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1.
Sci Total Environ ; 753: 142012, 2021 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-33207433

RESUMEN

Analysing the climate envelope of plant species has been suggested as a tool to predict the vulnerability of tree species in future urban climates. However, there is little evidence that the climate envelope of a plant species directly relates to the drought and thermal tolerance of that species, at least not at the resolution required to identify or rank species vulnerability. Here, we attempted to predict drought and thermal tolerance of commonly used urban tree species using climate variables derived exclusively from open-source global occurrence data. We quantified three drought and thermal tolerance traits for 43 urban tree species in a common garden experiment: stomatal sensitivity to vapour pressure deficit, leaf water potential at the turgor loss point, and leaf thermal tolerance. We then attempted to predict each tolerance trait from variables derived from the climate envelope of each species, using occurrence data from the Global Biodiversity Information Facility. We found no strong relationships between drought and thermal tolerance traits and climatic variables. Across wide environmental gradients, plant tolerance and climate are inherently linked. But our results suggest that climate envelopes determined from species occurrence data alone may not predict drought or thermal tolerance at the resolution required to select tree species for future urban forests. We should focus on identifying the most relevant strategies and traits required to describe tolerance which in combination with climate envelope analysis should ultimately predict growth and mortality of trees in urban landscapes.


Asunto(s)
Sequías , Árboles , Cambio Climático , Bosques , Hojas de la Planta , Agua
2.
Sci Total Environ ; 751: 142159, 2021 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-33181999

RESUMEN

A consistent and equitable global drought risk assessment for multiple regions, populations, and economic sectors at the gridded scale under future diverse climate change scenarios has been the subject of scarce research. Climate change is projected to increase the future hazard of drought and cause consequential damages to socioeconomic systems. The risk assessment of drought caused by climate change can be a bridge between impacts and adaptation. To assess the socioeconomic risk to droughts in a base period and two future periods (2016 to 2035 and 2046 to 2065), the projections of five general circulation models and population and gross domestic product (GDP), land cover, and water resources data were used to analyze the socioeconomic risk under three scenarios combining representative concentration pathways (RCPs) and shared socioeconomic pathways (SSPs). The socioeconomic risk was calculated as the product of three determinants: hazard, exposure, and vulnerability. The risk of the global population to drought was projected to be highest in 2046 to 2065 under scenario RCP8.5-SSP3, with up to 1.45 × 109 persons affected, a 63% increase compared with the base period. The highest risk to GDP (4.29 × 1013 purchasing power parity $) was possibly in 2046 to 2065 under scenario RCP2.6-SSP1, with the risk increasing 5.64 times compared to the base period. Regions with high socioeconomic risk were primarily concentrated in the East and South Asia, Midwestern Europe, eastern US, and the coastal areas of South America. With climate change, the inequality in future socioeconomic risk to drought among countries is predicted to increase. The ten countries with the highest risks to population and GDP accounted for nearly 70% of the global risk.


Asunto(s)
Sequías , Modelos Teóricos , Asia , Cambio Climático , Europa (Continente) , Factores Socioeconómicos , América del Sur
3.
Sci Total Environ ; 750: 142031, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33182219

