Year : 2015 | Volume
| Issue : 4 | Page : 395-406
Identifying Social-ecological Linkages to Develop a Community Fire Plan in Mexico
Rachel A.S Sheridan1, Peter Z Fulé2, Martha E Lee2, Erik A Nielsen3
1 Current affiliation: US Forest Service International Programs, Washington DC, USA; Research conducted at: College of Engineering, Forestry, and Natural Sciences, School of Forestry, Northern Arizona University, Flagstaff, AZ, USA; United States Peace Corps, Querétaro, Querétaro, Mexico
2 College of Engineering, Forestry, and Natural Sciences, School of Forestry, Northern Arizona University, Flagstaff, AZ, USA
3 College of Engineering, Forestry, and Natural Sciences, School of Earth Sciences and Environmental Sustainability, Northern Arizona University, Flagstaff, AZ, USA
Rachel A.S Sheridan
Current affiliation: US Forest Service International Programs, Washington DC, USA; Research conducted at: College of Engineering, Forestry, and Natural Sciences, School of Forestry, Northern Arizona University, Flagstaff, AZ, USA; United States Peace Corps, Querétaro, Querétaro, Mexico
Source of Support: None, Conflict of Interest: None
|Date of Web Publication||8-Apr-2016|
| Abstract|| |
Community forestry in rural Mexico presents a unique opportunity to study the linkages and feedback within coupled social-ecological systems due to the fact that agrarian or indigenous communities control approximately half of the national territory of Mexico. We used social and ecological diagnostic tools to develop a fire management strategy for a communal forest containing an endemic piñón pine species, Pinus cembroides subs. orizabensis, in the state of Tlaxcala, Mexico. The ecological diagnostic was done through fuel inventory, forest structure sampling, and fire behaviour modelling. The social assessment was conducted through household interviews, community workshops, and direct participant observation. The ecological fire hazard was quantified and coupled with the social assessment to develop a fire management plan. Vertical fuel continuity and flashy surface fuels created a high fire hazard. Modelled fire behaviour showed a rapid rate of spread and high flame lengths under multiple scenarios. Relative impunity for starting forest fires, poor community and inter-agency organisation, and lack of project continuity across organisational sectors appear to be the most significant social limiting factors for wildfire management. Combining both social and ecological diagnostic tools provides a comprehensive understanding of the actual risks to forests, and identifies realistic community-supported options for conservation on cooperatively managed lands.
Keywords: social-ecological systems, community forestry, common-pool resource theory, wildfire management, Mexico
|How to cite this article:|
Sheridan RA, Fulé PZ, Lee ME, Nielsen EA. Identifying Social-ecological Linkages to Develop a Community Fire Plan in Mexico. Conservat Soc 2015;13:395-406
| Introduction|| |
Wildfire management within social-ecological systems
Social-ecological systems (SES) are a useful lens to study the linkages and feedbacks between environment and society. Specifically, these systems examine the interactions between bio-physical, socio-political, economic, and cultural components at varying spatial and temporal scales. The interactions of these variables are then used to develop a diagnostic approach to identify which of these variables are relevant for analysing and identifying solutions for these complex social-ecological issues (Ostrom 2007; Lassoie and Sherman 2010). Understanding how humans have managed and are managing an ecosystem is critical for understanding how that ecosystem functions (Lassoie and Sherman 2010). Likewise, bio-physical systems, too, must be understood as they can directly impact livelihoods and social structures. Social-ecological systems help develop a diagnostic approach for analysing the interactions of several multi-tiered variables and provide insight into any feedback loops that might occur between the ecological and the social systems.
Wildfire in communally-governed forests is neither strictly an ecological nor strictly a social issue. On the contrary, it presents both ecological and social dimensions that must be understood and addressed in tandem (Rodríguez 2008). Multi-disciplinary and participatory research provides a richer understanding of the actual challenges related to fire management and forest conservation on communally-managed lands (Redman et al. 2004; Castillo et al. 2005). Using the SES approach, this paper assesses the hazard of severe wildfire in a communally-managed forest in the south-central state of Tlaxcala, Mexico, and identifies community-supported options for wildfire mitigation.
Social-ecological systems within the Mexican context
The reason to combine social and ecological research within the Mexican context is rooted in the land tenure history of Mexico. Rural, and often marginalized communities called ejidos, control an estimated 50– 80% Mexico's forestland (Bray et al. 2005). Ejidos are communal landholdings established under the 1917 Mexican Constitution (Myer et al. 2003). Most ejidos consist of agricultural land that is held in trust by individual ejidatarios (ejido members) and passed on through inheritance. Forests and range-land, in contrast, are typically shared in common by ejidatarios (Sheridan 1988).
Ejidos, including their communal forests, are typically managed by the Comisariado Ejidal (Ejidal commission, comprised of President, Secretary, and Treasurer), and the general assembly, which consists of all ejido members who show up to the meetings to vote. Usually, ejidos have forestry extension agents who help the community implement different conservation projects. The Mexican National Forest Service, CONAFOR, determines the structure and guidelines for implementation for these projects, creating a top-down approach for forest management. The general assembly votes on what government-defined project they want, and then they apply to CONAFOR to receive funding to implement the project.
Ejidatarios often comprise a small percentage of the total population of the ejido (INEGI 2010). The remaining community members are known as avecindados, or the landless community members, who do not have the right to vote on any issue related to ejido lands, including the communal forests. Some avecindados are children of ejidatarios who have the potential to inherit ejido lands, and thus voting rights. Other avecindados, however, have no ties to the ejido, and therefore no hope of becoming ejidatarios or of being able to participate in land management decisions.
