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
Global patterns in species richness in sandy beach ecosystems have been poorly understood until comparatively recently, because of the difficulty of compiling high-resolution databases at continental ...scales. We analyze information from more than 200 sandy beaches around the world, which harbor hundreds of macrofauna species, and explore latitudinal trends in species richness, abundance and biomass. Species richness increases from temperate to tropical sites. Abundance follows contrasting trends depending on the slope of the beach: in gentle slope beaches, it is higher at temperate sites, whereas in steep-slope beaches it is higher at the tropics. Biomass follows identical negative trends for both climatic regions at the whole range of beach slopes, suggesting decreasing rates in carrying capacity of the environment towards reflective beaches. Various morphodynamic variables determine global trends in beach macrofauna. Species richness, abundance and biomass are higher at dissipative than at reflective beaches, whereas a body size follows the reverse pattern. A generalized linear model showed that large tidal range (which determines the vertical dimension of the intertidal habitat), small size of sand particles and flat beach slope (a product of the interaction among wave energy, tidal range and grain size) are correlated with high species richness, suggesting that these parameters represent the most parsimonious variables for modelling patterns in sandy beach macrofauna. Large-scale patterns indicate a scaling of abundance to a body size, suggesting that dissipative beaches harbor communities with highest abundance and species with the smallest body sizes. Additional information for tropical and northern hemisphere sandy beaches (underrepresented in our compilation) is required to decipher more conclusive trends, particularly in abundance, biomass and body size. Further research should integrate meaningful oceanographic variables, such as temperature and primary production, in deciphering latitudinal trends.
•We explore worldwide patterns in species richness and abundance in sandy beaches.•Species richness increases from temperate to tropical sandy beaches.•Abundance, biomass and body size show less conclusive latitudinal patterns.•Species richness, abundance and biomass increase with tide range and at flat beaches.•A body size follows a reverse trend, suggesting scaling of abundance to a body size.
Threats to sandy beach ecosystems: A review Defeo, Omar; McLachlan, Anton; Schoeman, David S. ...
Estuarine, coastal and shelf science,
2009, 2009-1-00, 20090101, Letnik:
81, Številka:
1
Journal Article
Recenzirano
We provide a brief synopsis of the unique physical and ecological attributes of sandy beach ecosystems and review the main anthropogenic pressures acting on the world's single largest type of open ...shoreline. Threats to beaches arise from a range of stressors which span a spectrum of impact scales from localised effects (e.g. trampling) to a truly global reach (e.g. sea-level rise). These pressures act at multiple temporal and spatial scales, translating into ecological impacts that are manifested across several dimensions in time and space so that today almost every beach on every coastline is threatened by human activities. Press disturbances (whatever the impact source involved) are becoming increasingly common, operating on time scales of years to decades. However, long-term data sets that describe either the natural dynamics of beach systems or the human impacts on beaches are scarce and fragmentary. A top priority is to implement long-term field experiments and monitoring programmes that quantify the dynamics of key ecological attributes on sandy beaches. Because of the inertia associated with global climate change and human population growth, no realistic management scenario will alleviate these threats in the short term. The immediate priority is to avoid further development of coastal areas likely to be directly impacted by retreating shorelines. There is also scope for improvement in experimental design to better distinguish natural variability from anthropogenic impacts. Sea-level rise and other effects of global warming are expected to intensify other anthropogenic pressures, and could cause unprecedented ecological impacts. The definition of the relevant scales of analysis, which will vary according to the magnitude of the impact and the organisational level under analysis, and the recognition of a physical–biological coupling at different scales, should be included in approaches to quantify impacts. Zoning strategies and marine reserves, which have not been widely implemented in sandy beaches, could be a key tool for biodiversity conservation and should also facilitate spillover effects into adjacent beach habitats. Setback and zoning strategies need to be enforced through legislation, and all relevant stakeholders should be included in the design, implementation and institutionalisation of these initiatives. New perspectives for rational management of sandy beaches require paradigm shifts, by including not only basic ecosystem principles, but also incentives for effective governance and sharing of management roles between government and local stakeholders.
The data from 161 quantitative sandy beach transect surveys from a wide variety of locations were examined to identify trends and relationships between total marine macrofauna species richness, ...abundance, and biomass and physical variables. Several physical variables were correlated, especially sand particle size and beach face slope, and spring tide range and beach face slope. Higher latitudes experienced larger waves, and flatter beaches had finer sands, larger waves, and larger tides. Strong correlations were found between species richness and beach slope, tide range, and sand particle size, as well as various indices of beach state. Tropical regions harbored significantly more species than other regions. A new Beach index (BI), based on tide range, beach face slope, and sand particle size, correlated well with species richness, explaining 56% of the variability in the data without considering latitude. Abundance and biomass were best correlated with log(1/beach face slope) and tended to be higher in temperate regions. General patterns are discussed; the new index is evaluated; and the roles of sand, tide, slope, and latitude are considered. It is concluded that for regional studies log(1/beach face slope) is the most useful index to compare beaches, whereas for wider comparisons covering areas of differing tide range, BI might be most useful. These patterns have implications for global biodiversity management on sandy beaches.