RESUMEN

It is currently assumed that climate change related factors pose severe challenges to biodiversity maintenance. This paper assesses the multi-stressor effects of elevated temperature (15 °C as control, 25 °C as elevated) and CO2 levels (pH 8.1 as control, 7.5 and 7.0 representing acidifying conditions) on the physiological (survival and regenerative capacity), behavioral (feeding and burrowing activities), and biochemical changes (metabolic capacity, oxidative status and biotransformation mechanisms) experienced by the keystone polychaete Hediste diversicolor. Temperature rise enlarged the adverse effect of marine acidification on the survival of H. diversicolor, delayed the beginning of the excavation activity, enhancing the negative effects that pH decrease had in the burrowing behavior of this polychaete. Additionally, regardless of the temperature, exposure of H. diversicolor to acidification results in a reduction in the feeding rate. It is the first time that this decreased feeding capacity is found related to seawater acidification in this species. The healing of the wound and the blastemal formation were retarded due to these two climatic factors which hinder the regenerative process of polychaetes. These vital physiological functions of H. diversicolor can be related to the oxidative stress induced by climate change conditions since free radicals overproduced will impair cells functioning, affecting species biochemical and physiological performance, including feeding and tissue regeneration. The present results also demonstrated that although polychaetes' metabolic capacity was enhanced under stress conditions, organisms were still able to increase or maintain their energy reserves. Our findings are of major environmental relevance considering that predicted climate change conditions will affect species vital and ecological and physiological capacities. These can be translated into shrinking not only at the individual and population level but also in microbial and endofaunal diversities, in the detritus processing in estuaries and biogeochemical cycles at the ecosystem level. Thus the conservation of H. diversicolor populations is vital for the normal functioning of estuarine mudflat ecosystems.


Asunto(s)
Poliquetos , Contaminantes Químicos del Agua , Animales , Cambio Climático , Ecosistema , Agua de Mar
4.
Sci Total Environ ; 752: 142225, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33207503

RESUMEN

Methane (CH4) is one of the most important greenhouse gases which can be formed by methanogens and oxidized by methanotrophs, as well as ammonia oxidizers. Agricultural soils can be both a source and sink for atmospheric CH4. However, it is unclear how climate change, will affect CH4 emissions and the underlying functional guilds. In this field study, we determined the impact of simulated climate change (a warmer and drier condition) and its legacy effect on CH4 emissions and the methanogenic and methanotrophic communities, as well as their relationships with ammonia oxidizers in an acidic soil with urea application. The climate change conditions were simulated in a greenhouse, and the legacy effect was simulated by removing the greenhouse after twelve months. Simulated climate change significantly decreased the in situ CH4 emissions in the urea-treated soils while the legacy effect significantly decreased the in situ CH4 emissions in the control plots, but had very little effect in the urea-treated soils. This indicates that the impact of simulated climate change and its legacy on CH4 emissions was significantly modified by nitrogen fertilization. Methanotrophs were more sensitive than methanogens in response to simulated climate change and its legacy effect, especially in the urea treated soil. Significant negative correlations were observed between the abundances of ammonia oxidizers and methanotrophs. Additionally, results of partial least path modeling (PLS-PM) indicated that the interactions of methanogens and methanotrophs with ammonia oxidizing archaea (AOA) had significant positive relationships with in situ CH4 emissions under the simulated climate change condition. Our work highlights the important role of AOA for CH4 emissions under climate change conditions. Further research is needed to better understand this effect in other ecosystems.


Asunto(s)
Metano , Suelo , Amoníaco , Cambio Climático , Ecosistema , Microbiología del Suelo
5.
Sci Total Environ ; 750: 141147, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-32853939

RESUMEN

In recent decades, climate disasters, especially droughts and floods, have disrupted food production and caused yield losses. Crop models cannot identify quantitative changes of crop yield and production caused by climate disasters directly, and empirical approaches possibly underestimate the effects due to the use of the entire world or an individual nation as the unit of study. Here, we quantified the losses of crop yield and production resulting from droughts and floods across China during 1982-2012 using the superposed epoch analysis (SEA) method. We defined the actual-occurred and control composited series using provincial-level data in China, i.e., covered area (CA), affected area (AA), and sown area (SA) from 1982 to 2012, and crop yields and production of maize, rice, soybean, and wheat from 1979 to 2015. The results showed that maize and soybean in China suffered serious damage from droughts, with reductions in yields and production ranging from 7.8% to 11.6% between 1982 and 2012. Droughts and floods significantly decreased wheat yield by 5.8% and 6.1%, respectively. Moreover, rice yield and production were sensitive to both droughts and floods, with reductions of 4.5-6.3%. Among the MGPA, crops cultivated in NEC and the Huang-Huai-Hai Plain (HHH) were more easily affected by droughts. Among the four main crops and the three types of rice in the mid-lower reaches of the Yangtze River (MLYR), the yield and production of only early rice were sensitive to floods. The quantitative identification of the spatial responses of crop yields and production to droughts and floods can help us better understand the impacts of climate disasters on food security in China and the whole world, which is essential for addressing potential adaptation strategies.


