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1.
J Anat ; 244(6): 959-976, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38284134

RESUMO

Phytosaurs are a group of Upper Triassic semi-aquatic archosauriform reptiles. Their variable skull morphology forms the foundation of our understanding of their relationships and paleoecology, while only a few studies have focused on demonstrating the existence of postcranial variation. The numbers of vertebrae in the sacrum are thought to vary from two, the plesiomorphic condition for archosauriforms, to three, with the addition of a sacralized dorsal (i.e., dorsosacral) vertebra. In this study, we demonstrate the presence of a sacralized first caudal (i.e., caudosacral) vertebra in a sacrum belonging to Machaeroprosopus mccauleyi. We rule out taphonomic distortion or pathology as explanations for the inclusion of this element in the sacrum, suggesting instead that it occurred through modifications of the same developmental processes that likely produced dorsosacral vertebrae in phytosaurs. Additionally, we show that a dorsosacral vertebra is common in phytosaur specimens from the Chinle Formation and Dockum Group of the southwestern United States and suggest that it may be widespread among phytosaurs. The addition of sacral vertebrae potentially aided adaptation to larger body sizes or more terrestrial lifestyles in certain taxa.


Assuntos
Fósseis , Sacro , Animais , Sacro/anatomia & histologia , Dinossauros/anatomia & histologia , Evolução Biológica , Répteis/anatomia & histologia , Crânio/anatomia & histologia , Filogenia
2.
Glob Chang Biol ; 30(8): e17468, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39161313

RESUMO

Climate change has profound impacts on forest ecosystem dynamics and could lead to the emergence of novel ecosystems via changes in species composition, forest structure, and potentially a complete loss of tree cover. Disturbances fundamentally shape those dynamics: the prevailing disturbance regime of a region determines the inherent variability of a system, and its climate-mediated change could accelerate forest transformation. We used the individual-based forest landscape and disturbance model iLand to investigate the resilience of three protected temperate forest landscapes on three continents-selected to represent a gradient from low to high disturbance activity-to changing climate and disturbance regimes. In scenarios of sustained strong global warming, natural disturbances increased across all landscapes regardless of projected changes in precipitation (up to a sevenfold increase in disturbance rate over the 180-year simulation period). Forests in landscapes with historically high disturbance activity had a higher chance of remaining resilient in the future, retaining their structure and composition within the range of variability inherent to the system. However, the risk of regime shift and forest loss was also highest in these systems, suggesting forests may be vulnerable to abrupt change beyond a threshold of increasing disturbance activity. Resilience generally decreased with increasing severity of climate change. Novelty in tree species composition was more common than novelty in forest structure, especially under dry climate scenarios. Forests close to the upper tree line experienced high novelty in structure across all three study systems. Our results highlight common patterns and processes of forest change, while also underlining the diverse and context-specific responses of temperate forest landscapes to climate change. Understanding past and future disturbance regimes can anticipate the magnitude and direction of forest change. Yet, even across a broad gradient of disturbance activity, we conclude that climate change mitigation is the most effective means of maintaining forest resilience.


Assuntos
Mudança Climática , Florestas , Árvores , Modelos Teóricos , Conservação dos Recursos Naturais
3.
J Hum Evol ; 195: 103582, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39213793

RESUMO

The earliest evidence for complex tool use in the archaeological record dates to 3.3 Ma. While wooden tools may have been used by our earliest ancestors, the evidence is absent due to poor preservation. However, insights into possible early hominin wooden tool use can be gained from observing the tool-use practices of our closest living relatives, chimpanzees (Pan troglodytes). By using stone hammers used to crack various nuts, chimpanzees leave a durable material signature comprised of formal tools and associated diagnostic fragments. While the archaeological evidence of chimpanzee wooden tool use is temporary, the combination of stone hammers and wooden anvils can create a more enduring lithic record. This study explores the lithic assemblages associated with wooden and stone anvil use at nut-cracking sites in Taï National Park, Côte d'Ivoire, using technological and use-wear analyses. Our results indicate clear differences in density, fracture patterns, and use-wear in the lithic records between wooden anvil and stone anvil sites. New archaeological excavations at six chimpanzee nut-cracking sites reveal that the anvils' material directly influences the visibility of nut-cracking evidence in the archaeological record. By examining the nature of the lithic signatures associated with wooden anvil and stone anvil use by chimpanzees, we can formulate hypotheses about the probability of such behaviors being preserved and identifiable in the Plio-Pleistocene hominin archaeological record. The variability in material signatures from nut-cracking on different anvils suggests that stone anvils leave a clear archaeological record. Evidence for wooden anvil use is likely underrepresented due to the more ephemeral nature of the associated percussive damage and material signature. It may, however, still be possible, albeit challenging, to identify wooden anvil use in the archaeological record.


