Central Highlands Of Chiapas Research Articles

<p class="MsoTitle"><span lang="EN-GB">Magnolia montebelloensis</span><span lang="EN-GB">, a new species in section Magnolia from Lagunas de Montebello National Park, Chiapas, México, with a key to Magnoliaceae of Chiapas</span>

A new species of Magnolia, from the Lagunas de Montebello National Park, in the central highlands of Chiapas, Mexico, is described and illustrated. Magnolia montebelloensis belongs to section Magnolia; it differs from M. poasana in its smaller habit, densely pubescent terminal twig internodes, stipules and spathaceous bracts, shorter peduncular internodes and more numerous stamens. A key, an ecological and a conservation assessment of the eight Chiapan species of Magnoliaceae are included. Magnolia montebelloensis grows in montane rain forest and is contrasted with other Chiapan Magnolia species regarding their climate and vegetation preferences. It was assessed as critically endangered (CR) according to IUCN B1ab(ii, iii) and B2ab(iii) criteria. Half of Magnolia species in Chiapas occur in protected natural areas, and thus immediate action is required to protect the other four species, M. faustinomirandae, M. mayae, M. sharpii and M. zamudioi. Seven out of the eight Magnolia species (88%) are not found in ex-situ collections despite being endangered or critically endangered.

Stelis zootrophionoides (Orchidaceae: Pleurothallidinae), a New Species from Mexico

Background Stelis (Orchidaceae) encompasses approximately 1100 species of epiphytic orchids distributed throughout the Neotropics, with the highest diversity in Andean South America. Sixty-two species were recorded previously in Mexico.MethodsWe formally describe here Stelis zootrophionoides as a new species from Chiapas, Mexico. To determine its systematic position, we conducted a morphological comparison with other members of Pleurothallidinae and a phylogenetic analysis of nucleotide sequences from the plastid matK/trnK and trnL/trnF regions, as well as the nuclear ribosomal ITS region for 52 species of Pleurothallidinae. Sequences of 49 species were downloaded from GenBank and those of three species, including the new taxon, were newly generated for this work. The new species is described and illustrated; notes on its ecological preferences and a comparison with closely related species are presented.ConclusionsThe new species, known only from one location and apparently restricted to the cloud forest in the central highlands of Chiapas, Mexico, is considered a rare species. This small epiphyte is unique among the Mexican species of Stelis by the combination of dark purple flowers with the distal third of the dorsal sepal adhered to the apices of the lateral sepals, which are partially united into a bifid synsepal, leaving two lateral window-like openings, and sagittate labellum. Stelis jalapensis, known from southern Mexico and Guatemala, also has the apices of the sepals adhered to each other, but it is distinguished by its larger flowers with lanceolate, acute dorsal sepal, completely fused lateral sepals (i.e. the synsepal is not bifid), and oblong-elliptic labellum. The phylogenetic analysis shows that S. zootrophionoides is closely related to other Mexican Stelis and corroborates previous suggestions that fused sepal apices have arisen independently in different lineages of Pleurothallidinae.

Natural History of the Threatened Bearded Screech-Owl (Megascops Barbarus) in Chiapas, Mexico

We describe morphological measurements, breeding biology, roost-site characteristics, and diet of the endemic and threatened Bearded Screech-Owl (Megascops barbarus) in the central highlands of Chiapas, Mexico. The first nest recorded for this species was in a natural cavity of an old oak (Quercus laurina) and contained a single nestling. Four roosting sites were located, two in Clethra chiapensis (evergreen broadleaf) and two in Pinus ayacahuite (pine; mean height = 3.4 m). Fecal analysis indicated that diet was primarily insectivorous, consisting of Melononthidae (Coleoptera; 72.3%), along with a few Orthoptera (9.2%), Lepidoptera (3.1%), and Arachnida (1.5%). Data from 39 owls (24 captured and 15 skins) were used for morphology analysis. This species exhibited reversed sexual dimorphism, with females having greater mass and longer tails than males. Molting occurred during the rainy season (July to October), with the primary and secondary feathers being molted simultaneously. Subcutaneous fat was moderate to abundant in the dry season only (December to May). Maximum longevity we recorded was at least 4.17 yr. These first natural history data for the species provides preliminary information for understanding the ecological requirements of the Bearded Screech-Owl in fragmented tropical montane forest.

