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1.
Anal Chem ; 96(25): 10237-10245, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38870418

RESUMO

Dot-blot immunoassays are widely used for the user-friendly detection of clinical biomarkers. However, the majority of dot-blot assays have only limited sensitivity and are only used for qualitative or semiquantitative analysis. To overcome this limitation, we have employed labels based on photon-upconversion nanoparticles (UCNPs) that exhibit anti-Stokes luminescence and can be detected without optical background interference. First, the dot-blot immunoassay on a nitrocellulose membrane was optimized for the quantitative analysis of human serum albumin (HSA), resulting in a limit of detection (LOD) of 0.19 ng/mL and a signal-to-background ratio (S/B) of 722. Commercial quantum dots were used as a reference label, reaching the LOD of 4.32 ng/mL and the S/B of 3, clearly indicating the advantages of UCNPs. In addition, the potential of UCNP-based dot-blot for real sample analysis was confirmed by analyzing spiked urine samples, reaching the LOD of 0.24 ng/mL and recovery rates from 79 to 123%. Furthermore, we demonstrated the versatility and robustness of the assay by adapting it to the detection of two other clinically relevant biomarkers, prostate-specific antigen (PSA) and cardiac troponin (cTn), reaching the LODs in spiked serum of 9.4 pg/mL and 0.62 ng/mL for PSA and cTn, respectively. Finally, clinical samples of patients examined for prostate cancer were analyzed, achieving a strong correlation with the reference electrochemiluminescence immunoassay (recovery rates from 89 to 117%). The achieved results demonstrate that UCNPs are highly sensitive labels that enable the development of dot-blot immunoassays for quantitative analysis of low-abundance biomarkers.


Assuntos
Biomarcadores , Limite de Detecção , Nanopartículas , Antígeno Prostático Específico , Humanos , Imunoensaio/métodos , Nanopartículas/química , Antígeno Prostático Específico/sangue , Antígeno Prostático Específico/análise , Biomarcadores/sangue , Biomarcadores/urina , Biomarcadores/análise , Pontos Quânticos/química , Albumina Sérica Humana/análise , Albumina Sérica Humana/urina , Masculino
2.
New Phytol ; 242(3): 1018-1028, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38436203

RESUMO

Biodiversity world-wide has been under increasing anthropogenic pressure in the past century. The long-term response of biotic communities has been tackled primarily by focusing on species richness, community composition and functionality. Equally important are shifts between entire communities and habitat types, which remain an unexplored level of biodiversity change. We have resurveyed > 2000 vegetation plots in temperate forests in central Europe to capture changes over an average of five decades. The plots were assigned to eight broad forest habitat types using an algorithmic classification system. We analysed transitions between the habitat types and interpreted the trend in terms of changes in environmental conditions. We identified a directional shift along the combined gradients of canopy openness and soil nutrients. Nutrient-poor open-canopy forest habitats have declined strongly in favour of fertile closed-canopy habitats. However, the shift was not uniform across the whole gradients. We conclude that the shifts in habitat types represent a century-long successional trend with significant consequences for forest biodiversity. Open forest habitats should be urgently targeted for plant diversity restoration through the implementation of active management. The approach presented here can be applied to other habitat types and at different spatio-temporal scales.


Assuntos
Ecossistema , Florestas , Biodiversidade , Plantas , Biota
3.
Ann Bot ; 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38407819

