北京香山公园自然景观价值二十年变迁

自然景观是由自然环境、物质和景象构成,具有观赏、游览、休闲、疗养等效用和价值的风景综合体或景物。然而,人们在开发利用自然资源时,并没有将自然景观的价值纳入到费用效益分析中,这种对自然景观价值的忽略和低估导致了各种不可逆转的环境问题。如果赋予自然景观合适的经济价值并探究其价值变化,能为其开发利用提供决策支持。以北京香山公园为例,构建了价值评估的指标体系:即自然景观价值为使用价值与非使用价值之和。并对这两种价值分别运用个体旅行费用法和条件价值法进行评估,得出2012年香山公园的使用价值为19.25亿元,非使用价值为3.46亿元。对香山公园在1992—2012年20年间的自然景观价值变化进行深入的研究发现,其景观价值由1992年的0.175亿元增长到2012年的22.71亿元,增长近130倍,速率为1.13亿元/a,游客量的加倍增长、人们游览支出的提高,以及支付意愿的增长是产生该变化的主要原因。随着环境污染和生态破坏的日益加剧以及人们对健康生活的迫切向往,香山公园自然景观价值仍将持续增长,景区当局应全面认识香山公园所承载的价值,在发展旅游的同时也要积极探索解决现有生态环境问题的新思路。     

Large-scale two-photon calcium imaging in freely moving mice

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Persistent activity in limbic system neurons: neurophysiological and modeling perspectives

Neural activity persisting for one to hundreds of seconds has been postulated to be a substrate of memory. This review article illustrates examples of such activity in limbic system structures including the hippocampus, postsubiculum, and the anterodorsal thalamus. These neuronal responses include better known correlates with the spatial position as well as with head direction of the animal relative to its environment as well as other lesser known examples. Since head direction responses are greater when the animal is actively moving than when passively rotated, it has been proposed that there might be a general mechanism where the behavioral state of the animal can provide modulatory gating of such persistent signals. This would regulate the relative influence of these signals on downstream structures. Neural network attractor models of the head direction cell system are presented to demonstrate how these responses might originate, as well as the dynamics by which they are updated during movements.     

Migration success and migration time of gastrically radio-tagged v. PIT-tagged adult Atlantic salmon

Adult Atlantic salmon (55–116 cm total length) with PIT-tags ( n = 318) and both PIT-tags and gastric radio-tags ( n = 127) in a regulated river showed similar upstream migration success, yet radio-tagged fish migrated faster than fish with only PIT-tags. Regurgitation rate of radio-tags was 9%.     

Long-term home range stability provides foraging benefits in western gorillas

Objectives

Long-term home range stability presumably emerges because familiarity with an area improves fitness through increased foraging efficiency, reduced predation risk, or reduced costs of intergroup aggression. While the use of spatial memory by primates has been widely demonstrated, few studies have examined whether long-term space use creates opportunities for interannual reuse of spatial knowledge. Here we examine the ranging behavior of western gorillas (Gorilla gorilla) to assess the degree of long-term site fidelity and the foraging consequences of reuse of space.

Methods

We measured interannual home range overlap over a 10-year period for a single group of gorillas at the Mondika Research Center, using both grid-based and kernel density estimation. By plotting the total area used over time, we identified periods of home-range stability and expansion. We compared foraging and ranging behavior in familiar versus unfamiliar areas, considering fruit trees visited, dietary diversity, and daily path length, to determine whether the lack of spatial knowledge in unfamiliar areas was associated with foraging costs.

Results

Average interannual home range overlap by the group remained high throughout the study. During periods of home range expansion, daily path lengths increased but not the number of fruit trees visited, suggesting that reduced familiarity with the area led to decreased foraging efficiency because individuals lacked prior knowledge of where to find resources.

Discussion

Western gorillas at Mondika exhibit long-term home range stability, presumably reflecting a strategy that relies on the use of spatial memory to increase foraging efficiency that is favored by their reliance on ephemeral fruit resources.

     

The future of future-oriented cognition in non-humans: theory and the empirical case of the great apes

One of the most contested areas in the field of animal cognition is non-human future-oriented cognition. We critically examine key underlying assumptions in the debate, which is mainly preoccupied with certain dichotomous positions, the most prevalent being whether or not ‘real’ future orientation is uniquely human. We argue that future orientation is a theoretical construct threatening to lead research astray. Cognitive operations occur in the present moment and can be influenced only by prior causation and the environment, at the same time that most appear directed towards future outcomes. Regarding the current debate, future orientation becomes a question of where on various continua cognition becomes ‘truly’ future-oriented. We question both the assumption that episodic cognition is the most important process in future-oriented cognition and the assumption that future-oriented cognition is uniquely human. We review the studies on future-oriented cognition in the great apes to find little doubt that our closest relatives possess such ability. We conclude by urging that future-oriented cognition not be viewed as expression of some select set of skills. Instead, research into future-oriented cognition should be approached more like research into social and physical cognition.     

A neural code for egocentric spatial maps in the human medial temporal lobe

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Geographic comparison of seasonal migration events of the large white butterfly,Pieris brassicae

1. The multivoltine butterfly Pieris brassicae (Linnaeus) inhabits most climatic zones in Europe and Asia. Its regional populations are adapted to the respective climatic conditions and hibernate in those regions. Yet how these adaptations are stabilised in spite of the species' regular migration events is unclear. 2. In this study, significant differences were found in the preferred flight direction of P. brassicae depending on the season and the butterfly's geographic origin. The individual flight behaviours indicated that flight direction is a heritable character. 3. The bivoltine population from northern Germany undertook a typical return flight in the second generation of the year. This reverse flight was induced by the developmental mode of the caterpillars. A diapause in the pupal stage triggered a northward migration, and a non‐diapause a southward migration. 4. In contrast to bivoltine populations, the second generation of multivoltine populations maintained the direction of the hibernating generation. 5. A unique situation was determined for the population from the northern coast of Spain. The North Sea seemed to be a migration barrier that forced an adaptation, with the first generation flying southeastward, and the second generation northeastward. 6. The flight pattern of at least some of the investigated populations suggests that, after their yearly migration, the descendants of a local population are able to reach the home range of their ancestors again.