INFLUENCE OF HABITAT VARIATION, NEST-SITE SELECTION, AND PARENTAL BEHAVIOR ON BREEDING SUCCESS OF RUDDY-CAPPED NIGHTINGALE THRUSHES (CATHARUS FRANTZII) IN CHIAPAS, MEXICO

We examined the influence of ecological and behavioral factors on breeding success of Ruddy-capped Nightingale Thrushes (Catharus frantzii) in contiguous primary- and secondary-forest habitats during the 2000–2003 breeding seasons in the Central Highlands of Chiapas, Mexico. Breeding density was higher in primary, undisturbed forest than in secondary forest with less understory vegetation. Nest-site selection was related to nest-concealment attributes (visibility, canopy cover, and shrub density) at the nest-site and patch levels. Nest-site selection was stronger in secondary forest, which indicates that preferred nest-site attributes were more limited in that habitat. Overall success per breeding attempt varied annually from 20% to 35%, with a higher mean annual success in primary forest (42%) than in secondary forest (19%). Daily nest survival rates were higher in primary than in secondary forest and varied with nest cover, lateral visibility, and density of ground epiphytes. The number of parental visits to nests was higher in primary than in secondary forest and lower for successful than for failed nests during incubation but did not vary with habitat or fate during the nestling stage. Female nest-attentiveness was higher in primary forest than in secondary forest throughout the nesting attempt and was higher for successful nests during the nestling stage only. Thus, Ruddy-capped Nightingale Thrushes showed habitat-specific breeding performance, with the primary-forest habitats (cloud forest, riparian) supporting higher densities and nesting success than secondary, disturbed habitats.

The Extent, Distribution, and Fragmentation of Vanishing Montane Cloud Forest in the Highlands of Chiapas, Mexico1

ABSTRACTMontane cloud forest (MCF) has high levels of species diversity, contributes positively to the catchment water yield, and is a globally threatened habitat type. The shortage of reliable data regarding the area currently occupied by MCF remains an obstacle to operational conservation planning in Mexico. This paper assesses how much MCF remains in the central Highlands of Chiapas (Mexico) and how fragmented it is in relation to other forest cover. We estimated that the area covered by MCF was between 3700–5250 ha. This estimate contrasted with the approximately 40,000 ha reported for the same region by the Mexican National Forestry inventory in 2000. MCF was highly scattered and fragmented within a matrix of other tropical montane forest types. Other forest types may be partially buffering the remaining MCF habitats, however, mitigating their disturbance and enhancing their connectivity. We conclude that mechanisms should be sought to promote the protection of core areas containing MCF fragments in agreement with communal and private landowners and to conserve the ecological functions of surrounding buffer zones. Such a conservation strategy would match the natural configuration of these endangered habitats.

Sapling survival and growth of coniferous and broad‐leaved trees in successional highland habitats in Mexico

Abstract. We assessed survival and growth of transplanted saplings of understory broad‐leaved trees (Oreopanax xalapensis, Rapaneajuergensenii, Rhamnus sharpii and Tern‐stroemia lineata) and canopy conifers (Abies guatemalensis, Pinus ayacahuite and P. pseudostrobus) into Grassland (GR), Mid‐Successional Oak Forest (MS), and Old‐Growth Oak Forest (OF) stands in the central highlands of Chiapas, Mexico. A total of 727 plants were monitored over eight years. The results suggest habitat preferences of the studied species that should be considered for their conservation oriented management. Conifers had highest survival and growth in GR, while broad‐leaved trees survived better under sparse canopy in MS, but grew tallest in full light. Saplings of all species in dense canopy sites in OF were smaller, and the survival of conifers was lower. An integrated response index (IRI) calculated for each species with survival and relative growth rates showed similar trends. Re‐introduction of the endangered A. guatemalensis is possible in open habitats if fire, trampling and grazing are suppressed. Open habitats in current man‐made landscapes in the highlands of Chiapas may limit the establishment of understory trees requiring partial shade. Inclusion of such species in restoration programs has not been usual so far; yet, local and global interest in native species for such programs is increasing. Information on the response of these kind of species in contrasting habitats may help to incorporate them in the management of high‐diversity forests that may follow pine plantations.

