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311.
Chemicals such as those used for scent marking, or visual cues such as color badges, can transmit information pertaining to
different aspects of individual, group and species recognition and attributes. Here, we show that complex acoustic cues, such
as calls also have the capacity for such information transfer. Although songs are usually attributed to birds, rock hyraxes
(Procavia capensis) engage in a rich and complex vocalizing behavior that we term ‘singing’. Previous studies on various species have shown
that a specific vocalization can closely reflect a specific attribute. Using a series of multiple regressions, we show that
a single complex vocalization by the adult male rock hyrax closely reflects numerous individual traits, possibly encoding
various types of biologically important information (multiple-messages hypothesis). Our study reveals that hyrax songs provide
accurate information regarding body weight, size and condition, social status and hormonal state of the singer. We also show
that these independent data are sent in a sequential manner, a pattern that probably allows a better partition of the messages
embedded in the song. Our results imply that animals, through complex individual vocalizations, can potentially advertise
multiple individual attributes in the same manner as that produced by chemical scent marking.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
312.
The study described in this paper developed a model of animal movement, which explicitly recognised each individual as the central unit of measure. The model was developed by learning from a real dataset that measured and calculated, for individual cows in a herd, their linear and angular positions and directional and angular speeds. Two learning algorithms were implemented: a Hidden Markov model (HMM) and a long-term prediction algorithm. It is shown that a HMM can be used to describe the animal's movement and state transition behaviour within several “stay” areas where cows remained for long periods. Model parameters were estimated for hidden behaviour states such as relocating, foraging and bedding. For cows’ movement between the “stay” areas a long-term prediction algorithm was implemented. By combining these two algorithms it was possible to develop a successful model, which achieved similar results to the animal behaviour data collected. This modelling methodology could easily be applied to interactions of other animal species. 相似文献
313.
Ying Hu Liu De Li Liu Min An Yin Lian Fu Ren Sen Zeng Shi Ming Luo Hanwen Wu Jim Pratley 《Ecological modelling》2009
Many plant species defend themselves against herbivorous insects indirectly by producing and releasing induced volatiles to attract natural enemies of the herbivores. In this paper, we consider the recruitment of natural enemies attracted by plant-induced volatiles and introduce the An–Liu–Johnson–Lovett model into the Lotka–Volterra model in an attempt to add this missing vital link in tritrophic interaction. Increase in attraction strength of plant-induced volatiles to the natural enemy leads to high fluctuation amplitude of plant biomass and herbivore population. When the attack strength of natural enemies reaches a certain level, fluctuation amplitude of plant biomass and herbivore population will decrease and plant biomass will approach to its environmental carrying capacity. The simulation demonstrates that plant volatile compounds induced by insects have led to the introduction of a third tritrophic level, e.g., natural enemies, into the plant–herbivore system, resulting in the coexistence of plants, insects, and natural enemies during the evolution process. 相似文献
314.
畜牧业的生产和发展推进了社会的发展,但同时也造成了生态环境的污染,给人类及其他生物的健康生存构成了很大威胁( 危害) ,况且这一问题已日趋突出。本文旨在介绍畜牧污染的危害及其特点,以期引起全社会的广泛关注,并提请有关方面给予高度重视 相似文献
315.
海河水生生态系统的研究 总被引:6,自引:0,他引:6
本文以调查,分析海河浮游植物,浮游动物,水生维管束植物和大型底栖重托 要生物群落现实结构为主系,系统分析了海河水生生态系统状况,结果表明,水体污染已经对海河水生生态系统产生了明显的有害影响。 相似文献
316.
The impact of heavy metal pollution gradients in sediments on benthic macrofauna at population and community levels 总被引:4,自引:0,他引:4
Ryu J Khim JS Kang SG Kang D Lee CH Koh CH 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):2622-2629
The effect of sediment pollution on benthos was investigated in the vicinity of a large sewage treatment outflow at Incheon North Harbor, Korea. Animal size, vertical distribution and standard community parameters were analyzed along a 3 km transect line (n = 7). Univariate parameters showed a general trend of increasing species diversity with increasing distance from the pollution source. Multi-dimensional scaling analysis led to the clear separation of 3 locational groups, supporting gradient-dependent faunal composition. The innermost location was dominated by small sub-surface dwellers while the outer locations by large mid to deep burrowers. Looking for the size-frequency distribution, most abundance species (Heteromastus filiformis) showed the presence of larger size animals with increasing proximity to the pollution source. Meanwhile, species-specific vertical distributions, regardless of the pollution gradient, indicated that such shifts were due to species replacement resulting from a higher tolerance to pollutants over some species. 相似文献
317.
