IAPRS & SIS, Vol.34, Part 7, "Resource and Environmental Monitoring", Hyderabad, India, 2002 
  
primary and secondary data collected through field survey at 
the selected stations in the Sundarbans. GIS softwares 
(IRDAS and ArcView) and satellite image were applied to 
interpret the results. 
SAMPLE COLLECTION 
Two of the major mangrove species in the Sundarbans are 
Rhizophora mucronata and Avicennia marina. Hence, they 
were chosen for the study. Different parts of plants can 
absorb metal with varying efficiency. The main objective of 
this study was to find out the rate of dbsorption of iron (Fe), 
zinc (Zn) and copper (Cu) by different parts of these two 
plants. Metal concentration was analysed in root, stem, leaf, 
bud, seed, soil, and sediments near the root and general 
sediment at an average 3m distance from the root. The two 
types of soils were collected to determine the rate at which 
root absorbs metals. It is assumed that root will mainly 
absorb metal from its immediate vicinity. 
Sediments samples ware collected with the aid of cleaned 
and dried sediment corers. Sediment sub samples were 
transferred from the corer to clean polythene containers with 
plastic spatula. Different vegetative parts (root, stem, leaf, 
bud and seeds) of plant samples were collected from 
mangrove species of Rhizophora apiculata and Avicennia 
marina. Generally, from each station and parts, ten samples 
were collected. They were thoroughly washed with distilled 
water and were placed in polythene bags and transported to 
the laboratory in icebox. Samples were dried separately at 
110°C. Similar samples were mixed together after drying 
and homogenized before acid digestion. 
For extraction of copper, zinc and iron, improved acid 
digestion procedure was adopted as described by Walting 
(1981). The white residue formed after acid digestion was 
then redissolved in 10% V/V nitric acid and the metals 
concentration was determined using ICP Spectrometer 
(Parkin and Elmer). 
STEPS INVOLVED IN THE IMAGE PROCESSING 
The following steps were covered in image processing: 
Digitization of base map with the plotting of already existing 
Latitude Longitude Points 
(base map was obtained from Survey of India toposheet) 
Selection and identification of station in the satellite derived 
map with points icon comparing with toposheet map. 
y 
Verifying those point of interest with Global Positioning 
System instrument (GPS) 
Creating Identification number (ID) for each station in the 
map 
y 
Incorporating heavy metals data in table against each station 
J 
Preparation of graphs (bar diagram for Rhizophora and pie 
diagram for Avicennia) for each station and each metals separately 
regarding flow of heavy metals (Cu, Zn & Fe) in Rhizophora and 
Avicennia plants and sediments 
(by application of ArcView software). 
Preparation of final layout 
1) putting north arrow. 
2) Positioning pointers 
Final print out (Figure 1, 2) 
(two printout regarding the distribution of Cu, Zn and Fe in 
Rhizophora and Avicennia plants are taken here). 
RESULTS 
Maximum concentration of zinc (Zn) was found in Avicennia root 
soil in station 2 (66.3ug/g). In parts of Avicennia, leaf had 
maximum concentration of 20.9ug/g., compared to root and stem 
(Figure 3). 
In the case of Rhizophora plant, bud was having maximum Zn 
concentration, which was estimated to be 28.2ug/g and the lowest 
concentration was found in the stem (2.32pg/g) in station 1. 
In both the plants, stem had less concentration of Zn (7.78 ug/g in 
Rhizophora and 4.155pg/g in Avicennia) than root and upper parts 
in the other stations too. Generally, in all the cases root soil was 
having much higher concentration than plant parts. 
In the case of copper, distant sediments in all the three stations 
were having nearly same concentration (20.9ug/g to 22.3 ug/g) 
(Figure 4). Average Cu concentrations of root soil in the plants 
were estimated to be 12.4 ug/gm in Rhizophora and 13.82 ug/g in 
Avicennia. 
In both plant parts and sediments, iron (Fe) concentration was 
very high in comparison with the other two metals (Figure 5). 
Highest Fe concentration was recorded in station 1 in Rhizophora 
and in station 2 Avicennia sediments. They were 32500 ug/g and 
31512 ug/g respectively. Among the plant parts, Rhizophora root 
and bud had high Fe concentration. Average root concentration 
was recorded as 5086.6 ug/g and bud concentration 14160 ug/g. 
DISCUSSION 
In case of zinc, concentration was more in root soil. This might 
be due to the plant's structure as they have well-developed stilt 
roots, which have more metal accumulating capacity (Fiala and 
Hernandez,1993). Clark et.al. (1997) suggested that the soil 
contains more amount of biological sulphates that might produce 
a geological trap for heavy metals. In plant parts, zinc 
concentration was higher in bud and seeds and the stem was 
having minimum concentration. 
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