Sapling survival and growth of coniferous and broad-leaved trees in successional highland habitats in Mexico

We assessed survival and growth of transplanted saplings of understory broad-leaved trees (Oreopanax xalapensis, Rapanea juergensenii, Rhamnus sharpii and Tern- stroemia lineata) and canopy conifers (Abies guatemalensis, Pinus ayacahuite and P. pseudostrobus) into Grassland (GR), Mid-Successional Oak Forest (MS), and Old-Growth Oak Forest (OF) stands in the central highlands of Chiapas, Mexico. A total of 727 plants were monitored over eight years. The results suggest habitat preferences of the studied species that should be considered for their conservation oriented manage- ment. Conifers had highest survival and growth in GR, while broad-leaved trees survived better under sparse canopy in MS, but grew tallest in full light. Saplings of all species in dense canopy sites in OF were smaller, and the survival of conifers was lower. An integrated response index (IRI) calculated for each species with survival and relative growth rates showed similar trends. Re-introduction of the endangered A. guatemalensis is possible in open habitats if fire, trampling and grazing are suppressed. Open habitats in current man- made landscapes in the highlands of Chiapas may limit the establishment of understory trees requiring partial shade. In- clusion of such species in restoration programs has not been usual so far; yet, local and global interest in native species for such programs is increasing. Information on the response of these kind of species in contrasting habitats may help to incorporate them in the management of high-diversity forests that may follow pine plantations.

Germination and survival of tree species in disturbed forests of the highlands of Chiapas, Mexico

Germination and seedling survival of native tree species were studied in nursery (June-November 1998) and forest stands with varying dominance by pines in the central highlands of Chiapas (Mexico; June 1998 - November 1999). Species used are regarded as typical of mid- and late-successional habitats: Cornus disciflora Sessé & Mociño ex DC., Cornus excelsa H.B.K., Drimys granadensis L.f. var. mexicana (DC.) A.C. Smith, Liquidambar styraciflua L., Persea americana L., Quercus laurina H. & B., and Ternstroemia lineata (DC.) ssp. chalicophyla (Loesener) Bartholomew. Nursery treatments included presence and composition of litter collected from replicated plots of three forest types: old-growth forest, mixed pine-oak forest, and pine-dominated forest. Germination and seedling emergence of P. americana in the nursery were complete for all factor combinations. Cornus disciflora and L. styraciflua showed highest germination (p < 0.05) when sown in soil from old-growth forest and covered with litter of oak-broad-leaved species. In the field, differences (p < 0.05) among forest types (degree of pine dominance) were observed for C. disciflora (lowest germination in pinelands, 17%), D. granadensis (highest survival in old-growth forest, 23%), and Q. laurina (higher survival in pinelands, 54%). Natural recruitment and survival of seedlings were higher in old-growth forests. We conclude that oak litter may favor germination and early establishment of the studied species. However, the reintroduction of some of the studied species (C. excelsa, Q. laurina, and T. lineata) may be attempted with direct sowing on the forest floor of severely disturbed and species-poor pinelands.Key words: Cornus, Liquidambar, litter, Persea, Pinus, Quercus, seedling establishment, seeds.

Germination and survival of tree species in disturbed forests of the highlands of Chiapas, Mexico

Germination and seedling survival of native tree species were studied in nursery (June-November 1998) and forest stands with varying dominance by pines in the central highlands of Chiapas (Mexico; June 1998 - November 1999). Species used are regarded as typical of mid- and late-successional habitats: Cornus disciflora Sesse & Mocino ex DC., Cornus excelsa H.B.K., Drimys granadensis L.f. var. mexicana (DC.) A.C. Smith, Liquidambar styraciflua L., Persea americana L., Quercus laurina H. & B., and Ternstroemia lineata (DC.) ssp. chalicophyla (Loesener) Bartholomew. Nursery treatments included presence and composition of litter collected from replicated plots of three forest types: old-growth forest, mixed pine-oak forest, and pine-dominated forest. Germination and seedling emergence of P. americana in the nursery were complete for all factor combinations. Cornus disciflora and L. styraciflua showed highest germination (p < 0.05) when sown in soil from old-growth forest and covered with litter of oak-broad-le...