Asunto(s)
Cambio Climático , Desastres , China , Clima , Sequías
6.
Sci Total Environ ; 751: 141721, 2021 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-32861948

RESUMEN

Globally, soils are subject to radical changes in their biogeochemistry as rampant deforestation and other forms of land use and climate change continue to transform planet Earth. To better understand soil ecosystem functioning, it is necessary to understand the responses of soil microbial diversity and community structure to changing climate, land cover, and associated environmental variables. With next-generation sequencing, we investigated changes in topsoil fungi community structure among different land cover types (from Forest to Cropland) and climate zones (from Hot to Cold zones) in the Western Pacific Region. We demonstrated that climate zones substantially (P = 0.001) altered the soil fungal beta-diversity (change in community composition), but not alpha-diversity (taxonomical diversity). In particular, precipitation, temperature, and also latitude were the best predictors of beta-diversity. Individual fungal classes displayed divergent but strong responses to climate variables and latitude, suggesting niche differentiation at lower taxonomic levels. We also demonstrated that fungal taxonomic diversity differentially responded to latitude across land covers: fungal diversity increased towards lower latitudes in the Forest and Cropland (R2 = 0.19) but increased towards both lower and higher latitudes in Fallow land (R2 = 0.45). Further, alpha-diversity was significantly influenced by soil pH in Forest (P = 0.02), and by diurnal temperature range in Fallow land and mean annual precipitation in Cropland. Collectively, various land cover types had differential influence on the latitude diversity gradient, while climate, and to some extent, edaphic variables, were crucial in shaping soil fungal community structure. Our results can also serve as a baseline for estimating global change impacts on fungal community structure in the Western Pacific Region.


Asunto(s)
Micobioma , Cambio Climático , Ecosistema , Bosques , Suelo , Microbiología del Suelo
7.
Sci Total Environ ; 750: 141736, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-32871374

RESUMEN

Climate change is expected to increase extreme weather events, such as more extreme drought and rainfall incidences, with consequences for ecosystem carbon (C) cycling. An understanding of how drying and rewetting (DRW) events affect microbe-mediated soil processes is therefore critical to the predictions of future climate. Here, a reciprocal-transplant experiment was conducted using two soils originated from distinct climate and agricultural managements to evaluate how soil biotic and abiotic properties regulate soil respiration and its resilience to simulated DRW cycles. We found that regardless of the DRW intensity, the effects of microbial community on soil respiration and its resilience to DRW cycles were dependent on soil type. Soil microbial communities yielded higher respiration rates and resilience in native than foreign soils under both one and four DRW cycles, supporting the "home-field advantage" hypothesis. Structural equation modeling demonstrated that soil pH and total C directly influenced soil respiration, but effects of soil abiotic properties on respiration resilience were mediated by microbial communities. Among microbial drivers, the microbial C utilization capacity (as characterized by community-level physiological profile, C-acquisition enzyme activities and microbial metabolic quotients) was the best predictor of respiration resilience to DRW cycles, followed by microbial biomass carbon/nitrogen ratio and microbial community composition. Our study suggests that soil microbial communities may have adapted to their historical conditions, which facilitates the resilience of soil respiration to changing environments, but this adaptation may accelerate C loss from soils facing increasingly variable climate.


