ARTICLE

mJ¥;tt~:ii;~,t (Journal of the Japanese Society of Coastal Forest) 20 (1)1-8, 2021

Direction of conservation management of coastal forests from the residents'
evaluation of their multifaceted functions in Okinawa Prefecture
Barn H.N. Razafindrabe 1, Minoru Okada2 and Shoji Inoue3
Abstract: This study aims to evaluate the multifaceted functions of coastal forests as well as the impact of tsunamison the community's perception of coastal forests to understand the future direction of coastal forest conservation. The
study was conducted in Ishigaki (three locations) and on Okinawa Main Island (two locations). Questionnaire surveys
were conducted at each site. After an evaluation of the different scales, with scores from 1 to 5, an exploratory factor
analysis was conducted regarding perceptions related to the 'Currently-felt extent' (F-score), 'Expected extent in the
future' (E-score), and 'Dissatisfaction with coastal forests' (Demerits). At-test (at the 5% level) was conducted todetermine whether there was a significant difference between F-score, E-score, and Demerits scales. Overall, E-scoreshowed significantly higher values than F-score. However, no significant difference was found for the scale 'Protectionof a house against typhoons'. Regarding Demerits, the average value of 'Garbage dumping site' was significantly
higher than the other scales. When comparing areas with and without coastal forests, the only significant difference
was in the 'Blocking sea view', showing significantly lower values in areas with coastal forests. The existence ofdifferences in evaluation and perception in a target region is regarded as a crucial element to be recognized for more
effective conservation and management of coastal forests.

1 Introduction
After the tsunami caused by the 2011 Great East Japan
Earthquake, attention was paid to the reevaluation of thefunction of coastal forests against tsunamis. In the Tohoku
region, a project has been initiated for the restoration ofcoastal forests damaged by the tsunami. Along withincreasing awareness of disaster prevention against
tsunamis, various areas began to review the use of coastal
forests (MAFF 2012). However, cooperation with and theopinions of the local people living around the coastal
forest are unavoidable in future planning and managementof coastal forests. Thus, it is equally important to have acoastal forest that is cared for and protected by residents
while committing to its maintenance and benefitting fromits resources.
Coastal forests were created with the main purpose ofdisaster prevention functions such as sand-drift prevention
and windbreak. Recently, however, they have shownvaried multifaceted function tendencies (Okada 2020).
Taking advantage of this multifaceted function, a coastal
forest that has a production capability function in 'normal
times,' functioning as seawalls and mitigating otherphysical hazards in 'emergency times,' also needs to beproperly recognized. Therefore, there is a need toformulate a conservation and utilization plan that makes
use of the multifaceted functions of coastal forests,
concerning residents' current perceptions of thoseresources. It is thus necessary to clarify the current levelof awareness of residents towards coastal forests and their
1 Faculty of Agriculture, University of the Ryukyus, 1
Senbaru, Nishihara Town, Okinawa Prefecture, 9030213, Japan
2 School of Commerce, Senshu University, 3-8 KandaJimbocho Chiyoda-ku, Tokyo, 101-8425, Japan
3 University of the Ryukyus, 1 Senbaru, Nishihara Town,
Okinawa Prefecture, 903-0213, Japan*Corresponding author: okada@isc.senshu-u.ac.jp- 1-

multifaceted functions. Moreover, to be more effective,
the future direction of resource use and conservation planshould reflect the evaluation of residents, thereby
recognizing this resource as a 'coastal forest of thecommunity.'
Therefore, in this study, we will evaluate the multifaceted functions of coastal forests as well as the impactof tsunamis on the community's perception of coastal
forests to understand what the future direction of coastal
forest conservation should be.
2 Materials and Methods
2.1 Study sites
The study was conducted on Ishigaki Island (hereinafterreferred to as Ishigaki), which was heavily damaged by alarge-scale tsunami (the 1771 Meiwa tsunami). For
comparison, a second study area, Okinawa Main Island(hereinafter referred to as Okinawa) was selected. Bothsites belong to the same prefecture (Okinawa Prefecture).
Questionnaire surveys were conducted at threelocations in Ishigaki (Miyara-Shiraho, Inoda, andArakawa) and two locations in Okinawa (Toubaru, Afuso ).
More detailed information on the questionnaire survey
locations, coastal forest location, and descriptions of theircharacteristics are shown in Figure 1. The results of ageneral survey of planted tree species in the surveyed
locations are shown in Table 1.
Questionnaire survey sites on Okinawa Main Island
were chosen among those considered by Okada et al.
(2012), which had coastal forests within their region.
Consequently, the study demonstrated the differences inawareness and perceptions before and after the major
impact of the Great East Japan Earthquake and Tsunami.
Table 2 shows the run-up height of the 1771 Meiwa
tsunami and estimated tsunami inundation height at eachlocation based on the inputs from the Great East Japan
Earthquake according to Okinawa Prefecture (2015).

