Composition, biomass and structure of mangroves within the Zambezi River Delta
- 646 Downloads
We used a stratified random sampling design to inventory the mangrove vegetation within the Zambezi River Delta, Mozambique, to provide a basis for estimating biomass pools. We used canopy height, derived from remote sensing data, to stratify the inventory area, and then applied a spatial decision support system to objectively allocate sample plots among five strata. Height and diameter were measured on overstory trees, saplings and standing dead trees in nested plots, and biomass was calculated using allometric equations. Each of the eight mangrove species occurring in Mozambique exist within the Delta. They are distributed in heterogeneous mixtures within each of the five canopy height classes, not reflecting obvious zonation. Overstory trees averaged approximately 2000 trees ha−1, and average basal area ranged from 14 to 41 m2 ha−1 among height classes. The composition of the saplings tended to mirror the overstory, and the diameter frequency distributions suggest all-aged stands. Above-ground biomass ranged from 111 to 483 Mg ha−1 with 95 % confidence interval generally within 15 % of the height class mean. Despite over 3000 trees ha−1 in the small-tree component, 92 % of the vegetation biomass is in the overstory live trees. The objective inventory design proved effective in estimating forest biomass within the 30,267 ha mangrove forest.
KeywordsForest inventory Mangrove biomass Zambezi River Delta
Dr. Wenwu Tang, Univ. North Carolina—Charlotte, conducted the geospatial analyses for the stratified random sampling design, and developed the Spatial Decision Support System for objective allocation of sample plots. Denise Nicolau, Itelvino Cunat, and Rito Mabunda provided invaluable logistical support during the planning and implementation of field missions. Célia Macamo and Salamão Bandeira assisted prior to, and during field work, with identification of mangrove and other plant species. The success of this project would not have been possible without the hard work and dedication of the 2012 and 2013 mission field crews. This work was made possible by US AID support to the USFS under the US AID Mozambique Global Climate Change Sustainable Landscape Program, in collaboration with the Natural Resource Assessment Department of the Government of Mozambique.
Funds for this work were provided by the US Agency for International Development and the US Dept. of Agriculture, Forest Service.
- Beentje H, Bandeira S (2007) Field guide to the mangrove trees of Africa and Madagascar. Kew Publishing, SurreyGoogle Scholar
- Beilfuss RD, Moore D, Bento C, Dutton P (2001) Patterns of Vegetation Change in the Zambezi Delta, MozambiqueGoogle Scholar
- Cochran WG (1977) Sampling techniques, 3rd edn. Wiley, New York, p 428Google Scholar
- Densham PJ (1991) Spatial decision support systems. In: Maguire DJ, Rhind DW (eds) Geographical Information Systems: Prinicples and Applications. Wiley, New York, pp 403–412Google Scholar
- GRID-Arendal (2013) Atlas of the changing environment—Zambezi River Basin. http://www.grida.no/graphicslib/detail/zambezi-river-basin-average-temperature_8c75
- Howard J, Hoyt S, Isensee K, Pidgeon E, Telszewski M (eds.) (2014) Coastal blue carbon: methods for assessing carbon stocks and emissions factors in mangroves, tidal salt marshes, and seagrass meadows. Conservation International, Intergovernmental Oceanographic Commission of UNESCO, International Union for Conservation of Nature. Arlington, Virginia, USAGoogle Scholar
- Institute SAS (2011) SAS/STAT 9.3 User’s Guide. SAS Institute Inc., Cary, North CarolinaGoogle Scholar
- Kauffman JB, Donato DC (2012) Protocols for the measurement, monitoring and reporting of structure, biomass and carbon stocks in mangrove forests. Center for International Forestry Research, BogorGoogle Scholar
- Smith TJ (1992) Forest Structure. pp 101–136 In: Robertson, A.I. & Alongi, D.M., (eds.), Tropical mangrove ecosystems. Coastal & Estuarine Studies #41, American Geophysical Union, Washington, D.CGoogle Scholar
- Vilankulos M, Marquez MR (2000) Physical characterization of the coastal zone of mangrove areas in the districts of Dondo and Marromeu, Sofala, based on interpretation of aerial photographs, vol 1. Direcçao Nacional de Florestas e Fauna Bravia, MaputoGoogle Scholar
- World Agroforestry Center (2013) Wood density database. http://worldagroforestry.org/regions/southeast_asia/resources/wood-density-database