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Most reforestation in Colombia, especially in the Andean region, are monocultures of pines and eucalyptus with defined nursery and silvicultural packages. Planting native species would avoid the widespread controversy over reforestation with exotic species. Nevertheless, there are few studies that evaluate the growth and yield of native species and provide supported data to establish new projects. Here, we modeled the growth and yield of the native coniferous Retrophyllum rospigliosii in different areas of the Colombian Andes in terms of mean diameter (D), height (H), and volume (V) as a function of age, based on longitudinal data from 115 research sample plots from three sites that were remeasured between 4 and 9 times for 20 years. We fitted the von Bertalanffy growth model for D, H, and V through Bayesian generalized nonlinear mixed models to model tree growth. The adjustment of the models for the absolute growth of R. rospigliosii was 0.99, 0.99, and 0.97 for D, H, and V, respectively. All models fulfilled all regression assumptions. Although the growth rates of R. rospigliosii differed between planted sites, R. rospigliosii plantations generally exhibited low growth and barely reached the sizes required for commercialization. These results suggest that the extensive use of R. rospigliosii in pure plantations is unlikely and discourages the massive propagation of R. rospigliosii. [ABSTRACT FROM AUTHOR]

Iturbide is in the northeast of Mexico and has a rich native and exotic flora; however, there are no ethnobotanical records, therefore, it requires attention in the documentation of traditional knowledge and practices of its botanical resources. In 2021, twelve field trips were carried out, applying 110 semi-structured interviews. Plant samples were collected, identified and deposited in an herbarium. We used the Chi-square test to compare the anthropocentric categories concerning others reported in Mexico. To determine the cultural importance, three ethnobotanical indices were applied (UVI, ICF and FL). We recorded 250 species with ethnobotanical implications associated with 121 genera and 83 families, including 140 native and 110 exotic species. The most common plant families were Asteraceae, Lamiaceae and Fabaceae. The main categories of uses were: ornamental, medicinal and food. The species with the highest UVI values were Lepidium peruvianum, Ocimum basilicum and Salvia rosamrinus. The multifunctionality of the native and exotic flora demonstrates the extensive knowledge associated with botanical resources. For example, the role of ornamental plants, with a direct impact on human well-being, the resilience of healers and traditional inhabitants by using different species for the treatment of various ailments or indigenous edible plants in the daily diet. [ABSTRACT FROM AUTHOR]

Pest infestation is one of the critical biotic threats to mangrove ecosystem stability. Early observations of infestation-induced damage and plant resistance could reveal the initial status of insect attacks. However, the differences between the pest resistance of native and exotic mangrove species remain poorly addressed. Here, we collected leaf photosynthetic, nutritional, morphological, and optical traits from four native and two exotic mangrove species in a subtropical mangrove ecosystem under healthy and infested conditions. Interspecific differences in resistance to pest infestation were assessed based on trait and spectral susceptibility. The results showed that photosynthetic pigments and anthocyanin correlated significantly with the health status of mangrove species. Chlorophyll a, chlorophyll b, and total chlorophyll contents in native species decreased significantly after infestation compared to those in exotic species, which led to consequent decreases in red-edge range reflectivity. Our findings demonstrate that both exotic species, Sonneratia apetala, and Sonneratia caseolaris , have much higher resistance to pest infestation than native species. • Photosynthetic pigments reflect health status of both native and exotic mangrove species. • The two exotic species had higher resistance to pest infestation than native species. • Leaf spectroscopy revealed significant Chlorophyll a-related resistance within and between species. [ABSTRACT FROM AUTHOR]

Species‐specific herbivores are hypothesized to maintain plant diversity by preventing the dominance of any one plant species. However, a large proportion of herbivores have wide host ranges, and these generalists could have similar effects on plant community composition if they exhibit differences in their host preference. Here, we coupled laboratory and field experiments to test whether a common forest‐understorey snail (Neohelix alleni), a generalist herbivore, has the potential to influence forest composition through differential preference of their plant hosts.We first performed a cafeteria‐style experiment to test whether N. alleni showed feeding preferences among leaves of five tree species and one shrub common to temperate forests in Missouri, USA. We then conducted a factorial snail and deer exclusion experiment to decouple the effects of snail herbivory from those of white‐tailed deer on seedling establishment of 1‐month‐old newly germinated seedlings of these six woody species in the field. Finally, we examined whether variation in both snail feeding preference and experimentally measured effects of snails on seedling establishment across plant species were related to their relative abundance measured in a 12‐ha forest plot.In the laboratory, we found that snails preferred leaves of woody species that were less abundant in the forests relative to those species that were more common. In the forest, we found that experimental exclusion of snails had a stronger positive effect on seedling above‐ground biomass and survival over a 1‐year period than did exclusion of deer. Plant species found to be more preferred in the laboratory were also those that had lower seedling establishment in the forest due to the negative effects of snails.Synthesis. Collectively, our results suggest that greater susceptibility to snail herbivory limits seedling establishment, perhaps contributing to differences in tree species relative abundance. Although less appreciated than their insect and mammal counterparts, herbivory by snails may be significant drivers to the assembly of forest tree communities. [ABSTRACT FROM AUTHOR]