The principal difference between ejidatarios and avecindados is lack of voting rights and access to communal lands within the ejidos (CONAFOR pers. comm. 2014). Additionally, while ejidatarios have the legal authority to govern their forests, many ejidos do not have sufficient resources for management. Rather they depend on the government funding for any forest conservation project (CONAFOR pers. comm. 2014). Furthermore, ejidos are institutionally embedded in and legally bound to the Mexican federal system through the Agrarian Law and therefore operate only as semi-autonomous entities that manage their communal forests within several layers of government agencies (Bray et al. 2005).
Managing the communally controlled forests under the ejido tenure system presents several organisational and participatory challenges. SES analysis can help examine these challenges by identifying the relevant variables, such as the different user groups and governance systems, and analysing their effects on the resource to be managed (Ostrom 2007). Global research on common-pool resources (CPR) and community forestry literature specific to Mexico highlight relevant variables that influence how communal resources are managed.
Ostrom (1990), in her seminal work on CPRs, identified a set of principles common to groups who had successfully managed shared resources. In particular, actively monitoring a shared resource and enforcing graduated sanctions against those who break the rules regarding that resource are indicators of a robust CPR management system. Additionally, Sarukhan and Merino Pérez (2007) argue that strengthening local rule and collective action is critical for improved forest management in Mexico. The potential for land tenure problems exists within the ejido system, as a large portion of stakeholders is disenfranchised (the avecindados), and thus, not able to legally participate in CPR management (Ostrom 1990; Agrawal 2005a). If community members feel excluded from the decision-making process or feel as though their views are ignored, they are more likely to reject or ignore conservation plans altogether (Danielson et al. 2007), or sabotage them, as has occurred in community forests in India (Agrawal 2005b). Additionally, the strong federal regulatory framework, under which ejidos operate, can make CPR management more complex, where communities essentially co-manage their resources with the federal government (Bray and Merino Pérez 2002).
Wildfire Management in Ejidos
The SES approach is useful for assessing wildfire hazard and for developing community-supported fire management plans in ejidos. Wildfire management plans can only be successfully implemented when managers have access to reliable data on fuel type and quantity, and when they understand both the socio-economic context of the area to be managed, and the social-ecological interactions that are taking place (Jardél Peláez 2009). Fire plays a complex and insufficiently studied ecological role in Mexican forests, reflecting the extraordinary biological diversity of the country and its varied social contexts (Rodríguez and Fulé 2003). Here we provide details of the studied ecosystem and its fire-related issues. The understanding of hazardous fuels and the ability to identify priority areas is limited in the ejidos and government agencies, because little data collection has been done to characterize or quantify fuel loads in Mexican forests (Jardél Peláez et al. 2010). Measuring and characterizing fuel loads allows for a more robust and reliable understanding of the actual fire hazard and also provides baseline data that can be measured over time to assess the effectiveness of any management or conservation activities therein implemented. Furthermore, forest fires per se may be a symptom of other root problems, because illegal logging, land tenure conflicts, and land-use changes are what cause most forest fires in central Mexico (Rodríguez Trejo 2008). Human activities are an integral force in these forest systems, and the social components should be considered part of the study of ecosystem dynamics (Redman et al. 2004).
The state of Tlaxcala, Mexico, is a relevant area to examine wildfire using the SES approach. The state contains approximately 4,700 ha of piñón pine forest, of which, approximately 20% has been affected by forest fires between 2003 and 2013, the time period of the available data (CONAFOR 2013; RAN 2013). However, this percentage underestimates the actual extent of forest fires. If communities combat wildfires themselves without outside support, these fires are often not recorded by CONAFOR. While small in size (<5 ha), these fires typically have high tree mortality rates (CONAFOR 2013). CONAFOR (2013) estimates that anthropogenic fires account for 98% of all forest fires in Tlaxcala.
Pinus cembroides is listed as an endangered species under Mexican law (SEMARNAT 2010). Pinus cembroides subs. orizabensis is an endemic piñón pine species found only in the Mexican states of Tlaxcala, Puebla, and Veracruz (Bailey and Hawksworth 1992). Segura and Snook (1992) note that this specieshas a high economic, ecological, and social value, but land-use change, pests and pathogens, and severe wildfires pose a significant threat to the continued existence of these forests. What little forest remains has a heavy fuel load, making it susceptible to more catastrophic, stand-replacing fires (Segura and Snook 1992; CONAFOR 2013).
These wildfires also pose a risk to human lives. In March 2012, a forest fire erupted in a piñón stand in eastern Tlaxcala and two men from a nearby community died combating it. At the time of the fire, no community in the region had training or equipment to safely fight forest fires.
Using a social-ecological systems approach, in which we sought to integrate ecological data within a socio-political and institutional context (Berkes and Folke 1998), we assessed the risk of fire in a communally-managed piñón pine forest in eastern Tlaxcala. Regarding the ecological risk we asked: what is the current fuel complex and what are the potential risks and hazards for fire; specifically, what type and how much fuel is present in the forest? For the social assessment we asked: under what socio-political contexts have forest fires been occurring and what are any social or institutional barriers that could impede sound wildfire management? Lastly, we asked: given the social-ecological interactions that are taking place, what management options are available for mitigation? Our overarching objective was to identify any linkages and feedbacks between the ecological and social results to provide a more comprehensive understanding of fire hazard, and to develop a community-supported fire management plan.
| Study Site and Methods|| |
Study site: physical site
The state of Tlaxcala is located in central Mexico, approximately 200 km southeast of Mexico City. The study site is situated in the rural ejido of Santa María Las Cuevas (SMC) (19°23´45”, 97°43´39”) in the eastern portion of the state; SMC contains the largest contiguous tract of P. cembroides subs. orizabensis forest in the state of Tlaxcala (CONAFOR 2012) ([Figure 1]).
