雨水衝擊和土壤滲透速率關係之探討
This research is devoted to researching the influence of rain-drop impact on the rate of infiltration. Rain-drop simulators 160cm tall drip water into a transparent container (14 x 10 x 4) of three kinds of soil (quartz sandstone, loess, sand soil) Through the manipulation of factors such as rain impact (raindrop diameter, raindrop descendent height, frequency of impact) and soil property, we experiment the different possibilities of infiltration and its rate under various conditions. Through this comparison we aim to discover the relation between rain impact and infiltration rate. This research concludes the following: 1. The larger the diameter of the raindrop, the quicker the infiltration rate. 2. The greater the descendent height, the greater the speed of infiltration due to collected descending speed. 3. In the early stage of rain, the greater the frequency of rain impact, the faster the rate of infiltration. 4. Under controlled raining conditions, the larger blank sand soil allows greater infiltration speed. 5. In the later stage of rain impact, a blanket of water accumulates on the surface of the soil, reducing the impact force and thus affecting the rate of infiltration. 本研究試探究雨滴撞擊對土壤入滲速度所造成的影響，針對此問題設計下列方法，以進行探討。我們採用高160cm 的自製雨滴模擬器來滴濺長14cm，寬10cm、高4cm 的透明實驗盒裝入三種土樣（石英砂、黃土與黑砂壤），接著改變各種雨水衝擊因子（不同直徑的水滴、不同的落下高度、不同的撞擊頻率）和土壤條件（土壤性質…）等變因，讓滴濺過程產生不同的情形，滴濺過後再行滲透作用，比較各情況所造成的滲透速率快慢的差異，尋找出雨滴衝擊和土壤滲透速率的關係。本研究有以下幾點結論：1. 雨滴粒徑愈大，對於土壤的入滲速率愈快。2. 雨水落下高度愈大時，因水滴動能的增加，土壤的入滲速率也愈快。3. 在水滴撞擊的初期，當水滴滴落頻率愈大時，土壤的入滲速率也會愈快。4. 當雨滴條件相同時，平均粒度較大的黑砂壤其入滲速率較快。5. 在雨滴撞擊後期，因表層土壤產生的水膜造成雨滴撞擊能量的變化。當水膜厚度愈大時，撞擊產生的能量有減少的趨勢而影響了土壤的入滲速率。
台灣地形對颱風路徑的影響
颱風是台灣地區常見的天然災害之一，而台灣地區複雜的地形變化，也為颱風路徑的變化投下一個變數。根據以往的資料顯示，颱風路徑受到地形影響往往是在登陸前六小時內，而颱風對台灣地區災害最嚴重的時候往往是登陸前後三小時，也就是說要是颱風路徑受到地形影響發生偏轉，則我們只有數小時的時間來進行防災的準備。本研究主要收集1987~2001年由台灣東部登陸的台風最佳路徑圖，分別統計其颱風路徑或颱風環流過山時的變化，並分類統計各種不同颱風要素（包括颱風強度、行進速度、移入角、登陸地段等）對颱風路徑變化的影響，以做為未來預報之參考。結果顯示，台灣地形的確對颱風路徑有所影響，並使颱風在接近時偏轉，偏轉角度大多在30度以內，且偏北較偏南略多。而當颱風已偏東北方向接近時（移入角小於60度）向南偏轉較多；以偏東南方向接近時（移入角大於161度）方向偏較多，顯然地形對颱風行進有阻礙作用；而正交颱風偏轉角度也比斜交颱風小。在颱風強度部分，越強的颱風路徑偏轉角也越小，颱風過山後路徑受到導引氣流影響回到原路徑的機率較低。而影響颱風移動速度最主要的因素是導引氣流的強弱，若導引氣流受到山脈阻擋時，會使颱風移動速度減慢。而台灣各地山脈高低不同，也會使某些地區出現較特殊的台風現象。例如花蓮南部及成功地區容易誘發副低壓造成分裂路徑；台東地區因颱風容易繞山而過因此偏南機率比其他地區高等。Typhoon is a natural hazard that often occurs in Taiwan. The complex terrain of Taiwan also adds to the uncertainty to typhoon tracks. Based on past data, typhoons often show changes in their tracks within six hours before making landfall, while they produce most of their damage within three hours of the landfall. In other words, if the track of a particular typhoon was to be affected by the terrain, people have only a few hours to prepare. The study collects best tracks of a total of 145 typhoons that made landfall from the east of Taiwan from 1987 to 2001. Their tracks and changes in circulation while they moved across the Central Mountain Range are recorded, and classified according to several different elements such as strength, traveling speed, incipient angle, and landfall area. The possible influence of these elements on typhoon tracks can be applied to forecasts in the future. Results indicate that the terrain of Taiwan does have an impact on typhoon tracks, and causes typhoons to turn when they approach from the east. Turning angle in most cases is within 30°, and cases turning northward are slightly more than those turning southward. When typhoons approach Taiwan from the northeast (incipient angle 160°) they favor turning north. Also, the turning angle tends to be smaller for typhoons that approach the terrain at a right angle, and the opposite is favored when the incipient angle is more acute. This suggests that the terrain of Taiwan had a blocking and deflecting effect to typhoon tracks. For results related to typhoon strength, stronger typhoons tend to exhibit smaller turning in their tracks, but they are also less likely to return to their original direction of motion under the influence of steering flow after they leave the terrain. The most relevant factor to moving speed of typhoon is the strength of steering flow, which is slowed down if blocked by the terrain. The difference in terrain elevation can also influence the motion of typhoon and cause some rather special phenomena. For instance, a secondary low is more likely to form and result in a discontinuous track if a typhoon made landfall over southern Hwa-Lien or Cheng-kung, while a typhoon has a higher possibility to be deflected southward if it made landfall over Tai-tung, the southernmost area.
