Search

Mexico aims to develop highly productive and sustainable food systems that ensure national self-sufficiency. This paper employs an integrated land-use modeling tool—the FABLE Calculator—to estimate the degree of policy ambition required for the country to meet mid-century climate, conservation and production goals in the land-use sector. We generate national-level land-use pathways to mid-century in terms of agricultural production, land use change dynamics, greenhouse gas (GHG) emissions, and availability of land supporting biodiversity under varying assumptions of national policy and productivity changes. We estimate the effects of plausible efforts to achieve sustainability in land-use and food systems to 2050 against a business-as-usual benchmark. In the sustainable pathway, assumptions on agricultural land expansion, reforestation, and protected area expansion reflect existing and aspirational Mexican government policies aiming to improve crop yields, livestock productivity with silvopastoral systems, and GHG mitigation goals. We also model diets that evolve toward Mexican dietary guidelines for a healthier consumption of fats and oils as well as a substantial increase in the intake of fruits and vegetables, pulses, nuts, and fish. Results suggest that Mexico can feasibly adopt a sustainable land-use pathway that provides adequate nutrition for the population by 2050, limit agricultural expansion, reduce GHG emissions, and expand forested lands. This type of integrated land-use modeling can help ensure policy coherence in land and food systems across national strategic plans for climate, biodiversity, and agricultural self-sufficiency, each spearheaded by different government agencies. Importantly, a sensitivity analysis highlights the transformative impact that diets have on land-use systems, and as such, dietary transformation should be considered in all climate mitigation plans. [ABSTRACT FROM AUTHOR]

Facing a dramatic depletion of forests in the Viceroyalty of New Spain, throughout the last decades of colonial rule (between the mid-eighteenth and early nineteenth centuries) the Bourbon administration wrote and published a considerable number of laws, reports, surveys, and ordinances on forest management and conservation. In this paper we examine discourses of forest conservation and the measures applied to preserve this critical resource by colonial official and experts. Drawing on forest laws, ordinances, and reports from national archives in Mexico City, we argue that conservation became part of the concepts which defined how forests were conceptualized and managed, but also that conservation was intrinsic to colonial processes of state-making and territorialization. This paper aims to approach Bourbon officials' understanding of conservation as a complex interrelation between renewed discourses of nature and the practices of colonial forest administration through the idea of indeterminacy. Likewise, it sheds light on patterns that have defined the ways in which forest conservation has been constituted in modern Mexico, addressing a little-studied period in forest management in this country. • Forest conservation was contentious questioning the universality of colonial laws. • Conservation became a site of experimentation to know, govern, and produce forests. • Conservation provides insights into the colonial state's territorial actualization. • Colonial forest laws played an important role in defining the context of depletion. [ABSTRACT FROM AUTHOR]

This study develops a novel mathematical modelling framework for biomass combined heat and power systems (CHP) that links biomass and process characteristics to sustainability assessment of the life cycle. A total of twenty-nine indicators for the process (four-indicators), economic (five-indicators), environmental (eight-indicators) and social global (five-indicators) and local (seven-indicators) aspects have been analysed for sustainability. These are technological: biomass throughput, electricity and steam generations and CHP efficiency; economic: internal rate of return, capital, operating and feedstock costs and cost of production; environmental: global warming, fossil, land and water use, acidification, urban smog, eutrophication and ecotoxicity potentials; social (global): labour rights and decent work, health & safety, human rights, governance and community infrastructure; social (local): total forest land, direct/indirect jobs, gender equality and energy-water-sanitation access for communities, from biomass characteristics (carbon and hydrogen contents), energy demands and economic parameters. This paper applies the developed methodology to a case study in Mexico. From 12.47 kt/year forestry residue, 1 MWe is generated with an associated low-pressure steam generation of 50 kt/year, at the cost of production of $0.023/kWh. This makes the energy provision "affordable and clean" for marginalised/poor communities (the UN Sustainable Development Goals, SDG7). Bioenergy can curb > 90% of the greenhouse gas emissions and primary energy use, 6 kt CO2 eq and 74 TJ annually. Bioenergy reduces other environmental impacts considerably, water consumption, acidification and eutrophication by 87–53%, and urban smog and ecotoxicity by 29–18%. Bioenergy can improve all five social themes in the Central American cluster countries. In addition to the SDG7, the forestry-based bioenergy system can also achieve the SDG6: "clean water and sanitation for all". [ABSTRACT FROM AUTHOR]

Copyright of Textual is the property of Universidad Autonoma Chapingo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents a thematic framework that simplifies and explains the complexity of tourist encounters with nature. The research combines qualitative data, derived from questionnaire surveys, in-depth interviews, field journals and personal observations, of wildlife encounters in Spain and Mexico and encounters with tropical forest in Australia. The data reveal that embodied tourists encounter nature in a multisensory manner, although they privilege visual perceptions of the natural world. There are clear differences in the emotional significance of encounters, with visitors negotiating individual yet diverse relations with their surrounding environment, mediated byin situsocial interactions. Wildlife tourists often perform ritualised roles, directed by tour guides, causing some to question the collective performances of prescribed mobilities. Rainforest tourists, by contrast, are more unbounded in their performances. It is suggested that visitors on guided tours should be given time to experience the wonders of the environment at their own pace, facilitating the achievement of ‘higher order’ needs. The theoretical framework presented in the paper facilitates an exploration of the diversity of connections between people and nature and the myriad ways in which such relationships are formed, interpreted and afforded relevance. The framework is not definitive, but context-specific, serving to inform future understanding. [ABSTRACT FROM PUBLISHER]