|Figure 1: Aerial view of the study site. The yellow points are the forest and fuel inventory plot sites. State of Tlaxcala shown in inset with the municipality of Altzayanca highlighted|
Click here to view
SMC forms part of the Sierra Norte de Puebla mountain range that runs west to east in the zone where two major mountain ranges meet: the Sierra Madre Oriental and the Trans-Volcanic Belt. The communal forest of SMC, which covers 484 ha, has a northwest aspect, an average slope of approximately 25%, and elevation ranging between 2,400– 2,600 m. Soils, regosols, and volcanic parent material are nutrient-poor with low organic content and little capacity for water or nutrient retention (Driessen and Decker 2001; Guerra de la Cruz and Buendía Rodríguez 2010).
The study region is characterized as semi-arid, with a single rainy season that lasts from June through October, with an average annual precipitation of 600– 800 mm. The remaining months of the year (November through May) see minimal rainfall. Annual temperatures range from 5.6°C to 22.3°C; the hottest and windiest months occur between March and May, before the summer rains (Hernández Moreno et al. 2011). The majority of wildfires in Tlaxcala occur between February and May, towards the end of the dry season, when the region experiences its hottest and windiest months. These severe weather conditions increase the likelihood of escaped, human-ignited fires, such as agricultural fires and campfires (CONAFOR 2012).
Temperate forests comprised of piñón pine (Pinus cembroides sub. orizabensis), alligator juniper (Juniperus deppeana), at least three oak species (Quercus spp.), and palma (Nolina parviflora) characterize the higher elevations of SMC´s communal forest; the xerophytic succulents agave (Agave spp.) and prickly pear (Opuntia spp.), as well as palma and juniper, dominate the lowlands (Redzowsky 1978). Piñón and palma species are the two dominant overstorey species. Light, dry, flashy fuels such as grasses and shrubs characterize the understorey.
Study site: community description
SMC has a primarily agrarian-based economy, and is located in the municipality of Altzayanca, one of the poorest municipalities in the state (INEGI 2010). Education levels within the community are low. Approximately 11% of the population over the age of 15 cannot read or write, and approximately 27% of the population over the age of 15 have not finished primary school (up to the 5th grade) (INEGI 2010).
Regarding forest management, in addition to the Comisariado Ejidal and the general assembly, SMC has a voluntary forest vigilancia unit that occasionally patrols the forest for any illegal resource extraction or to detect any wildfires. CONAFOR has implemented several projects within SMC's forest, including reforestation and soil restoration projects, payment for environmental services, and temporary employment projects that typically consist of firebreak construction. The ejido has a management plan for the palma species. They do not, however, have a timber management plan for the piñón species, which limits their ability to carry out fuel reduction activities like pruning and brush removal. SMC employs a forestry extension agent through CONAFOR to help the ejido request and implement these CONAFOR-sponsored conservation projects.
The ejido also eliminated grazing from the communal forest in 2003 in an effort to reduce soil erosion and to qualify for CONAFOR-sponsored conservation projects. Prior to elimination, community members grazed upwards of 1,000 head of cattle, goats, and sheep on the communal forest (community members of SMC pers. comm. 2012).
At the time that this research was carried out, firebreak construction was the only fire management activity that was being implemented in SMC's forest; the occasional patrols carried out by the vigilancia group were the only prevention efforts that existed. In a 2008 report to CONAFOR, community members identified wildfire as its main environmental threat and requested more support, either through fire suppression or management (Zamora Vázquez 2008).
Study site: the many values of piñón in Tlaxcala
Harvesting piñón seeds is potentially one of the most profitable sources of income in this region. On average, a kilogram of piñón seeds sells between 50– 100 pesos (US$4– 8) (Hernández Moreno et al. 2011). Large diameter trees (≥25 cm) can produce over half a kilogram of piñón seed (Dr. Vidal Guerra de la Cruz pers. comm. 2014). However, Hernández Moreno et al. (2011) followed the chain of production of the piñón seed from the harvest in SMC to the marketplace in Puebla and Mexico City and found that 77% of the money earned from selling the seed was made outside of SMC. Due to irregular seed years, lack of regulation, and limited communication and organization within the community, seed collection remains a peripheral economic activity.
P. cembroides forests are often found on hill slopes, with communities located along the foothills or in the valleys below these forests. In the rainy season following wildfires, SMC has experienced significant structural damage due to flooding, including destroyed roads and bridges. In addition to their economic value, P. cembroides forests represent important natural erosion control structures.
Because this species is at the southernmost range of all piñón species and because it is found at the confluence of northern and central mountain ranges, P. cembroides subs. orizabensis exhibits unique genetic qualities as well as potentially adaptive and resilient features, such as the ability to grow in nutrient-poor hardpan soils and the ability to withstand extended periods of drought (Fonseca 2003). Therefore, the Mexican government hopes to use this species more in reforestation efforts, although to date, there have been no specific management plans made for protecting natural P. cembroides forests (CONAFOR Tlaxcala pers. comm. 2013).
Study site: wildfires in SMC
In March 2011, the most significant recorded forest fire in the community occurred, burning approximately 120 ha of 484 ha of SMC's piñón-palma forest. At least four other fires, some small in size, but each with greater than 75% tree mortality have burned in the community since 2003 (when CONAFOR began to record fire size and occurrence); at least two of those fires originated from neighbouring communities in Puebla (CONAFOR 2013).
