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1.
Carolyn Harrison Mordechai Haklay 《Journal of Environmental Planning and Management》2002,45(6):841-863
The paper draws on an empirical study of two workshops in which the issues that arise from the use of geographic information systems (GIS) as a planning tool in public participation settings were explored by local residents who take an active interest in local planning matters in their London borough. The paper demonstrates how issues concerned with the democratization of GIS and public participation GIS (PPGIS) informed the structure and conduct of the workshops and the qualitative analysis of the workshop discussions. Key themes raised by participants included: the potential of PPGIS as a means of extending knowledge networks; issues of data ownership and the responsiveness of data providers to public concerns; and the role that institutional norms and practices play in democratizing information availability and the transparency of the decision-making process. The paper concludes that the potential of PPGIS as a planning tool cannot be separated from public concerns about the legitimacy of the planning process or local government. 相似文献
2.
Ed Gidman Royston Goodacre Bridget Emmett Lucy J. Sheppard Ian D. Leith Dylan Gwynn-Jones 《Water, Air, & Soil Pollution: Focus》2004,4(6):251-258
The potential for metabolic fingerprinting via Fourier-transform infrared (FT-IR) spectroscopy to provide a novel approach for the detection of plant biochemical responses to N deposition is examined. An example of spectral analysis using shoot samples taken from an open top chamber (OTC) experiment simulating wet ammonium deposition is given. Sample preparation involved oven drying and homogenisation via mill grinding. Slurries of a consistent dilution were then prepared prior to FT-IR analysis. Spectra from control, 8 and 16 kg N ha–1 yr–1 treatments were then subjected to cross-validated discriminant function analysis. Ordination diagrams showed clear separation between the three N treatments examined. The potential for using Calluna vulgaris (L.) Hull as a bioindicator of N deposition is further evident from these results. The results also clearly demonstrate the power of FT-IR in discriminating between subtle phenotypic alterations in overall plant biochemistry as affected by ammonium pollution. 相似文献
3.
A marked decline in the contribution by Marovo Lagoon to the annual total bêche-de-mer production of the Solomon Islands from
58% in 1989 to 17% in 2003 prompted investigation of their current biomass and diversity. We also assessed changes to critical
ecological services and the prospects for population recovery following a fisheries closure. Day time and nocturnal transects
revealed a mean abundance of 32.4 (SD = 5.3) low value species per ha (e.g. Holothuria atra, H. edulis, H. coluber and Thelenota anax) and 15.2 (SD = 2.7) high value species per ha (e.g. H. fuscogilva, Actinopyga lecanora, Stichopus hermanni and Thelenota ananas). Following a 17 month closure of the fishery (2005–2007), the abundance of bêche-de-mer was reported by local fisherman
to have increased; however, no scientific studies were conducted that can substantiate this community held belief. The current
study aimed to document the impact of re-opening the fishery in 2007 and documented a decline in high value species of 9%
over a 5 month period following the opening of the fishery, while low value species continued to increase in abundance by
11%, over the same period based on nocturnal surveys. Continued observation of the recovery, post closure, and any subsequent
harvest in Marovo will be required to properly understand population dynamics and provide a sustainable harvest plan for bêche-de-mer
in the future. 相似文献
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6.
The local food movement has been touted by some as a profoundly effective way to make our food system become more healthy, just, and sustainable. Others have criticized the movement as being less a challenge to the status quo and more an easily co-opted support offering just another set of choices for affluent consumers. In this paper, we analyze three distinct sub-movements within the local food movement, the individual-focused sub-movement, the systems-focused sub-movement, and the community-focused sub-movement. These movements can be combined within any particular campaign or within the goals of any particular organization or individual activist, but they are nevertheless quite different from each other, and come out of different conceptualizations of what food, people, and locality are. We argue that most of the critiques leveled against local food are actually directed against the individual-focused sub-movement, which is most compatible with the current industrial food system, and perhaps not surprisingly receives the most mainstream attention. Further, we argue that while each movement has its own strengths and weaknesses, it is the community-focused sub-movement that has the most potential to radically transform the global food system. 相似文献
7.
Fabian Engel Kaitlin J. Farrell Ian M. McCullough Facundo Scordo Blaize A. Denfeld Hilary A. Dugan Elvira de Eyto Paul C. Hanson Ryan P. McClure Peeter Nõges Tiina Nõges Elizabeth Ryder Kathleen C. Weathers Gesa A. Weyhenmeyer 《Die Naturwissenschaften》2018,105(3-4):25
The magnitude of lateral dissolved inorganic carbon (DIC) export from terrestrial ecosystems to inland waters strongly influences the estimate of the global terrestrial carbon dioxide (CO2) sink. At present, no reliable number of this export is available, and the few studies estimating the lateral DIC export assume that all lakes on Earth function similarly. However, lakes can function along a continuum from passive carbon transporters (passive open channels) to highly active carbon transformers with efficient in-lake CO2 production and loss. We developed and applied a conceptual model to demonstrate how the assumed function of lakes in carbon cycling can affect calculations of the global lateral DIC export from terrestrial ecosystems to inland waters. Using global data on in-lake CO2 production by mineralization as well as CO2 loss by emission, primary production, and carbonate precipitation in lakes, we estimated that the global lateral DIC export can lie within the range of \( {0.70}_{-0.31}^{+0.27} \) to \( {1.52}_{-0.90}^{+1.09} \) Pg C yr?1 depending on the assumed function of lakes. Thus, the considered lake function has a large effect on the calculated lateral DIC export from terrestrial ecosystems to inland waters. We conclude that more robust estimates of CO2 sinks and sources will require the classification of lakes into their predominant function. This functional lake classification concept becomes particularly important for the estimation of future CO2 sinks and sources, since in-lake carbon transformation is predicted to be altered with climate change. 相似文献
8.
A mother affected with Apert's syndrome was diagnosed by ultrasound scan at 16–17 weeks to have a fetus similarly affected. The typical features of acrocephaly and symmetrical syndactyly were seen. This is probably the first time that this condition has been diagnosed at such a gestation by ultrasound scan. The patient decided to continue the pregnancy, and intrauterine death occurred at 34 weeks. The diagnosis was confirmed by pathological examination. 相似文献
9.
Changes in the saturated uptake kinetics of the limiting nutrient were followed as Thalassiosira pseudonana (Clone 3 H) batch cultures entered ammonium, nitrate, silicate and phosphate starvation. Cultures starved of ammonium or phosphate developed very high specific uptake capacities over a 24 to 48 h starvation period, due to both decreases in cell quota and increases in uptake rates per cell. In particular, the cell phosphorus quota decreased ca. 8-fold during phosphate starvation and specific uptake rates exceeded 100 d-1. In contrast, cultures entering nitrate or silicate starvation underwent little or no further cell division, and the uptake capacity declined during starvation. After 24 to 48 h starvation, an induction requirement for uptake of nitrate or silicate was apparent. These responses are consistent with adaptation to the pattern of supply of these nutrients in the field. 相似文献
10.
The ultrastructure of the genera Althornia, Aplanochytrium, Japonochytrium, Schizochytrium and Thraustochytrium is described, and all are regarded as members of the new order Thraustochytriales Sparrow. Species considered are Althornia crouchii, Aplanochytrium kerguelensis, Hyalochlorella marina, Japonochytrium sp., Schizochytrium aggregatum, Thraustochytrium kinnei and T. striatum. All but H. marina are, on ultrastructural evidence, related genera, and some speculative suggestions are made about possible interrelationships both between the species discussed, between the Thraustochytriales and Labyrinthulales, and between these two and other major taxa. 相似文献