Copyright of Revista de Antropología Social is the property of Universidad Complutense de Madrid and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of La Granja, de Ciencias de la Vida is the property of Universidad Politecnica Salesiana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Knowledge about palynology in the Heliconia genus basically concerns species from Central and South America, while studies of species in the Mexican Neotropic are limited. Objective: To contribute to the palynological knowledge and understand the morphological interrelation of pollen from the Heliconia genus of the Mexican Neotropic, as part of reproductive biology studies that may contribute in future works of genetic improvement. Methods: The study was conducted in nine species (12 accessions) of Heliconia native to Mexico which are found in the Germplasm Bank of the National Institute of Agricultural and Livestock Forestry Research (INIFAP). Floral pollen was collected in anthesis and stored for 24 h in 2 % glutaraldehyde and 50 % ethanol, then washed in 50 % ethanol and dehydrated in 70, 90 and 100 % alcohol for 30 min. The samples were left to dry at the critical point of the CO2, mounted in aluminum cylinders covered with double conductive adhesive carbon tape and analyzed with a layer of approximately 20 nm gold-palladium. Samples were observed in MEB model TOPCON, SM-510. Results: Pollen measures, 50.22 µm to 70.56 µm, is heteropolar and has an euoblate, suboblate or oblate-spheroidal shape. Distal and proximal faces presented different degrees of convexity; both with micro-echinate or micro-verrucate ornamentation. Morphological characteristics, pollen shape, shape of the proximal and distal faces, as well as ornamentation, showed some homogeneity. However, five groups were formed through the analysis of hierarchical grouping (R² = 0.05). Group I present some micro-perforations in the tectum, high density of micro-echinates and high convexity of the proximal face. In contrast to Group I, Group II has their distal face convex with half density of micro-echinates and a plane-subconvex proximal face. Group III is represented by H. latispatha and group IV is represented by H. librata, both groups have small pollen (for the present study). Although, H. latispatha has a verrucae distal face and a plane proximal face, germinating pore that is distinctively protruding, and H. librata has verrucae in both faces. In group V, H. collinsiana has a distinctively protruding germinating pore and a "corrugated circle-shaped" in the proximal face. Among varieties, H. collinsiana is 10 µm higher than H. collinsiana var. velutina in its equatorial plane. Conclusions: Heterogeneity of characteristics allowed pollen groups to be generated; whilst relatively homogeneous characteristics allowed for recognition of species and varieties within the groups. The morphology of the Heliconia species in Mexico confirms the previously described characteristics; however, additional features such as the presence of micropores and the corrugated circle-shaped in the proximal face stand out. [ABSTRACT FROM AUTHOR]

Reforestation is one of the main actions undertaken to mitigate the effects of climate change. In Mexico, the Federal Government program "Sembrando Vida" (Sowing Life) is currently the most important reforestation effort. It aims to recoup forest cover and achieve food self-sufficiency through the establishment of agroforestry systems. The evaluation of tree survival in reforested areas helps to identify achievements and failures, as well as aspects of the program that require improvement. However, given the magnitude of this program, evaluation using traditional methodologies is labor-intensive and costly. In this context, drones equipped with high-resolution cameras are a promising tool. The objective of this study was to evaluate the feasibility of using drones to monitor tree survival in reforested areas. This study was conducted in 12 randomly chosen plots, benefited by the "Sembrando Vida" program, located on the Purépecha Plateau in the state of Michoacán, in central–western Mexico. Field surveys with GPS were conducted to record the total number of live and dead forest-tree seedlings. Simultaneously, high-resolution images were captured using a DJI Phantom 4 Pro drone equipped with an RGB camera for subsequent visual interpretation in a geographic information system to determine the status of each seedling and calculate the rates of survival. ANOVA was performed to compare the survival calculated using the drone images compared to that recorded in the field. No significant difference was found between survival estimated using the drone and that recorded directly in the field in any of the study plots, although the drone overestimated survival by an average of 6%, mostly due to the presence of dead seedlings that had already lost their foliage and were thus missed when scoring the RGB image. It is therefore concluded that the estimation of survival using drones is a reliable method. For future research, it is recommended to evaluate machine-learning algorithms in terms of detecting both living and dead trees in reforested sites. It is also recommended to use multispectral thermal cameras and LiDAR technology to broaden the knowledge of the different levels of vigor/stress present in the vegetation. [ABSTRACT FROM AUTHOR]