No published fire history exists for these P. cembroides subs. orizabensis forests. P. cembroides are found in a variety of plant community structures and compositions (Pavek 1999). Rodriguez-Trejo and Fulé (2003) note that P. cembroides have only two of the nine fire traits that would indicate they are adapted to a surface-fire regime. They classified the fire regime for the species as unpredictable and variable by region. In an unpublished report, CONAFOR lists these piñón stands as characterized by infrequent, stand replacing fires (CONAFOR pers. comm. 2014). Even if this subspecies is currently experiencing its natural fire regime of stand-replacing fires, these forests exist in a heavily fragmented landscape; the short time frame in which these fires are occurring suggest that this species is not able to regenerate quickly enough to replace burned stands.
N. parviflora, the codominant overstorey species found alongside P. cembroides in eastern Tlaxcala, is an extremely volatile, but fire resistant species; only the top of the plant burns in a fire and then sprouts from the trunk post-fire (Reyes Bautista 2002).
N. parviflora seeds are also dispersed by wind, which facilitates regeneration especially when compared to the heavier piñón seed that falls near its parent tree, and then experiences heavy predation by rodents and birds (Pavek 1999; Reyes Bautista 2002). Community members noted the rapidity with which N. parviflora catches fire and spreads to the crown. They also commented that the top of the plant will often break off and be launched into the air, increasing the likelihood of spot fires (Community members of SMC pers. comm. 2012).
In sum, eastern Tlaxcala is experiencing serious threats to the continued existence of this endemic, endangered species of piñón pine. The intensity and severity of these wildfires also threaten human life and property. Furthermore, the community specifically identified wildfire as its primary environmental threat, and requested support from CONAFOR to better manage fires. The sheer urgency of trying to preserve this unique landscape, coupled with the complex tenure agreements that dictate management of this region, make this a relevant site to study the social-ecological linkages concerning fire risk in Mexican community forests.
Methods: fuel and forest measurements
Fuel management can significantly mitigate fire risk in forests (Rodriguéz Trejo 2008). Characterizing and quantifying forest fuels allows land managers and communities to make more informed decisions on how to reduce fire hazard in their forests. Knowing that even under careful watch, fires can and do escape, having a fuel management plan can reduce the intensity and severity of those escaped fires (Rodriguéz Trejo 2008).
To measure forest structure and fuels, a team of two university students, one community member, and the senior author, Ms. Sheridan, established 30 fixed-radius plots (radius of 11.28 m = 400 sq. m) on a grid across 90 ha of unburned forest in SMC to measure the forest overstorey (all trees taller than breast height, 1.3 m). We counted N. parviflora as an overstorey species. We recorded species and measured height, crown base height (CBH), and diameter at breast height (DBH). We tallied all trees below breast height by size class (0– 40 cm, 40.1– 80 cm, and 80.1– 1.30 cm). We inspected trees for evidence of pruning (such as cutting dead branches for firewood) and asked community members about fuelwood collection practices.
We took two separate crown base height (CBH) measurements for each overstorey tree because most supported the epiphytic bromeliad, Tillandsia spp., which sometimes reached the ground, and nearly all of the bases of N. parviflora were covered in dead fronds that could serve to carry fire. For each overstorey tree, we took a live CBH measurement (distance from the ground to the first live branch) and a dead CBH measurement (distance from the ground to first dead palm frond or to first epiphytic plant found).
We installed nested subplots (5.64 m radius = 100 sq. m) in each of the larger plots and tallied all shrubs and cactus below breast height (1.3 m) by size class (0-40 cm, 40.1-80 cm, and 80.1-1.30 cm). Dead woody biomass and forest floor depth were measured using two, 15 m planar transects (Brown 1974). We measured canopy cover by vertical projection and understorey cover at 2 m intervals, along four 16 m transects. At each point, we recorded canopy (yes/no) and understorey cover by height and by life form (shrub, grass, or forbs).
Fire behaviour predictions under the current climate were modelled using high, moderate, and low dead fuel moisture content (for dead fuel moisture contents used, refer to Scott and Burgan 2005) in the fire behaviour simulation model, BEHAVE. Based upon the fire weather conditions, surface and canopy fuel loads, and topography (aspect, slope), we computed numerous fire behaviour characteristics including rate of spread and flame length, which measure the forest's vulnerability to severe wildfire. Experienced fire managers reviewed the model outputs to ensure that they were logical and consistent with observed fire behaviour. Local firefighters who combated the 2011 SMC fire described the weather conditions during the fire as they remembered them (CONAFOR did not have weather kits to take meteorological readings during the fire). We used the Grass-Shrub Model 4 (GS-4), which is characterized as, “heavy grass/shrub load, depth greater than two feet. Spread rate high, flame length very high” (Scott and Burgan 2005).
Methods: social assessment
The goal of the social assessment was to identify any social or institutional barriers to wildfire management and to establish community-supported management options. We used an embedded, mixed-method approach that included household surveys, workshops, an oral history interview, and direct participant observation. With the embedded design, a secondary data set provides a supportive or complementary role to the primary data set (Creswell et al. 2003). Specifically, the qualitative data from the workshops, the oral history interviews, and direct participant observations were coded according to theme, and then synthesized and embedded within the quantitative data set derived from the household interviews as a way to supplement and reinforce the statistical results.
The household interviews were conducted between July 2012 and February 2013 by the senior author. There were approximately 150 occupied households in SMC. We defined a household as people living in the same compound or sharing the same agricultural fields. We used a GoogleEarth image of SMC to outline and number each compound. Using the aerial image and ground truthing a subset of 20% of the compounds, we conducted a random sample of all households in SMC using a 90% confidence level for a total sample size of 101 households.
