全國中小學科展

地球與環境科學

Microfossil association of the Štíty locality

My thesis focuses on studying Cretaceous microfossil specimens from the excavation of former brickworks in Štíty, especially foraminifera. In the theoretical part, I have covered the structure of the Bohemian Cretaceous Basin area, especially Bystřice Lithofacial Development. I have also processed previous paleontological researches from the locality. Emphasis was placed on field research and subsequently on laboratory research of the site. I have examined the present state of the location and gathered samples of silt clay containing a wide variety of fossils. I have acquired the microfossils, determined them, and ordered them systematically. The most important part of the thesis is the systematic and palaeoecological processing of the collection of microfossils from the locality. The thesis continues the research of the last year of SOČ, where I have gathered a collection of fossil macrofauna, flora, and ichnofauna. My collection is supplemented mainly by benthic and planktonic foraminifers. I have confirmed that the specimens found are typical representatives of marine fauna belonging to the Upper Cretaceous Coniacian. The paleoecological characteristics of the locality correspond to a nutrient-rich shallow-water environment, occasionally disturbed by storm waves.

1910~2010年台灣附近板塊交界地帶地震能量觀察與比較

我們分析1910~2010年琉球及呂宋弧溝系統規模5.0以上的地震發生次數與能量釋放,並探討其特性。 經分析得知:(1)琉球系統地震發生次數及能量釋放變動不大。(2)將呂宋系統規模六地震大量發生的時間與規模七地震發生時間比對,發現1951及1999年部分規模六地震為規模七地震之餘震。若加入上述兩年規模六地震,則規模六地震大量發生之平均週期約為12年。(3)琉球系統能量大量釋放的週期約為30年,且其釋放的量越來越少。(4)呂宋系統大量釋放能量的週期約為十年。 (5)百年來,琉球系統的地震發生次數較呂宋系統多,在能量上則反之,還需深究是否為兩系統地質結構不同導致。(6) 若前次能量高峰釋放能量特別大,則距下次能量釋放高峰時間間隔較平均週期長。

強降雨對美崙溪河口沙洲之影響

美崙溪河口沙洲位於我們學校附近,其形貌常在大雨或颱風後明顯改變。這使我們好奇,決定研究大雨和颱風對沙洲的影響。我們在降水事件前後以GPS記錄並比較沙洲輪廓;挖取不同深度的樣本,藉由搖篩取得沉積物粒徑比例。得出以下結果: 一、降水事件前後,美崙溪河口沙洲北側沒有明顯的形貌變化,主因為鄰近之堤防位置,以及沿岸流與河流流向。 二、即使沙洲外貌沒有明顯變化,仍需藉由沉積物分析,方能確定沙洲是否改變。 三、中型降水事件,會使溪水漫過沙洲,造成沙洲中央礫石比例上升。 四、總雨量大於600mm之降水事件足以沖毀沙洲,但事件後沙洲快速復原。一般認為蜿蜒曲折的美崙溪理應流速較慢,但本研究發現強降水後河口沙洲變化急劇。

臺灣異常酸雨與鹼雨之時序分析與探討

從環保署2015~2017年報中,全國酸雨(pH值小於5.0)比例最高在萬里及觀音站,全國鹼雨(pH值大於6.1)比例最高在崙背站。經資料分析後,研究發現以下結論: 一、觀音站和萬里站皆為離海近且無當地污染源的背景站,因此酸雨污染源應是外來的;酸雨與PM2.5的形成方式有很高的關聯性,冬季的致酸汙染物可藉由東北季風到達臺灣,而使得酸雨發生比例高達90%。 二、崙背鹼雨與 [PM10-PM2.5] 的相關性最高,由緯向降水酸鹼值的變異分析發現當地局部地區的變遷很明顯,非外來環境影響所導致。 三、崙背北方的揚塵為雨水致鹼的原因之一,鹼雨發生比例高達90 %的月份皆在東北季風季,兩者雖非線性相關,但關聯性很高。 四、極端酸雨、鹼雨僅發生在時雨量小於 5 mm的事件。

探討單擺週期與潮汐、月地相對位置之關係

本實驗目的為測量重力加速度g值的變化情形,主要藉由量測單擺週期的大小變化,來推得重力加速度g值的隨月球方位及潮汐變化情形。國中知道同一地點的地表重力加速度g 值為定值,但根據參考文獻1,已知重力加速度g 值會受到環境因素影響而變化,甚至是會有週期性的變化,因此我們將測量單擺週期的微小變化來做驗證,實驗方法是透過筆電內的音效卡配合免費音效軟體Audacity,取樣頻率可達96000次/秒。實驗結果顯示對單擺週期的量測精確度可達0.0002秒,可以充分呈現單擺週期的影響因素。我們發現一日內月球的方位與潮汐皆會影響單擺週期的變化,且單擺週期之數據分布,與潮汐變化較為接近。故本實驗推論一日內單擺週期變化受潮汐影響大於月球的方位變化。

Removal of Nutrients by Chlorella Vulgaris Microalgae in Bandar Abbas Municipal Wastewater