Abstract: Human land use causes major changes in species abundance and composition, yet native and exotic species can exhibit different responses to land use change. Native populations generally decline in human‐impacted habitats while exotic species often benefit. In this study, we assessed the effects of human land use on exotic and native reptile diversity, including functional diversity, which relates to the range of habitat use strategies in biotic communities. We surveyed 114 reptile communities from localities that varied in habitat structure and human impact level on two Caribbean islands, and calculated species richness, overall abundance, and evenness for every plot. Functional diversity indices were calculated using published trait data, which enabled us to detect signs of trait filtering associated with impacted habitats. Our results show that environmental variation among sampling plots was explained by two Principal Component Analysis (PCA) ordination axes related to habitat structure (i.e., forest or nonforest) and human impact level (i.e., addition of man‐made constructions such as roads and buildings). Several diversity indices were significantly correlated with the two PCA axes, but exotic and native species showed opposing responses. Native species reached the highest abundance in forests, while exotic species were absent in this habitat. Human impact was associated with an increase in exotic abundance and species richness, while native species showed no significant associations. Functional diversity was highest in nonforested environments on both islands, and further increased on St. Martin with the establishment of functionally unique exotic species in nonforested habitat. Habitat structure, rather than human impact, proved to be an important agent for environmental filtering of traits, causing divergent functional trait values across forested and nonforested environments. Our results illustrate the importance of considering various elements of land use when studying its impact on species diversity and the establishment and spread of exotic species. [ABSTRACT FROM AUTHOR]

Updated list of earthworms (Oligochaeta: Lumbricina) from Santa Fe (Argentina) is presented in this work, including current data of species richness and territorial distribution status and information collected by Ljungström and collaborators 40 years ago. Field samplings were conducted between 2012 and 2015 at 23 sites, located in 11 of the 19 districts of the province. Earthworms were collected following a standard methodology. The conservation of specimens was done with 4 % formalin solution and their identification was performed according to taxonomy keys. Richness, similarity and complementarity of species between the phytogeographic provinces were analyzed. A total of 15 earthworm species were identified and grouped into ten genera and five families: Acanthodrilidae (Dichogaster bolaui, Microscolex dubius), Glossoscolecidae (Glossodrilus parecis), Lumbricidae (Aporrectodea caliginosa, Aporrectodea rosea, Aporrectodea trapezoides, Bimastos parvus, Eisenia fetida, Octolasion tyrtaeum), Megascolecidae (Amynthas gracilis, Amynthas morrisi, Metaphire californica), Ocnerodrilidae (Eukerria saltensis, Eukerria rosae, Eukerria stagnalis). From all the species found five, G. parecis, E. saltensis, E. rosea, E. stagnalis and M. dubius, are native to South America, and the rest were introduced from Asia and Europe. The Espinal presented the greatest richness of earthworms (12), while the Pampeana showed high values of complementarity (greater than 70 %) with the Chaco Húmedo and Valle de Inundación del Río Paraná. Endogeic species were present in all environments surveyed. In particular, the exotic species A. trapezoides and A. morrisi showed a wide geographical distribution, having been found at 70 and 50 %, respectively, of the total number of the studied sites. One species, E. rosea, which is in the list, was not recorded in the sampling of 40 years ago. The results of current survey show that the number of species was lower compared to study by Ljungström and collaborators (60 % of the 23 species registered). Possibly the remarkable change in the richness and distribution of earthworms could be a process associated with changes in soil use and land management developed over 40 years. [ABSTRACT FROM AUTHOR]

Many efforts to restore disturbed landscapes seek to meet ecological goals over timescales from decades to centuries. It is thus crucial to know how different actions available to restoration practitioners may affect ecosystems in the long term, yet few such data exist. Here, we test the effects of seed and compost applications on plant community composition 9 years after their application, by taking advantage of a well-controlled restoration experiment on a mountainside severely degraded by over 80 years of zinc smelting emissions. We asked whether plots have converged on similar plant communities regardless of initial seed and compost treatments, or if these initial treatments have given rise to lasting differences in whole plant communities or in the richness and abundance of native, exotic, and planted species. We found that compost types significantly affected plant communities 9 years later, but seed mix species composition did not. Observed differences in species richness and vegetative cover were negatively correlated, and both were related to the differences in plant communities associated with different compost types. These observed differences are due primarily to the number and abundance of species not in original seed mixes, of which notably many are native. Our results underscore the importance of soils in shaping the aboveground composition of ecosystems. Differences in soil characteristics can affect plant diversity and cover, which are both common restoration targets. Even in highly polluted and devegetated sites, compost and seed application can reinstate high vegetative cover and allow continued colonization of native species. [ABSTRACT FROM AUTHOR]