Assuntos
Arqueologia , Nozes , Pan troglodytes , Comportamento de Utilização de Ferramentas , Animais , Côte d'Ivoire , Madeira
4.
Conserv Biol ; 38(2): e14215, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37990845

RESUMO

China announced the development of its first 5 national parks in 2021, the primary objective of which is to conserve the natural state and integrity of natural ecosystems. As such, ecosystem services and biodiversity levels are crucial assessment factors for the parks. For Giant Panda National Park (GPNP), we evaluated ecological sensitivity based on water and soil erosion and rocky desertification; ecosystem services based on headwater conservation, soil and water conservation, and biodiversity conservation; and presence of giant panda (Ailuropoda melanoleuca) and sympatric species (e.g., takin [Budorcas taxicolor], Asiatic black bear [Ursus thibetanus]) habitat suitability derived from niche modeling to identify the ecosystem status and assess ecological problems within the park. From our results, we proposed ecologically critical areas to target to meet the park's goals. The suitable habitat for pandas and sympatric species encompassed 62.98% of the park and occurred mainly in the Minshan Mountains. One quarter of the total area (25.67%) contained areas important for ecosystem services. Ecologically sensitive and extremely sensitive areas covered 88.78% of the park and were distributed mainly in Qionglaishan and Minshan Mountains. This coverage indicated that there was much habitat for pandas and sympatric species but that the ecosystems in GPNP are vulnerable. Therefore, ecologically critical areas encompassed all suitable habitats for all the species examined and areas important and extremely important to ecosystem service provision,ecologically sensitive and extremely sensitive areas, encompassed 15.17% of panda habitat, accounted for 16.37% of the GPNP area, and were distributed mainly in the Minshan Mountains. Our results indicated where conservation efforts should be focused in the park and that by identifying ecologically critical areas managers can provide targeted protection for wildlife habitat and ecosystems and effectively and efficiently protect the composite ecosystem. Additionally, our methods can be used to inform development of new national parks.


Medición de los servicios ambientales y la sensibilidad ecológica para una conservación integral en el Parque Nacional del Panda Gigante Resumen China anunció el crecimiento de sus primeros cinco parques nacionales en 2021, con el objetivo principal de conservar el estado natural y la integridad de los ecosistemas naturales. Para ello, los servicios ambientales y los niveles de biodiversidad son factores cruciales de evaluación para los parques. Para poder identificar el estado del ecosistema y evaluar los problemas ecológicos dentro del Parque Nacional del Panda Gigante (PNPG), analizamos la sensibilidad ecológica con base en la erosión del agua y del suelo y la desertificación rocosa; los servicios ambientales con base en el suministro de conservación del agua, del agua y del suelo y de la biodiversidad; y la idoneidad de hábitat del panda gigante (Ailuropoda melanoleuca) y de especies simpátricas (takín [Budorcas taxicolor], oso negro asiático [Ursus thibetanus]) derivada del modelo de nichos. A partir de nuestros resultados proponemos enfocarnos en áreas ecológicamente críticas para lograr los objetivos del parque. El hábitat idóneo para los pandas y las especies simpátricas englobó el 62.98% del parque y se ubicó principalmente en las montañas Minshan. Un cuarto del área total (25.67%) albergó áreas importantes para los servicios ambientales. Las áreas ecológicamente sensibles y extremadamente sensibles cubrieron el 88.78% del parque y se distribuyeron en las montañas Minshan y Qionglaishan. Esta cobertura indica que hay bastante hábitat para los pandas y las especies simpátricas pero que los ecosistemas en el PNPG son vulnerables. Por lo tanto, las áreas ecológicamente críticas englobaron todos los hábitats para todas las especies analizadas y todas las áreas importantes y extremadamente importantes para el suministro de servicios ambientales. Las áreas ecológicamente sensibles y extremadamente sensibles englobaron el 15.17% del hábitat del panda, representaron el 16.37% del área del PNPG y se localizaron principalmente en las montañas Minshan. Nuestros resultados indican en dónde se deben enfocar los esfuerzos de conservación dentro del parque y que, si identificamos las áreas ecológicamente críticas, los gestores pueden proporcionar una protección focalizada para el hábitat y los ecosistemas y así proteger efectiva y eficientemente el ecosistema compuesto. Además, nuestro método puede usarse para guiar el desarrollo de nuevos parques nacionales.


