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1.
Ecol Appl ; 31(6): e02394, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34164882

RESUMO

Seedling planting plays a key role in active forest restoration and regeneration of managed stands. Plant attributes at outplanting can determine tree seedling survival and consequently early success of forest plantations. Although many studies show that large seedlings of the same age within a species have higher survival than small ones, others report the opposite. This may be due to differences in environmental conditions at the planting site and in the inherent functional characteristics of species. Here, we conducted a global-scale meta-analysis to evaluate the effect of seedling size on early outplanting survival. Our meta-analysis covered 86 tree species and 142 planting locations distributed worldwide. We also assessed whether planting site aridity and key plant functional traits related to abiotic and biotic stress resistance and growth capacity, namely specific leaf area and wood density, modulate this effect. Planting large seedlings within a species consistently increases survival in forest plantations worldwide. Species' functional traits modulate the magnitude of the positive seedling size-outplanting survival relationship, showing contrasting effects due to aridity and between angiosperms and gymnosperms. For angiosperms planted in arid/semiarid sites and gymnosperms in subhumid/humid sites the magnitude of the positive effect of seedling size on survival was maximized in species with low specific leaf area and high wood density, characteristics linked to high stress resistance and slow growth. By contrast, high specific leaf area and low wood density maximized the positive effect of seedling size on survival for angiosperms planted in subhumid/humid sites. Results have key implications for implementing forest plantations globally, especially for adjusting nursery cultivation to species' functional characteristics and planting site aridity. Nursery cultivation should promote large seedlings, especially for stress sensitive angiosperms planted in humid sites and for stress-resistant species planted in dry sites.


Assuntos
Plântula , Clima Tropical , Florestas , Folhas de Planta , Árvores
2.
Int J Phytoremediation ; 22(10): 1068-1074, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32129081

RESUMO

Sludges, as biosolids, are organic soil amendments commonly used in assisted phytostabilitation. Extensive studies on their environmental impacts exists, particularly for improper land application and contents of trace elements, organic compounds and pathogens, but not for their content of cationic polyacrylamide polymers (C-PAMs). Direct toxicity of C-PAMs on aquatic organisms has been demonstrated but scarce information about plant toxicity is available. In this study, the effect of C-PAMs on early plant growth was evaluated by means of standard toxicity assays. Firstly, increasing doses of C-PAMs were applied as solutions to seeds of Avena sativa, Lactuca sativa and Solanum lycopersycum to evaluate germination and root elongation. Secondly, the effect of increasing doses of C-PAMs spiked in pig manure and mixed with sand (75 t ha-1 dry base) was evaluated on the emergence, radicle elongation and biomass of A. sativa. Results showed high phytotoxicity of C-PAMs in solutions above 1,000 mg L-1, but no effect was detected when spiked into experimental substrate; a significant effect was only observed above 5,000 mg L-1 for radicle elongation, aerial biomass, and radicle biomass. Results demonstrate direct phytotoxic effects of C-PAMs, which can be mitigated when spiked into an organic (pig manure) and mineral (sand) matrix.


Assuntos
Poluentes do Solo/análise , Solo , Resinas Acrílicas , Animais , Biodegradação Ambiental , Polímeros , Esgotos , Suínos
3.
Ambio ; 49(4): 986-999, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31364006

RESUMO

Ecotonal zones between eastern semi-arid steppes and Nothofagus spp. forests in western Patagonia are the result of broad ecosystem changes, which have intensified in the last 140 years. Our objectives were to determine historical changes in land use, land cover, and forces driving such changes in Nothofagus ecosystems in the Río Verde district in southern Chile, to support future management recommendations. This interdisciplinary study used historical records including scientific and military expeditions, Landsat imagery, and other archival sources. Forest cover changed radically between the late nineteenth and mid-twentieth centuries, from subsistence use by indigenous peoples, to forestry and livestock industries. The main driving forces of landscape change have been anthropogenic forest fires, logging, exotic pasture establishment, and mining. Future perspectives suggest that conserving the cultural values and natural resources of this region will depend on ecologically sound landscape planning, reversing forest fragmentation, restoring riparian corridors, and preserving indigenous archaeological sites.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Chile , Ecologia , Florestas , Árvores
4.
J Environ Qual ; 48(2): 430-438, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30951109

