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1.
Braz. j. biol ; 82: e238403, 2022. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1180733

RESUMEN

Abstract As a result of biodiversity and ecosystem service losses associated with biological invasions, there has been growing interest in basic and applied research on invasive species aiming to improve management strategies. Tradescantia zebrina is a herbaceous species increasingly reported as invasive in the understory of disturbed forest ecosystems. In this study, we assess the effect of spatial and seasonal variation on biological attributes of this species in the Atlantic Forest. To this end, we measured attributes of T. zebrina associated with plant growth and stress in the four seasons at the forest edge and in the forest interior of invaded sites in the Iguaçu National Park, Southern Brazil. The invasive plant had higher growth at the forest edge than in the forest interior and lower leaf asymmetry and herbivory in the winter than in the summer. Our findings suggest that the forest edge environment favours the growth of T. zebrina. This invasive species is highly competitive in the understory of semi-deciduous seasonal forests all over the year. Our study contributes to the management of T. zebrina by showing that the summer is the best season for controlling this species.


Resumo As perdas de biodiversidade e os seus serviços ecossistêmicos ocasionadas pelas invasões biológicas, têm despertado o interesse em pesquisas básicas e aplicadas sobre as espécies invasoras com o objetivo de buscar estratégias de manejo. Tradescantia zebrina é uma das herbáceas crescentemente relatadas como uma invasora no sub-bosque florestal de ecossistemas impactados. Neste estudo, nós estudamos o efeito da variação espacial e sazonal sobre atributos biológicos desta espécie na Floresta Atlântica. Assim, nós mensuramos atributos de T. zebrina associados com o crescimento vegetal e o estresse nas quatro estações do ano em borda e interior da floresta de locais invadidos no Parque Nacional do Iguaçu, Sul do Brasil. A planta invasora apresentou maior crescimento na borda florestal do que no interior. Adicionalmente, assimetria foliar e herbivoria obtidos no inverno foram menores quando comparados ao verão. Nossos achados sugerem que os ambientes de borda florestal favorecem o crescimento de T. zebrina. Esta espécie invasora é altamente competitiva no sub-bosque da Floresta Estacional Semidecídua durante o ano todo. Nosso estudo contribui com o manejo de T. zebrina mostrando que o verão é a melhor estação para o controle desta espécie.

2.
Braz. j. biol ; 82: e240126, 2022. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1249275

RESUMEN

Abstract Wood-boring beetles develop in live trees and dead wood, performing ecological services such as decomposition and regulation of forest resources. Species of the Cerambycidae family, widely distributed in the world, bore into the trunks of trees and dead wood in native and cultivated areas. The objective is to report the first host plant for Thoracibidion lineatocolle (Thomson, 1865) (Coleoptera: Cerambycidae) and a new host plant for Temnopis megacephala (Germar, 1824) (Coleoptera: Cerambycidae) in the Brazilian Atlantic Forest biome. Three logs, with one-meter-long by 20 cm in diameter, were cut from the trunk of a healthy Anadenanthera colubrina (Fabaceae) tree in October 2013 and tied in the understory at 1.5m high in the Rio Doce State Park, Minas Gerais State, Brazil. The logs, exposed in the forest, were each removed after 40, 80 and 120 days and stored individually in a cardboard box in the "Laboratório de Campo do Projeto de Ecologia de Longa Duração (PELD-CNPq)" in the Rio Doce State Park. A total of 94 individuals of T. lineatocolle and 228 of T. megacephala emerged from the A. colubrina logs. This is the first report of a host plant for T. lineatocolle and a new host plant for T. megacephala.


Resumo Besouros broqueadores se desenvolvem em árvores vivas e madeira morta, realizando serviços ecológicos como decomposição e regulação de recursos da floresta. Espécies da família Cerambycidae, amplamente distribuídas no mundo, perfuram o caule de árvores e madeira morta em áreas nativas e cultivadas. O objetivo é relatar a primeira planta hospedeira de Thoracibidion lineatocolle (Thomson, 1865) (Coleoptera: Cerambycidae) e uma nova planta hospedeira para Temnopis megacephala (Germar, 1824) (Coleoptera: Cerambycidae) no bioma da Mata Atlântica brasileira. Três toras, com um metro de comprimento por 20 cm de diâmetro, foram cortadas de uma árvore sadia de Anadenanthera colubrina (Fabaceae) em outubro de 2013 e amarradas no sub-bosque a 1,5m de altura no Parque Estadual do Rio Doce, estado de Minas Gerais, Brasil. As toras, expostas na floresta, foram removidas, cada uma, após 40, 80 e 120 dias e armazenadas, individualmente, em caixas de papelão no "Laboratório de Campo do Projeto de Ecologia de Longa Duração (PELD-CNPq)" no Parque Estadual do Rio Doce. Um total de 94 indivíduos de T. lineatocolle e 228 de T. megacephala emergiu das toras de A. colubrina. Esse é o primeiro registro de uma planta hospedeira para T. lineatocolle e o de uma nova planta hospedeira para T. megacephala.

