Roberto Cazzolla Gatti

Trends in human development and environmental protection

Even if the will to follow a sustainable lifestyle in the Western countries is increasing, many developing countries are experiencing their phase of economic growth, threatening and overexploiting their environment. This study compares the Living Planet Index and the Human Development Index, and suggests that societies follow common patterns of development, from the indigenous lifestyle to undeveloped society, through a developing stage, towards a developed state. According to these common steps each society exploits local, regional and sometimes global natural resources to nourish its economic growth. If developing countries will not undertake strategies to skip the ‘intermediate’ stage of overexploitation of natural resources during their growing phase, Earth systems may not be able to keep alive the global biodiversity, and provide ecosystem services that sustain humanity.Even if the will to follow a sustainable lifestyle in the Western countries is increasing, many developing countries are experiencing their phase of economic growth, threatening and overexploiting their environment. This study compares the Living Planet Index and the Human Development Index, and suggests that societies follow common patterns of development, from the indigenous lifestyle to undeveloped society, through a developing stage, towards a developed state. According to these common steps each society exploits local, regional and sometimes global natural resources to nourish its economic growth. If developing countries will not undertake strategies to skip the ‘intermediate’ stage of overexploitation of natural resources during their growing phase, Earth systems may not be able to keep alive the global biodiversity, and provide ecosystem services that sustain humanity.

Climate change-induced salinity variation impacts on a stenoecious mangrove species in the Indian Sundarbans

The alterations in the salinity profile are an indirect, but potentially sensitive, indicator for detecting changes in precipitation, evaporation, river run-off, glacier retreat, and ice melt. These changes have a high impact on the growth of coastal plant species, such as mangroves. Here, we present estimates of the variability of salinity and the biomass of a stenoecious mangrove species (Heritiera fomes, commonly referred to as Sundari) in the aquatic subsystem of the lower Gangetic delta based on a dataset from 2004 to 2015. We highlight the impact of salinity alteration on the change in aboveground biomass of this endangered species that, due to different salinity profile in the western and central sectors of the lower Gangetic plain, shows an increase only in the former sector, where the salinity is dropping and low growth in the latter, where the salinity is increasing.

Exploring the relationship between canopy height and terrestrial plant diversity

A relatively small number of broad-scale patterns describe the distribution of biodiversity across the earth. All of them explore biodiversity focusing on a mono or bi-dimensional space. Conversely, the volume of the forests is rarely considered. In the present work, we tested a global correlation between vascular plant species richness (S) and average forest canopy height (H), the latter regarded as a proxy of volume, using the NASA product of Global Forest Canopy Height map and the global map of plant species diversity. We found a significant correlation between H and S both at global and macro-climate scales, with strongest confidence in the tropics. Hence, two different regression models were compared and discussed to provide a possible pattern of the H–S relation. We suggested that the volume of forest ecosystems should be considered in ecological studies as well as in planning and managing natural sites, although in this first attempt, we cannot definitively prove our hypothesis. Again, high-resolution spatial data could be highly important to confirm the H–S relation, even at different scales.

Freshwater biodiversity: a review of local and global threats

The total freshwater biodiversity is not fully known. In particular, freshwater invertebrates and microbes are poorly studied groups, and in tropical latitudes, that support most of the species of the world, the information is lacking. Although almost a hundred thousand of species live in fresh water, the species losses continue at the high rate and the probability of preserving much of the remaining biodiversity in fresh water seems to be very low. Freshwater ecosystems are increasingly influenced by multiple stressors that lead to loss of sensitive species and an overall reduction in diversity. Environmental change threatens freshwater biodiversity. This paper reports an extensive review of work that evaluates the current main threats for freshwater biodiversity, on a local and global scale.The total freshwater biodiversity is not fully known. In particular, freshwater invertebrates and microbes are poorly studied groups, and in tropical latitudes, that support most of the species of the world, the information is lacking. Although almost a hundred thousand of species live in fresh water, the species losses continue at the high rate and the probability of preserving much of the remaining biodiversity in fresh water seems to be very low. Freshwater ecosystems are increasingly influenced by multiple stressors that lead to loss of sensitive species and an overall reduction in diversity. Environmental change threatens freshwater biodiversity. This paper reports an extensive review of work that evaluates the current main threats for freshwater biodiversity, on a local and global scale.

