Mangrove Forest Structure in the São João River Estuary, Rio de Janeiro, Brazil

Despite the low tree diversity and scarcity of the understory vegetation, the high morphological plasticity of mangrove trees induces, at the stand level, a very large variability of forest structures that need to be mapped for assessing the functioning of such complex ecosystems. Fully constrained linear spectral unmixing (FCLSU) of very high spatial resolution (VHSR) multispectral images was tested to fine-scale map mangrove zonations in terms of horizontal variation of forest structure. The study was carried out on three Pleiades-1A satellite images covering French island territories located in the Atlantic, Indian, and Pacific Oceans, namely Guadeloupe, Mayotte, and New Caledonia archipelagos. In each image, FCLSU was trained from the delineation of areas exclusively related to four components including either pure vegetation, soil (ferns included), water, or shadows. It was then applied to the whole mangrove cover imaged for each island and yielded the respective contributions of those four components for each image pixel. On the forest stand scale, the results interestingly indicated a close correlation between FCLSU-derived vegetation fractions and canopy closure estimated from hemispherical photographs (R2 = 0.95) and a weak relation with the Normalized Difference Vegetation Index (R2 = 0.29). Classification of these fractions also offered the opportunity to detect and map horizontal patterns of mangrove structure in a given site. K-means classifications of fraction indeed showed a global view of mangrove structure organization in the three sites, complementary to the outputs obtained from spectral data analysis. Our findings suggest that the pixel intensity decomposition applied to VHSR multispectral satellite images can be a simple but valuable approach for (i) mangrove canopy monitoring and (ii) mangrove forest structure analysis in the perspective of assessing mangrove dynamics and productivity. As with Lidar-based surveys, these potential new mapping capabilities deserve further physically based interpretation of sunlight scattering mechanisms within forest canopy.

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Impact of wood harvesting on mangrove forest structure, composition and biomass dynamics in India

Estuarine Coastal and Shelf Science ◽

10.1016/j.ecss.2020.106974 ◽

2020 ◽

pp. 106974 ◽

Cited By ~ 2

Author(s):

Dina N. Rasquinha ◽

Deepak R. Mishra

Keyword(s):

Forest Structure ◽

Mangrove Forest ◽

Wood Harvesting ◽

Biomass Dynamics

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Palynological reconstruction of environmental changes in coastal wetlands of the Florida Everglades since the mid-Holocene

Quaternary Research ◽

10.1016/j.yqres.2015.03.005 ◽

2015 ◽

Vol 83 (3) ◽

pp. 449-458 ◽

Cited By ~ 16

Author(s):

Qiang Yao ◽

Kam-biu Liu ◽

William J. Platt ◽

Victor H. Rivera-Monroy

Keyword(s):

Coastal Wetlands ◽

Mangrove Forest ◽

Environmental Changes ◽

River Estuary ◽

Florida Everglades ◽

Loss On Ignition ◽

Proxy Record ◽

Peat Deposits ◽

Increasing Precipitation ◽

Mangrove Communities

Palynological, loss-on-ignition, and X-ray fluorescence data from a 5.25 m sediment core from a mangrove forest at the mouth of the Shark River Estuary in the southwestern Everglades National Park, Florida were used to reconstruct changes occurring in coastal wetlands since the mid-Holocene. This multi-proxy record contains the longest paleoecological history to date in the southwestern Everglades. The Shark River Estuary basin was formed ~ 5700 cal yr BP in response to increasing precipitation. Initial wetlands were frequently-burned short-hydroperiod prairies, which transitioned into long-hydroperiod prairies with sloughs in which peat deposits began to accumulate continuously about 5250 cal yr BP. Our data suggest that mangrove communities started to appear after ~ 3800 cal yr BP; declines in the abundance of charcoal suggested gradual replacement of fire-dominated wetlands by mangrove forest over the following 2650 yr. By ~ 1150 cal yr BP, a dense Rhizophora mangle dominated mangrove forest had formed at the mouth of the Shark River. The mangrove-dominated coastal ecosystem here was established at least 2000 yr later than has been previously estimated.