3.
J Environ Manage ; 300: 113823, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34649318

RESUMEN

Forested wetland soils within the Piedmont and Coastal Plain physiographic provinces of Northern Virginia (NOVA) were investigated to determine the utility of a handheld colorimeter, the Nix Pro Color Sensor ("Nix"), for predicting carbon contents (TC) and stocks (TC stocks) from on-site color measurements. Both the color variables recorded with each Nix scan ("Nix color variables"; n = 15) and carbon contents significantly differed between sites, with redder soils (higher a and h) at Piedmont sites, and higher TC at sites with darker soils (lower values of L, or lightness; p < 0.05). Nix-carbon correlation analysis revealed strong relationships between L (lightness), X (a virtual spectral variable), R (additive red), and KK (black) and log-transformed TC (Ln[TC]; |r| = 0.70; p < 0.01 for all). Simple linear regressions were conducted to identify how well these four final Nix variables could predict soil carbon. Using all color measurements, about 50% of Ln(TC) variability could be explained by L, X, R, or KK (p < 0.01), yet with higher predictive power obtained for Coastal Plain soils (0.55 < R2 < 0.65; p < 0.01). Regression model strength was maximized between Ln(TC) and the four final Nix variables using simple linear regressions when color measurements observed at a specific depth were first averaged (0.66 < R2 < 0.70; p < 0.01). While further study is warranted to investigate Nix applicability within various soil settings, these results demonstrate potential for the Nix and its soil color measurements to assist with rapid field-based assessments of soil carbon in forested wetlands.


Asunto(s)
Suelo , Humedales , Carbono/análisis , Bosques , Virginia
4.
Epidemiol Mikrobiol Imunol ; 70(3): 189-198, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34641693

RESUMEN

Tick-borne encephalitis (TBE) is a febrile illness caused by tick-borne encephalitis virus (TBEV), frequently manifesting as inflammation of the central nervous system. TBEV is a typical arbovirus, i.e., belongs to a group of viruses transmitted by blood-sucking arthropods. Taxonomically, TBEV is a member of the genus Flavivirus, family Flaviviridae. The disease is endemic in North Eurasia, from western Europe to East Asia. The virus occurs in natural foci of the disease all over Czechia, where it is transmitted predominantly by the castor bean tick (Ixodes ricinus). This infection has a potential to cause significant long-term disability affecting the quality of the patients life. Vaccine is available; however, vaccination coverage in Czechia is still low (around 30% of the total population). Lately, attention has been focused on new possibilities for early diagnosis and specific treatment, which so far has only been symptomatic or empirical.


Asunto(s)
Virus de la Encefalitis Transmitidos por Garrapatas , Encefalitis Transmitida por Garrapatas , Ixodes , Animales , Sistema Nervioso Central , Encefalitis Transmitida por Garrapatas/diagnóstico , Encefalitis Transmitida por Garrapatas/epidemiología , Europa (Continente) , Humanos
5.
J Environ Sci (China) ; 110: 55-72, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34593195

