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951.
Environmental Science and Pollution Research - Indoor air pollution is an important risk factor for the generation of lung diseases in developing countries. The indigenous population is...  相似文献   
952.
Although there has been a worldwide growing concern regarding solid-waste management, the rural area has been left behind on this matter. It is common knowledge that the lack of waste management is very detrimental to the environment and impact seriously the public health. Therefore, the aim of this work is to contribute to the decision-making process regarding waste management in the rural area by proposing a new methodology using the combination of risk analysis and complementary sustainability criteria. The proposed methodology was demonstrated through a case study in the State of Mato Grosso do Sul, Brazil. A field survey was performed to define the current scenarios and three new scenarios were proposed. The risk analysis showed that the major risk to which residents are vulnerable to is the appearance of vectors that can cause various types of diseases. Besides that, only 30% of rural Quilombola communities of Mato Grosso do Sul have waste collection and the predominant scenario is the burning of dry waste and use of organic waste for animal feeding. Using the complementary relevant criteria, the most suitable scenario do the studied communities would be the combination of household composting and source separation of dry waste. The proposed methodology can be easily applied to other rural regions seeking for sustainable waste management systems.  相似文献   
953.
Humble leadership is attracting increased scholarly attention, but little is known about its effects when used in conjunction with less humble leadership behaviors that rely on a perception of the leader as confident and charismatic. This study contrasts the effects on top management team (TMT) potency and organizational performance of a more humble (feedback seeking) and a less humble (vision) CEO leader behavior. We hypothesize that CEO feedback seeking increases TMT potency and firm performance by communicating to TMT members that the organization values their input and encouraging their own feedback seeking, whereas CEO vision articulation influences these outcomes by fostering greater clarity about the firm's direction, and an enhanced ability to coordinate efforts within the TMT. CEOs who have not developed a vision can achieve a similar positive impact on TMT potency and firm performance by seeking feedback. In a sample of CEOs and TMT members from 65 firms, both CEO feedback seeking and vision articulation exhibit positive direct relationships with firm performance. However, only feedback seeking displays an indirect effect on performance via TMT potency. Finally, CEO feedback seeking has its strongest effects on firm performance and TMT potency for CEOs who are not seen as having a vision.  相似文献   
954.
Mining plays an important role in Brazilian exports. On the other hand, large urban centers like São Paulo, with approximately 21 million inhabitants, also demand an increasing domestic consumption of natural resources, such as construction aggregate. There are many quarries located in the surroundings of urban centers in Brazil, competing with the growth of urbanized areas. Such proximity leads to a series of conflicts involving quarries and surrounding communities, where the increase in noise levels is highlighted. Operations in quarries, in general, are intermittent. Noisier equipment, such as drilling rigs and primary crushers, operates only a few hours during the day, while other operations, such as screening and secondary and tertiary crushing, are more constant. This paper presents a study carried out in a quarry located near São Paulo, where in addition to conventional short term noise measurements at surrounding receptors, one noise monitoring station was installed, allowing to identify the noisiest moments during the quarry operating time. Through data transmitted by wireless technology, it was possible to follow the noise variations emitted from mining activities in real time and observe the noisiest events that were recorded for events that exceeded the established standards. A mobile application associated to this monitoring station facilitated the quarry’s manager and employees to access immediately the monitoring information. Therefore, by using this system, it was possible to evaluate the effectiveness of noise reduction measures already taken and indicate what steps still need to be held.  相似文献   
955.
956.
The mullet fishery system encompasses a complex arrange of ecological and socioeconomic factors interacting in multiple scales on the Southern-Southeastern Brazilian coast. Similarly, to other fisheries in developing countries, overfishing and poor governance have been threatening the resilience of the mullet fishery. In this paper, we explore aspects related to fisheries management from the perspective of the concept of resilience. The industrial and artisanal fishery sectors represent the different stakeholders. The main issues of concern are related to failures in the fisheries management to properly address equity in resource access and resource use sustainability among stakeholders. Asymmetry in technology and political and economic power affect food security and income generation especially for subsistence and small-scale fishing. Despite changes in rules-in-use, overfishing and conflicts between resource users are still relevant. Fishery dynamics and resource availability are greatly affected locally by forces such as pollution, urbanization, non-selective fishing, and regionally, by the El Niño Southern Oscillation (ENSO), and industrial (purse-seine) fishery. Considering the influence of ENSO on this fishery, a time span of at least 7 years to investigate this system could provide better answers to improve the management. Effective resilient fisheries should rely on three aspects. First, there should be a flexible fish allocation system based on ecosystem variability. Secondly, fish allocation should prioritize food security and poverty alleviation. Thirdly, a monitoring system should be implemented that takes into consideration ecosystem, fisheries and human dimensions to support a flexible and adaptive fisheries management, with resilient fisheries as an ultimate goal.  相似文献   
957.
