Influence of Spacing on Growth of Dhundul (Xylocarpus Granatum) in the Sundarbans of Bangladesh

International Journal of Research and Innovations in Earth Science Volume 7, Issue 6, ISSN (Online): 2394-1375 Influence of Spacing on Growth of Dhundul (Xylocarpus granatum) in the Sundarbans of Bangladesh

Dr. ASM Helal Siddiqui 1*, Sk. Md. Mehedi Hasan 2 and Dr. Md. Masudur Rahman 3 1 Divisional Officer, Mangrove Silviculrure Division, Bangladesh Forest Research Institute, Muzgunni, Khulna, Bangladesh. 2 Field Investigator, Mangrove Silviculrure Division, Bangladesh Forest Research Institute, Muzgunni, Khulna, Bangladesh. 3 Director, Mangrove Silviculrure Division, Bangladesh Forest Research Institute, Muzgunni, Khulna, Bangladesh.

Date of publication (dd/mm/yyyy): 28/12/2020 Abstract – Dhundul is one of the most important moderate-sized evergreen threatened mangrove species and play a pivotal role for the conservation of the ecosystem of Sundarbans. Between 2012 and 2017, an experimental plantation with randomize complete block design (RCBD) was conducted to enrich mangrove ecosystems by conserving dhundul at Moderate saline zone-comp nos. 31 of the Sundarbans. The objectives of this study are not only sustainable conservation of dhundul but also to create a better habitat as a source of the plus tree near future. Seedling survival percentage, mean height (h) and Mean Annual Increment (MAI) were observed each year to evaluate the effectiveness of dhundul plantation. The mean height (m), MAI (m) and survival percentage of dhundul differ significantly at different spacing. The highest mean height (m) and survival percentage have been found 2.46 ± 0.19, and 85%, respectively in the spacing 1m x 1m, as well as the highest Mean Annual Increment (MAI) for height 0.364m, were found in the same spacing. The result was highly significant (F = 1.57) at the 5% level for height. There are significant differences in the total mean height (m) among the spacing 2m x 2m, 1.5m x 1.5m and 1m x 1m. On the other hand (CV) at different spacing was 24.25, 20.09 and 21.98 for height. All these findings reflect that the growth performance of dhundul was better in 1m x 1m spacing. Artificial regeneration of dhundul was able to improve degraded residences and to ensure the sustainability of mangroves. So, it is highly recommended to establish long- term scientific research programs by setting up natural reserves of that threatened species and protect the existing mangrove mangrove ecosystem sustainably.

Keywords – Biodiversity, Dhundul (Xylocarpus granatum), Mangrove, Spacing, Species, Threatened.

I. INTRODUCTION

The Sundarbans, the largest contiguous mangrove forest in the world [1, 2] is considered as a site of national and international importance for the conservation of biodiversity [3, 4]. The Sundarbans covers an area of approximately 10,000 km2 and lies in the territory of Bangladesh and India [1]. The Sundarbans of Bangladesh lies between the latitude 21030 and 22030 N and between the longitudes 89000' and 89055 E [5]. This forest has enormous ecological and economic importance at local, national and global scales [3]. The Sundarbans plays an important role in the economy of the southwestern region of Bangladesh as well as in the national economy [6]. Most notable services of Sundarbans are acts as barriers against winds and storm surges [7], serves as coastal defense and reduces coastal flooding and coastal erosion provide livelihoods of coastal people as well as contributing to the local and national economy [8] The Sundarbans is a natural mangrove forest consisting of 245 genera and 334 species of trees, herbs, shrubs, bryophytes, and pteridophytes [9, 10] listed 66 plant species from the Sundarbans. Sundarbans also provides natural protection to life and properties of the coastal population in the cyclone prone Bangladesh [6]. Mangroves are uniquely adapted coastal plants of great ecological and

