Participatory Restoration of Degraded Agricultural Areas Invaded by Bracken Fern (Pteridium aquilinum) and Conservation in the Chinantla Region, Oaxaca, Mexico

Participatory Restoration of Degraded Agricultural AreasInvaded by Bracken Fern (Pteridium aquilinum)and Conservation in the Chinantla Region, Oaxaca, Mexico

Carolina Berget1 & Elvira Duran2& David Barton Bray1

# Springer Science+Business Media New York 2015

Abstract Invasions of bracken fern, Pteridium aquilinum, arean important source of agricultural degradation in many tropicalareas.We present a case study of apparent historical degradationof agricultural land which, combined with recent conservationmeasures, may have created new pressures on food production.Our study of two communities in the Chinantla region, Oaxaca,Mexico is based on interviews and documentation of low farmerawareness of the anthropogenic origins of bracken fern inva-sions, local knowledge of control techniques and the social-ecological implications of bracken degraded areas. A modelfor a potential participatory restoration project based on ongoingcollective action processes in the communities is proposed. Fi-nancial support is needed to incentivize farmers to participate inrestoration efforts, to recover productive lands and improve lo-cal livelihoods. Agricultural restoration efforts would contributeto sustainable multifunctional landscapes.

Keywords Restoration . Degraded agricultural areas .

Invasive ferns . Conservation and food security .

Collective action . Agroforestry .Mexico

Introduction

Concern about the trajectory of tropical landscapes has fo-cused on both the need to conserve existing natural ecosys-tems and on restoration of degraded areas. Most of the work

on restoration of tropical landscapes has focused on restoringforests, and their associated biodiversity and ecosystem ser-vices (Lamb et al. 2005; Chazdon 2008). Although proposalsfor forest restoration acknowledge the importance of goodsand ecological services from forests, we argue that they shouldalso take into account a parallel need to improve food produc-tion from degraded landscapes in tropical areas marked byrural poverty and food insecurity (Lamb et al. 2005; Foleyet al. 2011). It has been argued that addressing conservationand food security requires both a reduction of the expansion ofagriculture into sensitive ecosystems and a closing of theByield gap^ in Bunderperforming landscapes…where yieldsare currently below average^ (Foley et al. 2011:339). Foleyet al. (2011) propose reforms of conventional agriculture andtaking lessons from organic and precision agriculture, but donot take into account the need to recover agricultural lands thathave been so degraded as to cease producing food entirely,which is the case when degraded agricultural lands have beenoccupied by the invasive bracken fern Pteridium aquilinum.

The bracken fern Pteridium aquilinum [L.] Kuhn is a nat-ural component of semi-open woodland areas of almost everyforest throughout the world, where it usually occurs at lowdensities. However, when fully exposed to light it becomesexplosively invasive (Hartig and Beck 2003; MacDougallet al. 2004; Schneider 2004; Harmer et al. 2005). Bracken’slarge rhizome system contains nutrient reserves that lead tomany buds capable of producing new fronds, and its highproductivity produces a frond canopy that projects deep shade.In addition, its allelopathic effects can prevent the establish-ment of other plant species (Marrs et al. 2000). It is also aspecies known for its fire-adaptability and its highly flamma-ble layer of dried fronds (Crane 1990). Problems with arrestedsuccession and loss of agricultural land due to degradation bybracken fern in inhabited tropical forest regions around theworld have been documented, notably in Rwanda, Brazil,

* Carolina [email protected]

1 Florida International University, Miami, FL, USA2 Centro Interdisciplinario de Investigación para el Desarrollo Integral

Regional-Oaxaca, Instituto Politécnico Nacional, Oaxaca, México

Hum EcolDOI 10.1007/s10745-015-9762-0

Ecuador, and the Dominican Republic (Hartig and Beck 2003;Slocum et al. 2004; Pejchar and Mooney 2009; Matos andBelinato 2010; TGC 2011; Knoke et al. 2014). There are nofigures available on the global magnitude of tropical landsdegraded by bracken fern, but Schneider and Fernando(2010) have demonstrated that it expanded explosively inMexico’s southern Yucatan Peninsula, increasing from40 km2 in 1989 to 80 km2 by 2010.

