Structural Characteristics Of Tropical Broadleaves Stands Under Effect Of Conventional And Low Impact Logging Plot In Truong Son Forest Enterprise Quang Binh Province

ACKNOWLEDGMENT

During months of conducting this working, I gained availed of encouragements

and assistance from many people without whom this thesis would have never been

conducted.

First and foremost, I would like to express my gratefulness to Dr. Nguyen Hong

Hai for constant support to each step of my thesis working, giving me motives and

enthusiasm as well as a wealth of knowledge. The guidance was really clear with vivid

images and detailed illustration, which facilitated me a lot in thesis project, in another

place, I would like to thank the Administration of Vietnam Forestry University,

Faculty of Forest Resources and Environmental Management, Department of

Environmental with sincere gratitude for enabling us all best to complete the

graduation thesis.

Also, I sincerely express my thankfulness to many local people and authorities,

both of whom untold assist me in collecting data and many other related procedures

Finally, I also thank my family and all my friends, partners for best effort me

the best facilitations to accomplish the thesis within expectations.

Thank you!

Xuan Mai, 2

nd October 2019 Student

Nguyen Thi Hong Nhung

TABLE OF CONTENT

ACKNOWLEDGMENT .................................................................................... 1

TABLE OF CONTENT ..................................................................................... 2

LIST OF TABLES ............................................................................................. 4

LIST OF FIGURES............................................................................................ 5

ABSTRACT....................................................................................................... 1

CHAPTER 1 - INTRODUCTION...................................................................... 2

1.1. Forest and forestry in the world................................................................. 2

1.2. Forest and forestry in Viet Nam ................................................................ 2

1.3. Conventional Logging (CL) ...................................................................... 3

1.4. Low Impact Logging (LIL)....................................................................... 3

1.5. Studying in Forest structure ...................................................................... 4

CHAPTER 2 - GOALS, OBJECTIVES AND METHODOLOGY..................... 6

2.1. Goals........................................................................................................... 6

2.2. Objectives.................................................................................................... 6

2.3. Methodology ............................................................................................... 6

2.3.1. Data collection.......................................................................................... 6

2.3.2. Data analysis ............................................................................................ 7

CHAPTER 3 - NATUAL AND SOCIO-ECONOMIC CONDITION OF THE

STUDY REGION ............................................................................................ 11

3.1. Natural condition....................................................................................... 11

3.2. Socio-economical condition ...................................................................... 15

CHAPTER 4 - RESULTS AND DISCUSSIONS............................................. 17

4.1 Forest stand properties................................................................................ 17

4.1.1. Main characteristics of two forest stands ................................................ 17

4.1.2. Diameter distribution.............................................................................. 19

4.1.3. Characteristics of tree individuals at life stages ...................................... 20

4.2. Tree species composition........................................................................... 21

4.2.1. Tree species composition of two plots.................................................... 22

4.2.2. Tree species compositions at life stages.................................................. 25

4.3. Species diversity........................................................................................ 26

4.3.1. Species diversity in two plots ................................................................. 26

4.3.2. Species diversity at life stages in two plots............................................. 27

4.4. Spatial distribution .................................................................................... 28

4.4.1. Distribution of trees by life stages .......................................................... 28

4.4.2. Spatial distribution of dominant tree species........................................... 30

4.5. Some recommendations for sustainable forest management at Truong Son

Forest Enterprise. ............................................................................................. 33

4.5.1. Management solutions........................................................................... 34

4.5.2. Policy solutions ..................................................................................... 34

4.5.3. Technical solution .................................................................................. 34

CHAPTER 5 – CONCLUSION ....................................................................... 36

5.1. Forest structure stand................................................................................. 36

5.2. Species composition .................................................................................. 36

5.3. Species diversity........................................................................................ 37

5.4. Spatial distribution .................................................................................... 37

5.5. Proposing management solutions............................................................... 38

REFERENCE

APPENDIX

LIST OF TABLES

Table 4.1. Structural characteristics of tree species in LIL plot......................... 17

Table 4.2. Structural characteristics of tree species in CL plot.......................... 18

Table 4.3. The most dominant tree species in LIL plot .................................... 22

Table 4.4. The most dominant tree species in CL plot ...................................... 23

Table 4.5. The most dominant tree species base on life stages in two plots ..... 25

Table 4.6. Summary of diversity measures for the two plots ............................ 27

Table 4.7. Summary of diversity measures for the study plots at life stage levels

......................................................................................................................... 28

LIST OF FIGURES

Figure 3.1 The location of the study site in Quang Binh Province .................... 12

Figure 3.2 Climate graph by month in Quang Ninh district, Quang Binh

province ........................................................................................................... 13

Figure 3.3 Average temperature Quang Ninh district, Quang Binh province .... 14

Figure 4.1 Frequency of tree individuals and tree DBH in LIL plot.................. 19

Figure 4.2 Frequency tree individuals and tree DBH in CL plot ....................... 20

Figure 4.3 Spatial distributions of life stages in LIL plot analyzed by the

Ripley’s L function........................................................................................... 28

Figure 4.4 Spatial distributions of life stages in CL plot analyzed by the Ripley’s

L function......................................................................................................... 29

Figure 4.5: Spatial distributions of seven dominant species in LIL plot analyzed

by the Ripley’s L function. ............................................................................... 31

Figure 4.6: Spatial distributions of seven dominant species in CL plot analyzed

by the Ripley’s L function. ............................................................................... 33

1

ABSTRACT

This study has aimed to show some structural characteristics of tropical

broadleaves that stands under the effect of conventional and low impact logging in

Truong Son Forest Enterprise, Quang Binh Province. A total of 2 plots of 100m x

50m each placed in two forest states were surveyed species name, diameter, height,

relative coordinates. We calculated and described structural parameters such as DBH

dominance and species index, tree density, frequency distribution, and tree diameter

and height data by Paleontological Statistics and Microsoft Excel softwares. The

results show that: most of studied species were found highly mixed with other species.

The number of trees per life stages and density of the forest state conventional logging

concentrated on all diameter levels form sapling, juvenile, and adult, suggesting that

this forested state will focus on all trees of economic value in Truong Son Forest

Enterprise, while in the low impact logging concentrated mostly on diameter of more

than 30 cm to keep the immature seedlings alive for future crops. The number of trees

in each life stage is inversely proportional to each other, the number of individuals

decreases when the diameter becomes larger. Species composition were very seriously

affected because number of species in the life stage all changed. The most important

species found in both two forest states were G.pierrei, T.javanica, L. glutinosa, B.

tonkinensis, P. cerasoides. About spatial distribution of two plot mainly clustered

distribution but some species that are completely randomly distributed without the

cluster distribution like G. pierrei. The spatial structural parameter offers direct

information and valuable about spatial structure of forest stand. That information can

be used in thinning of sustainable forest management, modeling and restoration.

Key words: Forest enterprise, forest stand properties, LIL plot, CL plot,

tropical broadleaves, tree species composition, tree species diversity, spatial

distribution.