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This paper reviews and discusses the main features of biological invasion by plants and the assisted migration theory referencing a critical common factor--belowground ecology. The risk of a plant becoming invasive and the potential failure of assisted migration programs depend on the presence or absence of soil microorganisms that regulate key ecosystem processes and mitigate adverse environmental conditions. This biotic interaction should be considered in the selection of sites for afforestation programs since it is as important as temperature and precipitation regarding conservation decisions, and assisted migration practices in response to climate change. Fungal species should be determined and included in climate change mitigation programs to avoid disease outbreaks and ensure the presence of beneficial mutualistic species in sites selected for assisted migration. Plants considered for assisted migration should pose a low risk of becoming invasive for having establishment difficulties per se. However, the real threat is that they may displace other species, introduce pathogens, or trigger disease outbreaks in introduction sites that nullify assisted migration efforts. Key words: climate change, environmental decision-making,, 1. Introduction While we know the impacts of climate change on temperate forest individuals, populations, and communities, we lack a baseline for understanding the role of microorganisms in successful assisted [...]

The conceptual framework of socio-ecological systems (SES) has been used to redirect resource management practices towards more sustainable scenarios. Utilizing surveys conducted with 350 producers of a silvopastoral cattle network in southern Mexico, the structure and interactions of cattle SES were characterized. Furthermore, based on information derived from a workshop with producers, the framework was operationalized through variables representing action situations and generating outcomes in terms of management, organizational issues, and ecosystem services. This participatory exercise allowed for the identification of locally relevant sustainability components and ranges that can be generalized to other similar SES in Latin America, specific socio-ecological challenges, and potential actions leading to maximizing the sustainability of silvopastoral ranches in the tropics. Challenges include an excessive number of intermediaries, labor conditions accentuating poverty, marketing chains inaccessible to small scale producers, and low diversification. These issues can be addressed within the cattle SES through technical and financial support from involved governmental institutions and strengthening the local governance system. This work bridges gaps in cattle research by highlighting that sustainable intensification through the establishment of silvopastoral systems is possible within specific ranges, and sustainability can be defined, understood, and built by producers from the territories. [ABSTRACT FROM AUTHOR]

Climate change has profound impacts on ecosystems, and one critical aspect is its effect on seed germination, a crucial stage in plant life cycles. Various studies have explored the responses of plant species to rising temperatures, and there is now a pressing need to integrate this wealth of information into a coherent framework. The aim of this study was to survey literature about seed traits and thence to evaluate germination responses to climate change and to propose functional groups for germination. Increased temperature affects seed traits, particularly germinability. Many species show increased germination percentages in warmer temperatures, although the extent varies among species and temperature ranges. Some maintain a consistent percentage, whereas others reduce it to retain seeds in the seed bank. Temperature changes also affect the timing and season of germination, with some species accelerating germination, others delaying it, thereby influencing competition and exposure to adverse conditions. Shifts in temperature can alter seed requirements, affecting responses to temperature, humidity, light, chemical stimuli, and dormancy. Modifications in germination have profound effects on seed bank and seedling bank dynamics, affecting plant populations and ecological community resilience. Changes in germination can disrupt competitive dynamics, favoring some over others, altering community composition, and potentially impairing ecosystem functionality. Germination niche, germination potential, and germination phenology are fundamental concepts in the evaluation of climate change's implications for germination. [ABSTRACT FROM AUTHOR]