Additional reports of bracken fern in Mexico come princi-pally from the tropical regions of the southern states (Schneider2006; Douterlungne et al. 2008; Levy-Tacher et al. 2013;Suazo-Ortuño et al. 2015), where it also appears to be wide-spread, especially in Oaxaca, the focus of this paper (Edouardet al. 2004; Berget 2012). Favorable conditions for bracken fernestablishment are created by traditional agricultural systemssuch as swidden agriculture and its associated fire practices.The explosive growth in the southern Yucatanmentioned aboveappears related to larger parcels that are regularly burned(Schneider 2006) but it is not clear how traditional practiceson smaller plots lead to bracken fern invasions over longer timeperiods. Agricultural lands invaded by bracken fern both losetheir productivity potential for the next agricultural cycle andremain in a degraded ecological state in which the secondarysuccession is arrested. Thus, the widespread invasion of brack-en in inhabited landscapes may cause: 1) threats to livelihoodswhen farmers need to travel long distances to establish agricul-ture plots and obtain forest resources like firewood, 2) threats tofood security in communities where agricultural areas are lim-ited and fallow periods are shorter and 3) potential pressure onforests and impacts on biodiversity habitats. Most farmers insouthernMexico tend to abandon the bracken sequestered plotsand open new forest lands to establish agricultural areas(Schneider 2004; Suazo-Ortuño et al. 2015) since there havecommonly been land surpluses. However, some attempts atrestoration of agricultural lands have been documented(Edouard et al. 2004; Douterlungne et al. 2008) and we buildupon both local knowledge and these prior experiences in thisarticle. Ibarra et al. (2011) proposed that conservation restric-tions in this region may be impacting food security, but theirstudy did not take into account the existing constraint of de-graded bracken fern areas (see below).

Analyses of biological invasions have focused on the eco-logical consequences for ecosystem services and structure,environmental productivity, biodiversity, and other aspectsof ecosystem functions (Rey Benayas et al. 2009; Suazo-Ortuño et al. 2015), but much less on impacts on food pro-duction. Addressing invasive species has also beenapproached as primarily a technical issue of the optimal waysto eradicate the species. There has been less focus on thedynamics of biological invasions in coupled human-ecological systems in which the Bbiological nature of plantinvasions is explicitly linked to social, economic, and culturalcauses of land transformation^ (Schneider 2004:230) and how

such invasions may lead to a reduction in food security in de-veloping countries (GISP 2008). While Turner et al. (2003) ar-gue that bracken fern invasion in the southern Yucatan Peninsulaconstitutes a new hazard for the coupled human-environmentsystem, they do not consider how both the demands for conser-vation in this area and the bracken fern invasion have impactedfood production, nor do they consider any agricultural restora-tion efforts as a response to the dilemmas presented by theconservation-bracken fern pressures on food production.

Bracken affects many community lands in the tropical for-ests of the Chinantec indigenous region of Oaxaca where forcenturies people have practiced traditional swidden agricul-ture (Weitlaner and Castro 1973; Bevan 1987). Nonetheless,studies conducted in this region have not until now taken intoaccount the ecological degradation due to bracken fern (Vander Wal 1996; CAMPO 2009; Ibarra et al. 2011; Bray et al.2012). The need to balance forest conservation and restorationof degraded agricultural lands at the level of tropical ruralcommunities where these dynamics play out requires a con-sideration of not only ecological principles, but also the socialdynamics and local knowledge of the affected communities(DellaSala et al. 2003; Rey Benayas et al. 2009). In this paper,we document the detrimental social-ecological dynamics ofbracken fern invasion in a small watershed inhabited by twocommunities in the Chinantla region, where bracken invasionhas obliged farmers to find new agricultural areas in forests farfrom their settlements. Bracken poses concerns for its poten-tial expansion to current agricultural areas that in turn couldcreate pressure on forests in the future. The objectives of thispaper are to: 1) characterize the presence of bracken in thestudy site, 2) report on local perceptions and knowledge ofthe bracken invasion and the relationship of these degradedareas to recent conservation initiatives, 3) analyze the potentialfor a participatory restoration project of bracken degradedareas derived from local knowledge on fern managementand control, and 4) develop a model for bracken restorationtaking into account social-ecological dynamics.

Study Site

This research was conducted in the Santiago river watershed(~12,235 ha), located in the Chinantla Alta region, between17°22-18°12 N and 95°43-96°58 W, in the municipality ofSan Felipe Usila in Oaxaca, Mexico. The common propertylands of two Chinantec communities, Santiago Tlatepusco (5,945 ha) and San Pedro Tlatepusco (6,289 ha), hereafter San-tiago and San Pedro, are located in this region (Fig. 1).Santiago’s population is estimated at 591 inhabitants, ofwhom 151 are comuneros (members with legal rights to makedecisions regarding common property management). SanPedro’s population is approximately 200 inhabitants, of whom50 are comuneros. The communities have common property

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territories under Mexican agrarian law, with governance bythe Assembly of comuneros with elected authorities. Thecommunities have reportedly been in this area for at least athousand years (Bevan 1987; De Teresa 2011). Elevationsrange from 200 to 2,000 m. Slopes range between 10 and50° in an abrupt topography, and it has been characterized asone of the rainiest regions of Mexico (Velazquez-Rosas andMeave 2002). Above 1,000 m, tropical montane cloud forestsand pine forests are the dominant vegetation cover. On theslopes below 1,000 m, a mosaic of native vegetation and an-thropogenic land uses is found, with tropical rain forests,Quercus forests, coffee fields, milpas, pastures, and humansettlements. Also, at the lower elevations, shrub-grasslandvegetation mixed with bracken fern areas prevail, primarilylocated on the slopes directly above the population centerswhere it forms dense cover (Fig. 2a and b).