Land use and deforestation in the highlands of Chiapas, Mexico

Deforestation rates and land-use changes related to environmental factors (slope angle and soil type), in addition to some local population and economic attributes, were estimated from Landsat MSS satellite images of two municipalities of different sizes and for a greater portion of the highlands of Chiapas, Mexico. Annual deforestation rates for 1974–84 and 1984–90 were 1.58 and 2.13%, respectively, in the central highlands of Chiapas; 1.84 and 1.10% in the highly populated Huistán; and 0.46 and 3.42% in the relatively unpopulated Chanal. Changes in the proportion of habitat types differed between the two municipalities between 1974 and 1990 ( p<0.001). Dense forests decreased irrespective of slope angle, while increases were observed in open forested habitats and developed areas. Soil properties also determined the locale and rate of deforestation. In addition to permanent deforestation, a highly dynamic pattern of land-use change was found, and a gradient of degradation of forest structure and floristic composition. These processes appeared to be related to land-use history, as well as to environmental and socioeconomic attributes in each municipality. The current situation in the study region suggests the maintenance and even increasing impact of these processes, complicating the development of solutions to the generalized trend of impoverishment and resource depletion. The results encourage caution in the interpretation, use and analysis of data on the causes and consequences of deforestation, which frequently may not take into consideration the many aspects and scales of this process within a given region.

Land-Use Change and Carbon Flux Between 1970s and 1990s in Central Highlands of Chiapas, Mexico.

/ We present results of a study in an intensively impacted and highly fragmented landscape in which we apply field-measured carbon (C) density values to land-use/land-cover (LU/LC) statistics to estimate the flux of C between terrestrial ecosystems and the atmosphere from the 1970s and 1990s. Carbon densities were assigned to common LU/LC classes on vegetation maps produced by Mexican governmental organizations and, by differencing areas and C pools, net C flux was calculated from the central highlands of Chiapas, Mexico, during a 16-year period. The total area of closed forests was reduced by half while degraded and fragmented forests expanded 56% and cultivated land and pasture areas increased by 8% and 30%, respectively. Total mean C densities ranged from a high of 504 tons C/ha in the oak and evergreen cloud forests class to a low of 147 tons C/ha in the pasture class. The differences in total C densities among the various LU/LC classes were due to changes in biomass while soil organic matter C remained similar. We estimate that a total of 19.99 thick similar 10(6) tons C were released to the atmosphere during the period of time covered by our study, equal to approximately 34% of the 1975 vegetation C pool. The Chiapas highlands, while comprising just 0.3% of Mexico's surface area, contributed 3% of the net national C emissions. KEY WORDS: Land use; Land cover; Carbon flux; Forests; Chiapas highlands; Mexico

An Explanatory Model for the Maya Ethnomedical Syndrome Cha'lam tsots

Although the ethnomedical system of the Highland Maya is generally well understood, little is known about the Tzeltal Maya ethnomedical syndrome Cha'lam tsots, or "second hair." In an attempt to better understand the emic conceptualization, and possible biomedical equivalence of Cha'lam tsots, ethnographic data from semi-structured interviews was collected from the Tzeltal Maya municipality of Tenejapa, in the central highlands of Chiapas, Mexico. Analysis of explanatory models elicited from 20 informants revealed a generalized agreement as to the etiology, symptomatology, course, prognosis, and treatments of this illness. Analysis of these findings will help guide further research into the etiology and biomedical correlate of Cha'lam tsots. This paper concludes with a discussion of the potential significance of this approach for an ethnoepidemiological study of ethnomedical systems, and for the improvement of basic health care services.

