Mercer J.,Secure Futures |
Kurvits T.,GRID Arendal |
Kelman I.,University College London |
Kelman I.,Norwegian Institute of International Affairs NUPI |
Mavrogenis S.,Panteion University
Sustainability (Switzerland) | Year: 2014
This paper critically reviews ecosystem-based adaptation (EbA) approaches for food security under climate change, specifically for the Small Island Developing States (SIDS) comprising the Africa, Indian Ocean, Mediterranean and South China Sea (AIMS) region. The focus is on integrating different knowledge forms. An analysis of current EbA approaches for food security is undertaken, alongside a review of methodologies for integrating local and external knowledge. Key gaps and actions for EbA for food security in the AIMS region, and potentially further afield, are identified. The gaps indicate the lack of coherence in AIMS SIDS approaching food security, in terms of policies and actions not reflecting the ecosystem-food-climate nexus, the lack of a regional framework despite similarities amongst the SIDS, and the infrequency with which knowledge integration occurs. To fill these gaps, suggested actions highlight knowledge identification and combination, learning from others and from history, using local champions, and regularly monitoring and evaluating progress. These actions will push forward the EbA agenda through improved development and use of knowledge, better connections amongst the AIMS SIDS and farther afield, and more local-national-regional collaboration. © 2014 by the authors, licensee MDPI, Basel, Switzerland.
Tesi T.,CNR Marine Science Institute |
Tesi T.,Oregon State University |
Goni M.A.,Oregon State University |
Langone L.,CNR Marine Science Institute |
And 11 more authors.
Global Biogeochemical Cycles | Year: 2010
Outcrops of old strata at the shelf edge resulting from erosive gravity-driven flows have been globally described on continental margins. The reexposure of old strata allows for the reintroduction of aged organic carbon (OC), sequestered in marine sediments for thousands of years, into the modern carbon cycle. This pool of reworked material represents an additional source of 14C-depleted organic carbon supplied to the ocean, in parallel with the weathering of fossil organic carbon delivered by rivers from land. To understand the dynamics and implications of this reexposure at the shelf edge, a biogeochemical study was carried out in the Gulf of Lions (Mediterranean Sea) where erosive processes, driven by shelf dense water cascading, are currently shaping the seafloor at the canyon heads. Mooring lines equipped with sediment traps and current meters were deployed during the cascading season in the southwestern canyon heads, whereas sediment cores were collected along the sediment dispersal system from the prodelta regions down to the canyon heads. Evidence from grain-size, X-radiographs and 210Pb activity indicate the presence in the upper slope of a shelly-coarse surface stratum overlying a consolidated deposit. This erosive discontinuity was interpreted as being a result of dense water cascading that is able to generate sufficient shear stress at the canyon heads to mobilize the coarse surface layer, eroding the basal strata. As a result, a pool of aged organic carbon (14C = -944.5 24.7‰; mean age 23,650 3,321 ybp) outcrops at the modern seafloor and is reexposed to the contemporary carbon cycle. This basal deposit was found to have relatively high terrigenous organic carbon (lignin = 1.48 0.14 mg/100 mg OC), suggesting that this material was deposited during the last low sea-level stand. A few sediment trap samples showed anomalously depleted radiocarbon concentrations (14C = -704.4 62.5‰) relative to inner shelf (14C = -293.4 134.0‰), mid-shelf (14C = -366.6 51.1‰), and outer shelf (14C = -384 47.8‰) surface sediments. Therefore, although the major source of particulate material during the cascading season is resuspended shelf deposits, there is evidence that this aged pool of organic carbon can be eroded and laterally advected downslope. © 2010 by the American Geophysical Union.