The Santiago river watershed is part of the Sierra NorteRegion of Oaxaca, which is considered a BPriority Area forBiodiversity Conservation^ (Arriaga et al. 2000; CONANP2005; CONABIO 2007, 2010). The Chinantla region is con-sidered a biodiversity hotspot and, specifically in both studycommunities’ lands species such as jaguar (Panthera onca)and other felines have been identified (CONANP 2005; Figelet al. 2011). Since the mid-2000s, the two study communitieshave been members of an inter-community organizationknown as the Regional Natural Resource Committee of theUpper Chinantla (Comité Regional de Recursos Naturales dela Chinantla-CORENCHI). In 2004, both communities vol-untarily set aside a large amount of their territory as

community conserved areas (at least 70% (~9,350 ha) of thecommunal lands (12,803 ha)) (Bray et al. 2012). These con-served lands are known as Voluntary Conserved Areas (VCA)and are recognized as part of Mexico’s protected area system.In addition, since that date, the communities have been en-rolled in a Payment for Hydrological Services Program (PHS;approximately 45% (~5,769 ha) of the lands) to receive mon-etary compensation for forest conservation. Prohibition ofland use change is the only stipulation required by the gov-ernment agency (CONAFOR) that regulates the PSH pro-gram. To comply with this requirement, communities createdinternal regulations to make restrictions regarding where topractice agriculture, committed to build fire breaks aroundthe agricultural plots in preparation for cultivation, and includ-ed a self-imposed hunting ban. This ban allowed for huntingof nuisance animals in the agricultural areas. However, thedegraded areas are not considered agricultural lands so thecommunity regulations do not permit hunting in these areas(see below) (Berget 2012). As noted earlier, it has been arguedthat these conservation programs and associated regulationshave reduced food security (Ibarra et al. 2011).

The majority of comuneros are heads of household, theproductive unit in the communities (Weitlaner and Castro1973; De Teresa 2011). There are three main agricultural landuses: 1) milpa, the subsistence crop/system typically com-posed of maize (Zea mays), beans (Phaseolus vulgaris) andsquash (Cucurbita moschata); 2) coffee, as the main cashincome generating crop; and 3) yucca (Manihot esculenta)and pineapple (Ananas comosus), which are complementary

Fig. 1 Santiago river watershed.Bracken fern and humansettlements location and generallocation of agricultural areas andcoffee plots

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subsistence crops consumed by households to diversify theirdiet and are never sold commercially. Household milpa andcoffee plots vary in size (0.25-5 ha), while yucca and pineap-ple plots are significantly smaller (~0.25 ha). Milpa is prac-ticed by the majority of households (97%) under traditionalswidden cultivation (active 1 to 2 years, and varying years infallow). Coffee, grown under shade trees in plots used fordecades, is cultivated by 86% of households. Yucca (71% ofhouseholds) and pineapple (31% of households) have beensuccessfully used to restore small portions of the bracken in-vaded areas and their plots are utilized for periods of approx-imately 5 years, depending on the soil quality and the impactof nuisance animals.

By Mexican government poverty measures, the communi-ties are considered extremely marginalized (Berumen 2007;

Velasco-Murguía et al. 2014) and their lack of roads and rel-atively remote location makes them heavily dependent on lo-cal food production (Ibarra et al. 2011).

Methods

Consent from community authorities and the Assembly ofboth communities was obtained to conduct the study. Thecommunities, part of a larger research project of a Mexicanand a U.S. university, are an unusual case of collective inter-community conservation efforts (Bray et al. 2012; Duran et al.2012). Research, using a variety of methods, was carried outbetween 2010 and 2014. Participant observation was conduct-ed in several community assemblies, workshops and

Fig. 2 a Landscape view of hillsinvaded by bracken fern; b Close-up of growing bracken; c Yuccaplot located in an area previouslyinvaded by bracken fern; dGrowing pineapple in a plotpreviously invaded by brackenfern; e Woman harvesting yuccaand bananas; f Yuccas destroyedby nuisance animals

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agricultural activities. Five guided walking-transects in thebracken invaded lands were conducted with systematic fieldnotes taken. Geo-referenced data points were obtained duringthe guided walking-transects in bracken fern and adjacentareas. The watershed was delimited using a digital elevationmodel at a 30 m resolution, utilizing the program ARCGIS10.1. The geo-referenced data points of the areas of fern werelocated using Google Earth images, whereby polygons ofareas were delimited with and without the fern. These poly-gons were used as reference data in order to create a super-vised classification using LANDSAT 8 OLIS (http://glovis.usgs.gov/). The locations of milpas and coffee plots weremarked on the map resulting from the supervisedclassification.