lshigaki

Okinawa

E124 ° 09'

N

N

Cl)

Cl)

0

~
20km

0

5km

E127 ° 40'

N26 ° 12'N

CD

• Forest and Treesr···1 Settlements,.... ; and Building Sites-

N

Main Roads
National roads
Prefectural roads- - Other Roads

CD

LJOOm
Figure 1: Location and overview of the surveyed area
Table 1: Tree species composition of the coastal forest
in the surveyed area
Shiraho lnoda@
Ca/ophyllum inophyllum L.
@
Casuarina equisetifolia J. et G. Forst.
Garcinia subelliptica Merr.
0
Morus australis Pair
0
Terminalia catappa L.
0@
Thespesia populnea Soland.
0
Messerschmidtia argentea Johnston
0
Pandanus odoratissimus L.f
0@ : main tree species

2.1.1 Description of the 1771 Meiwa tsunami
The 1771 Meiwa tsunami was caused by the M7.4
earthquake centered on the Sakishima Islands in the
Okinawa Prefecture around 8:00 am on April 24, 1771.
This major tsunami caused approximately 12,000
casualties. Human casualty conditions in the surveyedsites are shown in Figure 2.
Research on tsunamis has been conducted since thediscovery of ancient documents describing the Meiwa
Great Tsunami in the 1920s and following thereorganization of ancient records leading to the-2-i4if:1¥#~~~.t (Journal of the Japanese Society of Coastal Forest) 20 (1)publication titled 'The Great Meiwa Tsunami ofYaeyama'
in 1968 (Makino, 1968). The maximum run-up height of
the tsunami was reported to be 30 m or more (Japan
Meteorological Agency, 2012; Okinawa Prefecture, 2015).
The recorded and estimated values (Goto, 2012) of the old
run-up height in the study area are shown in Table 2.
In addition, Ishigaki City sets April 24th every year asa citizen disaster prevention day and holds the Meiwa
Tsunami Evacuees Memorial Festival to commemorate
the victims' memorial service and raise disasterprevention awareness (Ishigaki City, 2020). On Okinawa
Main Island, prior to the Great East Japan Earthquake,discussion about the tsunami was negligible, unlike the

1-8, 2021

Ishigaki Island, where local residents were more familiar
with the tsunami (Goto, 2020). This has been reported tobe due to the culture of oral tradition within families in
Ishigaki, citing the 'mermaid' legend as a typical exampleof the tsunami lore related to the Meiwa tsunami. Morethan 88% of the respondents reported that they were aware
about the 1771 Meiwa tsunami (before the Great East
Japan Earthquake) and approximately 10% reported
becoming aware after the Great East Japan Earthquake(Figure 3). Goto (2020) also reported the existence ofother tsunami traditions in the Yaeyama Islands that are
related to the Meiwa tsunami.
2.1.2 Impacts of the 2011 off the Pacific coast of Tohoku
earthquake-led tsunami in the Okinawa region
The impacts of the tsunami from the 2011 off the Pacificcoast of Tohoku earthquake on March 11, 2011, was also
observed in Okinawa Prefecture. The first wave wasobserved at the observation points in the prefecture
approximately 3 h after the earthquake. Table 2 shows the
maximum inundation height around the study area (Japan
Meteorological Agency 2012).
Following the event, Okinawa Prefecture released the
maximum undulation height and maximum run-up height(Table 2) of the estimated tsunami in 2015 as a tsunami
inundation assumption (Okinawa Prefecture 2015). In
addition, in the "Tsunami Disaster Prevention Manual" forthe Yaeyama region, including Ishigaki Island, the effectof coastal forests (tidal forests) was introduced to reduce
the energy of the tsunami and prevent drifting objects as atsunami disaster prevention measure (Yaeyama Regional
Disaster Prevention Liaison Committee 2013).

