Ecological response to surface fires: insights from four plant communities in the eastern foothills of the Little Ararat Mountains

Document Type : Complete scientific research article

Authors

1 Phd Student ,Department of forest sciences, Faculty of Natural Resources and Earth Science, Shahrekord University, Shahrekord, I. R. Iran.

2 Associate Professorو Department of forest sciences, Faculty of Natural Resources and Earth Science, Shahrekord University, Shahrekord, Iran.

3 Associate Professorو Department of forest sciences, Faculty of Natural Resources and Earth Science, Shahrekord University, Shahrekord, I. R. Iran.

Abstract

Background and objectives
The majority of fires in Iran's natural areas are anthropogenic, frequently initiated deliberately prior to the rainy season or during periods of peak heat to diminish above-ground biomass and alter land use. Different ecosystems exhibit varying responses to surface fires based on their plant structures. The present study investigates the ecological resistance and resilience behavior against surface fire in four plant communities of shrubland and forest, which are located along an elevational gradient. Furthermore, this research aims to elucidate how grazing, as a disturbance factor, impacts the response of these communities to surface fire.
Materials and methods
Focusing on four plant communities with the type species of: Calligonum crinitum, Rhamnus pallasii, Prunus lycioides, and Juniperus excelsa, the study was conducted from 2009 to 2022 in the east of Little Ararat Mountains foothills. These communities were situated along an elevation gradient ranging from 800 to 1900 meters. Each community was divided into two zones, designated as grazed and grazing excluded. Two categories of surface fire occurrences were identified: sites experiencing a single fire event and those with at least two fire events during the study period. Ecological resistance was quantified by comparing vegetation cover before and after the fire, while ecological resilience was assessed by evaluating the rate of recovery towards pre-fire vegetation cover in subsequent years. A general linear model was used to assess the effects of community, disturbances (fire and grazing), and fire frequency. Principal component analysis (PCA) was employed to analyze the relationships among vegetation cover, resistance, resilience, and precipitation.
Results
Calligonum stood out as the community with the lowest resistance but the highest resilience compared to the other study areas. The communities exhibited a distinct gradient in both resistance and resilience that closely aligned with their respective elevations, with the high-altitude Juniperus community at one end of the spectrum and the low-lying Calligonum at the other. The protection status of the lands did not emerge as a significant factor influencing the ecological resistance. However, it did play a key role in determining their resilience levels, with protected areas generally exhibiting greater resilience than their unprotected counterparts, except in the case of the Rhamnus community. The analysis further reveals subtle responses to the frequency of surface fire events: Ecological resistance did not differ significantly between communities that experienced a single fire versus those that were impacted twice, with the notable exceptions of Juniperus and Prunus, which displayed reduced resistance following the second fire. In terms of resilience, a significant decline was observed in the Rhamnus and Prunus communities after the second fire, while the other two communities were able to maintain their resilience levels. Spatial mapping of the fire-affected locations showed a concerning result, with the majority of sampled points situated far from the full recovery isoline, indicating a general lack of ecological sustainability across the study area. Some points within the Prunus and Juniperus communities were found to be closer to this benchmark, suggesting enhanced ecological stability within these communities. In PCA Calligonum emerged as closely associated with resilience, Juniperus with resistance, Rhamnus with vegetation cover, and Prunus with a combination of cover and resistance.
Conclusion
Resilience-enhancing practices like moderate grazing exclusion can improve stability in most communities, but a comprehensive fire management strategy is needed accounting for the distinct fire response patterns across this elevation/vegetation gradient. The Prunus community exhibited the highest overall sustainability, suggesting its suitability for fire-prone environments. Allowing repeated fires can seriously impair long-term resistance and resilience, emphasizing the need for carefully planned fire management.

Keywords

Main Subjects


  1. 1.Bond, W. J., & van Wilgen, B. W. (2012). Fire and Plants. Springer Science & Business Media, London.

    2.Mirdeilami, T., Shataee, S., & Kavoosi, M. R. (2015). Forest fire risk zone mapping in the Golestan national park using regression logistic method. J. of Wood and Forest Science and Technology. 22, 1-16.

