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471.
472.
The Geographic Profiling (GP) is a data analysis tool that has great potential. Presently, it is used only minimally, and is almost always used “as it is”, independently on other analysis or data processing methods. GP was initially created as a forensic tool, to find the origin of a series of events (crimes) done by a single actor. However, using this method in integration with others, it is possible to enlarge the opportunities of geographical data analysis. The promising results of this method in integration with others, even if some of them are quite well known methods since many years–and thus well tested–show a number of further possible applications. Here we treat data clustering and partitioning with Kmeans and Dbscan methods; space partitioning (Voronoi tessellation) and a method to assign weights to the events constituting the data set. The software used in this review was written in Python, was released under GPL license and is available on Bitbucket (https://bitbucket.org/ugosnt/al_and_ugo/). 相似文献
473.
D. Pellegrino U. Schirpke D. Marino 《Journal of Environmental Planning and Management》2017,60(3):383-398
In Europe, biodiversity conservation relies on the Natura 2000 network. However, it is often difficult to ensure the favourable conservation status of species and habitats due to scarce financial resources. Therefore, we examined the current management strategies and conditions of three Italian Natura 2000 sites based on a questionnaire and stakeholder meetings. Additionally, we qualitatively assessed the potential of ecosystem services provision. Then an A'WOT analysis was carried out to identify and highlight internal and external factors affecting natural and semi-natural ecosystems and the socio-economic context, aiming to propose new instruments and approaches for effective management. The analysis revealed opportunities for developing tourism and the high potential of regulating services, whereas the bureaucratic burden and a lack of funding threaten the attainment of biodiversity conservation goals. Thus, we propose that payments for ecosystem services should be considered to support the effective management of Natura 2000 sites. 相似文献
474.
Ajieh Mike U. Isagba Ebuwa S. Ihoeghian Newton Edosa Valerie I. O. Amenaghawon Andrew Oshoma Cyprian E. Erhunmwunse Nosakhare Obuekwe Ifeyinwa S. Tongo Isioma Emokaro Christopher Ezemonye Lawrence I. N. 《Environment, Development and Sustainability》2021,23(9):13182-13199
Environment, Development and Sustainability - The use of wastes for biogas production has been restricted to few feedstock like cattle manure and food waste. Increasing the feedstock base for... 相似文献
475.
Sediment cores from four boreal and remote lakes in a south to north transect in central Sweden were analysed for acid leachable silver, antimony, thallium and indium in the solid sediment phase and the corresponding porewater. Dating of the cores was made by their content of acid leachable lead and the (206)Pb/(207)Pb ratio, in one lake also by (210)Pb. The impact of diagenesis on element redistribution in the sediments was included and found to be minor except for thallium. The results show lowered concentrations towards the north and most intense accumulation after the Second World War, which is taken as evidence for atmospheric deposition being the primary source. Indium has declining concentrations in recent strata while silver and antimony increase. Thallium has lowered acid-leachable concentrations in recent strata. For all metals the impact of domestic industrialisation as well as the early industrialisation of central Europe is discernible. Only thallium appears to reach a geological background at depths that correspond to the late 18th century. For the other metals elevated levels are concluded. 相似文献
476.
The optimized BCR sequential extraction procedure was applied to nine roadside soil samples for the determination of Cd, Cr,
Pb and Ni. The extractable metals were isolated into three operationally defined fractions viz: acid extractable, reducible
and oxidizable. The residue was treated with aqua regia solution. Metal analysis was done using flame atomic absorption spectrophotometry
with air–acetylene flame. Results obtained showed the concentrations of the metals as relative abundance in the mobile phases
of the samples (based on the sum of the first three fractions) are in the following order: Cd(91.9) > Pb(82.8) > Ni(49.5) > Cr(39.0).
The most non-mobilizable metals were Cr and Ni which are generally lithogenic, associated with the silicate matrix, and the
order is as follows: Cr(61.0) > Ni(50.5) > Pb(17.2) > Cd(8.1). The recovery of all the metals expressed as the ratio of total
metal concentration to fractional sum of the optimized BCR sequential extraction procedure was of the order: Cr(95.6) > Pb(95.0) > Ni(94.8) > Cd(92.4). 相似文献
477.
