Vegetation structure and biodiversity recovery in 19-year-old active restoration plantations in a Neotropical cloud forest

Aim of the study: To evaluate how middle-aged active restoration plantations of native tree species contribute to the recovery of the tropical cloud forest in terms of vegetation structure, tree richness, species composition, and to shade-tolerance and seed dispersal mode functional groups.Area of the study: We studied two 19-year-old active restoration sites and their reference mature forests in the tropical montane cloud forest belt, Veracruz, Mexico.Materials and methods: The basal area, density and height as well as the tree species composition and number of species and individuals classified by shade tolerance (pioneer and non-pioneer trees), and seed dispersal mode (anemochorous, barochorous-synzoochorous and endozoochorous) were compared between active restoration plantations and reference forests.Main results: Planted trees and the woody vegetation growing under them represented a high proportion of reference forests’ basal area. Tree richness and Shannon’s equitability index were similar in both reference forests and one active restoration plantation and slightly different in the other. Tree species composition differed among sites; however, each 19-year-old plantation already had several non-pioneer species and a similar species proportion of the seed dispersal syndromes present in their reference forests.Research highlights: Active restoration accelerated the recovery of cloud forest in degraded pasture and bracken fern lands. Planted trees promoted the rapid development of vegetation structure and natural tree regeneration. Although species composition is still different, these middle-aged restoration plantations already have forest species and a proportion of functional groups of species similar to those of their own reference montane cloud forests.Keywords: active restoration; forest recovery; passive restoration; seed dispersal mode; succession; tree species; tropical montane cloud forest

Sequía experimental en plántulas en un claro y en el sotobosque de un bosque de niebla, Veracruz, México

Background and Aims: Droughts induced by climate change are expected to affect tropical cloud forests. As functional traits are useful indicators of plant species performance, this study aimed to determine the effect of light environment and drought on leaf area (LA), specific leaf area (SLA), chlorophyll content, leaf thickness and toughness, survival and relative growth rate (RGR) of seedlings in forest understory and gap. Methods: In a cloud forest from Veracruz, Mexico, rainout shelters to simulate drought in the forest understory and gap were used. Leaf area, SLA, chlorophyll content, leaf thickness and toughness, survival, and RGR in Eugenia capuli (shade-tolerant understory tree), Liquidambar styraciflua (intermediate shade-tolerant canopy tree), and Trema micranthum (pioneer tree that colonizes gaps) in understory-control and -drought, and gap-control and -drought were measured. Key results: Leaf area increased with drought in E. capuli in gaps and decreased in L. styraciflua in both light environments. Chlorophyll content was similar between water treatments for E. capuli and L. styraciflua in the understory. Leaf thickness and toughness differed with drought for E. capuli and L. styraciflua in the gap. Leaf traits of T. micranthum tended to change in understory and not in gap. Overall, the highest survival occurred in gap. Eugenia capuli displayed the highest and similar survival across treatments. Liquidambar styraciflua displayed higher survival in gap-drought, and T. micranthum in gap conditions. Eugenia capuli had the highest RGR in understory, whereas T. micranthum has the highest RGR in gap. Conclusions: Plant functional traits of E. capuli and L. styraciflua seedlings responded to moderate drought more in gap than in understory. The results suggest that functional traits of intermediate and shade-tolerant species may shift less under a moderate drought than those of a pioneer tree, as long as the forest light environment is maintained.Antecedentes y Objetivos: Se espera que las sequías inducidas por el cambio climático afecten al bosque de niebla. Como los rasgos funcionales son indicadores útiles del desempeño de especies vegetales, el objetivo de este trabajo fue determinar el efecto del ambiente lumínico y la sequía sobre área foliar (AF), área foliar específica (AFE), contenido de clorofila, grosor, dureza foliar, supervivencia y tasas de crecimiento relativo (TCR) de plántulas en sotobosque y claro. Métodos: En un bosque de niebla en Veracruz, México, se usaron exclusiones de lluvia para simular sequía en sotobosque y claro. Se midieron AF, AFE, contenido de clorofila, grosor, dureza, supervivencia y TCR en Eugenia capuli (especie de sotobosque tolerante a la sombra), Liquidambar styraciflua (especie del dosel de tolerancia intermedia) y Trema micranthum (árbol pionero colonizador de claros) en sotobosque-control y -sequía, y claro-control y -sequía. Resultados clave: El AF aumentó con sequía en E. capuli en claro y decreció para L. styraciflua en ambos ambientes lumínicos. El contenido de clorofila fue similar entre tratamientos de agua para E. capuli y L. styraciflua en sotobosque. El grosor y dureza foliares difirieron con sequía para E. capuli y L. styraciflua en claro. Los rasgos foliares de T. micranthum cambiaron solo en sotobosque. Eugenia capuli presentó la mayor y similar supervivencia entre tratamientos. Liquidambar styraciflua mostró una mayor supervivencia en claro-sequía, y T. micranthum en claro. Eugenia capuli tuvo la mayor TCR en sotobosque, mientras que T. micranthum en claro. Conclusiones: Los rasgos funcionales de plántulas de E. capuli y L. styraciflua respondieron a sequía moderada más en claro que en sotobosque. Los resultados sugieren que los rasgos funcionales de las especies intermedia y tolerante a la sombra tienden a cambiar menos bajo una sequía moderada, que los del árbol pionero si se mantiene el ambiente lumínico forestal