Copyright © 2020 IJRIES, All right reserved 76 International Journal of Research and Innovations in Earth Science Volume 7, Issue 6, ISSN (Online): 2394-1375 economic significance, but their habitat continued to disappear globally at a rate of 0.66% per year during the 2000–2005 periods [11]. This habitat loss has put at least 40% of the animal species that are restricted to mangrove habitat at an elevated risk of extinction under the International Union for Conservation of Nature (IUCN) categories and criteria [12]. The results published in PLoS ONE reveal that 11 of the 70 mangrove species in the world (16%) are at an elevated threat of extinction [13]. Economically, Mangroves are considered as a supplier of natural products such as charcoal, wild honey, timber, food and medicinal element [14]. Nearly 50% of the biome has been lost since the 1950s because of inadequate habitat protection, and large-scale habitat alteration. If the current rate of mangrove loss continues, the whole mangrove biome will disappear in the next 100 years [15]. There are only 70 mangrove species worldwide, compared to between 40,000 and 53,000 tropical forest tree species [16]. Already 16% of mangrove species are critically endangered, endangered or vulnerable and 10% are near-threatened [13]. More than 40% of the mangrove-endemic vertebrates are now also at risk of extinction due to habitat loss [12]. It was designated a Ramsar site under the Ramsar Convention in 1992 [17]. UNESCO declared the Sundarbans a World Heritage Site in 1997, because of its ‘Outstanding Universal Value’, biological diversity and the ecosystem services the area provides [17].

Dhundul is one of the most important mangrove species out of 66 species. Xylocarpus granatum J. Konig (Meliaceae), locally known as ‘Dhundul’ in Bangladesh is a moderate-sized evergreen tree with their gray bark [18]. The plant is well distributed among some continents like Australia, South-East Asia, and East Africa [19, 20]. Dhundul has been used traditionally to treat diarrhea, cholera and fever, as an astringent and emollient [21, 22]. The barks of this plant are used for tanning and in the preparation of an amber dye. The aqueous extracts of different parts of this plant are also reported to have significant antifilarial activity [23, 24]. The wood of Xylocarpus granatum is hard and durable and can be used for house building, boat-building, construction works and furniture making, however, the trees are twisted and often hollow so large pieces of timber may not be available. The wood is also used for handles and other small items and it can be used as fuel wood but burns quickly [25]. Dhundul is under threat from coastal development and harvesting, and another threat is global warming and the consequent rise in sea levels. The dried fruit peel is used as an appetizer [26]. The astringent bark has some medicinal uses. It is reported to cure dysentery, diarrhea and other abdominal troubles, and is also used as a febrifuge [25]. Bark is used for strengthening rope that needs to be used in the water [25]. The wood is very hard, moderately heavy, strong and durable, it is rarely, if ever, attacked by beetles, but is not resistant to termites [25]. The wood shrinks little and is usually easy to work and finish; it takes a high polish [27]. It is used for making small objects such as pins, tool handles etc, and house posts [28].

It is threatened by the loss of mangrove habitat throughout its range primarily due to extraction and coastal development and there has been an estimated 21% decline in mangrove area within this species range since 1980 [29]. As a result, the dhundul species is not found everywhere in the Sundarbans. Only found in very small quantities at Katka (compt. no. 06), Andarmanik (compt. no. 37, 41) and Alki (compt. no. 38) areas of the Sundarbans. If tree trafficking continues like this, the dhundul trees will be abolished from the Sundarbans within very short period of time. Mangrove Silviculture Division of Bangladesh Forest Research Institute, Khulna is trying to conserve this species. At present, experimental plantation is ongoing of moderate saline zone at Dhangmari (compt. no. 31) areas of the Sundarbans for the conservation of dhundul species. So, the objectives of this study are to not only sustainable conservation of dhundul species but also to create a better habitat as a source of the plus tree near future through identifying better spacing pattern which affects growth of

Copyright © 2020 IJRIES, All right reserved 77 International Journal of Research and Innovations in Earth Science Volume 7, Issue 6, ISSN (Online): 2394-1375 this species. Thus it is very important to conserve for the development of sustainable biodiversity and management of ecosystem in the Sundarbans mangrove forest of Bangladesh.

Fig. 1. Nursery and plantation area of dhundul in the moderate saline zone of the Sundarbans of Bangladesh.

II. MATERIALS AND METHODS

Site Characteristics and Ecological Zonation of the Sundarbans:

Climatic conditions of the Sundarbans is humid with annual rainfall of about 200-2100 mm. Highest temperature in the Sundarbans occur in April and May up to 400c and lowest temperature is 120c in December and January. The mean annual rainfall is about 1700 mm in most of the Sundarbans area. Maximum and minimum average relative humidity (RH) in the Sundarbans is 100% and 23% respectively. The soils of the Sundarbans are alluvial in nature, no distinct profile and hydromorphic with varying degree of gluing in the sub- soil horizon [30]. In general soil fertility decreases from east to west and from north to south [31]. The soil of the Sundarbans is slightly saline, silty clay loam and sub-soil consists of alternate layers of clay and sand, and it is uniform throughout the forests. The mean organic matter content in the top soil is 0.62% and pH range is 5.0- 8.0 throughout the Sundarbans.

