Anthropogenic Land Use Change Research Articles

Anthropogenic land-use change decreases pollination and male and female fitness in terrestrial flowering plants

Abstract Background and Aims The majority of the earth's land area is currently occupied by humans. Measuring how terrestrial plants reproduce in these pervasive environments is essential for understanding their long-term viability and their ability to adapt to changing environments. Methods We conducted hierarchical and phylogenetically-independent meta-analyses to assess the overall effects of anthropogenic land-use changes on pollination, and male and female fitness in terrestrial plants. Key Results We found negative global effects of land use change (i.e., mainly habitat loss and fragmentation) on pollination and on female and male fitness of terrestrial flowering plants. Negative effects were stronger in plants with self-incompatibility (SI) systems and pollinated by invertebrates, regardless of life form and sexual expression. Pollination and female fitness of pollination generalist and specialist plants were similarly negatively affected by land-use change, whereas male fitness of specialist plants showed no effects. Conclusions Our findings indicate that angiosperm populations remaining in fragmented habitats negatively affect pollination, and female and male fitness, which will likely decrease the recruitment, survival, and long-term viability of plant populations remaining in fragmented landscapes. We underline the main current gaps of knowledge for future research agendas and call out not only for a decrease in the current rates of land-use changes across the world but also to embark on active restoration efforts to increase the area and connectivity of remaining natural habitats.

Seed‐dispersal mode and habitat connectivity underpin variation in carbon stocking between Brazilian biomes

Abstract In tropical forests, about 60%–80% of woody plant species depend on animal–plant interactions for dispersal. The dependence on animal species for dispersal makes this interaction very fragile in the face of anthropogenic changes in land use. Disrupting seed‐dispersal processes, principally zoochoric dispersal, could significantly alter the long‐term carbon storage potential of tropical forests. An important question is how landscape structure changes tree carbon stocks in different types of tropical vegetation and how variation is mediated by the dispersal mode of animal (zoochoric) or abiotic (non‐zoochoric) seeds. We focused on tree plots at 126 sites in Brazil spanning four types of forest and savanna vegetation, and calculated carbon stored in zoochoric, non‐zoochoric, and large frugivore‐dispersed species. Our results showed that carbon stocks in zoochoric species and non‐zoochoric species differ significantly among vegetation types, with rainforests having higher stocks in zoochoric species and deciduous seasonally dry tropical forests having higher values in non‐zoochoric species. A greater area of native vegetation promotes higher proportions of carbon stocks dispersed by large frugivore species, whereas a higher mean shape index reduces this proportion. Synthesis. This study highlights that seed‐dispersal type underpins the variation in carbon stocks between vegetation types and that the maintenance of habitat of large dispersers and connectivity are key for retaining carbon stocks in zoochoric species, particularly in rainforest and cerrado sensu stricto.

Microbiome diversity and zoonotic bacterial pathogen prevalence in Peromyscus mice from agricultural landscapes and synanthropic habitat.

Rodents are key reservoirs of zoonotic pathogens and play an important role in disease transmission to humans. Importantly, anthropogenic land-use change has been found to increase the abundance of rodents that thrive in human-built environments (synanthropic rodents), particularly rodent reservoirs of zoonotic disease. Anthropogenic environments also affect the microbiome of synanthropic wildlife, influencing wildlife health and potentially introducing novel pathogens. Our objective was to examine the effect of agricultural development and synanthropic habitat on microbiome diversity and the prevalence of zoonotic bacterial pathogens in wild Peromyscus mice to better understand the role of these rodents in pathogen maintenance and transmission. We conducted 16S amplicon sequencing on faecal samples using long-read nanopore sequencing technology to characterize the rodent microbiome. We compared microbiome diversity and composition between forest and synanthropic habitats in agricultural and undeveloped landscapes and screened for putative pathogenic bacteria. Microbiome richness, diversity, and evenness were higher in the agricultural landscape and synanthropic habitat compared to undeveloped-forest habitat. Microbiome composition also differed significantly between agricultural and undeveloped landscapes and forest and synanthropic habitats. We detected overall low diversity and abundance of putative pathogenic bacteria, though putative pathogens were more likely to be found in mice from the agricultural landscape. Our findings show that landscape- and habitat-level anthropogenic factors affect Peromyscus microbiomes and suggest that landscape-level agricultural development may be important to predict zoonotic pathogen prevalence. Ultimately, understanding how anthropogenic land-use change and synanthropy affect rodent microbiomes and pathogen prevalence is important to managing transmission of rodent-borne zoonotic diseases to humans.

