基于旅游生态足迹模型的东山岛旅游可持续发展评价

根据旅游生态足迹的理论、方法以及研究进展,在生态足迹模型的基础上,构建旅游交通、旅游住宿、旅游餐饮、旅游购物和旅游观光等5个子系统所组成的旅游生态足迹模型,计算分析东山岛2005年旅游生态足迹,并与当地居民生态足迹进行比较。结果表明:东山岛2005年旅游生态足迹为4.6183gha,人均生态足迹是当地居民的2.98倍。各子系统人均生态足迹从大至小依次为旅游餐饮0.00390gha,旅游交通0.003848gha,旅游观光0.003165gha,旅游住宿0.00123gha和旅游购物0.00042gha。     

基于旅游生态足迹模型的东山岛旅游可持续发展评价

根据旅游生态足迹的理论、方法以及研究进展，在生态足迹模型的基础上，构建旅游交通、旅游住宿、旅游餐饮、旅游购物和旅游观光等5个子系统所组成的旅游生态足迹模型，计算分析东山岛2005年旅游生态足迹，并与当地居民生态足迹进行比较。结果表明：东山岛2005年旅游生态足迹为4.6183gha，人均生态足迹是当地居民的2.98倍。各子系统人均生态足迹从大至小依次为旅游餐饮0.00390gha，旅游交通0.003848gha，旅游观光0.003165gha，旅游住宿0.00123gha和旅游购物0.00042gha。     

海南岛农业土地资源可持续利用

本文分析了海南岛农业土地资源利用的优势与制约因素 ,论述了农业土地资源的特点 ,指出了农业土地资源可持续利用的对策。     

Developmental stress affects the attractiveness of male song and female choice in the zebra finch (Taeniopygia guttata)

Developmental stress has recently been shown to have adverse effects upon adult male song structure in birds, which may well act as an honest signal of male quality to discriminating females. However, it still remains to be shown if females can discriminate between the songs of stressed and non-stressed males. Here we use a novel experimental design using an active choice paradigm to investigate preferences in captive female zebra finches (Taeniopygia guttata). Nine females were exposed to ten pairs of songs by previously stressed and non-stressed birds that had learned their song from the same tutor. Song pairs differed significantly in terms of song complexity, with songs of stressed males exhibiting lower numbers of syllables and fewer different syllables in a phrase. Song rate and peak frequency did not differ between stressed and non-stressed males. Females showed a significant preference for non-stressed songs in terms of directed perching activity and time spent on perches. Our results therefore indicate that developmental stress affects not only the structure of male song, but that such structural differences are biologically relevant to female mate choice decisions.     

Vocal interactions in common nightingales (<Emphasis Type="Italic">Luscinia megarhynchos</Emphasis>): males take it easy after pairing

Seasonal patterns of bird song have been studied intensively with a focus on individual males. However, little is known about seasonal patterns of singing during vocal interactions between males. Vocal interactions have been shown to be important in sexual selection as males may signal aspects of motivation or quality. Here, we investigated in nightingales (Luscinia megarhynchos) whether a male’s behaviour in vocal interactions at different stages of the breeding season is influenced by its mating status. We examined how males that differ in their subsequent mating success respond to a non-interactive, nocturnal playback presented during the period of mate attraction and subsequently during the egg-laying period. We found that mated males overlapped fewer songs and had a lower song rate during the egg-laying period compared to their responses during the mate-attraction period, whereas unpaired males did not vary in their responses between the two periods. Our results suggest that mating status is a key factor affecting singing behaviour in vocal interactions and that a time-specific singing pattern like song overlapping is used flexibly during vocal interactions. Because song overlapping is thought to be a signal of aggression in male–male vocal interactions, it seems that males vary the level of aggression in vocal interactions according to their mating status and to the stage in the breeding season.     

Detecting Population Declines over Large Areas with Presence-Absence, Time-to-Encounter, and Count Survey Methods

