The impact of ecological factors on plant diversity in ben en national park

ACKNOWLEDGMENT

First and foremost, in order to complete the training program and to assess student’s
the results of learning as well as making the condition for student in investigation and
scientific research, I have conducted the thesis under the permission of the Vietnam Forestry
University, the Faculty of Forest and Environment Management with thesis’ name: The impact of
selected ecological factors on plant diversity in Ben En National Park in Thanh Hoa Province.
In particular, I would like extend my grateful thanks to both my supervisor, including:
Assoc. Prof. Dr. Hoang Van Sam and Dr. Tobias. They have supported me throughout the
research process as well as during the period of completing the thesis. Besides, I would also
like to thank Dr. Lee Macdonald who comes from professor Colorado State University in
judging and fixing the controversial issue in my thesis. Last but not least, I sincerely thank for
the board of directors and staff in Ben En National Park helped me to deal with this topic.
Eventually, this is initially familiar with scientific research and as the results of poor
experiments which lead to get the unavoidable errors. I look forward to receiving suggestion
from teachers and friends.

1


ABSTRACT

The thesis have provide the fundamental information in the plant species diversity and
vegetation types as well as some factors influencing on the plant diversity in Ben En National
Park. The thesis recorded about 363 vascular plant species belonging to 70 different families.
Besides, there are two main types of vegetation which witnessed in National Park, including
moist tropical evergreen and secondary lowland limestone forests, moist tropical evergreen
lowland forests and secondary forest after mining on other soils with heavily and slightly
disturbed subtypes illustrating the impact of human activities on. In terms of the first
vegetation type, it consist of some subtypes which are slightly disturbed, heavily disturbed
and shrub-land on lime stone, while the second main one is tropical evergreen lowland forest

on other soils with slightly disturbed forest on ferralitic or alluvial soil, heavily disturbed
forest on ferralitic soil and shrub-land on ferralitic soil. Moreover, there are plenty of high
conservation species living in Ben En National Park, among which I have found and
recognized a number of 7 species are listed in the Red list of IUCN (2015) and 9 species
belong to the Red data Book of Vietnam (Ban 2007) as well as many plant species are in the
face of extinction. Last by not least, the overview of the impact of ecological factors on the
plant diversity in the distribution and the development showed up in this thesis with some
such dominant ecological factors as: the canopy cover, shrub and herb cover and the
elevation.

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TABLE OF CONTENTS

ACKNOWLEDGMENT
ABSTRACT
TABLE OF CONTENTS
LIST OF TABLE
INTRODUCTION ...................................................................................................................... 1
CHAPTER I. LITERATURE REVIEW .................................................................................... 3
CHAPTER II. OBJECTIVES, SCOPES OF THE STUDY AND METHODOLOGY ............. 7
2.1. Objective.............................................................................................................................. 7
2.2. Subjects and scope of research ............................................................................................ 7
2.3. Content ................................................................................................................................ 7
2.4. Methodology........................................................................................................................ 7
2.4.1. Material inherited and preparation method. ..................................................................... 7
2.4.2. Field investigation method. .............................................................................................. 8
2.4.3. Non-field investigation method. ..................................................................................... 11
CHAPTER III. RESERCH AREAS ......................................................................................... 14

3.1. Geographical Location ...................................................................................................... 14
3.2. Topography........................................................................................................................ 14
3.3. Climate and Hydrology ..................................................................................................... 16
3.4.Forest resource.................................................................................................................... 16
3.5.Characteristics of social economy. ..................................................................................... 17
CHAPTER IV. RESULTS AND DISCUSSION ..................................................................... 18
4.1. Vegetation types in Ben En National Park and its characteristics ..................................... 18
4.1.1. Moist Tropical evergreen in lowland limestone forests ................................................. 18

3


4.1.2. Moist tropical evergreen lowland forests ....................................................................... 20
4.1.3 Plantation forest ............................................................................................................... 23
4.1.4 Agricultural land .............................................................................................................. 24
4.2. Conservation of plant species status in Ben En National Park .......................................... 24
4.3. The impact of some ecological factors on plant diversity in Ben En National Park ......... 24
4.3.1. Impact of elevation factor on plant diversity in Ben En National Park .......................... 24
4.3.2. Effect of the canopy cover to plant diversity.................................................................. 29
4.3.3. Effect of shrub and herb cover to plant diversity ........................................................... 30
CONCLUSION ........................................................................................................................ 32
REFERENCE