Copyright of Cuadernos de Desarrollo Rural is the property of Pontificia Universidad Javeriana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Mexicana de Economía Agrícola y de los Recursos Naturales is the property of Universidad Autonoma Chapingo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Over the last decade, carbon forestry has grown in Chiapas, where small farmers are increasingly turning to planting carbon-sequestering trees and the carbon market as a new source of income. Using an agrarian political ecology approach, and based on empirical research in a rainforest community in the Lacandon Jungle, I argue that while carbon offset producers continue to have formal land rights, they lose some of the short-term benefits of land in part through the use of land for carbon-sequestering trees but mostly through the preoccupation of labor. The labor requirements for carbon production act as a type of enclosure mechanism that constrains more traditional land uses such as the production of subsistence and annual cash crops. Nevertheless, campesinos continue to participate in carbon forestry as a means to maintain a foothold on their land in the wake of neoliberal agrarian policies that threaten to displace them. Carbon forestry enables campesinos to maintain their land through productive activity, which, though it delivers limited short-term income, allows them to stake claims to land by demonstrating active land use. This paper illustrates the continued relevance of the agrarian question. [ABSTRACT FROM AUTHOR]

Copyright of Revista Chapingo Serie Ciencias Forestales is the property of Universidad Autonoma Chapingo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ecoscience (Ecoscience) is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Shifting cultivation around the Calakmul Biosphere Reserve of Mexico, part of the Mesoamerican Biological Corridor, appears to be intensifying temporally through reductions in crop–fallow cycles, with potential impacts on species diversity in the regenerating forest patches surrounding the reserve. This paper documents the temporal intensity of shifting maize cultivation in the region and links it to the species diversity found in secondary vegetation of different ages following different crop–fallow cycles. It finds that younger secondary growth, which is increasing under intensification, has less diversity in species composition. Simultaneously, the concentration of cultivation practices appears to foster more patches in older and more species-diverse vegetation. The implications for the preservation of the region’s forest remain uncertain, however, given the spatial concentration of open lands along two key axes, one which dissects the reserve. [ABSTRACT FROM AUTHOR]

Climate change is increasing the intensity of extreme weather events. Mexico is particularly prone to suffer at least two different types of these events: droughts and hurricanes. This paper focuses on the effects of an extended drought on the Mexican economy. Through a computable general equilibrium model, we simulate the impact of a drought that affects primarily agriculture, livestock, forestry, and hydropower generation. We look at the effects on the overall economy. We then simulate the effects of several adaptation strategies in (chiefly) the agricultural, forestry, and power sectors, and we arrive at some tentative yet significant conclusions. We find that the effects of such an event vary substantially by sector with moderate to severe overall impacts. Furthermore, we find that adaptation policies can only effect modest changes to the economic losses to be suffered. [ABSTRACT FROM AUTHOR]

Abstract: This article proposes a multi-dimensional framework for understanding the development and effectiveness of Payments for Ecosystem Services (PES) schemes, framed around the notions of institutional design, performance and interplay. The framework is applied in the context of Mexico''s Programme of Payments for Carbon, Biodiversity and Agro-forestry Services (PSA-CABSA), with an emphasis on its carbon component. The analysis shows that PSA-CABSA was promoted by civil society and its rules have been subject to continuous modifications over time. In the case of the carbon component, changes have been due to an original misunderstanding of how carbon projects should be designed, implemented, and carbon traded in actual markets. From a performance point of view, the paper shows that the programme has been well received by rural communities, and carbon payments have contributed to increase household income and to enhance forest management practices and organisational skills. The paper also highlights sources of institutional interplay with local institutions and international climate policy, and it reveals the importance of capacity and scale issues in securing an effective and fair implementation of PES. The conclusion provides some policy recommendations for the future development of PES initiatives in Mexico and elsewhere. [Copyright &y& Elsevier]

Diversification in resource management can serve as a strategy to increase both economic well-being and environmental sustain- ability in rural communities, especially in tropical forested regions. This paper documents and analyzes the recent and rapid regional commercialization of small diameter, lesser-known tropical hardwood species as polewood in Quintana Roo, Mexico, presenting the promises and perils for sustainable management and resource diversification in the context of Mexican economic development and community forestry. We present data from interviews with local farmers and forestry officials involved in community management of timber resources to reveal baseline information regarding the use and management of polewood, locally called palizada. We found the same permitting system used for high-value timber was implemented for polewood without recognizing the complex ecological characteristics of polewood and the different metrics by which polewood and high-value timber are bought and sold. These factors, coupled with an unstable market for this new forest product and potential for overexploitation, present a difficult situation for the sustainable management of polewood. We conclude that incorporating local ecological knowledge in devising polewood management strategies can strengthen local governance and is an essential aspect of managing this emerging market of forest products. [ABSTRACT FROM AUTHOR]

ABSTRACTThis paper discusses the gain in efficiency from including deforestation risk as a targeting criterion in payments for environmental services (PES) programs. We contrast two payment schemes that we simulate using data from Mexican common property forests: a flat payment scheme with a cap on allowable hectares per enrollee, similar to the program implemented in many countries, and a payment that takes deforestation risk and heterogeneity in land productivity into account. We simulate the latter strategy both with and without a budget constraint. Using observed past deforestation, we find that while risk-targeted payments are far more efficient, capped flat payments are more egalitarian. We also consider the characteristics of communities receiving payments from both programs. We find that the risk-weighted scheme results in more payments to poor communities, and that these payments are more efficient than those made to non-poor ejidos. Finally, we show that the risk of deforestation can be predicted quite precisely with indicators that are easily observable and that cannot be manipulated by the community. [ABSTRACT FROM AUTHOR]