The household survey included a 12-page questionnaire, which was designed using the SES approach and variables that could affect wildfire management within ejido systems (Ostrom 2007; Sarukhan and Merino 2007). Questions included household size, education levels, occupation, and hectares of cultivated land. The survey also included questions that focused specifically on SES variables, such as land tenure agreements, how the commons are managed and how they should be managed, community organisation, sanctioning capabilities, government-community relations, perceived environmental threats, and fire management options.
To identify community-supported options for wildfire management, we hosted a series of workshops that employed community participation diagnostic tools, such as community mapping exercises by gender, natural resource ranking activities, and group interviews (Chambers 1994). Participation rates ranged from eight to forty people per workshop. In the final workshop, we presented the preliminary results of both the ecological and social studies, and worked in small groups to develop community-supported options for a fuel management plan. We also conducted a group oral history interview with eight older community members to document changes in forest management over time and to provide insight, specifically into how fire was perceived and managed, given that no thorough fire history data for the region exists prior to 2003 (CONAFOR 2012). The extension agents, CONAFOR, and community leaders helped organize and direct these workshops.
The senior author lived in the community part-time for eighteen months where she participated in several community development and conservation projects. She kept a journal for reflecting on day-to-day interactions and impressions relevant to this project.
For the household surveys, we recorded the respondent's gender, land tenure status, and age. Of the 101 households interviewed, 19 interviewees were ejidatarios (=male landowners), three were ejidatarias (female landowners), six were avecindados (=landless males), 25 were avecindadas (landless females), 29 were females who had a family member who was an ejidatario/a, and eight were males who had a family member who was an ejidatario/a. In some instances, both the husband and wife were interviewed together; we interviewed four couples where at least one of them was an ejidatario/a, two couples where at least one family member as an ejidatario/a, and two couples where both husband and wife were avecindados/as. Three men interviewed were small landowners with no ejido voting rights.
Given that local rule is important to managing shared resources (Ostrom 1990; Danielsen et al. 2007), we wanted to see whether avecindados, an essentially disenfranchised group in the ejido system, had differing views on the ejido governance system and forest conservation as compared to ejidatarios. In the interviews, we asked participants to rank seven groups of people or organisations/agencies (e.g., ejidatarios, avecindados, state/federal government, ejido general assembly, and others), as to whom they thought had the most power in forest management decisions. They were then asked to rank the same seven options in the order that they would ideally like to have the community structured. We first tested for differences in responses between gender for both avecindados/as and ejidatarios/as using a student's t-test (p-value <.05). We used the Mann-Whitney U to test for differences in the ranking of each group of people or organisations/agencies in the current versus the ideal power structures. As a way to test whether land tenure status effects one's desire to protect communal lands, we used a chi-square to test for differences in ejidatario/a versus avecindado/a respondents' willingness to contribute financially to protect the community's forest.
To better understand the perceived effectiveness of the federal government in ejido land management, interviewees were asked whether they thought CONAFOR projects have helped, hurt, or had no effect on the forest. We used a student's t test to see if there were any response differences between ejidatarios and avecindados. Interviewees answered several open-ended and yes/no questions on community organisation, and the community's ability to implement sanctions against people who broke laws related to their forest. Lastly, in both the interviews and workshops, we asked participants how they would like to manage their communal forest, especially relating to fire management. For example, in the interviews, participants were asked whether or not (yes/no) they were in favour of different fuel management options. In the workshops, participants were asked to list what management options they would like to implement on their landscape.
Results from the social analysis are presented according to themes that arose from the household survey. Open-ended and qualitative data from the household survey were coded numerically according to common themes that arose throughout the interviews, and statistical analysis was conducted using Microsoft Excel. Workshop, oral history, and direct participation results are reported alongside the survey data as supplementary information. The ecological risk of fire was then coupled with the social assessment to develop a set of community-supported management options that would reduce the risk of fires in these shared forests. Community participation was emphasized in the development of these management solutions in interviews and workshops, as participants helped determine which fire management options would or would not be implemented.
| Results|| |
Overstorey structure and canopy fuel complex
At least four overstorey species were found in all plots: Juniperus deppeana, Pinus cembroides subs. orizabensis, one or more Quercus spp., and Nolina parviflora. Pinus teocote was found in one of the higher elevation plots. P. cembroides subs. orizabensis and N. parviflora were the dominant overstorey species with mean densities of 467 and 448 trees per hectare (TPH), respectively ([Table 1]).
Canopy fuels were characterized by extensive fuel ladders, as shown by absolute measurements of crown base height (CBH), as well as the ratio of CBH to total tree height (TH), expressed as a percentage ([Table 1]). This measurement provides an indication of the likelihood of fires moving vertically up to the canopy in the stand. The juniper and oak species had the lowest CBH:TH percentage, meaning that the mean first live branch was closer to the ground. Most of the piñón trees showed signs of pruning, which is probably why they have a higher percentage. The live CBH to TH ratio ranged from 18– 49%. However, the fact that many trees had a large amount of dead branches or fronds near the ground was reflected in the much lower dead CBH to TH percentage (3.12– 19.55). This difference showed that there was continuous light, dry fuel near the surface, creating uninterrupted ladder fuels to the canopy. The mean canopy cover percentage was 64.38%.
Surface fuel complex and BEHAVE analysis
Biomass of both, fine woody debris and coarse woody debris (1-hour to 1,000-hour), was low. Mean litter and duff depth were 1.8 cm and 1.6 cm, respectively. One-hour fuel loads averaged.25 Mg/ha, 10-hour fuels averaged.19 Mg/ha, and 100-hour fuels averaged.10 Mg/ha. 1,000-hour sound and 1,000-hour rotten fuels had a mean fuel loading of 5.6 Mg/ha and1.1 Mg/ha, respectively. Grasses covered an average of 49% of the surface area of plots. Shrub cover was 17%, and forb cover was 12%.