Anthropogenic Changes in Land Use Impact the Emergence and Transmission of Infectious Diseases

Human interventions in natural landscapes have promoted rapid and profound transformations in the environment, generating great impacts at different levels, including on human and animal health. Actions such as deforestation for logging, intensive agriculture, construction of large hydroelectric dams, pastures for cattle, mining, and construction of roads that favor human access to remote areas have promoted habitat destruction, changes in trophic chains due to nutritional factors, loss of biodiversity, changes in the natural balance of vectors, mammals, hosts and pathogen reservoirs, and closer human contact with wildlife. Another important impact related to changes in land use is forest and habitat fragmentation. According to different investigations, anthropogenic actions causing changes in land use are potential inducers of emergence/reemergence and increased transmission of infectious diseases in the world, including those with pandemic potential. Most of these diseases are classified as zoonoses and many are arboviruses. Deforestation and agricultural intensification seem to be the events that most influence the incidence of zoonoses. Changes in land use may also favor a species jump to a zoonotic pathogen, making it a potential threat to humanity if it acquires an efficient capacity for inter-human transmission. Here, we summarize important evidence on how anthropogenic changes in land use influence the emergence and transmission of infectious diseases to humans.

An Overview of Anthropogenic Changes in Land Use and Land Cover, with Specific Attention to Climate Change and Unsustainable Agriculture

The worldwide need for food and the alterations in bioenergy demands associated with shifts in land use and land cover changes (LULCC) have given rise to environmental apprehensions, including global warming and climate change. There is substantial evidence indicating that we are currently witnessing human-induced transformations that could potentially result in a sixth mass extinction event. This study seeks to explore the connections between land use and land cover change (LULCC), forests, biodiversity, the carbon cycle, hydrology, climate, and various biogeochemical feedback mechanisms. These interrelationships play a crucial role in shaping future environmental outcomes and influencing climate change. Additionally, the review critically assesses existing research on the correlation between LULCC and climate, along with associated processes. The paper delves into ongoing investigations surrounding LULCC, its ecological repercussions, and its influence on the regulatory mechanisms of terrestrial ecosystems, ecosystem services, atmospheric chemistry, and the climate. It underscores the importance of developing land-use strategies rooted in a scientific evaluation of LULCC to promote sustainability and wider economic development, with a particular emphasis on addressing climate change. Global agreements and protocols also call for land use strategies that consider the implications of environmental degradation.

Anthropogenic changes in land use and their consequences on rodent populations reservoirs of zoonotic viruses

Anthropogenic changes in land use and their consequences on rodent populations reservoirs of zoonotic viruses

Financial influence on global risks of zoonotic emerging and re-emerging diseases: an integrative analysis

Emerging and re-emerging infectious diseases (EIDs), such as Ebola virus disease and highly pathogenic influenza, are serious threats to human health and wellbeing worldwide. The financial sector has an important, yet often ignored, influence as owners and investors in industries that are associated with anthropogenic land-use changes in ecosystems linked to increased EIDs risks. We aimed to analyse financial influence associated with EIDs risks that are affected by anthropogenic land-use changes. We also aimed to provide empirical assessments of such influence to help guide engagements by governments, private organisations, and non-governmental organisations with the financial sector to advance a planetary health agenda. For this integrative analysis, we identified regions in the world where there was evidence of a connection between EIDs and anthropogenic land-use changes between Nov 9, 1999, and Oct 25, 2021, through a targeted literature review of academic literature and grey literature to identify evidence of drivers of anthropogenic land-use change and their association with commodity production in these regions. We only included publications in English that showed a connection between deforestation and the production of one or more commodities. Publications merely describing spatial or temporal land-use change dynamics (eg, a reduction of forest or an increase of palm-oil plantations) were excluded. As we were assessing financial influence on corporate activities through ownership specifically, we focused our analysis on publicly listed companies. Equity data and data about ownership structure were extracted from Orbis, a company information database. We assessed financial influence by identifying financial entities with the largest equity ownership, descriptively mapping transboundary connections between investors and publicly listed companies. 227 public and private companies operating in five economic sectors (ie, production of palm oil, pulp and wood products, cocoa, soybeans, and beef) between Dec 15, 2020, and March 8, 2021, were identified. Of these 227, 99 (44%) were publicly listed companies, with 2310 unique shareholders. These publicly listed companies operated in six geographical regions, resulting in nine case-study regions. 54 (55%) companies with complete geographical information were included in the countries network. Four financial entities (ie, Dimensional, Vanguard, BlackRock, and Norway's sovereign wealth fund) each had ownership in 39 companies or more in three of the case-study regions (ie, north America, east Asia, and Europe). Four large US-based asset managers (ie, Vanguard, BlackRock, T Rowe Price, and State Street) were the largest owners of publicly listed companies in terms of total equity size, with ownership amounts for these four entities ranging from US$8 billion to $21 billion. The specific patterns of cross-national ownership depended on the region of interest; for example, financial influence on EIDs risks that was associated with commodity production in southeast and east Asia came from not only global asset managers but also Malaysian, Chinese, Japanese, and Korean financial entities. India, Brazil, the USA, Mexico, and Argentina were the countries towards which investments were most directed. Although commodity supply chains and financial markets are highly globalised, a small number of investors and countries could be viewed as disproportionally influential in sectors that increase EIDs risks. Such financial influence could be used to develop and implement effective policies to reduce ecological degradation and mitigate EIDs risks and their effects on population health. Formas and Networks of Financial Rupture-how cascading changes in the climate and ecosystems could impact on the financial sector.