Seed Collection, Nursery Raising and Maintenance of Nursery:

The experiment was conducted during the year of 2012 to 2017 to enrich mangrove ecosystems through the establishment and conservation of dhundul. Mature seeds of dhundul were collected from healthy mother trees at Katka khal (Compt. no. 06), Alki (compt. no. 38), and Andharmanik khal (compt. no. 37, 41) in the Sundarbans of Bangladesh (Fig. 1). The seeds were stored for seven days and subsequently the seeds were detached from the fruit by gentle pressure. The nursery was fenced to prevent animals from entrance. To raise seedlings of dhundul species in the nursery, bored polybags of 23cm x15cm size were filled with silt clay soil. Shade over the seedlings was given initially. At a subsequent time the shade was removed to allow the seedlings

Copyright © 2020 IJRIES, All right reserved 78 International Journal of Research and Innovations in Earth Science Volume 7, Issue 6, ISSN (Online): 2394-1375 for hardening. The seedlings in the nursery were maintained for about 10-12 months. Regular watering and weeding in the nursery were made. Nursery data on the growth performance of the species were collected. To raise seedlings of dhundul, mangrove nurseries were established in the moderate saline zone of Sundarbans in Bangladesh. Soli salinity varies from 0.50-16.00 (mmhos/cm) which is shown in fig. 2. All the nursery techniques and management systems were done according to [18].

Experimental Design and Plantation:

Experimental plantation of dhundul was conducted in moderate salinity zone of the Sundarbans under Compartment Nos. 31. The experimental site was prepared by weeding. The plantations were raised in Randomized Complete Block Design (RCBD) with three replications at 1m x 1m, 1.5m x 1.5m, and 2.0m x 2.0m spacing in a moderate saline zone (Fig. 4, 5, 6 and 7). The Sundarbans soil is humus enriched, alkali metal contents and distribution of minerals is heterogeneous [32, 33]. Mineral status of soil in general in relation to growth and development of plants particular is scanty. Sodium content of the soil varies from 5.7  0.73 to 29.8  2.1meq/100gm and organic matter content varies 4 to 10% in dry soil [34] and chloride varies 5.7 to 23.2meq/100gm. The number of seedlings were planted in each plot was 81(9 x 9). Thus a total of 729 (81 x 3 x 3) seedlings were planted in a moderate saline zone (Fig. 4, 5, 6 and 7). Experimental plantations were initially protected by fencing. Planting was carried out in June with the onset of monsoon. The average height of the seedlings was 80cm at the time of planting. Weeding was done three times in the first year after planting and twice in subsequent years. The survival and early growth of the seedlings were observed on the effect of spacing. Planting was carried out over an area of 0.3 ha.

Data Collection and Analysis:

Growth and survivability data of planted dhundul were recorded twice in a year from Sundarbans by mangrove silviculture division, Bangladesh Forest Research Institute. Data on water salinity, soil pH, sedimentation, and inundation were also recorded (Fig. 3). The collected data were processed, tabulated and then charts, graphs, tables were prepared by using MS excel. ANOVA and coefficient of variation were analyzed to observe if there were any differences between spacing.

III. RESULTS AND DISCUSSIONS

Hasan et al [35] have classified soils having <2.0 mmhos of electrical conductivity as less saline, 2.0-4.0 mmhos of electrical conductivity as moderate saline zone and > 4.0 mmhos of electrical conductivity as strong saline zone. There are three ecological zones in the Sundarbans such as less saline water zone (LSWZ), moderate saline water zone (MSWZ) and strong saline water zone (SSWZ). The floristic composition of the Sundarbans is defined by the distributions of three species, H. fomes, E. agallocha and C. decandra. All three occur throughout the Sundarbans but in different proportions depending on salinity Karim [36] classifies salinity boundaries based on pre-monsoon and post-monsoon levels of the river water. These are oligohaline (0-5 ppt), mesohaline (5-18 ppt) and polyhaline (> 18 ppt). Soil salinity (mmhos/cm) from January to December in 2011 of the nursery area at Dhangmari (Moderate saline zone) of the Sundarbans was 8.00 mmhos/cm, 14.00 mmhos/cm, 16.00 mmhos/ cm, 12.00 mmhos/cm, 0.50 mmhos/cm, 0.65 mmhos/cm, 0.70 mmhos/cm, 0.70 mmhos/cm, 0.80 mmhos/cm, 0.84 mmhos/cm, 0.70 mmhos/cm and 6.50 mmhos/cm consecutively (Fig. 2).