4


LIST OF TABLE

Table 4.1. Fluctuation number of plant species and families by evelation in Ben En National
Park ........................................................................................................................................... 25

Table 4.2. The relationship between elevation and the index .................................................. 28
Table 4.3. Familiar level in species composition in vegetation structure among different
altitude ...................................................................................................................................... 28
Table 4.4. The impact of canopy cover on regeneration density. ............................................. 29
Table 4.5. the result of surveying shrub and herb layer. .......................................................... 30
Table 4.6. the impact of shrub and herbs cover on regeneration species ................................. 31

5


INTRODUCTION
It is universally acknowledged that tropical rainforests are terrestrial ecosystem on
Earth illustrating the abundance of species diversity, but nowadays, we are witnessing about
the disappearance of species at a dizzying pace because lands are renovated by timber,
agriculture, and other uses (Fimbel et al. 2001; Meijaard et al. 2005). Vietnam’s forests are
extremely biodiverse (Thin 1997) and Vietnam is one of the nations ranked the 16 th in global
bio-diverse (WCMC 1992). The abundance of plant diversity is one of the most
characteristics in tropical rainforests, which cover less than 10% of the total land areas; there
are more than 50 percent of earth’s plant species found in tropical rainforests (Wilson 1988;
Mayaux et al. 2005). Unfortunately, the majority of Vietnam’s forests have significantly
decreased during the last 60 years (Chien 2006). Around 6 million ha of tropical forests have
been lost (Achard et al. 2002). As a result, the forest cover witnessed a downward trend in
1985 and 1995 at 30 percent and 28 percent, respectively (Lung 2001; Hoang et al. 2008 a). In
1998, the Vietnamese government deployed the 5 million ha Reforestation Program with the
aim of planning 5 million ha of forests in 2010 as well as restoring the cover of forest to reach
of 43 percent (Lung 2001).
Plants are the world’s biodiversity as well as demonstrating its essential resource on
the earth (GSPC 2012). There are many thousands of wild plants used with the aim of
economic and providing food, medicine, fuel shelter for humans around the world in over
period of time. The United Nations Convention on Biological Diversity noted that:

“Biological resources probably contribute into world’s economy and the poor’s demands at
about 40 percent and 80 percent, respectively (Convention 2011). Also, the more life’s
diversity, the more popular opportunity for medical discoveries, economic development and
facing to such new challenges as: climate change. Unfortunately, many plant species are
threatened by habitat transformation, over-exploitation, pollution and climate change.

1


Ben En National Park is known as the ecological complex of mountain, river, lake
with more than 16.000ha of area and the plentiful plants and animals system. It is homeland
of the famous green ironwood in Vietnam. According to researching of scientists, Flora in this
park includes 58 species were listed in IUCN Red Book, 46 species belongs to Viet Nam Red
Book in 2007. The Red List species in Ben En National Park were identified based on the Red
Data Book of Vietnam (IUCN 2006, Ban 2007) and their conservation status was assessed
using the frequent appearance of species including trees and stump which is found during the
field inventory (Hoang et al. 2008a, b, c). Obviously, there are the plenty of research which
related to the case of plant diversity in Vietnam.Although, there are several studies on the
environmental

characteristics,

natural

distribution

of

some

such

species

as

Erythrophloeumfordii, Melienthasuavis Pierre or Garciniafagraeoides, there is less research
on the effect of ecological factors (topography, soil physical characteristics and human) to the
distribution and the development of plants in Ben En National Park. In recent decades,
research on plants diversity has become more and more important. Protected areas contribute
to the protection as well as conservation of the biodiversity and provide diverse public goals
like socio-economic development. With the aim to study the impact of ecological factors on
biodiversity of flora species in the study area, so I conducted this thesis: “The impact of
ecological factors on plant diversity in Ben En National Park”.

2


CHAPTER I. LITERATURE REVIEW
Environmental factor or ecological factor or eco-factor is any factor, including abiotic
or biotic influencing living organisms (Gilpin, A. 1996). Abiotic factors are the non-living
components of the ecosystem which play a critical role in biology of the ecosystem. There are
several abiotic factors which exert huge impact on plants, namely: topography, temperature,
light, moisture, soil nutrients, and the percentage of canopy cover. Normally, abiotic factors
definitely influence on the distribution of plant diversity and its abundance (Hotra et. al 2003).
Besides, there are plenty of studies illustrated that abiotic environment factors, such as
topographic parameters can cause changes of plant diversity (Bennie et al., 2006; Marini
Lorenzo et al., 2007). Grassland diversity is heavily affected by environment factors; e.g. soil
and topography (Cristofoli, 2010; Marini Lorenzo et al., 2007). At least, since the 1890s, it is
obvious that the local vegetation situation affected by the topography through the subject