大熊猫国家公园能实现物种和生态完整性的多重保护 中国在2021年宣布设立首批5个国家公园, 保护自然生态系统的真实性和完整性是其优先目标, 而生态系统服务和生物多样性水平是关键的评估要素。大熊猫国家公园作为首批唯一以单一物种命名的国家公园, 通过评估其生态系统服务、生态敏感性, 同时结合大熊猫及同域分布物种(羚牛、亚洲黑熊)的栖息地适宜性, 以揭示其国家公园内生态系统的状态及其面临的问题, 明确其生态关键区以实现多重保护的目标。我们发现大熊猫国家公园包含了超过62.98%的大熊猫和同域物种的适宜栖息地, 主要分布在岷山山系;其次, 大熊猫国家公园包含了25.67%的生态系统服务重要区域和高达88.78%的生态敏感区域, 主要分布在岷山山系和邛崃山山系。这表明尽管大熊猫国家公园内包含了大熊猫及同域物种所需的大面积适宜栖息地, 但是其生态系统具有较强的脆弱性。若将同时包含大熊猫及同域物种的适宜栖息地、生态系统服务重要和极重要区、生态敏感和极敏感的区域定义为生态关键区, 其面积占比为16.37%, 覆盖了15.17%的大熊猫栖息地, 主要分布在岷山山系。因此, 基于生态关键区制定新的科学的、针对性的保护措施, 不仅可以更好的来保护野生动物栖息地和应对生态系统的威胁, 而且也有效且高效地保护多重生态系统。.


Assuntos
Ecossistema , Ursidae , Animais , Parques Recreativos , Conservação dos Recursos Naturais/métodos , Biodiversidade , China
5.
Oecologia ; 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39251421

RESUMO

Resource availability and habitat heterogeneity are essential drivers of biodiversity, but their individual roles often remain unclear since both factors are often correlated. Here, we tested the more-individuals hypothesis (MIH) and the habitat-heterogeneity hypothesis (HHH) for bacteria, fungi, dipterans, coleopterans, birds, and mammals on 100 experimentally exposed carcasses ranging by three orders of magnitude in body mass. At the level of each carcass we found marginal or significant support for the MIH for bacteria, fungi, and beetles in spring and significant support for fungi, dipterans, and mammals in summer. The HHH was supported only for bacteria in spring, while it was supported for all groups except mammals in summer. Overall multidiversity always increased with body mass, with a steeper increase in summer. Abundance based rarefaction-extrapolation curves for three classes of body mass showed the highest species richness for medium-sized carcasses, particular for dipterans and microbes, supporting the HHH also among carcasses. These findings complement existing necromass studies of deadwood, showing there are more niches associated with larger resource amounts and an increasing habitat heterogeneity between carcasses most pronounced for medium-sized species. Higher resource amount led to increased diversity of carrion-consuming organisms in summer, particularly due to the increasing number of niches with increasing size. Our findings underline the importance of distributed large carrion as well as medium-sized carrion in ecosystems supporting overall biodiversity of carrion-consumers. Furthermore, the different responses in spring and summer may inform strategies of carrion enrichment management schemes throughout the year.

6.
J Environ Manage ; 355: 120532, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38460327

RESUMO

In Nigeria and tropical Africa, the bias towards the protection of natural sites on account of terrestrial biodiversity or their resultant ecosystem services has led to a considerably low number of freshwater conservation studies in the region. To close this gap, six lotic freshwater systems in three different natural sites (Obudu Mountains, Agbokim Waterfalls, and Cross River National Park) along the Cameroon border of Nigeria were evaluated for the biodiversity of macroinvertebrates and some aspects of water quality in December 2021 and March 2022. Among other macroinvertebrate-related indices, the community conservation index (CCI), which considers the presence of threatened, rare, and notable species, was used for the conservation evaluation of the freshwater systems. The Ephemeroptera-Plecoptera-Trichoptera (EPT) species were notably rich at the sites, with over 12 species each at the Afundu Stream, Kwa River, Cataract Stream, and Agbokim River. All of the sites had a very high conservation value, according to the CCI, which was greater than 20. Some Obudu sites (Grotto and Becheve streams), despite having fewer EPT taxa, had higher CCI than the Kwa or Agbokim River. This was due to the presence of the endangered damselflies (Africocypha centripunctata and Allocnemis vicki) at the Obudu sites and a rare mayfly species in Nigeria (Tricorythus tinctus), which was reported at Agbokim and Kwa Rivers. The presence of a notable damselfly genus (Pentaphlebia) at the Afundu stream of the Obudu Mountains also raises some hope that the critically endangered damselfly (Pentaphlebia gamblesi), whose adult was last seen in 1973, could still be alive at the site. Canonical Correspondence Analysis revealed that the proportion of scrapers had a strong association with high BOD and EC in Agbokim River, while the Becheve and Grotto streams which had high vegetal cover was positively associated with shredders. Also, increasing DO in Afundu Stream, Kwa River and Cataract Stream was positively associated with EPT richness. This study revealed that more freshwater ecological studies need to be conducted at isolated natural sites and protected areas in Africa. Findings from such studies have implications for preserving freshwater ecosystems of high conservation value from the various threats that characterize the Anthropocene.


