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Deadwood is a large global carbon store with its store size partially determined by biotic decay. Microbial wood decay rates are known to respond to changing temperature and precipitation. Termites are also important decomposers in the tropics but are less well studied. An understanding of their climate sensitivities is needed to estimate climate change effects on wood carbon pools. Using data from 133 sites spanning six continents, we found that termite wood discovery and consumption were highly sensitive to temperature (with decay increasing >6.8 times per 10°C increase in temperature)—even more so than microbes. Termite decay effects were greatest in tropical seasonal forests, tropical savannas, and subtropical deserts. With tropicalization (i.e., warming shifts to tropical climates), termite wood decay will likely increase as termites access more of Earth’s surface. This study received support from the following sources: US National Science Foundation (NSF) DEB-1655759 (A.E.Z.); US NSF DEB-2149151 (A.E.Z.); US NSF DEB-1713502 (M.A.); US NSF DEB-1713435 (M.A.); US NSF DEB-1647502 (N.A.B.); US NSF DEB-1546686 (G.G.); US NSF DEB-1831952 (G.G.); George Washington University (A.E.Z.); USDA Forest Service (G.G.); Centre College Faculty Development Funds (M.L.G.); Australia Terrestrial Ecosystem Research Network National Collaborative Research Infrastructure Strategy (P.R.G., M.K., M.L., M.M.B., R.P.S., J.S., L.B.H., M.N., S.M.P., T.J.W., and S.K.A.); Royal Society-FCDO Africa Capacity Building Initiative (C.L.P., G.W.Q., S.A.-B., K.B., F.E.O., and M.P.R.); New Phytologist Foundation (A.T.A.); Fondecyt grant 1160329 (C.D.); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Brasil (CAPES) (E.v.d.B., A.S.Mou., R.F.M., F.F.S., T.M.C.-S., R.S.O., and A.M.D.); Department of Ecology and Conservation of the Federal University of Lavras (T.M.C.-S.); CNPq (E.v.d.B. and R.S.O.); FAPEMIG (E.v.d.B.); Australian Academy of Science 2017 Thomas Davies Research Grant (J.R.P.); Australian Research Council DP160103765 (W.K.C., J.R.P., and A.E.Z.); UK National Environment Research Council NE/L000016/1 (L.A.A.); Fundação de Amparo à Pesquisa do Estado de São Paulo, Brazil NERC - FAPESP 19/07773-1 (R.S.O. and A.M.D.); Environment Research and Technology Development Fund ERTDF, JPMEERF15S11420 of the Environmental Restoration and Conservation Agency of Japan (A.S.Mor. and K.O.); COLCIENCIAS no. FP44842-046-2017 (J.M.P.); Spanish government PID2019-110521GB-I00 (J.Pe., G.P., and R.O.); Catalan government grant SGR 2017-1005 (J.Pe., G.P., and R.O.); Fundación Ramón Areces ELEMENTAL-CLIMATE (J.Pe., G.P., and R.O.); National Agency for the Promotion of Research, Technological Development and Innovation, Scientific and Technological Research Project 2018-01561 PICT 2018-01561 (F.P.T.); ANID PIA/BASAL FB210006 (A.Fa.); Millennium Science Initiative Program NCN2021-050 (A.Fa.); iDiv German Research Foundation DFG–FZT 118, 202548816 (N.E.); and European Research Council Horizon 2020 research and innovation program no. 677232 (N.E.).

Deadwood is a large global carbon store with its store size partially determined by biotic decay. Microbial wood decay rates are known to respond to changing temperature and precipitation. Termites are also important decomposers in the tropics but are less well studied. An understanding of their climate sensitivities is needed to estimate climate change effects on wood carbon pools. Using data from 133 sites spanning six continents, we found that termite wood discovery and consumption were highly sensitive to temperature (with decay increasing >6.8 times per 10°C increase in temperature)—even more so than microbes. Termite decay effects were greatest in tropical seasonal forests, tropical savannas, and subtropical deserts. With tropicalization (i.e., warming shifts to tropical climates), termite wood decay will likely increase as termites access more of Earth's surface.

Existen numerosos mapas de la vegetación espontánea de la Argentina. Sin embargo, no contamos aún con uno de todo el país con una resolución que permita distinguir unidades de vegetación dentro de las provincias fitogeográficas descriptas por Cabrera (1976). Analizamos las descripciones de vegetación publicadas en las últimas décadas, con especial atención sobre aquellas que produjeron mapas fisonómico-florísticos. Como resultado de ese análisis, presentamos aquí un mapa fisonómico-florístico de la vegetación espontánea de la Argentina que muestra la heterogeneidad dentro de provincias fitogeográficas. El mapa tiene 50 unidades de vegetación como subdivisiones de las provincias fitogeográficas y el ecotono descritos con anterioridad, acompañadas de una breve descripción de la fisonomía y composición florística. Proponemos una nomenclatura de las unidades de vegetación según el tipo de vegetación espontánea dominante y especies características, y presentamos material cartográfico electrónico. There are numerous maps of the spontaneous vegetation of Argentina. However, a country-level map with enough detail to discriminate vegetation units within the phytogeographic provinces described by Cabrera (1976) is lacking. We analyzed vegetation descriptions published in recent decades, with special attention to those that produced physiognomic-floristic maps. As a result of this analysis, here we present a physiognomic-floristic map of spontaneous vegetation of Argentina that shows the heterogeneity within phytogeographic provinces. The map has 50 vegetation units as subdivisions of the phytogeographic ecotone and provinces early described, and a brief physiognomic-floristic description of each ecotone, province and vegetation unit. We propose a nomenclature of each vegetation unit based on dominant type of spontaneous vegetation and characteristic species and present digital cartographic material.