interactions which is recognized (Warming 1895). In terms of temperature, the vast majority
of seedlings distribute to the forest with dark closed canopy condition, leading to the
necessary of examining the impact of temperature on seedlings growth not only in bright
conditions but also in dark conditions (Koi Takahashi et al. 2011). Besides, according to (Yin
et al. 2008) reported that seeds growth of Betula albo-sinensis rose in the warm condition with
0.510C higher than the ambient air condition.
On the other hand, the biotic factors are living organisms including competing species,
parasites, predators and humans or in other word macro- and micro- organisms (Muoghalu JI.
2003). Moreover, they will affect plant growth and development through different ways.
Specially, the morphology of plants is one of the genetic factor influenced by those organisms
(Ben G. Bareja, 2011). Certainly, human not only exerts positive and negative impact on the
environment, humans but also have transformed 40–50% of the ice-free land surface,
changing prairies, forests and wetlands into agricultural and urban systems (F. Stuart Chapin
et al. 2000).
3


Plants are influenced by human activities which can change the interaction among
species in the community (Huston 1994; Acharya 1999). Habitat loss, fragmentation, and
degradation are currently the most important threats to biodiversity (Primack 1993). In
contrast, a coin has two side, so human activities also have different influences on
biodiversity (Putz et al. 2000). For instance, numerous studies have shown that although
logging can cause numerous damage to the forest ecosystem, logged-over forests would maintain
original biodiversity (Whitmore & Sayer 1992; Cannon et al. 1998; Meijaard et al. 2005).
Ecological factor plays a significant role for the ecological development as well as the
biological diversity of species in the whole ecosystem. Fortunately, humans in general
became increasingly concerned about the impact of environment on habitat. Viet Nam is not
only one of the countries with one of the highest biodiversity in the world with plentiful
source of natural ecosystem, but Viet Nam also contains many rare genes with a variety of
endemic species due to the complexity of the terrain, climate, creating suitable conditions for

various ecosystems. In addition, there is also evidence that environmental factors or
ecological factors such as soil nutrients, canopy openness, slope and herb cover affect the
distribution of tree species and forest composition (Duivenvoorden 1995, Potts et al. 2002).
Plant biodiversity in Vietnam
There is a variety of diverse flora in Vietnam with around 28% of its total endemic
species. (Thin 1997). Moreover, Vietnam is considered as one of the most biologically diverse
countries in the world and the percentage of precious and endemic species of fauna and flora
that probably are concentrated mostly in Vietnam. However, a few decades, there are the
plenty of species recognized as endemic species in Vietnam and it also appears in 3 countries
including China, Laos, or Thailand (Hoang et al. 2004). According to the statistics, Vietnam
has 11,373 plant species that belong to 2524 genera , 378 families and 7 major plant groups
(Table 2.1) (Thin 1997).

4


Besides, A few years later, according to some estimation illustrating the number of
flora in Vietnam reach to 12,000 species (Thin 2000). A number of preliminary estimates
offer figures of about 600 indigenous species of vascular plants in Vietnam (Tolmachev 1974;
Nguyen Nghia Thin 1997; Phan Ke Loc 1998). The total number of species belongs to
vascular plants known in Vietnam for the time being is about 10,350 species in 2,256 genera
and 305 families (Phan Ke Loc 1998). Certainly, the flora of Vietnam is extremely diverse
with ranging from general species to endemic species. The rate of endemic species has been
variously recorded, ranging from 20% (Pocs 1965) to as high as 50% (Thai Van Trung 2000).
It is universally acknowledged through a more conservative estimate that there are
approximately about 10% of species and 3% of genera well-known as Vietnam’s endemic (Vo
Quy 1995). Among 305 vascular plant families reported for Vietnam, the highest levels of
endemism occurs in the Acanthaceae, Anacardiaceae, Annonaceae, Apocynaceae, Araceae,
Arecaceeae, Asclepiadaceae, Celastraceae, Ericaceae, Euphorbiaceae, Fagaceae, Myrsinaceae,
Rubiaceae, Sapindaceae, Sapotaceae, Theaceae and Zingiberaceae (Schmid 1974; Takhtajan

