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101.
102.
Ken USHIJIMA Mitsuteru IRIE Neni SINTAWARDANI Jovita TRIASTUTI Umi HAMIDAH Tadaharu ISHIKAWA Naoyuki FUNAMIZU 《Frontiers of Environmental Science & Engineering》2013,7(1):120-126
Material flow analysis (MFA) and value flow analysis (VFA) were applied to the sanitation system in an urban slum in Indonesia. Based on the results of the MFA and VFA, garbage and excreta disposal costs were evaluated to be 0.7% and 1.1%, respectively, of per capita income. Such value flows seem reasonable in light of the recognized affordability to pay (ATP) standard. However, current excreta disposal methods create negative impacts on downstream populations. Because such disadvantages do not go back to disposers, but passed to downstream, the current value flow structure does not motivate individual toilet users to install treatment facility. Based on current material and value flow structures, a resource recycling sanitation system scenario was examined. Based on VFA, an affordable initial cost for such a system was calculated; this was found to be comparable in price to a cheaper composting toilet that is currently available in the market. 相似文献
103.
Integrated biogeochemical modelling of nitrogen load from anthropogenic and natural sources in Japan
Bin He Taikan Oki Shinjiro Kanae Goro Mouri Ken Kodama Daisuke Komori Shinta Seto 《Ecological modelling》2009
This study proposed an integrated biogeochemical modelling of nitrogen loads from anthropogenic and natural sources in Japan. Firstly, the nitrogen load (NL) from different sources such as crop, livestock, industrial plant, urban and rural resident was calculated by using datasets of fertilizer utilization, population distribution, land use map, and social census. Then, the nitrate leaching from soil layers in farmland, grassland and natural conditions was calculated by using a terrestrial nitrogen cycle model (TNCM). The Total Runoff Integrating Pathways (TRIP) was used to transport nitrogen from natural and anthropogenic sources through river channels, as well as collect and route nitrogen to the river mouths. The forcing meteorological and hydrological data is a 30-year (1976–2005) dataset for Japan which were obtained by the land surface model, Minimal Advanced Treatments of Surface Interaction and Runoff (MATSIRO). For the model validation, we collected total nitrogen (TN) concentration data from 59 rivers in Japan. As a comparison result, calculated TN concentration values were in good agreement with the observed ones, which shows the reliability of the proposed model. Finally, the TN loads from point and nonpoint sources were summarized and evaluated for 59 river basins in Japan. The proposed modelling framework can be used as a tool for quantitative evaluation of nitrogen load in terrestrial ecosystems at a national scale. The connection to land use and climate data provides a possibility to use this model for analysis of climate change and land use change impacts on hydrology and water quality. 相似文献
104.
We introduce a new index for measuring perpendicularity of animal movements with respect to a boundary (e.g., a habitat patch edge), and provide a computer algorithm for its calculation. Our index, η, improves on an approach that measures perpendicularity with respect to a fixed boundary direction. This is because η accounts for moment-to-moment trajectories relative to nearest-neighbor boundary attributes at the scale of an animal's movement. Our algorithm prp calculates η efficiently and accurately with both synthetic data and large telemetry datasets. In addition, we have included routines in prp which account for scenarios inherently problematic to perpendicularity estimators. 相似文献
105.
Herman Wong Eric Wolvovsky Ken Richmond James Paumier 《Journal of the Air & Waste Management Association (1995)》2016,66(11):1121-1140
AERCOARE is a meteorological data preprocessor for the American Meteorological Society and U.S Environmental Protection Agency (EPA) Regulatory Model (AERMOD). AERCOARE includes algorithms developed during the Coupled-Ocean Atmosphere Response Experiment (COARE) to predict surface energy fluxes and stability from routine overwater measurements. The COARE algorithm is described and the implementation in AERCOARE is presented. Model performance for the combined AERCOARE-AERMOD modeling approach was evaluated against tracer measurements from four overwater field studies. Relatively better model performance was found when lateral turbulence measurements were available and when several key input variables to AERMOD were constrained. Namely, requiring the mixed layer height to be greater than 25 m and not allowing the Monin Obukhov length to be less than 5 m improved model performance in low wind speed stable conditions. Several options for low wind speed dispersion in AERMOD also affected the model performance results. Model performance for the combined AERCOARE-AERMOD modeling approach was found to be comparable to the current EPA regulatory Offshore Coastal Model (OCD) for the same tracer studies. AERCOARE-AERMOD predictions were also compared to simulations using the California Puff-Advection Model (CALPUFF) that also includes the COARE algorithm. Many model performance measures were found to be similar, but CALPUFF had significantly less scatter and better performance for one of the four field studies. For many offshore regulatory applications, the combined AERCOARE-AERMOD modeling approach was found to be a viable alternative to OCD the currently recommended model.