RESUMO

BACKGROUND AND AIMS: Understanding biomass allocation among plant organs is crucial for comprehending plant growth optimization, survival and responses to global change drivers. Yet, mechanisms governing mass allocation in vascular plants from extreme elevations exposed to cold and drought stresses remain poorly understood. METHODOLOGY: We analyzed organ mass weights and fractions in 258 Himalayan herbaceous species across diverse habitats (wetland, steppe, alpine), growth forms (annual, perennial taprooted, rhizomatous, cushiony), and climatic gradients (3500-6150 m elevation) to explore whether biomass distribution adhered to fixed allometric or optimal partitioning rules, and how variation in size, phylogeny, and ecological preferences influence their strategies for resource allocation. KEY FINDINGS: Following the optimal partitioning theory, Himalayan plants distribute more biomass to key organs vital for acquiring and preserving limited resources necessary for their growth and survival. Allocation strategies are mainly influenced by plant growth forms and habitat conditions, notably temperature, water availability, and evaporative demands. Alpine plants primarily invest in belowground stem bases for storage and regeneration, reducing aboveground stems while increasing leaf mass fraction to maximize carbon assimilation in their short growing season. Conversely, arid steppe plants prioritize deep roots over leaves to secure water and minimize transpiration. Wetland plants allocate resources to aboveground stems and belowground rhizomes, enabling them to resist competition and grazing in fertile environments. CONCLUSIONS: Himalayan plants from extreme elevations optimize their allocation strategies to acquire scarce resources under specific conditions, efficiently investing carbon from supportive to acquisitive and protective functions with increasing cold and drought. Intraspecific variation and shared ancestry did not significantly alter Himalayan plants' biomass allocation strategies. Despite diverse evolutionary histories, plants from similar habitats have developed comparable phenotypic structures to adapt to their specific environments. This study offers new insights into plant adaptations in diverse Himalayan environments and underscores the importance of efficient resource allocation for survival and growth in challenging conditions.

4.
Glob Chang Biol ; 30(1): e17086, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38273496

RESUMO

Plant communities are being exposed to changing environmental conditions all around the globe, leading to alterations in plant diversity, community composition, and ecosystem functioning. For herbaceous understorey communities in temperate forests, responses to global change are postulated to be complex, due to the presence of a tree layer that modulates understorey responses to external pressures such as climate change and changes in atmospheric nitrogen deposition rates. Multiple investigative approaches have been put forward as tools to detect, quantify and predict understorey responses to these global-change drivers, including, among others, distributed resurvey studies and manipulative experiments. These investigative approaches are generally designed and reported upon in isolation, while integration across investigative approaches is rarely considered. In this study, we integrate three investigative approaches (two complementary resurvey approaches and one experimental approach) to investigate how climate warming and changes in nitrogen deposition affect the functional composition of the understorey and how functional responses in the understorey are modulated by canopy disturbance, that is, changes in overstorey canopy openness over time. Our resurvey data reveal that most changes in understorey functional characteristics represent responses to changes in canopy openness with shifts in macroclimate temperature and aerial nitrogen deposition playing secondary roles. Contrary to expectations, we found little evidence that these drivers interact. In addition, experimental findings deviated from the observational findings, suggesting that the forces driving understorey change at the regional scale differ from those driving change at the forest floor (i.e., the experimental treatments). Our study demonstrates that different approaches need to be integrated to acquire a full picture of how understorey communities respond to global change.


Assuntos
Ecossistema , Florestas , Árvores , Plantas , Nitrogênio
5.
Nat Commun ; 15(1): 549, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38263406

RESUMO

Temperature is a fundamental driver of species distribution and ecosystem functioning. Yet, our knowledge of the microclimatic conditions experienced by organisms inside tropical forests remains limited. This is because ecological studies often rely on coarse-gridded temperature estimates representing the conditions at 2 m height in an open-air environment (i.e., macroclimate). In this study, we present a high-resolution pantropical estimate of near-ground (15 cm above the surface) temperatures inside forests. We quantify diurnal and seasonal variability, thus revealing both spatial and temporal microclimate patterns. We find that on average, understory near-ground temperatures are 1.6 °C cooler than the open-air temperatures. The diurnal temperature range is on average 1.7 °C lower inside the forests, in comparison to open-air conditions. More importantly, we demonstrate a substantial spatial variability in the microclimate characteristics of tropical forests. This variability is regulated by a combination of large-scale climate conditions, vegetation structure and topography, and hence could not be captured by existing macroclimate grids. Our results thus contribute to quantifying the actual thermal ranges experienced by organisms inside tropical forests and provide new insights into how these limits may be affected by climate change and ecosystem disturbances.