RESUMO

There is high demand for identifying socio-environmentally sound ways to dispose of large quantities of offensive odor-generating organic residues produced by intensive livestock farming. The use of these residues as amendments at large-scale mine tailings storage facilities for in situ plant-based reclamation may be a useful alternative. We performed a greenhouse assay to evaluate effectiveness of pig slurries and the solid organic fraction of aerobic-aerated pig slurries, both treated and not treated for odor emission, as amendments for copper tailings. Different doses of slurries or the solid organic fraction of the slurries, untreated and treated with either ozone or a commercial product used to manage strong odors (Just a Drop), were incorporated into tailings and stabilized (15 d) under greenhouse conditions. L. (ryegrass) was used as bioindicator for Cu and Zn toxicity. Plant performance (shoot and root dry biomass, Cu and Zn content in leaves) and general physicochemical characteristics of substrates were evaluated. Our results showed that odor management of pig residues was possible with commercial products, and their incorporation into tailings rapidly and effectively reduced odor emission. The solid organic fraction of the slurries neutralized acidic tailings, and both pig residues increased organic matter and nutrient content in tailings while reducing extractable Cu. As a result, ryegrass productivity was significantly improved by incorporation of either slurries or their solid organic fraction into tailings in a dose-dependent form. Foliar Cu content in ryegrass was not affected but foliar Zn content increased; however, Zn remained within acceptable ranges. Both the pig slurries and their soil organic fractions proved to be valuable residues for tailings reclamation.


Assuntos
Recuperação e Remediação Ambiental/métodos , Esterco , Mineração , Poluentes do Solo/química , Biodegradação Ambiental , Cobre
5.
J Environ Manage ; 230: 311-318, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30292019

RESUMO

The present study assesses the effect of tailing texture (loamy sand (LT) and sandy loam (ST)), dose of pig sludge (0, 50, 100 and 200 t ha-1) and amendment-contact time (14, 28 and 42 days) on physicochemical quality of amended substrate using Lolium perenne var Nui as a bioindicator. The main properties of LT differed of ST in levels of total organic carbon (0.19 and 0.58%), in pH (4.6 and 8.5), total Cu (202 and 1647 mg kg-1) and Zn content (31 and 137 mg kg-1). Soil pore water of experimental substrates was characterized for pH, electrical conductivity (EC) and Cu2+ ion activity (pCu2+) while ammonium nitrogen (NH4+-N), infiltration rate and general physicochemical characteristics were measured in substrates. Shoot biomass (SB), root biomass (RB) and the RB:SB ratio was calculated for L. perenne. The results showed there to be a significant interaction (p < 0.05) between tailing texture, sludge dose and amendment-contact time for pCu2+, infiltration rate, SB, RB, and RB: SB ratio, but not for pH, EC, or NH4+-N. However, sludge dose and amendment-contact time significantly affected all variables. By increasing dosages of pig sludge, pore water pH increased, and this was associated with decreases in pCu2+ and the infiltration rate. High doses of pig sludge (100 and 200 t ha-1) impaired growth of L. perenne irrespective of tailing texture and amendment-contact time, likely because of the rise of EC (up to 14 mS cm-1). For both tailing textures, the highest biomass was obtained after incorporation of 50 t ha-1 of pig sludge, with increasing values as amendment-contact time rose. In conclusion, effective management of pig sludge for tailing reclamation should guarantee doses <50 t ha-1 and amendment-contact time >28 days, irrespective of tailing texture.


