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The ecological niche concept has provided insights into various areas in ecology and biogeography. Although there remains much controversy regarding whether species niches are conserved across space and time, many recent studies have suggested that invasive species conserve their climatic niche between native and introduced ranges; however, whether the climatic niche of cultivated invasive species, whose niches are strongly affected by human activities, are conserved between native and introduced ranges remains unclear. Additionally, the range dynamics of invasive species in their native and introduced regions have not been extensively studied. Here, we investigated the niche and range dynamics of Tasmanian blue gum (Eucalyptus globulus Labill.), a globally cultivated invasive tree, using ecological niche models and niche dynamic analyses. The most important factors affecting the niche changes between native and introduced Tasmanian blue gum were max temperature of the warmest month and precipitation of the wettest month. The climate niche was not conserved between introduced and native range Tasmanian blue gum; moreover, the niche area of the former was ca. 7.4 times larger than that of the latter, as introduced Tasmanian blue gum could survive in hotter, colder, wetter, and drier climates. In addition, the potential range of introduced Tasmanian blue gum was ca. 32 times larger than that of its native counterpart. Human introduction and cultivation may play a key role in the niche and range expansion of introduced Tasmanian blue gum. Given that small increases in niche area can result in large range expansions, the niche expansion of an invasive species could be used to evaluate invasion risk, which might even be more sensitive than range expansions. The climate niche was conserved between introduced and native Tasmanian blue gum, though the niche breadth of the former was ca. 1.96 times wider than that of the latter. Small increases in niche breadth can result in large range expansions of Tasmanian blue gum.The niche expansion of an invasive species could be used to evaluate invasion risk, which might even be more sensitive than range expansion.

Aim The world's forested area has been declining, especially in developing countries. In contrast, forest plantations are increasing, particularly exotic Eucalyptus plantations, which cover nowadays over 20 million ha worldwide. This global landscape change affects native communities, especially those at higher trophic levels that are affected by bottom–up cascading effects, such as carnivores. We seek to identify the general life‐history traits of mammalian carnivore species that use exotic Eucalyptus plantations. Location We reviewed 55 studies reporting carnivore presence in Eucalyptus plantations worldwide. Methods We consider seven species life‐history traits (generation length, social behaviour, body mass, energetic trophic level, diet diversity, habitat generalist/specialist and locomotion mode) as candidate drivers. We used generalized linear mixed models, with life‐history traits as fixed factors, and study as well as carnivore species as random factors. We obtained the carnivore occurrence data from the literature (detection of 42 different species, from seven families). We considered non‐detected species those with an IUCN Red List of Threatened Species estimated distribution range overlapping with the study areas, but not recorded by the studies. Results While we found no evidence of an effect of any of the other life‐history traits tested, our modelling procedure indicated that habitat generalist species are more likely to use Eucalyptus forests than specialist species. Main conclusions Our results, therefore, confirm an impoverishment of predator communities in disturbed environments, with the exclusion of the most specialist predators, leading to fragmentation of their populations and, ultimately contributing to their local extinction. The local extinction of specialist carnivores may lead to “functional homogenization” of communities within plantations, modifying ecosystem functioning with a negative impact on plantations’ productivity, profitability and services.

The possible drivers and implications of an observed latitudinal cline in disease resistance of a host tree were examined. Mycosphaerella leaf disease (MLD) damage, caused by Teratosphaeria species, was assessed in five Eucalyptus globulus (Tasmanian blue gum) common garden trials containing open-pollinated progeny from 13 native-forest populations. Significant population and family within population variation in MLD resistance was detected, which was relatively stable across different combinations of trial sites, ages, seasons and epidemics. A distinct genetic-based latitudinal cline in MLD damage among host populations was evident. Two lines of evidence argue that the observed genetic-based latitudinal trend was the result of direct pathogen-imposed selection for MLD resistance. First, MLD damage was positively associated with temperature and negatively associated with a prediction of disease risk in the native environment of these populations; and, second, the quantitative inbreeding coefficient (QST) significantly exceeded neutral marker FST at the trial that exhibited the greatest MLD damage, suggesting that diversifying selection contributed to differentiation in MLD resistance among populations. This study highlights the potential for spatial variation in pathogen risk to drive adaptive differentiation across the geographic range of a foundation host tree species.

Key messageThe results presented here demonstrate the capacity for phloem sap as a diagnostic tool for monitoring the nutritional status of plants and highlight the processes of remobilisation and source–sink dynamics.It is essential to develop methods that accurately reflect plant nutritional status for growth. In a greenhouse experiment with potted eucalyptus, we studied the effects of withdrawing single macronutrients N, P, or K, or salt application on the abundance of components in phloem, xylem and leaves to identify and refine methods to rapidly and effectively assess the nutrient status of Eucalyptus globulus trees. Clear effects on growth (and photosynthesis) were found for “−N” treatment and NaCl application. Effects of nutrient withdrawal were detected indicating our methodologies are useful for nutrient availabilities below the threshold of growth responses. While “−P” resulted in significantly lower P in xylem sap, the corresponding effect for “−K” on K in xylem sap was not found, although Ca and Na increased. Salt application increased Na in xylem sap sixfold. In leaf material “−N” reduced N. Surprisingly, “+NaCl”, “−P” and “−K” did not change the corresponding elements in leaves. Additionally, “−P”-treatment had the tendency to affect C-, N-, K- and particularly P-increment (n.s.). In phloem sap, “+NaCl” resulted in several effects, most prominently doubling Na concentration. Importantly, “−N” increased amino acids in phloem sap (n.s.). Statistically significant relationships between concentrations in leaves and phloem sap were found for δ13C and amino acids. Within the results obtained from phloem sap, sugars and bivalent cations (Ca and Mg) are correlated with that obtained from the leaves as well as Na and P. The role and comparative advantages of phloem sap as a diagnostic tool for nutritional status are discussed.