Abstract:  Ecologists often discount presence-absence surveys as a poor way to gain insight into population dynamics, in part because these surveys are not amenable to many standard statistical tests. Still, presence-absence surveys are sometimes the only feasible alternative for monitoring large areas when funds are limited, especially for sparse or difficult-to-detect species. I undertook a detailed simulation study to compare the power of presence-absence, count, and time-to-encounter surveys to detect regional declines in a population. I used a modeling approach that simulates both population numbers and the monitoring process, accounting for observation and other measurement errors. In gauging the efficacy of presence-absence surveys versus other approaches, I varied the number of survey sites, the spatial variation in encounter rate, the mean encounter rate, and the type of population loss. My results showed that presence-absence data can be as or more powerful than count data in many cases. Quantitative guidelines for choosing between presence-absence surveys and count surveys depend on the biological and logistical constraints governing a conservation monitoring situation. Generally, presence-absence surveys work best when there is little variability in abundance among the survey sites, the organism is rare, and the species is difficult to detect so that the time spent getting to each survey site is less than or equal to the time spent surveying each site. Count surveys work best otherwise. I present a case study with count data on the Northern Flicker ( Colaptes auratus ) from the North American Breeding Bird Survey to illustrate how the method might be used with field-survey data. The case study demonstrates that a count survey would be the most cost-effective design but would entail reduction in the number of sites. If this site reduction is not desirable, a presence-absence survey would be the most cost-effective survey.     

海南岛热带农业光能资源利用率研究

本文通过绿色植物能量转化的生理机能,即光合作用过程中太阳能的投入、转化和产出的内在联系,定量地描述了海南岛各地实际光能利用率;地区性农业生产潜力;潜在光能利用率及其与实际光能利用率的绝对差值。结果表明,全岛实际光能利用率低于全国平均水平,只及一年两熟地区的一半,高值区接近一年一熟地区;潜在光能利用率与世界热带地区差距不大;潜在与实际光能利用率之差全岛平均达5.1％,具有较大的增产潜力。文中还针对海南的实际粗略地探讨了岛内光能利用率不高的原因和提高光能利用率的相应途径。     

化学防除薇甘菊对内伶仃岛土壤原生动物群落的影响

在化学防除薇甘菊过程中，对薇甘菊施加不同浓度除莠剂森草净前后两个月内土壤中原生动物群落的种类组成及数量动态变化进行了研究．实验发现施加除莠剂森草净后，肉足虫的种类数及丰度均随着施药浓度的增大而下降，且丰度变化尤为剧烈；低施药浓度下(m=0．001gm^-2)鞭毛虫及纤毛虫的种类数均有所增加；鞭毛虫的丰度随施药浓度增大而急剧增大．结果表明：除莠剂森草净对土壤原生动物群落有较大的影响，在两个月后依然有可能破坏土壤生态环境进而影响土壤肥力及动植物的生长。     

Size-based predation by kookaburras (Dacelo novaeguineae) on lizards (Eulamprus tympanum: Scincidae): what determines prey vulnerability?

Lizards and birds are both popular ”model organisms” in behavioural ecology, but the interactions between them have attracted little study. Given the putative importance of birds as predators of diurnal lizards, it is of considerable interest to know which traits (of lizards as well as birds) influence the outcome of a predatory attempt. We studied predation by giant terrestrial kingfishers (kookaburras, Dacelo novaeguineae: Alcedinidae) on heliothermic diurnal lizards (highland water skinks, Eulamprus tympanum: Scincidae), with particular reference to the role of prey (lizard) size. Our approach was twofold: to gather direct evidence (sizes of lizards consumed in the field, compared to those available) and indirect evidence (size-related shifts in lizard behaviour). We quantified the size structure of a natural population of skinks (determined by an extensive mark-recapture program), and compared it to the sizes of wild lizards taken by kookaburras (determined by analysis of prey remains left at the birds’ nests). Kookaburras showed size-based predation: they preyed mainly on small and medium-sized rather than large lizards in the field. However, the mechanism producing this bias remains elusive. It is not due to any distinctive behavioural attributes (locomotor ability, activity level, habitat usage) of the lizards of the size class disproportionately taken by the kookaburras. The greater vulnerability of subadult lizards may reflect subtle ontogenetic shifts in ecological and behavioural traits, but our data suggest that great caution is needed in inferring patterns of vulnerability to predation from indirect measures based on either the prey or the predator alone. Instead, we need direct observations on the interaction between the two. Received: 30 May 2000 / Revised: 29 July 2000 / Accepted: 26 August 2000     

生态旅游资源管理中社区参与激励机制探讨--以厦门岛东海岸区生态旅游开发为例

以厦门岛东海岸区 (黄厝 )生态旅游开发为例 ,提出在生态资源开发、管理过程中 ,实现社区公众有效参与、社区居民的生活水平得到提高的同时 ,达到生态保护目的的保障机制———生态旅游股份合作制。进而就厦门岛东海岸区生态旅游股份合作制运行框架进行了探讨。