RESUMEN

Jiaxing created a precedent using bypass riparian marshes to purify micro-polluted water sources in China. Pond-wetland complex with constructed root channel technology becomes a paradigm which can be analogized as "human-body wetland model" based on bionics or biomimetics. Heterogeneous plant-bed/ditch system with highly active land/water ecotone interfaces, especially meandering boundaries, breeds many biochemical reactions "living areas". Optimization of hydraulic regulation promotes redox environment alternations and wetland treatment efficiency. Here we reported a series of upgrades and performances in Guanjinggang wetland after the Shijiuyang prototype. Morphological reform of plant-bed/ditch system played a vital role. Spatially root channel zone was main force of wetland purification, and temporally the treatment effect was higher in low-temperature seasons indicating non-temperature dependent mechanisms worked. Water pollution comprehensive index improved steadily from IV to III, and comprehensive pollution load was reduced by ca. 40%-60%. Comprehensive evaluation function value further showed the gradients purification effect of the upgraded wetland. Ecological wetlands ameliorated source water quality, and reduced drinking water treatment reagents, thereby bringing about economic benefits. Through wetlands operation, people can see how the micro-polluted surface water becomes clear and clean, so promoting a significant social benefit. As a viable component of urban green space, wetlands could beautify regional eco-environment, freshen the air, increase urban ecological taste, and enhance the eco-environmental protection publicity. Thus, the multifunctional service values and indirect benefits are substantial. Jiaxing ecological wetlands provide a typical paradigm for water pollution remediation in developing countries and plays a leading role in technology engineering radiation effect.


Asunto(s)
Purificación del Agua , Humedales , Humanos , Ríos , Agua , Contaminación del Agua
6.
Environ Monit Assess ; 193(11): 710, 2021 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-34626241

RESUMEN

The knowledge on urban ecosystem dynamics is being increasingly felt due to unprecedented symptoms arising out of urbanization. This study is aimed to assess land use-land cover changes (LULCCs) around a wetland ecosystem using high spatial resolution CORONA and Google Basemap satellite imageries. The imageries were processed by digitizing land cover features at 1:3000 scale in ArcGIS 10.1. The imageries were classified into nine classes, and an estimation of accuracy was performed utilizing the Kappa coefficient and error matrices. The overall accuracy obtained was 94% for the 2017 dataset. The key findings indicated a loss of 23% in the wetland area from 1980 to 2017. While in the vicinity, a significant increase in green spaces (706.2%) and roads (89.4%) was observed. Morphometric analysis revealed that the wetland has lost a surface area of 10.2 ha from 1980 to 2017. The maximum length (Lmax) of the wetland was reduced by 722 m while the maximum width (Wmax) decreased by 78 m. Bathymetric analysis revealed that the wetland is shallow with a depth ranging from 10 to 174 cm. The Carlson's Trophic State Index (TSI) of wetland ranging from 74 to 87 indicates hyper-eutrophic waters. Overall, the loss of wetland area, together with the reduction in morphometric features, low depth, and higher trophic status speak of anthropogenic pressures that are compromising the ecological integrity of this wetland. Therefore, landscape planning and governance are of pivotal importance for the conservation and management of wetland ecosystems in this region.


Asunto(s)
Ecosistema , Humedales , Monitoreo del Ambiente , Imágenes Satelitales , Urbanización
7.
Sheng Wu Gong Cheng Xue Bao ; 37(9): 3276-3292, 2021 Sep 25.
Artículo en Chino | MEDLINE | ID: mdl-34622635

RESUMEN

Due to the special geographical location and the complex ecosystem types, plateau wetlands play important ecological roles in water supply, greenhouse gas regulation and biodiversity preservation. Napahai plateau wetland is a special wetland type with low latitude and high altitude, and its microbial diversity was rarely studied. The diversity of microbial communities in the Napahai plateau wetland was analyzed using metagenomics method. Among the microbes detected, 184 phyla, 3 262 genera and 24 260 species belong to the bacterial domain, 13 phyla and 32 genera belong to the archaeal domain, and 13 phyla and 47 genera belong to the fungal domain. Significant differences in species diversity between soil and water were observed. Acidobacteria, Proteobacteria and Actinobacteria were dominant phyla in soil, while Proteobacteria and Bacteroides were dominant phyla in water. Since the carbon and nitrogen metabolism genes were abundant, the pathways of carbon fixation and nitrogen metabolism were analyzed. Calvin cycle, reductive tricarboxylic acid cycle and 3-hydroxypropionic acid cycle were the main carbon fixation pathways, while Proteobacteria, Chloroflexi, and Crenarchaeota were the main carbon-fixing bacteria group. As for the nitrogen cycle, nitrogen fixation and dissimilatory nitrate reduction were dominant in water, while nitrification and denitrification were dominant in soil. Proteobacteria, Nitrospirae, Verrucomicrobia, Actinobacteria, Thaumarchaeota and Euryarchaeota contributed to the nitrogen cycle. The study on microbial diversity of Napahai plateau wetlands provides new knowledge for the comprehensive management and protection of wetland environment in China.


