保護紅樹林是全球性的保育運動。貝里斯的紅樹林主要分佈於沿海地帶，且擁有高密集度分佈。貝里斯市紅樹林主要種類有三種：低矮紅樹科樹種(Rhizophora Mangle)、偏黑的海茄苳屬樹種(Avicennia Germinans)、及高大且白的假紅樹屬樹種(Laguncularia Racemosa) 。不過沿著濕地邊界或是深入內陸地區的溪流或沼澤可發現些許的紐仔樹數種(Conocarpus erectus) 。紅樹林因具有胎生的性質，且能適應海水的環境，故提供了許多水禽生物及海棲生物的生存場所。
本研究主要運用衛星影像及地理資訊系統探討位於貝里斯河(Belize River)及席本河(Sibun River)流域的紅樹林分佈情形。主要研究地區範圍約為9,495公頃，北至貝里斯河上的可樂華橋(Haulover Bridge)，南至席本河流域。這地區的紅樹林面臨極大的破壞壓力，在人類的快速都會開發、土地濫墾、旅遊發展以及全球暖化的影響下，這些地區除了直接面臨開發命運外，河川及海岸的污染也直接衝擊紅樹林生態。年雨量是主要威脅紅樹林生態的重要因素，年雨量的多寡影響土壤及流域中含鹽量的濃度，進而影響紅樹林分佈及物種組成。本研究使用Landsat衛星資料日期為1989/12/27、 2000/01/24以及2010/01/11。運用這20年間的衛星影像來分析紅樹林的分佈及減少情況。研究方法運用非監督式分類法將衛星影像進行分類。Landsat衛星影像進行非監督式分類結果，1989年總精準度為80%，2000得到77%，2010得到74% 。研究方法另運用變遷偵測來進行時間分析，以瞭解紅樹林分佈的改變。變遷偵測分析結果顯示，1989年至2000年間紅樹林面積平均減少11%，而2000年至2010年間紅樹林面積則減少幅度提高至15%。
整體而言，在1989年至2010年主要研究地區內紅樹林面積減少幅度高達26%。這顯示在貝里斯，紅樹林面積正急速減少。本研究建議應有適當政策及組織來保護貝里斯市周圍的紅樹林面積及數量，以減少紅樹林砍伐及開發情形，藉由本研究希望可提高重視紅樹林自然環境的保護意識，為貝里斯留下寶貴的自然資產 。

Mangrove forests lie along the coast of Belize and one of the largest concentrations of mangroves is located around Belize City. Mangrove forests in this area consists of three types which are mainly short red mangrove (Rhizophora Mangle), medium black mangroves (Avicennia Germinans) and tall white mangroves (Laguncularia Racemosa) although the existence of buttonwood (Conocarpus erectus) can be found along the boundaries of wetlands, streams or swamps deeper inland. Mangrove forests on the coast of Belize provide estuaries for fishes and sanctuaries for birds. Mangrove forests of the study area are located within the Belize and Sibun river water sheds. The mangrove ecosystem in this area faces the threat of deforestation from rapid urban development, land reclamation, increase in tourism and natural disasters (global warming). Other major threats include changes in rainfall patterns which could affect distribution and species composition because rainfall regulates salt concentrations in soil and plants, as well as providing a source of fresh water for the mangroves (Neal et al., 2008).
The area being studied lies between Haulover Bridge on the northern boundary and Sibun River on the southern boundary which covers an area of approximately 9495.52 hectares. The objective of this study is to use GIS and remote sensing analysis of December 27th, 1989, January 24th, 2000 and January 11th, 2010 Landsat images to verify that mangrove deforestation has been occurring over a period of 20 years. The method of unsupervised classification was applied to this study. Temporal analysis by using change detection was carried out to monitor change detection. Overall classification accuracy of 80% was obtained for 1989 Landsat image, 77% overall classification accuracy was obtained for 2000 Landsat image and 74% overall classification accuracy was obtained for 2010 Landsat image.
Results obtained for temporal analysis by using change detection showed that mangrove forests declined by an average of 442 hectares (26%) over a 20 year period. During 1989 to 2000 mangrove forests declined by 207 hectares (11%) and during 2000 to 2010 mangroves declined by an average of 235 hectares (15%). Over a period of 20 years short mangroves increased by 86 hectares (5%), medium mangroves decreased by 857 hectares (49%) and tall mangroves decreased by 557 hectares (34%). This study shows that mangrove forest is rapidly declining and needs to be addressed urgently to deter further destruction on this valuable habitat.

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