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Abstract Background The Calakmul Biosphere Reserve (CBR) is known for its rich animal and plant biodiversity, yet its microbial communities remain largely unknown. The reserve does not possess permanent bodies of water; nevertheless, seasonal depressions associated with fractures create wetlands, known locally as aguadas. Given the recent construction of the Maya train that crosses the CRB, it is essential to assess the biodiversity of its microorganisms and recognize their potential as a valuable source of goods. This evaluation is pivotal in mitigating potential mismanagement of the forest ecosystem. To enhance comprehension of microbial communities, we characterized the microbiota in three different wetlands. Ag-UD1 and Ag-UD2 wetlands are located in a zone without human disturbances, while the third, Ag-SU3, is in a semi-urbanized zone. Sampling was carried out over three years (2017, 2018, and 2019), enabling the monitoring of spatiotemporal variations in bacterial community diversity. The characterization of microbiome composition was conducted using 16S rRNA metabarcoding. Concurrently, the genomic potential of select samples was examined through shotgun metagenomics. Results Statistical analysis of alpha and beta diversity indices showed significant differences among the bacterial communities found in undisturbed sites Ag-UD1 and Ag-UD2 compared to Ag-SU3. However, no significant differences were observed among sites belonging to the undisturbed area. Furthermore, a comparative analysis at the zone level reveals substantial divergence among the communities, indicating that the geographic location of the samples significantly influences these patterns. The bacterial communities in the CBR wetlands predominantly consist of genera from phyla Actinobacteria, Acidobacteria, and Proteobacteria. Conclusion This characterization has identified the composition of microbial communities and provided the initial overview of the metabolic capacities of the microbiomes inhabiting the aguadas across diverse conservation zones. The three sites exhibit distinct microbial compositions, suggesting that variables such as chemical composition, natural and anthropogenic disturbances, vegetation, and fauna may play a pivotal role in determining the microbial structure of the aguadas. This study establishes a foundational baseline for evaluating the impact of climatic factors and human interventions on critical environments such as wetlands.

Background: The Calakmul Biosphere Reserve (CBR) is known for its rich animal and plant biodiversity, yet its microbial communities remain largely unknown. The reserve does not possess permanent bodies of water; nevertheless, seasonal depressions associated with fractures create wetlands, known locally as aguadas. Given the recent construction of the Maya train that crosses the CRB, it is essential to assess the biodiversity of its microorganisms and recognize their potential as a valuable source of goods. This evaluation is pivotal in mitigating potential mismanagement of the forest ecosystem. To enhance comprehension of microbial communities, we characterized the microbiota in three different wetlands. Ag-UD1 and Ag-UD2 wetlands are located in a zone without human disturbances, while the third, Ag-SU3, is in a semi-urbanized zone. Sampling was carried out over three years (2017, 2018, and 2019), enabling the monitoring of spatiotemporal variations in bacterial community diversity. The characterization of microbiome composition was conducted using 16S rRNA metabarcoding. Concurrently, the genomic potential of select samples was examined through shotgun metagenomics. Results: Statistical analysis of alpha and beta diversity indices showed significant differences among the bacterial communities found in undisturbed sites Ag-UD1 and Ag-UD2 compared to Ag-SU3. However, no significant differences were observed among sites belonging to the undisturbed area. Furthermore, a comparative analysis at the zone level reveals substantial divergence among the communities, indicating that the geographic location of the samples significantly influences these patterns. The bacterial communities in the CBR wetlands predominantly consist of genera from phyla Actinobacteria, Acidobacteria, and Proteobacteria. Conclusion: This characterization has identified the composition of microbial communities and provided the initial overview of the metabolic capacities of the microbiomes inhabiting the aguadas across diverse conservation zones. The three sites exhibit distinct microbial compositions, suggesting that variables such as chemical composition, natural and anthropogenic disturbances, vegetation, and fauna may play a pivotal role in determining the microbial structure of the aguadas. This study establishes a foundational baseline for evaluating the impact of climatic factors and human interventions on critical environments such as wetlands. [ABSTRACT FROM AUTHOR]

