Moveable feast: The incredible journeys of the things we eat     

Peter Perry 《New Zealand geographer》2008,64(1):88-89

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Introduction: Coping with global change in marine social-ecological systems     

R. Ian Perry  Rosemary E. Ommer 《Marine Policy》2010

Marine social-ecological systems are complex, inter-connected, and highly dynamic, in particular when forced with global changes. However, their human social components are often treated separately from their biophysical components, and by different scientific disciplines. To help bridge these gaps, and to explore conceptual, comparative, and governance issues relating to marine social-ecological systems and global change, an international symposium was held on “Coping with global change in marine social-ecological systems”. This short paper provides an introduction to this topic, and briefly describes nine papers which arose from this symposium and which comprise this special issue of Marine Policy. It is concluded that good progress is being made towards studying marine social and ecological systems as coupled systems, but that many issues remain to challenge natural scientists, social scientists, and humanists to work together. These include incorporating multi-stakeholder participation, the need for a long-term perspective, and development of flexible livelihood and governance strategies.  相似文献   

To what extent do improved irrigation technologies extend aquifer life?     

C. J. Perry  P. J. G. J. Hellegers 《Hydrogeology Journal》2012,20(5):907-913

World financial support for Yemen has concentrated on improved irrigation technology as the primary means to reduce the rate of overexploitation of Yemen’s aquifers. An analysis of the impact of such investments on cumulative water abstraction, water savings and the life of an aquifer is presented. It shows that these investments have limited potential to extend aquifer life. The returns are highest in areas with significant remaining resources, and are not attractive in the most severely stressed areas. The analysis also shows that improved irrigation technologies increase the profitability of pumping for the farmer, exacerbating problems of over-abstraction. Finally, it shows that water savings depend on the hydrogeological situation. The policy implications of these findings are discussed in relation to Yemen, an exceptionally water-short country where most of the aquifers in groundwater-irrigated areas are severely over-drafted.  相似文献   

Radius and limb topography of Mercury obtained from images acquired during the MESSENGER flybys     

Jürgen Oberst  Stephan Elgner  F. Scott Turner  Mark E. Perry  Robert W. Gaskell  Maria T. Zuber  Mark S. Robinson  Sean C. Solomon 《Planetary and Space Science》2011,59(15):1918-1924

Analysis of images obtained by the MESSENGER spacecraft during its three flybys of Mercury yields a new estimate for the planet's mean radius of 2439.25±0.69 km, in agreement with results from Mariner 10 and Earth-based observations, as well as with MESSENGER altimeter and occultation data. The mean equatorial radius and polar radius are identical to within error, suggesting that rotational oblateness is negligible when compared with other sources of topography. This result is consistent with the small gravitational oblateness of the planet. Minor differences in radius obtained at different locations reflect regional variations in topography. Residual topography along three limb profiles has a dynamic range of 7.4 km and a root-mean-square roughness of 0.8 km over hemispherical scales. Following MESSENGER's entry into orbit about Mercury in March 2011, we expect considerable additional improvements to our knowledge of Mercury's size and shape.  相似文献   

Chemical element concentrations in black locust (<Emphasis Type="Italic">Robinia pseudoacacia</Emphasis> L.) and green ash (<Emphasis Type="Italic">Fraxinus pennsylvanica</Emphasis> Marsh.) leaves at the reclaimed Green Valley coal Mine,Indiana, USA     

Ryan R. Jensen  Sandra S. Brake  Stephen F. Wolf  Matthew F. Bekker  Perry James Hardin  Mark W. Jackson 《Environmental Earth Sciences》2010,60(7):1391-1405

The Green Valley Mine in Indiana was abandoned in 1963 after 15 years of coal mining. Reclamation began in 1994 and ended in 1999 with the dense planting of twelve different tree species. By 2006, only green ash (Fraxinus pennsylvanica Marsh.) and black locust (Robinia pseudoacacia L.) had survived in any significant numbers. Given the acid mine drainage found at the site, we sought to determine whether element toxicity originating from mine waste was responsible for the extirpation of the trees. Leaf samples taken from 125 mine trees and 29 control trees were acquired and assayed for 41 element concentrations using inductively coupled plasma mass spectrometry (ICPMS). Except for sodium, there was no compelling evidence to indicate that toxic elemental levels were responsible for the widespread tree deaths. In addition to sodium toxicity, we suspect that micronutrient deficiency was a primary factor explaining the extirpation of trees at the mine.  相似文献   

Intertidal substrate modification as a result of mangrove planting: Impacts of introduced mangrove species on sediment microfacies characteristics     