1986; Rundel 1999). Recently, an inventory of the orchid species in Vietnam showed that the
uniqueness of the family is 20% (Averyanov&Averyanova 2003).
On the other hand, The Vietnamese government has established a system of protected
area with the aim of protecting the threatened biodiversity as well as conserving the main
ecosystems present in Vietnam and the vital landscapes for culture, ecology and biodiversity
(Tai 1995; Vn 2003; Chien 2006). Initially, the first National Park in Vietnam is Cuc Phuong
established in 1962 with the aim of forest production and conservation (Thu 2002 ).
Afterward, gradually, Vietnam’s the national park and nature reserve has developed in a
sudden way. In 2015, Vietnam had 164 regions of special purpose with different goals and its
total area of 2.2 million hectares which constitute 6.8 percent of the total area in Vietnam
(VNForest 2015)

5


Ben En Natural Park
In particular, one aim is to better understand the plant species diversity and recognized
the value of plants species. The thesis has chosen Ben En national park. Ben En National
Park, one of the 30 National Parks in Vietnam (Forest Protection Department 2006). Ben En
National Park is situated in NhuThanh and NhuXuan districts of the ThanhHoa province in
Vietnam 190 30’ to 19040’ N by 105021’ to 105035’ E. The park was established by the
decision amount 33 dated 27 January 1992 of the Chairman of the Council of Ministers of
Viet Nam, with the purpose of conservation of natural ecosystem, restoration of endanger
species, tourism development, settle down the buffer zone’s local people and at the same time,
mobilizing people join management protection and sustainable development. The majorities
of the people who are living in the National Park belong to the Kinh, Thai, Muong and Tay
ethnic groups; besides there are still a small number of Tho people. Furthermore, the
livelihood of local people still depend on forest resources, specially timbers and Non Timber
Forest Products (Hoang et al. 2008 b & c). Human exploitation exerts a huge impact on the
vegetation of Ben En National Park (Khoi 1996; Hoang et al. 2008 a). Unfortunately, since

1992, human activities such as illegal logging, trading and hunting have been continuously
exploiting until now (Tordoff et al. 2000; Hoang et al. 2008 a & c). The effects of former
logging activities were still evident in the plots established for this study and some of the
stumps counted as indicators of human disturbance probably dated back from before 1992.
Ben En National Park has 1389 vascular plant species belonging to 650 genera and 173
families (Hoang et al. 2008a).

6


CHAPTER II. OBJECTIVES, SCOPES OF THE STUDY AND METHODOLOGY
2.1. Objective
-Determining the vegetation types and high conservation value of plant Ben En
National Park.
-Determining how ecological factors impact on plant diversity in Ben En National Park.
2.2. Subjects and scope of research
Subjects: Plants species in Ben En National park
Scope: The thesis focus on determining the vegetation type’s characteristics and
conservation status of plants species as well as having an overview of some ecological factors
influencing on plant diversity in the Park.
2.3. Content
Assessment of the status of high conservation plant species value in Ben En National
The characteristic of vegetation types in limestone and in others soil.
Study the impact of some ecological factors on plant diversity in Ben En National Park.
2.4. Methodology
2.4.1. Material inherited and preparation method.
2.4.1.1. Looking for scientific research, report, student thesis proposal, books which related to
the flora in Ben En National Park.
-Find out ecosystem, habitat types, nature condition of the study area.
-Economic and living condition of local people who have affected directly to the

ecosystem.
-Evaluation of maps of Ben En National Park
-List of plants species in Ben En National Park.
-Document, report, scientific research, student thesis proposal which related to rare
flora in Ben En National Park: the number of species, genus, families….

7


2.4.1.2. Preparation
-Prepare tools: Compass, calipers, camera, GPS, tapes…
-Prepare document and maps relate to natural condition, social, economic in Ben En
National Park.
2.4.2. Field investigation method.
2.4.2.1. Transect line method.
Supporting for studying and assessing these objectives as well as determine the area of
the studied population and the amount of each individual in the population. We established 30
sample in Ben en National Park with the same size of 500m2 or 25 meters in length and 20
meters in width. The longer side of these plots has to be perpendicular with the slope of the
topography. In sample plots, determining the structure of the studied species and study some
physiological characteristics of the species.
Inside each plot, we set up 5 5x5m subplots, 4 at 4 corners of the plot and the
remaining one at the center of the plot. Investigate and measure individual species in selecting
areas to find out regeneration status of each species, characteristics of shrubs and herbs, and
some others. In each 30 plots, we just take trees with a dbh ≥ 5cm to identify and ignore the rest of
species. However, we also identify the trees with dbh <5cm and h ≥ 1m in each subplots.
Generally speaking, we established the sample plots at transect line associating with
distinctive region. In Dien Ngoc area, we started establishing the sample plots at the regions
namely Dong May, K1 – TK 636 and ending with Khe Ba Nui. in Song Chang region, we
began the sample plots at the regions including L1-K6-TK 619, Lan Chay region- K4- TK