Implications: A new meteorological preprocessor called AERCOARE was developed for offshore source dispersion modeling using the U.S. Environmental Protection Agency (EPA) regulatory model AERMOD. The combined AERCOARE-AERMOD modeling approach allows stakeholders to use the same dispersion model for both offshore and onshore applications. This approach could replace current regulatory practices involving two completely different modeling systems. As improvements and features are added to the dispersion model component, AERMOD, such techniques can now also be applied to offshore air quality permitting. 相似文献
106.
This study investigated bioamplification of polychlorinated biphenyls (PCBs) in yellow perch (Perca flavescens) eggs resulting from nutrient utilization by developing embryos during incubation. Newly fertilized eggs containing trace levels of PCBs via maternal deposition were collected from an aquaculture pond in which adult broodstock had been reared over their natural lives. The eggs were incubated using a flow through system that received the same pond water at in-situ temperatures from which they were spawned. Replicate samples of eggs were collected at six time points throughout incubation, ranging from day 0 (newly fertilized eggs) to post-hatch larvae (2-d old). Congener specific PCB fugacities in pooled egg samples showed increases over the incubation period. Just prior to hatching, incubated eggs averaged 2.7-fold higher PCB fugacities compared to fresh eggs. The increase in PCB fugacity with egg incubation time was independent of chemical KOW. After hatching, PCB residues were lost from the larvae, attenuating the maximum chemical fugacity achieved in late-incubated eggs. However, the rate of PCB elimination in the early larvae stages was KOW dependent such that a significant larvae/egg fugacity ratio was still evident for intermediate and highly hydrophobic compounds 2 d post-hatching. This study provides the first evidence of in-ovo PCB bioamplification in eggs of an aquatic species and suggests that incubating fish embryos are exposed to higher chemical fugacities in-ovo than would be predicted by maternal deposition alone. 相似文献
107.
Do female black-capped chickadees prefer high-ranking males as extra-pair partners? 总被引:14,自引:0,他引:14
Ken Otter Laurene Ratcliffe Denise Michaud Peter T. Boag 《Behavioral ecology and sociobiology》1998,43(1):25-36
Previous studies have shown that some female black-capped chickadees (Poecile atricapillus) solicit copulations from males that rank higher in winter flocks than their social mates, and extra-pair paternity in nests
occurs commonly enough to be considered a potential female mating tactic. This study uses blood samples collected in 1992–1995
from 58 families of black-capped chickadees to test whether females with extra-pair offspring have chosen extra-pair sires
higher in social rank than their mates. Paternity was assessed with multilocus DNA fingerprinting in 1992–1994 nests and with
microsatellite and single-locus minisatellite DNA typing in 1995 nests. Seventeen of 58 nests (29.3%) contained young genetically
mismatched with their social father. In 11 of 15 cases where the identity of the extra-pair male was known, the extra-pair
male was dominant to the social father. Using data from 29 nests located in 1994 and 1995 for which we had the most data on
relative ranks of males, high-ranking males had greater realized reproductive success than low-ranking males as a result of
extra-pair fertilizations. There was no significant difference between the number of nests containing extra-pair young of
females mated to low-ranked versus high-ranked males. Two nests in 1995 contained young either genetically mismatched with
both social parents (intraspecific brood parasitism) or, in one nest, genetically mismatched with the social mother but not
the social father (quasi-parasitism). The implications of female strategies acquiring genetic benefits through extra-pair
copulations are discussed.
Received: 7 July 1997 / Accepted after revision: 14 March 1998 相似文献
108.
109.
Masako Nakamura Ken Okaji Yoshimi Higa Eiji Yamakawa Satoshi Mitarai 《Marine Biology》2014,161(11):2521-2530
Boom and bust dynamics are a prominent characteristic of the crown-of-thorns starfish (Acanthaster planci) populations. Outbreaking starfish populations damage coral communities extensively and then often disappear quickly. In contrast, Onna village, on the central west coast of Okinawa Island, Japan, has been experiencing chronically high population densities of A. planci for decades. In this study, we examined spatial and temporal population dynamics of A. planci along the coast of Onna village, using removal data gathered over 24 years by a local fisheries cooperative. The results demonstrate that A. planci populations along the Onna coast often experienced high densities prior to 2003 and that recently, populations have again been increasing drastically. Size-frequency distributions suggest multiple, successive recruitment, as one of the driving factors maintaining A. planci populations in this location. Moreover, within the Onna area, the timing of outbreak peaks varied among different locations, showing a northward progression. 相似文献
110.