During 2010, 11 semi-structured interviews of over an hourwere conducted with key informants from the communities(community leaders, community members, CORENCHIleaders, and elders). On the basis of these preliminary inter-views, a structured interview instrument was developed(Bernard 2002; Nardi 2003; ESRC Research Group 2004)and administered in 2011. Structured interviews consisted of133 questions, divided in four sections: 1) household mem-bers and their participation in agricultural activities; 2) agri-cultural activities, the number and size of plots, rotationalcycles, and bracken invasiveness; 3) knowledge and percep-tions of Pteridium aquilinum, local control techniques, moti-vations to control it, and nuisance animals present in invadedareas; and 4) conservation areas, focusing on availability ofagricultural areas and hunting bans.

Structured interviews lasted between 45 and 97 min andwere conducted at the household level (77% with the assis-tance of a translator). In Santiago, interviewed householdswere randomly selected from the list of comuneros. In SanPedro the majority of the households were visited, and thehouseholds with an available and willing comunero wereinterviewed. In total, 46 interviews were administered (24 inSantiago and 22 in San Pedro), accounting for almost 38% ofthe total households in the watershed. Both women (6) andmen (40) were interviewed. Although women are active par-ticipants in many agricultural activities in these communities,heads of household are generally men. Women interviewedwere heads of household, usually widows with no adult malechildren, or were designated by the male head of household torespond to the interview.

The interviewees’ responses were concentrated inMicrosoft Excel spreadsheets. Descriptive statistics compar-ing the percentages of responses for questions related tofarmers’ knowledge, perception and management of brackenfern were developed. Statistical analyses comparing walkingdistances in minutes from the towns to the different agricul-tural plots (milpa, yucca and pineapple) and the size of plots,with and without bracken, were made using a non-parametricKruskal-Wallis test, at p<0.05 significance level. Because

invasive bracken is common to the two communities, andthere are no cultural, social, agricultural or ecological differ-ences between them, the analysis was made at the Santiagoriver watershed level, merging the two communities.

Based on the bracken control and management activitiesthat farmers practice in the invaded areas and on farmers’expectations regarding more productive land uses, a modelof the current and potential dynamics that can occur in thebracken degraded areas was developed. This restoration mod-el illustrates the transition routes that could lead to rehabilita-tion of bracken degraded areas.

Results

There is essentially no farmer awareness that the origin ofbracken fern is almost certainly anthropogenic or the exactextent of the problem. For all living farmers it has always beenthere. The oldest interviewees (ages 69 to 94) report that fromtheir earliest memories bracken was already present on theslopes above the communities. Eighty-nine percent believedthat it had existed for at least 50–100 years, because theirparents and grandparents told them it had been there all oftheir lives. Farmers also display little appreciation or knowl-edge of how extensive the bracken-invaded area is. Whenasked the size of the area dominated by the fern, 69% couldnot give a precise figure, saying only that it was Ba lot^ whilethe remainder mentioned figures ranging from 500 to 1,500 ha. Fifty-one percent of the interviewees believe thatbracken areas have not changed in size, 34% think the areashave increased, and only 14% believe the areas have dimin-ished. Our analysis suggests that bracken fern covers at least465 ha mostly between 400 and 1,000 m (Fig. 1). From thelocation of bracken in relation to agricultural areas (milpa andcoffee) it is evident that the majority of the invaded areas areon the slopes immediately surrounding the communities, withonly a few in more distant areas (Fig. 1). We estimate that thedegraded bracken fern area represents around 14% of the areacurrently or potentially available for agriculture. We do nothave historical images which could illustrate the changingdynamics of the area, but responses suggest that it has beenrelatively stable for a considerable period. This local domi-nance of the plant has obliged farmers for many decades toestablish their agricultural plots in forests at a greater distancefrom their settlements. Significant statistical differences (p≤0.05) were found between the average distance a farmer has towalk to their yucca or pineapple plots (22 min ± 10) farmed onthe slopes near the community versus the distance they have towalk to milpa plots (81 min ± 40) (Fig. 2a and b). However,some of these more distant agricultural plots have now beenaffected by the conservation areas established in both commu-nities’ territory in the mid-2000s. Forty-one percent of thefarmers had milpa in what are now the conservation areas,

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and had to abandon these plots with the advent of the conser-vation programs. This would appear to be a very significantdislocation of food production due to conservation policies.However, the vast majority of all those interviewed (82%) saidthat there is still sufficient agricultural land available, that thelands now with restricted access were not necessary for foodproduction. Although a notable minority (18%) does feel thatthere is insufficient agricultural land, this opinion did not ap-pear to be tied to restricted access in the conservation areassince several of these respondents did not have agriculturalplots there.

