Local land users in our case study perceive woody species to be more impor-tant than herbaceous species, because they provide palatable biomass in the dry season. These findings correlate with studies published in 1990 (McKell), where underestimated potentials of woody species, mainly shrubs are dis-cussed. These kinds of findings are still not well integrated into ecological re-search about semi-arid rangelands. In range ecology herbaceous species’
abundance is regarded as a key indicator for rangeland condition influencing management decisions. In particular, the abundance of perennial grasses is named as indicative for rangeland condition. If local perception and salience of forage species is not considered, discrepancies to scientific knowledge, and their functional explanation might be missed. Woody species might be used as local indicators for decision-making processes in range management addi-tional to grass species. This might also be important for the success of local monitoring schemes.
2.4.1 What gives salience in local perception?
One of the reasons why woody species are the most important forage species in local perception is that their palatable biomass is available in times of low resource availability. In contrast, herbaceous species biomass is much more driven by the variability of annual rainfall, particularly in arid and semi-arid rangelands. Woody species are salient in local perception because they provide palatable biomass in the dry season and are thus important for livestock herd-ing in scarce times. For our case study we conclude that it is this reliability that gives salience in local perception. These findings also support the basic idea of pastoralists being a highly reliable institution: pastoralists rather search for reliability than escape from risk (Roe et al. 1998). This is achieved by creat-ing a reliable flow of life-sustaincreat-ing goods and services from highly variable rangeland ecosystems.
In this way LEK, about processes or items may help in refining research hy-potheses and give further insights into locally important and unimportant processes and items for researchers, managers and policy makers. For example, by analysing the traditional range management of the Ova-Himba, Müller et al. (2007), detected intra- and inter-annual heterogeneity of resource use through specific resting periods as crucial for a high productivity of biomass in
2.4.2 Implications for the methods
The main limitation of our methodological framework is that it is only as ac-curate as the data that it is based on. Contradictions might arise in the free-listing if plants are more commonly mentioned due to reasons other than their importance as forage species. For example woody species might be more prominent in the informant’s minds for their height rather than their value as a forage source. Another reason for the high occurrence of woody species in local free-lists might be the importance of woody species in other areas of daily life, such as religious uses (Brauer 1925) or fire wood (Eichhorn 2004).
Another option for the differences of local perception and ecological perform-ance might be the relatively small area in which ecological data was collected since it was also found that local perception of important forage species is not restricted to the local grazing area.
In general, the application of the methodology made an in-depth analysis pos-sible. It also confirmed that integrating LEK into scientific research is a valu-able approach because it can complement and strengthen the scientific re-search with data on local valuation of certain ecological items, e.g. plant spe-cies and entities. This provides important aspects of local environmental per-ception by identifying preferences, and gaining new insights into local deci-sion-making processes regarding natural resource use.
Apart from maintaining biological productivity and natural resource conserva-tion, social acceptability is also regarded as an important principle for the sus-tainability of natural resource use in arid and semi-arid ecosystems (Snyman 1998). Consequently, the incorporation of local people’s ecological knowledge and furthermore, their participation and integration into the research process, are key factors for sustainable development and advances the acceptation of innovative management approaches, such as adaptive management strategies (Berkes et al. 2000) or community-based natural resource management (Stuart-Hill et al. 2005).
The framework proposed here can be applied in various other fields of research.
It is particularly interesting for studies on ecological items which supply eco-system services, thus having a direct or indirect economic value. For example, medicinal plants, native food plants, or fish species have a direct economic value as provisioning ecosystem services, while fertile soil types and target spe-cies for conservation have an indirect value. All these ecological items have
been subject to studies on LEK (Brown et al. 2004; Klintenberg et al. 2007; An-gassa and Oba 2008).
The presented framework can identify indicators for changeable conditions, e.g. through the comparison of local perception of changes in ecological per-formance of an item and the assessed ecological perper-formance of an item, e.g.
over-utilization in fishery (Wilson et al. 2006), or for the condition of range-lands. We suggest that there is a role for the application and further develop-ment of this approach in ecological and social-ecological research. We recom-mend the application of the framework to complement ecological research with local ecological knowledge, which can provide important aspects in local natural resource management, biodiversity conservation and ecosystem service provision.