Asunto(s)
Carbono , Humedales , Ecosistema , Metagenómica , Nitrógeno , Microbiología del Suelo
8.
Braz J Biol ; 83: e243666, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34495145

RESUMEN

Brazil is the world's richest country in biodiversity, including mammal species. In the Brazilian Cerrado biome, mammalian diversity is vast, with about 251 species, 32 of them are endemic and 22 listed as threatened species. In this work, we investigated species diversity of medium- and large-sized mammals in the private protected area RPPN Pontal do Jaburu (RPPN-PJ) and its surroundings, which is a flooded area located in an important biological corridor in the Cerrado-Amazon ecotone zone, a priority area for biodiversity conservation in Brazil. We used camera-trapping, active search (night and day), and track survey during dry season (Apr - Aug 2016). We recorded 29 mammal species, being the Carnivora order the most representative with 11 species. Regarding threat status, 35.7% of the recorded species were listed as threatened in Brazil and 32.1% worldwide. We highlight the high relative frequency of threatened species records such as Tapirus terrestris, Panthera onca, Blastocerus dichotomus, Pteronura brasiliensis, Priodontes maximus, and other, as well as the presence of the newly described aquatic mammal species Inia araguaiaensis. We stress the importance of RPPN-PJ and its surroundings for mammal conservation, which include complex habitats (wetlands) located in an important ecotone zone.


Asunto(s)
Mamíferos , Humedales , Animales , Biodiversidad , Brasil , Conservación de los Recursos Naturales , Especies en Peligro de Extinción
9.
Environ Monit Assess ; 193(10): 636, 2021 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-34498140

RESUMEN

Some wetlands in the northern Great Plains support hundreds to thousands of late-stage tadpoles providing important sources of recruitment to the Wood Frog (Lithobates sylvaticus) population while many other wetlands produce none. Relationships between water quality and late-stage tadpole abundance were determined to identify the water quality parameters associated with tadpole abundance. Water samples were collected, and late-stage tadpole abundances were assessed once each year in late June for 12 years in 26 wetlands. Catch or abundance was the number of tadpoles captured in 30 min with a dip-net. The catch of tadpoles was variable both among wetlands and over the long-term for individual wetlands, and ranged from 0 to several hundred individuals. Wood Frog tadpoles were especially sensitive to sodium and chloride concentrations. At Cl concentrations less than 5 mg/L, occupancy for late-stage tadpoles was 84%, and declined by about 8% for each 5 mg/L increase in Cl to 40.1 mg/L Cl, the maximum concentration associated with the detection of tadpoles. Optimal water quality for late-stage Wood Frog tadpoles included low concentrations of Na [Formula: see text] = 8.1 mg/L), and Cl [Formula: see text] = 4.2 mg/L) relative to total dissolved solids and other ions, and high concentrations of phosphorus. In a landscape where ion concentrations in wetlands can range over 3 orders of magnitude, water quality analyses suggest that abundant Wood Frog tadpole populations occur in wetlands dominated by snow-melt runoff with its characteristic low ion concentrations. The present study highlights the importance to amphibian conservation of the water quality environment of tadpole habitat.


Asunto(s)
Monitoreo del Ambiente , Calidad del Agua , Animales , Humanos , Larva , Ranidae , Humedales
10.
Dis Aquat Organ ; 146: 41-52, 2021 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-34498609

RESUMEN

The traditional strategy for national surveillance of salmonid alphavirus (SAV) infection in Norwegian fish farms relies on a costly, time-consuming, and resource-demanding approach based on the monthly sampling of fish from all marine farms with salmonids. In order to develop an alternative surveillance method, a water filtration method was tested in parallel with the ongoing surveillance program at 7 Norwegian marine farm sites of Atlantic salmon Salmo salar L. with no current suspicion of SAV infection. During the period from May 2019 to January 2020, seawater samples were collected from the top layer water inside all net-pens at these 7 sites. The samples were concentrated for SAV by filtration through an MF-Millipore™ electronegative membrane filter, followed by rinsing with NucliSENS® Lysis Buffer, before RNA extraction and analysis by RT-qPCR. SAV was detected from seawater at an earlier stage compared to traditional sampling methods, at all sites where the fish tested positive for SAV. A significant negative relationship was observed at all sites between the SAV concentration found in seawater samples and the number of days until SAV was detected in the fish. This means that the fewer the SAV particles in the seawater, the more days it took until SAV was detected in the fish samples. Based on this, sampling of seawater every month for the surveillance of SAV has a great potential as an alternative method for early detection of SAV in Atlantic salmon farms.


