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1.
Emmanuel Kumi Albert A. Arhin Thomas Yeboah 《Environment, Development and Sustainability》2014,16(3):539-554
The Rio+20 summit of the United Nations in Brazil in 2012 committed governments to formulate a set of sustainable development goals (SDGs) that would be integrated into the Millennium Development Goals (MDGs) following its expiration in 2015. This decision has pushed sustainable development agenda into the limelight of development once again. Meanwhile, we note that the development agenda of many developing countries has been dominated by neoliberal orientation driven by market reforms, social inequality, and a move towards enhancing the economic competitiveness of the supply side of the economy. In this paper, we discuss the relationship between neoliberal economic agenda and sustainable development. We do so by examining how neoliberal policies of privatisation, trade liberalisation and reduction in governments spending stand to affect the attainment of sustainable development ideals and their implications on the post-2015 Sustainable Development Goals. The paper then suggests that relying solely on the mechanisms of the market in governing and allocating environmental resources is necessarily insufficient and problematic and therefore calls for a new approach—one which goes beyond just recognising the interdependency among social, environmental and economic goals and places issues of equity and addressing unfavourable power relations at the centre of interventions aimed at achieving the ideals of sustainable development. 相似文献
2.
Daniel Scott Taira Hidaka Pablo Campo Eric Kleiner Makram T. Suidan Albert D. Venosa 《Chemosphere》2013,90(4):1412-1418
A novel membrane system, the Biomass Concentrator Reactor (BCR), was evaluated as an alternative technology for the treatment of municipal wastewater. Because the BCR is equipped with a membrane whose average poresize is 20 μm (18–28 μm), the reactor requires low-pressure differential to operate (gravity). The effectiveness of this system was evaluated for the removal of carbon and nitrogen using two identical BCRs, identified as conventional and hybrid, that were operated in parallel. The conventional reactor was operated under full aerobic conditions (i.e., organic carbon and ammonia oxidation), while the hybrid reactor incorporated an anoxic zone for nitrate reduction as well as an aerobic zone for organic carbon and ammonia oxidation. Both reactors were fed synthetic wastewater at a flow rate of 71 L d?1, which resulted in a hydraulic retention time of 9 h. In the case of the hybrid reactor, the recycle flow from the aerobic zone to the anoxic zone was twice the feed flow rate. Reactor performance was evaluated under two solids retention times (6 and 15 d). Under these conditions, the BCRs achieved nearly 100% mixed liquor solids separation with a hydraulic head differential of less than 2.5 cm. The COD removal efficiency was over 90%. Essentially complete nitrification was achieved in both systems, and nitrogen removal in the hybrid reactor was close to the expected value (67%). 相似文献
3.
The photocatalytic oxidation of oxalyldihydrazide, N,N'-bis(hydrazocarbonyl)hydrazide, N,N'-bis(ethoxycarbonyl)hydrazide, malonyldihydrazide, N-malonyl-bis[(N'-ethoxycarbonyl)hydrazide] was examined in aqueous TiO2 dispersions under UV illumination. The photomineralization of nitrogen and carbon atoms in the substrates into N2 gas, NH4+ (and/or NO3-) ions, and CO2 gas was determined by HPLC and GC analysis. The formation of carboxylic acid intermediates also occurred in the photooxidation process. The photocatalytic mechanism is discussed on the basis of the experimental results, and with molecular orbital (MO) simulation of frontier electron density and point charge. Substrate carbonyl groups readily adsorb on the TiO2 surface, and the bonds between carbonyl group carbon atoms and adjacent hydrazo group nitrogen atoms are cleaved predominantly in the initial photooxidation process. The hydrazo groups were photoconverted mainly into N2 gas (in mineralization yields above 70%) and partially to NH4 ions (below 10%). The formation of NO3- ions was scarcely recognized. 相似文献
4.
Subramanian AN Tanabe S Tanaka H Hidaka H Tatsukawa R 《Environmental pollution (Barking, Essex : 1987)》1987,43(1):39-46
The gain and loss rates and the biological half-life of polychlorinated biphenyls (PCBs) and p,p'-DDE in wild birds were calculated using the values on burdens of these compounds in the bodies of adelie penguins in a previous report (Subramanian et al., 1986). The daily loss rate of PCBs (0.26%) was found to be higher than DDT compounds (0.12%) resulting in the longer biological half-life of the latter compounds (580 days) than PCBs (270 days). Hence, once DDT compounds are absorbed they are more persistent in the organisms' bodies due to their high lipophilicity and comparatively less metabolisable nature than PCBs. 相似文献
5.