台灣西部沿海地區海水倒灌的問題探究
海水倒灌一直是台灣西南沿海地區居民揮之不去的夢靨，所以本研究的目的即根據資料了解西南沿海地區的地質、地勢、現況以及參考專家分析造成海水倒灌的可能因素後，因此設計了【模擬沿海地區海水倒灌的模型箱】，再進行【超抽地下水會導致地層下陷及海水入侵的實驗】、【了解地下水鹽化灌溉農作物的生長情形】，最後企圖找出農作物鹽化的即時處理及土壤鹽化恢復的方法，還有利用太陽能以低壓簡易蒸餾的方式模擬海水淡化的可行性，希望能解決海水倒灌的後遺症問題。Inwelling is a problem which has affected the inhabitants of the coastal regions of Southwest Taiwan for many years. This study examines the geological and topographical structure of the coastal regions of Southwest Taiwan, and considers experts’ views on the possible causes of inwelling. This information is used as the basis for designing a box for modeling inwelling in the coastal regions, experimentation to study land subsidence and inwelling caused by excessive extraction of groundwater, and examination of the impact on crop growth of irrigation using groundwater which has been affected by salinification. Finally, the study seeks to find methods for dealing promptly with the salinification of agricultural crops and for the remediation of salinified soil. In addition, solar energy is used (with a simple, low-pressure distillation method) to model the feasibility of desalinifying seawater in the region in question, in the hope that this will help to remedy some of the aftereffects of inwelling.
台灣和東亞地區的氣候變遷
由人類活動造成的溫室效應可能導致地球溫度升高,聖嬰現象加劇等現象與災害,本文利用個氣候中心發展出的模式,推估台灣和東亞地區未來氣候變遷的情況,我們發現當大氣中的二氧化碳濃度增加為現在的1.9倍時,台灣地區的年平均溫度將升高0.85-2.50度C而東亞地區將會升高1.46-4.07度C,在同條件下個模式的平均推估量也顯示,台灣地區將每天增加0.10公厘的降水，而東亞地區每天將增加0.08公哩,我們希望這個研究結果可以做為其他相關研究的基礎,使大家提早因應未來氣候變遷所可能引發的種種變化;Greenhouse effect, incurred mainly by human activities may result in lots of phenomenon and damages such as the increasing of the world's average temperature and he aggravation f the "ElNino" effect. In this research, we simulate future metrological values by employing several simulation modes developed by different climate centers and predict future climate changes in Taiwan and East Asia area. We found that when the concentration of carbon dioxide exceeds 1.9 times than current value, the estimated range of the increased year-average temperature are0.85-2.5℃ and 1.46-4.07℃ for Taiwan and East Asia, respectively. Under the same condition, the ensemble mean reveals that the precipitation raises will be 0.1 and 0.08mm per day, for Taiwan and East Asia respectively. We hope our work can be the foundation of other related researches, and all the researches together can help for coping with possible damages caused by future climate changes.