MiyaraShirahoArakawa

I• Victim D Survivor
Goto(2020)

Figure 2: Damage caused by the Meiwa tsunami
in the surveyed area

2.2 Methods
For the questionnaire survey, public halls andneighborhood associations in each district were asked to
distribute and collect survey questionnaires from residents.
The survey period was from November 2012 to January
2013. In the questionnaire, the scale for each function of
the multifaceted functions of coastal forests was the same

• Yes (before the Great East Japan Earthquake)• Yes (after the Great East Japan Earthquake)• No

Figure 3: Knowledge of the 1771 Meiwa tsunami
before and after the Great East Japan
Earthquake

Table 2: Information on tsunami and related damages in the surveyed area
Islands andSurvey Arealshigaki
MiyaraShiraholnoda
Arakawa
Okinawa
Afuso
Toubaru

Runup height of
the 1771 Meiwa tsunami (m) *1
Ancient document Goto(2012)

Maximum Inundation heightof the 2011 off the pacific coastof Tohoku earthquake tsunami(m)*2

Maximum Runup heightof the expected tsunami(m)*3

0.23* 28
85.4
59.9
10.7
8.2

21.4 - 33.2
19.2- 25.1
>7.0
3.6-10.0

24.2
23.4
38.4
14.9

*38

0.60 * 2b
5.6
9.3*3b

*1 Goto(2012)* Japan Meteorological Agency (2012) * lshigaki Port* lshigaki Port
* Okinawa Prefecture(2015)
2

2•

3

3•

* Naha* Hentona

-3-

2b

3b

Table 3: Description of each evaluation scale andtheir respective scores

Table 5: Number ofrespondents to the questionnaire

scale
score

1
2
3
4
5

F-scoreE-scoreDemerits
No feelings
No expectations
Low feelings
Low expectations
No opinion
Some feelings
Some expectations
Great feelings
Great expectations

Islands

Survey Coastal
Area Forest

lshigaki

MiyaraShiraholnoda
Arakawa

Okinawa Afuso

Toubaru

N

2011*

0
0
0

} 37

X

0
0

2012

31
30

39
31
14
20

* Okada(2012)
Table 4: List of variables used in the evaluation in both sites
F-scoreE-scoreOkinawalshigakiWindbreaking
Capturing salt from sea spray
Improving scenery
Protection for a house against typhoon
Blown sand control
Mitigating big waves such as tsunami
Observing olants
Protection from strong sunshine
Habitat of animals and plants
Resting place under the shade of trees
Source of materials used in everyday life
Source offood
Use as firewood
Capturing dust
Creating a local landscapeAbsorbing CO 2 in the air
Forest therapifor healing
Place for teaching about nature, animals, and plants* Okada(2012)2011* 20120o·····················o·········

0
O
0
0
0
O
0
0
0
0
0
0
0
0
0
0
0

0
0
0
0
0

0
0
0
0
0

0
0
0
0
0
0
0
0
0
0
0
0

as in the questionnaire survey conducted by Okada et al.
(2012) in February 2011. In Ishigaki Island, 'Currently felt
extent' (hereinafter referred to as the F-Score), 'Expected
extent in the future' (hereinafter referred to as E-Score),and 'Dissatisfaction with coastal forests' (hereinafterreferred to as Demerits) were evaluated in five scales andscored from 1 to 5 (Table 3). The number of evaluation
units in the F-score and E-score was 18 (including
parameters such as, 'Capturing salt from sea spray', 'Wind
breaking ability', and 'Improving the scenery'), while
those of the Demerits were 14 (including, 'Blocking sea
view', and 'Hindering cool wind') (Table 3).
On Okinawa main island, with regard to the F-score andE-score, the evaluation concerned the six highest
representative scales selected from those used in Ishigaki
Island based on Okada et al. (2012) (Table 4). Table 5shows the number of respondents at each distribution site,
showing three sites 'with coastal forests' in Ishigaki, andtwo sites on Okinawa Island. A statistically significant
difference in evaluation scores between locations wasfound between Miyara-Shiraho and Inoda on 7 of the 50
scales; no significant difference was found in Okinawa.
To determine the potential evaluation criteria, as well as
the underlying latent variables, an exploratory factor
analysis with Promax rotation (oblique rotation) was
performed on each scale of the F-score, E-score, andDemerits.