Huang Z.,Geoscience Australia |
Nichol S.L.,Geoscience Australia |
Harris P.T.,GRID Arendal |
Caley M.J.,Australian Institute of Marine Science
Marine Geology | Year: 2014
Submarine canyons influence oceanographic processes, sediment transport, productivity and benthic biodiversity from the continental shelf to the slope and beyond. However, not all canyons perform the same function. The relative influence of an individual canyon on these processes will, in part, be determined by its form, shape and position on the continental margin. Here we present an analysis of canyon geomorphic metrics using an updated national dataset of 713 submarine canyons surrounding mainland Australia. These metrics (attributes) for each canyon are used to classify them into canyon types across a hierarchy of physical characteristics separately for shelf-incising (n. =. 95) and slope-confined (blind; n. =. 618) canyons. We find that the canyon metrics describe a wide variety of canyon form and complexity that is consistent with a population of canyons that has evolved at different rates around the Australian margin since the break-up of Gondwana. The large number of slope-confined canyons is interpreted to reflect dominance of slope mass-wasting processes over erosive turbidity flows from fluvial and shelf sources on an arid continent. The distribution of submarine canyons around the Australian margin is not regular, with clusters occurring in the east, southeast, west and southwest where the margin is steepest. The classification result provides a quantitative framework for describing canyon heterogeneity for application in studies of geological controls on individual canyons, canyon oceanography and canyon biodiversity. © 2014 Published by Elsevier B.V.
Langenheim V.E.,U.S. Geological Survey |
Wright T.L.,Chevron |
Okaya D.A.,University of Southern California |
Yeats R.S.,Oregon State University |
And 3 more authors.
Geosphere | Year: 2011
Industry seismic reflection data, oil test well data, interpretation of gravity and magnetic data, and seismic refraction deep-crustal profiles provide new perspectives on the subsurface geology of San Fernando Valley, home of two of the most recent damaging earthquakes in southern California. Seismic reflection data provide depths to Miocene-Quaternary horizons; beneath the base of the Late Miocene Modelo Formation are largely nonreflective rocks of the Middle Miocene Topanga and older formations. Gravity and seismic reflection data reveal the North Leadwell fault zone, a set of down-to-the-north faults that does not offset the top of the Modelo Formation; the zone strikes northwest across the valley, and may be part of the Oak Ridge fault system to the west. In the southeast part of the valley, the fault zone bounds a concealed basement high that influenced deposition of the Late Miocene Tarzana fan and may have localized damage from the 1994 Northridge earthquake. Gravity and seismic refraction data indicate that the basin underlying San Fernando Valley is asymmetric, the north part of the basin (Sylmar subbasin) reaching depths of 5-8 km. Magnetic data suggest a major boundary at or near the Verdugo fault, which likely started as a Miocene transtensional fault, and show a change in the dip sense of the fault along strike. The northwest projection of the Verdugo fault separates the Sylmar subbasin from the main San Fernando Valley and coincides with the abrupt change in structural style from the Santa Susana fault to the Sierra Madre fault. The Simi Hills bound the basin on the west and, as defined by gravity data, the boundary is linear and strikes ~N45°E. That northeast-trending gravity gradient follows both the part of the 1971 San Fernando aftershock distribution called the Chatsworth trend and the aftershock trends of the 1994 Northridge earthquake. These data suggest that the 1971 San Fernando and 1994 Northridge earthquakes reactivated portions of Miocene normal faults. © 2011 Geological Society of America.
Harris P.T.,Geoscience Australia |
Macmillan-Lawler M.,GRID Arendal |
Rupp J.,Wildlife Conservation Society |
Baker E.K.,University of Sydney
Marine Geology | Year: 2014
We present the first digital seafloor geomorphic features map (GSFM) of the global ocean. The GSFM includes 131,192 separate polygons in 29 geomorphic feature categories, used here to assess differences between passive and active continental margins as well as between 8 major ocean regions (the Arctic, Indian, North Atlantic, North Pacific, South Atlantic, South Pacific and the Southern Oceans and the Mediterranean and Black Seas). The GSFM provides quantitative assessments of differences between passive and active margins: continental shelf width of passive margins (88km) is nearly three times that of active margins (31km); the average width of active slopes (36km) is less than the average width of passive margin slopes (46km); active margin slopes contain an area of 3.4millionkm2 where the gradient exceeds 5°, compared with 1.3millionkm2 on passive margin slopes; the continental rise covers 27millionkm2 adjacent to passive margins and less than 2.3millionkm2 adjacent to active margins. Examples of specific applications of the GSFM are presented to show that: 1) larger rift valley segments are generally associated with slow-spreading rates and smaller rift valley segments are associated with fast spreading; 2) polar submarine canyons are twice the average size of non-polar canyons and abyssal polar regions exhibit lower seafloor roughness than non-polar regions, expressed as spatially extensive fan, rise and abyssal plain sediment deposits - all of which are attributed here to the effects of continental glaciations; and 3) recognition of seamounts as a separate category of feature from ridges results in a lower estimate of seamount number compared with estimates of previous workers. © 2014.