Although bracken fern is regarded as a natural part of thelandscape, 91% of the farmers perceive it as a problem be-cause it inhibits other potential uses. The degraded hillsidesnow produce only very limited quantities of yucca and pine-apple (Fig. 2c and d). We estimated that yucca and pineapplecrops occupy only ~26 ha or 5.3% of the total estimated in-vaded areas of ~465 ha. Almost all farmers (94%) have pine-apple or yucca in invaded areas. This limited restoration of thedegraded areas is based on local knowledge of how to controlthe bracken by removing the fern and generating shade toinhibit the bracken’s growth. The removal technique involvesmanually cutting it with machetes and/or pulling the roots upby hand, then burning the plot. This was followed by plantingone of the two crops to generate shade. While the crops aregrowing, bracken is controlled by manually pulling it out. Theplots can thus be maintained continuously in production forperiods of several years. Two-thirds of the informants statedthey inherited the knowledge for bracken fern control fromtheir parents and grandparents. Thirty percent said they taughtthemselves via trial and error, and the other 6% said theylearned from observing others. Since women in the commu-nities are active participants in agricultural activities (they do50% of sowing, weeding and harvesting and 83% of firewoodgathering), the six interviewed women were knowledgeableand had participated in activities related to bracken control(Fig. 2e).

Although these two crops grow well in degraded areas, itrequires constant clearing and maintenance after the harvest orthe fern re-invades the plots rapidly. All interviewees saideliminating it demands approximately four times more laborthan clearing secondary forests for milpas. It is exhaustingbecause there are no trees to provide shade from the sun andbecause cutting and pulling the roots by hand requires sub-stantial physical energy and time. There are also safety risks,since the density of the fern diminishes the visibility, increas-ing the vulnerability to snake bites. Also the highly combus-tible properties of bracken fern may provoke fires that canquickly get out of control.

Nuisance animals that attack yucca and pineapple produc-tion are another problem that reduces interest in further resto-ration (Fig. 2f). Nearly all respondents noted seven mammalspecies considered nuisance animals that utilize bracken fern

areas as refuge, based on images in a wildlife guide (Beletsky1999) and two-thirds of the interviewees think that the invad-ed areas increase the number of nuisance animals. Farmersreported that white-nosed coati (Nasua narica), collared pec-cary (Pecari tajacu), Mexican agouti (Dasyprocta mexicana),squirrel (Sciuris spp.), paca (Agouti paca) and Northern rac-coon (Procyon lotor) repeatedly attack yucca and milpa crops,while pineapple crops are attacked by opossum (Didelphisopossum) and white-nose coati. In addition, the farmers re-ported a bird species that attacks pineapple crops, most likelyPsarocolius montezuma. Finally, 97% of the sample consid-ered that the establishment of conservation programs and as-sociated conservation measures, particularly the self-imposedhunting ban, has caused an increase in the number of nuisanceanimals.

In two-thirds of cases, once the plot is abandoned it isreinvaded by the fern. However, in about one-third of thecases, farmers have continued caring for saplings which havesprouted in the fields and a managed natural succession hasfollowed, indicating that restoration pathways are possible.Two examples were reported. One household reported a suc-cessful restoration effort in which a yucca plot developed sec-ondary succession for 6–7 years and at the time of the inter-view they were planning on felling the young trees and culti-vating maize in that plot. If this occurs it would be an exampleof a successful return to annual agriculture. In several othercases, farmers were able to continue suppressing the fern withbananas (Musa paradisiaca), pine (Pinus chiapensis) and ce-dar (Cedrela sp.). One respondent stated that BI planted cedarin a bracken invaded area and it is growing well…..cedar is atree species known for its good and high-valued timber, and itthrives in prior bracken invaded areas.^

However, these successful efforts at restoration have oc-curred on only a tiny percentage of the entire degraded area.We thus wanted to explore local perceptions of the possibili-ties of restoring the entire or most of the area. Half of theinterviewees believe that it would be possible but extremelydifficult to restore all the invaded areas to secondary succes-sion, forests, or crops. The remainder believes restoration isimpossible, mainly due to the amount and intensity of laborrequired. Thus, clearly restoration of these degraded agricul-tural areas presents a major challenge to the communities.However, when asked if it would be possible to recover theinvaded areas if economic incentives existed and what otherland uses they would like to see (with more than one choiceallowed), theymentioned: 1) secondary forest lands that couldbe converted to milpa (97%), 2) forest (94%), 3) coffee fields(60%), and 4) other crops, including yucca and pineapple(40%). Based on these scenarios, along with a better under-standing of the magnitude of the invasion provided by thecartographic analysis (Fig. 1), we developed a model of fourmore desirable social-ecological pathways for restoration ofthe bracken areas (Fig. 3) (see Discussion).

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Discussion

This case study of the dynamics of agricultural degradationand conservation in a tropical landscape suggests some of thechallenges to creating pathways for restoring sustainablemulti-functional landscapes (O’Farrell and Anderson 2010).This watershed constitutes an Bunderperforming landscape^(Foley et al. 2011) where the invasion of bracken fern hastaken hundreds of hectares out of production, apparently formany decades.We argue that proposals for restoration of trop-ical landscapes focus not only on forests (Chazdon 2008) butalso on restoration of degraded agricultural areas. Scherr(2000) has pointed to the issue of farmer awareness as a con-straint to positive adaptation in situations of natural resourcedegradation and mentions the possibility of causal factors ofthe degradation not being observable to the farmers. We havedocumented just such a case of the absence of farmer aware-ness of the very probable anthropogenic origins of the pres-ence of bracken fern, which indeed presents a constraint onrestoration.