Vegetation-soil systems differentially influence the ecosystem processes related to the carbon cycle, particularly when one tree species is dominant over wide geographic regions that are undergoing climate change. The objective of this study was to quantify the stocks of ecosystem carbon in three vegetation-soil systems along a highland elevational gradient in central Mexico. The vegetation-soil systems, from lower to higher elevation, were dominated by Alnus jorullensis Kunth, Abies religiosa (Kunth) Schltdl. & Cham., and Pinus hartwegii Lindl., respectively. Above- and below-ground tree biomass was determined in each system, along with the litter, coarse woody material, roots, and litterfall. The A. religiosa system had the greatest stock of aboveground biomass carbon (216 [+ or -] 31 Mg C x [ha.sup.-1]). The A. jorullensis system had the greatest production of litterfall (3.1 [+ or -] 0.08 Mg x [ha.sup.-1] x [year.sup.-1]); however, the carbon content of this litter layer (1.2 [+ or -] 0.32 Mg C x [ha.sup.-1]) was lower than that of P. hartwegii (10.1 [+ or -] 0.28 Mg C x [ha.sup.-1]). Thus, the litter layer in the A. jorullensis system had markedly the shortest residence time (8 years), suggesting high rates of litter decomposition. The soil carbon stock (at soil depth of 1 m) was greater in A. jorullensis (189 Mg C x [ha.sup.-1]) and P. hartwegii (137 Mg C x [ha.sup.-1]) than in A. religiosa (68 Mg C x [ha.sup.-1]). The A. religiosa and A. jorullensis systems had the highest and lowest total ecosystem C content (301 and 228 Mg C x [ha.sup.-1], respectively). Upward migration of the A. religiosa system in response to global climate change, however, could cause losses by 2030 of 187 Mg C x [ha.sup.-1] associated with aboveground biomass. Key words: biomass and carbon stocks, elevational gradient, vegetation-soil systems, temperate forest. Les systemes que forment le sol et la vegetation influencent differemment les processus de l'ecosysteme relies au cycle du carbone, particulierement lorsqu'une espece d'arbre domine de vastes etendues geographiques soumises aux changements climatiques. L'objectif de cette etude consistait a quantifier les stocks de carbone de l'ecosysteme dans trois systemes solvegetation le long d'un gradient d'elevation sur les hautes terres dans le centre du Mexique. Les systemes sol-vegetation, de la plus basse a la plus haute elevation, etaient domines respectivement par Alnus jorullensis Kunth, Abies religiosa (Kunth) Schltdl. & Cham. et Pinus hartwegii Lindl. La biomasse aerienne et souterraine des arbres a ete determinee dans chaque systeme, ainsi que la litiere, les debris ligneux grossiers, les racines et la chute de litiere. Le systeme associe a A. religiosa avait le plus important stock de carbone (216 [+ or -] 31 Mg C x [ha.sup.-1]) issu de la biomasse aerienne. Le systeme associe a A. jorullensis avait la plus forte production de chute de litiere (3,1 [+ or -] 0,08 Mg x [ha.sup.-1] x [an.sup.-1]). Cependant, la teneur en carbone de cette couche de litiere (1,2 [+ or -] 0,32 Mg C x [ha.sup.-1]) etait plus faible que celle de P. hartwegii (10,1 [+ or -]0,28 Mg C x [ha.sup.-1]). Par consequent, la couche de litiere du systeme associe a A. jorullensis avait le temps de residence nettement le plus court (8 ans), ce qui correspond a un taux eleve de decomposition. Le stock de carbone dans le sol (jusqu'a une profondeur de 1 m) etait plus eleve dans les systemes associes a A. jorullensis (189 Mg C x [ha.sup.-1]) et P. hartwegii (137 Mg C x [ha.sup.-1]) que dans le systeme associe a A. religiosa (68 Mg C x [ha.sup.-1]). Les systemes associes a A. religiosa et A. jorullensis avaient la teneur en C total de l'ecosysteme respectivement la plus elevee et la plus faible (301 et 228 Mg C x [ha.sup.-1]). Cependant, la migration vers le haut du systeme associe a A. religiosa en reaction aux changements climatiques planetaires pourrait vers 2030 entrainer des pertes de 187 Mg C x [ha.sup.-1] associees a la biomasse aerienne. [Traduit par la Redaction] Mots-cles : biomasse et stocks de carbone, gradient d'elevation, systemes sol-vegetation, foret temperee., 1. Introduction The effect of plant species on ecosystem processes depends on their physiology and ecology and their interaction with climate and soil (Binkley 1995; Chapin et al. 2011; Augusto [...]

Modern pollen rains have demonstrated that human legacies represent crucial information on the performance of strategies for biological conservation. However, the potential use of pollen rains in aspects related to human disturbance and other cultural processes remains scarcely explored in forest patches of tropical mountain environments. Our study offers an ecological model for stratifying management intensities using moss polster contents in three patches of humid tropical mountain forests from eastern Mexico. Moss polsters were collected at 48 sites between ca. 1600 and 2000 m asl in three Mexican tropical montane cloud forests. Beta diversity, Shannon, and Jaccard indices were calculated for each location. Deciphering palynological data, historical documents, and diversity indicators, we found that the most disturbed patches had the lowest values in the Shannon index (abundance data) and beta diversity (incidence and abundance data) due to intensive agriculture over the last 20 years at least. On the other hand, we found that lower-elevation gradients with a high degree of management intensity and geographical affinity expressed greater similarity according to the Jaccard index for unseen shared species. In contrast, shade-tolerant plants and some hygrophilous trees within the old-growth forest determined the species turnover among higher-elevation gradients in conserved areas. For these reasons, our findings suggest that moss polster contents capture reliable sources of pollen rains around 20 years, as it was once mentioned in the palynological literature. We conclude that pollen rains and management intensity are comparable between ecosystems in long-term approaches and historical legacies. [ABSTRACT FROM AUTHOR]