619, road segments to Thung Sen and culminating in Thung Sen. Next, as for Xuan Bai
region, the sample plots are created ranging from Xuan Bai forest station to K1-TK 622- Eo
Ba Ky.. In terms of the places used to establish the sample plots in Xuan Binh station, this
transect line from Khe Ngon to K4-TK633 (patrol road) and ending in K8-TK 633( patrol

8


road). The last station used to survey is Xuan Thai station with the transect line ranging from
K2-Tk634a - Cổng trời to L15-K1-TK626-Khe Chuồn and to L16-K1-TK626 - Khe chuồn.
2.4.2.2. Field investigation.
a) Estimate the distribution and density of species at some selected areas.
b) Based on observation and some characteristics of studied areas to determine
what vegetation types in the study site are.
c) Investigate and estimate some influencing factors which could affect the
environment, ecosystem and habitat of species.
2.4.2.3. Data collection
2.4.2.3.1. Investigation of high individual species.

Investigate, collect specimen, calculating all of the individuals precious species found
in diameter at breast height (D1.3) greater than or equal to 5cm.
D1.3 measured by calipers glasses.
Measuring tree height (Hvn) and the high under branch (Hdc) by Blume-leiss measure
Measuring canopy diameter (Dt) by tape in two dimensions East-West and south.
For the tree difficult to measure (due to difficult terrain), using empirical observation
position from the tree was measured.
Table: Investigation of species in transect line
Transect line…
Forest type…..
Height… Steepness …. Slope direction

No.

Areas

Species

D1.3(cm)

Hvn(m)

1

9

Dt(m)

Height

Status

Note


2.4.2.3.2. Investigation of reproduction species.
Investigation of natural reproduction plant species along the transect line. Observe the
status of those species, specially the species near parent trees.
Table: Investigation of reproduction trees in transect line
Transect line...
Forest type...
Height… Steepness …. Slope direction

Days of investigation

surveyor
Source of

No.

Species

Height of trees ( cm )

Status
reproduction

<50

50-100

>100

Seeds

Buds

A

B

C

Note :
A : Good
B : Normal
C : Bad
2.4.2.3.3. Investigation of shrub and herb species.
There are several criteria of collecting the data associating with shrub and herb, such
as: dominant species, the average of height, the percentage of cover, the number of cluster.
Table: Investigation of shrub and herb species
Height… Steepness …. Slope direction
Days of investigation

surveyor

Location
No.

Species

N(cluster)

N(trees)

10

%(cover)

Note


2.4.3. Non-field investigation method.

2.4.3.1. Data processing and analysis.


Determine the density of reproduction trees : Density (N) is calculated using the formula:
N = (N / S) × 10000 (trees / ha)
We have :
N: the number of counted trees in the area of S (tree)
S: measurement area (m2)



Using a paired comparison method to assess results



Using an assessment of Vietnam's Red Book, 2007 (Part II-Plant), the evaluation

criteria of the IUCN (2015)


A diversity index is a mathematical measure of species diversity in a community. It

illustrates several information of community composition such as: the number of species
present, the percentage of individuals that belong to X species, so on. Moreover, a
quantitative measure that reflects how many different types in a dataset, and simultaneously
be likely to take into account how all the basic entities (such as individuals) to be distributed
among those types. There are the couple of diversity index but basically, three indexes below
are suitable for calculating and estimating the impact of ecological factors on plant diversity
in Ben En National Park.
Shannon index (H species’ biodiversity index)

The diversity trait is a statistical algorithm combining with 2 factors: the number of
species’ composition and the possibility of appearance of individual in species (Shannon and
Wiener, 1963, Alekseiev, 2007). H index does not only depend on the number of species but
also the number of individuals and the probability of occurrence of individuals in each
species. To specify, H is defined by the following formula below:
H= - ∑

=- ∑

( )