The BEHAVE model outputs, which simulate fire behaviour under current climate conditions, showed a rapid rate of spread (RoS) and high flame lengths (FL) at all three dead fuel moisture levels. In the high dead fuel moisture scenario the RoS was 4.2 m/minute and the FL was 1.3 m. In the moderate scenario, the RoS doubled to 8.2 m/minute with a FL of 2 m. The low dead fuel moisture scenario showed severe fire behaviour with a tenfold increase of RoS of 81.8 m/min and a FL of 13 m. Given the low CBH:TH ratios, there appears to be a high likelihood of a crown fire at all three dead fuel moisture scenarios.
In sum, measurement of a productive remnant piñón forest showed fuel characteristics consistent with severe fire. Fire behaviour modelling results further supported the likelihood of dangerous and destructive fires. Although the dead fuel loading is not high in absolute terms, this fuel type is not necessarily indicative of the fuel hazard. The forest contains high levels of flashy fuels like grasses and shrubs that permit fire to spread rapidly, coupled with contiguous dead and living vertical fine fuels to carry fire into the forest canopy.
Current vs. desired governance structures
By disaggregating responses by land tenure status and gender, we could identify whether certain groups were satisfied or not with the current form of forest governance. Dissatisfaction amongst specific user groups could potentially complicate management of a shared resource, if those user groups felt that they did not have a fair voice in forest management (Ostrom 1990). There was no statistically significant difference in responses between genders for either ejidatarios (males)/ejidatarias (females) or avecindados (males)/avecindadas (females) for the current versus ideal forest governance ranking exercise. Because there were no significant gender differences in the ranking exercises, we combined the ranking results for the ejidatarios/as and avecindados/as rather than conduct separate Mann-Whitney U tests for each gender.
Under the current governance structure, residents ranked the Comisariado Ejidal as having the most power (50 respondents ranked it first while 88 respondents ranked it within the top three positions). The general assembly and ejidatarios/as were essentially tied for second as having influence. Ranked third, fourth and fifth, respectively, were the community's vigilancia group, the federal government, and the community president who is an elected official in charge of managing community affairs, but who legally has no voice in forest management. Avecindados/as were overwhelming ranked last. Thirty-three respondents ranked avecindados/as last; 80 respondents placed avecindados/as within the last three spots. The government was ranked within the last three spots, in both, the current and desired structure ([Figure 2]).
|Figure 2: Current power structure rankings as compared to the desired power structure rankings|
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The only significant differences in ranking between the current and desired government structure were where the ejidatarios were ranked (Mann-Whitney U, p <.05, 2-tailed), and more significantly, where the avecindados were ranked (Mann-Whitney U, p <.001, 2-tailed). Under the desired structure, avecindados/as were ranked third for whom should have the most power in forest management decisions after ejidatarios/as and the Comisariado Ejidal. Thirty-six percent of respondents stated that everyone, both ejidatarios/as and avecindados/as, should have equal rights. Sixty-three percent of the households comprised solely of avecindados/as and 42% of ejidatarios/as interviewed placed avecindados/as in the top three rankings on how they would like the ejido government to be structured. Respondents said that they felt that avecindados/as should be ranked more highly because in the event of a fire the avecindados/as are the first to fight it, given that they are often younger than the ejidatarios. Respondents also commented that avecindados/as often work hard on the land and help the ejidatarios/as, yet they are ignored at meetings, they are not given permission to collect fuelwood, and they receive no economic benefits from conservation projects.
Overall, although it appears that the community would prefer a restructured governance system, in which, ejidatarios and avecindados are granted more rights as individuals over both the community, state, and federal governments, their desire for change does not appear to affect their willingness to conserve their forest. Avecindados/as and ejidatarios/as were both equally willing to contribute financially to protect the community's forest (Chi-square, p-value >.05). Eighty percent of households responded that they would be willing to contribute to a community fund, and 65% replied that they would be willing to contribute a small, unspecified percentage of their income for continuous forest monitoring.
Community organisation and sanctioning capabilities
Limited organisation and communication within the community and with CONAFOR, and restricted sanctioning capability appear to limit sound forest governance. In the household interviews, interviewees were asked whether they thought CONAFOR projects were beneficial, harmful, or neutral (projects do not cause harm to the forest but they do not improve forest conditions either). Fifty-eight percent responded that the projects were beneficial, 34% said the projects were neutral, and 9% said they did not know either way. None responded that the projects were harmful to the forest. There was no statistically significant difference in response between ejidatarios and avecindados (student's t, p-value >.05, 2-tailed).
In an open-ended question in the household interview, interviewees were asked what the community could do to have better and more effective conservation projects. Fifty-two percent responded with variants of 'better organisation' or 'work better together', in that the community needed to work more cohesively with one another in order to achieve conservation goals. This theme of limited organisation and lack of communication, in which the community self-identified their reduced ability to organise and/or implement conservation projects, was reiterated constantly during the workshops, the oral history interview, and in numerous informal conversations with community members.
Interviewees were also asked whether or not sanctions for breaking forest management and use laws exist (yes/no). If respondents replied 'yes', they were asked whether or not the authorities actually enforced these sanctions and how often they enforced sanctions. Only 4% of respondents said that sanctions for committing illegal forest activities (hunting, starting fires, cutting trees, etc.) were regularly enforced. The remaining respondents stated either that sanctions do not exist or that they do not know of any (55%), or that they do exist but they are not regularly enforced (42%). Limited internal organisation and weak laws, or poor implementation of laws were listed as the biggest social threats in the workshops. Limited jurisdictional capacity and fear of reprisals were listed as the top two reasons why sanctions were not enforced.
