**3.2 Cluster analysis**

As described in section 2.3.2, cluster analysis operates in successive stages of fusions, based on the calculation of similarity coefficients. The final structure of the grouping is determined by the desired number of clusters, or by a previously fixed level of similarity that is considered as "acceptable". There is no general rule for the minimal similarity level. In order to make the results comparable with a previous similar study implemented in Indonesia (Purnomo et al., 2005), 80 % of similarity are specified here as acceptable. For instance, the pairs of clusters (12, 13), (7, 12), (10, 11), (7, 10) and (1, 3) show 100 % similarity (Tab. 4),

Setting Up Locally Appropriate Ecological Criteria and Indicators to

Cluster Combined

Stage

Evaluate Sustainable Forest Management in Dinh Hoa District (Northern Vietnam) 213

**Agglomeration Schedule**

1 12 13 1,000 0 0 2 2 7 12 1,000 0 1 4 3 10 11 1,000 0 0 4 4 7 10 1,000 2 3 6 5 1 3 1,000 0 0 9 6 7 14 0,963 4 0 7 7 6 7 0,957 0 6 10 8 4 9 0,926 0 0 11 9 1 2 0,926 5 0 14 10 6 15 0,915 7 0 12 11 4 5 0,889 8 0 12 12 4 6 0,873 11 10 13 13 4 8 0,791 12 0 14 14 1 4 0,479 9 13 0 Table 4. Cluster analysis using group average linkage. Cluster 1 and Cluster 2 (under cluster combined) display the membership of the stakeholders (3 workshops and 12 villages)

Stage Cluster First Appears Next Stage Cluster 1 Cluster 2 Cluster 1 Cluster 2

Coefficients

towards the cluster. The bold line represents the 80% similarity threshold.

Fig. 6. Cluster Dendrogram of stakeholder perceptions. The red line represents the 80 % similarity threshold, delimitating three meaningful clusters in green. The numbers at the end of each cluster arm represent the concerning stakeholder: 1, 2, 3 = expert workshops; 4, 5, 6, 7 =

protection forest, 8, 9, 10, 11 = special use forest and 12, 13, 14, 15 = production forest.


**Principle 2 : Socio-economic & cultural benefits are linked to ecosystem integrity or are of prime importance**

Table 3. b. Final Indicator selection. Principle 2: Socio-economic & cultural benefits are linked to ecosystem integrity or are of prime importance.

meaning the valuation of the indicators were similar for these groups of stakeholders. Moreover, about 93 % of the stakeholders (14 out of 15) display at least 80 % similarity (i.e. all stakeholders excepted number 8).

The 80 % threshold can be used to calculate the final number of clusters from the Agglomeration Schedule Table (Tab. 4) (Janssen and Laatz, 2010; Manning et al., 2008):

$$\begin{array}{rcl} \text{Number of clusters} = \text{Number of subjects} - \text{Value of the last stage over 80\% similarity} \\ = \text{ > 15-12 = 3 clusters} \end{array}$$

This makes it possible to draw a line across the dendrogram to specify the final grouping which is considered as meaningful with a fixed minimum level of 80 % similarity (Fig. 6). According to this final partitioning, 3 clusters were considered as reasonable:

1. The cluster (1, 2, 3) containing the three expert workshops;

2. the cluster containing all villages except village number 8; and

3. village number 8 alone, corresponding to the special use forest village Ban Bac 4.

The subgroups in cluster 1 and 2 are based on minimal differences (similarity between 87 and 100 %), showing a strong homogeneity in the stakeholder's perceptions. Noteworthy, the cluster formation is detached of the forest use types, all forest types appear in all subclusters (Fig. 6).

**Workshops** 

2.1.1 Maintain the forest landscape 100 100 75 75 Y

2.1.3 Presence of corridors 100 75 50 100 Y

destruction 100 0 0 0 **<sup>N</sup>**

functions 67 0 0 0 **<sup>N</sup>**

animals/plants 100 100 100 100 Y

species 100 100 75 100 Y

rare/commercial species 100 0 0 0 **<sup>N</sup>**

genetic diversity conservation 100 0 0 0 **<sup>N</sup>**

2.3.3 All phenotypes are preserved 100 0 0 0 **N**  2.3.4 Gene flow is maintained 100 0 0 0 **N**  2.3.5 Mating system doesn't change 100 0 0 0 **N** 

Table 3. b. Final Indicator selection. Principle 2: Socio-economic & cultural benefits are

meaning the valuation of the indicators were similar for these groups of stakeholders. Moreover, about 93 % of the stakeholders (14 out of 15) display at least 80 % similarity (i.e.

The 80 % threshold can be used to calculate the final number of clusters from the Agglomeration Schedule Table (Tab. 4) (Janssen and Laatz, 2010; Manning et al., 2008):

*Number of clusters = Number of subjects – Value of the last stage over 80% similarity => 15-12 = 3 clusters*  This makes it possible to draw a line across the dendrogram to specify the final grouping which is considered as meaningful with a fixed minimum level of 80 % similarity (Fig. 6).