Asunto(s)
Alphavirus , Enfermedades de los Peces , Salmo salar , Animales , Enfermedades de los Peces/diagnóstico , Explotaciones Pesqueras , Agua de Mar
11.
An Acad Bras Cienc ; 93(suppl 3): e20201159, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34468490

RESUMEN

This study analysed the mycobiota on exoskeleton debris of the crab Neohelice granulata collected from an alkaline salt marsh and assessed the in vitro enzyme ability of selected isolates at different temperatures and pH. Exoskeleton fragments were incubated in moist chambers on paper and on agar medium. Growth and enzyme ability of selected fungi were also evaluated in agar media with 0.5 % casein, 1% Tween®20, and Chitin-Azure® by the production of a halo/growth ratio. We identified 22 fungal species using both methods. Since the two isolation methods added information to one another, both ones are necessary to recover the cultivable mycobiota associated with the exoskeleton debris. All fungi showed greater levels of enzyme activity in alkaline than acid medium with Tween®20. The halo diameter on casein and chitin varied according to the fungal isolate and pH. Most fungi had a larger halo at 4°C than at the other temperatures tested. Clonostachys rosea showed the greatest activity in all media at 4ºC. We conclude that exoskeletons of the N. granulata are a source of fungi able to produce enzyme activities that show differences upon incubation conditions to which they are cultivated such as ones including specific temperatures and pH values.


Asunto(s)
Braquiuros , Dispositivo Exoesqueleto , Animales , Concentración de Iones de Hidrógeno , Hypocreales , Temperatura , Humedales
12.
Environ Monit Assess ; 193(10): 645, 2021 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-34514553

RESUMEN

Phragmites growth in a marsh watershed due to increased salinity has been a crucial issue across the world. The objective of this study was to investigate the salinity movement in the ungagged Mentor Marsh of Ohio, USA, where the salinity had increased due to a number of potential sources causing a decline in the native vegetation and leading to the increased invasive phragmites growth. In this study, we conducted a detailed bathymetric survey and established several monitoring stations to record hourly environmental data in Mentor Marsh. Since Mentor Marsh has a complex hydrologic characteristic, which interacts with Lake Erie due to the backwater effect, a hydrodynamic model, Environmental Fluid Dynamic Code (EFDC +), was developed to simulate the western Mentor Marsh wetland's salinity distribution. We evaluated the model performance by comparing water level, temperature, and salinity using statistical measures for a duration from December 2019 to March 2020. The model was calibrated using the measured time-series data of water temperatures, water levels, and water salinity from monitoring stations in the western basin. The model performance for salinity calibration (R2 = 0.82, RMSE = 0.041, and Pbias = - 1.05%) and validation (R2 = 0.84, RMSE = 0.066, and Pbias = - 2.05%) was good. In the next step, the calibrated model was utilized to investigate the salinity distributions under different inflow and lake level rise conditions. Our analysis suggested that during high-flow conditions, the advection of the saline water from Marsh Creek was vigorous in comparison to the diffusion of salinity mixing by tidal influence pushing the salinity towards Mentor Marsh and resulting in the lower salinity distribution within the model domain. Similarly, when the lake level rise occurred, the model predicted a significant decrease in the salinity of Mentor Marsh near Lake Erie. The average decrease of salinity from the salinity during the base run was - 45.8% near Lake Erie, - 29.7% at the junction of Mentor Marina and Mentor Marsh, - 21.2% in Mentor Marsh, and - 4.4% in Marsh Creek. The analysis further suggested that under high-flow conditions from Marsh Creek, the salinity moved towards Mentor Marsh, especially when lake level rise conditions were considered. This is mainly because the high water level of Lake Erie pushed March Creek towards Mentor Marsh. However, the salinity moved towards Lake Erie from Marsh Creek during low-flow conditions. Presumably, the phragmites growth in the western section seems to be due to the road salt used in winter for deicing purposes.