High levels of government dependency appear to limit flexibility and mutual learning in conservation projects. In the household interviews, when asked to rank the community's greatest need out of six options (more education, more employment, more government support, better health care, more fertile land, or better protection of the communal forest), 45% listed more government support as one of the top two community needs. Only the need for more employment was ranked higher. An interviewed woman explained, “Government support is what will bring us all of the other stuff like jobs, forest protection, and health care.”
In the community workshops, participants listed ten project opportunities for the community (e.g., types of income-generating projects, conservation activities, etc.); seven of these opportunities involved receiving government support for projects.
Community members, however, complained of poor conservation project management and lack of follow-through by the federal government. In an open-ended question, when asked, what CONAFOR could do to improve conservation projects, 33% said, “más seguimiento” or more follow-through. The second-most common response was that interviewees would like CONAFOR to provide more work (24%). The lack of follow-through generates frustration and mild animosity towards CONAFOR and its extension agents. One community member stated, “They [agents and CONAFOR] are just working for a pay check. If they don't show up, they still get paid. Meanwhile if we [community members] spend a day volunteering or waiting for CONAFOR, we lose our income for that day.”
Environmental threats and fire management options
When asked to rank the greatest environmental threats to their forest, 96% of the households interviewed listed wildfires, both those started within and outside of ejidal boundaries. Eighty-five percent thought that manual treatments like tree pruning and understorey thinning would be effective wildfire mitigation techniques. Sixty-five percent of household interview respondents believed that firebreak construction reduced the risk of fire. Only 15% were in favour of reintroducing grazing to reduce fuel loads. Limited organisation and communication were listed as the biggest limiting factors for land management, including wildfire prevention. Residents who participated in the community workshops also listed wildfire as the greatest environmental threat and poor community organisation (i.e., limited communication and organisation within the community) as the biggest social barrier to sound forest management. Workshop participants were in favour of mechanical thinning as a fuel reduction treatment, and were unanimously opposed to the reintroduction of grazing.
Integrating social and ecological analysis to develop a community fire plan
Based on the results from both the forest inventory and social assessment, we developed a matrix to identify which management options would address both ecological and social concerns ([Table 2]). The most practical short-term management option that both the community and CONAFOR supported was the creation of a local fire brigade. This brigade would initially focus on capacity-building and organisational skills so that in the future they could implement more technical fuel reduction measures such as mechanical fuel reduction activities that would address the ecological fire risk.
| Discussion|| |
What is the forest telling us?
Overall it is apparent that human activities influence what type of fuel and how much fuel is present in these piñón forests. Fuelwood collection practices such as pruning the piñón trees lower branches and collection of downed woody material had a measurable impact on forest fuels, as shown through the high crown base height (distance from the ground to the first live branch), and low amount of woody material recorded through the forest fuel transects. Oral history interviews where participants discussed changes in land-use over time suggest that grazing allowed for a fuel buildup in the forest. Although we cannot quantify this, as we do not have before and after data, community members recall bare landscape prior to the elimination of grazing, whereas now they note heavy vegetative cover.
Grazing was eliminated in SMC´s communal forests in 2003. The 2011 fire, which was ten times larger than any other fire in the recent memory, occurred eight years after grazing was eliminated. Nadar et al. (2007) found that grazing primarily modifies 1-hour and 10-hour fuels, which can dramatically impact flame length and rate of spread. The prohibition of grazing in SMC could possibly have contributed to an increased fuel load, especially grasses and shrubs, which made these forests more susceptible to severe fires.
What is the community telling us?
A significant body of literature demonstrates that land tenure agreements are crucial for managing the commons (Hardin1968; Ostrom 1990; Dietz et al. 2003). While there is no set blueprint for CPR management, communities that have successfully managed a common resource, typically had a set of shared characteristics, including the ability for user-groups to participate in the management, monitoring, and sanctioning process (Ostrom 2008; Van Laerhoven 2010; Baur and Binder 2013).
While SMC has several key elements for successful CPR management, including their commitment to sustainable forest management, they face significant barriers to successful collective action. CPR literature, both within Mexico and globally, argue that all user groups should have a voice in resource management (Ostrom 1990; Dietz et al. 2003; Sarukhan and Merino 2007; Dube 2013; Appiah et al. 2010). A large portion of SMC's CPR user-group cannot participate in management, and the community has limited sanctioning capability. Of the 500 SMC residents who are of voting age, only 133 of them are ejidatarios. As such, only 26.6% of the total voting-age population has the right to participate in forest management decisions, and monitoring and sanctioning processes. Furthermore, the average age of ejidatarios is 75 years old, so most are unable to work on conservation projects in the communal forests (Zamora Vázquez 2012). Their children and other landless community members are the ones who work in the forest, and are the first to fight fires. The result is that the majority of the population employed in forest conservation projects and who put themselves at risk to protect the forest, have no legal say in how it is managed. While currently avecindados appear willing to protect the forest despite their limited rights, more research specifically on ejidatario-avecindado relations is needed to better understand implications of the exclusion of avecindados.
The Mexican federal government also determines what conservation projects to implement at the local level. Because the community depends on the government for much-needed income, they typically do not oppose any project, even if it is not context-appropriate for the landscape. For example, according to CONAFOR regulations, firebreak construction can only be four meters wide and overstorey trees, including the volatile N. parviflora, cannot be removed. Firebreaks in SMC typically have interlocking canopies that can carry crown fires, and are often too narrow to even prevent the spread of surface fires with high flame lengths such as those estimated by fire behaviour modelling in this study. Additionally, community members typically do not receive any training prior to implementing conservation projects, including firebreak construction. As a result, firebreaks are often constructed haphazardly with little regard to fuel type or topography. Dietz et al. (2003) provides examples from fisheries to forest management around the globe that are similar to the situation in SMC in which CPR management failed due to lack of congruence between government regulations and local realities.