Asunto(s)
Ecosistema , Suelo , Cambio Climático , Desecación , Sequías , Microbiología del Suelo
8.
Sci Total Environ ; 751: 141556, 2021 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-32882548

RESUMEN

Wetlands provide a wide range of ecosystem services, including supplying the food and shelter for a rich assemblage of waterbirds and providing the stopover sites that allow birds to make migratory journeys. Human impact and the ongoing climate change are however reducing the ability of wetlands to provide such important services. Through field surveys, GIS analyses and climate projections, we assessed the status of, and threats to, 38 largest wetlands belonging to the Mediterranean bird flyways in Sardinia and Sicily (Italy). We then combined ten decision criteria about avifaunal diversity and human/climate threats in order to prioritize the studied wetlands from most to least worthy of urgent interventions. Results showed that the main wetlands of these two regions have distinct demands with regard to the kind of actions required, going from the mitigation of tourism pressure to the prevention of climate-induced water shortage in summer. Furthermore, clear priorities for interventions emerged in both regions. Our study has direct implications for managers and researchers attempting to assess wetland conditions and set conservation priorities, thus offering a tool for deciding urgent interventions on the main stopover sites along the Mediterranean bird flyways.


Asunto(s)
Ecosistema , Humedales , Animales , Aves , Cambio Climático , Conservación de los Recursos Naturales , Humanos , Sicilia
9.
Sci Total Environ ; 751: 141481, 2021 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-32889453

RESUMEN

Drought is the most serious natural disaster causing severe damage to agriculture. Drought impacts on rice (Oryza sativa) production present a major threat to future global food security. In this paper, the Environmental Policy Integrated Climate (EPIC) model was used to simulate the growth of rice, in different periods (short-term (2019-2039), medium-term (2040-2069), long-term (2070-2099)), based on multiple Representative Concentration Pathways (RCP) scenarios. Drought intensity and rice physical vulnerability curves were assessed, based on the output parameters of EPIC, to evaluate global rice yield risk, due to drought. The results show that the average expected loss rate of global rice yield may reach 13.1% (±0.4%) in the future. The high-risk area of rice drought is mainly located in the north of 30°N. The fluctuation of rice drought risk and the proportion of increased risk areas will increase significantly. About 77.6% of the changes in rice drought risk are explained by variations in shortwave radiation (r = 0.88). Projections show that the average value of daily shortwave radiation increases by 1 W/m2 during the rice growth period, accompanied by an expected rice yield loss rate of about 12.7%. The rice drought risk methods presented in this paper provide plausible estimates of forecasting future drought risk under climate change, and address challenges of sparse data; we believe these methods can be applied to decisions for reducing drought-related crop losses and ensuring global food security.


Asunto(s)
Sequías , Oryza , Agricultura , Cambio Climático , Medición de Riesgo
10.
Sci Total Environ ; 751: 141763, 2021 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-32889471

RESUMEN

Anthropogenic climate change, namely climate alterations induced by human activities, is causing some issues to agricultural systems for their vulnerability to extreme events. Forecasts predict a global population increase in the near years that will exacerbate this situation, elevating the global demand for food. It will pose severe concerns in terms of natural resource usage and availability. Agriculture is one of the anthropogenic activities that will be more affected in the future. Climate extremes menace to affect the quantity and quality of crop production severely. Drought, water and soil salinity are considered among the most problematic factors that anthropogenic climate change will increase. This complex and worrying scenario requires the urgent implementation of sustainable measures which are capable of improving crop yield and quality, fostering the robustness and resilience of cropping systems. Among the more current methodology, the use of natural plant biostimulants (PBs) has been proposed to improve plant resistance to abiotic environmental stresses. The advantage of using these substances is due to their effectiveness in improving crop productivity and quality. Therefore, in this review, the most recent researches dealing with the use of natural PBs for improving plant resistance to drought and salinity, in an anthropogenic climate change scenario, have been reported and critically discussed.


