4.2 Methods
5.1.4 Conceptual Framework
In this study, I estimate the PPF for the extent of reforestation (as an indicator of a broad range of ecosystem services, as well as a policy goal in its own right) and biodiversity (Shannon-Wiener diversity of tree species)113. Below I provide a conceptual illustration of the PPF (Figure 5.1) where each bundle of goods along the frontier is Pareto efficient (Baumol and Oates 1988; Lockwood 2008). In Figure 5.1a, the opportunity cost in area planted (y- axis) is relatively small when only a few species are added, but increases substantially when many more are added (x-axis). In other words, the quantity of one good (forest cover / extent) cannot be increased without decreasing the quantity of the other (number of tree species). Moving along the PPF from a point closer to the x- or y-axis to a point further away entails relatively low opportunity cost in terms of the good foregone.
113 The Shannon-Wiener H is a widely used index that takes into account the number of species and the relative
numbers of each (Magurran 2004). Spellerberg and Fedor (2003) suggest that species richness be used to refer to the number of species in a given sample, and that ‘species diversity’ is retained given that it is “an expression or index of some relation between number of species and number of individuals” (p. 178). As a widely used and understood index, I used Shannon-Wiener as a measure that captures both species diversity and evenness for illustrative, noting that the same approach could be repeated with other measures of diversity.
Figure 5.1. (a) Example PPF diagram showing gradually increasing opportunity costs in hectares of trees planted as more species are added; (b) Example PPF showing strong heterogeneous societal preferences represented by indifference curves (inverted dashed curves), with some stakeholders preferring biomass (near y-axis) and some tree diversity. This diagram is based on Pareto’s optimality theory that are also referred to as Pareto efficiency curves (Lockwood 2008).
In the context of my study, trade-offs may exist for at least three reasons:
1. Monocultures of certain species may grow faster and thus provide a range of ES more efficiently or sooner (e.g. locking up more carbon ha-1 year-1) than diverse natives; 2. Landowners might prefer to plant monocultures of productive, low conservation value
species, therefore these would cost the PES “buyer” less per hectare;
3. Productive species may tend to be planted on different land, or by different types of landowners, than mixed native species.
Ecosystem Services of Lebanese Forests
Lebanon’s forests, comprising approximately 13% (134,876 ha) of the country’s land area (10,452 km2), store around 1.795 million tonnes of above- and below-ground carbon C (Estephan 2010). This equates to approximately 71.88 tC ha-1. While biomass estimates are only available for the main forest types (e.g. stone pine plantations, mixed conifers, broadleaved), per hectare carbon uptake for most native forest species in Lebanon are not available in the published or grey literature (Dalsgaard 2005). Rough estimates can be averaged broadly for forest type given that there is data on pure stone pine, pure cedar, and mixed (broadleaved-conifer) forests (at least 20% conifers), which are presented in Table 5.1.
Chapter 5 Bundling Ecosystem Services
Table 5.1. Estimated biomass (in million tonnes) and carbon (tonnes per hectare) under reforestation options (Dalsgaard 2005)
Reforestation Option Forest type† Total Biomass tC/ha-1
Stone pine plantation (Option A) Conifer 0.185 1.33
Stone pine & cedar (Option B) Mixed conifer 0.143 1.02
Mixed woodlands (Option C) Mixed forest* 0.220 1.58
*Conifer and broadleaved (both evergreen and deciduous)
†Closest associated forest type for which data was available
Given the scarcity of reliable data on carbon and biomass for individual species, and also on rates of growth, these averages do not provide sufficient information for analysing carbon uptake for the three potential forest types. Biomass and carbon estimates must take into account biogeoclimatic (e.g. climate, rainfall, temperature, soil type) and topographical (e.g. slope, aspect) factors (Jandl et al. 2007; Cañellas et al. 2008). They must also consider both sink and source effects from management regimes (e.g. thinning) and forest fires (Río et al. 2008). Moreover, these factors can vary considerably amongst villages within the same region (or even parcels within the same village) despite sharing similar attributes. All of these contribute to difficulties in estimating biomass or carbon uptake for the 11 tree species used in my study, particularly for the mixed species option (details in section 5.2.3 of this chapter).
Relative to tropical or temperate forests, Mediterranean forests are less productive due to climatic constraints (e.g. low precipitation and high temperatures), which can be further exacerbated by climate change and increasing forest fires (Lindner et al. 2010). Although carbon benefits of reforestation in Lebanon are uncertain, they are likely to be low114. Thus re/afforestation in the Mediterranean is unlikely to be cost-effective enough for private carbon markets compared to avoided deforestation or afforestation elsewhere (Caparrós et al. 2011). Nevertheless, it is important to acknowledge that Lebanese forests provide numerous ecosystem services115 such as watershed maintenance, soil conservation, cultural and landscape values. Many government-financed re/afforestation initiatives use area as a proxy for other ecosystem services (e.g. Bennett 2008; Clement et al. 2009; Wynne-Jones 2013a).
114 I discuss these issues within Lebanon in relation to other Mediterranean countries in chapter 6, section 6.4.2. 115 There are also a wide range of economic benefits that Mediterranean forests provide from non-timber forest
In essence, the overall objective of re/afforestation by Lebanese reforestation stakeholders116 is to reach 20% forest cover (or a 7% increase from its current cover) over the next few decades (chapter 1) and this is considered a greater priority than carbon sequestration. This target suggests that the Lebanese government expects several ecosystem services to correlate with forest extent, perhaps including wood and non-wood forest products, as well as habitats for biodiversity, soil and water conservation, and landscape beauty.117.
