Relationship Berween Soil Porosity And Soil Compaction Under Castanopsis Boisii In Bac Giang And Hai Duong Province

MINISTRY OF AGRICULTURE AND RURAL DEVELOPMENT

VIETNAM FORESTRY UNIVERSITY

STUDENT THESIS

Relationship between Soil Porosity and Soil Compaction under

Castanopsis boisii in Bac Giang and Hai Duong Provinces

Major: Natural Resources Management

Code: D850101

Faculty: Forest Resources and Environmental Management

Student: Pham Vu Minh Student ID: 1153092194

Class: 56A Natural Resources Management Course: 2011 – 2015

Advanced Education Program

Developed in collaboration with Colorado State University, USA

Supervisor: Assoc. Prof. Dr. Phung Van Khoa

Ha Noi, November, 2015

Abstract

The aim of this research is to find a method to quickly define soil porosity in the

field based on measurement of soil compaction by using Daiki push cone-5553. The

research results showed that soil moisture has almost no relationship to soil compaction

and soil porosity because R2

equal 0.0182 and 0.0384 in order and Sig. >0.05, therefore

soil moisture should be ignored when building a look-up table of soil porosity based on

measurement of soil compaction. In contrast, soil compaction has a relatively strong

relationship to soil porosity because R2

= 0.6994 and Sig. = 0.00 < 0.05, hence this model

can be used to define soil porosity in the field. Nevertheless, this research is limited at

student thesis so this could happen errors. To summarize, it is necessary to do further

studies with larger scope of research to conduct data with variety of information, then

update a new look-up table of soil porosity to serve human researches.

Table of Content

I. INTRODUCTION........................................................................................... 1

II. GOAL AND (SPECIFIC) OBJECTIVES ................................................... 3

2.1. Goal: ......................................................................................................................3

2.2. Specific objectives:................................................................................................3

2.3. Hypothesis...........................................................................................................3

III. STUDY SITES AND METHODS ................................................................ 4

3.1. STUDY SITES......................................................................................................4

3.1.1. Luc Nam District, Bac Giang Province .............................................................4

3.1.2. Chi Linh District, Hai Duong Province .............................................................5

3.2. METHODS............................................................................................................7

3.2.1. Establish sample plots........................................................................................7

3.2.2. Collect soil samples ...........................................................................................7

3.2.3. Measure soil texture...........................................................................................8

3.2.4. Measure soil compaction ...................................................................................9

3.2.5. Measure soil moisture ........................................................................................9

3.2.6. Measure Bulk density ......................................................................................10

3.2.7. Measure particle density ..................................................................................10

3.2.8. Measure soil porosity.......................................................................................11

3.2.9. Measure soil organic matter.............................................................................12

3.2.10. Analyze soil data..............................................................................................13

IV. RESULTS................................................................................................... 14

4.1. Some physical indicators of top soil layer ..........................................................14

4.1.1. Soil Texture......................................................................................................14

4.1.2. Soil compaction ...............................................................................................14

4.1.3. Soil Moisture....................................................................................................17

4.1.4. Bulk Density ....................................................................................................19

4.1.5. Particle Density................................................................................................21

4.1.6. Soil Porosity.....................................................................................................23

4.1.7. Soil Organic Matter..........................................................................................25

4.2. Regression models between soil compaction, soil moisture, and soil porosity in

Bac Giang and Hai Duong provinces............................................................................27

4.2.1. A regression model between soil compaction and soil moisture under...........27

Castanopsis boisii in Bac Giang and Hai Duong provinces. ........................................27

4.2.2. A regression model between soil moisture and soil porosity under ................28

Castanopsis boisii forest in Bac Giang and Hai Duong provinces. ..............................28

4.2.3. A regression model between soil compaction and soil porosity under ...........29

Castanopsis boisii forest in Bac Giang and Hai Duong provinces. ..............................29

4.3. A look-up table to quickly define the soil porosity in the field based on

measurement of soil compaction ...................................................................................30

4.4. Answer of hypothesis..........................................................................................31

V. DISCUSSION................................................................................................ 33

5.1. Discussion ...........................................................................................................33

5.1.1. Soil moisture has no relationship with soil compaction and soil porosity ......33

5.2. Recommendation.................................................................................................34

VI. CONCLUSION .......................................................................................... 34

ACKNOWLEDGEMENTS ................................................................................. 35

VII. REFERENCES .......................................................................................... 36

VIII. Appendix................................................................................................. 38

List of Figures

Figure 3.1.1. Study sites in Bac Giang………………………………………………………...4

Figure 3.1.2. Study sites in Hai Duong……………………………………………….…….…5

Figure 3.2.3. Method of measuring soil texture……………………………………………….8

Figure 3.2.4. Daiki push-cone 5553……………………………………………………….…..9

Figure 4.2.1. Relationship between soil compaction and soil moisture in two study sites…...27

Figure 4.2.2. Relationship between soil moisture and soil porosity in two study sites………28

Figure 4.2.3. Relationship between soil compaction and soil porosity in two study sites……29

Figure 4.4.1. Relationship between soil porosity and soil compaction in Bac Giang……..…31

Figure 4.4.2. Relationship between soil porosity and soil compaction in Hai Duong………..31

Figure 8.1. Some pictures of study sites in Bac Giang………………….................................55

Figure 8.2. Some pictures of study sites in Hai Duong…………………………....................56

List of Tables

Table 4.1.2.1. Descriptive statistics of soil compaction in Bac Giang and Hai Duong……....15

Table 4.1.2.2. Soil compaction data in two Bac Giang anh Hai Duong……………………...16

Table 4.1.3.1. Descriptive statistics of soil moisture in Bac Giang and Hai Duong……….…17

Table 4.1.3.2. Soil moisture data in Bac giang and Hai Duong………………………………18

Table 4.1.4.1. Descriptive statistics of Bulk density in Bac Giang and Hai Duong…….……19

Table 4.1.4.2. Bulk density data in Bac Giang and Hai Duong………………………………20

Table 4.1.5.1. Descriptive statistics of particle density in Bac Giang and Hai Duong……….21

Table 4.1.5.2. Particle density data in Bac Giang and Hai Duong……………………………22

Table 4.1.6.1. Descriptive statistics of soil porosity in Bac Giang and Hai Duong………….23

Table 4.1.6.2. Soil porosity data in Bac Giang and Hai Duong…………………………..…..24

Table 4.1.7.1. Descriptive statistics of soil organic matter in Bac Giang and Hai Duong……25

Table 4.1.7.2. Soil organic matter data in Bac Giang and Hai Duong……………………..…26

Table 4.2.1. The two-way analysis of variance………………………………………….……27

Table 4.2.2. The two-way analysis of variance…………………………………………….....28

Table 4.2.3. The two-way analysis of variance……………………………………………….29

Table 4.3. A look-up table to quickly define the soil porosity in the field based on

measurement of soil compaction……………………………………………………………...30

Table 5.1.1. Relationship between some physical indicators in Bac Giang and Hai Duong…33

Table 8.1. Soil used to measure Bulk density………………………………………………...38

Table 8.2. Soil used to measure particle density…………………………………………...…42

Table 8.3. Coordinate point and elevation of soil samples……………………………...……46

Table 8.4. Soil used to measure soil organic matter……………………………………….…48

Table 8.5. Questionnaire for interview……………………………………………………….51