Assuntos
Catarata , Ephemeroptera , Animais , Ecossistema , Nigéria , Camarões , Guiné , Biodiversidade , Água Doce , Florestas , Insetos , Invertebrados , Monitoramento Ambiental
7.
J Environ Manage ; 362: 121335, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38833934

RESUMO

Transitional features of desert environments partially determine the risks associated with ecosystems. Influenced by climate change and human activities, the variability and uncertainty of desertification levels and ecological risks in the Qinghai Area of Qilian Mountain National Park (QMNPQA) has become increasingly prominent. As a critical ecological barrier in northwest China, monitoring desertification dynamics and ecological risks is crucial for maintaining ecosystem stability. This study identifies the optimal monitoring model from four constructed desertification monitoring models and analyzes spatiotemporal changes in desertification. The spatial and temporal changes in ecological risks and their primary driving factors were analyzed using methods such as raster overlay calculation, geographic detector, cloud model, and trend analysis. The main conclusions are as follows: The desertification feature spatial model based on GNDVI-Albedo demonstrates better applicability in the study area, with an inversion accuracy of 81.24%. The levels of desertification and ecological risks in QMNPQA exhibit significant spatial heterogeneity, with a gradual decrease observed from northwest to southeast. From 2000 to 2020, there is an overall decreasing trend in desertification levels and ecological risks, with the decreasing trend area accounting for 89.82% and 85.71% respectively, mainly concentrated in the southeastern and northwestern parts of the study area. The proportion of areas with increasing trends is 4.49% and 7.05% respectively, scattered in patches in the central and southern edge areas. Surface temperature (ST), Digital Elevation Map (DEM), and Green normalized difference vegetation index (GNDVI) are the most influential factors determining the spatial distribution of ecological risks in QMNPQA. The effects of management and climatic factors on ecological risks demonstrate a significant antagonistic effect, highlighting the positive contributions of human activities in mitigating the driving effects of climate change on ecological risks. The research results can provide reference for desertification prevention and ecological quality improvement in QMNPQA.


Assuntos
Mudança Climática , Conservação dos Recursos Naturais , Ecossistema , Atividades Humanas , Parques Recreativos , China , Humanos , Ecologia
8.
J Environ Manage ; 370: 122594, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39303594

RESUMO

Spatially differentiated conservation effort for natural resources is critical to achieving a balance between protection and development in national parks. However, the extent of priority conservation areas for plants that integrate multispecies and multifaceted values is unclear. Here, we selected fine-resolution environmental variables with stronger impacts on wild plant survival to spatialize the distribution of all modeling-eligible species using species distribution models in Three-River-Source National Park, China. These were then combined with in situ conservation results for insufficient data species to identify priority conservation areas (PCAs) in terms of diversity, ecological and economic values, respectively. We analyzed the spatial characteristics of the priority conservation areas and searched for conservation gaps not covered by national nature reserves. The results showed that this study obtained more precise results on the spatial distribution of species by improving environmental variables and upgrading the spatial resolution. In Three-River-Source National Park, the species richness of wild plants showed a decreasing trend from southeast to northwest. There were significant differences in the spatial distribution of the priority conservation areas identified based on the three values, which was the basis for the spatially differentiated conservation and development of wild plant resources. In addition, the priority conservation areas obtained based on ecological value found Top17% priority conservation areas in the Hoh Xil Natural Reserve, which could not be revealed based on diversity or economic value. These results highlight the urgency of implementing multispecies and multifaceted values studies in national parks. In the future, studying conflicts between wildlife priority conservation areas and human activities, and expanding to national parks on a global scale, will be the focus that this study will continue to explore.

9.
Mol Ecol ; 32(2): 504-517, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36318600

RESUMO

Anthropogenic changes to land use drive concomitant changes in biodiversity, including that of the soil microbiota. However, it is not clear how increasing intensity of human disturbance is reflected in the soil microbial communities. To address this issue, we used amplicon sequencing to quantify the microbiota (bacteria and fungi) in the soil of forests (n = 312) experiencing four different land uses, national parks (set aside for nature conservation), managed (for forestry purposes), suburban (on the border of an urban area) and urban (fully within a town or city), which broadly represent a gradient of anthropogenic disturbance. Alpha diversity of bacteria and fungi increased with increasing levels of anthropogenic disturbance, and was thus highest in urban forest soils and lowest in the national parks. The forest soil microbial communities were structured according to the level of anthropogenic disturbance, with a clear urban signature evident in both bacteria and fungi. Despite notable differences in community composition, there was little change in the predicted functional traits of urban bacteria. By contrast, urban soils exhibited a marked loss of ectomycorrhizal fungi. Soil pH was positively correlated with the level of disturbance, and thus was the strongest predictor of variation in alpha and beta diversity of forest soil communities, indicating a role of soil alkalinity in structuring urban soil microbial communities. Hence, our study shows how the properties of urban forest soils promote an increase in microbial diversity and a change in forest soil microbiota composition.