Mexican temperate forests, at the southernmost end of the distribution range of this ecosystem, are the world's centre of diversity of pine and oak, with 55 and 161 species, respectively. Such forests are threatened by land-use change, unsustainable forest management practices, and climate change; these threats reduce their diversity, alter the distribution ranges of species, modify disturbance regimes, and reduce ecosystem adaptability. This paper briefly reviews (i) the ecology of the Mexican temperate forests, (ii) the ecological basis for the unique diversity of pine and oak species, (iii) the main disturbances as well as the main drivers of global changes affecting these forests, in particular climate change, and (iv) the social, economic, and cultural factors to be considered in proposing a new forest management approach. It proposes a new conceptual framework to manage Mexican temperate forests that are in line with (i) their natural dynamics, (ii) the rapidly changing and uncertain global environmental, social, and economic conditions, and (iii) the complex adaptive system approach. This new forest management combines functional zoning, multispecies plantations, and sylvicultural interventions to increase the adaptive capacity of forests as a way to balance the increasing need for timber products with the need for other ecosystem services facing rapidly changing and uncertain future environmental, social, and economic conditions. Key words: adaptability, biodiversity, climate change, disturbances, fire regime, forest income. Les forets temperees mexicaines, situees a l'extreme sud de l'aire de repartition de cet ecosysteme, sont le centre mondial de la diversite de pins et de chenes comptant 55 et 161 especes, respectivement. Ces forets sont menacees par la facon dont elles sont utilisees, par des pratiques de gestion de forets non durable et du au changement climatique; ces menaces reduisent leur diversite, modifient les aires de repartition des especes, modifient les regimes de perturbations et reduisent l'adaptabilite de l'ecosysteme. Cet article examine brievement (i) l'ecologie des forets temperees mexicaines, (ii) la base ecologique de la diversite unique d'especes de pins et de chenes, (iii) les principales perturbations ainsi que les principaux moteurs des changements globaux qui affectent ces forets, en particulier le changement climatique, et (iv) les facteurs sociaux, economiques et culturels, a prendre en consideration, en proposant une nouvelle approche de la gestion forestiere. Cet article propose un nouveau cadre conceptuel pour gerer les forets temperees mexicaines conforme avec (i) leur dynamique naturelle, (ii) les conditions environnementales, sociales et economiques globales, en changement continuel et incertaines, et (iii) l'approche adaptative du systeme complexe. Cette nouvelle gestion forestiere combine un zonage fonctionnel, des plantations multi-especes et des interventions sylvicoles pour augmenter la capacite d'adaptation des forets afin d'equilibrer la necessite croissante des produits forestiers avec la necessite de d'autres services ecosystemiques exposes a des conditions environnementales, sociales et economiques qui sont en changement continuel et incertaines. Mots-cles: adaptabilite, biodiversite, changement climatique, perturbations, regime de feu, revenu de la foret., Mexican temperate forests Mexican temperate forest ecosystems include single-species or mixed forests of pine (Pinus spp.), oak (Quercus spp.), and many other genera such as Abies, Pseudotsuga, Picea, Cupressus, and [...]

Multilevel governance (MLG) and co-management are indispensable to sustainable forest management (SFM) and the maintenance of ecosystem services (ES). Through interviews with key external and community actors and workshops in two ejidos in central Mexico, we qualitatively analyzed information on the historical and current uses of forests and the ways the ejidos evolved toward SFM by implementing MLG regulatory frameworks that enabled forest co-management. By studying the perceptions of local stakeholders and the relevance of their interactions to effective local forest management, we found that the history of forest use in the region has favored the local appropriation of socioecosystems through co-management. However, these principles have not simply led to harmonized development and conservation. Although such technical interventions favor forest productivity in local communities, the stakeholders also recognize that certain adjustments could improve and maintain the local ES. Thus, while the conditions of community forest management in Mexico exemplify how local decision-making processes can be both relatively democratic and ecologically beneficial for local communities, it is also necessary to move from a traditional management model to shared governance in community contexts. [ABSTRACT FROM AUTHOR]

