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751.
This paper examines the relevance to groundwater management of Ostrom’s design principles for managing common property resources.
Experience in four case studies of groundwater management in the Murray Darling Basin in Australia and the Upper Guadiana
Basin in Spain suggests that while Ostrom’s design principles are relevant, sustainable groundwater management depends on
the effective collaboration between government authorities and water users. A flexible and adaptive management approach is
required, with collaboration between scientists, policy makers, water suppliers, and water users. Key management challenges
include agreeing on a sustainable level of extraction, and establishing effective coordination and collaboration, and monitoring
and control systems. Further case studies of groundwater management and their synthesis could make a useful contribution to
the transition towards sustainable groundwater management regimes. 相似文献
752.
Kerstin?BissingerEmail author Franz?X.?Bogner 《Environment, Development and Sustainability》2018,20(5):2079-2094
Environmental literacy is a key concept to promote individual behavioral changes toward a more sustainable lifestyle to consciously react to environmental challenges such as climate change. Promoting knowledge, attitudes and behaviors provides a reasonable basis to prepare adolescents for their future. A recently proposed environmental literacy model comprises three-dimensional knowledge, environmental attitudes and pro-environmental behavior. The present study applies this model by implementing an intervention focusing on tropical rainforests and climate change in a botanical garden, combining student-centered activities with self-dependent learning. Data from 283 10th graders quantify individual knowledge, attitudes and behavior scores. Knowledge acquisition, a positive development of the Inclusion of Nature in One's Self concept and increasing pro-environmental behavior intentions were found by comparing an intervention group with a test–retest group. In conclusion, our botanical garden’s intervention evidently furthered appreciative tendencies and even encouraged environmental literacy. 相似文献
753.
Muhammad?AzmiEmail authorView authors OrcID profile Akihiro?Tokai 《The Environmentalist》2016,36(4):335-350
Transportation sector is the second largest producer of greenhouse gas in Malaysia next to energy sector. It contributes to nearly 28 % of annual national carbon emissions due to its heavy dependency of hydrocarbons such as gasoline. If not properly managed, carbon dioxide emissions per capita are expected to nearly double in the next 5 years. Lack of interdisciplinary study on this sector has caused proper mitigation initiatives to be delayed, compounding the damage to the ecosystem. The objective of this study is to develop a dynamic probabilistic model to determine emissions and pollutants of transportation system in Malaysia using Analytica software, with focus on passenger cars for its large number over other vehicle classes. Several vehicle fleet management policies based on several key governmental, industrial and stakeholder’s intervention have been constructed and analyzed for a period of 25 years. This analysis found that greenhouse gas emissions and pollutants in 2040 can be reduced by up to 80 %, compared to emissions of 2020, without any adverse effect on vehicle demand nor the economy. However, without proper intervention, personal transportation system in Malaysia will generate nearly 80,000 kilotons of greenhouse gas annually by the year 2040. 相似文献
754.
Ploton P Pélissier R Proisy C Flavenot T Barbier N Rai SN Couteron P 《Ecological applications》2012,22(3):993-1003
Reducing Emissions from Deforestation and Forest Degradation (REDD) in efforts to combat climate change requires participating countries to periodically assess their forest resources on a national scale. Such a process is particularly challenging in the tropics because of technical difficulties related to large aboveground forest biomass stocks, restricted availability of affordable, appropriate remote-sensing images, and a lack of accurate forest inventory data. In this paper, we apply the Fourier-based FOTO method of canopy texture analysis to Google Earth's very-high-resolution images of the wet evergreen forests in the Western Ghats of India in order to (1) assess the predictive power of the method on aboveground biomass of tropical forests, (2) test the merits of free Google Earth images relative to their native commercial IKONOS counterparts and (3) highlight further research needs for affordable, accurate regional aboveground biomass estimations. We used the FOTO method to ordinate Fourier spectra of 1436 square canopy images (125 x 125 m) with respect to a canopy grain texture gradient (i.e., a combination of size distribution and spatial pattern of tree crowns), benchmarked against virtual canopy scenes simulated from a set of known forest structure parameters and a 3-D light interception model. We then used 15 1-ha ground plots to demonstrate that both texture gradients provided by Google Earth and IKONOS images strongly correlated with field-observed stand structure parameters such as the density of large trees, total basal area, and aboveground biomass estimated from a regional allometric model. Our results highlight the great potential of the FOTO method applied to Google Earth data for biomass retrieval because the texture-biomass relationship is only subject to 15% relative error, on average, and does not show obvious saturation trends at large biomass values. We also provide the first reliable map of tropical forest aboveground biomass predicted from free Google Earth images. 相似文献
755.
Unai?IriarteEmail author Jon?I?aki?álvarez-Uriarte Rubén?López-Fonseca Juan?Ramón?González-Velasco 《Environmental Chemistry Letters》2003,1(1):57-61
The relatively recent discovery of disinfection by-products has driven the main regulatory organisms to set maximum contaminant
levels for certain substances in drinking water. Trihalomethanes can be deemed as the most important group of by-products
in chlorinated surface waters. The present work has focused on trihalomethane formation in a full-scale water treatment plant.
We studied the effect of several factors, including ozonation, on trihalomethane levels in chlorinated treated water. The
treatment scheme also includes an ozonation step.
Electronic Publication 相似文献
756.