Assuntos
Micorrizas , Solo , Humanos , Solo/química , Florestas , Fungos/genética , Bactérias/genética , Biodiversidade , Microbiologia do Solo
10.
Glob Chang Biol ; 29(20): 5866-5880, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37489280

RESUMO

Understanding the resilience of ecosystems globally is hampered by the complex and interacting drivers of change characteristic of the Anthropocene. This is true for drylands of the western US, where widespread alteration of disturbance regimes and spread of invasive non-native species occurred with westward expansion during the 1800s, including the introduction of domestic livestock and spread of Bromus tectorum, an invasive non-native annual grass. In addition, this region has experienced a multi-decadal drought not seen for at least 1200 years with potentially large and interacting impacts on native plant communities. Here, we present 24 years of twice-annual plant cover monitoring (1997-2021) from a semiarid grassland never grazed by domestic livestock but subject to a patchy invasion of B. tectorum beginning in ~1994, compare our findings to surveys done in 1967, and examine potential climate drivers of plant community changes. We found a significant warming trend in the study area, with more than 75% of study year temperatures being warmer than average (1966-2021). We observed a native perennial grass community with high resilience to climate forcings with cover values like those in 1967. In invaded patches, B. tectorum cover was greatest in the early years of this study (1997-2001; ~20%-40%) but was subsequently constrained by climate and subtle variation in soils, with limited evidence of long-term impacts to native vegetation, contradicting earlier studies. Our ability to predict year-to-year variation in functional group and species cover with climate metrics varied, with a 12-month integrated index and fall and winter patterns appearing most important. However, declines to near zero live cover in recent years in response to regional drought intensification leave questions regarding the resiliency of intact grasslands to ongoing aridification and whether the vegetation observations reported here may be a leading indicator of impending change in this protected ecosystem.


Assuntos
Ecossistema , Pradaria , Secas , Poaceae , Bromus/fisiologia , Plantas , Espécies Introduzidas
11.
Ecol Appl ; 33(1): e2735, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36057540

RESUMO

The ecological integrity of US national parks and other protected areas are under threat in the Anthropocene. For Yellowstone National Park (YNP), the impacts that global change has already had on the park's capacity to sustain its large migratory herds of wild ungulates is incompletely understood. Here we examine how two understudied components of global change, the historical increase in atmospheric CO2 and the spread of nonnative, invasive plant species, may have altered the capacity of YNP to provide forage for ungulates over the last 200-plus years. We performed two experiments: (1) a growth chamber study that determined the growth rates of important invasive and native YNP grasses that are forages for ungulates under preindustrial (280 ppm) versus modern (410 ppm) CO2 levels and (2) a field study that compared the effect of defoliation (clipping) on the shoot growth of invasive and native mesic grassland plants under ambient CO2 conditions in 2019. The growth chamber experiment revealed that modern CO2 increased the growth rates of both invasive and native grasses, and invasive grasses grew faster regardless of CO2 conditions. The field results showed a continuum of positive to negative responses of shoot growth to defoliation, with a subgroup of invasive species responding most positively. Altogether the results indicated that the historical increase in CO2 and the spread of invasive species, some of which were planted to provide forage for ungulates in the early and mid-1900s, have likely increased the capacity of forage production in YNP. However, rising CO2 has also resulted in regional warming and increased aridity in YNP, which will likely reduce grassland productivity. The challenge for global change biologists and park managers is to determine how competing components of global change have already affected and will increasingly affect forage dynamics and the sustainability of Yellowstone's iconic ungulate herds in the Anthropocene.


Assuntos
Dióxido de Carbono , Mamíferos , Animais , Espécies Introduzidas , Poaceae
12.
Ecol Appl ; 33(4): e2837, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36890590

RESUMO

Advanced regeneration, in the form of tree seedlings and saplings, is critical for ensuring the long-term viability and resilience of forest ecosystems in the eastern United States. Lack of regeneration and/or compositional mismatch between regeneration and canopy layers, called regeneration debt, can lead to shifts in forest composition, structure, and, in extreme cases, forest loss. In this study, we examined status and trends in regeneration across 39 national parks from Virginia to Maine, spanning 12 years to apply the regeneration debt concept. We further refined the concept by adding new metrics and classifying results into easily interpreted categories adapted from the literature: imminent failure, probable failure, insecure, and secure. We then used model selection to determine the potential drivers most influencing patterns of regeneration debt. Status and trends indicated widespread regeneration debt in eastern national parks, with 27 of 39 parks classified as imminent or probable failure. Deer browse impact was consistently the strongest predictor of regeneration abundance. The most pervasive component of regeneration debt observed across parks was a sapling bottleneck, characterized by critically low sapling density of native canopy species and significant declines in native canopy sapling basal area or density for most parks. Regeneration mismatches also threaten forest resilience in many parks, where native canopy seedlings and saplings were outnumbered by native subcanopy species, particularly species that are less palatable deer browse. The devastating impact of emerald ash borer eliminating ash as a native canopy tree also drove regeneration mismatches in many parks that contain abundant ash regeneration, demonstrating the vulnerability of forests that lack diverse understories to invasive pests and pathogens. These findings underscore the critical importance of an integrated forest management approach that promotes an abundant and diverse regeneration layer. In most cases, this can only be achieved through long-term (i.e., multidecadal) management of white-tailed deer and invasive plants. Small-scale disturbances that increase structural complexity may also promote regeneration where stress from deer and invasive plants is minimal. Without immediate and sustained management intervention, the forest loss we are already observing may become a widespread pattern in eastern national parks and the broader region.