Lead poisoning of waterfowl from direct ingestion of wetland mine tailings has been reported at the Coeur d'Alene River basin in Idaho. A greenhouse study was conducted to evaluate the effects of surface applications of amendments on lead bioavailability in the tailings. Treatments included sediment only, and sediment with three different surface amendments: (i) biosolids compost plus wood ash, (ii) compost + wood ash + a low SO4(2-) addition as K2SO4, and (iii) compost + wood ash + a high SO4(2-) addition. Measured variables included growth and tissue Pb, Zn, and Cd concentration of arrowhead (Sagittaria latifolia Willd.) and cattail (Typha latifolia L.) and soil pH, redox potential (Eh), pore water Pb, Pb speciation by X-ray absorption spectroscopy, and in vitro Pb bioavailability. The compost + ash amendment alleviated phytotoxicity for both plant species. Bioavailability of Pb as measured by a rapid in vitro extract decreased by 24 to 34% (over control) in the tailings directly below the amendment layer in the compost + SO4 treatments. The ratio of acid volatile sulfide (AVS) to simultaneously extracted metals (SEM) also indicated a reduction in Pb bioavailability (1:40 control, 1:20 compost, 1:8 compost + low SO4, and 1:3 compost + high SO4). Extended X-ray adsorption fine structure (EXAFS) and X-ray absorption near edge structure (XANES) spectroscopy data indicated that lead sulfide was greater after 99 d in the treatments that included additions of sulfate. These results indicated that, under reducing conditions, surface amendments of compost + wood ash (with or without sulfate) decreased the bioavailability of Pb in metal-contaminated mine tailings. 相似文献
6.
Saki Harii Naoko Yasuda Mauricio Rodriguez-Lanetty Takahiro Irie Michio Hidaka 《Marine Biology》2009,156(6):1203-1212
The establishment of symbiosis in early developmental stages is important for reef-building corals because of the need for
photosynthetically derived nutrition. Corals spawn eggs and sperm, or brood planula larvae and shed them into the water. Some
coral eggs or planulae directly inherit symbiotic dinoflagellates (Symbiodinium spp.) from their parents, while others acquire them at each generation. In most species examined to date, the larvae without
dinoflagellates (aposymbiotic larvae) can acquire symbionts during the larval stage, but little is known regarding the timing
and detailed process of the onset of symbiosis. We examined larval uptake of symbiotic dinoflagellates in nine species of
scleractinian corals, the onset of symbiosis through the early larval stages, and the distribution pattern of symbionts within
the larval host, while living and with histology, of two acroporid corals under laboratory conditions. The larvae acquired
symbiotic dinoflagellates during the planktonic phase in all corals examined which included Acropora digitifera, A. florida, A. intermedia, A. tenuis, Isopora
palifera, Favia pallida, F. lizardensis, Pseudosiderastrea tayamai, and Ctenactis echinata. The larvae of A. digitifera and A. tenuis first acquired symbionts 6 and 5 days after fertilization, respectively. In A. digitifera larvae, this coincided with the formation of an oral pore and coelenteron. The number of symbiotic dinoflagellates increased
over the experimental periods in both species. To test the hypothesis that nutrients promotes symbiotic uptake, the number
of incorporated dinoflagellates was compared in the presence and absence of homogenized Artemia sp. A likelihood ratio test assuming a log-linear model indicated that Artemia sp. had a significantly positive effect on symbiont acquisition. These results suggest that the acquisition of symbiotic
dinoflagellates during larval stages is in common with many coral species, and that the development of both a mouth and coelenteron
play important roles in symbiont acquisition. 相似文献
7.
The existence of “free-living” Symbiodinium that can form symbioses with hosts is implied by the presence of hosts that produce Symbiodinium-free gametes and expulsion and/or expelled symbiotic algae from host. However, it is still unclear if potentially symbiotic
Symbiodinium are found “free-living” in the coral reef environment. Sixteen Symbiodinium strains were established from samples taken from three sampling locations of coral reef sand in Okinawa, Japan. Phylogenetic
analyses of the partial large subunit ribosomal DNA (28S-rDNA) and the internal transcribed spacer of ribosomal DNA (ITS-rDNA)
conclusively showed that all 16 isolates belonged to Symbiodinium clade A sensu Rowan and Powers (1991). The lack of other Symbiodinium clades besides clade A in this study may be due to other clades not being readily culturable under culture conditions used
here. The new isolates could be phylogenetically divided into four groups, though no sequences were identical to previously
reported Symbiodinium. Two of the four groups were closely related to symbiotic Symbiodinium clade A isolated from a variety of host species. One isolate group formed a highly supported monophyly with Symbiodinium types that have previously been characterized as “free-living”. The remaining isolate group, although within clade A, was
quite divergent from other clade A Symbiodinium. These results indicate that novel diversity of free-living Symbiodinium exists in coral sand. 相似文献
8.