Fig. 2. Soil salinity (mmhos/cm) information in 2011 of in the Fig. 3. Six years of Information on water salinity (ppt) and soil pH of nursery area at Dhangmari (Moderate saline zone) of the dhundul plantation in moderate saline zone of the Sundarbans. Sundarbans.

Water salinity (ppt) of April month in 2012, 2013, 2014, 2015, 2016 and 2017 are 13 ppt, 15 ppt, 5 ppt, 16 ppt and 15 ppt. Soil pH of April month in 2012, 2013, 2014, 2015, 2016 and 2017 are 6, 6, 5, 7, 7 and 5. Water salinity (ppt) of April month in 2012, 2013, 2014, 2015, 2016 and 2017 are 0 ppt, 0 ppt, 6 ppt, 1 ppt and 5 ppt. Soil pH of October month in 2012, 2013, 2014, 2015, 2016 and 2017 are 7, 6, 7, 5, 6 and 4 (Fig. 3).

Mangrove nursery was set up in a moderate saline zone of the Sundarbans mangrove forest of Bangladesh for this research work. The growth of dhundul seedlings at the mangrove nursery in the Sundarbans were shown in fig. 4.

Fig. 4. One year-old seedlings of dhundul at mangrove nursery Fig. 5. Monitoring the growth performance of experimental plantations in the moderate saline zone of the Sundarbans. of dhundul at 1m x 1m spacing in moderate saline zone.

Fig. 6. Growth performance of experimental plantations of Fig. 7. Growth performance of experimental plantations of dhundul at dhundul at 1.5m x 1.5m spacing in moderate saline zone. 2m x 2m spacing in moderate saline zone.

Dhundul was planted on July 2012 in the moderate saline zone of the Sundarbans. Five years old experimental plantations of dhundul species at 1m x 1m, 1.5m x 1.5m and 2m x 2m are shown in figure-5, 6 and 7 respectively. Measuring the performance of dhundul plantations depend mainly on the objectives of the planting application, and observing factors were chosen accordingly. Assessments were done annually by monitoring the survival rate and one or more structural characteristics of the stand, including mean height (h) and Mean Annual Increment (MAI). The young seedlings need regular watering (daily in the summer and 3-4 times a week in the other season). Plants need to be cleaned regularly to ensure weeds as well as protection from pests and harmful animals. Proper shading was applied at different times of the year depending on the age of the seedlings. Seedlings should be given partial shade for the first 2-3 months before moving to full sunny areas. Planting seedlings in polybag is economical and easy to transport the seedlings. The survival rate of seedlings in nurseries can be increased up to a hundred percent before planting the seedlings of dhundul. This allows the seedlings to develop a healthy root system before planting. The average germination percentage of dhundul was eighty and height after one year was 80cm (Shown in table-1).

Table 1. Phenological observations and germination performance of planted dhundul in the Sundarbans of Bangladesh.

Sl. No. Parameter Moderate Saline Zone of the Sundarbans

1. Fruit collecting time April-May

2. Number of average seeds per fruit 8-16

3. Number of average seeds/kg 7-21

4. Seed storage time (days) 7

5. Number of seeds sown 3000

6. Initiation of germination (days) 7

7. Completion of germination (days) 115

8. Germination percentage (%) 90%

9. Average height after one year (cm.) 80

Dhundul species were selected for the experiment in the moderately saline zone of the Sundarbans. It grows well in the river banks and chanals of the moderate saline areas. This species occurs with gewa (Excoecaria agallocha), kankra (Bruguiera sexangula), lal kankra (Bruguiera gymnorrhiza), jhana (Rhizophora mucronata) and goran (Ceriops decandra) in the Sundarbans of Bangladesh. Detail site descriptions of experimental plots for dhundul are given in table-2.

Table 2. Details site description of experimental plots for dhundul in the Sundarbans.