Ebbinge B.S.,Wageningen University |
Prokosch P.,GRID Arendal |
Spaans B.,Netherlands Institute for Sea Research |
Muskens G.J.D.M.,Wageningen University |
And 3 more authors.
Wildfowl | Year: 2013
The distribution of Dark-bellied Brent Geese Branta b. bernicla moulting on the Taimyr Peninsula, in the Russian arctic, varies between years depending on whether the birds had a successful breeding season. Counts made of moulting flocks show that major shifts in numbers occur, particularly in non-breeding years, when in line with Salomonsen's (1968) hypothesis a higher proportion of the population moults further north. For instance, the delta of the Lower Taimyr River in the northern part of the Taimyr Peninsula held 10-times more moulting Dark-bellied Brent Geese in 1989, a non-breeding year, than it did in the good 1990 breeding season. At a more local scale, in good breeding years family groups with small goslings tend to move away from breeding islands in the Pyasina Delta, western Taimyr, to avoid gosling predation by Taimyr Gulls Larus taimyrensis which nest in colonies on the same islands, whereas in poor breeding years adult geese concentrate on these same islands to moult and avoid the mainland sites used for moulting in good breeding years. Failed breeders have greater freedom than parent birds to choose where to moult as successful breeders remain with their goslings to protect and guide them to the safest nursery and moult areas. Re-captures of ringed Darkbellied Brent Geese at a moulting site in the Pyasina Delta found that, in poor breeding years, up to one-fifth the birds had moulted at the site previously, but that the majority of ringed birds known to be still alive were not site-faithful to their moulting grounds. © Wildfowl and Wetlands Trust.
Comberti C.,University of Oxford |
Thornton T.F.,University of Oxford |
Wylliede Echeverria V.,University of Oxford |
Patterson T.,GRID Arendal
Global Environmental Change | Year: 2015
The concept of Ecosystem Services (ES), widely understood as the "benefits that humans receive from the natural functioning of healthy ecosystems" (. Jeffers et al., 2015), depicts a one-way flow of services from ecosystems to people. We argue that this conceptualisation is overly simplistic and largely inaccurate, neglecting the reality that humans often contribute to the maintenance and enhancement of ecosystems, as often evidenced (but not exclusively) in many traditional and Indigenous societies. Management interventions arising from Ecosystem Services research are thus potentially damaging to both ecosystems and indigenous rights. We present the concept of 'Services to Ecosystems' (S2E) to address this, closing the loop of the reciprocal relationship between humans and ecosystems. Case studies from the biocultural ecosystems of Amazonia and the Pacific Northwest of North America (Cascadia) are used to illustrate the concept and provide examples of Services to Ecosystems in past and current societies. Finally, an alternative framework is presented, advancing the existing framework for Ecosystem Services by incorporating this reconceptualization and the loop of reciprocity. The framework aims to facilitate the inclusion of Services to Ecosystems in management strategies based upon Ecosystem Services, and highlights the need for ethnographic research in Ecosystem Service-based interventions. © 2015 Z.
van Oort B.,CICERO Center for International Climate and Environmental Research |
Bhatta L.D.,International Center for Integrated Mountain Development |
Baral H.,Center for International Forestry Research |
Dhakal M.,International Center for Integrated Mountain Development |
And 2 more authors.
Ecosystem Services | Year: 2015
Human activities and climate change are key factors impacting ecosystem functions and its goods and services, which are important to the livelihoods of mountain communities. In Nepal, community based ecosystem management has been widely adopted as a way to secure local management and empowerment, but local knowledge, perceptions and values of ecosystem change and services are often ignored, and perhaps inadequately understood, in decision-making processes at district or national level. Our objective therefore was to develop a multi-method approach to support mapping of ecosystem services and assessing their local values. Local perceptions of ecosystem use, change and values were identified using participatory mapping, key informant and focus group discussions, and an extensive household survey carried out in the upstream Koshi River basin. Results were cross-validated with scientific literature, statistics and remote sensing data. Key ecosystem services identified are water, agricultural produce, and various forest products, most of which show a declining trend. We demonstrate that the use of different methods and levels of input results in different and complementary types of insights and detail needed for balanced and informed decision-making regarding sustainable management of ESs to secure current and future livelihoods and ecosystem functioning. © 2014 Elsevier B.V.