Toward integrated analysis of human impacts on forest biodiversity: lessons from Latin America.

Although sustainable forest management (SFM) has been widely adopted as a policy and management goal, high rates of forest loss and degradation are still occurring in many areas. Human activities such as logging, livestock husbandry, crop cultivation, infrastructural development, and use of fire are causing widespread loss of biodiversity, restricting progress toward SFM. In such situations, there is an urgent need for tools that can provide an integrated assessment of human impacts on forest biodiversity and that can support decision making related to forest use. This paper summarizes the experience gained by an international collaborative research effort spanning more than a decade, focusing on the tropical montane forests of Mexico and the temperate rain forests of southern South America, both of which are global conservation priorities. The lessons learned from this research are identified, specifically in relation to developing an integrated modeling framework for achieving SFM. Experience has highlighted a number of challenges that need to be overcome in such areas, including the lack of information regarding ecological processes and species characteristics and a lack of forest inventory data, which hinders model parameterization. Quantitative models are poorly developed for some ecological phenomena, such as edge effects and genetic diversity, limiting model integration. Establishment of participatory approaches to forest management is difficult, as a supportive institutional and policy environment is often lacking. However, experience to date suggests that the modeling toolkit approach suggested by Sturvetant et al. (2008) could be of value in such areas. Suggestions are made regarding desirable elements of such a toolkit to support participatory-research approaches in domains characterized by high uncertainty, including Bayesian Belief Networks, spatial multi-criteria analysis, and scenario planning.Most of the research described here was undertaken in three projects supported by the European Commission (INCO programme), namely SUCRE (ERBIC18CT970146), BIOCORES (ICA4- CT-2001-10095), and ReForLan (INCO-DEV-3 N° 032132), and three Darwin Initiative (DEFRA, UK Government) grants to the senior author. Additional funding was provided by a variety of sources within the partner countries. All sources of financial support are gratefully acknowledged

Toward integrated analysis of human impacts on forest biodiversity: lessons from Latin America.