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The interplay among conservation, agricultural policy, and rainfall variability can intensify hardship for those practicing smallholder agriculture, especially in tropical developing countries. This article addresses these challenges as faced by the municipality of Calakmul, Mexico. Forty in-depth, semi-structured interviews with smallholders, governmental agents, and NGO representatives, all conducted between July and November 2018, are paired with quantitative precipitation analyses. Interviews cited changes in the production system and in smallholders' livelihoods, including the intensification of production across a smaller area coupled with shorter fallow periods and a greater reliance on agricultural subsidies and inputs, which are driven both by agricultural policies and conservation policies to decrease deforestation rates. Precipitation analyses demonstrated that, even though annual and seasonal rainfall trends in Calakmul are slightly positive during the study period, the onset of the rainy season and the intensity of rains have been changing. Results indicate an increased intensity of rainfall events, with delayed onset of precipitation and considerable interannual variability. Though conservation in the area is a widely cited priority, results showed that agricultural policies and precipitation changes are dominant influences on smallholders' agricultural decisions. Therefore, any [End Page 112] successful conservation measures should be aligned to agricultural and climate change policies. [ABSTRACT FROM AUTHOR]

Water quality degradation by organochlorine pesticides and potentially toxic elements is of worldwide concern. This research explores groundwater conditions, regarding organochlorine pesticides and potentially toxic elements, in Hopelchen, Campeche, which is located in the buffer zone of the Calakmul Biosphere Reserve. Unfortunately, agriculture is allowed and agrochemical use is not monitored and sanctioned. Results show that Heptachlor, Endosulfan, and Dieldrin, all recognized carcinogens, had concentrations above the Mexican normative recommended values. Conversely, Cd and Ni concentrations were below recommended values. These results demonstrate that government intervention involving immediate control over agrochemical use is mandatory. Also, the results underscore the contamination of groundwater in several of the Calakmul Biosphere Reserve's buffer zones by organochlorine pesticides concentrations, posing a probable threat for local inhabitants who consume this water and use it for recreation. [ABSTRACT FROM AUTHOR]

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Highlights • Deforestation creates a hot environment, thus water is not capable to balance temperature differences in both time and space modifying the local and regional scale hydrological cycle and influencing the climate not only at these scales but to the Earth climate. • Most of the surface corresponds to high permeability type forming a karstic relief, where water is stored in Aguadas used only by nearby communities. • The studied sites at the RBC could be divided into three areas according to several factors some of them soil type, vegetation and climate: North, South, and Archaeological. • The natural influence by rock washing or erosion in the subsurface and surface has a direct effect on the ecosystem due to the presence of carbonates, sodium, calcium, magnesium and potassium. Although DO concentration (% of saturation) suggests that primary production continues being an emergent macrophyte dominated system. • As and V were only detected in La Ceiba aguada, a cenote isolate from the inhabitants. • Although, cadmium, manganese, cupper, iron, aluminium, barium and strontium were detected in all the aguadas and presented values above the permitted limits by the NMX-AA-131-SCFI-2005, they are in agreement with the criteria for protection of aquatic life. Abstract Hydrological aspects in ecosystems are defined as those that support the availability of water. This involves the analysis of ecosystems establishing their ecological interactions as well as external factors such as humans’ presence, changes in seasonal patterns of flow, physicochemical characteristics of water bodies, and the type and amount of pollutants entering these water bodies mostly due to surface but also some subsurface runoff. The aim of this article is to establish if soil type, vegetation or land use changes have a major impact affecting water quality in aguadas (a type of cenotes) and therefore its availability as a source of water in a rain forest ecosystem with karst soil and shortages. For this, nine aguadas were monitored in a Natural Protected area, whose importance is based on sustaining the ecosystem of different species, as well as to provide a source of water supply. The monitoring work considered soil and vegetation characteristics and water quality, in the aguadas, with and without direct human impact. Results showed that the studied sites at the Calakmul Biosphere Reserve (RBC) can be divided into three areas according to several factors some of them soil type, vegetation and climate. For each of the studies sites, sample tests of microorganisms, physico-chemical parameters and metals were performed. It was observed that deforestation around water bodies, transforming jungle into agricultural land, is critical since it creates a climatic transition zone affecting the water balance, and generates erosion moving nutrients and soil materials into water bodies. Additionally, the presence of total coliforms due to the combined use of water for human and animal use was observed. The natural influence by rock washing or erosion in the subsurface and surface has an effect on production systems due to the presence of carbonates, sodium, calcium, magnesium and potassium. Besides these elements, all aguadas also have high concentrations of: cadmium, manganese, cupper, iron, aluminium, barium and strontium but they are agreed with the Water Quality Criteria. La Ceiba aguada has some traces of arsenic 0.019 mg/L and vanadium 0.041 mg/L. The presence of these elements need to be specified (natural or anthropogenic causes) in order to propose a treatment process. Based on this, soil and vegetation are clue to define water quality in a natural reserve, thus it is necessary to reduce deforestation and recovering the capacity of the resilience through a sustainable forest management. [ABSTRACT FROM AUTHOR]