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   
958.
Currently, artisanal fisheries in fresh water reservoirs have been losing ground to commercial fish farming and a great deal of fishery resources are being threatened by human interventions, such as reservoir management and increasing net-cage aquaculture. This study aims to understand the impacts of environmental changes on fishery resources and analyse the migratory fish breeding season as a missing link for fishery management in the semi-arid area of the São Francisco River Basin. Among the 870 fishermen operating in the Pernambuco part of the Itaparica Reservoir, 10% were interviewed and affirmed that fish stocks have been compromised due to the closed fishing period’s incoherence, exotic species insertion, and changes to the river flow caused by reservoir construction and operation. A significant correlation was observed between the Reproductive Activity Index (RAI) and precipitation (p?=?0.745) as well as between the RAI and the river’s flow (p?=??0.909). This shows how important it is to consider both the semi-arid climate setting and reservoir operation in determining the closed period which should safeguard fish reproduction. Monitoring the fish reproduction period and research on the reproductive biology of native fish species is needed in the São Francisco River Basin’s different stretches in order to guarantee valuable fish stocks and fisheries maintenance. Integrated action between the fish resource users, civil society, and federal bodies/agencies is essential in order to mitigate impacts and improve fish production systems, not only in Brazil, but in other regions experiencing a similar scenario.  相似文献   
959.
Sludge generated in intensively managed tilapia fingerling breeding ponds near the Itaparica Dam in the semi-arid Brazilian northeastern region was tested as a soil conditioner to produce lettuce in an effort to mitigate the present environmental impact of the deposition of this sludge, thereby giving it a productive destiny. A greenhouse experiment was performed by mixing the sludge with a Haplic Planosol topsoil, a characteristic soil of the region, so that the sludge corresponded to 0, 25, 50, 75, and 100% of the mixture (substrate). The experiment was set up as a randomized block design with five blocks, each with three pots (5-kg substrate per pot) of the five sludge proportion treatments. One lettuce plant was transplanted into each pot, maintained under greenhouse conditions, and harvested 35 days after transplanting. Sludge, soil, and the substrates were evaluated for nutrient concentration and physical characteristics. Green and dry weights, stem diameter, and nitrogen, phosphorus, and potassium concentrations in the aboveground parts of the lettuce plants were determined. Sludge incorporation into the substrate improved its chemical and physical characteristics. The lettuce plants grew best in the substrate with 75% sludge, increasing its biomass production by 50% and more than doubling its nitrogen uptake.  相似文献   
960.
The hydrothermal carbonization of sewage sludge has been studied as an alternative technique for the conversion of sewage sludge into value-added products, such as soil amendments. We tested the toxicity of biosolid hydrochar (Sewchar) to earthworms. Additionally, the toxicity of Sewchar process water filtrate with and without pH adjustment was assessed, using brine shrimps as a model organism. For a Sewchar application of 40 Mg ha?1, the earthworms significantly preferred the side of the vessel with the reference soil (control) over side of the vessel with the Sewchar treatments. There was no acute toxicity of Sewchar to earthworms within the studied concentration range (up to 80 Mg ha?1). Regarding the Sewchar process water filtrate, the median lethal concentration (LC50) to the shrimps was 8.1% for the treatments in which the pH was not adjusted and 54.8% for the treatments in which the pH was adjusted to 8.5. The lethality to the shrimps significantly increased as the amount of Sewchar process water filtrate increased. In the future, specific toxic substances in Sewchar and its process water filtrate, as well as their interactions with soil properties and their impacts on organisms, should be elucidated. Additionally, it should be identified whether the amount of the toxic compounds satisfies the corresponding legal requirements for the safe application of Sewchar and its process water filtrate.  相似文献   
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