composition and even completely remove elements of the seascape. Furthermore, climate-change induced shifts in species related to water temperature change and sea level rise are driving a gradual reconfiguration of the geography of species and habitats.
The patterns revealed by remote sensing devices are most often mapped and represented using two types of model: (1) collections of discrete patches forming mosaics e.g. as represented in two-dimensional benthic habitat map, or (2) continuously varying gradients in three-dimensional terrain models e.g. in remotely sensed Bathymetric data.[27][28] In landscape ecology, patches can be classified into a binary patch-matrix model based on island biogeography theory where a focal habitat patch type (e.g. seagrasses) is surrounded by an inhospitable matrix (e.g. sand), or a patch-mosaic of interconnected patches, where the interactions of the parts influence the ecological function of the whole mosaic. Both patch and gradient models have provided important insights into the spatial ecology of marine species and biodiversity.
Scale matters
Scale, the spatial or temporal dimensions of a phenomenon, is central to seascape ecology and the topic permeates all applications of a seascape ecology approach from conceptual models through to design of sampling, analyses and interpretation of results.[29] Species and life-stage responses to patchiness and gradients in environmental structure are likely to be scale dependent, therefore, scale selection is an important task in any ecological study. Seascape ecology acknowledges that decisions made for scaling ecological studies influence our perspective and ultimately our understanding of ecological patterns and processes.[30] Historically, marine scientists have played a significant role in communicating the importance of scale in ecology[31]
In 1963, a physical oceanographer, Henry Stommel, published a conceptual diagram that was to have a profound effect on all of the environmental sciences.[32] The diagram [33] depicted variation in sea level height at spatial scales from centimeters to that of the planet and at time scales from seconds to tens of millennia.[34] The oceanographer John Steele (1978) adapted the Stommel diagram to depict the spatial and temporal scales of patchiness in phytoplankton, zooplankton and fish.
Measuring habitat structure at multiple scales is typical in seascape ecology, particularly where a single meaningful scale is not known or not meaningful to the ecological process of interest. Multi-scale measurements have been used to discover the scale at which populations are associated with key habitat features.[35][36] With regard to scaling seascapes, one approach is to select spatial and temporal scales to be ecologically meaningful to the organism’s movements or other processes of interest.[37]
The absence of information, or the lack of continuous observation on the way animals use space through time, can all too often result in insufficient consideration of seascape context potentially resulting in misleading conclusions on the primary drivers of ecological patterns and processes. Pittman and McAlpine (2003)[38] offer a multi-scale framework for scaling ecological studies that integrates hierarchy theory with movement ecology and the concept of ecological neighborhoods.[39] Here the focal scale is guided by the spatial and temporal scales relevant to an ecological process of interest. The focal scale is nested within a spatial hierarchy that incorporates patterns and processes at both finer and broader scales[40]
References
- Pittman SJ, Wiens JA, Wu J, Urban DL (2017) Chapter 16: Landscape ecologist’s perspectives on seascape ecology. p485-494. In Pittman SJ (ed.) Seascape Ecology. John Wiley & Sons Ltd.
- Pittman SJ (2017) Chapter 1: Introducing Seascape Ecology. p3-25. In Pittman SJ (ed.) Seascape Ecology. John Wiley & Sons Ltd.
- Sousa WP (1979) Disturbance in marine intertidal boulder fields: the nonequilibrium maintenance of species diversity. Ecology 60(6): 1225–1239.
- Paine RT, Levin SA (1981) Intertidal landscapes: disturbance and the dynamics of pattern. Ecological Monographs 51(2): 145–178.
- Walsh WJ (1985) Reef fish community dynamics on small artificial reefs: the influence of isolation, habitat structure, and biogeography. Bulletin of Marine Science 36(2):357–376.
- Steele JH (1989) The ocean ‘landscape’. Landscape Ecology 3(3–4): 185–192.
- Jones GP, Andrew NL (1992) Temperate reefs and the scope of seascape ecology. In Battershill CN, Schiel DR, Jones GP, Creese RG, MacDiarmid AB (eds) 2nd International Temperate Reef Symposium (7–10 January 1992). NIWA Marine, Auckland, pp. 63–76.
- Pittman SJ, Kneib RT, Simenstad C. (2011) Practicing coastal seascape ecology. Marine Ecology Progress Series 427, 187-190.
- Olds AD, Connolly RM, Pitt KA, Pittman SJ, Maxwell PS, Huijbers CM, Moore BR, Albert S, Rissik D, Babcock RC, Schlacher TA. (2016) Quantifying the conservation value of seascape connectivity: a global synthesis. Global Ecology and Biogeography 25(1):3-15.
- Pittman SJ, Lepczyk CA, Wedding LM, Parrain C (2017) Chapter 12: Advancing a holistic systems approach in applied seascape ecology. p367-389. In Pittman SJ (ed.) Seascape Ecology. Wiley & Sons Ltd.
- Young MA, Wedding LM, Carr MH (2017) Applying landscape ecology for the design and evaluation of marine protected area networks. p429-464.In Pittman SJ (ed.) Seascape Ecology. Wiley & Sons Ltd
- MacArthur RH,Wilson EO (1967) The Theory of Island Biogeography. Monographs in Population Biology. Princeton University Press, Princeton, NJ.
