COS 282-5 - Mayan traditional ecological knowledge and wetland restoration in Lake Atitlan, Guatemala

Background/Question/Methods

Littoral vegetation such as tul (local language for both Typha domingensis and Schoenoplectus californicus) of Lake Atitlan is known to provide diverse ecosystem services including removal of nutrients and pollutants, and water oxygenation. It is a habitat for fauna, a nesting site for birds and an oviposition site for fish and snails. The vegetation provides cultural ecosystem services in the form of materials for making sleeping mats, handicrafts and ceremonial ornaments. For human communities, most of whom are Indigenous Maya, they bring a sense of place, personal identity and provide scenic beauty. Despite these numerous benefits, degradation and loss of the tulares has been reported. We used a three-level assessment: first, using remote sensing Sentinel-2 and Google Earth photographs from 2018 to measure the littoral vegetation in four Maya Tz'utujil communities: Santiago Atitlan, San Pedro, San Juan and San Pablo. Second, a wetland stressor assessment including: 1) Land use and land cover analysis, 2) coverage of Hydrilla verticillata, a non-native macrophyte and 3) lake level fluctuations. And third, a plant survey to measure vegetation structure and plant diversity. Interviews and participatory workshops were used to determine how farmers, fishers and artisans consider wetland use, degradation and in turn its restoration.

Results/Conclusions

Traditional cultivation and management in the Santiago and San Juan shores appeared to relate to improved tul conservation compared to villages where no traditional tul cultivation is practiced. Remote sensing showed that the highest tul coverage was in Santiago with 81% of S. californicus and 98% of T. domingensis in the study area; this village had the highest density, height and diameter estimated marginal means, and the highest diversity indices (Jacknife-2 and Shannon index), followed by San Juan. In other villages without traditional cultivation littoral regions were more degraded, with higher coverage of invasive H. verticillata. Other authors have also found that traditional ecological knowledge (TEK) informed land management is often of low disturbance that enhances productivity and biodiversity while obtaining products for cultural uses. Water level comparison from 2018 to 2021 showed 9.3 to 41.5 meters reduction. Interviews and participatory workshops have found various actions of traditional managers to cope with those drivers, however social and economic drivers are equally relevant to inform a more holistic framework for biocultural restoration. Transdisciplinary approaches guided by TEK and informed by ecological and social sciences appear appropriate for restoration planning and design this landscape and others with active systems of TEK.