19 resultados para production structure


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This paper takes at its starting point the responsibility placed upon corporations by the United Nations’ Protect, Respect and Remedy Framework as elaborated upon by the Guiding Principles on Business and Human Rights to respect human rights. The overt pragmatism and knowledge of the complex business relationships that are embedded in global production led John Ruggie, the author of the Framework, to adopt a structure for the relationship between human rights and business that built on the existing practices of Corporate Social Responsibility (CSR). His intention was that these practices should be developed to embrace respect for human rights by exhorting corporations to move from “the era of declaratory CSR” to showing a demonstrable policy commitment to respect for human rights. The prime motivation for corporations to do this was, according to Ruggie, because the responsibility to respect was one that would be guarded and judged by the “courts of public opinion” as part of the social expectations imposed upon corporations or to put it another way as a condition of a corporation’s social license to operate.
This article sets out the background context to the Framework and examines the structures that it puts forward. In its third and final section the article looks at how the Framework requires a corporation’s social license to be assembled and how and by whom that social license will be judged. The success or failure of the Framework in persuading corporations to respect human rights is tied to whether “the courts of public opinion” can use their “naming and shaming power” effectively.

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Globally lakes bury and remineralise significant quantities of terrestrial C, and the associated flux of terrestrial C strongly influences their functioning. Changing deposition chemistry, land use and climate induced impacts on hydrology will affect soil biogeochemistry and terrestrial C export1 and hence lake ecology with potential feedbacks for regional and global C cycling. C and nitrogen stable isotope analysis (SIA) has identified the terrestrial subsidy of freshwater food webs. The approach relies on different 13C fractionation in aquatic and terrestrial primary producers, but also that inorganic C demands of aquatic primary producers are partly met by 13C depleted C from respiration of terrestrial C, and ‘old’ C derived from weathering of catchment geology. SIA thus fails to differentiate between the contributions of old and recently fixed terrestrial C. Natural abundance 14C can be used as an additional biomarker to untangle riverine food webs2 where aquatic and terrestrial δ 13C overlap, but may also be valuable for examining the age and origin of C in the lake. Primary production in lakes is based on dissolved inorganic C (DIC). DIC in alkaline lakes is partially derived from weathering of carbonaceous bedrock, a proportion of which is14C-free. The low 14C activity yields an artificial age offset leading samples to appear hundreds to thousands of years older than their actual age. As such, 14C can be used to identify the proportion of autochthonous C in the food-web. With terrestrial C inputs likely to increase, the origin and utilisation of ‘fossil’ or ‘recent’ allochthonous C in the food-web can also be determined. Stable isotopes and 14C were measured for biota, particulate organic matter (POM), DIC and dissolved organic carbon (DOC) from Lough Erne, Northern Ireland, a humic alkaline lake. Temporal and spatial variation was evident in DIC, DOC and POM C isotopes with implications for the fluctuation in terrestrial export processes. Ramped pyrolysis of lake surface sediment indicates the burial of two C components. 14C activity (507 ± 30 BP) of sediment combusted at 400˚C was consistent with algal values and younger than bulk sediment values (1097 ± 30 BP). The sample was subsequently combusted at 850˚C, yielding 14C values (1471 ± 30 BP) older than the bulk sediment age, suggesting that fossil terrestrial carbon is also buried in the sediment. Stable isotopes in the food web indicate that terrestrial organic C is also utilised by lake organisms. High winter δ 15N values in calanoid zooplankton (δ 15N = 24%¸) relative to phytoplankton and POM (δ 15N = 6h and 12h respectively) may reflect several microbial trophic levels between terrestrial C and calanoids. Furthermore winter calanoid 14C ages are consistent with DOC from an inflowing river (75 ± 24 BP), not phytoplankton (367 ± 70 BP). Summer calanoid δ 13C, δ 15N and 14C (345 ± 80 BP) indicate greater reliance on phytoplankton.

1 Monteith, D.T et al., (2007) Dissolved organic carbon trends resulting from changes in atmospheric deposition chemistry. Nature, 450:537-535

2 Caraco, N., et al.,(2010) Millennial-aged organic carbon subsidies to a modern river food web. Ecology,91: 2385-2393.

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Development of green composite from natural fibers has gained increasing interests due to the environmental and sustainable benefits when compared with petroleum based non-degradable materials. However, a big challenge of green composites is the diversity of fiber sources, because of the large variation in the properties and characteristics of the lignocellulosic renewable resource. The lignocellulosic fibers/natural fibers used to reinforce green composites are reviewed in this chapter. A classification of fiber types and sources, the properties of various natural fibers, including structure, composition, physical and chemical properties are focused; followed by the impacts of natural fibers on composite properties, with identification of the main pathways from the natural fibers to the green composite. Furthermore, the main challenges and future trend of natural fibers are highlighted.