Copyright of Biotropica is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Most accounts of the effect of the global marketplace on deforestation in Africa, Asia, and Latin America emphasize the demand for timber used in industrial processes and the conversion of tropical forests to pastures for beef cattle. In recent years, numerous scholars and policymakers have suggested that developing a market for non-timber forest products (NTFPs) might slow the pace of habitat destruction. Although increased demand for NTFPs rarely results in massive deforestation, the depletion of the raw materials needed to make particular products is common. Many rural households in the Mexican state of Oaxaca have prospered over the past three decades through the sale of brightly-painted, whimsical wood carvings ( alebrijes) to international tourists and the owners of ethnic arts shops in the United States, Canada, and Europe. This paper examines a promising project aimed at providing Oaxacan alebrije-makers with a reliable, legal, and sustainable supply of wood. The ecologists, artisans, merchants, and forest owners involved in the project face formidable obstacles. Gaining permission to harvest wood from land belonging to Oaxacan communities requires the negotiation of a complex social, legal, economic, and political landscape. Artisans’ decisions about where to obtain wood rest largely on price, quality, and reliability of the supplier; they are willing to pay a premium for ecologically sustainable wood only if the additional cost can be passed on to consumers. Nonetheless, a group of carvers has begun to buy sustainably harvested wood. This arrangement has economic advantages for both the alebrije-makers and the owners of the forests where the wood is produced. [ABSTRACT FROM AUTHOR]

Copyright of Biotropica is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract. In this paper we analyse six communities with seven Mimosa species in the Tehuacán-Cuicatlán valley, Mexico. All species are endemic to Mexico and four are endemic to the valley. Mimosa species are found in (1) the 'matorral xerófilo' (arid tropical scrub): Mimosa calcicola, M. lacerata, M. luisana, M. polyantha and M. purpusii, and (2) the 'selva baja caducifolia' (tropical deciduous forest): M. adenantheroides, Mimosa texana var. filipes. Most of them occur in similar soil environments, while M. polyantha and M. calcicola establish in particular soil conditions and only M. luisana establishes in two different sites showing a wider range of adaptation to soil characteristics. The communities studied include 24 plant families, 51 genera and ca. 70 species (5% of the total flora estimated in the valley). Heterogeneity was found among the communities. Our results point to the replacement of 'matorral xerófilo' and 'selva baja caducifolia' by 'matorral espinoso' (thorny scrub). Thorny species (e.g. Acacia cochliacantha, Mimosa spp.) are becoming the dominant/codominant elements in the communities. Within the communities, Mimosa species have a significant influence on soil pH, organic matter and electrical conductivity values. These species contribute to ameliorate soil nutrient conditions (OM, N[sub tot], P, Ca, Mg, Na and K contents) as well as other environmental factors (e.g. temperature, shade) under their canopy in degraded plant communities and may serve as 'resource islands'. [ABSTRACT FROM AUTHOR]

Copyright of Biotropica is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper describes structural change and damage to the natural tree vegetation in the Dr Alfredo Barrera Marín Botanical Garden, following Hurricane Gilbert in September, 1988. Posthurricane data were compared with pre-hurricane data from the same plots, focusing mainly on composition and structure. Near complete defoliation of trees and plants of the understorey occurred and average foliage loss was estimated to be 4.5 t/ha. The density of trees decreased by 33%, and the basal area decreased by 12%. Small diameter trees accounted for the great majority of losses and trees in the largest diameter classes survived best. The average height of trees in the lower canopy decreased by 6% and for those in the upper canopy by 9%. The frequency of understorey plants decreased by 51% and their cover decreased by 70%. Floristic richness decreased only slightly after the hurricane. [ABSTRACT FROM AUTHOR]

Under certain circumstances, land titling, property regime changes, and land‐use conversions yield substantial profits. Yet few people possess the wealth, knowledge, and networks to benefit from these procedures. In the Yucatán Peninsula, a region recently targeted as a prominent investment location by the Mexican national government (mainly with the "Tren Maya" megaproject) and the private capital, forestlands collectively owned as ejidos by Mayan peasants are on the trend to complete privatization. Against the arguments of neo‐institutional economists that in the 1990s promoted legal reforms and justified land‐titling programmes worldwide to make available credit for uncapitalized peasants, individual land titling of commonly held lands in Mexico increased the overall economic value of the land, but not the investment in economic activities related to farmland and indigenous communities. Instead, those policies enabled land grabbing, dispossession, and urbanization. In this article, I describe recent private‐led initiatives of ejido land titling that have redefined agricultural land's uses, meanings, and values for capitalist accumulation. In doing so, I explain how and why Mayan ejidatarios have been excluded from the monetary benefits of land titling, a top‐bottom dispossession process only accomplished through shadow procedures and former privatization of ejidos' common lands. [ABSTRACT FROM AUTHOR]