This paper explores various attempts to manage predation threats to an endangered population of little penguins (Eudyptula minor) living in Sydney′s North Harbour. Some of these threats have come from species that are generally termed ′exotic′ (such as the red fox, Vulpes vulpes), while other threats have potentially come from ′natives′ (such as the New Zealand fur seal, Arctocephalus forsteri). This paper explores the problematic notion of ′invasiveness′ as it applies to native and introduced predators, and the role that these rhetorical distinctions play in positioning various species as ′threats′ to the continuity of this penguin colony. In particular, the paper is concerned with conservation legislation and practice in New South Wales, and the unique kind of ′ethical work′ done by these processes of classifying living things. Finally, the paper asks, in the absence of a simplistic-but helpful-correlation between exotic and invasive species, how might we understand and justify the conservation of an isolated colony of little penguins? What kinds of interventions (from humans and nonhumans) are warranted, and which are not? What might it mean to genuinely inhabit these difficulties, making conservation decisions outside of any space of simple and absolute answers?

Araucaria angustifolia, also known as the Paraná Pine is an endangered tree species in Brazil and little is known of the diversity of soil invertebrates inhabiting these forests. Therefore, the present study was set up to evaluate the biomass and diversity of earthworms in natural and reforested Araucaria plots, impacted or not by fire, and to identify the most efficient earthworm collection method. Four study areas included: native forest with Araucaria (NF); Araucaria reforestation (R); Araucaria reforestation submitted to an accidental fire (RF); and native grass pasture with native Araucaria and submitted to an intense accidental fire (NPF). Five soil samples containing the earthworm community were taken in a 0.3 ha area in each of the forest sites, close to five Araucaria trees selected at random. Three collection methods were tested: application of dilute Formol (0.5%) to the soil surface, handsorting of small (25 ´ 25 cm) or large (40´ 40 cm) monoliths. Five earthworm species were found: the native Glossoscolex sp.1, Glossoscolex sp.2, Glossoscolex bondari and Urobenus brasiliensis (Glossoscolecidae), and the exotic Amynthas corticis (Megascolecidae). Formol was more efficient for collecting A. corticis, found in much higher abundance and biomass in NF than in the other areas. Larger handsorted samples were more efficient for capturing Glossoscolex species, mainly present in RF and NPF. For adequate characterization of earthworm abundance and biomass in these Araucaria forests, both the Formol and the larger monolith methods are recommended.Araucaria angustifolia, também conhecida como Pinheiro do Paraná é uma espécie de árvore ameaçada de extinção no Brasil e pouco se conhece sobre a diversidade de invertebrados que habitam os solos destas florestas. O presente estudo teve o objetivo de avaliar, em florestas com araucária naturais e reflorestadas impactadas ou não pela queima acidental, a diversidade e a biomassa de minhocas, além de identificar o método mais eficiente para coletar estes animais. As áreas estudadas incluem: floresta nativa com araucária (NF); reflorestamento de araucária (R); reflorestamento de araucária submetido a incêndio acidental (RF); e campo nativo com araucárias nativas e ocorrência de incêndio (NPF). Em cada floresta, cinco amostras de solo para avaliação da comunidade de minhocas foram coletadas em 0,3 ha, perto de cinco árvores de araucária selecionadas ao acaso. Foram testados três métodos: aplicação de Formol diluído (0,5%) na superfície do solo; escavação e triagem manual de monólitos pequenos (25 ´ 25 cm) ou maiores (40 ´ 40 cm). Foram encontradas cinco espécies de minhocas, as nativas Glossoscolex sp.1, Glossoscolex sp.2, Glossoscolex bondari e Urobenus brasiliensis (Glossoscolecidae), e a exótica Amynthas corticis (Megascolecidae). Formol foi mais eficiente para coletar A. corticis espécie encontrada em maior abundância e biomassa fresca total em NF do que nas outras áreas. A triagem manual de amostras de solo maiores foi mais eficiente para capturar as espécies de Glossoscolex, presentes principalmente em RF e NPF. Formol e a triagem manual de monólitos maiores são recomendados para caracterizar a abundância e biomassa de minhocas nas florestas com araucárias.