臭氧事件日-氣象與地形對臭氧於近地大氣層之生成與傳輸影響
2001、2002 年監測資料被用以探討風場、時間、地形對臭氧傳輸影響。完成沿海地區與盆地內各二次採樣分析，探討各污染物與風場之垂直變化，及地面臭氧分布與風場變化。結果顯示各月份與全年之日間，其相對濕度與O3 相關度最高，日照次之。提高濕度，最能抑制[O3]。夜間NO 與O3 的相關度最高，濕度次之。臭氧事件日時：(1).11:00 即可產生高臭氧，(2).沿海地區在臭氧事件日仍保持低[O3]， (3).盆地效應改變風場，使近山地區[O3]居高不下，(4).因處O3 不斷被吹入，沿海地區傍晚時之[O3]下降速度減緩。臭氧事件日之O3 生成速率R 與消失速率常數L 被求出，其中14:00 後之R 與L 值均由正值轉負值，顯示大氣反應型式明顯轉變。R 與L 值在14:00∼15:00 間最小，係因O3 反應生成光化學煙霧所致。16:00 後另一低R 與L 值，則可能導因O3 與微粒或水份反應。分析結果顯示：(1).污染物會隨高程而略增，最高濃度在300∼500 m 處，(2).各高程大氣均可分析出73 種主要HC，其隨高度之分布被繪出與探討，(3).低層大氣會有較多低分子量HC，而高層大氣則有較多高分子量HC。結果亦顯示： (1).盆地內[O3]、[NO]與[NO2]不僅較沿海地區高，且於各高程之變動亦較大，(2).沿海地區THC、烷、烯類均較高，且隨高程增加而增高，但在盆地內則相反，(3).二地區各高程之鹵化物、芳香族、氧化物與其他有機物之平均濃度相近，但沿海地區之濃度變動較大。探討O3 之二傳輸現象獲知：(1).風吹向盆地內時，[O3]隨風向遞增，R 與L 會由12:00 之正值，轉為14:00 之負值；(2).風由盆地內外吹時，[O3] 隨風向遞減，R 與L 值提前於12:00 即為–202.561 與–1.621，但14:00 時R 與L 值增大為–76.411 與0.244， (3).風向並非決定[O3]的主要因素，地形與環境因素才是。實驗結果證實：(1).不同HC 會影響O3 之生成與消失，(2).改變[NO]o 對[O3]影響不大，但高[NO]會使得[O3]下降略緩，(3).降低HC 與[NOx]雖可使 [O3]略降，但提高濕度最能抑制[O3]，(4).在O3 的衰減量上，[O3]隨濕度增加而快速降低，但衰減率則隨[O3]o 的增加而降低。一個臭氧之統計模式被建立，臭氧與水反應速率常數與速率式也被求出。
The monitoring data were used to investigate the effect of surface wind, time, and terrain on the transformation of ozone. The sampling and the analysis in the coastal and in Taichung basin were completed. The vertical distribution of O3, NOX and HC and the different altitude wind were investigated. The contour of O3 and surface wind with 3D map were plotted. The results show that the correlation behaves relativity of relative humidity with ozone is the best, and solar radiation is the next. Enhancing environmental moisture can efficiently decrease ozone concentration. In each ozone event day are: (1) the high [O3] always starts from 11:00, (2) the ozone concentration on the coastal is always low due to the high humidity, (3) the high [O3] in the east of the basin is due to the basin effect which causes changes the surface wind, and (4) in the evening, the descend rate of [O3] in the coastal area is lower because ozone blows into the coastal area. The formation rate (R) and disappear rate constant (L) of the ozone event day were obtained. The values of R and L change from plus to minus before 14:00. The values of R and L are lower at 14:00∼15:00 due to the photochemical smog formation. And another lower R and L value before 16:00 may be due to ozone react with particle or water. The results of analysis indicate that: (1) the concentration increases with increasing altitude, and the maximum is at 300∼500 m height, (2) 73 kinds of hydrocarbons were identified, and the concentration variation with altitude was also investigated, and (3) most of low molecular weight HC are at lower altitude, otherwise high molecular weight HC are at higher altitude. The results also show that: (1) [O3], [NO], and [NO2] on the basin are not only lower than on the coastal, but also their variability of concentration are big, (2) THC, paraffins, and olefins on the coastal are higher than on the basin, and the concentrations increase with increasing altitude on the coastal, but on the basin is decreasing, (3) the average concentrations of halides, aromatics, oxides, and others are similar on both area, but concentration variability on the coastal is obvious. Two types of O3 transformation was investigated, the phenomenon indicts that: (1) when wind blew into the basin, [O3] increased with wind direction. The value of R and L change from positive (12:00) to negative (14:00); (2) when wind blew out of the basin, [O3] decreased with wind direction. The more small value of R (−202.561) and L (−1.621) appeared at 12:00 earlier. But the value of R and L will become bigger to –76.411 and 0.244; (3) ozone concentration does not just dependent on wind direction., topography and surrounding conditionsa are more important effect. The experimental results show that: (1) ozone formation or disappearance depends on different HC, (2) the effect 2 of [NO]o is small for ozone photochemical reaction, but [O3] decreases with increasing [NO], (3) the descend rate of O3 depends on high humidity more than different kinds of HC or [NO], and (4) the descend amount of ozone increases with increasing humidity strongly, and the descend rate of ozone decreases with enhancing [O3]o. A statistical model was developed. The reaction rate and rate constant of ozone reaction with water were also obtained.
台灣桃園縣虎頭山的泥裂痕的分析和研究
桃園虎頭山是位於林口台地南端的低海拔(約240~260M)丘陵地,表土層屬於紅土層,紅土主要成分為細沙(直徑>50μm，約佔50%)、粉沙(直徑2~50μm，約佔30%),其餘以黏土為主,加上少量含鐵礦物,採樣地點字圖二中的三聖宮旁的登山步道,其坡面面向東南方,對位處北緯25度的桃園屬於向陽波,經日曬適當時間後所產生的龜裂現象,是我們探討的對象;We have focused the study on the sun cracks found in the Mts.Hu-To are located in the southern part of the Mesa Lin Kou, which are 240m to 260m above the sea level. Mainly red clay, the surface soil is a composition of fine sand(diameter>50μm,up to50%)and silt(diameter>2~5 μm,up to 30%),including clay and a limited amount of iron minerals. The soil sample was gathered at the trail beneath the Hil Gue-Lun(241m,see pic.1)from the southeastern latitudes.