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Where:
 H: Shannon’s diversity index
 S: Total number of species in the community (richness)
 Ni: the number of i species
 N:The number of all trees
 Pi: The proportion of individuals belonging to the ith
species
Simpson index (Concentration of dominance)
The Simpson index was introduced in 1949 by Edward H. Simpson. Simpson’s
diversity index is a measure of diversity. In ecology, as for habitat, it is argue that this index
can be used to quantify the biodiversity of a habitat such as the number of species present, and
the abundance of each species. Furthermore, this index has a value between 0 and 1 (0 ≤ D ≤
1) that means lower values indicate more diversity while higher values depict less diversity.
D = ∑ (n/N)2
Which: D - Simpson index; n - the number of trees of a species; N - the number of all trees.
Sorensen’s index (Index of similarity)

The Sorensen index is a statistic used for comparing the similarity of two samples. SI
is determined by the following formula
SI=
Where: C = number of species occurring in both samples, A: the number of species in
A region, B: the number of species in B region
2.4.3.2. Interview.
Working with the experts about natural conservation, resources and environment in
local community and professionals specially in Ben En National Park

12


Interviewing local people and officials to evaluate the effect of local people on forest
plants and forest products
In addition, a set of questionnaires will be conducted to know where rare species, also
in this area in the past, whether the appearance of rare species have been planted or
regenerated, and whether policies in relation to rare species management and development are
in use this area

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CHAPTER III. RESERCH AREAS
3.1. Geographical Location
Ben En National Park is situated in districts of Nhu Thanh, and Nhu Xuan, Thanh Hoa
Province. The park is 46 kilometers southwest of Thanh Hoa city. The coordinates is: 19028’
to 19043’ North and 105025’ to 105038’ East.
Total area is 16.634 hectares, including 16 sub-region, Muc Lake and Hai Van
limestone areas, of which primitive forest covers 8.544 hectares, the core zone of the National
Park covers 15.800 ha, while the buffer zone covers around 12.000 ha. The park features a

3.000 hectares lake with 21 islets.

3.2. Topography
Ben En National Park is known as the ecological complex of stream, mountain, river,
lake and valleys with more than 16.000 ha of area and the plentiful plants and animals system.

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This is the homeland of the famous green ironwood in Viet Nam. In general, we clearly
observe some kinds of topography such as:
- Low mountain terrain.
Small areas, mainly appears in West, Southwest and East in the park. That is peak of a
range of mountains, namely Bu Dang – Nui Truong – Nui Dam – Nui Soa. The highest top is
Dam Mountain at 497m, and others are from 300 to 350m. The average slope about 250 – 300,
this terrain is relatively craggy with steep associate with limestone which has abundance of
caves and forest covers. Song Chang belongs to this topography.
- The slight slope of hill terrain
This terrain occupies the largest area of region and gathers mainly in the East, the
North and the West. The average slope is from 150 to 200, however, to the south and along the
sides of 15-highway, the topography becomes more steeply, at a mere 100 or lower than 100.
- Lake and Valley terrain
This one includes both Muc Lake and the valleys related to low mountains and hills.
In particular, Muc Lake is center for visiting, tourism the landscape in the Eastern Ben En
National Park. Moreover, the water level of lake ranges from 13m to 33m. The area of lake’s
surface about 2000- 3000ha and the average area is 2.281 ha. The lake is green all year round,
and it is quite and contains mysterious legends. It is said that when the earth and heaven were
chaotic, there was a giant squid, which was a the child of the King of the Sea coming here and
played until she forgot about time. When the water receded, the squid tried to get out but she
was trapped and the left point is available until now. Place of the dead squid created the Lake

Muc Ben en and the tentacle of the squid are the springs around. That is why the Lake is
named Song Muc with 4000 ha wide, tens of meters deep, with 21 islands to created the
fascinating landscape.

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3.3. Climate and Hydrology
According to the data from General Department of Meteorology and monitoring
station of hydro-meteorology in Nhu Xuan, Thanh Hoa province illustrates that: Ben En
National Park’s climate belongs to center of sub mid-land climate regions.
There are two distinctive season in each year: Rainy season begins in May and ends in
November that makes up 90 percent of the amount of rain in a year. Dry season starts in
December and culminates in April of next year. In general, from in April to June, Ben En
often is under the influence of Laos’ dry and hot wind which last about 19 or 22 days. The
winter monsoon starts in November and ends in March of next year. Besides, the southwest
monsoon is from April to October.
Ben En has two main rivers, namely Chang river in the West and Muc river in the
East. Basically, rivers and streams in Ben En have some such personal characteristics as:
Narrow and deep river-bed, flow’s velocity witnesses a significant growth in flood season and
gradual decrease in dry season.
The amount of water volume in Muc lake ranges from 250 to 400.000.000m3. This is
original of 2 big river and numerous rivers in around the area. Besides, the lake is not only
have a large area about 2.281 ha, but also it contributes to water to more than 10000 ha
agricultural lands which belong to Nhu Thanh, Nong Cong commune at downstream. In
addition, apart from controlling the water in upstream and providing irrigation or running
water in downstream, Muc Lake is where the preservation of cultural heritage, aquaculture
and valuable ecotourism development.
3.4. Forest resource
According to the scientific research of flora in Ben En in 2000, a total of 1357