We studied the riparian vegetation distributed across four watersheds in urban areas of Manaus, Amazonas—Brazil in order to compare native and exotic plant community patterns. In total, we investigated the woody plant communities in 31 urban streams. The transects established in each site were of an area 200 m long × 5 m wide parallel to the stream, giving a total study area of 3.1 ha. Exotic species accounted for 15% of the total of 126 species identified. Our results showed absence of significant differences in species richness and diversity between basins suggesting that vegetation of urban streams located near more urbanized areas is not yet seriously compromised. We found a low percentage of non-native species with relatively high woody species diversity. However, we recommend the correlation of variable such as ecological strategies, species lifespan, species richness, and species cover with environmental data to provide elements for impact assessment and the monitoring of these watersheds. [ABSTRACT FROM AUTHOR]

Acacia longifolia is an invasive woody legume in many coastal sand dunes ecosystems around the world. A useful option to aid in the restoration of invaded areas after acacia removal is the revegetation of the newly open areas using appropriate native dune plants. A field experiment was performed to determine whether two shrubby legumes native to European Atlantic coastal dunes, Cytisus grandiflorus (Brot.) DC. and Ulex europaeus europaeus subsp. latebracteatus (Mariz) Rothm., are suitable to revegetate areas formerly invaded by A. longifolia. Plants of both species were grown for 5 months in a greenhouse and subsequently transplanted to three sites in a coastal dune ecosystem. We monitored survival and growth during 21 months. The effect of soil fertility at the nursery and of root nodulation on the performance of these species in the field was also analyzed. Soil fertility and nodulation had a significant effect on plant growth at the nursery, but only the symbiosis with root nodulating bacteria had a significant positive effect on the survival of both native legumes in the field and on final plant height of U. europaeus plants. We conclude that (1) both native legumes can successfully establish on sites where A. longifolia has been previously removed, thus providing a suitable tool to help in the restoration of invaded areas, and (2) the symbiosis with root nodulating bacteria is crucial for plant performance in the field. [ABSTRACT FROM AUTHOR]

The potential differentiations in litter chemistry among native and non-native trees are poorly understood. We compared the chemical composition of leaf litterfall of 11 exotic tree species, e.g. coniferous: Abies cephalonica, A. grandis, A. procera, Chamaecyparis pisifera, Pinus peuce, Pseudotsuga menziesii, Thuja plicata, and deciduous: Acer rubrum, A. saccharum, Betula alleghaniensis and Quercus rubra, with that of a native European conifer, Pinus sylvestris (as reference to coniferous species) anda mixture of native European Quercus robur, Carpinus betulus, Tilia cordata, T. platyphyllos and Corylus avellana leaves (as a reference mixture of deciduous species). We found significant differences among the species studied in nitrogen and carbon content in needles/ leaves, C/N ratio, as well as total soluble phenolic compounds (TPh) and total nonstructural carbohydrates (TNC) content, including soluble carbohydrates and starch. However, we found no clear differentiation of exotic from native tree species in the analyzedelements andmetabolites. Among the exotic coniferous tree species, P. menziesii stood out among the species studied - fallen needles of this species were characterizedby relatively high TPh and TNC content. The relationships between TPh and TNC content in leaf and needle litter among tree species were similar among two consecutive years. For deciduous tree species, the tendency of higher TPh content and C/N ratio in leaves falling earlier (September; leaves of sun-type) than later (November; leaves of shade-type) was more distinct than in coniferous tree species. Generally, we cannot see any special differences in the levels or mutual quantitative relationships of the chemical compounds studied in fallen needles/leaves of exotic tree species in comparison with native tree species. [ABSTRACT FROM AUTHOR]

This paper explores various attempts to manage predation threats to an endangered population of little penguins (Eudyptula minor) living in Sydney's North Harbour. Some of these threats have come from species that are generally termed 'exotic' (such as the red fox, Vulpes vulpes), while other threats have potentially come from 'natives' (such as the New Zealand fur seal, Arctocephalus forsteri). This paper explores the problematic notion of 'invasiveness' as it applies to native and introduced predators, and the role that these rhetorical distinctions play in positioning various species as 'threats' to the continuity of this penguin colony. In particular, the paper is concerned with conservation legislation and practice in New South Wales, and the unique kind of 'ethical work' done by these processes of classifying living things. Finally, the paper asks, in the absence of a simplistic—but helpful—correlation between exotic and invasive species, how might we understand and justify the conservation of an isolated colony of little penguins? What kinds of interventions (from humans and nonhumans) are warranted, and which are not? What might it mean to genuinely inhabit these difficulties, making conservation decisions outside of any space of simple and absolute answers? [ABSTRACT FROM AUTHOR]