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171.
In areas of war and armed conflict it is difficult to get trustworthy and coherent information. Civil society and human rights groups often face problems of dealing with fragmented witness reports, disinformation of war propaganda, and difficult direct access to these areas. Turkish Kurdistan was used as a case study of armed conflict to evaluate the potential use of satellite images for verification of witness reports collected by human rights groups. The Turkish army was reported to be burning forests, fields and villages as a strategy in the conflict against guerrilla uprising. This paper concludes that satellite images are useful to validate witness reports of forest fires. Even though the use of this technology for human rights groups will depend on some feasibility factors such as prices, access and expertise, the images proved to be key for analysis of spatial aspects of conflict and valuable for reconstructing a more trustworthy picture.  相似文献   
172.
Tillage and field scale controls on greenhouse gas emissions   总被引:3,自引:0,他引:3  
There is a lack of understanding of how associations among soil properties and management-induced changes control the variability of greenhouse gas (GHG) emissions from soil. We performed a laboratory investigation to quantify relationships between GHG emissions and soil indicators in an irrigated agricultural field under standard tillage (ST) and a field recently converted (2 yr) to no-tillage (NT). Soil cores (15-cm depth) were incubated at 25 degrees C at field moisture content and 75% water holding capacity. Principal component analysis (PCA) identified that most of the variation of the measured soil properties was related to differences in soil C and N and soil water conditions under ST, but soil texture and bulk density under NT. This trend became more apparent after irrigation. However, principal component regression (PCR) suggested that soil physical properties or total C and N were less important in controlling GHG emissions across tillage systems. The CO2 flux was more strongly determined by microbial biomass under ST and inorganic N content under NT than soil physical properties. Similarly, N2O and CH4 fluxes were predominantly controlled by NO3- content and labile C and N availability in both ST and NT soils at field moisture content, and NH4+ content after irrigation. Our study indicates that the field-scale variability of GHG emissions is controlled primarily by biochemical parameters rather than physical parameters. Differences in the availability and type of C and N sources for microbial activity as affected by tillage and irrigation develop different levels and combinations of field-scale controls on GHG emissions.  相似文献   
173.
Official Dutch food information apparently tries to avoid images but is implicitly shaped by the metaphor that food is fuel. The image of food as fuel and its accompanying view of the body as a machine are not maximally helpful for integrating two important human desires: health and pleasure. At the basis of the split between health and pleasure is the traditional mind–body dichotomy, in which the body is an important source of evil and bodily pleasure is sinful and dangerous. In the search for alternatives, new metaphors are proposed that integrate mind and body as well as pleasure and health. The relevance of metaphors for ethics is at least twofold. (1) Moral thought and theory are at least partly shaped by metaphors. In the light of this growing recognition, the analysis of morality needs innovation. (2) With regard to food, new metaphors, such as slow food, or the image of enjoyment as an art, enable a new search for morally responsible forms of hedonism, based on more love and respect for human as well as animal bodies. But new metaphors are specific and selective, just like old ones. I argue that a search for the best overall metaphor would be misguided, but that more diverse forms of attention to bodily aspects of life, including experiences related to food, will result in richer vocabularies of the body, the mind, and body–mind relations. This holds a promise of moral progress.  相似文献   
174.
An integrated system, consisting of Up-flow Anaerobic Sludge Blanket (UASB)-duckweed-tilapia ponds was used for recovery of sewage nutrients and water recycling. A UASB reactor with 40 liter working volume was used as pre-treatment unit followed by a series of three duckweed ponds for nitrogen recovery. The treated effluent and duckweed biomass was used to feed fishponds stocked with Nile tilapia (Oreochromis niloticus). The UASB reactor was fed with raw, domestic sewage at 6 h hydraulic retention time. The three duckweed ponds were stocked with Lemna gibba and fed with UASB effluent at 15 days hydraulic retention time. Nitrogen recovery from UASB effluent via duckweed biomass represented 81% of total nitrogen removal and 46.5% from the total nitrogen input to the system. In subsequent fishponds the nitrogen recovery from duckweed as fish feed was in the range of 13.4–20%. This nitrogen in fish biomass represented 10.6–11.5 g N from the total nitrogen in the raw sewage fed to the UASB reactor. The growth performance of tilapia (Oreochromis niloticus) showed specific growth rates (SGR) in the range of 0.53–0.97. The range of feed conversion ratio (FCR) and protein efficiency ratio (PER) were 1.2–2.2 and 2.1–2.28, respectively. The results of the experiments showed total fish yield and net fish yield in the range of 17–22.8 ton/ha/y and 11.8–15.7 ton/ha/y respectively. In conclusion UASB-duckweed-tilapia ponds provide marketable by-products in the form of duckweed and fish protein, which represent a cost recovery for sewage treatment.  相似文献   
175.