Exponential Growth, Animal Welfare, Environmental and Food Safety Impact: The Case of China’s Livestock Production 总被引:1,自引:0,他引:1
Peter J. Li 《Journal of Agricultural and Environmental Ethics》2009,22(3):217-240
Developmental states are criticized for rapid “industrialization without enlightenment.” In the last 30 years, China’s breathtaking
growth has been achieved at a high environmental and food safety cost. This article, utilizing a recent survey of China’s
livestock industry, illustrates the initiating role of China’s developmental state in the exponential expansion of the country’s
livestock production. The enthusiastic response of the livestock industry to the many state policy incentives has made China
the world’s biggest animal farming nation. Shortage of meat and dairy supply is history. Yet, the Chinese government is facing
new challenges of no less a threat to political stability. Production intensification has created a welfare crisis impacting
the world’s biggest number of farm animals. The resulting food safety incidents are affecting consumer confidence and health.
Untreated waste contributes to the nation’s environmental degradation. Developmental states may have a proud record of growth
in the initial stage of industrialization. Their prospects for sustained development have long been questioned. China has
come to an important juncture to march towards a sustained development. 相似文献
318.
Konstantinos C. Makris Dibyendu Sarkar Stephan B.H. Bach 《Environmental pollution (Barking, Essex : 1987)》2009,157(6):1957-1960
Animal wastewater lagoons nearby concentrated animal feeding operations (CAFOs) represent the latest tendency in global animal farming, severely impacting the magnitude of greenhouse gas emissions, including nitrous oxide (N2O). We hypothesized that lagoon wastewater could be supersaturated with N2O as part of incomplete microbial nitrification/denitrification processes, thereby regulating the N2O partitioning in the gaseous phase. The objectives of this study were: (i) to investigate the magnitude of dissolved N2O concentrations in the lagoon; and (ii) to determine the extent to which supersaturation of N2O occurs in wastewater lagoons. Dissolved N2O concentrations in the wastewater samples were high, ranging from 0.4 to 40.5 μg N2O mL−1. Calculated dissolved N2O concentrations from the experimentally measured partition coefficients were much greater than those typically expected in aquatic systems (<∼0.6 μg N2O mL−1). Knowledge of the factors controlling the magnitude of N2O supersaturation could potentially bridge mass balance differences between in situ measurements and global N2O models. 相似文献
319.
Konstantinos C. Makris Syam S. Andra Dibyendu Sarkar Stephan B.H. Bach 《Environmental pollution (Barking, Essex : 1987)》2009,157(12):3508-3513
Concentrated animal feeding operations around the globe generate large amounts of nitrous oxide (N2O) in the surrounding atmosphere. Liquid animal waste systems have received little attention with respect to N2O emissions. We hypothesized that the solution chemistry of animal waste aqueous suspensions would promote conditions that lead to N2O supersaturation at the liquid/air interface. The concentration of dissolved N2O in poultry litter (PL) aqueous suspensions at 25 °C was 0.36 μg N2O mL−1, at least an order of magnitude greater than that measured in water in equilibrium with ambient air, suggesting N2O supersaturation. There was a nonlinear increase in the N2O Henry constants of PL from 2810 atm/mole fraction at 35 °C to 17 300 atm/mole fraction at 41 °C. The extremely high N2O Henry constants were partially ascribed to N2O complexation with aromatic moieties. Complexed N2O structures were unstable at temperatures > 35 °C, supplying the headspace with additional free N2O concentrations. 相似文献
320.
Linnea I. Laestadius Roni A. Neff Colleen L. Barry Shannon Frattaroli 《Environmental Communication: A Journal of Nature and Culture》2016,10(1):84-103
This paper examines the factors shaping non-governmental organization (NGO) messaging decisions on how meat consumption should be altered in light of climate change. In particular, we sought to understand the relative absence of messages promoting meat-free diets and the decision of some NGOs to pair meat reduction messages with messages encouraging consumers to switch to meat from ruminant grass-fed animals. Interviews were conducted with 27 staff members from environmental, food-focused, and animal protection NGOs from the USA, Canada, and Sweden. While strategic considerations consistently led to the use of modest messages for meat reduction, NGO missions were also key to shaping the specifics of messaging goals. The relatively low personal comfort levels that some NGO staffers held toward meat-free diets also led to the use of more modest requests for meat reduction. Findings highlight the complex nature of the factors underlying the environmental communication messages of NGOs. 相似文献