A century of biodiversity: some open questions and some answers

The study the biodiversity is not just an attempt to understand the differences or similarities between species, habitats or genomes. It also includes an understanding of how nature regulates the processes that characterise ecosystems and ensure their functionality. It means as well to increase the ability to predict the impact of current and future anthropogenic actions on nature (Midgley et al. 2002). Biodiversity is what makes the Earth a unique planet. In the Universe, for all we know, or at least in our galaxy, life is the exception rather than the rule (Dick 1999). And even if a day when we are able to document the presence of living beings on other planets will come, this will also be an exception. The appearance of life is a phenomenon that has always fascinated mankind since without it, our human species would have never existed and no hairless biped would have studied life, with great admiration, and destroyed it with equal force (Cardinale et al. 2012). Species themselves are a mystery like the very existence of life (Wiley 1978). Why has evolution led to the ‘endless beautiful forms’, as Charles Robert Darwin called them, instead of letting one, amazingly adapted, dominate the evolutionary line? In recent years the advancement of ecological sciences allowed a better understanding of some fundamental biodiversity patterns (Gaston 2000). In less than a few decades most of the answers to the key issues about biological diversity have been enriched with new hypotheses and theories (Ricklefs 2004). However, many other questions are still open. Some (partially or completely) resolved questions about biodiversityISSN: 1488-8386 (Print) 2160-0651 (Online) Journal homepage: http://www.tandfonline.com/loi/tbid20 A century of biodiversity: some open questions and some answers Roberto Cazzolla Gatti To cite this article: Roberto Cazzolla Gatti (2017) A century of biodiversity: some open questions and some answers, Biodiversity, 18:4, 175-185, DOI: 10.1080/14888386.2017.1407257 To link to this article: https://doi.org/10.1080/14888386.2017.1407257

A sampling optimization analysis of soil‐bugs diversity (Crustacea, Isopoda, Oniscidea)

Abstract Biological diversity analysis is among the most informative approaches to describe communities and regional species compositions. Soil ecosystems include large numbers of invertebrates, among which soil bugs (Crustacea, Isopoda, Oniscidea) play significant ecological roles. The aim of this study was to provide advices to optimize the sampling effort, to efficiently monitor the diversity of this taxon, to analyze its seasonal patterns of species composition, and ultimately to understand better the coexistence of so many species over a relatively small area. Terrestrial isopods were collected at the Natural Reserve “Saline di Trapani e Paceco” (Italy), using pitfall traps monthly monitored over 2 years. We analyzed parameters of α‐ and β‐diversity and calculated a number of indexes and measures to disentangle diversity patterns. We also used various approaches to analyze changes in biodiversity over time, such as distributions of species abundances and accumulation and rarefaction curves. As concerns species richness and total abundance of individuals, spring resulted the best season to monitor Isopoda, to reduce sampling efforts, and to save resources without losing information, while in both years abundances were maximum between summer and autumn. This suggests that evaluations of β‐diversity are maximized if samples are first collected during the spring and then between summer and autumn. Sampling during these coupled seasons allows to collect a number of species close to the γ‐diversity (24 species) of the area. Finally, our results show that seasonal shifts in community composition (i.e., dynamic fluctuations in species abundances during the four seasons) may minimize competitive interactions, contribute to stabilize total abundances, and allow the coexistence of phylogenetically close species within the ecosystem.