Sl. No. Parameter Moderate Saline Zone in the Sundarbans of Bangladesh

1. GPS of the site Latitude: 220 26′ 53′′, Longitude: 890 35′ 55′′

2. Plantation year 2012

3. Area of plantation (ha) 0.3

4. Spacing 2.0m x 2.0m,1.5m x 1.5m, &1.0m x 1.0m

5. Soil texture Silty-clay

Sl. No. Parameter Moderate Saline Zone in the Sundarbans of Bangladesh

6. Soil pH 5.90

7. Water salinity ppt. (part per thousand) 13.00

8. Inundation condition Inundation by all tides in monsoon (Regular)

Gewa (Excoecaria agallocha), kankra (Bruguiera sexangula), 9. Initial vegetation lal kankra (Bruguiera gymnorrhiza), jhana (Rhizophora mucronata) and goran (Ceriops decandra)

Experimental orchards of dhundul were raised with polybags seedlings and their success rate was assessed regularly and growth rate was maintained. Growth and survival data were recorded twice in a year. It is important to identify the cause of death and take curative action. Dhundul has an adaptive capacity that can tolerate moderate saline conditions. Salinity is the main part of reducing contests into mangrove species and other plants. The genus dhundul needs fresh-water need for germination, early growth and survival of the genus dhundul. Restoration planners need to take into consideration of the dominant mangrove species in the restoration site and determine the optimum salinity levels or thresholds for those plants [37, 38]. Total mean height and standard error are shown in figure-8, Mean Annual Increment (MAI) is shown in figure-9, survival percentage is shown in figure-10, Coefficient of Variation (CV) is shown in fig. 11 and F-value of dhundul trees as a view of growth performances of five years old plantations under moderate saline zone in the Sundarbans is shown in table-3.

Fig. 8. Effect of spacing on the growth of dhundul with standard Fig. 9. Mean Annual Increment (MAI) of 5 years old of dhundul error in the moderate saline zone of the Sundarbans. plantation in the Sundarbans.

Fig. 10. Effect of spacing on survival percentage of dhundul in Fig. 11. Coefficient of Variation (CV) of different spacing for the moderate saline zone in the Sundarbans. dhundul species in the moderate saline zone of the Sundarbans.

MAI (m) and survival percentage of dhundul (shown in fig. 8) trees differ significantly at different spacing. The highest mean height (m), standard error, and survival percentage have been found 2.46, ± 0.19, and 85% respectively in the spacing 1m x 1m as well as the highest Mean Annual Increment (MAI) for height 0.364 m were found in the same spacing. The most suitable spacing was recorded for dhundul species was 1.0m x 1.0m in moderate saline zone of the Sundarbans. Height data analysis of variance (ANOVA) and the Coefficient of Variation (CV) have been done. The computed F = 1.57** which was highly significant at the 5% level (were shown in table-3). There were significant differences in the mean height (m) with standard error (2.64 ± 0.19, 2.36 ± 0.15, 2.27 ± 0.16) and survival percentage (85, 85, and 83) among the spacing of 1m x 1m, 1.5m x 1.5m and 2m x 2m. On the other hand Coefficient of Variation (CV) at different spacing was found 24.25, 20.09 and 21.98 for height. All these findings reflect the growth performance of dhundul species was better on 1m x 1m spacing compared to 1.5m x 1.5m and 2m x 2m spacing.

Table 3. Height data analysis of variance (ANOVA) of five years old dhundul species planted in moderate saline zone at different spacing in the Sundarbans of Bangladesh.

Analysis of variance (ANOVA)

Source of Variation SS df MS F P-value F crit

Between Groups 0.19 2 0.10 1.57 0.23 3.35

Within Groups 1.64 27 0.06

Total 1.83 29

Three of 10 (30%) of mangrove species found primarily in the downstream estuarine and low intertidal region are in threatened or Near Threatened categories. In these mangrove areas, populations are experiencing severe declines due to coastal development and the conversion of tidal wetlands to fish ponds or other land uses [39]. Different techniques were used for planting dhundul species. The first technique was to transplant seedlings from a mangrove forest floor to the plantation site. The second strategy was to collect ripe seeds from the Sundarbans and plant them directly in the planting area. The third strategy was to lift the desired seedlings to the nursery and then transplant them to the planting place. In this study, the third strategy was followed in the experimental planting activity of dhundul. This experiment was conducted to disclose the growth of dhundul species in the moderately saline zone of the Sundarbans in Bangladesh. Artificial regenerations of dhundul species can improve degraded habitats to facilitate decolonization by native mangrove species. Existing mangrove lands need to be protected and managed as an ecosystem by adopting long-term scientific programs to establish and restore natural reserves to ensure the sustainability of mangrove species in the Sundarbans. Bangladesh has signed and ratified the World Heritage Convention, Ramsar Convention and the Convention on Biological Diversity and the government of Bangladesh has recently developed the Biodiversity National Assessment and Program of Action 2020 to implement sufficient measures to halt further degradation of biological resources. To maintain continuity of mangrove ecosystem enhancement of survivality and growth performance is important compare to natural regeneration and threatened mangrove species. The entire study leads us to conclude that survival rate and growth status of mangroves can serve as potential indicator of ambient. Despite this it is necessary to collate comprehensive specific information of species for mangroves in Bangladesh. It is a matter of urgency to protect and propagate this threatened mangrove species to increase the

Copyright © 2020 IJRIES, All right reserved 83 International Journal of Research and Innovations in Earth Science Volume 7, Issue 6, ISSN (Online): 2394-1375 population size in their habitats and maintenance of their ecosystem. Research intervention is required to overcome the problem of low seeds viability and availability of seeds of this species.