Brian?D.?WisendenEmail author Mike?S.?Pollock Robyn?J.?Tremaine Jeff?M.?Webb Monique?E.?Wismer Douglas?P.?Chivers 《Behavioral ecology and sociobiology》2003,54(5):485-490
Chemical and visual sources of information are used by aquatic prey during risk assessment. Here, we test the behavioral response of littoral prey fish to combinations of chemical alarm cues (skin extract) and the visual presence of a fish shoal. We scented minnow traps with either alarm cues or water (control) placed inside the trap, a jar that contained either a fish shoal or nothing (control), and recorded the number and species of fish captured. We predicted that chemical alarm cues would reduce the number of fish captured and that a fish shoal would increase the number of fish captured. The predicted effect of chemical and visual cues combined depended on the nature of the interaction. We found that the lowest catch rate was for the combination of alarm cue + no shoal, but the highest catch rate occurred for the combination of alarm cue + shoal. Fish shoal + water had the second highest catch rate and no shoal + water had the second lowest catch rate. We conclude that chemical alarm cues induce area avoidance in the absence of a shoal, but a strong behavioral proclivity to increase shoal cohesion in the presence of a shoal. The presence of a shoal in the traps induced alarmed fish to shoal with them and thus, enter the traps. This occurred even though traps were the source of the alarm cue.Communicated by A. Mathis 相似文献
757.
A psychrotrophic bacterial strain, Pseudoaltermonas sp. SM9913, was isolated from deep-sea sediment collected at 1,855 m depth. Two proteases produced by Pseudoaltermonas sp. SM9913 were purified, MPC-01 and MCP-02. MCP-01 is a serine protease with a molecular weight of 60.7 kDa. It is cold-adapted with an optimum temperature of 30–35°C. Its Km and Ea for the hydrolysis of casein were 0.18% and 39.1 kJ mol–1, respectively. It had low thermostability, and its activity was reduced by 73% after incubation at 40°C for 10 min. MCP-02 is a mesophilic metalloprotease with a molecular weight of 36 kDa. Its optimum temperature for the hydrolysis of casein was 50–55°C. The Km and Ea of MCP-02 for the hydrolysis of casein were 0.36% and 59.3 kJ mol–1, respectively. MCP-02 had high thermostability, and its activity was reduced by only 30.5% after incubation at 60°C for 10 min. At low temperatures, Pseudoaltermonas sp. SM9913 mainly produced the psychrophilic protease MCP-01.Communicated by O. Kinne, Oldendorf/Luhe 相似文献
758.
In species exhibiting egg guarding as well as communal egg laying, females may adopt the strategy of laying eggs in the nests of conspecifics and leaving without providing care (termed intraspecific brood parasitism). This study is the first to describe such a behavior in the insect Publilia concava (Hemiptera: Membracidae) through field studies that followed 849 marked females across 1,828 brood associations. While brood parasitism increased the total number of eggs in a host brood, it did not reduce the overall hatching success of host broods. Solitary females exhibited a range of guarding durations while parasitic females rarely remained to guard eggs. Females exhibiting the parasitic tactic increased their lifetime number of clutches without decreasing the number of solitary clutches that they were able to initiate. Estimates of egg number for these individual broods revealed that females adopting the parasitic tactic (in addition to solitary breeding) had higher lifetime fecundity relative to females that did not parasitize. In females that exhibited both tactics (solitary and parasitic), the parasitic tactic yielded a higher rate of oviposition. The major component of oviposition rate was the time to find hosts and this time decreased with increasing host availability across 222 replicate groups. Females exhibited a shift toward the parasitic tactic when host broods were more abundant (i.e. in larger groups and later in the season). However, the time to find hosts increased as the frequency of the parasitic tactic increased, suggesting that this tactic may be maintained through negative frequency dependence. The results of this study suggest that brood parasitism may be the preferred tactic, as part of a conditional strategy, when hosts are readily available with solitary breeding being the preferred tactic when hosts are in short supply. 相似文献
759.
Effects of kinship on territorial conflicts among groups of lions,<Emphasis Type="Italic"> Panthera leo</Emphasis> 总被引:2,自引:0,他引:2
Inclusive fitness theory predicts that cost of tolerant behaviour during competitive interactions is lower for relatives than for nonrelatives. Many studies have examined the effect of relatedness on behaviour within social groups. In contrast, kin selection acting among groups has received less attention. The genetic structure of African lion (Panthera leo) populations creates a strong possibility that kin selection among groups modifies behaviour during group conflicts. We used playback experiments and genetic data to investigate the importance of relatedness during simulated territorial disputes in lions. However, we found no effect of relatedness on territorial behaviour. Degree of relatedness did not affect the decision to approach simulated intrusions, nor did it affect the behaviour during approaches. The decision to approach was instead affected by position within the territory and consecutive playback number (a measure of habituation). For playbacks that did elicit an approach, the speed of response was not detectably affected by relatedness, but was affected by odds (the ratio of residents to intruders), number of intruders, number of bouts, presence of cubs, position within the territory, temperature and playback number. Although responses were unaffected by relatedness, it remains possible that other aspects of behaviour during natural encounters among prides are affected by kin selection.Communicated by L. Sterck 相似文献
760.
Sustainable use of the Amazon forest for timber production is conditioned by the effect of logging on the system's nutrient cycling. This paper reports the results of a soil moisture and soil water chemistry monitoring campaign before and immediately after a selective logging which removed 35 m3 wood/ha. Soil moisture was measured using tensiometers, and soil water chemistry using suction samplers in five disturbance classes: tractor tracks, clearing centres, clearing edges, forest edges and untouched forest. The results show that the soil under the tractor tracks and clearings contained more moisture than under the untouched forest. The suction samplers extracted substantially more nitrate, ammonium, calcium, magnesium and potassium from the clearing centres, the tractor tracks and the clearing edges than from the forest sites. The results are explained in terms of altered microbial activity, changes in crown interception and uptake by roots. 相似文献