Self-consciousness: beyond the looking-glass and what dogs found there

Self-recognition, that is, the recognition of one’s own self, has been studied mainly by examining animals’ and children’s responses to their reflections in mirrors (Gallup et al. 2002). The defini...Self-recognition, that is, the recognition of one’s own self, has been studied mainly by examining animals’ and children’s responses to their reflections in mirrors (Gallup et al. 2002). The definitive test is whether or not a subject is capable of using the reflection to notice and respond to a mark on the face, head or other parts of the body by touching the mark (Bard et al. 2006). The mark, which is placed on the subjects when they are distracted or under anaesthesia, is only visible to the subject when they look at themselves in a mirror. The basic idea behind the test is that the subject who understands the concepts of “self” and “others” can differentiate between the two, and can recognize himself in the reflection (Swartz et al. 1999). Based on these results other behavioural skills can be inferred, e.g. empathy (Bischof-Köhler 2012). Indeed, the capacity to differentiate one’s own self from others is often thought of as a prerequisite for understanding that someone else might be happy or sad, even if the beholder is not (Turner 1982). As a general pattern, studies agree that this response increases with age and could decline in old age (Bischof-Köhler 2012). However, the ability to recognize oneself in a mirror is an exceedingly rare capacity in the animal kingdom (Bekoff & Sherman 2004). Up to now, only great apes (including, of course, humans) have shown extremely convincing evidence of mirror self-recognition (Povinelli et al. 1993). Moreover, the mirror test can yield false negatives because if an individual fails the test it does not necessarily mean that the species is not self-conscious (Bekoff & Sherman 2004). The first evidence for self-awareness in a nonhuman species was experimentally demonstrated in the common chimpanzee (Gallup 1970), but numerous subsequent attempts showed no convincing evidence of self-recognition in a variety of other primates and non-primates, including monkeys, lesser apes, African gray parrots, one species of spider and elephants (Clark & Jackson 1994; Westergaard & Hyatt 1994; Pepperberg et al. 1995; Plotnik et al. 2006; Prior et al. 2008). All of these species demonstrate the ability to use a mirror to mediate or guide their behaviour. As of 2015, only the great apes (excluding gorillas), a single Asiatic elephant, dolphins, the Eurasian magpie and some ants (Cammaerts & Cammaerts 2015; Hill et al. 2015; Ma et al. 2015), have passed the mirror self-recognition (MSR) test. A wide range of species have been reported to fail the test, including gorillas, several monkey species, giant pandas, sea lions, pigeons and dogs (Delfour & Marten 2001; Ma et al. 2015). The social ecology, ethology and neurobiology of other species have been investigated since the acknowledgment of the apparent confinement of self-recognition to great apes and humans (Parker et al. 1994; Gallup 1997). Ethology Ecology & Evolution, 2016 Vol. 28, No. 2, 232–240, http://dx.doi.org/10.1080/03949370.2015.1102777

The role of Eurasian beaver (Castor fiber) in the storage, emission and deposition of carbon in lakes and rivers of the River Ob flood plain, western Siberia

Several studies have reported significant emission of greenhouse gasses (GHG) from beaver dams, suggesting that ponds created by beavers are a net source of CO2 and CH4. However, most evidence come from studies conducted in North America (on Castor canadensis) without a parallel comparison with the Eurasian beavers (Castor fiber) impacts and a critical consideration of the importance of the carbon deposition in dam sediments. The most abundant population of the Eurasian beaver lives in Russia, notably within the River Ob watershed in Western Siberia which is the second largest floodplain on Earth. Consequently, we assessed the holistic impact of Eurasian beavers on the multiple carbon pools in water and on other related biogeochemical parameters of the Obs floodplain streams. We compared dammed and flowing streams in a floodplain of the middle course of the river. We found that beavers in western Siberia increase the stream emission of methane by about 15 times by building their dams. This is similar to what has been documented in North America. A new finding from the present study is that Siberian beavers facilitate 1) nutrient recycling by speeding up the nutrient release from particulate organic matter; and 2) carbon sequestration by increasing the amount of dissolved organic carbon. This carbon becomes in part recalcitrant when buried in sediments and is, therefore, removed from the short-term carbon cycle. These new results should be taken into consideration in river management and provide a further reason for the conservation and management of Eurasian Beavers.

A new idea on the evolution of biodiversity

The understanding of the mechanisms that allow the origin of species has shed light on many processes such as speciation, adaptation and extinction, but how to explain the existence of such a huge diversity of species on Earth still remains a mystery. Many theories and evidence have corroborated the processes that allow species to evolve or become extinct. Currently there are different hypotheses but no clear demonstrations of the factors that maintain the species diversity of ecosystems. Those based on competitive principles have been criticized from both theoretical and empirical approaches. Only by studying biodiversity in the context of evolution, natural history and ecology (taking into consideration the avoidance of competition and dispersal abilities, the phenotypic plasticity, the heterogeneous landscape, the facilitation and the endogenosymbiosis) we can understand values and gaps of past theories trying to provide a broader understanding of life on Earth towards a Unified Theory of Biodiversity.The understanding of the mechanisms that allow the origin of species has shed light on many processes such as speciation, adaptation and extinction, but how to explain the existence of such a huge diversity of species on Earth still remains a mystery. Many theories and evidence have corroborated the processes that allow species to evolve or become extinct. Currently there are different hypotheses but no clear demonstrations of the factors that maintain the species diversity of ecosystems. Those based on competitive principles have been criticized from both theoretical and empirical approaches. Only by studying biodiversity in the context of evolution, natural history and ecology (taking into consideration the avoidance of competition and dispersal abilities, the phenotypic plasticity, the heterogeneous landscape, the facilitation and the endogenosymbiosis) we can understand values and gaps of past theories trying to provide a broader understanding of life on Earth towards a Unified Theory of Biodiversity.