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11.
Current demand analysis methods do not formally cover the case of chronic deficits in quantity or quality of water and sanitation
services. These services include drinking water supply (DWS), wastewater and sewage treatment (WST), and municipal solid waste
management (MSW). Formal analysis of this case would, at minimum, define the deficit state and evaluate appropriate options
for reducing it. This paper proposes for a formal analytical model for municipal sanitation systems (MSS) that operate with
deficits in at least one of the constituent services of DWS, WST, or MSW. The model introduces definitions and notation for
describing the deficit state for conducting demand analysis on municipal sanitation systems. This model of demand analysis
for systems with chronic deficits will hereinafter be referred to as deficit analysis. A case study for Bacoor, Philippines is presented as an example. 相似文献
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Alejandra Valero Robyn Hudson Edgar Ávila Luna Constantino Macías Garcia 《Behavioral ecology and sociobiology》2005,59(2):262-269
When approached by males, females of the Amarillo fish (Girardinichthys multiradiatus) perform a behaviour called vibration or they are aggressively challenged. We quantified vibration and assessed whether it compromises the rate of feeding attempts in dyads kept in outdoor enclosures. Male approaches resulted in female vibration and in a reduced feeding rate. Vibration was not evoked by female–female aggression, which was frequent and always ended in the subordinate fleeing from the dominant female. Using a closed respirometer we found that vibration is costly; oxygen consumption of females was greater in the presence of a male (which evoked vibration) than in the presence of a non-familiar female (when no vibration occurred). By recording interactions of females confined in aquaria in the presence and in the absence of males, we confirmed that escaping is the only available response to deal with female aggression. Females kept without males participated in frequent aggressive (even lethal) interactions that did not abate while the subordinate female was in sight of the dominant, and which caused premature births and injuries. Yet in the alternative treatment aggression ceased when a male approached, prompting vibration in both females. Thus, in the Amarillo, in as much as it evokes energetically costly female vibrations, male courtship is an expression of sexual conflict. However, in the absence of males, frequent female aggression potentially annuls the benefits of not vibrating. We propose that a complete appraisal of the consequences of sexual conflict must include an assessment of the costs imposed by intra-sexual interactions. 相似文献
13.
Abhishek Sanskrityayn Vijay P. Singh Vinod Kumar Bharati Naveen Kumar 《Environmental Fluid Mechanics》2018,18(3):739-757
In the present study analytical solutions of a two-dimensional advection–dispersion equation (ADE) with spatially and temporally dependent longitudinal and lateral components of the dispersion coefficient and velocity are obtained using Green’s Function Method (GFM). These solutions describe solute transport in infinite horizontal groundwater flow, assimilating the spatio-temporal dependence of transport properties, dependence of dispersion coefficient on velocity, and the particulate heterogeneity of the aquifer. The solution is obtained in the general form of temporal dependence and the source term, from which solutions for instantaneous and continuous point sources are derived. The spatial dependence of groundwater velocity is considered non-homogeneous linear, whereas the dispersion coefficient is considered proportional to the square of spatial dependence of velocity. An asymptotically increasing temporal function is considered to illustrate the proposed solutions. The solutions are validated with the existing solutions derived from the proposed solutions in three special cases. The effect of spatially/temporally dependent heterogeneity on the solute transport is also demonstrated. To use the GFM, the ADE with spatio-temporally dependent coefficients is reduced to a dispersion equation with constant coefficients in terms of new position variables introduced through properly developed coordinate transformation equations. Also, a new time variable is introduced through a known transformation. 相似文献
14.
This paper investigates the extent and the nature of how the urban planning literature has addressed climate change adaptation. It presents a longitudinal study of 157 peer-reviewed articles published from 2000 to 2013 in the leading urban planning and design journals whose selection considered earlier empirical studies that ranked them these journals. The findings reveal that the years 2006–07 represent a turning point, after which climate change studies appear more prominently and consistently in the urban planning and design literature; however, the majority of these studies address climate change mitigation rather than adaptation. Most adaptation studies deal with governance, social learning, and vulnerability assessments, while paying little attention to physical planning and urban design interventions. This paper identifies four gaps that pertain to the lack of interdisciplinary linkages, the absence of knowledge transfer, the presence of scale conflict, and the dearth of participatory research methods. It then advocates for the advancement of participatory and collaborative action research to meet the multifaceted challenges of climate change. 相似文献
15.