Cattle Farming and Plantation Forest are Associated with Bartonella Occurrence in Wild Rodents.

Bartonella spp. are intracellular hemotropic bacteria primarily transmitted by arthropod vectors to various mammalian hosts, including humans. In this study, we conducted a survey on wild populations of sigmodontine rodents, Akodon azarae and Oxymycterus rufus, inhabiting the Paraná River delta region. The study involved eight grids organized in a crossed 2 × 2 design, where four of the grids were exposed to cattle while the other four were not, and four grids were located in implanted forest while the remaining four were in natural grasslands. Our objective was to examine whether the occurrence of Bartonella spp. in rodents was associated with silvopastoral activities (cattle raising associated with timber production) conducted in the region. Additionally, we evaluated the associations between Bartonella infection and other environmental and host factors. We present compelling evidence of a significant positive association between Bartonella prevalence and the presence of implanted forests and cattle. Furthermore, we identified the presence of a Bartonella genotype related to the pathogen Bartonella rochalimaea, infecting both A. azarae and Ox. rufus. These findings suggest that anthropogenic land-use changes, particularly the development of silvopastoral practices in the region, may disrupt the dynamics of Bartonella.

Integrated global assessment of the natural forest carbon potential

Forests are a substantial terrestrial carbon sink, but anthropogenic changes in land use and climate have considerably reduced the scale of this system1. Remote-sensing estimates to quantify carbon losses from global forests2–5 are characterized by considerable uncertainty and we lack a comprehensive ground-sourced evaluation to benchmark these estimates. Here we combine several ground-sourced6 and satellite-derived approaches2,7,8 to evaluate the scale of the global forest carbon potential outside agricultural and urban lands. Despite regional variation, the predictions demonstrated remarkable consistency at a global scale, with only a 12% difference between the ground-sourced and satellite-derived estimates. At present, global forest carbon storage is markedly under the natural potential, with a total deficit of 226 Gt (model range = 151–363 Gt) in areas with low human footprint. Most (61%, 139 Gt C) of this potential is in areas with existing forests, in which ecosystem protection can allow forests to recover to maturity. The remaining 39% (87 Gt C) of potential lies in regions in which forests have been removed or fragmented. Although forests cannot be a substitute for emissions reductions, our results support the idea2,3,9 that the conservation, restoration and sustainable management of diverse forests offer valuable contributions to meeting global climate and biodiversity targets.

Multi-scale habitat selection throughout the annual cycle of a long-distance avian migrant