    3.Karimi, S., & Pourbabaei, H. (2017). The effect of fire on structure and regeneration of woody species in the central Zagros forests ecosystem, case study: Bazazkhaneh strait forest area in Kermanshah province. Forest and Range Protection Research. 14, 122-135.

    4.Gholamrezaei, A., Khosravi, M., & Pourreza, M. (2023). The Relationship between wildfire areas and physiographic features in the central Zagros vegetation area, Kermanshah province. Ecology of Iranian Forest. 10, 183-192.

    5.Nazarporfard, K., Babaeipour, H., Salehi, A., & Pilehvar, B. (2020). Effects of fire in different time periods on the composition and diversity of soil seed banks in Lorestan oak forests. Iranian J. of Forest. 12, 61-73.

    6.Azizi, L., Bazgir, M., Balou, M.M., & Heidari, M.M. (2018). Wildfire impact and forest and pasture land use on soil mesofauna community in Badreh-Ilam. J. of Soil Biology. 6, 83-92.

    7.Alizadeh Aliabadi, A., & Siahmansour, R. (2023). An analysis of the fires in forests and pastures in Iran. Goals, consequences, and ways of prevention. Iranian J. of Forest and Range Protection Research. 20, 283-288.

    8.Wang, W., Zhao, F., Wang, Y., Huang, X., & Ye, J. (2023). Seasonal differences in the spatial patterns of wildfire drivers and susceptibility in the southwest mountains of China. Science of The Total Environment. 869, 161782.

    9.Agbeshie, A. A., Abugre, S., Atta-Darkwa, T., & Awuah, R. (2022). A review of the effects of forest fire on soil properties. J. of Forestry Research. 33, 1419-1441.