Asunto(s)
Cambio Climático , Productos Agrícolas , Agricultura , Producción de Cultivos , Humanos , Suelo
11.
Sci Total Environ ; 751: 141779, 2021 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-32890800

RESUMEN

Climate change is a major world-wide challenge to livestock production because food security is likely to be compromised by increased heat stress of the animals. The objective of this study was to characterize, using bioclimatic indexes, two livestock regions located in an arid zone of México, and to use this information to predict the impact of global warming on animal production systems of these regions located in the state of Baja California (México). A 5-year database (i.e., 2011 to 2015) consisting of about one million data points from two zones (i.e., coast, valley) from four meteorological stations in the north of Baja California were used. Bioclimatic indexes were constructed for the four types of livestock production systems most common in this region, being: dairy cattle, beef cattle, sheep, pigs. The temperature-humidity index (THI) thresholds used to classify heat stress were determined and scaled for each livestock species as: THIbeef and THIpig 74 units; THImilk 72 units; and THIsheep 23 units. Statistical differences between indices were detected (P < 0.01) during summer for the valley and coast zones as (THIbeef = 72.9 and 51.8; THImilk = 80.6 and 67.4; THIpigs = 83.9 and 65.2; THIsheep = 29.5 and 20.1 units). Coast zone weather did not suggest vulnerability of livestock production systems to heat stress at any time of the year, but heat stress risk during summer for valley zone dairy cattle, sheep and pigs was classified as severe, but lower for feedlot cattle. Prediction models showed significant adjustment just in the coastal zone for THImilk, THIsheep, and THIsheep, suggesting more impact of global warming during summer in the coastal zone. Use of management strategies to reduce heat load of domestic animals during summer in northern Baja California is essential to maintain their productivity, with more emphasis in the valley zone.


Asunto(s)
Cambio Climático , Trastornos de Estrés por Calor , Animales , Bovinos , Trastornos de Estrés por Calor/veterinaria , Calor , Humedad , Ganado , México , Ovinos , Porcinos
12.
Sci Total Environ ; 753: 141985, 2021 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-32892000

RESUMEN

Global freshwater lakes are changing due to human activities and climate change. Unfortunately, sufficient long-term monitoring is lacking for most lakes. However, lake sedimentary archives can extend the instrumental record and reveal historical environmental trends. In particular, sedimentary DNA analysis of lacustrine sediment cores can aid the reconstruction of past trends in eukaryotic algal and cyanobacterial communities, as was conducted in this study for Lake Chaohu in China. The results presented here indicate that the construction of the Chaohu Dam in 1963 is associated with decreased richness of eukaryotic algal and cyanobacterial communities. Several groups, including the eukaryotic algal taxa, Chlorophyceae, and cyanobacterial groups like Dolichospermum, Microcystis, Planktothricoides, Cyanobium, Pseudanabaena, and Synechococcus, increased in abundance following inferred historical nutrient enrichment. Nutrient concentrations and hydrologic conditions were further implicated as the dominant controls on communities based on Random Forest and generalized additive modeling statistical analyses. In particular, significant increases in lake hydraulic residence times after the construction of the Chaohu Dam were significantly associated with altered biological community structures. Further, phosphorus enrichment was positively associated with increased richness and diversity of these communities following the 1980s. In addition, effects from increased atmospheric temperatures on eukaryotic algal and cyanobacterial communities were apparent. Here, high-throughput sequencing analysis of sedimentary DNA allowed the inference of long-term biodiversity dynamics of Lake Chaohu. These results underscore the important impacts of anthropogenic activities and climate change on aquatic ecosystems at the decadal scale.


Asunto(s)
Cambio Climático , Lagos , China , ADN , Ecosistema , Eucariontes , Eutrofización , Actividades Humanas , Humanos
13.
Sci Total Environ ; 752: 141794, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-32898800

RESUMEN

Covering large parts of Europe, Norway spruce (Picea abies L Karst.) plays an important role in the adaptation strategy of forest services to future climate change. Although dendroecology can provide valuable information on the past relationships between tree growth and climate, most previous studies were biased towards species-specific distribution limits, where old individuals grow slowly under extreme conditions. In the present study, we investigated the growth variability and climate sensitivity of 2851 Norway spruce trees along longitudinal (E 12-26°), latitudinal (N 45-51°), and elevation (118-1591 m a.s.l.) gradients in central-eastern Europe. We reveal that summer weather significantly affects the radial growth of spruce trees, but the effects strongly vary along biogeographical gradients. Extreme summer heatwaves in 2000 and 2003 reduced the growth rates by 10-35%, most pronounced in the southern Carpathians. In contrast to the population in the Czech Republic, climate warming induced a synchronous decline in the growth rates across biogeographical gradients in the Carpathian arc. By demonstrating the increased vulnerability of Norway spruce under warmer climate conditions, we recommended that the forest services and conservation managers replace or admix monocultures of this species with more drought-resilient mixtures including fir, beech and other broadleaved species.