Long-distance migrants are constrained by widely separated hospitable habitats in geographically isolated locations, making them vulnerable to environmental change, both through natural and anthropogenic causes. Knowledge about their resource selection decisions is imperative to understand the drivers of their declines. The distinct periods within an annual cycle, when individuals experience different environmental circumstances, are inextricably linked through carry-over effects which can have important consequences for the individual, and consequently the population. In this study, we employ precise archival GPS-tracking data of European Nightjars (Caprimulgus europaeus) and high-resolution global land cover data to examine habitat selection during the sedentary wintering and breeding periods, as well as during autumn and spring migration, using a correlational approach. We demonstrate how nightjars use general habitat characteristics, such as landscape diversity, for high-order habitat selection, while resource selection at a finer spatial scale is reliant on fine-scale variables related to a habitat’s suitability, such as surface area of grassland and shrubland. We show that nightjars favour spatially diverse landscapes, which allows them to minimize time spent searching for optimal habitats. The considerable variation in the drivers of habitat selection between and within seasons shows how anthropogenic land-use change can have an array of different impacts on migrants by influencing large- and fine-scale habitat selection. This study shows the advantages of an individual based GPS-tracking approach, combined with high spatial resolution remote sensing data, and highlights the need for full annual-cycle research on scale dependent habitat selection of long-distance avian migrants.

Gut microbial shifts in vampire bats linked to immunity due to changed diet in human disturbed landscapes

Anthropogenic land-use change alters wildlife habitats and modifies species composition, diversity, and contacts among wildlife, livestock, and humans. Such human-modified ecosystems have been associated with emerging infectious diseases, threatening human and animal health. However, human disturbance also creates new resources that some species can exploit. Common vampire bats (Desmodus rotundus) in Latin America constitute an important example, as their adaptation to human-modified habitats and livestock blood-feeding has implications for e.g., rabies transmission. Despite the well-known links between habitat degradation and disease emergence, few studies have explored how human-induced disturbance influences wildlife behavioural ecology and health, which can alter disease dynamics. To evaluate links among habitat disturbance, diet shifts, gut microbiota, and immunity, we quantified disturbance around roosting caves of common vampire bats in Costa Rica, measured their long-term diet preferences (livestock or wildlife blood) using stable isotopes of carbon and nitrogen, evaluated innate and adaptive immune markers, and characterized their gut microbiota. We observed that bats from roosting caves with more cattle farming nearby fed more on cattle blood. Moreover, gut microbial richness and the abundance of specific gut microbes differed according to feeding preferences. Interestingly, bats feeding primarily on wildlife blood harboured a higher abundance of the bacteria Edwardsiella sp., which tended to be associated with higher immunoglobulin G levels. Our results highlight how human land-use change may indirectly affect wildlife health and emerging infectious diseases through diet-induced shifts in microbiota, with implications for host immunity and potential consequences for susceptibility to pathogens.

Extinction risks and mitigation for a megaherbivore, the giraffe, in a human-influenced landscape under climate change.

Megaherbivores play "outsized" roles in ecosystem functioning but are vulnerable to human impacts such as overhunting, land-use changes, and climate extremes. However, such impacts-and combinations of these impacts-on population dynamics are rarely examined using empirical data. To guide effective conservation actions under increasing global-change pressures, we developed a socially structured individual-based model (IBM) using long-term demographic data from female giraffes (Giraffa camelopardalis) in a human-influenced landscape in northern Tanzania, the Tarangire Ecosystem. This unfenced system includes savanna habitats with a wide gradient of anthropogenic pressures, from national parks, a wildlife ranch and community conservation areas, to unprotected village lands. We then simulated and projected over 50 years how realistic environmental and land-use management changes might affect this metapopulation of female giraffes. Scenarios included: (1) anthropogenic land-use changes including roads and agricultural/urban expansion; (2) reduction or improvement in wildlife law enforcement measures; (3) changes in populations of natural predators and migratory alternative prey; and (4) increases in rainfall as predicted for East Africa. The factor causing the greatest risk of rapid declines in female giraffe abundance in our simulations was a reduction in law enforcement leading to more poaching. Other threats decreased abundances of giraffes, but improving law enforcement in both of the study area's protected areas mitigated these impacts: a 0.01 increase in giraffe survival probability from improved law enforcement mitigated a 25% rise in heavy rainfall events by increasing abundance 19%, and mitigated the expansion of towns and blockage of dispersal movements by increasing abundance 22%. Our IBM enabled us to further quantify fine-scale abundance changes among female giraffe social communities, revealing potential source-sink interactions within the metapopulation. This flexible methodology can be adapted to test additional ecological questions in this landscape, or to model populations of giraffes or other species in different ecosystems.

Differing taxonomic responses of mosquito vectors to anthropogenic land-use change in Latin America and the Caribbean.