Assuntos
Esgotos/química , Animais , Biomassa , Lolium/química , Nitrogênio/química , Solo/química , Suínos , Fatores de Tempo
6.
Environ Sci Pollut Res Int ; 24(15): 13484-13496, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28390018

RESUMO

Abandoned tailing dumps (ATDs) offer an opportunity to identify the main physicochemical filters that determine colonization of vegetation in solid mine wastes. The current study determined the soil physicochemical factors that explain the compositional variation of pioneer vegetal species on ATDs from surrounding areas in semiarid Mediterranean-climate type ecosystems of north-central Chile (Coquimbo Region). Geobotanical surveys-including physicochemical parameters of substrates (0-20 cm depth), plant richness, and coverage of plant species-were performed on 73 ATDs and surrounding areas. A total of 112 plant species were identified from which endemic/native species (67%) were more abundant than exotic species (33%) on ATDs. The distribution of sampling sites and plant species in canonical correspondence analysis (CCA) ordination diagrams indicated a gradual and progressive variation in species composition and abundance from surrounding areas to ATDs because of variations in total Cu concentration (1.3%) and the percentage of soil particles <2 µm (1.8%). According to the CCA, there were 10 plant species with greater abundance on sites with high total Cu concentrations and fine-textured substrates, which could be useful for developing plant-based stabilization programs of ATDs in semiarid Mediterranean-climate type ecosystems of north-central Chile.


Assuntos
Poluentes do Solo , Solo/química , Chile , Mineração , Plantas
7.
Environ Sci Pollut Res Int ; 21(6): 4665-74, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24352548

RESUMO

Long-term wastewater irrigation or solid waste disposal has resulted in the heavy metal contamination in both soil and groundwater. It is often separately implemented for remediation of contaminated soil or groundwater at a specific site. The main objective of this study was to demonstrate the hypothesis of simultaneous remediation of both heavy metal contaminated soil and groundwater by integrating the chemical immobilization and pump-and-treat methods. To accomplish the objective, three experiments were conducted, i.e., an incubation experiment was first conducted to determine how dairy-manure-derived biochar and phosphate rock tailing induced immobilization of Cd in the Cd-contaminated soils; second, a batch sorption experiment was carried out to determine whether the pre-amended contaminated soil still had the ability to retain Pb, Zn and Cd from aqueous solution. BCR sequential extraction as well as XRD and SEM analysis were conducted to explore the possible retention mechanism; and last, a laboratory-scale model test was undertaken by leaching the Pb, Zn, and Cd contaminated groundwater through the pre-amended contaminated soils to demonstrate how the heavy metals in both contaminated soil and groundwater were simultaneously retained and immobilized. The incubation experiment showed that the phosphate biochar were effective in immobilizing soil Cd with Cd concentration in TCLP (toxicity characteristics leaching procedure) extract reduced by 19.6 % and 13.7 %, respectively. The batch sorption experiment revealed that the pre-amended soil still had ability to retain Pb, Zn, and Cd from aqueous solution. The phosphate-induced metal retention was mainly due to the metal-phosphate precipitation, while both sorption and precipitation were responsible for the metal stabilization in the biochar amendment. The laboratory-scale test demonstrated that the soil amended with phosphate removed groundwater Pb, Zn, and Cd by 96.4 %, 44.6 %, and 49.2 %, respectively, and the soil amended with biochar removed groundwater Pb, Zn, and Cd by 97.4 %, 53.4 %, and 54.5 %, respectively. Meanwhile, the metals from both groundwater and soil itself were immobilized with the amendments, with the leachability of the three metals in the CaCl2 and TCLP extracts being reduced by up to 98.1 % and 62.7 %, respectively. Our results indicate that the integrated chemical immobilization and pump-and-treat method developed in this study provides a novel way for simultaneous remediation of both metal-contaminated soil and groundwater.


Assuntos
Carvão Vegetal/química , Recuperação e Remediação Ambiental/métodos , Água Subterrânea/química , Metais Pesados/química , Fosfatos/química , Poluentes do Solo/química , Poluentes Químicos da Água/química , Solo/química
8.
Br J Haematol ; 124(3): 329-35, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14717780