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KONDISI HUTAN BAKAU TEBANGAN MASYARAKAT DAN INDUSTRI PULP DI BATU AMPAR KALIMANTAN BARAT

Jurnal Kawistara ◽

10.22146/kawistara.7590 ◽

2015 ◽

Vol 5 (2) ◽

Author(s):

Tjut Sugandawaty Djohan ◽

P.M. Laksono ◽

Esti Anantasari ◽

Angga N. Utama ◽

Krisni Suhesthiningsih

Keyword(s):

Species Diversity ◽

Mangrove Forest ◽

River Estuary ◽

Local People ◽

Mangrove Species ◽

Pulp Industry ◽

Mangrove Tree ◽

Rhizophora Apiculata ◽

Bruguiera Gymnorhiza ◽

Tree Cutting

The purpose of this research was to study tree cutting of mangrove forest by the local people of Batu Ampar and the pulp industry at Kapuas river estuary. At each site the rapid measurement methods were established using quadrate plots of 20m x 20m and 5m x 5m, each with 2 replicates. The results revealed that the local people only cut the selective trees of Rhizophora apiculata and Bruguiera gymnorhiza with diameter of 20-25 cm2 at 0.25 ha wide, which created gap canopy as small disturbace to the mangrove forest. This area of gap canopy immediately was colonized and dominated by R. apiculata. The mangrove tree cuttings created the phase gap generations. This forest recovered quickly, thus the small distrurbance maintained the mangrove tree species diversity. The Rhizophora roots were habitat for nusery grown of larval shrimps, crabs, and fishes. The pulp industry cut all of the mangrove species wich created big disturbance and huge gap area. The forest also recovered quickly, but was dominated by Xylocarpus granatum. Thus, the big disturbance by the pulp industry caused the shifted species of the mangrove forest species from Rhizophora and Bruguiera to Xylocarpus. The roots of Xylocarpus tree were not habitat forthelarval shrimps, crabs, and fishes, which decreased the fisherman catch. The forest rehabilitation of industrial cutting was planted regularly with Rhizophora, and created many current canals which proned to the erosion. Thus the pulp industry of mangrove forest cutting threatened nursery habitat and species diversity at the mangrove forest of Batu Ampar.

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Ichthyofauna of Sungai Merbok Mangrove Forest Reserve, northwest Peninsular Malaysia, and its adjacent marine waters

Check List ◽

10.15560/17.2.601 ◽

2021 ◽

Vol 17 (2) ◽

pp. 601-631

Author(s):

Danial Hariz Zainal Abidin ◽

Sébastien Lavoué ◽

Norli Fauzani Mohd Abu Hassan Alshari ◽

Siti Azizah Mohd. Nor ◽

Masazurah A. Rahim ◽

...

Keyword(s):

Mangrove Forest ◽

River Estuary ◽

Alpha Diversity ◽

Taxonomic Diversity ◽

Peninsular Malaysia ◽

Fish Diversity ◽

Marine Waters ◽

Forest Patch ◽

Forest Reserve ◽

Aquatic Biodiversity

Sungai Merbok Mangrove Forest Reserve, encompassing the Merbok river estuary, was established as a permanent forest reserve in 1951 and is the second-largest intact mangrove forest patch in Peninsular Malaysia. Despite its importance, few studies have been conducted to assess its aquatic biodiversity. In this study, we surveyed the fish diversity of the Merbok river estuary, and its adjacent marine waters. We recorded 138 fish species belonging to two classes, 18 orders, 47 families, and 94 genera. The richest order is Perciformes, with 32 recorded species, represents 23% of the alpha diversity, followed by Carangiformes with 21 recorded species or 14% of the diversity. Low taxonomic diversity overlaps with previous inventories and indicates that the inventory is still incomplete. All specimens examined are catalogued and deposited in a local museum collection. The fish checklist presented here represents a step forward in the conservation of fish diversity in the Merbok river estuary.

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