Anthropogenic land-use change, such as deforestation and urban development, can affect the emergence and re-emergence of mosquito-borne diseases, e.g., dengue and malaria, by creating more favourable vector habitats. There has been a limited assessment of how mosquito vectors respond to land-use changes, including differential species responses, and the dynamic nature of these responses. Improved understanding could help design effective disease control strategies. We compiled an extensive dataset of 10,244 Aedes and Anopheles mosquito abundance records across multiple land-use types at 632 sites in Latin America and the Caribbean. Using a Bayesian mixed effects modelling framework to account for between-study differences, we compared spatial differences in the abundance and species richness of mosquitoes across multiple land-use types, including agricultural and urban areas. Overall, we found that mosquito responses to anthropogenic land-use change were highly inconsistent, with pronounced responses observed at the genus- and species levels. There were strong declines in Aedes (-26%) and Anopheles (-35%) species richness in urban areas, however certain species such as Aedes aegypti, thrived in response to anthropogenic disturbance. When abundance records were coupled with remotely sensed forest loss data, we detected a strong positive response of dominant and secondary malaria vectors to recent deforestation. This highlights the importance of the temporal dynamics of land-use change in driving disease risk and the value of large synthetic datasets for understanding changing disease risk with environmental change.

Combining isothermal recombinase polymerase amplification with lateral flow assay for diagnosis of P. cynomolgi malaria infection.

Plasmodium cynomolgi is a nonhuman primate parasite that causes malaria in humans and is transmitted by the Anopheles mosquito. Macaques, the natural hosts of P. cynomolgi, are widely distributed in Asia, especially in Southeast Asia. Anthropogenic land-use changes and wildlife habitat reduction due to local environmental changes, deforestation, urban expansion, and construction increased the frequency of human-macaque-vector interactions and facilitated the emergence of zoonotic malaria, causing an exponential increase in the infection rates in this area. Although microscopic tools are the gold standard for malaria diagnosis, they have very low sensitivity. Therefore, disease control and prevention require rapid, sensitive and accurate diagnostic tests. This study aims to develop a diagnostic method using a recombinase polymerase amplification (RPA) combined with a lateral flow (LF) strip method to specifically diagnose P. cynomolgi. Laboratory validation determined the method's sensitivity and specificity compared to the nested PCR method. The lower limit of detection was 22.14 copies/μl of recombinant plasmid per reaction. The combination method represented 81.82% sensitivity and 94.74% specificity compared to the nested PCR. The diagnostic testing developed in this study combines a recombinase polymerase amplification (RPA) and a lateral flow (LF) strip, offering rapid high sensitivity and specificity. Further development of this technique could make it a promising method for detecting P. cynomolgi.

Assessment of differences in peat physico-chemical properties, surface subsidence and GHG emissions between the major land-uses of Selangor peatlands

Tropical peatlands are globally important ecosystems for carbon storage, biodiversity conservation, water storage and regulation, and several other valuable ecosystem services. Despite their importance, peatlands in Southeast Asia have been heavily degraded by anthropogenic disturbances such as drainage, agricultural conversion, and fire. In this spatially extensive study we characterised peat properties, nutrient concentrations, surface subsidence rates and greenhouse gas emissions from peatlands of Selangor, Peninsular Malaysia under different land-uses: Secondary Forest, Fire affected and replanted forest (Burnt), Pineapple Plantation, Mixed Agriculture, Smallholder Oil Palm Monoculture, and Industrial Oil Palm Monoculture. All the measured peat physico-chemical properties and nutrient concentrations were significantly different between land-uses. Principal component analyses indicated that peat under the Mixed Agriculture and Burnt land-uses showed the greatest degree of modification relative to peat under the Secondary Forest land-use. Burnt land-use also showed a significantly higher subsidence rate (4.4 ± 1.2 cm yr−1) than all the other land-uses (ranging between 1.8 ± 0.47 and 3.2 ± 0.5 cm yr−1). Water table was significantly higher at the Burnt land-use (-26 cm) than all other land-uses, likely reflecting fire-prevention drain blocking measures as well as lower land surface heights post fire. Smallholder oil palm land-use had the lowest water table (−68 cm), while water table level in all other land-uses did not significantly differ from that of Secondary Forest (−43 cm). Peat surface level changes were positively related to increase in drainage, showing the importance of maintaining a high water table level in reducing peat degradation and carbon loss from peatlands. Total CO2 (mean range 492 to 1019 mg m−2 hr-1) and CH4 emissions (mean range 637 to 1422 µg m−2 hr-1) did not significantly differ between land-uses or seasons. CH4 emissions were negligible under all land-uses and higher emissions were correlated with a higher water table level. Taken together, the results show that anthropogenic land-use change impacts the physico-chemical properties and nutrient content of peat, and that increased drainage alongside changes in other peat properties leads to increased peat subsidence and carbon loss.

