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[Introducción]: La restauración ecológica es una prioridad global para recuperar la biodiversidad y alcanzar los Objetivos de Desarrollo Sostenible. Desde su creación en el año 2000, la Reserva Natural Madre Verde —en Costa Rica— ha sido un modelo en este sentido. En 2005 se realizó una caracterización de las comunidades vegetales presentes: pastizal, charral, cultivo abandonado, área dominada por burío, bosque secundario denso, bosque secundario ralo y dos remanentes de bosque maduro. [Objetivo]: En 2020, se repitió el estudio, excluyendo los remanentes de bosque maduro, con el fin de evaluar los cambios en la vegetación después de 15 años de restauración. [Metodología]: Se identificaron las especies de árboles, se calcularon índices de riqueza y diversidad y se elaboraron perfiles de vegetación en cada tipo de comunidad. [Resultados]: Los mayores cambios en los índices de riqueza y diversidad, composición y estructura vertical de la vegetación se observaron en las zonas de pastizal que fueron sometidas a reforestación activa. Además, se registraron cambios importantes en el charral y en la zona dominada por burío. Los menores cambios se dieron donde ya existía algún tipo de bosque secundario relativamente maduro debido a la sombra creada por los árboles. [Conclusiones]: En todos los sitios predominan las especies pioneras nativas de esta zona de vida, lo que garantiza el proceso natural de regeneración. Estos resultados permiten conocer los avances en la restauración y saber cuáles son las especies más adecuadas para reforestar otras áreas similares y asegurar la recuperación del bosque secundario de manera más rápida y efectiva.

The study was carried out in a fragment of the mesophilic semideciduous Forest of the Guisa Agroforestry Experimental Station, with the objective of chemically characterizing the forest floor along a profile. In its three transects were drawn in the sense of the toposequence (base, slope and summit). In each transect 9 samples were taken (from 0-20 cm) for their chemical analysis. Multiple means comparison tests were applied, through the Tukey HDS test (p≤0.05%). Likewise, a linear regression analysis was developed and a correspondence analysis was carried out, in order to evaluate the interrelations among the chemical variables of the soil. The results indicated soils with high base saturation, low acidity and high concentration of Ca, especially at the slope and top levels. Brown soils with carbonates were identified in the base, and red Fersialitic and Redzina in the slope and the top. The Ca and P elements showed the greatest differences in the three topographic levels.

In order to determine the diversity of permanent resident birds associated with a natural pine forest of Pinus tropicalis and its relationship with the vertical structure of the vegetation; 30 circular plots were established in a natural forest of Pinus tropicalis of the locality Tibisí, of the Agroforestry Mines Company. All the birds seen or heard in each sample unit were inventoried, according to the vegetation strata (high, medium and low). The inventoried birds were classified according to endemism, threat, trophic groups. The alpha diversity of the species was determined by interpreting the range-abundance curve, the smoothed curves of estimated species accumulation according to the nonparametric estimators based on abundance (CHAO 1, ACE and Cole). The frequency of observation of the individuals in each stratum was determined. The Kruskall-Wallis nonparametric variance analysis was applied to determine if there were differences between the abundance values of the birds detected and the strata; In addition, the Mann-Witney and Wilcoxon tests were used to establish between those who were the differences. In the studied pine forest 32 species of permanent resident birds were inventoried, of which 9 are endemic and 5 are endangered. The majority of the birds detected are trophically insectivorous. There were significant differences between the strata occupied by them, in relation to the abundance of the same; being in a greater proportion in the high stratum, followed by the medium and finally the low one.

around Abra Apacheta, in Cangallo (Ayacucho) and Huaytara (Huancavelica) Provinces. The aims of this study were: to study vascular floristic composition of High Andes (over 4500 m of altitude) and characterize highland vegetation. There were used conventional techniques for botanical collection and vegetation coverage measurements by intersection-line transects and Point Quadrat modifyed method. There were registered 134 species of vascular plants (Pteridophytes, Gymnospems, Eudicots and Monocots) grouped in 60 genera and 23 families. Eudicots were the dominant group with 74% of the total registered, 82% in genera and 77% in species; followed by Monocots with 13%, 13% and 21% in the previous categories. Monilophytes (ferns) were poorly represented by two families (9%), two genera (3%) and two species (1%); while Gymnosperms only registered one specie (Ephedra rupestris Benth.). By the quantitative analysis three types of plant communities associated to cryoturbated soils were characterized, we also report two types of associated vegetation: grasslands and rocky areas.