vascular plant species were recorded in Ben En National Park, belonging to 902 genera and
195 families with sixth of higher plant sector such as: Psilotum nudum ( Psilotophyta),

16


Lycopodiella cernua (Lycopodiophyta), Equisetopsida or Sphenopsida ( Equisetophyta), Fern
( Polypodiophyta), the Flowering plant or angiosperms ( Angiospermae), Gymnosperm
(Gymnospermae).
Studies found that there are the couple of rare species in this park. So far, recovered
were 1.389 species of plants, 462 varieties of flora in the park, and 125 orders. Fauna
Several studies have been conducted to survey on the fauna of Ben En National Park.
There are 1.004 species of animals, 91 species mammals, 261 species of birds, 54 species of
reptiles, 31 species of amphibians, 68 species of fish and 499 species of insects ( Tordoff, A;
et al. 2000).
3.5. Characteristics of social economy.
There are two main towns, namely Yen Cat and Ben Sung in Ben En National Park
with combining 16 communes and 7 Armed Forces around the towns.
The total number of people in the park is about 41.672 people, belonging to 8.023
households. Meanwhile, male make up 48,5 percent and female occupy 51.5 percent. The vast
majority of people are belonged to King ethnic at about 50.2 percent, King’s people live
mainly with building brick houses. In addition, there are an abundance of their cultivation
such as: making garden, making crops, grazing cattle. This is followed by Thai people who
make up a mere 17.1 percent. However, Thai people also have the plenty of experience about
using water resource to serve swidden cultivation and specially, stilt house is a part of
historical and traditional relics. The third and the fourth position belong to Muong people and
Tho people, at 10.8 percent and 7.6 percent, respectively. The least number are other ethnic, at
negligible 4.3 percent with the average population density is 57 per capita/ km 2. The
population growth rate is 2.9 percent.

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CHAPTER IV. RESULTS AND DISCUSSION
4.1. Vegetation types in Ben En National Park and its characteristics
It is argue that the highest peak in Ben En National Park is merely about 490m, which
lead to all vegetation in the Parks belongs to lowland forest types (UNESCO 1973; Trung
2000; Lan et al. 2006). Obviously, there are huge distinctive between limestone’s vegetation
and other soil types’ vegetation, however, the vast majority of vegetation is significantly
influence by human activities. There are 4 main vegetation types in Ben En National Park:
Moist Tropical evergreen in lowland limestone forests, Moist tropical evergreen lowland
forests, Plantation forest and Agricultural land
4.1.1. Moist Tropical evergreen in lowland limestone forests
Slightly disturbed subtype
This forest types appears in the limestone hills at 450m where local people are
unauthorized for cutting and transporting timber trees because of the topography in here is
relatively dangerous with steep slopes and sharp edges. Specially, rare species settle down in
limestone hills which are located in Red Book of Vietnam as well as Red List of IUCN 2015
and they could face up with the verge of extinction. This forest type covers about 90 ha and
normally, foot paths in this forest type are extremely rare. Furthermore, this type can be found
in Thung Sen. Structure of this forest type includes four layers: the canopy layer is formed by
many trees with over 15m tall. There are several dominant species such as: Actinodaphne
obovata

(Nees)

Blume*,

Caryodanophsis

tonkinensis,

DysoxylumcauliflorumHiern*,

Ecliptaprostrata L, Saraca dives Pierre, Spondiaslakoensis Pierre*, Canarium album
Rausch.* ,Duabangagrandiflora (Roxb. Ex DC) Walp, Paviesia annamensis Pierre*,
Alangiumbarbatum (R. Br.)Baill. *, Symplocos poilanei, Castanopsis indica A.DC,
Castanopsis tonkinensis, Aglaia silvestris, Aphanamixis grandiflora and Aglaia spectabilis.
The sub-canopy layer is witnessed through small and moderate trees with the height of

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ranging from 1.5 m to 15m. These species are shade tolerant species, namely:
Paviesiaannamensis