Asunto(s)
Salinidad , Humedales , Monitoreo del Ambiente , Hidrología , Lagos
13.
Am J Bot ; 108(9): 1625-1634, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34542907

RESUMEN

PREMISE: Primates are important seed dispersers, especially for large-seeded (>1 cm long) tropical species in continuous and fragmented rainforests. METHODS: In three forest fragments within the Montes Azules Biosphere Reserve, southern Mexico, we investigated the effect of seed passage through the gut of howler monkeys (Alouatta pigra) on the germination rate and maximum germination (%) of native, large-seeded species. One group of howler monkeys, per fragment, was followed and fresh feces collected. Large seeds were removed to compare their germination success with non-ingested seeds of the same species collected underneath parent plants. RESULTS: Feces contained large seeds from seven tree species (Ampelocera hottlei, Castilla elastica, Dialium guianense, Garcinia intermedia, Pourouma bicolor, Spondias mombin, Trophis racemosa) and one liana species (Abuta panamensis). Except for G. intermedia, ingested seeds germinated significantly faster than non-ingested seeds, which had negligible germination. Ingested seeds of D. guianense, P. bicolor, S. mombin, T. racemosa, and A. panamensis had significantly greater germination, while G. intermedia had significantly lower germination and seed ingestion had no apparent effect for A. hottlei and C. elastica. CONCLUSIONS: In general, seed ingestion by howler monkeys confers faster germination compared with non-ingested seeds. Faster germination reduces predation probabilities and increases seedling establishment in forest fragments. Primate dispersal services contribute to germination heterogeneity within plant populations of old-growth forest species and to their persistence in forest fragments.


Asunto(s)
Alouatta , Dispersión de Semillas , Animales , Conducta Alimentaria , Germinación , Bosque Lluvioso , Semillas
14.
BMC Genomics ; 22(1): 697, 2021 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-34579659

RESUMEN

BACKGROUND: Nitrogen (N) is one of the main factors limiting the wood yield in poplar cultivation. Understanding the molecular mechanism of N utilization could play a guiding role in improving the nitrogen use efficiency (NUE) of poplar. RESULTS: In this study, three N-efficient genotypes (A1-A3) and three N-inefficient genotypes (C1-C3) of Populus deltoides were cultured under low N stress (5 µM NH4NO3) and normal N supply (750 µM NH4NO3). The dry matter mass, leaf morphology, and chlorophyll content of both genotypes decreased under N starvation. The low nitrogen adaptation coefficients of the leaves and stems biomass of group A were significantly higher than those of group C (p < 0.05). Interestingly, N starvation induced fine root growth in group A, but not in group C. Next, a detailed time-course analysis of enzyme activities and gene expression in leaves identified 2062 specifically differentially expressed genes (DEGs) in group A and 1118 in group C. Moreover, the sensitivity to N starvation of group A was weak, and DEGs related to hormone signal transduction and stimulus response played an important role in the low N response this group. Weighted gene co-expression network analysis identified genes related to membranes, catalytic activity, enzymatic activity, and response to stresses that might be critical for poplar's adaption to N starvation and these genes participated in the negative regulation of various biological processes. Finally, ten influential hub genes and twelve transcription factors were identified in the response to N starvation. Among them, four hub genes were related to programmed cell death and the defense response, and PodelWRKY18, with high connectivity, was involved in plant signal transduction. The expression of hub genes increased gradually with the extension of low N stress time, and the expression changes in group A were more obvious than those in group C. CONCLUSIONS: Under N starvation, group A showed stronger adaptability and better NUE than group C in terms of morphology and physiology. The discovery of hub genes and transcription factors might provide new information for the analysis of the molecular mechanism of NUE and its improvement in poplar.


Asunto(s)
Populus , Células Clonales/metabolismo , Regulación de la Expresión Génica de las Plantas , Nitrógeno/metabolismo , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Populus/genética , Populus/metabolismo , Estrés Fisiológico/genética , Humedales
15.
J Environ Manage ; 300: 113799, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34560464

