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Biology Presentation Date : 04 December 2008. Introduction. Introduction. Introduction. Introduction. Introduction. Introduction. Introduction. In the densely populated city of Hong Kong, waste is a troublesome issue.
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Biology Presentation Date : 04 December 2008
Introduction Introduction Introduction Introduction Introduction Introduction
Introduction • In the densely populated city of Hong Kong, waste is a troublesome issue. • The city generates around 6.4 million tons of waste each year, and in eight years' time, its existing landfills are expected to be full. • The government has introduced waste management schemes and delivered education to the public. • On the commercial side, producers are taking up measures to reduce waste.
Introduction • Land Pollution • Noise Pollution • Light Pollution • Water Pollution - Oil Pollution • Case Study : - Water Pollution in Hong Kong
土地污染 Land Pollution Land Pollution Land Pollution 土地
農業Agriculture • 泥土的重要性 • 含有多樣化的營養 • 主要來自有機物,但植物不能直接吸收有機物,要靠微生物將之分解 • 人工合成的化學肥料,只能集中提供個別養份 • 植物需要從泥土中吸收其他養份,始能茁莊成長 • 植物不斷從泥土吸收養份,但養份又不能得到全面補給 • 泥土會變得越來越瘦脊,倚賴更多的化學肥補充,造成惡性循環
農業 Agriculture • 1.化學肥料Chemical Fertilisers • 化肥 - 無生命的化學劑 • 不能給泥土中的生物 提供有機物 • 失去泥土的黏附力 • 在下雨或刮風時,表面土粒容易被沖走或吹走,令土地逐漸不能再種植
農業Agriculture • 2. 農藥 Pesticides • 化學農藥有毒害,殘留土壤中會毒害環境 • 連泥土中的生物也殺掉,令養份循環受阻 • 引致害蟲產生抗藥性 • Example : 「滴滴涕」(DDT)
工業Industry • 工業生產過程排出大量含有危害生物健康的化學廢料 • 電子產品丟棄之後會釋出毒物 • 回收處理這些廢料又要使用其他化學劑,結果造成新的毒物
解決方法Solution • 1. 焚毀垃圾 • 焚燒垃圾的過程中把熱轉化為能量 • 2. 回收再造 • 使垃圾減少被堆填和焚燒, 幫助降低污染 • 水流中有害物質被清除後, 我們的健康及環境均可受保護 • 因為我們減少利用未經加工的原料, 所以循環再用使我們的天然資源得到保護 • 據估計, 廢紙再用這個方法每年能保存200,000棵樹木 • 與用新資源製成的產品比較, 回收再造可把生產所需要的能量及由95% 減到64%, 並且能減低相關的95%空氣污染
解決方法Solution • 3. 減低廢物 • 購買東西之前, 應想清楚是否真的需要這件東西 • 購買大量的貨品, 將會減去對每件貨品的額外包裝 • 統計每星期拋掉的膠袋總數, 將之減少1/3 • 帶備可循環再用的容器去餐廳吃飯,把剩餘的食物帶回家中,比用發泡膠容器為佳 • 去商店購物時,攜帶自己的購物袋 • 假若我們願意去減少使用物品, 使能保留更多產品避免它們被送去堆填及焚燒 • 我們可以降低對新產品的需求, 從而能幫助減低砍伐森林, 開採天然資源, 空氣及水的污染
解決方法Solution • 4.重新使用 • 捐贈書本, 唱片及雜誌給本地的圖書館,書舖,音響店,學校(送給兒童及作教學資源) • 捐贈衣服及家居用品給慈善機構, 孤兒院或保存給下一代 • 很多容器及蓋子均可用作美術設計的物料 • 重新使用禮物的包裝紙, 利用兒童所繪畫的圖畫, 雜誌,報紙,漫畫作為包裝禮物的材料 • 重新使用商店的膠袋作為垃圾袋或作為儲藏物件之用
噪音污染 Noise Pollution Noise Pollution Noise Pollution 噪音
噪音的定義 • 噪音是強烈的 • 雜亂無章 • 令人覺得煩躁 • 干擾我們收聽想聽到的聲音 • 過響聲、妨礙的、不愉快的聲音
噪音的定義 • 噪音類別 • 工業噪音 • 交通噪音 • 家庭噪音 • 一個人連續八小時處身於聲級達85分貝的噪音環境, • 極可能對聽覺造成損害 • 嚴重甚至會患上精神病