Assuntos
Cervos , Ecossistema , Animais , Parques Recreativos , Florestas , Árvores , Plântula , Maine
13.
Ecol Appl ; 33(2): e2758, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36193873

RESUMO

In the context of global decline in old-growth forest, historical ecology is a valuable tool to derive insights into vegetation legacies and dynamics and develop new conservation and restoration strategies. In this cross-disciplinary study, we integrate palynology (Lago del Pesce record), history, dendrochronology, and historical and contemporary land cover maps to assess drivers of vegetation change over the last millennium in a Mediterranean mountain forest (Pollino National Park, southern Italy) and discuss implications in conservation ecology. The study site hosts a remnant beech-fir (Fagus sylvatica-Abies alba) mixed forest, a priority habitat for biodiversity conservation in Europe. In the 10th century, the pollen record showed an open environment that was quickly colonized by silver fir when sociopolitical instabilities reduced anthropogenic pressures in mountain forests. The highest forest cover and biomass was reached between the 14th and the 17th centuries following land abandonment due to recurring plague pandemics. This rewilding process is also reflected in the recruitment history of Bosnian pine (Pinus heldreichii) in the subalpine elevation belt. Our results show that human impacts have been one of the main drivers of silver fir population contraction in the last centuries in the Mediterranean, and that the removal of direct human pressure led to ecosystem renovation. Since 1910, the Rubbio State Forest has locally protected and restored the mixed beech-fir forest. The institutions in 1972 for the Rubbio Natural Reserve and in 1993 for Pollino National Park have guaranteed the survival of the silver fir population, demonstrating the effectiveness of targeted conservation and restoration policies despite a warming climate. Monitoring silver fir populations can measure the effectiveness of conservation measures. In the last decades, the abandonment of rural environments (rewilding) along the mountains of southern Italy has reduced the pressure on ecosystems, thus boosting forest expansion. However, after four decades of natural regeneration and increasing biomass, pollen influx and forest composition are still far from the natural attributes of the medieval forest ecosystem. We conclude that long-term forest planning encouraging limited direct human disturbance will lead toward rewilding and renovation of carbon-rich and highly biodiverse Mediterranean old-growth forests, which will be more resistant and resilient to future climate change.


Assuntos
Ecossistema , Fagus , Humanos , Florestas , Europa (Continente) , Ecologia , Itália , Árvores
14.
J Anim Ecol ; 92(7): 1294-1305, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36287145

RESUMO

Fire regimes are expected to change with climate change, resulting in a crucial need to understand the specific ways in which variable fire regimes impact important contributors to ecosystem functioning, such as mound-building termites. Termite mounds and fire are both important agents of savanna ecosystem heterogeneity and functioning, but there is little understanding of how they interact across savanna types. We used very high-resolution LiDAR remote sensing to measure the size and distribution of termite mounds across approximately 1300 ha of experimental burn plots in four South African savanna landscapes representing a wide range of fire treatments differing in seasonality and frequency of burning. In nutrient-poor granitic savannas, fire had no impact on termite mound size, densities and spatial distributions. In nutrient-rich basaltic savannas with high mammalian herbivore abundance and intermediate rainfall, very frequent fires caused a decrease in termite mound size, whereas in arid nutrient-rich basaltic savannas, fires that occurred at intermediate frequencies and in transitional seasons (i.e. late dry season and late wet season) decreased the degree of spatial overdispersal exhibited by mounds. Overall, our results suggest that termite mounds are resistant to variation in fire seasonality and frequency, likely indicating that ecosystem services provided by mound-building termites will be unaffected by changing fire regimes. However, consideration of changes to termite mound size and distribution could be necessary for land managers in specific savanna types, such as nutrient-rich soils with high mammalian herbivore abundance.