RESUMEN

Given that the social and economic sustainability of rural areas is highly based on the protection of natural resources, biodiversity and human health, simple-operated and cost-effective wastewater treatment systems, like artificial constructed wetlands (CWs), are widely proposed for minimizing the environmental and human impact of both water and soil pollution. Considering that the optimization of wastewater treatment processes is vital for the reduction of effluents toxic potential, there is imperative need to establish appropriate management strategies for ensuring CW performance and operational efficiency. To this end, the present study aimed to assess the operational efficiency of a horizontal free water surface CW (HFWS-CW) located in a world heritage area of Western Greece, via a twelve-month duration Toxicity Identification Evaluation (TIE)-like approach, including both chemical and biological tracking tools. Conventional chemical tracking, by means of pH, conductivity, total COD, and nitrogen-derived components, like nitrates and ammonia-nitrogen, were monthly recorded in both influents and effluents to monitor whether water quality standards are maintained, and to assess potent CW operational deficiencies occurring over time. In parallel, Whole Effluent Toxicity (WET) bioassays were thoroughly applied, using freshwater algae and higher plant species (producers), crustaceans and rotifers (consumers), as well as human lymphocytes (in terms of Cytokinesis Block Micronucleus assay) to evaluate the acute and short-term toxic and hazardous potential of both influents and effluents. The integrated analysis of abiotic (physicochemical parameters) and biotic (toxic endpoints) parameters, as well as the existence of "cause-effect" interrelations among them, revealed that CW operational deficiencies, mainly based on poorly removal rates, could undermine the risk posed by treated sewage. Those findings reinforce the usage of WET testing, thus giving rise to the importance of applying appropriate water management strategies and optimization actions, like oxygen enrichment of surface and bottom of HFWS-CW basins, expansion of the available land, the enhancement of bed depth and seasonal harvesting of plants, for ensuring sewage quality, in favor of water resources protection and sustainable growth in rural areas.


Asunto(s)
Purificación del Agua , Humedales , Humanos , Saneamiento , Eliminación de Residuos Líquidos , Aguas Residuales
16.
J Environ Manage ; 300: 113703, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34509818

RESUMEN

Wetland plants play a major role in the process of wastewater treatment in constructed wetlands (CWs). The inhibitory effect of salt stress on plants may reduce the performance of CWs. In this study, salicylic acid (SA) and/or calcium ion (Ca2+) were used for root pretreatment to alleviate the salt stress in Iris pseudacorus L. The results showed that root pretreatment with SA and/or Ca2+ improved the response of Iris pseudacorus L. to salinity by increasing growth, photosynthetic pigments, Pro content, enzymes activities and K+ content. In addition, SA and/or Ca2+ application in saline conditions decreased the relative conductivity and content of malondialdehyde. RNA-seq analysis showed the expression of hormone signaling genes, potassium ion transporter genes, oxidative stress genes and photosynthesis genes were up-regulated after pretreating with SA and CaCl2. In conclusion, the addition of SA and Ca2+ could improve the saline wastewater treatment efficiency of CWs by enhancing the salt tolerance of Iris pseudacorus L.


Asunto(s)
Iris (Planta) , Humedales , Cloruro de Calcio , Iris (Planta)/genética , Ácido Salicílico/farmacología , Tolerancia a la Sal/genética
17.
J Environ Manage ; 300: 113720, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34521007

RESUMEN

The pollutant removal efficiency of traditionally constructed wetlands (CWs) is often limited due to low interaction time between wastewater and the CW matrix (plants, microbes, and substrates). A zigzag-horizontal subsurface flow constructed wetland with effluent recirculation (Z-HSSF + ER) was developed to improve removal efficiency. Echinodorus cordifolius plants were used in this study. The efficiency of the systems was evaluated using eutrophic wastewater. The results showed that the developed systems exhibited the high removal efficiency of algal cells, PO43-, and NO3- (97%, 70%, and 100%, respectively), within 5 days. Algal cells were removed by the interception mechanism of gravel and zigzag baffles. PO43- and NO3- in the eutrophic wastewater was mainly removed by E. cordifolius including rhizobacteria and other microorganisms. The long flow pathway created by the installation of zigzag baffles combined with effluent recirculation provides high dissolved oxygen (DO) in the systems and increases the interaction time between wastewater and the CW matrix, thus improving the pollutant removal efficiency of CWs.