Demerits

Aggravation of scenery
Increase in shade, barring sunlight
Blocking sea view
Hinders cool wind
Closed atmosphere
Difficulty in walking because of complicated plants
Habitat for many insects and animals
Bad scenery because of withered trees
Threat of falling branches
Threat by being large
Increase in work burden such as processingof fallen leaves and branches
Fear or insecurity because of the peace
Difficulty in walking because of prickly plants
Garbage dumping site

3 Results
3.1 Extraction of underlying latent variables and theirmean values
The exploratory factor analysis results (Table 6)
showed that the F-score was classified into 3 factors, theE-score 4 factors, and the Demerits into 3 factors (basedon an eigenvalue of 1). The latent evaluation scale wasinterpreted according to the scale with a large factor
loading (>10.31) for each factor. Factor 1 was interpreted
as a disaster prevention function, Factor 2 as a health restfunction, and Factor 3 as a resource supply function.
In E-score, Factor 1 is a health rest function, Factor 2 isa resource supply function, Factor 3 is a disasterprevention function against the sea breeze, and Factor 4 isa function with a large difference between the evaluation
values of the F-score and E-score (mean values). All the
top five scales with large value differences are included.
In the Demerits, Factor 1 was interpreted as an apparent
problem, Factor 2 was a litter problem, and Factor 3 wasa problem of the adverse effects on daily life.
The mean evaluation values of each F-score and Escore scale are shown in Figure 4. Overall, the E-scoreshowed significantly (t-test at 5% level) higher values
compared to the F-score. However, no significant
difference was found for 'Protection for a house against-4-

iilJ:1¥#~~~.t (Journal of the Japanese Society of Coastal Forest) 20 (1)1-8, 2021

Table 6: Result of factor analysis for each scale
factor loading

F-scorefood

0.880 -0.191
0.731 0.128
0.583 0.007
0.523 0.148
0.515 0.183
0.499
0.449
0.383
0.078
-0.115
0.116
0.276
0.035
0.203
0.282
-0.132-0.0790.068

eigenvalue

8.1627

sand

salt

co,

tsunamityphoon

wind
teach
dust
scenery
shade
habitatlandscapeobservingsunshine
therapyfirewoodmaterials

communality

0.625
0.596
0.512
0.465
0.396
0.404
0.678
0.451
0.632
0.616
0.569
0.588
0.483
0.473
0.539
0.807
0.768
0.678

factor loading-~-~~-~@~-®~ communality

E-scoreCD

0.769 0.115 0.121 -0.200
observing
0.744 0.174 -0.015 -0.091
scenery
0.585 -0.034 0.176 0.048
landscape0.555 -0.040 0.020 0.279
therapy
0.537 -0.007 -0.0721 0.3731
0.483 0.092 -0.006 0.312
teachhabitat0.435 0.000 0.243 0.014
materials-0.099 -0.042
0.003 0.042
firewood
food-0.046 0.023
dust
0.133 I 0.427 I
salt
1.008 -0.023
Wind
0.462 0.080
0.396 0.176
typhoontsunami0.017 0.895
co,
0.166 0.518
sand
0.297
7
sunshine
0.240 0.244 0.278 0.214
eigenvalue 6.9875 2.2068 1.2890 1.1117~~~i~i~,i~on 29.182 17.409 20.239 23.419
shade