The focus of this chapter is to explore point 2 above (landowner preferences)118. Assuming
that most landowners would be willing to enrol more land (as a whole) for planting productive forest trees for less money than mixed species offering little private benefits, this would cost PES buyers less money towards reforestation. If buyers are more focused on cost- effectively meeting forest cover targets as their main objective119, we could expect a social optimum on the PPF towards the y-axis (Figure 5.1b). But if buyers were more biodiversity- focused, then efficient outcomes would occur on the PPF near the x-axis with more species planted on fewer hectares.
5.2 Methods
5.2.1 Study Area
The study area for this chapter comprised villages surrounding the Qadisha Valley watershed and villages lying north of the Tannourine Cedar Reserve. This is an important region from both ecological and cultural perspectives, which includes UNESCO World Heritage Sites (Qadisha Valley and Bcharre Cedar Forest) and Nature Reserves (Tannourine and Ehden forests)120. The region is also within three adjacent IPAs (Radford et al. 2011). This area is characteristic of eu-mediterranean (> 1,000 m.a.s.l.) to oro-mediterranean (> 2,000 m.a.s.l.)
116 The Ministry of Agriculture (MOA) and the Ministry of Environment (MOE) as well as NGOs whose work
is closely aligned the government’s reforestation policy, e.g. National Reforestation Plan of the MOE and National Forest Programme of the MOA.
117 As well as acting as a proxy for carbon sequestration, area reforested is also frequently a policy objective in
its own right (including in Lebanon) and may be related to the provision of other ecosystem services.
118 Also to collect some information pertinent to point 3 regarding displacement of agricultural production. 119 While there were no specific ecosystem services officially mentioned by reforestation stakeholders in
achieving a 20% forest cover target, some of them gave me a range of benefits including soil protection, fuelwood and non-timber forest products, cultural and landscape values, and biodiversity (pers. comm. 2011-12, LRI, AFDC, MOA).
Chapter 5 Bundling Ecosystem Services
bioclimatic zones. Average annual precipitation in this region ranges from 850-950 mm, mainly from October to May with the heaviest occurring between December and March (Jomaa 2008). The vegetation types are typical of Mediterranean forest, woodland and scrub communities containing coniferous, deciduous and mixed forest/woodlands (Abi-Saleh and Safi 1988). Forests, woodland and scrub communities in this region are under severe pressure from urbanisation, agricultural expansion, mining (stone and sand quarries) and overgrazing, as well as fires (Darwish et al. 2010a; Sattout and Caligari 2011). Long-term reforestation has been proposed by national stakeholders aimed at connecting the corridor between the Bcharre and Tannourine forests (MOA and LRI, pers. comm. 2012).
5.2.2 Sampling
A total of 32 villages were identified within three adjacent districts (Batroun, Bcharre, and Zghorta-Ehden) and IPAs (LB01, LB09, and LB11). Key informants121 from 29 out of the 32 villages that were contacted helped provide contacts of landowners, which totalled 229 names (Table 5.2). A small number of landowners were also approached opportunistically in the village of Hadchit). Surveys were conducted with 130 landowners122, of whom twenty were part of the pilot study for calibrating the choice experiment design. Of the 110 surveyed using the final experimental design, four were omitted from the sample post hoc as their landholding status was atypical123. The original intention was to survey 150 respondents (see choice experiment design, below) using the final survey, but fieldwork had to be curtailed due to a deterioration in the security situation in Lebanon. The criteria used for eliciting participants for our study were landowners that are the main decision-makers for their holdings, preferably with at least 1 hectare of land. The criterion for landholding size was determined from the results of chapter 3 while our motive for seeking single decision-makers was to ensure that the respondents had the authority to determine the use of the land in question.
121 These included: mayors, representatives from local agricultural cooperatives and NGOs, and representatives
from the Ministry of Agriculture’s Bcharre and Zghorta extension offices. As in Chapter 3, this method of recruiting respondents was necessary given the security situation in the area.
122 Of the 99 landowners for whom contact details were obtained but that we did not succeed in interviewing,
more than 60% were unreachable (e.g. telephone lines no longer in service). The rest that were contacted did not participate due to scheduling conflicts (e.g. weekend residents only), lack of time or interest, as well as inheritance issues.
Table 5.2. Participant recruitment process Villages in sample No. of landowners
(contact list) No. of survey participants District Population Ehden 46 18 Zghorta-Ehden >24,000 Bcharre 34 23 Bcharre 12,001-24,000 Haddath 28 13 Bcharre 2,001-4,000 Hasroun 21 15 Bcharre 4,001-12,000 Bane 15 12 Bcharre <2,001
Bekaa Kafra 15 8 Bcharre 2,001-4,000
Hadchit 9 6 Bcharre 4,001-12,000
Mazraat Beni Saab 9 6 Bcharre <2,000
Blaouza 8 2 Bcharre <2,000
Qnat 8 6 Bcharre 2,001-4,000
Dimane 7 6 Bcharre <2,000
Kfarsghab 7 5 Zghorta-Ehden N/A
Al-Bouhayrat 5 2 Zghorta-Ehden N/A
Ayto 4 1 Zghorta-Ehden <2,000
Aintourine 3 2 Zghorta-Ehden <2,000
Billa 3 2 Bcharre N/A
Serael 3 1 Zghorta-Ehden <2,000
Barhalioun 2 1 Bcharre N/A
Qnaywer 2 1 Bcharre N/A
19 229 130 2