IV. CONCLUSION

Planting dhundul orchards can go a long way by enriching a healthy mangrove forest, protecting the ecosystem, maintaining soil stability, enhancing future natural regeneration, isolating and conserving large amounts of carbon. Despite their economic and environmental importance, these forests are largely under threat due to human activities. This requires the protection and development of ecosystems. One of the most effective ways to protect the Sundarbans is to conserve a species in the right place for forest conservation and development. Successful environmental assessment is required for the conservation of the dhundul species. Mangrove tree planting method can be followed for the expansion of plant species on a large scale. The exact 1m x 1m spacing was determined for the dhundul species. The slightest difference in nursery and plantation techniques of different mangrove species can be noticed. Nursery and 1m x 1m planting techniques for dhundul species were determined. The purpose of increasing the planting of dhundul is to prevent soil erosion, increase natural regeneration in the future, to produce improved sources of planting materials, to produce mother trees, to create seed production fields as well as to establish seed orchards, carbon sequestration, and restoration of endangered species and beautification of the Sundarbans. It will also help to improve the field of apiculture as well as enrich the mangrove ecosystems and biodiversity development.

ACKNOWLEDGEMENTS

This research work is dedicated to all the members of the Mangrove Silviculture Division, Bangladesh Forest Research Institute and thanks to all those who have sincerely collaborated to complete this research work during the study period.

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First Author Dr. Asm Helal Siddqui was born in Kaliganj, Jhenaidah, Bangladesh in the year 1964 in a respectable Muslim Family. After obtaining B.Sc. (Hons.) and M.Sc. Degree in Botany Department from Rajshahi University in 1986 and 1987 respectively. He was appointed as a Research Officer at Mangrove Silviculture Division under the Bangladesh Forest Research Institute on the 16th November, 1993 and working till date. He did his Doctoral degree (Ph.D.) in plant Pathology 1n 1914. He also presented many papers in the National Seminars during his present job. He has so far number of publication (80+) at his credit in the field of forestry on wildlife and silvicultural aspect published in the National and I- -nternational journals. At present he is working as a Divisional Officer (DO) in Mangrove Silviculturte Division of Bangladesh Forest Research Institute of the People’s Republic of Bangladesh.

Second Author Sk. Md. Mehedi Hasan was born at Kayra under Kayra upazilla in Khulna district on June 24 in 1974 in a respected Muslim family. His father name is Sk. Abdul Bari and mother’s name is Magfura Begum. He graduated from the National University of Bangladesh in 1994. He was appointed as a Research Assistant under the Bangladesh Forest Research Institute on the 1st January, 2005. He joined as Field Investigator at Mangrove Silviculture Division in 10th March 2009 under the Bangladesh Forest Research Institute and working till date. Initially he worked as a Research Assistant from 1st January 2005 to 09th March 2009. He promoted from 2011 as a Field Investigator of Mangrove Silviculture Division (MS -D) of Bangladesh Forest Research Institute (BFRI), Khulna, Bangladesh.

Third Author Dr. M. Masudur Rahman was born at Banaripara under Banaripara upazilla in Barisal district on October 12 in 1962 in a respected Muslim family. His father name was late Moulana Yunus Ali Akanda. He passed his S.S.C. examination from Banaripara Union Institute, Barisal and H.Sc From Sher-e-Bangla Fazlul Haque College, Jhalokathi, Barisal in 1980 and placed 11th position in combined merit list from science group. He graduated from Kuban Agriculture State University, USSR in 1987 and achieved 1st class. He passed PhD from the same university in 1990. He joined as senior research officer in Mangrove Silviculture Division in 10th November 1993 in the Bangladesh Forest Research Institute. He promot- -ed from 1st May 2007 as Divisional Officer. He worked Chief Research Officer and presently he is working as the Director of the BFRI, Chittagong, Bangladesh. His number of Publication is more than 30.