Asunto(s)
Alismataceae , Humedales , Plantas , Eliminación de Residuos Líquidos , Aguas Residuales
18.
J Environ Manage ; 299: 113672, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34488112

RESUMEN

The hillslope is an essential natural spatial gradient that influences hydrological processes by affecting water distribution, surface flow, soil erosion, and groundwater recharge. To date, few studies have addressed only the hydrological processes of tropical forest hillslopes. To reveal the effect of hillslope on soil hydrological functioning-including water distribution and exchange, infiltration capacity, and flow behaviour-we conducted 36 field infiltration and nine dye-tracer investigations of different hillslope locations in the natural rainforest of Xishuangbanna, southwest China. The soil physical properties-including soil noncapillary and total porosity, saturated water capacity, and field water capacity-decreased with decreasing elevation from hilltop to middle slope and the valley bottom. The water infiltration capacity-including the initial infiltration rate, saturated soil hydraulic conductivity, and average infiltration rate-decreased from the hilltop to the valley bottom. Preferential flow dominated soil water movement more in the upper locations than in the valley bottom. The infiltration capacity parameters and preferential flow were significantly correlated with soil water content, noncapillary and total porosity, root biomass, and termite holes. These results indicated that along with the soil physical properties, root systems, animal activity, cracks, and stones affected the soil infiltration capacity and preferential flow. Differences in the hydraulic processes of each hillslope position contributed to the redistribution, transportation, and storage of surface and belowground water, resulting in differing availabilities of soil water resources and utilisation by plants. The findings of this study can help understand eco-hydrological processes in the context of water resources management in tropical mountain ecosystems.


Asunto(s)
Ecosistema , Suelo , China , Bosque Lluvioso , Agua/análisis
19.
Water Sci Technol ; 84(6): 1428-1437, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34559077

RESUMEN

A constructed wetland (CW) is a low-cost, eco-friendly, easy-to-maintain, and widely applicable technology for treating various pollutants in the waste landfill leachate. This study determined the effects of the selection and compiling strategy of substrates used in CWs on the treatment performance of a synthetic leachate containing bisphenol A (BPA) as a representative recalcitrant pollutant. We operated five types of lab-scale vertical-flow CWs using only gravel (CW1), a sandwich of gravel with activated carbon (CW2) or brick crumbs (CW3), and two-stage hybrid CWs using gravel in one column and activated carbon (CW4) or brick crumbs (CW5) in another to treat synthetic leachate containing BPA in a 7-d sequential batch mode for 5 weeks. CWs using activated carbon (CW2 and CW4) effectively removed ammonium nitrogen (NH4-N) (99-100%), chemical oxygen demand (COD) (93-100%), and BPA (100%), indicating that the high adsorption capacity of activated carbon was the main mechanism involved in their removal. CW5 also exhibited higher pollutant removal efficiencies (NH4-N: 94-99%, COD: 89-98%, BPA: 89-100%) than single-column CWs (CW1 and CW3) (NH4-N: 76-100%, COD: 84-100%, BPA: 51-100%). This indicates the importance of the compiling strategy along with the selection of an appropriate substrate to improve the pollutant removal capability of CWs.


Asunto(s)
Contaminantes Químicos del Agua , Humedales , Compuestos de Bencidrilo , Nitrógeno/análisis , Fenoles , Eliminación de Residuos Líquidos , Aguas Residuales , Contaminantes Químicos del Agua/análisis
20.
Water Sci Technol ; 84(6): 1498-1508, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34559083

RESUMEN

This study aimed to measure and ecologically assess heavy metals, including As, Cr, Pb, Cd, and Ni in water and sediment samples taken from Gomishan, an international wetland located in Golestan, Iran. Four sampling stations were selected to cover all parts of the wetland. The analyses of the heavy metals were performed by ICP-MS. Based on the content of the heavy metals in the sediments, the values of risks for individual heavy metals, as Er, and for total heavy metals, as IR, were estimated. Igeo and EF also presented the soil quality in terms of accumulated contamination. The average content of the heavy metals in water was 23.12, 4.14, 10.04, 6.71, and 94.48 µg/L for As, Cd, Cr, Ni, and Pb, respectively. The heavy metal concentrations in sediments were decreased in the following order: Pb (2130 ppb) > As (655 ppb) > Cr (295 ppb) > Ni (148.8 ppb) > Cd (148.8 ppb). The potential risk values for individual heavy metals were in the low range, Er < 40, except for Cd, which mostly posed a moderate ecological risk. The values of EF and Igeo showed that the sediments sampled from the Gomishan wetland were minimally enriched and contaminated. As the Gomishan wetland has a moderate risk of heavy metal contamination, conservative and monitoring activities should be performed.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , China , Monitoreo del Ambiente , Sedimentos Geológicos , Irán , Metales Pesados/análisis , Medición de Riesgo , Agua , Contaminantes Químicos del Agua/análisis , Humedales
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