Assuntos
Incêndios , Isópteros , Animais , Ecossistema , Pradaria , Solo , Mamíferos
15.
Environ Res ; 216(Pt 2): 114617, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36273598

RESUMO

Antibiotic resistant bacteria (ARB) have been detected in remote environments, but the degree to which their presence is due to anthropogenic contamination remains unclear. Here, anthropogenic and ecological determinants of ARB were characterized in remote and highly visited areas of Rocky Mountain National Park in the United States. Soil and water samples were collected from 29 sites once a month for three months and measured for bacteria resistant to seven antibiotics with flow cytometry. A novel index of the likelihood of human presence (HPI) was generated for estimating human impact on ARB abundance. The HPI accounted for 44% of variation in ARB abundance in water samples (p < 0.0001) and 51% of variation in soil samples (p < 0.00001). Human presence index was illustrated as a reliable predictor of ARB abundance despite a tendency to underpredict at higher levels of human impact. Ecological determinants such as temperature, elevation, slope, and aspect were also found to be significantly associated with ARB abundance. These findings suggest that human presence drives the abundance of ARB in Rocky Mountain National Park, but ecological variables play a significant role in their presence and dispersal.


Assuntos
Antibacterianos , Bactérias , Farmacorresistência Bacteriana , Humanos , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Genes Bacterianos , Efeitos Antropogênicos , Microbiologia do Solo , Microbiologia da Água , Estados Unidos , Monitoramento Ambiental
16.
Environ Res ; 216(Pt 1): 114439, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36174760

RESUMO

Abundant reserves of metals and oil have spurred large-scale mining developments across northwestern Canada during the past 80 years. Historically, the associated emissions footprint of hazardous metal(loid)s has been difficult to identify, in part, because monitoring records are too short and sparse to have characterized their natural concentrations before mining began. Stratigraphic analysis of lake sediment cores has been employed where concerns of pollution exist to determine pre-disturbance metal(loid) concentrations and quantify the degree of enrichment since mining began. Here, we synthesize the current state of knowledge via systematic re-analysis of temporal variation in sediment metal(loid) concentrations from 51 lakes across four key regions spanning 670 km from bitumen mining in the Alberta Oil Sands Region (AOSR) to gold mining (Giant and Con mines) at Yellowknife in central Northwest Territories. Our compilation includes upland and floodplain lakes at varying distances from the mines to evaluate dispersal of pollution-indicator metal(loid)s from bitumen (vanadium and nickel) and gold mining (arsenic and antimony) via atmospheric and fluvial pathways. Results demonstrate 'severe' enrichment of vanadium and nickel at near-field sites (≤20 km) within the AOSR and 'severe' (near-field; ≤ 40 km) to 'considerable' (far-field; 40-80 km) enrichment of arsenic and antimony due to gold mining at Yellowknife via atmospheric pathways, but no evidence of enrichment of vanadium or nickel via atmospheric or fluvial pathways at the Peace-Athabasca Delta and Slave River Delta. Findings can be used by decision makers to evaluate risks associated with contaminant dispersal by the large-scale mining activities. In addition, we reflect upon methodological approaches to be considered when evaluating paleolimnological data for evidence of anthropogenic contributions to metal(loid) deposition and advocate for proactive inclusion of paleolimnology in the early design stage of environmental contaminant monitoring programs.


Assuntos
Arsênio , Poluentes Químicos da Água , Campos de Petróleo e Gás , Ouro/análise , Poluentes Químicos da Água/análise , Vanádio , Níquel , Arsênio/análise , Antimônio , Mineração , Lagos , Monitoramento Ambiental/métodos , Alberta
17.
Sensors (Basel) ; 23(8)2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37112437

RESUMO

Tablas de Daimiel National Park (TDNP) is a unique inland wetland located in the Mancha plain (Spain). It is recognized at the international level, and it is protected by different figures, such as Biosphere Reserve. However, this ecosystem is endangered due to aquifer overexploitation, and it is at risk of losing its protection figures. The objective of our study is to analyze the evolution of the flooded area between the year 2000 and 2021 by Landsat (5, 7 and 8) and Sentinel-2 images, and to assess the TDNP state through an anomaly analysis of the total water body surface. Several water indices were tested, but the NDWI index for Sentinel-2 (threshold -0.20), the MNDWI for Landsat-5 (threshold -0.15), and the MNDWI for Landsat-8 (threshold -0.25) showed the highest accuracy to calculate the flooded surface inside the protected area's limits. During the period 2015-2021, we compared the performance of Landsat-8 and Sentinel-2 and an R2 value of 0.87 was obtained for this analysis, indicating a high correspondence between both sensors. Our results indicate a high variability of the flooded areas during the analyzed period with significant peaks, the most notorious in the second quarter of 2010. Minimum flooded areas were observed with negative precipitation index anomalies since fourth quarter of 2004 to fourth quarter of 2009. This period corresponds to a severe drought that affected this region and caused important deterioration. No significant correlation was observed between water surface anomalies and precipitation anomalies, and the significant correlation with flow and piezometric anomalies was moderate. This can be explained because of the complexity of water uses in this wetland, which includes illegal wells and the geological heterogeneity.