Escalating pressures caused by the combined effects of population growth, demographic shifts, economic development and global climate change pose unprecedented threats to sandy beach ecosystems ...worldwide. Conservation of beaches as functional ecosystems and protection of their unique biodiversity requires management interventions that not only mitigate threats to physical properties of sandy shores, but also include ecological dimensions. Yet, beach management remains overwhelmingly focused on engineering interventions. Here we summarise the key outcomes of several workshops, held during the 2006 Sandy Beach Ecology Symposium in Vigo, Spain, that addressed issues of climate change, beach management and sampling methodology. Because efficient communication between managers and ecologists is critical, we summarise the salient features of sandy beaches as functional ecosystems in 50 ‘key statements’; these provide a succinct synopsis of the main structural and functional characteristics of these highly dynamic systems. Key outcomes of the workshops include a set of recommendations on designs and methods for sampling the benthic infaunal communities of beaches, the identification of the main ecological effects caused by direct and indirect human interventions, the predicted consequence of climate change for beach ecosystems, and priority areas for future research.
Sandy beaches at the brink Schlacher, Thomas A.; Dugan, Jenifer; Schoeman, Dave S. ...
Diversity & distributions,
September 2007, Letnik:
13, Številka:
5
Journal Article
Recenzirano
Odprti dostop
Sandy beaches line most of the world's oceans and are highly valued by society: more people use sandy beaches than any other type of shore. While the economic and social values of beaches are ...generally regarded as paramount, sandy shores also have special ecological features and contain a distinctive biodiversity that is generally not recognized. These unique ecosystems are facing escalating anthropogenic pressures, chiefly from rapacious coastal development, direct human uses - mainly associated with recreation - and rising sea levels. Beaches are increasingly becoming trapped in a 'coastal squeeze' between burgeoning human populations from the land and the effects of global climate change from the sea. Society's interventions (e.g. shoreline armouring, beach nourishment) to combat changes in beach environments, such as erosion and shoreline retreat, can result in severe ecological impacts and loss of biodiversity at local scales, but are predicted also to have cumulative large-scale consequences worldwide. Because of the scale of this problem, the continued existence of beaches as functional ecosystems is likely to depend on direct conservation efforts. Conservation, in turn, will have to increasingly draw on a consolidated body of ecological theory for these ecosystems. Although this body of theory has yet to be fully developed, we identify here a number of critical research directions that are required to progress coastal management and conservation of sandy beach ecosystems.
The sandy beaches that fringe much of the world's oceans are the most sought-after venue for recreation and tourism on our home planet. However, the value of sandy shores goes well beyond simple ...recreation, fun and enjoyment. The social-ecological system comprising the sandy littoral zone has diverse intrinsic values, not just in ecosystem services and as repositories of biodiversity, but also as part of our spiritual and cultural world. In this essay we aim to highlight the inherent beauty of sandy littoral zones as a whole and beaches in particular, through the eyes of celebrated poets. We explore the timeless fascination that beaches have held for people and their immense value in spiritual, cultural, economic and environmental contexts. We touch briefly on how beaches are threatened today by a variety of stressors, which are driven primarily by anthropogenic influences. We draw attention to the requirement to consider the sandy littoral holistically and include the beach, dunes and surf zone, which are tightly coupled systems. Then we conclude by emphasising the need for farsighted and participatory governance that should manage the entire sandy littoral as a whole and be underpinned by sound science. We hope that this essay will promote greater appreciation of sandy beaches and stimulate research focused on providing direction to coastal planning and management, as well as encouraging custodians of the coast to consider a more participatory approach to governance.
Display omitted
•Sandy beaches hold a timeless fascination and are the most sought-after recreation venue on our planet.•Beaches provide several ecosystem services to people over and above recreation.•Beaches face coastal squeeze, being constricted between rising sea level and encroaching development.•The future of these ecosystems depends on adaptive and participatory governance based on sound science.
Beach erosion is a complex process influenced by multiple factors operating at different spatial scales. Local (e.g., waves, tides, grain size, beach width and coastal development) and regional ...(e.g., sea level rise and mean sea level pressure) factors both shape erosion processes. A comprehensive understanding of how these drivers collectively impact sandy beach erosion is needed. To address this on a global-scale we assembled a database with
in-situ
information on key physical variables from 315 sandy beaches covering a wide morphodynamic range and complemented by satellite data on regional variables. Our results revealed the combined influence of local and regional factors on beach erosion rates. Primary drivers were regional anomalies in mean sea level pressure and variations in mean sea level, and local factors such as tide range, beach slope and width, and Dean’s parameter. By analyzing morphodynamic characteristics, we identified five distinct clusters of sandy beaches ranging from wave-dominated microtidal reflective beaches to tide-modified ultradissipative beaches. This energy dissipation gradient emerged as a critical factor, with erosion rates increasing with beach width and dissipativeness. Our study also highlighted the tangible impact of climate change on beach erosion patterns. Hotspots were identified, where intensification of regional anomalies in mean sea level pressure, increasing onshore winds and warming rates, and rising sea levels synergistically accelerated erosion rates. However, local variables were found to either amplify the effects of regional factors on erosion or enhance a beach’s resistance, mitigating erosive trends initiated by regional drivers. Our analysis showed that more than one-fifth of the analyzed beaches are experiencing intense, extreme, or severe erosion rates, and highlighted the significant role of human activities in explaining erosion trends, particularly in microtidal reflective and intermediate beaches. This underscores the long-term threat of coastal squeeze faced by sandy beaches worldwide and emphasizes the need to consider both local and regional drivers in order to understand erosion processes. Integrating localized measurements with broader satellite observations is required for a comprehensive understanding of the main drivers behind coastal evolution, which in turn is needed to manage and preserve these fragile ecosystems that are at risk.
PDF