The entry of nutrients into the environment can cause the creation of eutrophication of aquatic ecosystems. One of the methods of removing nutrients from effluents is the use of algae. Algal purification is a new and inexpensive technology for this purpose. The present study investigated the rate of cell growth and nutrient removal of urban wastewater in Bandar Abbas in winter 2020 by the Chlorella vulgaris microalgae in the phycolab of Fisheries Research. Treatments with different dilutions (0%, 25%, 50% and 75%) were prepared; in addition, specific growth rate, cell density and removal efficiency of phosphate, nitrate, nitrite were examined during a 14 day period with initial constant density (1×10⁶ cells / ml ) of microalgae. The results indicated that 0% and 75% dilution had the highest and lowest cell densities (8.675×10⁶ and 56.633×10⁶), respectively; moreover, they had the specific growth rate (0.166 and 0.311). Furthermore, there was a significant difference between them (P≥ 0.05). The highest nitrate and nitrite removal efficiencies were -40.75 and -79.84 in effluent dilution of 50%; in addition, the lowest were 1.26 and -40.26 in dilution of 75% and 25% respectively. Phosphate had the highest removal efficiency at 0% dilution with a mean of -79.65 that showed a significant difference with the lowest at 25% dilution (P≥ 0.05). Therefore, high or low levels of nutrients can affect the removal efficiency and growth rate of microalgae.

「震」「震」有詞--臺灣南部大陸隱沒帶地震發生之研究與探討

本研究分析位於台灣西南部東經120.5度、北緯21.7度地震群。數據顯示在1994-2017年6月間,於20-70公里深度處頻繁地出現地震,並且規模4.0以上的中大型地震好發於40km左右。資料顯示此地區地震發生和向西傾斜的張裂及走向滑移斷層關係密切,為說明聚合性板塊交界此種非聚合型低角度斷層的地震群的發生,我們利用一些模擬實驗和假設模型,解釋地震發生的空間規則,可能和板塊隱沒時應力施於交界處附近,使應力易累積於弱下部地殼與強上部地殼交界處有關,此模型在地震個數隨深度的分布與應力累積的空間分布均得到很好的證實。

Chlorella vulgaris chlorophyll a fluorescence as a potential indicator for zinc and nickel detection

Heavy metals contaminate many bodies of water, posing a health risk to not only organisms that live and use the water in these areas, but also to the humans that live nearby. Chlorella vulgaris, a microalga, is one organism whose chlorophyll a fluorescence can indicate the presence of these substances, detecting any changes in concentrations using fluorescence microscopy and other fluorescence devices. The study explores the sensitivity of C. vulgaris to the heavy metal zinc where the algae was exposed to five concentrations of zinc: 0 ppm, 5 ppm, 10 ppm, 50 ppm, and 100 ppm. The fluorescence of the samples was observed with a fluorescence microscope on days 0, 4, 7, and 12, where the algal samples were adapted to the dark for 5 minutes, then exposed to light for 90 seconds. The values of the minimal and maximal fluorescence of the samples in the dark were noted. There is a significant difference in the values of the minimal fluorescence, maximal fluorescence, and maximum quantum yield, a value derived from the minimal and maximal fluorescence, at the highest concentration, 100 ppm, from the other treatments for the entirety of the experiment. The significantly low values at 100 ppm and the calculated EC50 of 75.70 ppm indicate that C. vulgaris is indeed a viable indicator for zinc detection at this and higher concentrations of zinc.

從遙測看水色與紫外線及溫度之關聯

本研究使用NASA Ozone Watch南極臭氧濃度、MODIS Aqua之全球海平面水色、NOAA Operational SST Anomaly之均溫異常,以及Australian Antarctic Data Center南極葉綠素濃度數據,探討三大洋海洋水色的逐年變化以及影響因素。我們認為受到環境變遷的影響,影響水色最主要的外在因素可能為紫外線及溫度。本研究利用image J軟體,估算臭氧洞逐年的範圍變化,並利用水色換算出的葉綠素濃度的變化趨勢,將上述數據製作成圖比較。 結果顯示:在紫外線的部分,葉綠素濃度會隨著紫外線入射量減少而提高。在深度的部分,南極同一時間點所測數據顯示,水表到400公尺深的範圍中,呈現深度越淺葉綠素濃度越高的趨勢。此外,海表溫度正異常(>1.5°C)之面積分布,證實海水表面溫度變高時,葉綠素濃度變高,南極數據也顯示相同特徵。我們認為,生物基於避險本能,在紫外線過量時,生物會傾向往海洋深層移動;在10℃~35℃間,溫度越高,葉綠素濃度越高,影響浮游植物在深度的分布。上述各項皆能影響水色。

利用日光偏振訊息簡易計算觀測者所在經緯度之研究

研究利用日光偏振訊息找出太陽方位,發現ω(日光強度的極大值對稱軸旋轉角度)與太陽方位角As的關係為:As=-ω+φ,負號代表逆時針旋轉,φ為偏光膜初始角度。且驗證偏振度P和Z值之關係為P(θ)/Pmax=2Z-1,其中Z=1/(1+sin2((hs));任何時刻觀測由東向西的日光強度會呈雙峰變化,找出與峰值觀測方向夾90°的平面會通過太陽,進而求得太陽高度角hs。 採用三角定位法,以原地觀測不同時刻的太陽方位角,及太陽直射地球的經緯度,推算觀測者所在經緯度,若再輔以球面三角形法修正,可提高精確度。本計算模式在9時~15時的範圍內誤差約小於5°,比只能在正午時推算經緯度還來的便利。