The significance of Latin America (LA) in the global food supply is large and prominent. The livestock sector at this time faces social-ecological challenges that will be accentuated in the future and will be incredibly challenging for small and medium producers. We conducted a systematic literature review to understand the role of LA cattle ranching in the current sustainability debate. In addition, we identified the main components of cattle ranching social-ecological systems and evaluated the institutional and ecological interactions of livestock studies by identifying spatial and temporal scales. Our results show a broad debate on livestock sustainability in LA; nevertheless, efforts to measure sustainability and analyze cattle ranching systemically are scarce. The study of LA cattle ranching in the 21st century was geographically concentrated on the main producing countries (Mexico, Colombia, Brazil, and Argentina) and was consistently promoted by government and academic institutions aiming to understand management strategies that improve yields. However, it less often focused on analyzing their impacts on ecosystems and climate. The complexity and dynamism of cattle ranching in LA make it necessary to address sustainable planning from a systemic approach to guide viable transformations through spatial scales. [ABSTRACT FROM AUTHOR]

Sustainable silvicultural management requires the maintenance of long-term ecosystem processes. We used the CENTURY model to simulate the impact of wood extraction and organic amendments on aboveground biomass, carbon (C) storage, and the availability of nitrogen (N) in the two dominant silvicultural methods in Mexico: the silvicultural development method (SDM) and irregular forest management (IFM). The values of the mean absolute percentage error for the SDM and IFM were 2.1% and 3.3% for C in aboveground biomass, 5.7% and 5.0% for soil organic carbon (SOC), and 14.9% and 21.6% for N, respectively. Simulation for the SDM (1967–2068) suggested a reduction of ~7% in C in soil, microbial biomass, and litter, 9% in aboveground biomass C, and ~20% in the mineral N available. For IFM, the simulation (2009–2019) suggested a reduction of 14% in the accumulation of aboveground biomass and 13% in the mineral N available. Simulation of the adoption of management practices suggested that N mineral availability would increase by 2%–3% without drastically reducing the SOC, improving aboveground biomass production by ~7%, in each management system. Study Implications In Mexico, current silvicultural management is causing alterations in the biological and chemical processes of the soil, but the future impacts on the production of forest wood and loss of fertility cannot be estimated by direct measurements. We simulated two silvicultural management alternatives with two rotation cycles and measured the response in terms of SOC, nitrogen availability, and aboveground biomass. The model shows that improving forest residue management by adding organic amendments to the soil would counteract changes in soil microbial activity, nitrogen availability, SOC, and aboveground biomass in the future. Managers should consider this information to reorient current crop residue management to achieve the objectives and the sustainability of forest management in Mexican temperate forests. [ABSTRACT FROM AUTHOR]

Copyright of Tropical Grasslands / Forrajes Tropicales is the property of International Centre for Tropical Agriculture - CIAT 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.)

Forest plantations are a possible way of increasing forest productivity in temperate and tropical forests, and therefore also increasing above- and belowground carbon pools. In the context of climate change, monospecific plantations might become an alternative to mitigate global warming; however, their contribution to the structural complexity, complementarity, and biodiversity of forests has not been addressed. Mixed forest plantations can ensure that objectives of climate change mitigation are met through carbon sequestration, while also delivering anticipated ecosystem services (e.g., nutrient cycling, erosion control, and wildlife habitat). However, mixed forest plantations pose considerable operational challenges and research opportunities. For example, it is essential to know how many species or functional traits are necessary to deliver a set of benefits, or what mixture of species and densities are key to maintaining productive plantations and delivering multiple ecosystem services. At the same time, the establishment of forest plantations in Mexico should not be motivated solely by timber production. Forest plantations should also increase carbon sequestration, maintain biodiversity, and provide other ecosystem services. This article analyzes some matters that affect the development of planted forests in the Mexican national context, and presents alternatives for forest resources management through the recommendation of mixed forest plantations as a means of contributing to climate change mitigation and the delivery of ecosystem services. [ABSTRACT FROM AUTHOR]

Copyright of Forestry Chronicle is the property of Canadian Institute of Forestry 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.)