We know from the literature that bracken fern invades de-graded agricultural areas (Edouard et al. 2004; Lawrence et al.2004; Schneider 2006; Douterlungne et al. 2008), but it hasbeen suggested that the explosive growth of bracken fern inthe southern Yucatan Peninsula is associated with regularlyburned large parcels (Schneider 2006; Schneider andFernando 2010). The fact that bracken fern appears to havebeen relatively stable for years in the watershed suggests adifferent ecological pathway for bracken invasions. The twostudy communities have been in the same area for hundreds ofyears. Thus, a probable scenario is that their ancestorsestablished their villages in areas where the most accessiblesurrounding slopes were suitable for agriculture but subse-quently became degraded after centuries of cultivation and fireuse, suggesting a different and less explosive ecological path-way for bracken fern invasions. This forgotten bracken inva-sion would have caused the dispersion of farmers into thelarger territory seeking new agricultural lands, given the his-toric ready availability of land, as currently happens whenfarmers experience contemporary bracken fern invasions in

Fig. 3 a Historical, current andpotential transition routes ofnatural and productive cycles inthe Santiago river watershed; bFour models towards moredesirable scenarios; 1) Bracken tomilpa; 2) Bracken to commercialtree species*; 3) Bracken tocoffee; 4) Bracken to yucca/pineapple. * Secondarysuccession for multiple forest uses(commercial tree species,firewood, construction material).** Including other agroforestrysystems (like cacao and fruit

trees). Natural disturbance

Bracken Forest

recovery Agricultural

production

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the southern Yucatan Peninsula (Turner et al. 2003). Thus,because multiple generations have been growing milpas inmore distant bracken-free areas, the current 1.5 h treks re-quired to reach them do not seem excessive. In addition theChinantec have historically lived in extremely isolated areasand have a tradition of walking long distances (Bevan 1987).Nevertheless, farmers need to carry heavy loads of harvestedproduce, firewood and agricultural tools along very steeppaths with consequent health costs. The local physician re-ported that the farmers frequently complain of back and kneeproblems from carrying heavy loads.

Currently, this historical dispersion into more distant for-ests has been restricted by the introduction of conservationmeasures that restrict the availability of new land for agricul-ture. Since 2004 some 70% of the communal lands in bothcommunities were certified as indigenous/community con-served areas, managed by inter-community collective actionthrough CORENCHI. Some 45% of the total territory, allwithin the VCAs, receive payments for hydrological services(Bray et al. 2012). VCAs are generally certified for a 25 yearperiod, although communities can request their revocation atany time, and the PHS programs are 5 year contracts. As a partof the process, the communities decided to also impose ahunting ban in the VCAs, which is not required by eitherconservation measure, although hunting is still permitted ofnuisance animals in the zoned agricultural areas. For thecommunity of Santiago, Ibarra et al. (2011) have providedconsiderable evidence that the restrictions on agriculture inthe VCAs have resulted in shorter fallow periods and reducedyields, and that the self-imposed hunting ban has reducedmeat consumption and increased nuisance animals in the mil-pa. This, combined with the income from the PHS program,they argue, has produced a greater reliance on purchasedfoods and deleterious impacts on food self-sufficiency in gen-eral. Our data are limited to the specific issue of whetherfarmers perceive the VCAs as having reduced suitable agri-cultural land, but our findings do not support Ibarra et al.’scontention of widespread impacts on access to good agricul-tural lands, with only 18% of farmers reporting reduced accessdue to the VCAs. Further, it should be noted the greater avail-ability of cash to buy foods is not only from the PHS pro-grams, but also comes from other government transfer pro-grams and remittances, and that changes in diet and food self-sufficiency respond to other long-term trends not noted byIbarra et al. (2011). Finally, the VCA can be revoked by thecommunity at any time, as can the self-imposed hunting ban.

However, as Ibarra et al. (2011) note, it is likely that theVCAs by placing limits on the historic land surplus conditionhave increased pressures on food production at least margin-ally. It is also likely, as they note, that scattered agriculturalopenings in the VCA do no ecological harm, and are part of along-term diversified land use mosaic. The twin pressurescould lead to more intensive use of the current agricultural

areas with more frequent burning, creating conditions of dis-turbed areas that would favor bracken establishment. There isevidence of the negative effects that bracken can impose overagricultural areas, forest ecosystems and landscapes in rela-tively short periods of time when farmers do not control it(Schneider 2006; Knoke et al. 2014).