Asunto(s)
Picea , Cambio Climático , República Checa , Europa (Continente) , Europa Oriental , Humanos , Noruega , Árboles
14.
Sci Total Environ ; 753: 141945, 2021 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-32911165

RESUMEN

Global climate change continues to cause alterations in environmental conditions which can be detrimental to aquatic ecosystem health. The development of pesticide resistance in organisms such as Hyalella azteca can lead to increased susceptibility to environmental change. This research provides a robust assessment of the effects of alterations in salinity on the fitness of H. azteca. Full-life cycle bioassays were conducted with non-resistant and pyrethroid-resistant H. azteca cultured under two salinity conditions representing a rise from freshwater control (0.2 psu) to increased salinity due to salt-water intrusion, reduced snowpack and evaporative enrichment (6.0 psu). Additionally, the upper thermal tolerance was defined for each population at each salinity. Pyrethroid-resistant H. azteca exhibited reduced thermal tolerance; however, they produced more offspring per female than non-resistant animals. Compared to the low salinity water, both non-resistant and pyrethroid-resistant H. azteca produced more offspring, grew larger (based on dry mass), and produced larger offspring in elevated salinity, although pyrethroid-resistant animals had lower survival and lipid levels. This study provides fundamental information about the fitness potential of H. azteca in a changing climate, suggesting advantages for non-resistant animals under future climate scenarios. In addition, this research further supports the need to consider the effects of global climate change when conducting risk assessment of contaminants of concern, as well as the contribution of contaminants when investigating climate change impacts on populations, as exposure may contribute to niche contraction.


Asunto(s)
Anfípodos , Insecticidas , Contaminantes Químicos del Agua , Animales , Cambio Climático , Ecosistema , Femenino , Insecticidas/análisis , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
15.
Mar Pollut Bull ; 160: 111660, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33181937

RESUMEN

The article presents the results from a research project investigating acoustic climate changes in the Gdansk Deep based on data extending from 1902 to 2019. This part of the southern Gotland Basin, is rarely discussed in the scientific literature. The speed of sound in the seawater is a function of temperature, salinity, and depth. In such shallow sea as Baltic Sea, the impact of depth is not substantial. The other two factors shape the hydroacoustic conditions. In the upper layer of seawater, the dominating factor is heat exchange at the water-atmosphere interface. The observed climate warming is reflected in the water temperature rise, which results in an increased speed of sound in the upper water layer. After years of sporadic salty inflows from the North Sea, the frequency of the phenomenon has increased since 2014. As a result, the salinity at the bottom exceeds values typical for that area.


Asunto(s)
Cambio Climático , Agua de Mar , Países Bálticos , Mar del Norte , Océanos y Mares , Sonido
16.
Mar Pollut Bull ; 160: 111661, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33181938

RESUMEN

An estimated 100 million people inhabit coastal areas at risk from flooding and erosion due to climate change. Seagrass meadows, like other coastal ecosystems, attenuate waves. Due to inconsistencies in how wave attenuation is measured results cannot be directly compared. We synthesised data from laboratory and field experiments of seagrass-wave attenuation by converting measurements to drag coefficients (CD). Drag coefficients varied from 0.02-5.12 with CD¯ = 0.74 for studies conducted in turbulent flow in non-storm conditions. A statistical model suggested that seagrass species affects CD although the exact mechanism remains unclear. A wave model using the estimated CD¯ as an input parameter demonstrated that wave attenuation increased with meadow length, shoot density, shoot width and canopy height. Findings can be used to estimate wave attenuation by seagrass, in any given set of conditions.