The effect of sampling protocol on ambient air hydrocarbon mixing ratios was examined on eight sampling days in Los Angeles during 2007 and 2008. Four protocols, which were based on previously published multi-city urban hydrocarbon studies in the United States, were compared and differences were quantified. Whole air canister samples were collected and analyzed for nonmethane hydrocarbons (NMHCs). Differing sampling protocols resulted in large differences in mixing ratios, up to an order of magnitude, for certain NMHCs on the same sampling day. However, the magnitude of the variability between NMHC levels obtained by the four protocols was not consistent throughout the eight sampling days. It was found that sampling time, followed by sampling location, had the greatest influence on the magnitude of the mixing ratio. Ratios between hydrocarbons, often used in urban studies to gain information on emission sources, also varied depending on the protocol used. Comparison of absolute NMHC mixing ratios collected in urban environments using differing sampling protocols should be made with care.  相似文献   
176.
177.
We assessed satellite derived tropospheric NO2 distribution on a global scale and identified the major NO2 hotspot regions. Combined GOME and SCIAMACHY measurements for the period 1996-2006 have been used to compute the trends over these regions. Our analysis shows that tropospheric NO2 column amounts have increased over the newly and rapidly developing regions like China (11 ± 2.6%/year), south Asia (1.76 ± 1.1%/year), Middle East (2.3 ± 1%/year) and South Africa (2.4 ± 2.2%/year). Tropospheric NO2 column amounts show some decrease over the eastern US (−2 ± 1.5%/year) and Europe (0.9 ± 2.1%/year). We found that although tropospheric NO2 column amounts decreased over the major developed regions in the past decade, the present tropospheric NO2 column amounts over these regions are still significantly higher than those observed over newly and rapidly developing regions (except China). Tropospheric NO2 column amounts show some decrease over South America and Central Africa, which are major biomass burning regions in the Southern Hemisphere.  相似文献   
178.
Increasing public concern for the welfare of fish species that human beings use and exploit has highlighted the need for better understanding of the cognitive status of fish and of their ability to experience negative emotions such as pain and fear. Moreover, studying emotion and cognition in fish species broadens our scientific understanding of how emotion and cognition are represented in the central nervous system and what kind of role they play in the organization of behavior. For instance, on a macro neuro-architecture level the brains of fish species look dramatically different from those of mammals, while such a dramatic difference does not (always) occur at the level of emotion- and cognition-related behavior. Here, therefore, we discuss the evidence of emotion and cognition in fish species related to underlying neuro-architecture and the role that emotion and cognition play in the organization of behavior. To do so we use a framework encompassing a number of steps allowing a systematic approach to these issues. Emotion and cognition confer on human and non-human animals the capacity to compliment and/or override immediate reflexes to stimuli and so allow a large degree of flexibility in behavior. Systematic research on behavior that in mammals is indicative of emotion and cognition has been conducted in only a few fish species. The data thus far indicate that in these species brain-behavior relationships are not fundamentally different from those observed in mammals. Furthermore, data from other studies show evidence that behavior patterns related to emotion and cognition vary between fish species as well within fish species, related to sex and life history stage for example. From a welfare perspective, knowledge of such variability will potentially help us to design optimal living conditions for fish species kept by humans.  相似文献   
179.
The effects of limestone dust deposition on vegetation in desert ecosystems have not yet been reported. We investigated these effects in a succulent shrub from the Namib Desert at a limestone quarry near Skorpion Zinc mine (Namibia). Effects of limestone dust were determined in Zygophyllum prismatocarpum (dollar bush) plants with heavy, moderate and no visible foliar dust cover by means of chlorophyll a fluorescence measurements. Limestone dust deposition decreased overall plant performance through loss of chlorophyll content, inhibition of CO(2) assimilation, uncoupling of the oxygen-evolving complex and decreased electron transport. Importantly, dynamic recovery occurred after termination of limestone extraction at the quarry. Recovery was accelerated by rainfall, mainly because of dust removal from leaves and stimulation of new growth. These results indicate that limestone dust has severe effects on photosynthesis in desert shrubs, but that recovery is possible and that, in arid environments, this process is modulated by rainfall.  相似文献   
180.
Rates and direction of movement in the sand dollar Peronella lesueuri were measured in summer and winter in Cockburn Sound, a large coastal embayment in south-western Australia. P. lesueuri was found to have a diurnal activity pattern throughout the year and had a greater movement rate in the summer (mean of 5.3 cm h?1, day; 3.9 cm h?1, night) than in the winter (mean of 2.7 cm h?1, day; 2.0 cm h?1, night). Seasonal change in temperature and physiological requirements by the sand dollar are the most likely reason for the seasonal differences. Reasons for diurnal variation were not clear. Direction of movement was found to be random at both times of the year. Based on these movement rates, one sand dollar can bioturbate an approximate area of 0.1 m2 day?1 and 36.4 m2 year?1. At a conservative density estimate of 0.5 sand dollars per m2 it takes approximately 20 days for the sand dollars to rework the entire area of the sediments in the habitats they occupy.  相似文献   
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