According to this final partitioning, 3 clusters were considered as reasonable:

3. village number 8 alone, corresponding to the special use forest village Ban Bac 4.

The subgroups in cluster 1 and 2 are based on minimal differences (similarity between 87 and 100 %), showing a strong homogeneity in the stakeholder's perceptions. Noteworthy, the cluster formation is detached of the forest use types, all forest types appear in all sub-

1. The cluster (1, 2, 3) containing the three expert workshops; 2. the cluster containing all villages except village number 8; and

**Protection Forest** 

**Special use Forest** 

100 0 0 0 **N** 

**Acceptance % of agreement on the acceptance of (Yes/No) concerned indicators** 

**Production** 

**Forest Indicator** 

**Principle 2 : Socio-economic & cultural benefits are linked to ecosystem integrity or are of prime importance**

**Criterion Indicator** 

2.1.2 No human habitat diversity

2.2.1 Preserve species with key

2.2.2 Preserve species diversity of

structures

all stakeholders excepted number 8).

2.2.3 Population sizes and demographic

2.2.4 Protection of rare/endangered

2.3.1 Genetic diversity is preserved in

2.3.2 Implementation of measures for

linked to ecosystem integrity or are of prime importance.

2.1 Forest ecosystem diversity

2.2 Forest species diversity

2.3 Forest genetic diversity

clusters (Fig. 6).


Table 4. Cluster analysis using group average linkage. Cluster 1 and Cluster 2 (under cluster combined) display the membership of the stakeholders (3 workshops and 12 villages) towards the cluster. The bold line represents the 80% similarity threshold.

Fig. 6. Cluster Dendrogram of stakeholder perceptions. The red line represents the 80 % similarity threshold, delimitating three meaningful clusters in green. The numbers at the end of each cluster arm represent the concerning stakeholder: 1, 2, 3 = expert workshops; 4, 5, 6, 7 = protection forest, 8, 9, 10, 11 = special use forest and 12, 13, 14, 15 = production forest.

Setting Up Locally Appropriate Ecological Criteria and Indicators to

**4.2 Perceptions among local communities** 

hardly adaptable to the addition of new topics.

communities the perceptions were relatively uniform.

change forest management practices if necessary.

**5. Conclusion** 

conservation and recognition of TEK and reduce hierarchical conflicts.

influencing the correct implementation of PRA and the resulting lists.

**4.3 Pertinence of Multi-Criteria Decision Making (MCDM) for top-down approaches**  MCDM has been identified in previous studies to be a pertinent method to use with experts (Mendoza and Prabhu, 2000b; Mendoza and Prabhu, 2000a; Andrada II and Calderon, 2008; Gomontean et al., 2008). It can save time to begin from a generic set and to modify it afterwards with local experts instead of generating new lists of indicators from scratch. MCDM is a method which easily helps to reach an agreement among all participants. The fact that in this study nearly no indicators were modified from the existent generic set could be explained in two ways. The first could be that the generic template, already resulting from several international processes and expert consultations, covered all requirements of the workshop members. Anyway, ecological elements have often been those where the most agreement appeared among stakeholders worldwide (Purnomo et al., 2005; Sherry et al., 2005). The second explanation could be that the method does not allow easy modifications of the generic template, for the following reasons. Providing a generic set resulting from several international consultations may make local experts hesitant to freely reject / modify elements. Moreover, even if MCDM allows the elimination of elements, the method is

This study reveals that local and expert perceptions differ in their perceptions of ecological sustainability of forest management. However, among experts and among local

It can thus be recommended to combine expert consultations to ensure the scientific validity with local perceptions to ensure the recognition of local values and perceptions. To use only one of the two approaches may reduce the acceptance of the representativeness of the resulting set, leading to conflicts causing difficulties of implementation, and finally to

Evaluate Sustainable Forest Management in Dinh Hoa District (Northern Vietnam) 215

facilitate their implementation and the acceptance of the results, they can contribute to the

Local populations of the villages where PRA was implemented had almost the same perceptions of ecological sustainability of forest management as shown in section 4.0 and there were no measurable differences resulting from the forest use type the villagers were managing. The existing discrepancy of one indicator (Tab. 3a and 3b) dealt with the significance of forests for protecting or mitigating soil degradation. Villages surrounded by protection forests never experienced landslides or soil degradation, ergo could not make the link between the presence of forests and the absence of soil degradation. This does not mean that the indicator is not applicable; it even makes it a suitable element, showing that protection forests actually really protect the soil. It can thus be discussed if future research has to consider forest use types as a meaningful subdivision in the sampling design or not. The village Ban Bac 4, representing the outlier in all data analyses, was the village with the smallest forested area (10 ha), entirely young *Acacia spp.* plantations planted in 2006 and decimated by a disease in 2008. The government did not support new plantations since then, resulting in a general disinterest in forests. Therefore, forest area could be a key element
