Among the threats that jeopardize conservation efforts in forest ecosystems, fire has become one of the most important. Chiapas represents an informative case study as it displays the same structural fire causes common to other tropical areas: presence of fire spreading from farming sites, fragmented landscapes and a high sensitivity of fuels to ENSO-driven droughts. Since 1984, one million hectares have burned in the state of Chiapas, with peaks recorded in the ENSO events in 1986-1987, 1997-1998 and 2003. Chiapas ecosystems include fire-adapted communities such as pine stands and subdeciduous forests, as well as fire-sensitive ecosystems such as evergreen rainforests and montane cloud forests, which are both suffering from an excess of fire. While fire-adapted ecosystems have higher fire incidence and larger burned areas under normal climatic conditions (i.e. non-ENSO), the presence of ENSO droughts alters this pattern, resulting in higher burned areas in fire-sensitive ecosystems (e.g. montane cloud forests of Chimalapas, evergreen broadleaved ecosystems of the Lacandon and El Ocote). This partly relates to the presence of continuous fuel layers in such systems. Even though the nat ural fire regimes of these different ecosystems are still to be defined, the current fire situation in Chiapas has reshaped fire regimes throughout the state, reducing the intervals without fire and jeopardizing the stability of highly diverse and valuable ecosystems. A particular issue of concern relates to the presence of fire in protected areas. Results suggest that protected areas are not being effective in mitigating fire impacts within their boundaries, and peaks of burned area are common inside parks in years of severe conditions (e.g. 50% of the total burned area in 2003 occurred within El Ocote Biosphere Reserve). Accumulated fuel loads from previous fire disturbances, severe climatic conditions and strong human pressures currently combine to degrade some of the last remaining well-preserved areas in the state. Conservation alternatives and compensations are urgently required in this highly populated region, with decreased use of fire, fire management programmes, fuel treatment, environmental education and economic incentives among the key aspects to consider. © CAB International 2007.
|Title of host publication||Biodiversity Loss and Conservation in Fragmented Forest Landscapes: The Forests of Montane Mexico and Temperate South America|
|Number of pages||23|
|Publication status||Published - 30 Oct 2007|