This paper presents new equations for estimating above-ground biomass (AGB) and biomass components of seventeen forest species in the temperate forests of northwestern Mexico. A data set corresponding to 1336 destructively sampled oak and pine trees was used to fit the models. The generalized method of moments was used to simultaneously fit systems of equations for biomass components and AGB, to ensure additivity. In addition, the carbon content of each tree component was calculated by the dry combustion method, in a TOC analyser. The results of cross-validation indicated that the fitted equations accounted for on average 91%, 82%, 83% and 76% of the observed variance in stem wood and stem bark, branch and foliage biomass, respectively, whereas the total AGB equations explained on average 93% of the total observed variance in AGB. The inclusion of total height (h) or diameter at breast height2 x total height (d2h) as a predictor in the d-only based equations systems slightly improved estimates for stem wood, stem bark and total above-ground biomass, and greatly improved the estimates produced by the branch and foliage biomass equations. The predictive power of the proposed equations is higher than that of existing models for the study area. The fitted equations were used to estimate stand level AGB stocks from data on growing stock in 429 permanent sampling plots. Three machine-learning techniques were used to model the estimated stand level AGB and carbon contents; the selected models were used to map the AGB and carbon distributions in the study area, for which mean values of respectively 129.84 Mg ha-1 and 63.80 Mg ha-1 were obtained. [ABSTRACT FROM AUTHOR]

Countries often lack methods for rapidly, but robustly determining greenhouse gas (GHG) mitigation actions and their impacts comprehensively in the land use sector to support commitments to the Paris Agreement. We present rapid assessment methods based on easily available spatial data and adoption costs for mitigation related to crops, livestock and forestry to identify priority locations and actions. Applying the methods for the case of Mexico, we found a national mitigation potential of 87.88 million tons (Mt) CO2eq yr−1, comprising 7.91, 7.66 and 72.31 Mt CO2eq yr−1 from crops, livestock and forestry/agro-forestry, respectively. At the state level, mitigation potentials were highest in Chiapas (13 Mt CO2eq) followed by Campeche (8 Mt CO2eq). Eleven states had a land use mitigation potential between 2.5 to 6.5 Mt CO2eq, while other states had mitigation potentials of less than 2 Mt CO2eq. Mitigation options for crops and livestock could reduce 60% and 6% of the respective emissions. Mitigation options for forestry could reduce emissions by half. If properly implemented, mitigation potentials on cropland can be realized with net benefits, compared to livestock and forestry options, which involve net costs. The method supports science-based priority setting of mitigation actions by location and subsector and should help inform future policy and implementation of countries' nationally determined contributions. [ABSTRACT FROM AUTHOR]

In this paper we report new localities for Abronia oaxacae and Tantalophis discolor in a pine forest with intense management in San Pedro El Alto locality, municipality Zimatlán, in the state of Oaxaca, southwestern Mexico. These new localities extends the known range of both species. [ABSTRACT FROM AUTHOR]

When compared with other stated preference valuation methodologies, deliberative valuation gives participants more time and information, potentially resulting in more valid and reliable estimations and higher participant confidence. However, it also has weaknesses, such as small sample sizes, lower participant diversity, and high costs. This paper proses a minimalist framework for deliberation that increases sample size and lowers the cost per participant through short, structured deliberative sessions and the use of deliberative sub-groups. A case study was conducted with 192 landholders in south-eastern Mexico, examining how participants' perceptions of benefits from communal forest lands would impact their willingness to accept (WTA) comparatively lower payments to participate in a Payment for Ecosystem Services (PES) program. The results suggest that a majority of landholders would accept a lower payment level to participate in a PES program over a degradative alternative, with 45.5% of participants surveyed willing to accept a 45% reduction in payments to participate in the PES program. The minimalist framework had an impact on participants' rate of acceptance, with a 13.8% increase in the percentage of participants willing to accept the PES offer post-deliberation. The impact on participant confidence was stronger, with a 31.2% increase in the percentage of participants expressing confidence in their choice after deliberations. [ABSTRACT FROM AUTHOR]

The Southwest region of the State of Mexico (PSEM as it stands in Spanish) is located in the so called Mexican Transition Mountainous Zone. The forest communities that prevail in this area are pine trees forests (Pinus spp.), oak trees forests (Quercus spp.), mixed ones, mountainous cloud forest and tropical deciduous forest, which are being modified due to the influence of human processes. This research paper establishes a methodology to analyze the changes on the land cover of the PSEM which took place from 1989 to 2009 using a technique of image satellite interpretation (Landsat TM), as well as the use of the maximum authenticity algorithm which leads towards the implementation of soil and vegetation maps whose main purpose is to obtain information on the validity of these study cases. Overlapping those maps, it is possible to come up with a matrix of changes to check annual modifications on the land cover, and based on it the changes rates can be measured. From data obtained through this research, it can be stated that the land cover of this forest has considerably decreased because 19 262 ha disappeared and were taken up by water supplies (105 ha), farming lands (19 113 ha), human settlements (39 ha) and technical and controlled agriculture (5 ha). It can be summed up that this deforestation mainly comes as a result of the practice of agriculture and livestock activities indeed. [ABSTRACT FROM AUTHOR]