2.216 1.0821~~i~if,~,~on 31.841 35.416 26.161

0.628
0.616
0.483
0.529
0.564
0.533
0.350
0.602
1.000
0.407
0.439
0.961
0.384
0.335
0.713
0.542
0.396
0.490

Demerits

factor loading

communality

scenery
0. 776 0.020 0.023
shade
0.732 0.122 -0.127
sea view
0. 707 -0.123 0.035
wind
0.638 -0.001 -0.109
closed
0.554 0.0471 0.3531
0.419 0.132 0.384
walking
habitat0.395 0.176 0.053
withered
0.341 0.238 0.219
branches
0.001 0.954 -0.005
large-0.004 0.943 0.048
work
0.218 0.334 0.263
insecurity
0.041 -0.083 0.873:
pnckly plants 0 027 0.069 0.643
dumping-0:154 0.077 0.515

I

0.646
0.519
0.449
0.321
0.755
0.683
0.306
0.474
0.906
0.935
0.487
0.738
0.493
0.214

eigenvalue 6.8141 1.2139 1.1251~~~~i~~~on 39.177 31.118 35.081

typhoon' (noted as 'typhoon' in
Figure 4). When divided into villages
I-testwith and without coastal forests, theFactorp<0.05 ns
number of scales for which there was-+-oF-score
F-score2 3 4 52 3 4 51
2 3 4 5E-score ··•·· ••,t;,••no significant difference by the t-test
CDOO
sand
between the F-score and E-score
salt
showed 5 scales for "with coastal
CO 2
forest", and 7 scales with "no coastal
tsunamiforest". There was no significant
typhoondifference among villages withwind
coastal forests (with the 'health rest
teach
dust
function') and without coastal forest
scenery(with resource supply function).
shade
Figure 5 shows the average value
habitatofeach scale in the Demerits and thelandscapedifference between the presence andobservingabsence of coastal forests. As a result,sunshine
therapy
the average value of the "Garbage
firewood
dumping site (noted as 'dump')" wasmaterials
significantly higher than other scales.
food
When comparing areas with andwithout coastal forests, a significant
Figure 4: Mean evaluation values of each scale ofF-score and E-score
difference by the t-test (5% level) was
observed
onlyin'Blockingsea view' (sea view), showing
Score (average)
significantly
lower
valuesinareas 'with coastal forests'.
Whole
Coastal forest
Score (average)
Coastal forest
With
Without

Factor(D(Z)@

2

3

4

51

2

3

4

5

ilf i

1;1
~cilx

scenery
falling branches
large
work
insecurity
prickly plants
dump

i:)

~

g

lit
i'

p<0.05withwithoutns-•· ···X··-D·

3.2 Comparison of evaluation values between Ishigaki
and Okinawa
To investigate the functional evaluation between
Ishigaki and Okinawa, the mean evaluation values of thesix overlapping scales were compared (Table 7). As aresult, no significant difference was found between
Ishigaki and Okinawa at any scale by the t-test. However,looking at the difference between F-score and E-score oneach island, Ishigaki confirmed a significant difference by
the t-test (5% level) on all scales except for the 'Protectionof a house against a typhoon (noted as 'typhoon')'.
Although the E-Score had a higher evaluation value in
Ishigaki, no significant difference was observed in
Okinawa.

··M··

Figure 5: Mean evaluation values of each scale ofDemerits

3.3 Comparison of evaluation values before and after
the occurrence of the tsunami from the 2011 off the Pacificcoast of Tohoku earthquake-5-

Table 7: Mean evaluation values of each scale for F-score and E-score
score (average)lshigakiOkinawa
F-score E-score F-score E-score
4.31
4.43
wind
4.34
4.58
salt
4.28
4.29
4.54
4.03
scenery
4.04
4.11
4.06
3.89
typhoon
4.54
4.59
4.33
4.35
sand
4.33
4.23
4.40
4.25
tsunami
3.95
3.77
4.03
4.22
*: p>0.05, **: p>0.01

t-testlshigaki - Okinawa
F-score E-score

F-score - E-scorelshigaki Okinawa
**
*
**
*
**

Table 8: Comparison of 2011 and 2012 evaluation values (average values) in Okinawascore (average)
2011
2012
F-score E-score F-score E-score
4.50
4.31
wind
4.56
4.26
4.00
salt
4.51
4.49
4.35
scenery
3.81
3.86
4.12
4.08
typhoon
4.63
4.42
4.42
4.50
sand
4.19
4.42
4.26
4.42
tsunami
4.25
4.12
3.96
4.33
*: p>0.05, ••: p>0.01