Asunto(s)
Cambio Climático , Ecosistema , Inundaciones , Humanos
19.
An Acad Bras Cienc ; 92(suppl 2): e20190058, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33146275

RESUMEN

Elevation creates a variety of physical conditions in a relatively short distance, which makes mountains suitable for studying the effects of climate change on biodiversity. We investigated the importance of climate and vegetation for the distribution of butterflies from 800 to 1400 m elevation. We sampled butterflies, and woody and rosette plants and measured air temperature and humidity, wind speed and gust, and solar radiation. We partitioned diversity to assess the processes underlying community shifts across altitudes - species loss versus replacement. We assessed the strength of the association among butterfly, vegetation, and climate. Butterfly richness and abundance decreased with altitude, and species composition changed along the elevation. Changes in butterfly composition with altitude were mainly through species replacement and by abundance increases in some species being compensated by decreases in others. Since the floristic diversity decreased with altitude due to soil conditions, and butterflies are closely related to their host plants, this could explain species replacement with altitude. Overall, we found a stronger association of butterfly community with vegetation than climate, but plant community and climate were also strongly associated between them. Butterfly richness was more strongly associated with plant richness than with temperature, while the reverse was true for butterfly abundance, which was more strongly associated with temperature than with plant richness. We must consider the complementary roles of resource and conditions in species distribution.


Asunto(s)
Mariposas Diurnas , Altitud , Animales , Biodiversidad , Cambio Climático , Ecosistema , Suelo
20.
Environ Monit Assess ; 192(11): 733, 2020 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-33123779

RESUMEN

Human-induced agricultural and developmental activities cause substantial alteration to the natural geography of a landscape; thereby accelerates the geologic soil erosion process. This necessitates quantification of catchment-scale soil erosion under both retrospective and future scenarios for efficient conservation of soil resources. Here, we present a revised universal soil loss equation (RUSLE) based soil erosion estimation framework at an unprecedentedly high spatial resolution (30 × 30 m) to quantify the average annual soil loss and sediment yield from an agriculture-dominated river basin. The input parameters were derived by using the observed rainfall data, soil characteristics (soil texture, hydraulic conductivity, organic matter content), and topographic characteristics (slope length and percent slope) derived from digital elevation model (DEM) and satellite imageries. The developed approach was evaluated in the Brahmani River basin (BRB) of eastern India, wherein the different RUSLE inputs, viz., rainfall erosivity (R factor), soil erodibility (K factor), topographic (LS factor), crop cover (C factor), and management practice (P factor) factors have the magnitude of 1937 to 4867 MJ mm ha-1 h-1 year-1, 0.023 to 0.039 t h ha MJ-1 ha-1 mm-1, 0.03 to 74, 0.16 to 1, and 0 to 1, respectively. The estimated average annual soil loss over the BRB ranged from 0 to 319.55 t ha-1 year-1, and subsequent erosion categorization revealed that 54.2% of basin area comes under extreme soil erosion zones in the baseline period. Similarly, the sediment yield estimates varied in the range of 0.96 to 133.31 t ha-1 year-1, and 35.81% area were identified as high soil erosion potential zones. The extent of erosion under climate change scenario was assessed using the outputs of HadGEM2-ES climate model for the future time scales of 2030, 2050, 2070, and 2080 under the four representative concentration pathways (RCPs) 2.6, 4.5, 6.0, and 8.5. The severity of soil erosion under climate change is expected to have a mixed impact in the range of -25 to 25% than the baseline scenario. The outcomes of this study will serve as a valuable tool for decision-makers while implementing management policies over the BRB, and can be well extended to any global catchment-scale applications.


Asunto(s)
Cambio Climático , Suelo , Conservación de los Recursos Naturales , Monitoreo del Ambiente , Sistemas de Información Geográfica , India , Modelos Teóricos , Estudios Retrospectivos
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