RESUMO

Budd-Chiari syndrome and portal vein thrombosis (BCS/PVT) are frequently associated with polycythaemia vera (PV). In an attempt to elucidate the mechanisms of BCS/PVT secondary to PV (T-PV), CD11b neutrophil expression, neutrophil oxidative burst and platelet-neutrophil complexes (PNC) were assessed in 17 such patients. Three groups served as controls: BCS/PVT not secondary to PV (T-nPV; n = 20), PV without thrombosis (PV-nT; n = 16), and healthy controls (HC; n = 20). Baseline CD11b expression (in mean fluorescence intensity units) was 101 [95% confidence interval (CI): 79-128] in T-PV patients, versus 25 (95% CI: 18-35) in T-nPV, 59 (95% CI: 43-80) in PV-nT, and 34 (95% CI: 25-48) in HC (P < 0.001). After N-formyl-L-methionyl-L-leucyl-L-phenylalanine activation, T-PV patients also showed higher CD11b values: 190 (95% CI: 151-238), versus 55 (95% CI: 41-72) in T-nPV, 111 (95% CI: 81-153) in PV-nT, and 77 (95% CI: 63-95) in HC (P < 0.001). In BCS/PVT, CD11b neutrophil expression had 90% specificity and 100% sensitivity for the association with PV. Finally, PV patients had higher oxidative burst and PNC than T-nPV patients or HC (P < 0.05). These results support a role for neutrophils in BCS/PVT secondary to PV and indicate that neutrophil CD11b expression could be of use for PV screening in BCS/PVT patients.


Assuntos
Síndrome de Budd-Chiari/imunologia , Antígeno CD11b/análise , Neutrófilos/imunologia , Policitemia Vera/imunologia , Adulto , Idoso , Análise de Variância , Biomarcadores/análise , Síndrome de Budd-Chiari/etiologia , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Policitemia Vera/complicações , Veia Porta , Curva ROC , Trombose Venosa/etiologia , Trombose Venosa/imunologia
9.
Rev. dent. Chile ; 81(2): 65-73, jun.-ago. 1990.
Artigo em Espanhol | LILACS | ID: lil-90057

RESUMO

Se desarrolla el concepto de disfunciones intracapsulares temporomandibulares, fundamentado en los conceptos de disfunción y patología funcional, enmarcándolas en una clasificación diagnóstica. Se profundiza desde un punto de vista etiopatogénico y de características clínicas, las diferentes clases de los cuadros denominados discrepancias discocondilares


Assuntos
Humanos , Deslocamento do Disco Intervertebral , Transtornos da Articulação Temporomandibular/patologia , Transtornos da Articulação Temporomandibular/classificação
10.
Rev. dent. Chile ; 80(2): 73-8, ago. 1989. ilus
Artigo em Espanhol | LILACS | ID: lil-80249

RESUMO

Entregado los fundamentos de osteoartritis temporomandibular, se procede a describir el enfoque terapéutico empleado en los casos de pacientes desdentados, para cumplir los objetivos de la eliminación de los procesos inflamatorios, el logro de posiciones de centricidad mandibular neuromuscular y la eliminación de los efectos traumatógenos de la ATM. Se destaca el empleo y procedimientos de uso de férulas oclusales y prótesis de trabajo que posibilitan la estabilizacion de las relaciones máxilo-mandibulares en áreas de centricidad al armonizar las posiciones de MIC (máxima intercuspidación) y PMC (posición muscular céntrica). Se describen los métodos de tratamiento y se enfatiza en las relaciones máxilo mandibulares neuromusculares como punto de partida para dar estabilidad definitiva a la rehabilitación oral correspondiente, describiendo el procedimiento para alcanzar tales logros


Assuntos
Adulto , Humanos , Masculino , Feminino , Oclusão Dentária Balanceada/normas , Contenções , Síndrome da Disfunção da Articulação Temporomandibular/fisiopatologia
11.
Rev. dent. Chile ; 80(2): 89-95, ago. 1989. ilus
Artigo em Espanhol | LILACS | ID: lil-80252

RESUMO

Se describe el esquema terapéutico específico para el tratamiento de subluxaciones discocondilares intermedias, enfatizándose los conceptos y fundamentos traumatológicos de reducción e inmovilización, previo a las etapas de rehabilitación funcional. Se presenta una técnica utilizada en un grupo de 14 pacientes con sus diagnósticos específicos fundamentales en aspectos clínicos y radiográficos, entre los cuales, las maniobras semiológicas para determinar juego articular temporomandibular como un factor importante de evaluación previo y postratamiento, en cuanto a la estabilidad articular se refiere


Assuntos
Humanos , Articulação Temporomandibular/lesões , Côndilo Mandibular/lesões , Luxações Articulares/terapia
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