The southern Yucatán (SY) has been recognized as a hotspot of biodiversity with great risk of deforestation. Land change analysis, based on classified Landsat TM and ETM + satellite imagery (1990, 2000 and 2006), was used to estimate the annual deforestation rates of 141 land management units of the SY, and spatial patterns of forest fragmentation around and within the Calakmul Biosphere Reserve (CBR), which comprises approximately one-third of the region. Results indicate a decrease in annual deforestation rates over 1990–2006, from 0.15% year−1to 0.06% year−1, but with significant sub-regional variations in the quantity and rate of forest loss. Despite a decline in deforestation during this period, there was considerable fragmentation both inside and outside the CBR. While population pressures and the expansion of pasture have caused deforestation across the region, agricultural intensification, diversified income strategies and reserve conservation may have contributed to reduced forest loss during the study period. [ABSTRACT FROM AUTHOR]

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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]

Abstract: Consistent with the challenges of sustainability science, land architecture offers a comprehensive approach to land system dynamics useful for numerous types of assessments, ranging from the vulnerability of coupled human–environment systems to forest transitions. With antecedents in several research communities, land architecture addresses the tradeoffs within and between the human and environmental subsystems of land systems in terms of the kind, magnitude, and pattern of land uses and covers. This approach is especially cogent for changes in tropical forests, given the broad-ranging forces acting on them and the equally broad-ranging consequences of their loss. The rudiments of the land architecture approach are illustrated for changes in seasonal tropical forests in the southern Yucatán of Mexico, the pivot of which is the Calakmul biosphere reserve. Simplifying the dynamics involved, the region-wide land architecture is the collective design of stakeholders with different land-use goals that favor tradeoffs in subsystem outcomes serving better either the reserve and related programs or the smallholder farmers that populate the region. A major tradeoff involves forest cover per se, which holds implications for forest transition theory. Evidence for an incipient transition involves the scale of analysis taken. The dynamics involved hold too much uncertainty to forecast a permanent transition to more forest cover and imply that more complex but robust versions of the theory are required. [Copyright &y& Elsevier]

The white-lipped peccary (Tayassu pecari) is a neotropical ungulate that forms some of the largest groups living in dense tropical forest. Populations of this species have declined throughout Mesoamerica during the last 50 years at alarming rates. Home-range and habitat preferences of this species have been documented in Brazil and Costa Rica for humid tropical forest. Here we studied home-range features and habitat preferences of white-lipped peccaries for a seasonally dry tropical forest of the Yucatan Peninsula--the Calakmul Biosphere Reserve--where water and food can be temporarily scarce or even absent. By using radiotelemetry and direct observations for 18 months of individuals in 4 groups, we documented some of the largest home ranges reported for some of the smallest group sizes documented for this species. Dry-season home ranges were constrained to the close vicinity of a few available water sources, whereas during the rainy season peccary groups were more mobile and traversed long distances. Compositional analyses of habitat preferences indicated that groups preferred ponds and Medium Sub-Perennial Forest in combination with Low Flooded Forest, whereas the least preferred was the Dry Forest. Apparently, the combination of ranging over large areas to access widely dispersed resources while living in smaller groups and sharing space allows white-lipped peccaries to survive in Calakmul. [ABSTRACT FROM AUTHOR]