Identification of the ecosystem services provided by Mexican temperate forests is a prerequisite in ensuring their conservation and sustainable management. This study aimed (1) to describe ecosystem services provided by Mexican temperate forests (provisioning, regulating and cultural services); and (2) to identify possible trade-offs and synergies based on the types of ecosystem services available in Mexican temperate forests. We synthesized relevant literature from scientific articles, government statistics and grey literature covering the years 1985–2012. Timber extraction is the main beneficial ecosystem service of temperate forests recognized by public policy as shown by the high income from this activity; but it has trade-offs of greater magnitude with other provisioning services (water, bioenergy and non-timber forest resources), and with other supporting, regulating and cultural ecosystem services. For example, it causes the loss of other forest resources, extinction of commercially important species and loss of the system's structural complexity. Water capture and extraction of non-timber forest resources have lesser effects on support and regulation services, and in the case of water capture, the magnitude of the effect depends on the type and reversibility of the modification of the ecosystem. The synergies between ecosystem services have mutual benefits; for example, a decision to enhance the scenic beauty in temperate forests potentially improves water cycling and provision of non-timber forest resources, and has a positive effect on cultural and regulation services. In Mexican temperate forests the recognition of ecosystem services is limited and is based largely on grey literature. More robust scientific information is needed on the role of these forests in maintaining biodiversity and provision of ecosystem services essential to the welfare of the population. Also, monitoring of ecosystem processes of highland temperate forests in tropical regions is very limited, so it is necessary to generate research to develop a paradigm shift from forest management based strictly on logging to one based on ecosystem management. [ABSTRACT FROM PUBLISHER]

Understanding and analysis of drivers of land-use and -cover change (LUCC) is a requisite to reduce and manage impacts and consequences of LUCC. The aim of the present study is to analyze drivers of LUCC in Southern Mexico and to see how these are used by different conceptual and methodological approaches for generating transition potential maps and how this influences the effectiveness to produce reliable LUCC models. Spatial factors were tested for their relation to main LUCC processes, and their importance as drivers for the periods 1993–2002 and 2002–2007 was evaluated by hierarchical partitioning analysis and logistic regression models. Tested variables included environmental and biophysical variables, location measures of infrastructure and of existing land use, fragmentation, and demographic and social variables. The most important factors show a marked persistence over time: deforestation is mainly driven by the distance of existing land uses; degradation and regeneration by the distance of existing disturbed forests. Nevertheless, the overall number of important factors decreases slightly for the second period. These drivers were used to produce transition potential maps calibrated with the 1993–2002 data by two different approaches: (1) weights of evidence (WoE) to represent the probabilities of dominant change processes, namely deforestation, forest degradation, and forest regeneration for temperate and tropical forests and (2) logistic RM that show the suitability regarding the different land-use and -cover (LUC) classes. Validation of the transition potential maps with the 2002–2007 data indicates a low precision with large differences between LUCC processes and methods. Areas of change evaluated by difference in potential showed that WoE produce transition potential maps that are more accurate for predicting LUCC than those produced with RM. Relative operating characteristic (ROC) statistics show that transition potential models based on RM do usually better predict areas of no change, but the difference is rather small. The poor performance of maps based on RM could be attributed to their too general representation of suitability for certain LUC classes when the goal is modeling complex LUCC and the LUC classes participate in several transitions. The application of a multimodel approach enables to better understand the relations of drivers to LUCC and the evaluation of model calibration based on spatial explanatory factors. This improved understanding of the capacity of LUCC models to produce accurate predictions is important for making better informed policy assessments and management recommendations to reduce deforestation. [ABSTRACT FROM PUBLISHER]

In degraded soils of tropical seasonal pastures, native remnant tree species that differ in foliar morphology, litter quality, and quantity might be quite useful as an organic input for improving soil fertility. The objective of this study was to analyze litter quality effects on soil microbial activity from two native remnant trees: Caesalpinia eriostachys Benth. (Caesalnaceae) and Cordia elaeagnoides DC (Boraginaceae), located within a tropical seasonal pasture matrix dominated by Panicum maximum Jacq. (Poaceae). The substrate-induced respiration method was used to determine soil microbial activity in a laboratory incubation experiment. A 3 × 3 factorial laboratory experiment for litter type and soil origin was carried out by adding leaf litter to soil in a reciprocal fashion to evaluate the relative effect of litter quality on substrate-induced respiration. Potential C mineralization rate and net microbial C immobilization from soil under C. elaeagnoides and C. eriostachys were higher with endogenous litter (260 ± 24 µg C g-1 d-1 and 242 ± 11 µg C g-1 d-1 for C. elaeagnoides and C. eriostachys, respectively) than with exogenous litter. Potential carbon mineralization and net microbial C immobilization in soil under P. maximum increased with litter from C. eriostachys due to other leaf-litter quality parameters as lignin concentration and lignin:N ratio. Therefore, C. eriostachys litter addition on soil under grass species may help to stabilize soil organic matter, promoting soil microbial biomass and activity. The net immobilization of microbial N under two remnant tree species and grass species was negative, indicating an N mineralization from microbial biomass. [ABSTRACT FROM AUTHOR]