Soils at the temperate forest edge: An investigation of soil characteristics and carbon dynamics

Global proliferation of forest edges through anthropogenic land-use change and forest fragmentation is well documented, and while forest fragmentation has clear consequences for soil carbon (C) cycling, underlying drivers of belowground activity at the forest edge remain poorly understood. Increasing soil C losses via respiration have been observed at rural forest edges, but this process was suppressed at urban forest edges. We offer a comprehensive, coupled investigation of abiotic soil conditions and biotic soil activity from forest edge to interior at eight sites along an urbanization gradient to elucidate how environmental stressors are linked to soil C cycling at the forest edge. Despite significant diverging trends in edge soil C losses between urban and rural sites, we did not find comparable differences in soil % C or microbial enzyme activity, suggesting an unexpected decoupling of soil C fluxes and pools at forest edges. We demonstrate that across site types, soils at forest edges were less acidic than the forest interior (p < 0.0001), and soil pH was positively correlated with soil calcium, magnesium and sodium content (adj R2 = 0.37), which were also elevated at the edge. Compared to forest interior, forest edge soils exhibited a 17.8 % increase in sand content and elevated freeze-thaw frequency with probable downstream effects on root turnover and decomposition. Using these and other novel forest edge data, we demonstrate that significant variation in edge soil respiration (adj R2 = 0.46; p = 0.0002) and C content (adj R2 = 0.86; p < 0.0001) can be explained using soil parameters often mediated by human activity (e.g., soil pH, trace metal and cation concentrations, soil temperature), and we emphasize the complex influence of multiple, simultaneous global change drivers at forest edges. Forest edge soils reflect legacies of anthropogenic land-use and modern human management, and this must be accounted for to understand soil activity and C cycling across fragmented landscapes.

Living in a changing world: effects of roads and Pinus monocultures on an anuran metacommunity in southern Brazil

The loss of species with unique traits and evolutionary histories resulting from anthropogenic land-use changes poses a risk to the maintenance of ecosystems. We investigated the influence of Pinus monocultures and roads on functional, phylogenetic, and taxonomic composition, as well as on functional dispersion of an anuran metacommunity in Brazil. We expected the influence of anthropogenic stressors to (1) vary according to the diversity component, with greater influence on the functional and phylogenetic components than on the taxonomic component; and (2) traits related to habitat exploration to be more influenced by monocultures, while the traits related to dispersal and physiological control to be influenced by roads and monocultures, especially for species with smaller body size and low dispersal potential. We found that, while the distance from ponds to monocultures influences the phylogenetic composition, distance to roads influences functional composition and dispersion. The anthropogenic stressors affect the structure of these communities, even those formed by generalist species in terms of habitat use. The phylogenetic composition shows that the distribution of evolutionary clades in human-modified areas is linked to the preferred habitat of species, while functional composition is related to body size. Furthermore, functional dispersion was higher in areas closer to roads, contrary to our expectations. Our results represent new evidence for the conservation of anurans in modified landscapes reinforcing the importance of including functional and phylogenetic information in conservation-driven studies.

Diversity and distribution patterns of Ecuador’s dung beetles (Coleoptera: Scarabaeinae)