- Simberloff DS (1974) Equilibrium theory of island biogeography and ecology. Annual review of Ecology and Systematics, 5(1), pp.161-182.
- Steele JH (1978) Spatial Pattern in Plankton Communities. Plenum Press, New York, NY.
- Molles MC Jr (1978) Fish species diversity on model and natural reef patches: experimental insular biogeography. Ecological Monographs 48: 289–305.
- Paine RT, Levin SA (1981) Intertidal landscapes: disturbance and the dynamics of pattern. Ecological Monographs 51(2): 145–178.
- McNeill SE, Fairweather PG (1993) Single large or several small marine reserves? An experimental approach with seagrass fauna. Journal of Biogeography 1: 429–440.
- Robbins BD, Bell SS (1994) Seagrass landscapes: a terrestrial approach to the marine subtidal environment. Trends in Ecology and Evolution 9(8): 301–314.
- Hidalgo M, Secor DH, Browman HI (2016) Observing and managing seascapes: linking synoptic oceanography, ecological processes, and geospatial modelling. ICES Journal of Marine Science, 73(7), pp.1825-1830.
- Kavanaugh MT, Hales B, Saraceno M, Spitz YH, White AE, Letelier RM (2014) Hierarchical and dynamic seascapes: A quantitative framework for scaling pelagic biogeochemistry and ecology. Progress in Oceanography, 120, pp.291-304.
- Scales KL, Alvarez-Berastegui D, Embling C, Ingram S (2017) Chapter 3: Pelagic seascapes. p57-88. In Pittman SJ (ed.) Seascape Ecology. Wiley & Sons Ltd
- Bell SS, McCoy ED, Mushinsky HR (EDS.). 1991. Habitat structure: the physical arrangement of objects in space. Chapman and Hall, London, UK
- Seascape Ecology edited by Simon J. Pittman http://eu.wiley.com/WileyCDA/WileyTitle/productCd-1119084431.html
- Costa B, Walker BK, Dijkstra JA (2017) Chapter 2: Mapping and quantifying seascape patterns. p27-56. In Pittman SJ (ed.) Seascape Ecology. Wiley & Sons Ltd
- Bakun A (1996) Patterns in the Ocean: Ocean Processes and Marine Population Dynamics. University of California Sea Grant, San Diego, CA, United States in cooperation with Centro de Investigaciones Biológicas de Noroeste, La Paz, Baja California Sur, Mexico.
- Scales KL, Alvarez-Berastegui D, Embling C, Ingram S (2017) Chapter 3: Pelagic seascapes. p57-88. In Pittman SJ (ed.) Seascape Ecology. Wiley & Sons Ltd
- McGarigal K, Tagil S, Cushman SA (2009) Surface metrics: an alternative to patch metrics for the quantification of landscape structure. Landscape Ecology 24(3): 433–450.
- Wedding L, Lepczyk C, Pittman S, Friedlander A, Jorgensen S (2011) Quantifying seascape structure: extending terrestrial spatial pattern metrics to the marine realm. Marine Ecology Progress Series 427: 219–232.
- Schneider DC (2001) The rise of the concept of scale in ecology: The concept of scale is evolving from verbal expression to quantitative expression. BioScience 51(7): 545–553.
- Levin SA (1992) The problem of pattern and scale in ecology. Ecology 73: 1943–1967.
- Schneider DC (2017) Chapter 4: Scale and scaling in seascape ecology. p89-117. In Pittman SJ (ed.) Seascape Ecology. Wiley & Sons Ltd.
- Vance TC, Doel RE (2010) Graphical methods and cold war scientific practice: The Stommel diagram’s intriguing journey from the physical to the biological environmental sciences. Historical Studies in the Natural Sciences 40: 1–47.
- Stommel H (1963) Varieties of oceanographic experience. Science 139: 572–576.
- Schneider DC (2017) Chapter 4: Scale and scaling in seascape ecology. p89-117. In Pittman SJ (ed.) Seascape Ecology. Wiley & Sons Ltd.
- Schneider DC, Piatt JF (1986) Scale-dependent correlation of seabirds with schooling fish in a coastal ecosystem. Marine Ecological Progress Series 32: 237–246.
- Pittman SJ, Brown KA (2011) Multi-scale approach for predicting fish species distributions across coral reef seascapes. PLoS ONE 6(5): e20583.
- Pittman SJ, Hile SD, Caldow, C & Monaco ME (2007) Using seascape types to explain the spatial patterns of fish using mangroves in Puerto Rico. Marine Ecology Progress Series 348, 273-284
- Pittman SJ & McAlpine CA (2003) Movements of marine fish and decapod crustaceans: Process, theory and application. Advances in Marine Biology 44, 205-294.
- Addicott JF, Aho JM, Antolin MF, Padilla DK, Richardson JS, Soluk DA (1987) Ecological neighborhoods: scaling environmental patterns. Oikos 1:340-346.
- Pittman SJ, Davis B, Santos-Corujo RO (2017) Chapter 7: Animal movements through the seascape: Integrating movement ecology with seascape ecology. p189-227. In Pittman SJ (ed.) Seascape Ecology. John Wiley & Sons Ltd.