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Brazilian adolescents’ food and beverages choices during school break: The Brazilian school meal program or food from other establishments?
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作者 Ana Carolina Leme Sonia Tucunduva Philippi Erika Christiane Toassa 《Open Journal of Preventive Medicine》 2012年第2期171-176,共6页
The purpose of this study was to identify the adolescents’ food preferences during school break. This was a qualitative cross-sectional study with 83 adolescents from a public school in the city of S?o Paulo. The par... The purpose of this study was to identify the adolescents’ food preferences during school break. This was a qualitative cross-sectional study with 83 adolescents from a public school in the city of S?o Paulo. The participants answered the following question: During the school break do you usually eat or drink something? Please justify your answer. The adolescents’ answers were analyzed through a Brazilian qualitative technique called Discourse of the Collective Subject. The ideas were: School Meal Program (36.2%), don’t eat anything (26.7%), bring from other establishments (20.1%) and drink water or juice (17.1%). The adolescents who chose the School Meal Program claimed they had no other options. On the other hand, the participants who refused the meal did so because they disliked it and as a result brought snacks from home or food markets. The Discourse of the Collective Subject helps the investigator to understand the ideas related to food and nutrition of a collectivity. 展开更多
关键词 Adolescents food Choices School Meal Program Competitive foods Qualitative Research
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Context-dependent responses of food-hoarding to competitors in Apodemus peninsulae:implications for coexistence among asymmetrical species 被引量:4
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作者 Hongyu NIU Jie ZHANG +3 位作者 Zhiyong WANG Guangchuan HUANG Chao PENG Hongmao ZHANG 《Integrative Zoology》 SCIE CSCD 2020年第2期115-126,共12页
Superior species may have distinct advantages over subordinates within asymmetrical interactions among sympatric animals.However,exactly how the subordinate species coexists with superior species is unknown.In the for... Superior species may have distinct advantages over subordinates within asymmetrical interactions among sympatric animals.However,exactly how the subordinate species coexists with superior species is unknown.In the forests west of Beijing City,intense asymmetrical interactions of food competition exist among granivorous rodents(e.g.Apodemus peninsulae,Niviventer confucianus,Sciurotamias davidianus and Tscherskia triton)that have broadly overlapping habitats and diets but have varied body size(range 15-300 g),hoarding habits(scatter vs larder)and/or daily rhythm(diurnal vs nocturnal).The smallest rodent,A.peninsulae,which typically faces high competitive pressure from larger rodents,is an ideal model to explore how subordinate species coexist with superior species.Under semi-natural enclosure conditions,we tested responses of seed-hoarding behavior in A.peninsulae to intraspecific and interspecific competitors in the situations of pre-competition(without competitor),competition(with competitor)and post-competition(competitor removed).The results showed that for A.peninsulae,the intensity of larder-hoarding increased and the intensity of scatter-hoarding declined in the presence of intraspecifics and S.davidianus,whereas A.peninsulae ceased foraging and hoarding in the presence of N.confucianus and T.triton.A.peninsulae reduced intensity of hoarding outside the nest and moved more seeds into the nest for larder-hoarding under competition from intraspecific individuals and S.davidianus.In most cases,the experimental animals could recover to their original state of pre-competition when competitors were removed.These results suggest that subordinate species contextually regulate their food-hoarding strategies according to different competitors,promoting species coexistence among sympatric animals that have asymmetrical food competition. 展开更多
关键词 asymmetrical food competition behavioral plasticity food-hoarding species coexistence sympatric rodents
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The impact of salps(Salpa thompsoni)on the Antarctic krill population(Euphausia superba):an individual-based modelling study
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作者 Bruno Walter Pietzsch Aaron Schmidt +3 位作者 Jürgen Groeneveld Dominik Bahlburg Bettina Meyer Uta Berger 《Ecological Processes》 SCIE EI CSCD 2023年第1期680-695,共16页
Background Krill(Euphausia superba)and salps(Salpa thompsoni)are key macrozooplankton grazers in the Southern Ocean ecosystem.However,due to differing habitat requirements,both species previously exhibited little spat... Background Krill(Euphausia superba)and salps(Salpa thompsoni)are key macrozooplankton grazers in the Southern Ocean ecosystem.However,due to differing habitat requirements,both species previously exhibited little spatial overlap.With ongoing climate change-induced seawater temperature increase and regional sea ice loss,salps can now extend their spatial distribution into historically krill-dominated areas and increase rapidly due to asexual reproduction when environmental conditions are favorable.Understanding the potential effects on krill is crucial,since krill is a species of exceptional trophic significance in the Southern Ocean food web.Negative impacts on krill could trigger cascading effects on its predators and prey.To address this question,we combined two individual-based models on salps and krill,which describe the whole life cycle of salp individuals and the dynamic energy budget of individual krill.The resulting new model PEKRIS(PErformance of KRIll vs.Salps)simulates a krill population for 100 years under varying chlorophyll-a concentrations in the presence or absence of salps.Results All of the investigated krill population properties(abundance,mean length,and yearly egg production)were significantly impacted by the presence of salps.On the other hand,salp density was not impacted if krill were present.The medians of krill population properties deviated during variable maximum chlorophyll-a density per year when salps were introduced by−99.9%(−234 individuals per 1000 m3)for krill density,−100%(−22,062 eggs per 1000 m3)for krill eggs and−0.9%(−0.3 mm)for mean length of krill.Conclusions If both species compete for the same food resource in a closed space,salps seem to inhibit krill populations.Further simulation studies should investigate whether this effect prevails if different phytoplankton sizes and consumption preferences of krill are implemented.Furthermore,direct predation of the two species or consumption of krill fecal pellets by salps could change the impact size of the food competition. 展开更多
关键词 Euphausia superba Salpa thompsoni Individual-based model food competition Population dynamics DEB theory
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