Chauhan SV Chaurasia B Rana A 《Journal of environmental biology / Academy of Environmental Biology, India》2004,25(3):291-297
Cassia siamea plants growing at two different sites (polluted and non-polluted) on two important roads of Agra city exhibited significant differences in their flowering phenology and floral morphology. The flowering in plants growing at polluted site is delayed and there was a marked reduction in flowering density, flowering period, size of floral parts, pollen fertility, fruit and seed-set. SEM observations revealed the presence of well developed glandular structures and reduction in the number and size of large stomata on the anther surface at polluted site. These changes were found to be closely associated with the extent of air pollution caused mainly by significant in the number of automobiles. 相似文献
16.
Luna EM 《Disasters》2001,25(3):216-226
The Philippines is very vulnerable to natural disasters because of its natural setting, as well as its socio-economic, political and environmental context--especially its widespread poverty. The Philippines has a well-established institutional and legal framework for disaster management, including built-in mechanisms for participation of the people and NGOs in decision-making and programme implementation. The nature and extent of collaboration with government in disaster preparedness and mitigation issues varies greatly according to their roots, either in past confrontation and political struggles or traditional charity activities. The growing NGO involvement in disaster management has been influenced by this history. Some agencies work well with local government and there is an increasing trend for collaborative work in disaster mitigation and preparedness. Some NGOs, however, retain critical positions. These organisations tend to engage more in advocacy and legal support for communities facing increased risk because of development projects and environmental destruction. Entry points into disaster mitigation and preparedness vary as well. Development-oriented agencies are drawn into these issues when the community members with whom they work face disaster. Relief organisations, too, realise the need for community mobilisation, and are thus drawn towards development roles. 相似文献
17.
de Luna Mark Daniel G. Rabongue Anamie Garcia-Segura Sergi Lu Ming-Chun 《Environmental science and pollution research international》2021,28(30):40587-40597
Environmental Science and Pollution Research - Cartap is a thiocarbamate pesticide widely-used to protect rice crops, one of the most mass-produced cereals worldwide. Effluents... 相似文献
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da Silva Fabiano Santana Luna Carlos Bruno Barreto Siqueira Danilo Diniz da Silva Barbosa Ferreira Eduardo Araújo Edcleide Maria 《Journal of Polymers and the Environment》2022,30(3):1028-1044
Journal of Polymers and the Environment - This work aimed to investigate the biopolyethylene (BioPE)/wood powder (WP) composites compatibilized with polyethylene-grafted maleic anhydride (PE-g-MA),... 相似文献
20.
Lazar B Maslov L Romanić SH Gračan R Krauthacker B Holcer D Tvrtković N 《Chemosphere》2011,82(1):121-129
We analyzed 15 polychlorinated biphenyls (PCBs) and five organochlorine pesticides (OCPs) in fat tissue of 27 loggerhead sea turtles (Caretta caretta) from eastern Adriatic Sea with the curved carapace length ranging from 25.0 to 84.5 cm. The PCB profile was dominated by hexa- and hepta-chlorinated congeners, with PCB-153 (median: 114.9 ng g−1 wet mass), PCB-138 (80.0 ng g−1 w.m.), and PCB-180 (26.7 ng g−1 w.m.) detected with the highest levels. Toxic mono-ortho congeners PCB-118, PCB-105 and PCB-180 with dioxin-like toxicity were found in >70% samples. 4,4′-DDE (81.0 ng g−1 w.m.) prevailed the OCP signature, accounting for 80% of the total DDTs. A significant increasing trend in accumulation with size was found for PCB-52 (rs = 0.512, p < 0.01) and PCB-114 (rs = 0.421, p < 0.05). Comparison of our results with organochlorine contaminant (OC) pattern in some prey taxa suggest that contamination occurs primarily through the food web, with biomagnification factors of 0.14-6.99 which were positively correlated with the octanol-water partition coefficient (log Kow; p < 0.05). This study, based upon a fairly large sample size collected mostly from incidentally captured animals over a short time period (June 2001-November 2002), present a temporal snapshot of OC contamination in wild, free-ranging loggerheads from Adriatic feeding grounds and provide a baseline for monitoring the regional OC trends in this endangered species. 相似文献