Assuntos
Ecossistema , Florestas , Temperatura , Mudança Climática , Sistemas Computacionais
6.
New Phytol ; 241(5): 2287-2299, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38126264

RESUMO

Global change has accelerated local species extinctions and colonizations, often resulting in losses and gains of evolutionary lineages with unique features. Do these losses and gains occur randomly across the phylogeny? We quantified: temporal changes in plant phylogenetic diversity (PD); and the phylogenetic relatedness (PR) of lost and gained species in 2672 semi-permanent vegetation plots in European temperate forest understories resurveyed over an average period of 40 yr. Controlling for differences in species richness, PD increased slightly over time and across plots. Moreover, lost species within plots exhibited a higher degree of PR than gained species. This implies that gained species originated from a more diverse set of evolutionary lineages than lost species. Certain lineages also lost and gained more species than expected by chance, with Ericaceae, Fabaceae, and Orchidaceae experiencing losses and Amaranthaceae, Cyperaceae, and Rosaceae showing gains. Species losses and gains displayed no significant phylogenetic signal in response to changes in macroclimatic conditions and nitrogen deposition. As anthropogenic global change intensifies, temperate forest understories experience losses and gains in specific phylogenetic branches and ecological strategies, while the overall mean PD remains relatively stable.


Les changements globaux accélèrent les processus de colonisation et d'extinction locales d'espèces, aboutissant à des gains ou à des pertes de lignées évolutives uniques. Ces gains et pertes se produisent-ils de manière aléatoire dans l'arbre phylogénétique ? Nous avons mesuré: les changements de diversité phylogénétique; et la parenté phylogénétique des espèces végétales gagnées ou perdues dans 2672 placettes semi-permanentes disposées dans le sous-bois de forêts tempérées d'Europe sur une période moyenne de 40 ans. Une fois corrigée par la richesse spécifique, la diversité phylogénétique a légèrement augmenté au cours du temps dans les différentes placettes. Les espèces perdues ont une plus grande parenté phylogénétique que les espèces gagnées. Les espèces gagnées sont donc issues d'un plus grand nombre de lignées évolutives que les espèces perdues. Certaines lignées ont gagné ou perdu davantage d'espèces que ce qui est prédit par le hasard : les Ericaceae, les Fabaceae et les Orchidaceae ayant davantage perdu, tandis que les Amaranthaceae, les Cyperaceae, et les Rosaceae ont plus gagné. Il n'y a pas de signal phylogénétique des gains ou pertes d'espèces en réponse aux changements de conditions macroclimatiques ou des dépôts atmosphériques d'azote. Alors que les changements globaux d'origine anthropique s'intensifient, les sous-bois des forêts tempérées connaissent des gains et des pertes de certaines lignées évolutives et de certaines stratégies écologiques, sans que la diversité phylogénétique moyenne ne s'en trouve véritablement affectée.


El cambio global ha acelerado las extinciones y colonizaciones a escala local, lo que a menudo ha supuesto pérdidas y ganancias de linajes evolutivos con características únicas. Ahora bien, ¿estas pérdidas y ganancias ocurren aleatoriamente a lo largo de la filogenia? Cuantificamos: los cambios temporales en la diversidad filogenética de las plantas; y la relación filogenética de las especies perdidas y ganadas en 2.672 parcelas de vegetación semipermanente en sotobosques templados europeos y re-muestreadas durante un período promedio de 40 años. Al controlar por las diferencias en la riqueza de especies, la diversidad filogenética aumentó ligeramente con el tiempo y entre parcelas. Además, las especies perdidas dentro de las parcelas exhibieron un mayor grado de relación filogenética que las especies ganadas. Esto implica que las especies ganadas se originaron en un conjunto de linajes evolutivos más diversos que las especies perdidas. Ciertos linajes también perdieron y ganaron más especies de las esperadas aleatoriamente: Ericaceae, Fabaceae y Orchidaceae experimentaron pérdidas y Amaranthaceae, Cyperaceae y Rosaceae mostraron ganancias. Las pérdidas y ganancias de especies no mostraron ninguna señal filogenética significativa en respuesta a los cambios en las condiciones macro-climáticas y la deposición de nitrógeno. A medida que se intensifica el cambio global antropogénico, los sotobosques temperados experimentan pérdidas y ganancias en ramas filogenéticas y estrategias ecológicas específicas, mientras que la diversidad filogenética media general permanece relativamente estable.