To understand the difference between the evaluation
values before and after the tsunami from the 2011 off the
Pacific coast of Tohoku earthquake (2011.3.11),
evaluation values between the 2011 and 2012 F-score andE-Score evaluation values (mean values) were comparedusing at-test (Table 8). As a result, there was a significant
difference between the 2011 and 2012 evaluation values
in the F-score 'salt', 'scenery', and 'typhoon' values.
However, there was no significant difference in the Escore. Regarding the comparison (by t-test) between theF-score and E-score, there was a significant difference in'wind' and 'typhoon' in 2011 but no significant differencein 2012.
4 Discussion and Conclusions
4.1 Evaluation of the multi-dimensional function ofcoastal forest by residents
Regarding the evaluation of the multifaceted functionsof coastal forests, from the extraction of latent evaluation
scales, it was found that the residents' perceptions wereroughly divided into 'Disaster prevention function','Health rest function', and 'Natural resource supply
function'. This finding is in line with previous studies(Okada et al. 2012; Okada 2015).
Moreover, in the E-score, a latent evaluation factor
noted as a 'function with a large difference in evaluationfrom the F-score' was included. This function should betreated separately from the classification of the overall
functions by the local residents. It might also be effective
to focus on functions with large factor loadings,
prioritizing them over other functions.
4.2 Difference in the evaluation of coastal forests byregionConsidering the differences in evaluation between

t-test2011 - 2012
F-score E-score***

F-score - E-score
2011
2012
**

*

Ishigaki and Okinawa, there was no statisticallysignificant difference in the evaluation values of eachfunction. In Ishigaki, except for the 'typhoon' function,
there were significant differences in all functions between
the F-score and E-score. No significant difference wasfound for Okinawa.
Based on the evaluation results found in Okinawa andIshigaki, the direction of coastal forest conservation isdifferent for the two islands. While the former tends
toward improvement, the latter gives importance tomaintenance. Assuming that the evaluation value of eachfunction is high in both regions, the influencing factor thatmight have led to the above difference between the tworegions is the 'further expectations' found in Ishigaki.
In addition, as the influence of the Meiwa Tsunami has
been present in Ishigaki, a stronger perception of threats
from the sea is considered an important factor. In fact,
among the opinions mentioned by survey respondents inthe questionnaire figure, a description noted that "thecoastal forest is being managed using the lessons learned
from the Meiwa tsunami". Although it is difficult to derivea clear relationship with the results of this survey, it canillustrate the importance of this factor. Therefore, theassociation of culture and tradition with coastal forest
conservation management 1s effective in raisingawareness of the region.
4.3 Changes in evaluation before and after the Great
East Japan earthquake
Before and after the Great East Japan Earthquake, there
was a change in evaluation values in the F-score but nostatistically significant change was found in the E-score.
From this finding, it is highly possible that information on
major impacts (such as the tsunami in this study) will bereflected in the current assessment of coastal forests.