噪音對我們生活的影響 • 噪音對健康有很大的影響 • 損害聽覺系統的神經細胞不斷死亡,使聽力逐漸下降 • 噪音和振動亦會破壞視覺系統,導致對視野的分辨率改變 • 對藍色和綠色的光視野增大,對金色及紅色的光視野縮小,影響視覺清晰度 • 引起頭暈、頭痛、失眠、容易疲倦、煩躁及造成心理壓力 • 損害循環系統,影響心跳速度及血壓 • 噪音更會引致食慾不振、消化不良等消化系統毛病 • 影響人思考問題、影響人工作、影響學生讀書 • 使人享受不到正常的生活樂趣、享受不到健康和諧的家庭生活、影響與朋友的溝通和聯絡 • 降低效率,令人注意力分散,容易發生意外,導致死亡
噪音的量度 • 0分貝 耳朵能夠聽到 • 10分貝 農村的靜夜 • 20分貝 樹葉落地 • 30分貝 耳邊輕聲低語 • 50-60分貝 普通說話聲 • 80分貝 公共汽車上 • 110分貝 電鋸旁邊 • 140-150分貝 飛機旁
人類對噪音的反應 • 60分貝時有50%的人會從睡眠中驚醒 • 60分貝以上就要捂著耳朵 • 75分貝很難與他人對話 • 85分貝時根本聽不到對方的說話
噪音問題的改善 • 香港政府在部份公路及天橋設置隔音屏 • 於1989設立噪音管制條例 • 噪音管制條例管制範圍: • 家庭噪音 • 工業噪音 • 機種的使用 • 交通噪音 • 19:00後不准打樁 • 23:00後不可在家中喧嘩
光污染 Light Pollution Light Pollution Light Pollution 光
光污染Light Pollution • 一種因過度使用人為室外照明,而對自然環境和生態等引起的負面影響 • 根據香港大學物理系2003年起的研究統計,香港市區的夜空,比起人口稀少的郊野地區,已被光害嚴重污染了超過三十倍 • 影響 • 1. 生態2. 人體3. 天文觀測
如何減少光害 • 減少使用不必要的室外照明 • 留意室外照明的設計 • 選用有利天文觀測的光源 • 節省能源 • 改裝現有的室外照明 • 截光型燈具的設計 非截光型燈具的設計
Water Pollution Water Pollution Water Pollution Water Pollution 水
1. Definition of Water Pollution • Addition of undesirable materials into aquatic bodies • Leading to different harmful effects • Becoming less favourable for humans and other organisms
2. Source of Water PollutantsA. Pollution in Flowing Streams and Rivers • Release of inorganic and organic substances • Chemicals from industries • Sewage from urban areas • Animal wastes, pesticides and fertilisers from farmland
2. Source of Water PollutantsB. Pollution in Coastal Areas • Example : Beaches, Wetlands, Mangrove, Delta regions, Estuaries, etc. • Industrial wastes and urban sewage without treatment.
3. Types of Water Pollutants • Oxygen-demanding wastes • Human sewage • Manure of livestock • Water-soluble inorganic chemicals • Acids and Salts • Toxic heavy metal ions e.g. Hg+.
3. Types of Water Pollutants • Inorganic nutrients • Chemical fertilisers • Organic nutrients • Domestic, agricultural and industrial wastes • Oil, plastics, pesticides and detergents
3. Types of Water Pollutants • Sediment • Insoluble soil particles suspended in water • Hot effluent - Hot water discharged from factories and power stations.
4A. Agricultural Wastes • Animal Wastes • Causing water pollution when washed into rivers. • They can be decomposed by bacteria aerobically. • Large population of bacteria will be developed if the concentration of these pollutants is high. • Lower the water quality and threaten aquatic life. • Some organisms in wastes cause diseases e.g. dysentery, when polluted water is drunk by human.