Assuntos
Biodiversidade , Nitrogênio , Filogenia , Mudança Climática , Florestas , Plantas
7.
Ecol Lett ; 26(12): 2043-2055, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37788337

RESUMO

Species distributions are conventionally modelled using coarse-grained macroclimate data measured in open areas, potentially leading to biased predictions since most terrestrial species reside in the shade of trees. For forest plant species across Europe, we compared conventional macroclimate-based species distribution models (SDMs) with models corrected for forest microclimate buffering. We show that microclimate-based SDMs at high spatial resolution outperformed models using macroclimate and microclimate data at coarser resolution. Additionally, macroclimate-based models introduced a systematic bias in modelled species response curves, which could result in erroneous range shift predictions. Critically important for conservation science, these models were unable to identify warm and cold refugia at the range edges of species distributions. Our study emphasizes the crucial role of microclimate data when SDMs are used to gain insights into biodiversity conservation in the face of climate change, particularly given the growing policy and management focus on the conservation of refugia worldwide.


Assuntos
Florestas , Microclima , Árvores , Plantas , Biodiversidade , Mudança Climática , Ecossistema
8.
FEMS Microbiol Ecol ; 99(9)2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37562924

RESUMO

Arbuscular mycorrhizal (AM) fungi can benefit plants under environmental stress, and influence plant adaptation to warmer climates. However, very little is known about the ecology of these fungi in alpine environments. We sampled plant roots along a large fraction (1941-6150 m asl (above sea level)) of the longest terrestrial elevational gradient on Earth and used DNA metabarcoding to identify AM fungi. We hypothesized that AM fungal alpha and beta diversity decreases with increasing elevation, and that different vegetation types comprise dissimilar communities, with cultured (putatively ruderal) taxa increasingly represented at high elevations. We found that the alpha diversity of AM fungal communities declined linearly with elevation, whereas within-site taxon turnover (beta diversity) was unimodally related to elevation. The composition of AM fungal communities differed between vegetation types and was influenced by elevation, mean annual temperature, and precipitation. In general, Glomeraceae taxa dominated at all elevations and vegetation types; however, higher elevations were associated with increased presence of Acaulosporaceae, Ambisporaceae, and Claroideoglomeraceae. Contrary to our expectation, the proportion of cultured AM fungal taxa in communities decreased with elevation. These results suggest that, in this system, climate-induced shifts in habitat conditions may facilitate more diverse AM fungal communities at higher elevations but could also favour ruderal taxa.


Assuntos
Glomeromycota , Micorrizas , Micorrizas/genética , Simbiose , Ecossistema , Raízes de Plantas/microbiologia , Clima , Plantas , Microbiologia do Solo , Solo
9.
Glob Chang Biol ; 29(11): 2886-2892, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37128754

RESUMO

Microclimate research gained renewed interest over the last decade and its importance for many ecological processes is increasingly being recognized. Consequently, the call for high-resolution microclimatic temperature grids across broad spatial extents is becoming more pressing to improve ecological models. Here, we provide a new set of open-access bioclimatic variables for microclimate temperatures of European forests at 25 × 25 m2 resolution.