Although sustainable forest management (SFM) has been widely adopted as a policy and management goal, high rates of forest loss and degradation are still occurring in many areas. Human activities such as logging, livestock husbandry, crop cultivation, infrastructural development, and use of fire are causing widespread loss of biodiversity, restricting progress toward SFM. In such situations, there is an urgent need for tools that can provide an integrated assessment of human impacts on forest biodiversity and that can support decision making related to forest use. This paper summarizes the experience gained by an international collaborative research effort spanning more than a decade, focusing on the tropical montane forests of Mexico and the temperate rain forests of southern South America, both of which are global conservation priorities. The lessons learned from this research are identified, specifically in relation to developing an integrated modeling framework for achieving SFM. Experience has highlighted a number of challenges that need to be overcome in such areas, including the lack of information regarding ecological processes and species characteristics and a lack of forest inventory data, which hinders model parameterization. Quantitative models are poorly developed for some ecological phenomena, such as edge effects and genetic diversity, limiting model integration. Establishment of participatory approaches to forest management is difficult, as a supportive institutional and policy environment is often lacking. However, experience to date suggests that the modeling toolkit approach suggested by Sturvetant et al. (2008) could be of value in such areas. Suggestions are made regarding desirable elements of such a toolkit to support participatory-research approaches in domains characterized by high uncertainty, including Bayesian Belief Networks, spatial multi-criteria analysis, and scenario planning.Most of the research described here was undertaken in three projects supported by the European Commission (INCO programme), namely SUCRE (ERBIC18CT970146), BIOCORES (ICA4- CT-2001-10095), and ReForLan (INCO-DEV-3 N° 032132), and three Darwin Initiative (DEFRA, UK Government) grants to the senior author. Additional funding was provided by a variety of sources within the partner countries. All sources of financial support are gratefully acknowledged

The Tree Biodiversity Network (BIOTREE-NET): prospects for biodiversity research and conservation in the Neotropics

Biodiversity research and conservation efforts in the tropics are hindered by the lack of knowledge of the assemblages found there, with many species undescribed or poorly known. Our initiative, the Tree Biodiversity Network (BIOTREE-NET), aims to address this problem by assembling georeferenced data from a wide range of sources, making these data easily accessible and easily queried, and promoting data sharing. The database (GIVD ID NA-00-002) currently comprises ca. 50,000 tree records of ca. 5,000 species (230 in the IUCN Red List) from \u3e2,000 forest plots in 11 countries. The focus is on trees because of their pivotal role in tropical forest ecosystems (which contain most of the world\u27s biodiversity) in terms of ecosystem function, carbon storage and effects on other species. BIOTREE-NET currently focuses on southern Mexico and Central America, but we aim to expand coverage to other parts of tropical America. The database is relational, comprising 12 linked data tables. We summarise its structure and contents. Key tables contain data on forest plots (including size, location and date(s) sampled), individual trees (including diameter, when available, and both recorded and standardised species name), species (including biological traits of each species) and the researchers who collected the data. Many types of queries are facilitated and species distribution modelling is enabled. Examining the data in BIOTREE-NET to date, we found an uneven distribution of data in space and across biomes, reflecting the general state of knowledge of the tropics. More than 90% of the data were collected since 1990 and plot size varies widely, but with most less than one hectare in size. A wide range of minimum sizes is used to define a \u27tree\u27. The database helps to identify gaps that need filling by further data collection and collation. The data can be publicly accessed through a web application at http://portal.biotreenet.com. Researchers are invited and encouraged to contribute data to BIOTREE-NET

La Red Internacional de Inventarios Forestales (BIOTREE-NET) en Mesoamérica: avances, retos y perspectivas futuras