U.S. Korsholm A. Baklanov A. Gross J.H. Sørensen 《Atmospheric environment (Oxford, England : 1994)》2009,43(31):4805-4810
Traditionally, transport and dispersion models are offline coupled to meteorological drivers, receiving pre-processed output at regular coupling intervals. However, today meteorological models have reached urban and cloud resolving scales and online models integrating meteorological and dispersion models have been developed. In this study the online coupled model, Enviro-HIRLAM, which can also run in offline mode, was used to compare online and offline representations of meso-scale disturbances. The online model was evaluated using data from the first European Tracer Experiment (ETEX-1) and produced satisfactory results. Meso-scale influences during the simulation pertube the plume during long-range transport, leading to a double peak structure at a specific measurement station. The meso-scale influence was investigated by varying the offline coupling interval which was shown to be important in constraining the influence of meso-scale disturbances on plume structure in coarse resolution. 相似文献
478.
B. Reidy J. Webb T.H. Misselbrook H. Menzi H.H. Luesink N.J. Hutchings B. Eurich-Menden H. Döhler U. Dämmgen 《Atmospheric environment (Oxford, England : 1994)》2009,43(9):1632-1640
Six N-flow models, used to calculate national ammonia (NH3) emissions from agriculture in different European countries, were compared using standard data sets. Scenarios for litter-based systems were run separately for beef cattle and for broilers, with three different levels of model standardisation: (a) standardized inputs to all models (FF scenario); (b) standard N excretion, but national values for emission factors (EFs) (FN scenario); (c) national values for N excretion and EFs (NN scenario). Results of the FF scenario for beef cattle produced very similar estimates of total losses of total ammoniacal-N (TAN) (±6% of the mean total), but large differences in NH3 emissions (±24% of the mean). These differences arose from the different approaches to TAN immobilization in litter, other N losses and mineralization in the models. As a result of those differences estimates of TAN available at spreading differed by a factor of almost 3. Results of the FF scenario for broilers produced a range of estimates of total changes in TAN (±9% of the mean total), and larger differences in the estimate of NH3 emissions (±17% of the mean). The different approaches among the models to TAN immobilization, other N losses and mineralization, produced estimates of TAN available at spreading which differed by a factor of almost 1.7. The differences in estimates of NH3 emissions decreased as estimates of immobilization and other N losses increased. Since immobilization and denitrification depend also on the C:N ratio in manure, there would be advantages to include C flows in mass-flow models. This would also provide an integrated model for the estimation of emissions of methane, non-methane VOCs and carbon dioxide. Estimation of these would also enable an estimate of mass loss, calculation of the N and TAN concentrations in litter-based manures and further validation of model outputs. 相似文献
479.
Spermatophore characteristics in bushcrickets vary with parasitism and remating interval 总被引:4,自引:0,他引:4
Male bushcrickets provide females with a nuptial gift, a spermatophore, which is transferred to females at mating. The spermatophore
consists of a gelatinous mass, the spermatophylax, and the sperm-containing ampulla. Male spermatophore size is positively
correlated with insemination rate and female refractory period and therefore with male reproductive success. In this study,
we examined spermatophylax weight, ampulla weight and sperm number in males of Poecilimon mariannae parasitized by the acoustically orienting fly Therobia leonidei. We show that in parasitized males, spermatophylax weight decreases with the level of parasitism. In line with the hypothesis
that parasitism is a cost to reproduction, we found that spermatophylax weight was reduced at remating. In contrast, the replenishment
of the spermatophylax in unparasitized males was complete after 2 days and was increased no further after 3 days. Both sperm
number and ampulla weight showed an increase over time since last mating and sperm production was estimated at a constant
rate of 500,000 per day in all individuals, regardless of parasitism. The allocation of investment in components of the spermatophore
varies greatly with parasitism and remating. Both factors had rather independent effects on spermatophore constitution, revealing
functional constraints acting on spermatophore characteristics in bushcrickets, which are important for understanding the
selection pressures working on its components.
Received: 13 September 1999 / Received in revised form: 4 February 2000 / Accepted: 13 March 2000 相似文献
480.
T. Wagner L. M. Arango Isaza S. Grundmann U. Dörfler R. Schroll M. Schloter A. Hartmann H. Sandermann D. Ernst 《Water, Air, & Soil Pollution: Focus》2008,8(2):155-162
The gene transfer from glyphosate tolerant soybean to Bradyrhizobium japonicum was evaluated in a free-air lysimeter experiment under natural conditions and increasing selection pressure, to monitor for the probability of horizontal gene transfer (HGT). A large volume lysimeter study that offers conditions comparable to normal farming was conducted in 2004 and 2005 with Roundup Ready® (RR) soybean and Roundup® application according to agricultural practice. Analysis of nodules showed, as expected, the presence of the transgenic 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS). However, in bacteroids that were isolated from nodules and then cultivated for several rounds in the presence of high levels of glyphosate, the EPSPS gene could no longer be detected. This indicates no stable HGT transfer of the whole EPSPS gene under field conditions. 相似文献