A multi-disciplinary approach to wildfire management
This project is a case study that provides valuable insight into the problems that rural and marginalized communities face in managing their shared resources. Using a SES approach, we sought to identify any feedbacks between the social and ecological systems, especially as they related to the wildfire hazard in SMC's communally-managed piñón pine forests ([Figure 3]). Our results demonstrated that human activities directly influenced fuel type and quantity. The fuelwood collection practices and anthropogenic fires all had measurable impacts on forest fuel structure. Concurrently, forest structure and wildfire occurrence had a direct influence on the livelihoods, infrastructure, and organisational capacity of the community. Flashy crown fires put community members' lives at risk, post-fire flooding damaged roads and bridges, and the constant risk of fire challenges current community organisational and governance structures. Thus, there are clear linkages and feedbacks within this particular social-ecological system. Without a sound understanding of both, the social and ecological factors, and their relationship and interactions with one another, we would have an incomplete understanding of the actual wildfire hazards in this human-influenced ecosystem (Redman et al. 2004).
As part of our analysis, we sought to envision a fire management strategy that addressed not only the ecological concerns but the social factors as well ([Table 2]). One option would be to use domestic livestock for fuel reduction. However, 85% of the community opposed this option based on the household surveys. Participants in the workshops also opposed the reintroduction of grazing. Prior to the elimination of grazing, community members commented that the forest was heavily eroded. Now they observe that the forest has many more trees and understorey cover than before, which they consider to be a sign of a healthy forest. The process to eliminate grazing was extremely divisive, and there seems to be little desire to have another fight to reverse the ruling. Furthermore, to implement a sustainable grazing system, internal organisation in the community must be strengthened. The high-level of government dependence may also contribute to its opposition. The reintroduction of livestock would have to be community-initiated because CONAFOR Tlaxcala currently has no sustainable grazing programme. While grazing could be a potential solution in the future, perhaps following a small-scale demonstration, the community preferred to first look at other options that were not as controversial and did not require such a high level of organisation.
|Figure 3: Linkages and feedbacks between the communal P. cembroides subs. orizabensis forests in the ejido Santa María Las Cuevas|
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Mechanical fuel reduction through several of CONAFOR's conservation programmes could also be implemented. In this case community members would be paid to physically remove both understorey and overstorey fuel as well as to prune low hanging branches. Currently CONAFOR pays community members only to construct firebreaks, but CONAFOR has realized that more comprehensive fuel management measures need to be implemented (CONAFOR pers. comm. 2014). While these government projects do not address many of the social constraints, such as organisational capacity, they do provide a temporary income to community members. It would also be a welcome supplement or replacement to the widespread and ineffective firebreak construction.
One viable option presented by the community was the establishment of a community fire brigade, which also addressed some of the larger social barriers to sound fire management. The idea was supported by SMC and CONAFOR. With funding from United States Agency for International Development (USAID) we created a brigade of 28 community members. This brigade was trained in firefighting, and it is equipped with uniforms and hand tools. The goal is to have the brigade become the principal workforce to implement fuel reduction plans in the future. CONAFOR will continue to provide annual trainings for the brigade.
The community brigade addresses several of Ostrom's (1990) design principles for successful CPR management. First, it is inclusionary. Most of the men in the brigade are avecindados who cannot vote. Becoming part of this brigade will allow them to assume leadership roles in forest management, and will enable them to directly participate in the collective action process for CPR management. Second, the brigade emphasizes capacity building, which will provide community members with the skills needed to make more informed decisions regarding the management of their natural resources. Lastly, through working directly with CONAFOR and international agencies like USAID, the community is helping to build multi-scale networks, rules, and guidelines that address local perceived needs.
| Conclusion|| |
The study region is experiencing substantial threats to its small remaining forest. The risk of forest fires in the region has most likely increased within the past 10 to 15 years because of rising temperatures, drought, increased population pressure, and the accumulation of fuel associated with the elimination of grazing. Nearby communities need to be included for effective implementation of a fire management strategy. The results and lessons learned from this case study can serve as a base for an expanded regional fuel mitigation strategy.
Fire management can be a key part of a much broader strategy for stronger community forest management. Effective fire management requires sound scientific understanding of the ecological conditions of the forest, strong institutional support and collaboration, and a more cohesive community voice in the planning and implementation process; all of these needs are also critical for sound forestry management in general.
Communities should be allowed more input and flexibility in managing their CPRs so that money, time, and social capital are not lost on projects that are not context appropriate. Multi-disciplinary diagnostic tools like the one used in this project can help government agencies examine barriers to collective action and enable both agencies and communities to develop integrated management plans for the communities' common-pool resources.
| Acknowledgements|| |
We thank the Ejido Santa María Las Cuevas, CONAFOR Tlaxcala, and Servicio Forestal Altiplano, A.C., Leticia García Ortega, Eder de Jesus Cuatianquiz Montiel, Eulogio Quiróz Lucas, Mary Hektner, Daniel Lathum, Dr. Vidal Guerra de la Cruz, Larissa Yocom, Citlali Cortes-Montaño, Thomas Sheridan, and Christine Szuter. USAID provided financial support for the fieldwork. 
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[Figure 1], [Figure 2], [Figure 3]
[Table 1], [Table 2]