Temperate forests play a significant role in the global carbon cycle. However, deforestation, land use changes and differences in successional and species composition cause a spatial heterogeneity in the potential carbon storage in the landscape. The aims of this study were (1) to quantify aboveground and belowground biomass and respective carbon storage and (2) to project the future carbon storage in temperate forests landscape in Cofre de Perote, Veracruz, Mexico. Aboveground and belowground biomass was estimated in seven forests with different species composition and conservation status and management, in three grasslands and in two shrublands at a range of altitudes. Total biomass in forests ranged from 91.07 to 383.78 Mg ha−1, in grassland from 9.83 to 24.93 Mg ha−1 and in successional (shrublands) from 6.33 to 7.69 Mg ha−1. This suggests that deforestation and changes of land use could reduce aboveground biomass by 90 per cent. Mature forests had the largest aboveground and belowground biomass and the lowest density (number of trees per hectare) but a lower potential for accumulation of C in the future; in contrast, young forests and reforested areas had higher growth and carbon storage potential. Our results suggest that avoiding deforestation and improving forest management could play a major role in global climate change mitigation. [ABSTRACT FROM AUTHOR]

In spite of widely documented studies of deforestation rates and land use/cover changes in tropical dry forests in Mexico, relatively little is known about fragmentation patterns in such forests. This study defines the spatial distribution of landforms and land use/cover types the lower Papagayo River basin and examines their influence on fragmentation patterns and biological diversity in a tropical dry forest in that southern Pacific region. The land use/cover map was constructed from aerial photographs, Landsat TM imagery (2000) and fieldwork. Landform units were defined based on altitude, slope, lithology and morphology. Landscape fragmentation parameters were obtained using FRAGSTATS (version 3.3) considering the numbers of patches, mean, minimum and maximum patch size, edge density, total edge and connectivity. Results show tropical dry forest to be remnant vegetation (~11 per cent), characterized by isolation and low connectivity. Land use/cover types have different effects on fragmentation patterns. Agriculture and cattle raising produce similar numbers of patches, but with a different mean size; and human settlements have a scattered distribution pattern. The abandonment of rural agricultural livelihoods has favoured the expansion of secondary tropical dry forest characterized by continuity and high connectivity, which suggests a high regeneration potential from land abandonment. It can be concluded that tropical dry forest fragmentation and recovery at regional scales depend on such landscape attributes as lithology, slope, geomorphology and management. [ABSTRACT FROM AUTHOR]

Models can help to explain the main interactions, magnitudes, and velocity by which biological processes accumulate soil organic carbon (SOC) in pastures. An explanatory model using Insight Maker software was constructed for each soil under natural and cultivated pastures, using theoretical carbon models and data which were collected monthly in andisol sites. The model was calibrated and validated by comparing the modeled data to the field data until the smallest prediction error was reached. The indicators used were the mean absolute error (MAE), root-mean-square error (RMSE), mean absolute percentage error (MAPE) and the coefficient of determination (R2). In natural pasture soil, the diversification of organic inputs consistently promoted the growth of microbial biomass and metabolic efficiency. In contrast, intensive management of cultivated pastures, involving the removal of plant cover, plowing and low input of organic matter, stressed the microbial community and increased the potential carbon loss through secondary mineralization and surface runoff. The application of modeling indicated that it is necessary to improve agronomic practices in cultivated pastures, to maintain soil cover and to increase the application of organic fertilizer by 1.5 times, in order to reduce stress on the microbial biomass, accumulate SOC, minimize organic matter mineralization and reduce C losses due to surface runoff. Therefore, improving agricultural management based on the understanding of soil processes will allow increasing the potential for SOC storage, while improving pasture sustainability. [ABSTRACT FROM AUTHOR]