-6-

i4if:1¥#~~~.t (Journal of the Japanese Society of Coastal Forest) 20 (1)However, future expectations may not have a similar trend.
If expectations for coastal forest functions can be known
in a timely manner and if the direction of conservation
management of coastal forests is set on that basis, it isbelieved that the occurrence probability of major
problems or the need for a necessary redirection ofconservation management would be less expected.
Moreover, looking at the change in the evaluation
values in F-score, 'salt' and 'typhoon' showed lower
evaluation values, coinciding with the period of
occurrence of typhoon No. 2 in May 2011 and typhoons
No.15, No.16, andNo.17 from August to September 2012,
which caused enormous damage to the Okinawa
Prefecture (The Okinawa Times 2011; The Asahi
Shimbun 2013). Lower evaluation values are believed tobe due to the enormous damage caused by these typhoons,
greatly affecting the perception of the residents.
Although the tsunami generated by the Great East Japan
Earthquake was felt in Okinawa Prefecture, the direct
damage was less perceived than that of the typhoons. Thismight have affected the residents' perception of the'tsunami' variable and resulted in the absence of perceived
change in the evaluation. However, the evaluation value
itself is high for both the F-score and E-score. As shownin various comments and opinions in the free answer
section of the questionnaire, the threat from the tsunami
remains crucial for the region.
4.4 Direction of conservation management of coastal
forests based on evaluation results
Demerits were classified into 'visual problem','deciduous litter problem', and 'impact on daily life' by
extracting latent evaluation scales. Improving the listed
demerits is largely related to improving the evaluation ofresidents to coastal forests. Setting a direction for eachissue and confirming which category includes the issues
mentioned in that area enables efficient responses andaddresses issues that were not given in this questionnaire.
In addition, regarding the multi-faceted functions ofcoastal forests, it is crucial to set which functions should
be given priority and what direction should be taken to
implement the conservation management of coastal
forests. Similar to previous studies (Okada et al. 2012;
Okada 2015), the findings from this study showed that itis effective to set the improvement direction for eachclassification of "disaster prevention function", "healthrest function" and "natural resource supply function". In
addition to this, the extent of evaluation values (meanvalues) of each scale, combined with the existence orabsence of a difference between F-score and E-score was

the main focus in this study.
Regarding the extent of evaluation values, the scores
given by the residents in their evaluation were simply
categorized based on whether they were lower or higher
than 3. Scores lower than 3 correspond to 'no feelings','low feelings' and 'no opinion' with regard to F-score andDemerits; and 'no expectations', 'low expectations', or'no opinions' with regard to E-score. Scores higher than 3
indicate those corresponding to "some feelings', 'great
feelings' with regard to F-score and Demerits; and 'some
expectations', 'great expectations' with regard to E-score(as shown in Table 3).
This approach can be improved in future studies toreflect residents' perceptions in a more effective way.
Moreover, the evaluation differences were classified
according to the existence of a statistically significant
difference between the mean F-score and E-score values.
As the E-score was higher than the F-score for all scales,
it was assumed that the evaluation of coastal forests would
be improved by improving the scales that differed. The
direction of improvement and its priority were thus set by
multiplying the above two viewpoints, shown as types 1,
2, 3, and 4 (Table 9).
As shown in Table 9, because Type 1 has a highevaluation value, thereby showing a larger evaluationdifference, it was interpreted as a function that should be
improved in the future with a high priority. Specifically,
Factor 4 of the E-score, including the 'tsunami' variablecorresponds to this group. Type 2 showed a highevaluation value without a significant difference inevaluation. Thus, it was interpreted as a function thatshould maintain the current status setting it as a highpriority because the current evaluation was high (the caseof 'typhoon'). As Type 3 has a low evaluation value witha significant evaluation difference, it was interpreted as afunction with the potential to enhance its evaluation in the
future; the current evaluation was low. Therefore, thepriority was set as medium. This concerns the Factor 2 of
the E-score, namely, the 'natural resource supply
function'. In the case of Type 4, where there was a low
evaluation value characterized by the inexistence ofevaluation difference, it was interpreted as a function thatis not particularly required to be targeted for improvement,setting it as one with low priority. This was the case of'food' in areas with coastal forests.
The approach addressed in this study appears to beeffective when setting the direction of coastal forest
conservation based on local residents' evaluations. The
existence of differences in evaluation and perception in atarget region is regarded as a crucial element to be

Table 9: Direction of coastal forest conservation management from the viewpoint of evaluation
Type

2
3
4

Evaluation
score
High
High
Low
Low

Differenceofevaluation

1-8, 2021

Directionalityof improvement

necessary improvement
significant
not significant
keepsignificant
effective improvement
not significant(improvement)-7-

Priorityhighhighmediumlow

Example offunctions andfactors (E-score)factor4
typhoonfactor 3
food (existence)recognized in establishing more effective coastal forest
conservation and management, one that reflects local
residents' views and perceptions, and the characteristics ofthe target region.
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