Thus, the possible reduction of food production due to theVCAs can be reversed virtually at any time by communitydecision. However, the reduction of food self-sufficiency cre-ated by degraded agricultural areas due to bracken fern is notvisible either to the farmers or to outside agents such as NGOsor the government. Given the costs in terms of health and foodsecurity of the degraded lands near the community, it is im-portant to address the question of why farmers have notattempted to recuperate the bracken invaded areas more sys-tematically for agricultural purposes. Our results suggest fivemain reasons: 1) farmers think bracken occurs naturally in thelandscape; 2) bracken control is very time-consuming andthus expensive; 3) it is dangerous because of the risk of snakebites; 4) yucca and pineapple are complementary food itemsfor household consumption and current production would ap-pear to satisfy that demand; and 5) nuisance animals attack theyucca/pineapple harvests, reducing farmer benefits.

Thus, any proposal to restore these degraded areas has toaddress these significant challenges. We suggest that there arethree key factors that could change the incentive structure forrestoration of degraded lands: 1) increase in farmer awarenessof the anthropogenic origins of the bracken fern, 2) support forcommunity discussions on collective action and participationin an agricultural restoration strategy, and 3) economic incen-tives for elimination of bracken fern. The goal would be alandscape restoration that could create a mosaic of agricultureand forest patches in the degraded areas with an approach thatis participatory, adaptive and quantifiable, and that addressessocial wellbeing and ecological improvements (Newton2011), which could provide a model for restoration of degrad-ed and underperforming landscapes elsewhere.

In recent years, in connection with conservation programs,the study communities have been encourage to participate inworkshops on conservation, payments for environmental ser-vices, land use planning, participatory mapping, ecotourismand improved coffee production methods. Workshops on thescientific knowledge of bracken fern invasion and the costs tothe community would complement these. Increased farmerawareness could then lead to the participatory design and im-plementation of ecological restoration based on local knowl-edge and techniques (Egan et al. 2011; Newton 2011; Knokeet al. 2014). In addition, participatory workshops could helpthe communities address the problem of nuisance animals indegraded areas (Treves et al. 2009). Currently, the degradedareas are not zoned as agricultural areas by the communities,and thus by their own rules hunting is not allowed, making itdifficult to control the populations of nuisance animals. A

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participatory analysis of the problem could lead to a change inthe community rules.

Scherr (2000) notes the importance of community collec-tive action in addressing natural resource degradation. Thesecommunities, and many communities elsewhere in Mexico,have a strong tradition of collective action through communitygovernance with monthly assemblies, community rules (in-cluding hunting regulations and strategies like fire breaks)and land use planning exercises (Velasco-Murguía et al.2014). They also engage in the intercommunity organizationCORENCHI, coordinating a regional conservation and devel-opment strategies and establishing agreements with state andfederal agencies in a multi-scale governance approach for thenoted conservation and development activities (Bray et al.2012). This suggests that with appropriate incentives this col-lective action tradition could be mobilized for agriculturalrestoration.

However, economic incentives will be necessary since the-se communities are poor, marginalized and dependent on sub-sistence agriculture (Velasco-Murguía et al. 2014) and brack-en fern control is time-consuming and hard work. Currentpayments for hydrological services or a similar program ofsubsidies could be targeted at restoration of agricultural areas,which would also relieve pressure on the conservation areas.Given that women are heavily involved in agricultural activ-ities, financing programs should target not only heads ofhouseholds but also any women interested in participating ina restoration project. Women do 83% of the firewood gather-ing and thus would benefit from restoring degraded areascloser to home.

Finally, we propose a model for varying pathways thatcould be used for restoration of degraded agriculturalareas in this and other similar multi-functional landscapesin Latin America and globally. This model includes thefarmers’ goals for a restored area as expressed in the sur-vey, principally gaining new agricultural areas and forest-ed patches for firewood, timber and fruit harvests, creat-ing a mosaic of agriculture and forest patches in a local-ized land-sharing approach (Phalan et al. 2011; Padochand Sunderland 2013; Fig. 3a). We suggest four social-ecological pathways (Fig. 3b) with each pathway depend-ing on farmers’ preferences to create a particular config-uration of ecological restoration: 1) cultivate yucca/pineapple to encourage trees for secondary succession thatcan then be converted to milpa cultivation; 2) encouragetrees for secondary succession for multiple forest uses(including planting commercially valuable trees for har-vest in future years); 3) cultivate yucca/pineapple to thenencourage trees for a secondary succession where shade-coffee can be grown, as well as cacao and other fruittrees; and 4) cultivate yucca and/or pineapple, encouragesecondary succession, and then again cultivate yucca and/or pineapple. This model for participatory restoration

should involve local people in the design of a strategyfor Bproductive restoration^ (FAO 2014) of degraded ag-ricultural areas, including the design of the subsequentexecution and monitoring phases.

As additional pathways, taungya and improved fallowagroforestry systems could also be explored. In taungya,once bracken fern is successfully eliminated, corn isplanted along with useful trees; the corn can be harvestedfor 1–2 years until the trees begin to cast more shade.Improved fallow is traditional fallow (abandoned agricul-tural phase in which secondary vegetation develops, com-posed of native tree species) enriched with timber trees(Soto-Pinto et al. 2010). Planting legume cover crops canalso be used to continue to suppress the re-emergence ofthe bracken fern (Mercer et al. 2005). The idea behindthese agroforestry systems is to have short, medium andlong-term production, starting with annual (milpa) andperennial crops (yucca and pineapple), potentially follow-ed by fruits and finally by timber (Mercer et al. 2005).