Pierre*,

Diospyroseriantha Champ. ex

Caryodaphnopsis
Benth.*

,

tonkinensis

Ecliptaprostrata

(Lecomte)

L

Airy

Shaw,

. Diospyroseriantha

Champ.exBenth.*, Randiapycnantha Drake*, Aglaiaspectabilis (Miq.) S.S. Jain &Bennet*,
Saraca dives Pierre, Cinnamomum ovatum Allen, Litsea verticillata Hance, Sterculia Alata
Roxb, Actino daphnepilosa(Lam.) Merr, Canarium Bengalensis Guill, Canarium album
Rausch.*, Nephelium chryseum, Litsea baviensis Lecomte,Hudnocarpusanthelmintica Pierre,
Euphorbia tirucalli,

Acanthus

leucostachyus, Lithocarpus pseudosundaicus, Antidesma

hainanensis, Callicarpa dichotoma, Diospyros Montana, Acanthus leucostachyus, Knema
confert, Melientha suavis, Antidesma hainanensis, Antidesma acidum, Antidesma montanum,
Streblus macrophylla, Streblus indicus and Phoebe macrocarpa. Next, the shrub layer
includes only few species, like Dracaena cambodiana, Dracaena cochinchinensis, Antidesma
bunius, Streblus macrophylla, Miliusabalansae, Diospyros hirsuta, Litsea impressa,
Cryptocarya lenticellata and Millettia boniana. As for the herb layer is a combination of a
few species belonging to Balsaminaceae, Acanthaceae, Urticaceae, and Euphorbiaceae.
Heavily disturbed subtype on limestone
This forest type normally occurs in the limestone at 100m ~250m where the local
people could easily assess or transport after harvesting, e.g at Thu Lon Mountain region- Song
Chang, Ba Bai and some small areas in the center of the Park. As for the layer of the forest,
the forest’s structure consists of three distinctive layers, including the canopy layer, the shrub

layer and the herb layer. It is interesting that the canopy layer and the sub-canopy layer are
quite hard to distinguish. In terms of the canopy layer, it is composed mainly of Callicarpa
macrophylla, Callicarpa dichotoma, Acanthus ilicifolius, Diospyros montana, Lagerstroemia
calyculata, Pterospermum truncatolobatum, Pterospermum heterophyllum, Antidesma
montanum,

Acanthus

leucostachyus,

Diospyros

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hirsuta,

Koilodepas

longifolium,


Hydnocarpus anthelmintica, and Machilus bonii. Meanwhile, the shrub layer established by a
few speceis, namely: Streblus macrophylla, Antidesma bunius, Sterculia lanceolata, Randia
oxyodonta, Streblus macrophylla, Heritiera littoralis, Dracaena cambodiana, Dracaena
cochinchinensis, Acanthus leucostachyus, Diospyros hirsuta, and Aidia acuminatissima. The
last is the herb layer with a few species which belong to Acanthaceae, Balsaminaceae,
Euphorbiaceae, and Smilacaceae. Although the stands of this forest type have been exploited
dramatically in over period of time, the appearance of numerous efforts with the aim of
protecting the forest resource leading these gradually become stable.
Shrub-land associated with sparse timber trees on limestone.

In terms of shrub-land on limestone, the forest ranger and the staff in Ben En National
Park mentioning this vegetation type is not only the outcome of a heavy logging, but it is
influenced significantly by those activities as well. It takes place along the old logging road,
near village and distribute in Nui Dau Lon – Xuan Thai and Thu Lon – Song Chang.
Although the area of this forest type is quite small, at about 40 ha, the abundance of plant
species is relatively enormous. Some dominant species are Dracaena cambodiana, Dracaena
cochinchinensis, Memecylon edule, Ixorabalansae, Randia pycnantha, Callicarpa arborea,
Vitex trifolia, Acanthus ilicifolius, Desmos cochinchinensis, Uvaria micrantha, Alchornea
tiliifolia, Psychotria montana, Aporosa microcalyx and a few species belong to Urticaceae
4.1.2. Moist tropical evergreen lowland forests
Slightly disturbed subtype on ferralitic or alluvial soil
The formation of this forest type is related to some areas at ~250m where it is too
tough to transport the timber after exploiting because of the influence of topography or the
appearance of a station of the forest ranger. Basically, this forest type covers about more than
2000 ha. There are some signs of collecting Non-Timber-Forest-Products. This forest type
was found mainly in Thung Sen, Rung Giong region, Thu Lon and some areas in the Bo Cung

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