Las especies exóticas pueden impactar en el proceso de descomposición, ya sea de manera directa (diferencias en calidad y/o cantidad de hojarasca) o de manera indirecta (modificando las condiciones micro ambientales y la abundancia y/o actividad de descomponedores). Los objetivos de este trabajo fueron: I) comparar la descomponibilidad de las especies exóticas y nativas más abundantes de los bosques secundarios del pedemonte de la Sierra de San Javier, Tucumán, II) analizar el efecto de las condiciones micro ambientales sobre la tasa de descomposición de un sustrato común y III) evaluar el efecto del tamaño de malla de las bolsas de descomposición en la descomposición de hojarasca. Para ello incubamos hojarasca de 7 especies nativas y 7 exóticas bajo condiciones estándares durante un año y hojarasca de Populus deltoides (sustrato común) en parches de bosques secundarios nativos e invadidos por Ligustrum lucidum en bolsas con dos tamaños de malla. La pérdida de peso no fue diferente entre el conjunto de especies nativas y exóticas pero si se encontraron diferencias interespecíficas. La constante de descomposición del sustrato común fue menor en los bosques invadidos por lo que L. lucidum modificaría la composición y/o actividad de organismos descomponedores y generaría cambios en las condiciones micro ambientales que determinan la descomposición. Por otra parte, la descomposición fue mayor en bolsas con malla grande, lo cual podría deberse al acceso de macro invertebrados. Nuestros resultados sugieren la ausencia de un patrón de descomposición en el conjunto de especies nativas y exóticas y la potencial influencia que tendría L. lucidum en los factores que controlan la descomposición. Exotic species may influence the process of decomposition, either directly (through differences in the quality and/or quantity of leaf-litter) or indirectly (by altering microclimatic conditions and the abundance and/or activity of decomposers). The aims of our study were: I) to compare the decomposability of the most abundant exotic and native species in secondary forests of the Sierra de San Javier, Tucumán, II) to assess the effect of microenvironemtal conditions on the rate of decomposition of an homogeneous substrate and III) to evaluate the effect of the litterbags mesh size on the decomposition process. To do this, we incubated leaf-litter of 7 native and 7 exotic species under standard conditions for one year and also leaf-litter of Populus deltoides (homogeneous substrate) in native and invaded by Ligustrum lucidum secondary forest patches in bags with two mesh sizes. Native and exotic species did not differ in their weight loss rates, but there were interspecific differences. The decay constant of the homogeneous substrate was lower in invaded patches so it is possible that L. lucidum modify the composition and /or activity of decomposing organisms and generate changes in micro-environmental conditions. In addition, decomposition was higher in bags with larger mesh size. This pattern may be explained by the differential access of macro invertebrates. Our results suggest the absence of a pattern of decay in native and exotic species as groups, and the potential influence that L. lucidum would have over the factors controlling littler decomposition. Fil: Fernandez, Romina Daiana. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales E Instituto Miguel Lillo. Instituto de Ecología Regional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Aragón, Roxana. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales E Instituto Miguel Lillo. Instituto de Ecología Regional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Evaluamos el efecto de una ruta como inhibidora del desplazamiento de las aves, dentro de La Reserva Provincial La Florida (Tucumán, Argentina). Esta ruta divide la reserva, separando un fragmento del resto del bosque. Durante 12 meses realizamos muestreos mensuales de aves con redes de niebla instaladas a ambos lados de la ruta, y censamos las aves que atraviesan la ruta. Los individuos capturados fueron clasificados en sedentarios (capturados más de una vez) y transeúntes (1 captura). Si la ruta inhibe la llegada de nuevos individuos al fragmento (FG), el porcentaje de aves sedentarias en este sitio debería ser mayor que en el bosque continuo (BC). En las redes capturamos 1742 aves (34 especies); la riqueza fue similar para ambos sitios (27 vs. 28). El número de sedentarios no mostró diferencias entre sitios (BC=234, FG=194), al igual que el porcentaje mensual de aves sedentarias capturadas. Los transeúntes fueron más abundantes en el BC (809 vs. 505); la abundancia de Turdus rufiventris fue responsable de esta diferencia. En los censos en la ruta observamos 622 aves (28 especies). La cantidad de registros de T. rufiventris cruzando la ruta (33.8% del total de aves censadas) indicaría que esta barrera no afecta sus desplazamientos. Algunas especies frecuentes en las redes, fueron poco o no fueron detectadas cruzando la ruta, sugiriendo que sus desplazamientos podrían estar inhibidos por la ruta. Sin embargó, ninguna de estas especies mostró diferencias entre sitios en el porcentaje de aves sedentarias capturadas mensualmente. Los resultados de este trabajo sugieren que las aves estudiadas no están significativamente