18.
J Fish Biol ; 103(3): 557-573, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37026429

RESUMO

For many decades, Nannocharax luapulae has been considered to be widespread in the southern part of the Upper Congo basin. However, meristic, morphometric and cytochrome c oxidase subunit I (COI) barcoding evidence revealed that its geographical distribution is restricted to the Luapula-Moero basin. The populations of the Upper Lualaba are assigned to a new species, N. chochamandai. This new species, though highly similar to N. luapulae, can readily be distinguished from it by its lower number of lateral line scales, 41-46 (vs. 49-55), its pectoral fin reaching the pelvic-fin insertion (vs. not reaching the pelvic-fin insertion) and its pelvic fin reaching the base of the anal fin (vs. not reaching the base of the anal fin). Specimens of N. chochamandai display thickened pads on the first three pelvic-fin rays that exhibit intraspecific variation in development, which appears to be related to the flow-strength of the river in which these Nannocharax specimens occur. Nannocharax luapulae is redescribed and an updated identification key to the Nannocharax species of the Congo basin sensu lato is provided as well. Some fish conservation issues related to N. luapulae and N. chochamandai are also highlighted.


Assuntos
Caraciformes , Animais , Congo , Rios , Pele
19.
Int J Mol Sci ; 24(9)2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37175744

RESUMO

Lavandula austroapennina N.G. Passal., Tundis and Upon has recently been described as a new species endemic to the southern Apennines (Italy). Locally, this species has a long ethnobotanical tradition of use for curative and decoration purposes and has been the protagonist of a flourishing essential oil production chain. Currently, while this tradition has long since ended, attention to the species is necessary, with a view to enhancing marginal and rural areas, as a recovery of a precious resource to (i) get insights into its (poly)phenolic fraction and (ii) address new and innovative uses of all its organs in various application fields (e.g., cosmeceutical sector). Therefore, after field sampling and dissection of its organs (i.e., corolla, calyx, leaf, stem and root), the latter, previously deterpenated and defatted, were subjected to accelerated ultrasound extraction and the related alcoholic extracts were obtained. Chemical composition, explored by UHPLC-QqTOF-MS/MS, and the following multivariate data analysis showed that the hydroxycinnamoyl derivatives are abundant in the leaf, stem and root, while flavonoids are more present in corolla and calyx. In particular, coumaroyl flavonoids with glyconic portion containing also hexuronyl moieties differentiated corolla organ, while yunnaneic acid D isomers and esculin distinguished root. When antiradical and reducing properties were evaluated (by means of ABTS, DPPH and PFRAP tests), a similar clustering of organs was achieved and the marked antioxidant efficacy of leaf, stem and root extracts was found. Thus, following cytotoxicity screening by MTT test on HaCaT keratinocytes, the protective effects of the organ extracts were assessed by wound closure observed after the scratch test. In addition, the extracts from corolla, leaf and stem were particularly active at low doses inducing rapid wound closure on HaCaT cells at a concentration of 1 µg/mL. The diversity in (poly)phenols of each organ and the promising bioactivity preliminarily assessed suggest further investigation to be carried out to fully recover and valorize this precious endemic vascular plant.


Assuntos
Lamiaceae , Lavandula , Polifenóis , Lavandula/química , Espectrometria de Massas em Tandem , Extratos Vegetais/química , Flavonoides/farmacologia , Flavonoides/análise , Antioxidantes/química
20.
J Environ Manage ; 329: 117086, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36565497

RESUMO

The contradiction between ecological conservation and economic development posed significant challenges to the management of National Parks. From the perspective of Ecological Economics, the cause of the contradiction is the difficulty of creating monetary profits from biodiversity conservation, which is the primary target of National Parks. Integrating Ecosystem Services (ESs) into space boundary delimitation is the next step in National Park management since ESs are closely related to human well-being and can provide monetary benefits. Extending the boundary of the National Park to high-ES areas and promoting ES trading can help generate funds for ecological restoration. Using the Sanjiangyuan National Park (SNP) as an example, this study proposed integrating ESs into National Park delimitation for sustainable National Park management. It was found that the current SNP boundary provides insufficient coverage of high-ES areas, while most of the multiple ES supply areas were dispersed to SNP's southeast edge. The Core conservation area showed the most prominent contradiction between ecological conservation and economic development, resulting in many low-level ES sites in the Traditional use area failing to be included in the Restoration area for protection. Future approaches would be well-advised to re-adjust SNP boundary by expanding the ES hotspot areas on the southeastern edge of SNP, as well as expanding funding sources via ecological product trade and other tools to supplement the input for ecological restoration. Overall, this study can act as a reference for optimizing National Parks within and beyond China, and promote the understanding of the Ecological Economy and sustainable development.


Assuntos
Ecossistema , Parques Recreativos , Humanos , Conservação dos Recursos Naturais/métodos , Biodiversidade , China
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