Woody flora of cloud forest (BMM) in Tamaulipas has different taxa with respect to other BMM in Mexico. Consequently, wood anatomical characters of its species can also express this variability, related to environment and the linages to which they belong. In this paper, wood anatomy of 12 species growing in of the BMM at "El Cielo" Biosphere reserve in Tamaulipas, Mexico was described. Unlike other Mexican BMM, results showed a positive trend with respect to the presence of conspicuous growth rings. This character seems related to the geographical position of this BMM in Mexico. Other characters such as diffuse porosity, tangential vessels diameter < 100 µm, vessel elements with helical thickenings and length >350 µm, fibers lengths > 900 µm, and scarce axial parenchyma, are common features in the species studied. Some anatomical characters of taxa were compared with related groups at the genus or family level. [ABSTRACT FROM AUTHOR]

Mesquite is one of the most important forest resources in northern Mexico, constituting an important part of the national flora and its great importance to the inhabitants of the arid and semiarid regions. This paper shows a volumen and wood weight table obtained in m³ which can be used in the área of influence. This technique was based on dimensional analysis, measuring the tres readily available, which enables farmers, foresters and institutions, rely on production parametersand volumen of timber (wood) for the rational and sustainable use of natural populations of mesquite, in turn providing protection and conservation of the environment. The evaluation was conducted in Ejido San Antonio de la Sierrecilla, municipality of Mazapil, Zacatecas. The largest diameter was measured on crown and total height in cm, destructive sampling was carried out in 39 trees, and volume and weight of branches were determined. In regression analysis polynomial model was used resulting in timber volumen (m³)=2,341E-6X²-0,0012X+0,1803 and determination of weight (kg)=0,001X2- 0,556X+81,909*D with 95% reliability. [ABSTRACT FROM AUTHOR]

Recent studies have suggested that climatic variations may have implications on ecosystem biogeography. Dendrochronological techniques constitute a useful tool to analyze relationships tree growth-climate. Ring widths usually are standardized before the analysis in order to remove unwanted bias due to individual growth related to stem size and age. This approach produces rings widths indices while retaining climatic signals that are in common among trees into a single chronology. However, in dendroclimatology few papers show their sensitive capacity. As a result its use could be becomes routine practice without considering their implications. The aim of this work was to assess the climate sensitivity responses of three chronologies indexes of Pinus cooperi: Standard (Sd), Residual (Rd), and Arstan. Such series were correlated with historical records of precipitation, temperature and two index El Niño-Southern Oscillation ENSO (Niño3 and MEI).The three chronologies showed similar trends during previous growing months (August to December). Nevertheless, Rd was better associated with current growing months, but showed weaker correlation with ENSO. Comparatively Sd and Ar demonstrated stronger sensibility to large-scale climatic patterns in previous growing months. It is concluded that appropriate selection of dendrochronology index is important, indicating repercussions on climatic scenarios. Neither should be considered substitutes for each other. Combining them with complementary tools would improve the sensitivity capacity of ecological processes in the forest. [ABSTRACT FROM AUTHOR]

Non Timber Forest Products (NTFP) contribute to the food security of forest communities. Around 1000 of those are used in Mexico, but little information is available on local knowledge and women's roles in NTFP management. This paper pursues three objectives: to describe the distribution, light and soil conditions of a NTFP called "poleo" Satureja macrostema (Benth.) Briq.; to document local knowledge on this plant; to analyze gender differences in terms of access, use and trade. Research was conducted in San Miguel Mixtepec, a Zapotec community of the Central Valleys of Oaxaca. Methods include soil and canopy analysis, participant observation, interviews and workshops. Poleo grows under a closed canopy, in slightly acid, organically rich soils. Local knowledge on the plant's reproductive process contributes to its permanence. The plant is used for community rituals, as ornament, food and medicine. Men predominate in the first two uses and women in the remaining ones. Trading activities are female-dominated, mostly by 'widows' (adult women with children and no partner). The plant is informally traded in regional markets at very low prices. However, its barter or sale contributes to diversify local diets and is a good example of women's subsistence activities in the forest communities of Mexico. [ABSTRACT FROM AUTHOR]

In this paper, three equations were generated to estimate the normal diameter, height and total volume from stump diameter for Quercus laurina stands in Ixtlan de Juarez, Oaxaca, with a sample of 54 trees. Linear and nonlinear models were adjusted to the database to obtain the most reliable equation to the functional relationship: (a) normal diameter - stump diameter, (b) total height - stump diameter and (c) total volume-stump diameter. The criteria for defining the adjustment in all three cases was based on: normal and adjusted coefficient of determination, mean square error, P-value, coefficient of variation, and sum and dispersion of residuals against predicted values. The model with the highest goodness of fit for the estimated normal diameter based on the diameter of the stump was the simple linear regression model, and in the other two cases, it was the potential model. With these equations, it is possible to accurately estimate the dependent variables values and evaluate different scenarios in areas affected by natural or anthropogenic phenomena. [ABSTRACT FROM AUTHOR]