The study was conducted to identify the self-incompatibility mechanism in Eucalyptus globulus ssp. globulus. Controlled self- and cross-pollinations were conducted on individual flowers from three mature trees that had self-incompatibility levels of 76, 99.6 and 100%. Flowers were harvested at 4, 6 and 8 weeks after pollination. Embryology was investigated by bright field microscopy on material harvested at 4 and 6 weeks after pollination. Fertilization had taken place at 4 weeks after pollination with zygotes and free nuclear endosperm visible. There was a greater proportion of healthy, fertilized ovules in the cross-compared with the self-pollination treatment, and approx, half the ovules examined from both pollen treatments were not fertilized or were degenerating. By 6 weeks after pollination a few zygotes were starting to divide. The number of healthy, fertilized ovules was still greater in the cross-pollination treatment, but the number of healthy fertilized ovules was lower in both treatments compared with 4 weeks after pollination, and many ovules were degenerating. Fertilized ovules were significantly larger than non-fertilized or degenerating ovules and this difference was detectable by eye at 6 and 8 weeks after pollination. The mechanism of self-incompatibility appears to have both late pre- and post-zygotic components.

Under laboratory test conditions commercial Labill. seed lots generally have a high level of viability and rapid, uniform germination. However, commercial nurseries occasionally report seed lots in which germination is spread over a period of up to 10 weeks. The present study examined apparent dormancy induction in seeds that were initially imbibed for periods ranging from 0 to 48 h in darkness followed by air drying and open storage for 1 week at 25°C±1°C. Germination tests were carried out in a 12 h light/12 h dark (12/12) photoperiod or in complete darkness. Longer periods of imbibition prior to drying reduced the percentage of seeds that germinated and slowed the rate of germination in seeds germinated under a 12/12 photoperiod. Seeds with the same pretreatment germinated normally in continuous darkness. These data suggest a previously unreported inducible, light-regulated dormancy in seeds.

This paper begins with a historical description of the processes of deforestation and establishment of forest plantations in Cotacachi, Ecuador. Then, to provide epistemological, geographical and cultural context for the study, the approach, methodology and field sites are detailed. It is argued that native and introduced plantation tree species ( ) often serve distinct purposes and, consequently, are valued for different reasons in the studied communities. While many community members recognize the potential ecological risks of monocultures of introduced tree species, they appreciate the trees' accessibility, utility and monetary value. Native trees, in contrast, are perceived to be very important ecologically and to provide economic benefits distinct from those of plantation species, but are also considered less accessible due to diminished quantities and reduced geographic distribution. This case study of perceptions of native and introduced trees demonstrates the difficulties and trade-offs inherent in the pursuit of conservation and development objectives in rural Andean communities.

This chapter presents the development of a tree survival probability equation and a tree diameter increment submodel, of the type potential function × modifier function. These two submodels are components of a wider modelling project to obtain an individual tree growth model for first-rotation plantations located in the north and central coastal regions of Portugal. The submodels are based on data from permanent plots and trials. The effects of competition on stand structure and tree growth were analysed, leading to the definition of different stages of stand development, according to the mean stand crown ratio. The hypothesis that different submodels are required to adequately describe growth at different stages of stand development was tested. This chapter also describes the full model, which also includes the following submodels: a dominant height growth equation, a tree crown ratio prediction equation, a tree height-diameter equation and a tree volume prediction equation.

Spain is divided in two main regions based on climatic parameters: Atlantic and Mediterranean. While silvopastoral systems are well established in Mediterranean areas, they are not widely used in the Atlantic area. The objective of this chapter is to evaluate the possibility of using silvopastoral systems in the Atlantic-influenced area of northern Spain, mainly in new plantations but also in old stands of coniferous and broadleaved species. The chapter describes the potential of silvopastoral systems using a range of species.

Silvopastoral systems are a form of multiple purpose land use, one function of which can be to reduce the risk of forest fires, which continue to be a threat to forests. In Spain, from 1991-2000 more than 175 000 ha were destroyed by fire annually, a third of this being woodland. Control of the undergrowth, which acts as a plant fuel for fire, should be made through prevention techniques that include cutting, controlled burning and controlled grazing. Grazing can also be a cause of fire, but when a suitable livestock breed is chosen and correctly managed, with animals which will reduce the understorey, it can prevent fires. These animals can also create income from meat production, as well as bringing other benefits, such as landscape enhancement, improved access and production of secondary products such as mushrooms. In long-term research in Galicia on this technique over four decades, encouraging trials have been conducted with goat, horse, sheep and pig grazing in , , and plantations. In this chapter, the key findings of this research will be presented alongside research on the same topic from elsewhere. Current research on grazing management of horses in a plantation showed that, in the medium term, control of understorey is important and there was no difference between continuous and rotational grazing.