En el avance del uso de teledetección como método para determinar la dinámica de incendios en el país y como complemento a trabajos desarrollados a nivel nacional, se analizó la distribución temporal y espacial de incendios y coberturas vegetales del departamento de Cundinamarca, la ciudad de Bogotá D.C y en las diferentes categorías de conservación y manejo, en los últimos 10 años. A partir de datos procesados por FIRMS y analizados en ArcGIS 10 y PSAW Stadistics 18, se encontró que los incendios en el área de estudio se mantienen dentro del patrón nacional, destacando además que la incidencia es causada por la poca precipitación y la intervención del hombre en espacios naturales. Las poblaciones más afectadas son Caparrapí 159 incendios, Bogotá 152 incendios y Guaduas 101 incendios. Bogotá registra la mayoría de sus incendios en la parte sur, en la localidad de Sumapaz. En cuanto a áreas protegidas del departamento el Parque Nacional Natural Sumapaz con 84 registros encabeza, seguido por el Distrito de Manejo Integrado Cuchilla de San Antonio con 21 registros y la Reserva Forestal Protectora Paramo Grande con 9 nueve registros. Entre la vegetación afectada se destacan los pastos, arbustos, matorrales y sus mosaicos, resaltando alto valores de incidencia sobre la vegetación de paramo y subpáramo. Las partes centro y noroccidentales, sur y surorientales, del departamento, son las que presentan más conflagraciones, y que en su mayoría se ubican entre los 0 a 1000 msnm y 3000 a 4000 msnm.

Agri-environment schemes are an instrument used by western European countries to counteract the negative effects of contemporary agriculture on biodiversity, but not much is known about their effectiveness. We investigated the ecological effects of Dutch agri-environment schemes aimed at promoting botanical diversity or meadow birds, and we tested whether the effectiveness of the schemes depends on landscape type or structure. In three different types of landscape, we surveyed plants, birds, bees, and hover flies on 78 paired fields that either had agri-environment schemes or were managed conventionally, and we collected data on a range of different environmental variables. Neither plant species richness nor abundance of meadow birds was higher on fields with agri-environment schemes. Landscape type had a significant effect on both species groups, but the effects of the schemes were independent of landscape type. Neither the diversity of plants nor the abundance of birds was related to any of the environmental variables. Agri-environment schemes designed to promote plant species richness or bird abundance did have positive side-effects because they enhanced the species richness of bees and hover flies, irrespective of the type of landscape. Furthermore, landscape type, groundwater level (hover flies), and area of wooded edges (bees) significantly affected both species groups. The failure of the schemes to promote the target species may be related to the high intensity of land use in The Netherlands. Simple conservation measures taken by farmers may not be sufficient to counteract the impact of factors that are often controlled at the landscape level (e.g., hydrology). Similar studies in other countries are needed to place the results of our study into a European context. [ABSTRACT FROM AUTHOR]

El páramo de Frontino, representa un medio de alto contraste en sus parámetros climáticos por lo que su vegetación tiene características xerofiticas. En estos ecosistemas las condiciones ambientales son drásticas y opera un tipo de selección abiótica; los organismos que han logrado adaptarse a estas situaciones, son condicionados por factores climáticos, edafológicos y geomorfológicos. La mayoría de las plantas analizadas producen fitolitos, de ellas, ca/amagrostis ejfusa, fue la especie más dominante, seguida de lycopodium a/ opecuroides, espeletia frontinoensis e hypericum juniperinum. La morfotribu más dominante es la prismatolita, que está íntimamente relacionada con halteriolita y doliolita. Flabellulita es muy común en los suelos, sin embargo, en las especies vegetales esta solo se reporto en pequeñas cantidades en blecnhum, disterigma, paepalanthus y chusquea.