This paper seeks to show the deforestation rate in Mexico based on land use and vegetation changes data from 1976 to 2007 using the official data published by INEGI. The results of the National Forest Inventory for 2000 were added to make a cut and the process was analyzed in two stages from 1976 to 2000 and from 2000 to 2007. Moreover, a polygon level analysis was carried out over the forest with secondary vegetation to know if they are coming from a recovery process or from a degradation process. The results show that the change rates are lower in the 2000-2007 than the 1976-2000 periods, but the annual loss of forest are around the 500 000 ha. For the complete period it was found a forest annual loss of 534 707 ha. The deforestation official data are sub valued since 2006 because they discount the 100% of secondary vegetation, when the real amount of recovery process is over 10% to 13%. The deforestation official data were recalculated from 2006 on, and the new results match with the amount of 500 000 ha per year. The principal use for the deforested areas is still the rainfed agriculture. [ABSTRACT FROM AUTHOR]

Coarse woody debris (CWD) is an important component in the structure and function of southwestern mixed-conifer forest ecosystems. However, fire suppression and exclusion policies have changed the structure and fuel loads, including CWD, during the last 130 years. Consequently, managers are faced with the threat of stand replacement fires over large spatial areas and are seeking solutions to these challenges using silvicultural techniques. Our paper presents CWD characteristics based on 100-h and 1000-h time-lag fuels before (2006) and after (2016) silvicultural treatments including harvest, prescribed fire, and no treatment (control) on mixed-conifer forests in southcentral New Mexico, USA. Results indicated late-season broadcast burns characterized by mild fire behavior reduced 100-h CWD (Mg ha−1) and potentially 1000-h CWD. However, because control sites also saw reduced 1000-h CWD, this result was confounded. Harvest treatments maintained 1000-h CWD, which could be considered a compensatory response given the decrease in CWD on adjacent control sites over the same time period. This was supported by an increase in 1000-h logs per 75 m transect on harvest sites as compared to control sites. Silvicultural prescriptions including prescribed fire are useful tools to increase or decrease CWD to meet management objectives. [ABSTRACT FROM AUTHOR]

This paper analyze, from a historical perspective, organizational processes and how local institutions use their natural resources in the context of regional dynamics and environmental policies that seek to conserve biodiversity, and also stress the importance of protected natural areas. We refer to the relationship between the protected area, The Sian Ka'an Biosphere Reserve and local fishing and forestry. The results show that in Sian Ka'an Biosphere organizational processes occurred prior to the establishment of the reserve. These processes helped to support established local institutions that had properly managed their natural resources. Therefore, a successful application of environmental conservation policies in protected natural areas should keep in mind historical and cultural processes of local players. [ABSTRACT FROM AUTHOR]

This paper analyzes Mexico's state-directed common property system from the point of view of Elinor Ostrom's design principles, her ideas of levels of institutional choice (constitutional, collective, and operational) and the issue of both origins and changes in institutional supply. The historical evolution of common property institutions, with special reference to forest management communities suggests that the Mexican case requires an extension of common property design principles to take into account that local rule-making and a national regulatory apparatus can be optimally combined and that markets can be an important factor in success on the commons. [ABSTRACT FROM AUTHOR]

Land use land cover change studies have traditionally focused on deforestation processes and their associated drivers, while ignoring or assuming that reforestation processes were the reverse. However, recognition that regrowth processes are equally as complex and important as deforestation processes and play an important role in the large scale functions of tropical forests has led to a growing research interest in forest transitions. In this paper we make a contribution to the understanding of the complex dynamics involved in reforestation, by addressing the question: What are the potential drivers of forest transition in the municipalities of Tzucacab, Peto, and Oxkutzcab in the state of Yucatán, México? Analysis of satellite imagery from the region was used to highlight changes in vegetation between the image dates of 1988, 1994, and 2003. Government census data from 1980, 1990, and 2000 were used to assess the population dynamics and economic trends. In 2005 municipal officials and local market venders were interviewed regarding local land uses. The integration of the results from these analyses suggest that the trend in deforestation between 1988 and 1994 followed by forest regrowth between 1994 and 2003 in all three municipalities can be associated with national government policies, economic development and activities, changes in the spatial hierarchy of the market system, and out-migration. [ABSTRACT FROM AUTHOR]

Tropical montane cloud forests (TMCF) are among the most threatened ecosystems globally in spite of their high strategic value for sustainable development due to the key role played by these forests in hydrological cycle maintenance and as reservoirs of endemic biodiversity. Resources for effective conservation and management programs are rarely sufficient, and criteria must be applied to prioritise TMCF for conservation action. This paper reports a priority analysis of the 13 main regions of TMCF distribution in Mexico, based on four criteria: (1) forest quality, (2) threats to forest permanence, (3) threats to forest integrity, and (4) opportunities for conservation. Due to the diverse socio-environmental conditions of the local communities living in Mexican TMCF regions, their associated social characteristics were also evaluated to provide a background for the planning of conservation actions. A set of indicators was defined for the measurement of each criterion. To assign priority values for subregions within each main region, an international team of 40 participants evaluated all the indicators using multicriteria decision-making analysis. This procedure enabled the identification of 15 subregions of critical priority, 17 of high priority, and 10 of medium priority; three more were not analysed due to lack of information. The evaluation revealed a number of subjects that had hitherto been undetected and that may prove useful for prioritisation efforts in other regions where TMCF is similarly documented and faces equally severe threats. Based on this analysis, key recommendations are outlined to advance conservation objectives in those TMCF areas that are subjected to high pressure on forest resources. [Copyright &y& Elsevier]