Christopher T. Perry  Andrew Berkeley 《Estuarine, Coastal and Shelf Science》2009

A programme of mangrove planting has been undertaken around the island of Rodrigues (SW Indian Ocean) since the mid-1980’s involving the introduction of the species Rhizophora mucronata. We examined three coastal embayment sites (Baie Diamant, Anse Goeland and Anse Pansia) in which planting has been undertaken over different time periods within the past 20 years. Planting has met with variable success in the different sites, probably due to variations in fluvial and groundwater influence. At two sites (Baie Diamant – first planted in 1990, and Anse Pansia – first planted in 1995) ecological data indicates that the mangroves are becoming well-established, and sedimentary evidence suggests that relatively rapid modification of intertidal substrates has occurred. This is evident in the form of significant increases in sediment organic-matter content (especially fibrous organic-matter) and an increase in the accumulation of sediment fines inside the mangroves. A strong correlation exists between the magnitude and depth of substrate modification and mangrove forest density, especially root and sapling density. At the third site, Anse Goeland (first planted in 2001), mangrove establishment has not been successful, many of the seedlings have died and no secondary colonisation has occurred. Sediment substrates show no deviation from background levels in terms of organic content or weight % fines content, and we find no evidence for mangrove planting influencing sediment substrates. Despite evidence for the development of a distinctive mangrove facies at Baie Diamant and Anse Pansia there is, however, no evidence as yet for a marked change in substrate geochemistry such as would be demonstrated by evidence of active bioclast dissolution – a common process in many natural (mature) mangrove substrates. We infer this to be a function of the present relative immaturity of the still developing mangrove substrates, but may also be a function of the apparent paucity of burrowing crabs which play an important role in nutrient cycling and sediment geochemistry. Thus whilst the mangroves in some of the study sites are reaching a stage where they are producing distinctive sedimentary facies, the systems appear to be in a state of progressive sedimentary and diagenetic modification as the floral and infaunal components of the mangroves continue to develop.  相似文献   

Upper-mantle thermochemical structure below North America from seismic–geodynamic flow models     

H. K. C. Perry  A. M. Forte  D. W. S. Eaton 《Geophysical Journal International》2003,154(2):279-299

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Belgium by raymond folkextone: Drawson (studies in industrial Geography)     

P.J. Perry 《New Zealand geographer》1977,33(1):45-45

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How societal expectations,new digital tools,and the COVID crisis are driving a step-change in human centric remediation     

John Horst  Carly Foster  Steven Perry  Ajani Stewart  Megan Klar  Beto Altamirano  Prasoon Sinha 《Ground Water Monitoring & Remediation》2021,41(3):13-21

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The significant role of sediment bio-retexturing within a contemporary carbonate platform system: Implications for carbonate microfacies development     

Michael J. O'Leary  Christopher T. Perry  Simon J. Beavington-Penney  John R. Turner 《Sedimentary Geology》2009,219(1-4):169-179

Assessments of carbonate platform reef–lagoon sediments and benthic habitats around Rodrigues Island (south-west Indian Ocean) have been undertaken in order to examine carbonate sediment textural properties and the controls on texturally-defined sediment fabrics. Reef–lagoon sediments, sampled from across the expansive (~ 8 km wide) carbonate-dominated windward platform, principally comprise poorly sorted medium- to coarse-grained bioclastic sands, composed of a low diversity of grain constituents — predominantly non-geniculate coralline algal bioclasts. Despite a marked homogeneity in sediment compositional and grain size properties, eight distinct sediment textural groups can be identified that form a heterogeneous mosaic across the contemporary reef–lagoon system. Only along the narrow outer platform margins (reef crest, sand apron and outermost lagoon environments) do we observe consistent (predictable) transitions in sediment textural groups, where physical processes are the primary drivers of selective sediment transport and sorting. In contrast, across the main expanse of the lagoon, the sediment substrates are characterised by an irregular mosaic of texturally-defined sediment groups — formed primarily as a function of sediment bio-retexturing. The burrowing activities of alpheid and callianassid shrimps are particularly important in this respect and impart a distinctly unique textural fabric to the upper sediment horizons in the environments in which the respective organisms occur. The consequence of this is that, at the platform system scale, individual, texturally-defined sediment groups are relatively poor indicators of prevailing hydrodynamic regimes or of local sediment production, reflecting more the biological action of organisms inhabiting the substrate. This has important implications for understanding the development of carbonate sediment fabrics in the context of palaeoenvironmental reconstructions and for interpreting a key diagnostic criteria of carbonate microfacies.  相似文献