IntroductionEcuador harbors an astounding number of ecosystems and species. However, anthropogenic land-use changes are the primary drivers of biodiversity loss in major taxonomic groups, especially insects. Among them, the Scarabaeinae subfamily containing dung beetles, is an excellent taxon for studying taxonomic and functional diversity, as they are relatively stable taxonomically and have a wide variety of ecological services. Their distribution is mainly influenced by biogeography and climate as their main ecological and environmental factors will allow us to quantify what aspects of diversity are being impacted under different circumstances and at different scales.MethodsTo understand the main of dung beetle distribution drivers, we analyzed a museum database from the National Institute of Biodiversity, Ecuador (INABIO) of over 5000 dung beetle specimens with 122 species collected throughout the country, we addressed the following questions: i) How does tribe distribution vary across climatic and elevational gradients? and ii) How does functional and taxonomic beta diversity vary across spatial scales? To address them, we focused on three main tribes: Canthonini, Coprini, and Phanaeini. We constructed GLM’s and niche-based models to estimate Ecuador’s distributions based on climate variables to explore potential predictor variables, using tree classification models, along with taxonomic and functional beta diversity across scales.ResultsThe main variables influencing dung beetle distribution were elevation, and precipitation. The Phanaeini niche model is significantly better at predicting dung beetle presence throughout Ecuador than Canthonini and Coprini. We found high turnover in functional groups at larger scales, suggesting that dung beetles show high levels of habitat specialization, which associates to our findings where taxonomic beta diversity was higher in the Amazon basin compared to the coastal region. This may be due to the higher rate of dung production in Amazonia. Our findings also suggest that dung beetles are not found in areas above 2000m, mainly because dung beetles are well adapted to warmer and moist climatic regions. Precipitation and elevation are consistently essential variables for predicting Canthonini and Coprini presence, while temperature explains Phanaeini presence. Low levels of species turnover at the regional scale may be because the total species richness in Ecuador is different, where divergence in taxonomic beta diversity between the two regions is an artifact of such differences in richness in Amazonia versus the coast, the distinction is also due to nonrandomly low taxonomic beta diversity levels in the coastal region.ConclusionsOur results provide an essential framework for evaluating potential dung beetle habitat and diversity at different scales; therefore, by identifying dung beetles’ diversity, combined with considerations of habitat fragmentation, human land-use alteration, and climate change, will be an important next step to inform better and prioritize dung beetle conservation efforts in other countries.

Wildlife in climate refugia: Mammalian diversity, occupancy, and tiger distribution in the Western Himalayas, Nepal

Anthropogenic land-use change continues to be predicated as a major driver of terrestrial biodiversity loss for the rest of this century. It has been determined that the effect of climate change on wildlife population will accelerate the rate and process of decline of global vertebrate populations. We investigated wildlife composition, occupancy, and activity pattern along the larger climate resilient forests that serve as microrefugia for a wide range of species under the escalating climate change. We used camera trap survey covering 250 km2 of climate microrefugia in Dadeldhura hills in far western region of Nepal. We used 62 trapping locations accumulating 1800 trap nights taking 98,916 photographs in 62 days-survey period during the summer season of 2020. We photographed 23 mammalian species with estimated species richness of 30 species (95% CI: 25-34) based on multi-species occupancy model. We estimated overall species occupancy ψ(SE(ψ)) to be 0.87 (0.09) in climatic microrefugia. While human activity predominated throughout the day, the majority of animals was found to exhibit nocturnal temporal patterns. Tiger and hyaena, two of the top predators, were newly discovered in the western Himalayan range of Nepal, with their discovery at the 34 highest elevations of 2511 meters and 2000m, respectively. In Nepal, high-altitude tiger range is characterized by tiger distribution above a 2000 m cutoff representing habitats in the physiographic zone of high mountains and above. Our findings establish a baseline and show that the climatic microrefugia that have been identified have high levels of species richness and occupancy, which characterize the Dadeldhura hill forest ranges as biologically varied and ecologically significant habitat. These areas identified as climatic microrefugia habitats should be the focus of conservation efforts, particularly efforts to reduce human disturbance and adapt to climate change.

Changing distributions of the cosmopolitan mosquito species Culex quinquefasciatus Say and endemic Cx. pervigilans Bergroth (Diptera: Culicidae) in New Zealand

ABSTRACT New Zealand has 13 endemic mosquito species, which are predominantly bird-biters, exhibiting low levels of vector competence, and are adapted to their native ecosystems. Anthropogenic land-use change are well-suited to domesticated exotic species that have already established here. While some endemic species, such as Culex pervigilans, can also be found vutilising such environments, there are indications of population decline and displacement. The cosmopolitan Cx. quinquefasciatus has been established in New Zealand for more than 180 years, and was believed to be confined to the warmer, northern regions. However, biosecurity records of obtained specimens collected by the National Mosquito Surveillance Program, at various points of entry (POE) for goods and international travel, suggest an expansion of this range. Changes in the distributions of Cx. quinquefasciatus and Cx. pervigilans over the last fifteen years in New Zealand, are evaluated herein, with the conclusion that Cx. quinquefasciatus is increasing both in distribution and population density over time, and should be considered an invasive species. Evidence of a southward spread is likely a result of anthropogenic environmental changes particularly favourable to Cx. quinquefasciatus. A trend of considerable ecological and public health importance. Similarly clear effects on urban Cx. pervigilans populations were not observed.