Abstract: In this paper we present the Mexican inventory of greenhouse gas (GHG) emissions from the land-use sector. It involved integration of forest inventory, land-use and soil data in a GIS to estimate the net flux of GHG between 1993 and 2002. The net GHG flux of 86.9 (±34.4%)TgCO2 y−1 resulted from the balance of emissions of 64.5 (±12%)TgCO2 y−1 from biomass loss, 4.9 (±259%)TgCO2 y−1 from managed forests, and 30.3 (±106%)TgCO2 y−1 from mineral soils, and the removals of 12.9 (±36%)TgCO2 y−1 in abandoned lands. Main sources of uncertainty include lack of integrated soil and biomass data and the impact of the various management practices on biomass. Key factors are identified to improve GHG inventories and to reduce uncertainty. [ABSTRACT FROM AUTHOR]

This paper describes a user-friendly computer application developed for forest management planning in El Salto, Durango (Mexico). The computer program BWINPro7 version El Salto allows for forest growth and predicts future stand development. It represents an easy tool that can be used by forest managers and owners of forest lands in the decision-making process. The program incorporates individual tree growth models developed for most pine and oak species during recent years in mixed and uneven-aged forests in the north-eastern region of Mexico. Specifically, the models that were incorporated into the program BWINPro7 are: (1) models to estimate crown width and the height to the live crown base, (2) individual tree basal area and height growth models, and (3) a model to predict individual tree mortality. In addition, the simulator can be used in permanent sample plots to describe stand spatial structure, and to prescribe thinning and timber harvest at industrial scale. [ABSTRACT FROM AUTHOR]

Abstract: This paper shows the results of an assessment on the current extent of Neotropical dry forests based on a supervised classification of MODIS surface reflectance imagery at 500-m resolution. Our findings show that tropical dry forests extend for 519,597km2 across North and South America. Mexico, Brazil and Bolivia harbor the largest and best-preserved dry forest fragments. Mexico contains the largest extent at 181,461km2 (38% of the total), although it remains poorly represented under protected areas. On the other hand, Brazil and Bolivia contain the largest proportion of protected tropical dry forests and the largest extent in continuous forest fragments. We found that five single ecoregions account for more than half of the tropical dry forests in the Americas (continental and insular) and these ecoregions are: the Chiquitano dry forests, located in Bolivia and Brazil (27.5%), the Atlantic dry forests (10.2%), the Sinaloan dry forests in Mexico (9.7%), the Cuban dry forests (7.1%) and the Bajio dry forests in Mexico (7%). Chiquitano dry forests alone contain 142,941km2 of dry forests. Of the approximately 23,000km2 of dry forest under legal protection, 15,000km2 are located in just two countries, Bolivia and Brazil. In fact, Bolivia protects 10,609km2 of dry forests, where 7600km2 are located within the Chiquitano dry forest ecoregion and protected by a single park. Low extent and high fragmentation of dry forests in countries like Guatemala, Nicaragua, Ecuador, Costa Rica and Peru means that these forests are at a higher risk from human disturbance and deforestation. [Copyright &y& Elsevier]

Abstract: Ambiguity between forest types on remote-sensing imagery is a major cause of errors found in accuracy assessments of forest inventory maps. This paper presents a methodology, based on forest plot inventory, ground measurements and simulated imagery, for systematically quantifying these ambiguities in the sense of the minimum distance (MD), maximum likelihood (ML), and frequency-based (FB) classifiers. The method is tested with multi-spectral IKONOS images acquired on areas containing six major communities (oak, pine, fir, primary and secondary high tropical forests, and avocado plantation) of the National Forest Inventory (NFI) map in Mexico. A structural record of the canopy and optical measurements (leaf area index and soil reflectance) were performed on one plot of each class. Intra-class signal variation was modelled using the Discrete Anisotropic Radiative Transfer (DART) simulator of remote-sensing images. Atmospheric conditions were inferred from ground measurements on reference surfaces and leaf optical properties of each forest type were derived from the IKONOS forest signal. Next, all forest types were simulated, using a common environmental configuration, in order to quantify similarity among all forest types, according to MD, ML and FB classifiers. Classes were considered ambiguous when their dissimilarity was smaller than intra-class signal variation. DART proved useful in approximating the pixel value distribution and the ambiguity pattern measured on real forest imagery. In the case study, the oak forest and the secondary tropical forest were both distinguishable from all other classes using an MD classifier in a 25m window size, whereas pine and primary tropical forests were ambiguous with three other classes using MD. By contrast, only two pairs of classes were found ambiguous for the ML classifier and only one for the FB classifier in that same window size. The avocado plantation was confounded with the primary tropical forest for all classifiers, presumably because the reflectance of both types of forest is governed by a deep canopy and a similar shadow area. We confronted the results of this study with the confusion matrix from the accuracy assessment of the NFI map. An asset of this model-based method is its applicability to a variety of sensor types, eco-zones and class definitions. [Copyright &y& Elsevier]