Mangroves in small islands are critical resources for the stability of the island and the livelihood of local coastal communities. However, scientific inventories of mangroves in small islands are rare due to their limited distribution. Considering this, the present study was conducted during 2014–2015 to determine the species composition, biomass, vegetative carbon stock and spatial distribution of mangroves at Neil Island, one of the small islands of the Andaman and Nicobar Islands, India. The spatial locations of different species of mangroves identified from our extensive field surveys were compared with high-resolution images, and the coverage of mangroves (genus level distribution) was interpreted entirely based on the elements of tone and texture. The results show that the mangroves of Neil Island consist of 17 true mangrove species belonging to 12 genera in eight families. The co-existence of all three Indo-West Pacific mangrove species of the genus Rhizophora ( Rhizophora apiculata , Rhizophora mucronata and Rhizophora stylosa ), and their hybrids ( Rhizophora × annamalayana , Rhizophora × lamarckii and Rhizophora × mohanii ) shows that this island is a unique place for studying the hybridization and speciation of Rhizophora , a worldwide dominant mangrove genus. Rhizophora mucronata was found to be the dominant species in terms of density, basal area and biomass estimated from forest structural assessments using the quadrat method. The mean density and basal area were 1162 trees ha −1 and 28 m 2 ha −1 , respectively. The mean above-ground biomass was 271 Mg ha −1 , while the mean below-ground biomass was 104 Mg ha −1 . The total mean biomass of Neil Island mangroves was 375 Mg ha −1 and its corresponding vegetative carbon stock was 171 Mg C ha −1 . The present study provides a practical approach to species-level mapping and assessment to gain site-specific knowledge of the mangroves of Neil Island. Since mangroves are vital for small islands such as Neil Island to cope with rising sea level and increases in natural calamities, the baseline scientific information provided by this study will be beneficial for Integrated Island Management.

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尼尔岛（印度安达曼和尼科巴群岛）的红树林区系、森林结构和制图，重点是红树属物种的多样性和小岛红树林的重要性

小岛上的红树林是岛上稳定和当地沿海社区生计的重要资源。然而，由于分布有限，小岛屿红树林的科学清单很少。考虑到这一点，本研究是在 2014-2015 年期间进行的，以确定印度安达曼和尼科巴群岛的小岛屿之一尼尔岛的红树林的物种组成、生物量、营养碳储量和空间分布。从我们广泛的实地调查中确定的不同红树林物种的空间位置与高分辨率图像进行了比较，并且完全基于色调和纹理元素来解释红树林的覆盖范围（属级分布）。结果表明，尼尔岛红树林由8科12属17种真红树种组成。红树属（Rhizophora apiculata , Rhizophora mucronata 和 Rhizophora stylosa ）的所有三种印度-西太平洋红树林物种及其杂交种（ Rhizophora × annamalayana 、 Rhizophora × lamarckii 和 Rhizophora × mohanii is a island ）的共存表明研究全球优势红树林属的 Rhizophora 杂交和物种形成的独特场所。在密度、基面积和生物量方面，用样方法对森林结构进行评估，发现红树是优势物种。平均密度和基面积分别为 1162 棵树 ha -1 和 28 m 2 ha -1 。平均地上生物量是 271 Mg ha -1 ，而平均地下生物量是 104 Mg ha -1 。尼尔岛红树林的总平均生物量为 375 Mg ha -1 ，其相应的营养碳储量为 171 Mg C ha -1 。本研究提供了一种实用的物种水平制图和评估方法，以获得尼尔岛红树林的特定地点知识。由于红树林对于尼尔岛等小岛屿应对海平面上升和自然灾害增加至关重要，因此本研究提供的基线科学信息将有利于岛屿综合管理。本研究提供了一种实用的物种水平制图和评估方法，以获得尼尔岛红树林的特定地点知识。由于红树林对于尼尔岛等小岛屿应对海平面上升和自然灾害增加至关重要，因此本研究提供的基线科学信息将有利于岛屿综合管理。本研究提供了一种实用的物种水平制图和评估方法，以获得尼尔岛红树林的特定地点知识。由于红树林对于尼尔岛等小岛屿应对海平面上升和自然灾害增加至关重要，因此本研究提供的基线科学信息将有利于岛屿综合管理。