Recently, agroforestry systems, including shade-coffeeplantations, have been recognized as important carbonsinks. The establishment of taungya systems, improvedfallow and shade-coffee parcels in degraded bracken fernareas have the potential of accumulating significantamounts of carbon and could be used to obtain financingfor restoration community efforts through entering thevoluntary market of carbon sales under the Payment forEnvironmental Services (PES) scheme, as has been thecase in other indigenous communities in Oaxaca and Chi-apas (Soto-Pinto et al. 2010; Bray 2012). Informants inour study site recognized that some trees, especially thosethat serve as firewood, can grow in the invaded areas.Efforts to restore bracken fern areas could include plant-ing tree species suitable for this region that could accel-erate the restoration process by serving as nurse-tree spe-cies to facilitate regeneration (Knoke et al. 2014). Forexample, Quercus glaucencens is naturally abundant inpatches close to the bracken fern areas, and is widelyaccepted among the farmers as a good firewood source(Van der Wal 1996). A study in an adjacent communityto the Santiago watershed identified some native tree spe-cies (Ocote sp., Ficus sp., Casearia sp., Psychotria sp.,Ilex sp., Prunus sp. and Calyptranthes sp.) (Rincon-Gu-tierrez 2007) that could be used in an agro-forestry projectfor carbon sequestration, and as has been the case inRwanda (TGC 2011). Because both communities maintainhighly diverse tropical forests for conservation, whichharbor endangered species like jaguar and other carni-vores (Figel et al. 2011), restoration initiatives should alsobe supported by Mexican conservation programs based onstrengthening productive systems like traditional milpa orshade-coffee (Rosas 2013), or other international mecha-nisms like REDD+ (Newton 2011; COFO 2014).

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Conclusions

The principle concern of most research and proposals on res-toration of tropical landscapes has focused on forest restora-tion services (Lamb et al. 2005; Chazdon 2008). Forest resto-ration may provide some food sources and ecosystem servicesfor poor rural communities, but annual agriculture will remainthe mainstay of food security in most tropical landscapes. Thispoints to the need to restore landscapes which areunderperforming in terms of food production (Foley et al.2011) while also conserving tropical forests. We have exam-ined a case study of two communities in a single watershed inthe Chinantla region of the Sierra Norte of Oaxaca, wherequestions have been raised about the role of conservation pro-grams in food security or self-sufficiency (Ibarra et al. 2011).While it does appear that there may be some increased pres-sures on food production due to conservation measures, thisdoes not take into account historically degraded agriculturalareas whose long removal from agricultural production hasalso created unacknowledged pressures. The role of invasiveplants such as bracken fern has not been incorporated into thediscussion of how to increase agricultural yields inunderperforming landscapes. It has been shown that farmerawareness of historic anthropogenic degradation is absent,and this is an initial constraining factor in productive restora-tion. In addition, self-imposed conservation policies such ashunting bans have also created a more intense problem withnuisance animals in the limited agricultural efforts in the de-graded areas. Addressing invasive species in the landscape hasalso been approached as primarily a technical issue of theoptimal ways to eradicate the species. We propose a social-ecological approach to agricultural landscape restoration thatbegins with increasing farmer awareness of unobserved andunacknowledged anthropogenic degradation, which couldshift feedback processes leading to a new coupled dynamicresulting in productive restoration. In the particular case of thetwo study communities, restoration could increase agriculturalproduction in areas close to the community, reduce tensionsand pressures over use of the conserved areas, control nui-sance animals, and be a step towards more sustainable liveli-hoods by reducing time spent walking to distant fields andwith health benefits in not having to carry heavy loads longdistances.

Based on the case study in the Chinantla Region, weshowed the potential for collective action on participatory res-toration of invaded bracken fern areas, which is a problem thataffects many other tropical forests in southern Mexico andaround the world. Restoration can be based on existing localknowledge of bracken fern control along with new perspec-tives on managing diverse pathways to annual agriculture,agroforestry, and forest patches for firewood and commercialtimber. Our research suggests that greater attention to modelsfor restoring degraded agricultural areas should become a key

component in proposals for restoring tropical landscapes ingeneral with optimal mixes of land-sharing. The goal of in-creasing food security as part of a sustainable multi-functionallandscape should be addressed in future development re-search, particularly in the context of likely future climatevariability.

Acknowledgments We thank the communities of Santiago Tlatepuscoand San Pedro Tlatepusco for support during fieldwork and to the inter-viewees. Thanks to Fernando Gumeta- Gómez for the cartography.

We thank four anonymous reviewers for their valuable comments toimprove this paper.

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