Assuntos
Microclima , Árvores , Temperatura , Florestas , Ecossistema
10.
Nat Commun ; 13(1): 7837, 2022 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-36550094

RESUMO

Ungulate populations are increasing across Europe with important implications for forest plant communities. Concurrently, atmospheric nitrogen (N) deposition continues to eutrophicate forests, threatening many rare, often more nutrient-efficient, plant species. These pressures may critically interact to shape biodiversity as in grassland and tundra systems, yet any potential interactions in forests remain poorly understood. Here, we combined vegetation resurveys from 52 sites across 13 European countries to test how changes in ungulate herbivory and eutrophication drive long-term changes in forest understorey communities. Increases in herbivory were associated with elevated temporal species turnover, however, identities of winner and loser species depended on N levels. Under low levels of N-deposition, herbivory favored threatened and small-ranged species while reducing the proportion of non-native and nutrient-demanding species. Yet all these trends were reversed under high levels of N-deposition. Herbivores also reduced shrub cover, likely exacerbating N effects by increasing light levels in the understorey. Eutrophication levels may therefore determine whether herbivory acts as a catalyst for the "N time bomb" or as a conservation tool in temperate forests.


Assuntos
Florestas , Herbivoria , Plantas , Biodiversidade , Nitrogênio
11.
Sci Total Environ ; 821: 153377, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35077798

RESUMO

Increasingly available high-resolution digital elevation models (DEMs) facilitate the use of fine-scale topographic variables as proxies for microclimatic effects not captured by the coarse-grained macroclimate datasets. Species distributions and community assembly rules are, however directly shaped by microclimate and not by topography. DEM-derived topography, sometimes combined with vegetation structure, is thus widely used as a proxy for microclimatic effects in ecological research and conservation applications. However, the suitability of such a strategy has not been evaluated against in situ measured microclimate and species composition. Because bryophytes are highly sensitive to microclimate, they are ideal model organisms for such evaluation. To provide this much needed evaluation, we simultaneously recorded bryophyte species composition, microclimate, and forest vegetation structure at 218 sampling sites distributed across topographically complex sandstone landscape. Using a LiDAR-based DEM with a 1 m resolution, we calculated eleven topographic variables serving as a topographic proxy for microclimate. To characterize vegetation structure, we used hemispherical photographs and LiDAR canopy height models. Finally, we calculated eleven microclimatic variables from a continuous two-year time- series of air and soil temperature and soil moisture. To evaluate topography and vegetation structure as substitutes for the ecological effect of measured microclimate, we partitioned the variation in bryophyte species composition and richness explained by microclimate, topography, and vegetation structure. In situ measured microclimate was clearly the most important driver of bryophyte assemblages in temperate coniferous forests. The most bryophyte-relevant variables were growing degree days, maximum air temperature, and mean soil moisture. Our results thus showed that topographic variables, even when derived from high-resolution LiDAR data and combined with in situ sampled vegetation structure, cannot fully substitute effects of in situ measured microclimate on forest bryophytes.


Assuntos
Briófitas , Microclima , Florestas , Solo , Temperatura , Árvores
12.
Glob Chang Biol ; 28(9): 3110-3144, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34967074

RESUMO

Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km2 resolution for 0-5 and 5-15 cm soil depth. These maps were created by calculating the difference (i.e. offset) between in situ soil temperature measurements, based on time series from over 1200 1-km2 pixels (summarized from 8519 unique temperature sensors) across all the world's major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (-0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications.


Assuntos
Ecossistema , Solo , Mudança Climática , Microclima , Temperatura
13.
Ecol Lett ; 25(2): 466-482, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34866301

RESUMO

Species turnover is ubiquitous. However, it remains unknown whether certain types of species are consistently gained or lost across different habitats. Here, we analysed the trajectories of 1827 plant species over time intervals of up to 78 years at 141 sites across mountain summits, forests, and lowland grasslands in Europe. We found, albeit with relatively small effect sizes, displacements of smaller- by larger-ranged species across habitats. Communities shifted in parallel towards more nutrient-demanding species, with species from nutrient-rich habitats having larger ranges. Because these species are typically strong competitors, declines of smaller-ranged species could reflect not only abiotic drivers of global change, but also biotic pressure from increased competition. The ubiquitous component of turnover based on species range size we found here may partially reconcile findings of no net loss in local diversity with global species loss, and link community-scale turnover to macroecological processes such as biotic homogenisation.