Reports of bathymetric decrease in the total mycosporine-like amino acid (MAA) concentration of benthic invertebrates suggest that light gradients may be important determinants of MAA content. With the pronounced diel light changes, distinct temporal variations in MAA concentrations might also be expected. We examined the changes in the abundance of MAA in three shallow-water scleractinian corals, Pavona divaricata, Galaxea fascicularis and Montipora digitata from Okinawa, Japan, in relation to daily cycles in solar radiation and tested whether the species have different capabilities for protection against UVR depending on their MAA composition. The results show that symbiotic algae freshly isolated from the investigated coral species do not contain MAAs and that distribution of these compounds resided only within the animal tissue. Total MAA content in the tissue of P. divaricata, G. fascicularis and M. digitata rose rapidly at midday and significantly dropped at night. The observed variations were by a factor of two and, thus, very dramatic. For all the investigated coral species, total MAA concentrations were significantly correlated with the diurnal cycle in solar radiation, during both winter and summer seasons. Seawater temperature was significantly correlated with MAA levels only in the June experiment, but represented no more than 20% of the MAA variation in all three coral species, whereas solar radiation explained 60–70% of the MAA fluctuations. This suggests that MAAs are an integral component of the hard corals biochemical defense system against high solar irradiance stress. The diurnal increase in total MAA concentrations was due to an increase in the concentration of imino-MAA species of up to 2–2.5-fold of their pre-dawn values. In contrast, the oxocarbonyl-MAA mycosporine-glycine (Myc-Gly) showed the lowest (Tukey–Kramer HSD test: P<0.05) values at midday, compared to afternoon and night hours. Analysis of diel changes in chlorophyll fluorescence and chlorophyll a content of the investigated species revealed that P. divaricata and G. fascicularis were less sensitive to the high levels of ambient irradiance compared to M. digitata. In P. divaricata and G. fascicularis, Myc-Gly, an MAA with an antioxidant function, is the most abundant MAA, contributing about 70% to the total MAA pool, whereas the major MAA factions in M. digitata were represented by oxidatively robust imino-MAAs. We speculate that MAAs furnish scleractinian corals with protection from biologically damaging ultraviolet radiation through both the direct sunscreening activity of imino-MAAs and the antioxidant properties of oxocarbonyl-MAAs and suggest that the predominance, in the host tissue, of MAA species with an antioxidant ability may render corals more tolerant to high photosynthetically active and ultraviolet radiation.Communicated by T. Ikeda, Hakodate 相似文献
9.
Weddell seal samples taken from the Antarctic have been found to be contaminated with chlordane compounds. ΣChlordane () was present in blubber of seals at the range of 12 - 62 ng/g fresh weight. The order of chlordane compound concentrations was . Relative aboundance of -chlordane in Σchlordane is higher than that in humans. A probable explanation for their occurrence in the Antarctic is an airborne transport. 相似文献
10.
PCBs and chlorinated hydrocarbon pesticides such as DDTs and HCHs (BHCs) were measured in air, water, ice and snow samples collected around the Japanese research stations in Antarctica and adjacent oceans during December 1980 to March 1982. The atmospheric concentrations of chlorinated hydrocarbons decreased in the transport process from northern lands to Antarctica, but the compositions of PCBs, DDT compounds and HCH isomers were relatively uniform throughout this process. Regional and seasonal variations were found in aerial concentrations of these pollutants at Syowa Station and adjacent seas in Antarctica. Chlorinated hydrocarbons were also detected in snow, ice, lake water and sea water samples, in which rather high concentrations were found in snow and ice samples. This suggests that snow and ice serve as media of supply of these pollutants into Antarctic marine environment. Most interestingly, the concentrations of DDTs and higher chlorinated biphenyls were much lower in sea water under fast ice than in that from outer margin of pack ice. This indicates that the active removal of these pollutants is occurred in the sea under fast ice, and that is strongly associated with high primary productivity. It is, therefore, presumed that the concentrations of PCBs and DDTs in marine organisms living under fast ice in Antarctica could be lower than those in other oceans. 相似文献