afectadas por la discontinuidad producida por la ruta. Estos resultados podrían no ser extrapolables a otras áreas de bosque, que requirirían estudios propios. We studied the effect of a road on bird movements at La Florida Provincial Reserve (Tucumán, Argentina). A road cuts the reserve leaving a forest fragment detached from the continuous forest. Understory birds were captured monthly for 12 months using 12-15 mist nets located in forest sites on both sides of the road, and birds crossing the road were censused to estimate movement between the fragment (FG) and the continuous forest (CF). The captured birds were classified as site-attached (captured more than once) and transient individuals (one capture). If the road reduced the arrival of new individuals into the FG, the proportion of site-attached captures would be expected to be larger here than in the CF. We captured 1742 birds (34 species). Richness was similar for both sites (CF=27, FG=28). Site-attached abundance showed no differences between sites (CF=234, FG= 194), as well as the percentage of site-attached birds captured monthly. Transient individuals were significantly more abundant in continuous forest (809 vs. 505); Turdus rujiventris abundance was responsible for this difference. In censuses we observed 622 individuals (28 species). The high frequency of T. rujiventris individuals crossing the road (33.8% from total birds censused) suggests that this barrier should not affect their movements. Some species commonly captured in the nets were not detected crossing the road, suggesting that they may be affected by the road. However, none of these species showed differences between sites in the percentage of site-attached captured monthly. Finally, our results suggest that understory birds are not significantly affected by the discontinuity produced by the road. These results could not always be extrapolated to other forests, that would require particular studies.

Currently biological invasions are considered one of the world’s most serious conservation problems. Ligustrum lucidum is the most abundant exotic tree in secondary forest patches of montane forests of NW Argentina. We studied the determinants of success of the early stages of its life cycle in distinct habitat types, with the hope of identifying vulnerabilities that could be exploited to control the invasion. Seed arrival, germination, seedling recruitment and survival, and sapling growth were studied in edges, gaps and forest interior. Seed arrival was also assessed under perches and in open fields. Germination was studied in forest and grass-land patches. L. lucidum seedling survival and sapling growth were compared with the most abundant native species survival and growth. Seed arrival was strongly seasonal with a peak in mid-August. Seed rain did not differ significantly among habitat types, however there was a tendency for edges to receive more seeds when only dispersed seeds were considered. Perches strongly enhanced seed arrival; more than 40 times the number of seeds were dispersed beneath citrus plants (i.e. perches) than found in paired open areas. In the forest, seeds in gaps and edges had higher germination rates, but there was no difference in seedling survival. Fruits under closed canopy exhibited the lowest germination. Germination and survival were low in open areas. Neither seedling recruitment nor sapling growth differed between gaps and forest interior. L. lucidum saplings grew significantly more than saplings of the most common native species, and also showed higher seedling survival. L. lucidum is a prolific fruit producer, is capable of germinating and surviving in a broad range of forest environments, it is relatively shade tolerant and has higher survival and faster growth rate in comprison to the most common native species. All these characteristics highlight its potency as a successful invader, and point to few vulnerabilities that could be targets of control measures.Las invasiones biológicas son consideradas actualmente uno de los problemas de conservación más serios. Ligustrum lucidum es el árbol exótico mas abundante en los bosques secundarios del NO de Argentina. Estudiamos llegada de semillas, germinación, reclutamiento y crecimiento de renovales en claros, bordes e interior del bosque La llegada de semillas también se estudió bajo perchas y en sitios abiertos. La supervivencia y el crecimiento de renovales de L. lucidum fueron comparados con los de las especies nativas mas abundantes. El arribo de semillas fue estacional y los bordes mostraron una tendencia a recibir mas semillas dispersadas. La presencia de perchas aumentó la llegada de semillas. Dentro del bosque, las semillas germinaron mas en claros y bordes, pero no hubo diferencia en sobrevivencia. La germinación y la supervivencia fue baja en sitios abiertos. El reclutamiento y crecimiento de renovales no difirió entre claros e interior del bosque. Los renovales de L. lucidum crecieron mas que los renovales de las especies nativas mas comunes. L. lucidum se establece y sobrevive en un amplio rango de condiciones, es relativamente tolerante a la sombra y tiene una rápida tasa de crecimiento. Estas características indican su capacidad invasora, y señalan escasas vulnerabilidades que puedan ser usadas para su control.