Conservation efforts in Neotropical regions are often hindered by lack of data, since for many species there is a vacuum of information, and many species have not even been described yet. The International Network of Forest Inventory Plots (BIOTREE-NET) gathers and facilitates access to tree data from forest inventory plots in Mesoamerica, while encouraging data exchange between researchers, managers and conservationists. The information is organised and standardised into a single database that includes spatially explicit data. This article describes the scope and objectives of the network, its progress, and the challenges and future perspectives. The database includes above 50000 tree records of over 5000 species from more than 2000 plots distributed from southern Mexico through to Panama. Information is heterogeneous, both in nature and shape, as well as in the geographical coverage of inventory plots. The database has a relational structure, with 12 inter-connected tables that include information about plots, species names, dbh, and functional attributes of trees. A new system that corrects typographical errors and achieves taxonomic and nomenclatural standardization was developed using The Plant List (http://theplantlist.org/) as reference. Species distribution models have been computed for around 1700 species using different methods, and they will be publicly accessible through the web site in the future (http://portal.biotreenet.com). Although BIOTREE-NET has contributed to the development of improved species distribution models, its main potential lies, in our opinion, in studies at the community level. Finally, we emphasise the need to expand the network and encourage researchers willing to share data and to join the network and contribute to the generation of further knowledge about forest biodiversity in Neotropical regions

El bosque mesófilo de montaña, veinte años de investigación ecológica ¿qué hemos hecho y hacia dónde vamos?

Tropical montane cloud forest (TMCF) is a current issue. It would appear that TMCF had an extended tradition in ecological research, but it is only during the last 20 years that it has been intensively studied. The last 10 years have seen an impressive development in ecological knowledge and the emergence of several research lines. The objective of this paper is to present a review of the TMCF ecological research published in 1995-2014 to have a retrospective, a current view and a glimpse of future studies in Mexico and, particularly, in the state of Veracruz. Biodiversity and disturbance have been the most addressed issues in TMCF. In the last decade, following disturbance and habitat loss of the TMCF, more applied topics such as ecological restoration and ecosystem services have been consolidated. Forthcoming topics will be relating forest resilience with forest processes, components and climate change effects.El bosque mesófilo de montaña (BMM) es un tema de actualidad y, pareciera que con larga tradición de investigación ecológica pero el BMM, desde un punto de vista ecológico, ha empezado a estudiarse intensamente en los últimos 20 años con un impresionante desarrollo y despunte en varias áreas solamente en los últimos 10 años. El objetivo del presente artículo es presentar una revisión de 1995 a 2014 de varios temas de investigación para tener una retrospectiva, una visión actual y un vislumbre de hacia dónde se dirigen los estudios futuros de ecología del bosque mesófilo de montaña de México y particularmente en el bosque de Veracruz. Los temas más estudiados en el BMM están relacionados con biodiversidad y perturbaciones. En la última década se han consolidado temas prácticos que aparentemente tuvieron que esperar a que las condiciones de perturbación y destrucción del bosque los impulsaran, como son la restauración ecológica y los servicios ecosistémicos. Los temas a futuro deben relacionar la resiliencia del bosque, procesos y componentes ante los efectos del cambio climático

Microhabitat conditions for germination and establishment of two tree species in the mexican montane cloud forest

Las plantaciones mixtas de Carpinus caroliniana y Liquidambar styraciflua son apropiadas para rehabilitar áreas deforestadas en la región del bosque de niebla en Veracruz, México. Para determinar si la siembra directa de semilla puede usarse en actividades de restauración ecológica, se estudiaron algunas condiciones abióticas y bióticas para la germinación y el establecimiento de estas especies. Se evaluaron los efectos del micro habitat (interior del bosque, borde y claro), riego, y exclusión de herbívoros durante la germinación y desarrollo de las plántulas. Carpinus y Liquidambar tuvieron diferente porcentaje de germinación en el laboratorio (33 y 90%, respectivamente; p=0.001), en campo tuvieron un menor, pero también diferente porcentaje de germinación (26 y 18%, respectivamente, p=0.001), pero germinaron en los tres microambientes. La exclusión de herbívoros incrementó el porcentaje de germinación de ambas especies, particularmente de Carpinus (52%), mientras que Liquidambar tuvo 36%. Los resultados indican que la supervivencia de las plántulas y la tasa de crecimiento relativo son altas en el borde y claro, pero son mayores en los claros cuando hay agua disponible y exclusión de herbívoros. El método de siembra directa debe realizarse durante la estación húmeda (o regar) y con protección contra herbívoros