Abstract: The federal policy of Natural Protected Areas has become the main instrument for conserving biodiversity in Mexico. Established in territories representative of different ecosystems but also of cultural diversity, protected areas in Mexico have historically been created and managed with a centralized rationale, creating several conflicts with local communities over the use of natural resources. The country''s approach to protected areas perfectly illustrates the complexities, difficulties and challenges entailed in biodiversity conservation. This paper develops a critical analysis of this policy instrument in Mexico, and analyzes three Natural Protected Areas in the Yucatan Peninsula: The Calakmul Biosphere Reserve, the Celestún Biosphere Reserve, and the Otoch Ma’ax Yetel Kooh Natural Protected Area. The case studies serve as examples of the most common difficulties that arise in Mexican Natural Protected Area policy: (1) uncoordinated public policies; (2) the usual conflict between environmental authorities and local people over the management of natural resources; and (3) the exclusion of local people''s perspectives, values and beliefs in conservation policy development and implementation. [Copyright &y& Elsevier]

Copyright of Tropical Conservation Science is the property of Sage Publications Inc. 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.)

The phenology of butterflies was analyzed in the Calakmul Region (CR) in the state of Campeche, México, over the course of 3 years. Altogether, 60,662 individuals were recorded, consisting of 359 species in 207 genera, 18 subfamilies, 5 families, and 2 superfamilies. Greatest species diversity was recorded during Oct and Nov. Monthly fluctuation in diversity was defined by rare species. Hesperiidae (135 species) and Nymphalidae (111 species) were the most diverse families, and showed the greatest variation with respect to distribution of species richness throughout the year. Papilionidae showed the greatest species richness during the dry season. Pieridae, Nymphalidae, and Lycaenidae showed peaks of greatest species richness and relative abundance during the rainy season. Results were compared to faunal studies of the Sierra de Atoyac de Álvarez, in the state of Guerrero, and of the Sierra de Manantlán, in Jalisco and Colima. Important similarities were observed among phenological patterns in the butterfly fauna of the 3 regions, especially between CR and Manantlán. The phenology of species with greater relative abundance was analyzed in relation to wingspan as a parameter of adult size. The small and medium-sized groups, taken together, showed variations in species richness. An analysis of species seasonality was conducted with NMDS, ANOSIM and SIMPER, in the program PRIMER 4.0. Differences among the composition of butterfly communities with respect to the seasons were found. [ABSTRACT FROM AUTHOR]

Abstract: Current status and trends of deforestation are assessed for the region of La Montaña, Campeche, Mexico, a buffer zone for the Calakmul Biosphere Reserve, by interpreting remotely sensed satellite image data. A change detection analysis of three satellite images was used to assess forest clearing for agriculture from two time periods (1988–2000 and 2000–2005). Buffers from specific variables (distance to roads, distance to settlements and proximity to lowland flooded forest) were used to assess deforestation patterns and identify potential variables that determine land use change. Results show annual deforestation rates increase from 0.3% between 1988 and 2000 to 0.7% between 2000 and 2005, which indicate that forest conversion is intensifying. Deforestation appears to be prominent near lowland flooded forests on soil types identified by local people as suitable for agriculture, particularly for pasture establishment. Recent occurrence of deforestation in the area is strongly associated with soil/vegetation characteristics, infrastructure development and settlement locations while the proximate causes are related to agricultural expansion. Although the economy in the region is still greatly dependent on traditional forest management, in the last decade cattle ranching has been institutionally promoted and is an economic alternative that has been increasing in importance. [Copyright &y& Elsevier]

The article presents the land changes in the southern Yukatan and Calakmul Biosphere Reserve and their implications on the protection capacity of the reserve. Protected biodiversity include the ecoline, forest habitats and butterfly diversity of the places. Increasing settlement and the expansion and intensification of agriculture have led to the loss of the amount and proximity of older forest patches beyond the reserve and the loss of humid forests and the interruption of biota flow across the ecoline. An adaptive management approach is highly recommended for the case.

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Copyright of Landscape & Urban Planning is the property of Elsevier B.V. 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.)