Assuntos
Biodiversidade , Pradaria , Ecossistema , Florestas , Plantas
14.
Glob Chang Biol ; 27(23): 6307-6319, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34605132

RESUMO

Ecological research heavily relies on coarse-gridded climate data based on standardized temperature measurements recorded at 2 m height in open landscapes. However, many organisms experience environmental conditions that differ substantially from those captured by these macroclimatic (i.e. free air) temperature grids. In forests, the tree canopy functions as a thermal insulator and buffers sub-canopy microclimatic conditions, thereby affecting biological and ecological processes. To improve the assessment of climatic conditions and climate-change-related impacts on forest-floor biodiversity and functioning, high-resolution temperature grids reflecting forest microclimates are thus urgently needed. Combining more than 1200 time series of in situ near-surface forest temperature with topographical, biological and macroclimatic variables in a machine learning model, we predicted the mean monthly offset between sub-canopy temperature at 15 cm above the surface and free-air temperature over the period 2000-2020 at a spatial resolution of 25 m across Europe. This offset was used to evaluate the difference between microclimate and macroclimate across space and seasons and finally enabled us to calculate mean annual and monthly temperatures for European forest understories. We found that sub-canopy air temperatures differ substantially from free-air temperatures, being on average 2.1°C (standard deviation ± 1.6°C) lower in summer and 2.0°C higher (±0.7°C) in winter across Europe. Additionally, our high-resolution maps expose considerable microclimatic variation within landscapes, not captured by the gridded macroclimatic products. The provided forest sub-canopy temperature maps will enable future research to model below-canopy biological processes and patterns, as well as species distributions more accurately.


Assuntos
Florestas , Microclima , Mudança Climática , Temperatura , Árvores
15.
Sci Total Environ ; 757: 143785, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33220998

RESUMO

Soil moisture controls environmental processes and species distributions, but it is difficult to measure and interpolate across space. Topographic Wetness Index (TWI) derived from digital elevation model is therefore often used as a proxy for soil moisture. However, different algorithms can be used to calculate TWI and this potentially affects TWI relationship with soil moisture and species assemblages. To disentangle insufficiently-known effects of different algorithms on TWI relation with soil moisture and plant species composition, we measured the root-zone soil moisture throughout a growing season and recorded vascular plants and bryophytes in 45 temperate forest plots. For each plot, we calculated 26 TWI variants from a LiDAR-based digital terrain model and related these TWI variants to the measured soil moisture and moisture-controlled species assemblages of vascular plants and bryophytes. A flow accumulation algorithm determined the ability of the TWI to predict soil moisture, while the flow width and slope algorithms had only a small effects. The TWI calculated with the most often used single-flow D8 algorithm explained less than half of the variation in soil moisture and species composition explained by the TWI calculated with the multiple-flow FD8 algorithm. Flow dispersion used in the FD8 algorithm strongly affected the TWI performance, and a flow dispersion close to 1.0 resulted in the TWI best related to the soil moisture and species assemblages. Using downslope gradient instead of the local slope gradient can strongly decrease TWI performance. Our results clearly showed that the method used to calculate TWI affects study conclusion. However, TWI calculation is often not specified and thus impossible to reproduce and compare among studies. We therefore provide guidelines for TWI calculation and recommend the FD8 flow algorithm with a flow dispersion close to 1.0, flow width equal to the raster cell size and local slope gradient for TWI calculation.


