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Environmental, soil and tree variables of mangrove forests in Gazi Bay examined between August and October 1999
Citable as data publication
Obade P.T.; De Wulf R.; Tack J.; Ecological Marine Management Programme (ECOMAMA). VUB; Laboratory of Forest Management and Spatial Information Techniques; Faculty of Agricultural and Applied Biological Sciences. Ugent; Laboratory of Ecology and Systematics; Faculty of Science. VUB: Belgium; (2016): Environmental, soil and tree variables of mangrove forests in Gazi Bay examined between August and October 1999. https://doi.org/10.14284/116
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Availability: Creative Commons License This dataset is licensed under a Creative Commons Attribution 4.0 International License.

Description
This dataset contains measurements of pH, salinity, T, grain size, abundance (%), organic matter (%), tree diameter (CBH (cm)) and tree height (m) of mangrove forests of Rizophora mucronata in Gazi Bay examined between August and October 1999. The data were digitized by VLIZ from the original report: Obade, P.T. (2000). Anthropogenically induced changes in a Kenyan mangrove ecosystem explained by application of remote sensing and Geographic Information System (GIS). MSc Thesis. RUG: Gent. 65 pp. more

Six carefully selected sites were sampled, 3 disturbed and 3 undisturbed sites. Random quadrats were chosen per site with at least 30 adult trees, that is, with tree diameters at breast height (DBFD of at least 2.5 cm. All locations were marked using a Garmin 80 model Global Positioning System (GPS). For salinity, temperature and pH, 3 holes per site were dug, each of approximately 10 cm depth using a corer with a diameter of 6 cm, and panga to obtain replicate readings for interstitial water. An optical refractometer, Atago brand, was used to determine the salinity, while temperature and pH readings were obtained using a WTW pH 320/set-1 brand of pH meter. A nylon rope was used to measure the circumference at breast height (CBFD which may be converted to DBH using the formula DBH:CBF/π. A Recta compass with clinometer was used to measure the tree height. The corer scooped soil samples, from 3 locations, were divided into 5 approximately equal layers (10-8, 8-6, 6-4, 4-2,2-0 cm in depth) each per site. These were packed in pre-labeled plastic bags and carried to the Gazi field station laboratory. The samples were oven dried at 60°C in the laboratory. They were then stored in labelled plastic bags for granulometric analysis conducted at the Royal Belgian Institute of Natural Sciences (KBIN, Brussels). At KBIN, approximately 20 grams of each sample were scooped using a spatula and their exact weight determined, Crushing was at times necessary to loosen the soil particles. The organic matter in the samples were removed following the method of Wartel et al., (1995) using 30% diluted technical H2O2 as an oxidizing agent. The samples were then wet sieved through a 75-pm sieve using a Fritsch analysette to separate the coarse from the fine fraction. After ensuring that there were no floccules, a sedigraph was used for final analysis (according to Stoke's law).

Scope
Themes:
Biology > Plants, Bottom samples (e.g. core, dredge, grab)
Keywords:
Marine/Coastal, Geographical information systems, Mangrove forests, Satellite imagery, Soil analysis, ISW, Kenya, Coast, Gazi Bay, Rhizophora mucronata Poir.

Geographical coverage
ISW, Kenya, Coast, Gazi Bay [Marine Regions]

Temporal coverage
23 August 1999 - 10 October 1999

Taxonomic coverage
Rhizophora mucronata Poir. [WoRMS]

Parameters
Depth
Grain size distribution
Organic matter (OM)
pH
Salinity
Temperature

Contributors
Vlaams Instituut voor de Zee (VLIZ), moredata manager
Vrije Universiteit Brussel; Faculteit Wetenschappen; Vakgroep Biologie; Ecological Marine Management Programme (ECOMAMA), moredata creator
Universiteit Gent; Faculteit Bio-ingenieurswetenschappen; Vakgroep Omgeving; Laboratory of Forest management and spatial information techniques (FORSIT), moredata creatordata creator
Vrije Universiteit Brussel; Faculteit Wetenschappen; Vakgroep Biologie; Laboratorium voor Ecologie en Systematiek (ECOL), moredata creatordata creator

Project
ECOMAMA: Ecological Marine Management, more

Publication
Based on this dataset
Obade, P.T. (2000). Anthropogenically induced changes in a Kenyan mangrove ecosystem explained by application of remote sensing and Geographic Information System (GIS). MSc Thesis. RUG: Gent. 65 pp., more

Dataset status: Completed
Data type: Data
Data origin: Research: field survey
Metadatarecord created: 2013-11-18
Information last updated: 2016-11-09
All data in the Integrated Marine Information System (IMIS) is subject to the VLIZ privacy policy