4A. Agricultural Wastes • Inorganic Fertilisers and Pesticides • Chemicals in fertilisers & pesticides are toxic. • Accumulation of toxic chemicals along the food chain. • Inorganic nutrients in fertilisers are water soluble. • They enhance eutrophication and causing algal bloom. • This threatened the aquatic life.
4B. Domestic Wastes • Sewage • Sewage released from home containing dung, urine and dirty water. • The decomposition of organic wastes in sewage consumes large amount of oxygen. • The oxygen demand rises rapidly and dissolved oxygen in water drops suddenly. • Sewage contains nutrients which can be used by algae and other micro-organisms for reproduction and growth. • The growth of bacteria and algae will take up a lot of oxygen from water and cause aquatic organisms to die of suffocation. • More oxygen will be consumed when algae are decomposed by bacteria when they die.
4B. Domestic Wastes • Detergents • Many detergents are non-biodegradable and persist in water to mix with water. • Foams are formed to prevent light passing through to reduce the rate of PHS of algae and plants. • Foams prevent the entry of oxygen from the atmosphere so that the amount of dissolved oxygen in water drops. • Some detergents are biodegradable. • Algae bloom will be resulted because detergents contain high phosphate (PO4) content.
4C. Industrial Wastes • Chemicals • Chemicals like cyanides and soluble heavy metal ions like lead are produced from electroplating. • These pollutants usually discharged directly into water are poisonous to aquatic life. • Their concentration increase along the food chains and become toxic enough to kill or harm high level organisms.
4C. Industrial Wastes • Hot Water • Hot water is produced by factories and power stations. • Increasing the water temperature • Reducing the solubility of oxygen in water • Aquatic organisms die of suffocation
5. Examples of Control Measures of Water Pollution in Hong Kong
1. Controlling Pollution at Source • ‘The Water Pollution Control Ordinance’ came into effect in 1980. • Discharge of effluent is subject to control under the ‘Water Pollution Control Ordinance’. • Operators are required to ensure that the levels of toxic and harmful substances in industrial sewage meet the standard set by EPD. • The Government has divided the whole territory into 10 ‘Water Control Zones’, where a license is needed for disposal of effluent other than sewage.
2. Adopting well-planned sewage treatment schemes • The Government put forward ‘The Harbour Area Treatment Scheme’ to collect and treat the sewage from urban areas around Victoria Harbour. • There are over 10 sewage treatment works for treating sewage. The largest one is on Stonecutters Island. • Livestock Waste Control Scheme is carried out. • The Government collects sewage charges from those who discharge sewage, under the ‘Polluter Pay’s Principle’, in order to discourage the sewage discharge.
http://hk.youtube.com/watch?v=il4k7VHUMF8 Advertisement of theHarbour Area Treatment Scheme 淨化海港計劃宣傳片
The Harbour Area Treatment Scheme • An overall sewage collection and treatment scheme for areas on both sides of Victoria Harbour. • Stage 1 of HATS involved the construction of a 23.6 km-long system of tunnels deep underground • Carrying 1.4 million tones of sewage from Kowloon and NE Hong Kong Island to sewage treatment plant on Stonecutters Island. • Water quality in the Victoria Harbour substantially improved when Stage 1 was commissioned.
The Harbour Area Treatment Scheme • The Government has divided the whole territory into 10 Water Control Zones. • 1. Victoria Harbour • 2. Tolo Harbour and Channel • 3. Junk Bay • 4. Deep Bay • 5. Mirs Bay • 6. Port Shelter • 7. Southern • 8. North Western • 9. Eastern Buffer • 10. Western Buffer
The Harbour Area Treatment Scheme Changes in Water Quality since the commissioning of HATS • E. coli • Dissolved Oxygen • Ammonia (NH4) • Inorganic Nitrogen
Water Pollution Water Pollution Oil Pollution油污染 Water Pollution
油污染Oil Pollution • 部份由油輪漏出到海的原油引起 • 揮發性碳氫化合物有毒性,令生物致命 • 覆蓋海鳥的羽毛,失去天然保護能力和浮力,因體熱流失死亡和溺死 • 海鳥清理羽毛時吞食有毒性的原油而受傷或死亡 • 積聚在魚類的鰓,失去呼吸能力,繼而死亡 • 油污掩蓋水面, 減少水中溶解氧的含量