台湾西南海域沉积物之自生重晶石富集与甲烷移栖之关系

台湾西南海域高甲烷通量的区域,有快速的硫酸盐还原速率,也伴随着高钡离子通量。藉由自生重晶石在沉积物中富集的深度,推估过去不同时期硫酸盐-甲烷反应带的位置,并利用自生重晶石富集峰的大小,计算其累积所需的时间,进而评估甲烷通量的迁移史。

向鸟学的功课

十月份我对中国进行了两个星期的访问,在这期间,我荣幸地成为中国基督教协会的座上宾客。主人们对我喜欢观察鸟类感到十分好奇,他们奇怪我怎么会进行这项活动的。答案乃在于我父亲,他是个心脏病医生,兴趣广泛,几乎涉及自然历史和科学的每一个分支,尤其是一个十足的业余植物学家。当我还只有六、七岁时,每逢学校放假,他总会带上我漫步在乡间,并且嘱咐我:闭上嘴,静静地用眼看,用耳听,那是一个极好的学习观察的方法。

Seasonal variation in abundance, diel vertical migration and body size of pelagic tunicate Salpa fusiformis in the Southern Yellow Sea

Mass occurrence of Salpafusiformis June 2007. In order to investigate its population was observed in the Southern Yellow Sea in May and recruitment and environmental adaptation, temporal variation of abundance, diel vertical migration （DVM） and length frequency distribution of both aggregate and solitary forms were studied with samples collected from eight months during September 2006 to August 2007. S. fusiformis presented in six months other than September and October 2006, and average abundance of aggregate and solitary forms peaked in June and May, respectively. In December, aggregate forms were absent in the bottom layer and performed irregular DVM from surface to 50 m depth, while solitary forms was too scarce to perform diel vertical distribution analysis. Both aggregate and solitary forms presented reverse DVM in May and June. They migrated upwards during daytime and concentrated in surface layer at sunset. The bimodal distribution of aggregate forms was found in April and the average size was largest in this month. In other months, the smaller aggregate forms （1-5 ram） dominated in populations except for May, when the modal size ranged from 2 to 8 mm. The average size of solitary forms was largest in December, followed by April. The skewed nomal distribution of solitary forms was found in May and June, with the modal size of 2-7 mm and 5-13 ram, respectively.

Geomorphic Habitat Type, Drift Cell, Forage Fish and Juvenile Salmon： Are They Linked？

The role of geomorphic habitat type, drift cell scale, and geographic scale in defining fish use of nearshore habitats is poorly known, particularly for Pacific salmon and their prey. In this study, key areas of nearshore habitat in central and western Strait of Juan de Fuca were categorized by geomorphic habitat type and assessed for fish use within a degraded （Elwha） and intact comparative drift cells over a one year period. Juvenile Chinook and coho salmon were also sampled for genetic analysis to define regional dispersal patterns. Key findings are： （1） Ecological function of the area＇s nearshore is complex, with very strong seasonal variation in fish use both within and across GMHT （geomorphic habitat type）; （2） GMHT link to nearshore function for fish use differs depending on the fish species and time of year. Surf smelt and sand lance were the most abundant. And they were seasonally used embayed, spit, and bluff shorelines more than lower rivers. Juvenile Chinook, coho, and chum salmon occurred in much lower density than forage fish species, and used lower rivers more than other GMHTs; （3） When GMHTs were combined and analyzed at the drift cell scale, the degraded drift cell had different ecological patterns than the intact drift cell; （4） Cross regional juvenile fish use of nearshore is an important component of habitat use： juvenile Chinook and coho from as far away as the Columbia River Oregon and Klamath River California utilize central Strait of Juan de Fuca shorelines. Forage fish species may do so as well. Drift cell and cross regional scales are therefore most important for accurately defining nearshore ecological function, management, and restoration actions.

Response of meiofaunal and nematode communities to sewage pollution abatement:a field transplantation experiment

To assess the recovery rate of meiofaunal and nematode communities upon abatement of sewage pollution, a field transplantation experiment was conducted in Tat Tam, which is a non-polluted, shallow subtidal habitat on the southern portion of Hong Kong Island. The sediments used were from one site located in Victoria Harbour that was heavily influenced by sewage pollution, and one site in the outside-harbor area, which was relatively clean. In addition, sediments from Tat Tam were used as a control. Fresh sediments with meiofauna were collected from the aforementioned sites, placed in plastic trays and transplanted to Tat Tam. Sediments were retrieved at the beginning of the experiment and at 1-, 3-, and 8-weeks after transplantation for analysis of the meiofaunal and nematode communities as well as the sediment characteristics. The results showed that the meiofaunal and nematode communities in the control sediments were consistent at the four sampling periods, while it took three and eight weeks, respectively, for the nematode communities from the outside-harbor and inside-harbor sites to become similar to the control. These findings indicated that the relatively poor habitat quality and the nematode community composition in the sewage polluted inside-harbor sediments required a longer time for recovery than samples from the better habitat quality and the nematode community composition in the outside-harbor sediments.

马来西亚观鸟:热带雨林中的百鸟乐区

作为西方国家十分盛行的一项户外活动,观鸟在美国已经成为了超越狩猎、钓鱼、高尔夫运动的全民运动。每年英国、丹麦、瑞典、法国、德国等国家都有数百万人观鸟。每逢假日,人们便相约而行,前往户外观赏野鸟。近年来,观鸟风潮刮向亚洲,有丰富鸟类资源的马来西亚,成了鸟类爱好者心中的新兴观鸟地之一。马来西亚一半以上的陆地都被热带雨林所覆盖,从滨海的红树林到云雾缭绕的深山雨林,马来西亚丰富的热带环境资源使这里成为了各种鸟类栖息的乐园。又因地处澳大利亚鸟类移栖的必经之路,大马也成为了众多候鸟的第二家园。