    1. Azizi, M., Khosravi, M., & Pourreza, M. (2020). Frequency of fire incidence in relation to Zagros forests and rangelands physiography (Kermanshah Province) using MODIS Active Fire Data. Iranian J. of Forest and Range Protection Research, 18, 42-55.
    2. DeRose, R. J., & Long, J. N. (2014). Resistance and resilience: A conceptual framework for silviculture. Forest Science. 60, 1205-1212.
    3. Nimmo, D. G., Mac Nally, R., Cunningham, S. C., Haslem, A., & Bennett, A. F. (2015). Vive la résistance: reviving resistance for 21st century conservation. Trends in Ecology & Evolution. 30, 516-523.Bond, W., & Keeley, J. (2005).
      Fire as a global ‘herbivore’: the ecology and evolution of flammable ecosystems. Trends in Ecology & Evolution. 20, 387-394.
    4. Brooks, M. L., & Matchett, J. R. (2006). Spatial and temporal patterns of wildfires in the Mojave Desert, 1980–2004. J. of Arid Environments. 67, 148-164.
    5. Bowman, D. M. J. S., Balch, J. K., Artaxo, P., Bond, W. J., Carlson, J. M., Cochrane, M. A., D’Antonio, C. M., DeFries, R. S., Doyle, J. C., Harrison, S. P. et al. (2009). Fire in the earth system. Science. 324, 481-484.
    6. Omidipour, R., Ebrahimi, A., Tahmasebi, P., & Faramarzi, M. (2020). Grazing effects on the relationship between vegetation canopy cover and above-ground phytomass with vegetation indices in Sabzekouh region, Chaharmhal va Bakhtiari. J. of Range and Watershed Management (Iranian J. of Natural Resources). 73, 33-47.
    7. Mohammadian, A., Asadi Borujeni, E., Ebrahimi, A., Tahmasebi, P., & Naghipour, A. (2019). The combined effect of fire period and grazing intensity on plant species diversity indices in the semi-steppe rangeland of Chaharmahal and Bakhtiari province. Iranian J. of Range and Desert Research. 27, 84-97.
    8. Naghipour, A., Nabizadeh, S., & Pourrezaei, J. (2019). Effects of fire on vegetation dynamics in semi-steppe rangelands (Case study: Buin va Miandasht rangelands, Isfahan province). Iranian J. of Range and Desert Research. 26, 587-598.
    9. Anderies, J. M., Janssen, M. A., & Walker, B. H. (2002). Grazing Management, Resilience, and the Dynamics of a Fire-driven Rangeland System. Ecosystems. 5, 23-44.
    10. Eftekhari, A., Goudarzi, M., Ashouri, P., & Khalifehzadeh, R. (2019). Changes in vegetation cover of Sirachal mountain rangelands due to fire. Iranian J. of Range and Desert Research. 26, 352-366.
    11. Banihashemi, E., & Naghipour, A. (2020). Variation of plant functional groups in relation to fire in semi-steppe rangelands of Chaharmahal Va Bakhtiari province. J. of Environmental Sciences and Technology. 22, 99-110.
    12. Iran Meteorological Organization. W.A.P.M.D., Partly available online at http://www.azmet.ir/. (2024).
    13. Orwin, K. H., & Wardle, D. A. (2004). New indices for quantifying the resistance and resilience of soil biota to exogenous disturbances. Soil Biology and Biochemistry. 36, 1907-1912.
    14. Cantarello, E., Newton, A. C., Martin, P. A., Evans, P. M., Gosal, A., & Lucash, M. S. (2017). Quantifying resilience of multiple ecosystem services and biodiversity in a temperate forest landscape. Ecology and Evolution. 7, 9661-9675.
    15. Stephan, K., Miller, M., & Dickinson, M. B. (2010). First-order fire effects on herbs and shrubs: Present knowledge and process modeling needs. Fire Ecology. 6, 95-114.
    16. Vilà, M., Lloret, F., Ogheri, E., & Terradas, J. (2001). Positive fire-grass feedback in Mediterranean Basin Woodlands. Forest Ecology and Management. 147, 3-14.
    17. Davies, K. W., Rios, R. C., Bates, J. D., Johnson, D. D., Kerby, J., & Boyd, C. S. (2019). To burn or not to burn: Comparing reintroducing fire with cutting an encroaching conifer for conservation of an imperiled shrub-steppe. Ecology and Evolution. 9, 9137-9148.
    18. Holden, Z., & Jolly, W. (2011). Modeling topographic influences on fuel moisture and fire danger in complex terrain to improve wildland fire management decision support. Forest Ecology and Management. 262, 2133-2141.
    19. Floyd, M. L., Romme, W. H., & Hanna, D. D. (2000). Fire history and vegetation pattern in Mesa Verde national park, Colorado, USA. Ecological Applications. 10, 1666-1680.
    20. Zackrisson, O. (1977). Influence of forest fires on the North Swedish boreal forest. Oikos. 29, 22-32.
    21. Neffati, M., & Louhaichi, M. (2015). Managing rangelands: promoting sustainable native shrub species "Calligonum comosum: the multipurpose sand dune stabilizer".
    22. Bahalkeh, K., Abedi, M., Dianati tilaki, G. A., & Michalet, R. (2021). Fire slightly decreases in the short term the competitive effects of a thorny cushion shrub in a semi‐arid mountain steppe. Applied Vegetation Science. 24p.
    23. Rafiee, F., Jankju, M., & Ejtehadi, H. (2015). Investigation on tolerant, adapted, and sensitive plant traits to chronological wildfires in semiarid rangeland. Iranian J. of Range and Desert Research. 22, 73-85.
    24. Sharifi, J., & Imani, A. A. (2006). An evaluation of the effect of controlled firing on plant cover change and variety composition in semi-steppe rangelands of Ardebil province (case study: Khalkhal preserved research rangeland). Iranian J. of Natural Resources. 59, 517-526.
    25. Bowd, E. J., McBurney, L., & Lindenmayer, D. B. (2021). Temporal patterns of vegetation recovery after wildfire in two obligate seeder ash forests. Forest Ecology and Management. 496, 119409.
    26. Easdale, M. H., Fariña, C., Hara, S., Pérez León, N., Umaña, F., Tittonell, P., & Bruzzone, O. (2019). Trend-cycles of vegetation dynamics as a tool for land degradation assessment and monitoring. Ecological Indicators. 107, 105545.
    27. Qian, C., Qiang, H., Wang, F. & Li, M. (2021). Optimization of rocky desertification classification model based on vegetation type and seasonal characteristics. Remote Sensing. 13, 2935.