Assuntos
Plantas , Solo , Água/análise
16.
Science ; 370(6522)2020 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-33303585

RESUMO

Schall and Heinrichs question our interpretation that the climatic debt in understory plant communities is locally modulated by canopy buffering. However, our results clearly show that the discrepancy between microclimate warming rates and thermophilization rates is highest in forests where canopy cover was reduced, which suggests that the need for communities to respond to warming is highest in those forests.


Assuntos
Florestas , Microclima , Plantas
17.
Science ; 370(6520)2020 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-33243862

RESUMO

Bertrand et al question our interpretation about warming effects on the thermophilization in forest plant communities and propose an alternative way to analyze climatic debt. We show that microclimate warming is a better predictor than macroclimate warming for studying forest plant community responses to warming. Their additional analyses do not affect or change our interpretations and conclusions.


Assuntos
Florestas , Microclima , Plantas
18.
Science ; 368(6492): 772-775, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32409476

RESUMO

Climate warming is causing a shift in biological communities in favor of warm-affinity species (i.e., thermophilization). Species responses often lag behind climate warming, but the reasons for such lags remain largely unknown. Here, we analyzed multidecadal understory microclimate dynamics in European forests and show that thermophilization and the climatic lag in forest plant communities are primarily controlled by microclimate. Increasing tree canopy cover reduces warming rates inside forests, but loss of canopy cover leads to increased local heat that exacerbates the disequilibrium between community responses and climate change. Reciprocal effects between plants and microclimates are key to understanding the response of forest biodiversity and functioning to climate and land-use changes.


Assuntos
Florestas , Aquecimento Global , Microclima , Árvores/fisiologia , Europa (Continente)
19.
Nat Ecol Evol ; 4(6): 802-808, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32284580

RESUMO

Biodiversity time series reveal global losses and accelerated redistributions of species, but no net loss in local species richness. To better understand how these patterns are linked, we quantify how individual species trajectories scale up to diversity changes using data from 68 vegetation resurvey studies of seminatural forests in Europe. Herb-layer species with small geographic ranges are being replaced by more widely distributed species, and our results suggest that this is due less to species abundances than to species nitrogen niches. Nitrogen deposition accelerates the extinctions of small-ranged, nitrogen-efficient plants and colonization by broadly distributed, nitrogen-demanding plants (including non-natives). Despite no net change in species richness at the spatial scale of a study site, the losses of small-ranged species reduce biome-scale (gamma) diversity. These results provide one mechanism to explain the directional replacement of small-ranged species within sites and thus explain patterns of biodiversity change across spatial scales.


Assuntos
Ecossistema , Florestas , Biodiversidade , Europa (Continente) , Plantas
20.
Glob Chang Biol ; 26(11): 6616-6629, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32311220

RESUMO

Current analyses and predictions of spatially explicit patterns and processes in ecology most often rely on climate data interpolated from standardized weather stations. This interpolated climate data represents long-term average thermal conditions at coarse spatial resolutions only. Hence, many climate-forcing factors that operate at fine spatiotemporal resolutions are overlooked. This is particularly important in relation to effects of observation height (e.g. vegetation, snow and soil characteristics) and in habitats varying in their exposure to radiation, moisture and wind (e.g. topography, radiative forcing or cold-air pooling). Since organisms living close to the ground relate more strongly to these microclimatic conditions than to free-air temperatures, microclimatic ground and near-surface data are needed to provide realistic forecasts of the fate of such organisms under anthropogenic climate change, as well as of the functioning of the ecosystems they live in. To fill this critical gap, we highlight a call for temperature time series submissions to SoilTemp, a geospatial database initiative compiling soil and near-surface temperature data from all over the world. Currently, this database contains time series from 7,538 temperature sensors from 51 countries across all key biomes. The database will pave the way toward an improved global understanding of microclimate and bridge the gap between the available climate data and the climate at fine spatiotemporal resolutions relevant to most organisms and ecosystem processes.


Assuntos
Ecossistema , Microclima , Mudança Climática , Neve , Temperatura
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