The History of Ecological Marginalization in Chiapas

In the hushed morning after San Cristobal's New Year's celebration in 1994, hundreds of masked troops moved through the empty streets, cutting phone lines, dismantling the local security apparatus, and establishing an alternative political order. The revolutionary Zapatista government lasted only four days in San Cristobal and other urban centers of the Central Highlands of Chiapas, Mexico. In the following year, the Ejercito Zapatista de Liberacion Nacional (EZLN), or Zapatista National Liberation Army, would bring the plight of Chiapan peasants to the attention of other Mexicans, foreign investors, and the international community, challenging anew the legitimacy of the Institutional Revolutionary Party (PRI), the long-standing ruling party of Mexico. While many revolutionary objectives have been attributed to the Zapatistas, the rebels admit that their publicly stated aims mask their most enduring claim against Mexico's authoritarian regime: freedom and relief from the escalating environmental scarcities that have been impoverishing their communities. By exploring the ecological history shared by the people and natural environment of Chiapas in this century, a better understanding emerges of some of the tangible, proximate sources for the grievances of the EZLN, the group responsible for organizing many of the ecologically marginalized poor of Chiapas into open rebellion. The changing supply and quality of soil and forest resources can be traced through social periods defined by the general principles under which state elites managed resources and manipulated property rights. From the Spanish Conquest until the Mexican Revolution, an almost feudal social order in Chiapas allowed state elites to capture resources as necessary. The revolution sought to stop this practice by redistributing land resources to peasants, but powerful elites in Chiapas still manipulated the resource regime as the competition for resources grew fierce and their supply dwindled. The Mexican debt crisis of the early 198os prompted an economic restructuring which allowed elites to be more aggressive, resulting in a large population of ecologically marginalized poor, some of whom organized the Zapatista Rebellion in 1994. The ecological marginalization of many

&lt;strong&gt;A boreal bryophyte community in a tropical montane forest of Mexico&lt;/strong&gt;

A Nowellia curvifolia community rich in boreal hepatics is reported from rotten logs in a pine forest in the central highlands of Chiapas, Mexico. The community is probably limited in the tropics to conifer forests of northern Mesoamerica. Nowellia curvifolia is reported as new to Brazil and the southern hemisphere, Cephalozia catenulata is new to Guatemala and Honduras and Cephalozia lunulifolia is new to Guatemala.

Incidence of the screwworm, Cochliomyia hominivorax, and the secondary screwworm, C. macellaria (Diptera: Calliphoridae), in the central highlands of Chiapas, Mexico.

In a 12-month survey in the central highlands of Chiapas (470 to 2,270 m elev.), 100 adult screwworms, Cochliomyia hominivorax (0.058 adults/trap-wk), and 1,155 adult C. macellaria (0.671 adults/trap-wk) were captured in wind-oriented traps baited with swormlure-2. Trap captures of these 2 species were not correlated with elevation; instead, adults appeared to occur in “pockets” along the altitudinal gradient. More adults of both species were captured during the wet season than in the dry season, and seasonal differences in captures were greater at elevations from 1,470 to 2,270 m than from 470 to 1,270 m. Adult capture rates (ACR) for screwworms were not correlated with average monthly temperature or rainfall at the low elevations but showed a positive correlation with average monthly temperature and rainfall at the high elevations. These differences in ACR between the high and low elevations were believed to be due to the greater annual changes in weather at the high elevations. ACRs for C. macellaria were not correlated with average monthly temperature or rainfall at either the high or low elevations. Screwworm oviposition showed a negative correlation with elevation (P < 0.05), a possibly significant negative correlation with average daily rainfall (P < 0.10), and a positive correlation with temperature (P < 0.05); however, oviposition was observed at the highest (2,060 m) and coldest (16.1 °C average daily temperature) sampling site.

Changing Patterns of Territorial Organization in the Central Highlands of Chiapas, Mexico

AbstractThe results of seven months of archaeological reconnaissance in the Tzeltal-Tzotzil-speaking area of Chiapas are described. Occupation is found to have consisted only of a few, small, widely dispersed centers during the Preclassic period. During the latter part of the Early Classic period there is evidence of a considerable increase in population, and by Late Classic times nucleated ceremonial-dwelling centers were widely distributed on steep, easily defended headlands. Despite great variation in the size of individual settlements, it is argued that independent communities rather than regional coalitions were the prevailing form of socio-political organization. This pattern was replaced gradually during the Postclassic period by one in which more intensive use was made of the larger, more strategically located valleys. Closely spaced, functionally interdependent groups of communities emerged, and probably were increasingly subject to new and more coercive patterns of political, as well as religious, control. At the time of the Spanish conquest hostilities and trade with other Mesoamerican groups were increasing rapidly, but the region as a whole still remained relatively tarriant and isolated.