Influência da matéria orgânica e do ambiente no crescimento e acúmulo de solutos em Morinda citrifolia submetida à salinidade

O Noni (Morinda citrifolia L.) é uma planta tolerante aos efeitos salinos e alcalinos dos solos e desenvolve-se em regiões de clima seco ou úmido. Apesar da adaptabilidade intercontinental, ainda são poucas as informações sobre sua tolerância aos sais no solo brasileiro. Baseado no exposto, objetivou-se com o presente trabalho avaliar os efeitos da água salina no crescimento inicial do Noni. Para isso, foi conduzido um experimento em vasos de polietileno com capacidade para 20 L, em Sobral, Ceará. O delineamento estatístico adotado foi em blocos ao acaso, disposto no esquema de parcelas subsubdivididas, com 5 repetições. As parcelas foram constituídas pelos ambientes de cultivo (céu aberto e telado), as subparcelas pelos níveis de salinidade da água de irrigação (CEa: 0,3;1,5; 3,0; 4,5 e 6,0 dS m-1) e as subsubparcelas foram representadas pela ausência e presença de matéria orgânica. Aos 110 dias após a aplicação dos tratamentos (DAT), avaliaram-se: altura, massa seca da parte aérea (MSPA), da raiz (MSR), total (MST) e área foliar (AF), e aos 90 (DAT) os teores foliares de solutos orgânicos. Todas as variáveis de crescimento estudadas foram afetadas negativamente pela salinidade, sendo que o efeito observado a céu aberto foi mais expressivo do que no ambiente telado. A matéria orgânica não teve efeito atenuante sobre os efeitos deletérios da salinidade em plantas de noni. O acúmulo de prolina mostrou-se um sinalizador de dano causado pelo estresse, visto que os maiores acúmulos ocorreram nas plantas que sofreram maiores reduções no crescimento.

Dret internacional dels drets humans en períodes de crisi: criteris d"aplicació de les obligacions jurídiques internacionals en matèria de drets econòmics, socials i culturals

L"objecte de l"article és oferir una panoràmica dels criteris d"aplicació de les obligacions jurídiques internacionals en matèria de drets econòmics, socials i culturals (DESC) en períodes de crisi. L"estudi analitza les dificultats per considerar una crisi econòmica com una situació excepcional que amenaci la vida de la nació i permeti derogar o suspendre certs drets humans; també clarificar en quina mesura és possible derogar o suspendre els DESC. La pràctica internacional, judicial i quasi-judicial ens ofereix tres criteris potencialment restrictius de la discrecionalitat estatal per repercutir negativament en el gaudi dels DESC: existència d"obligacions mínimes, no regressivitat i protecció indirecta. El seu respecte podria evitar abusos com a resultat d"una crisi i garantir la progressivitat dels DESC, tot i que la relativitat de la justiciabilitat dels DESC afegeixi una dificultat legal estructural a nivell estatal.

Estudo da adsorção/dessorção do ácido 2,4 diclorofenoxiacético (2,4d) em solo na ausência e presença de matéria orgânica

The herbicides are being used in huge quantities for various porpouses. Once the herbicide finds its way into the environment, a major part of it comes in contact with soil. Humic substances are major organic constituents of soil. These substances may interact with herbicides in different modes and adsorption is probably the most important one. Adsorption will control the quantity of herbicide in the soil solution, and determines its persistence, leaching, mobility and bioavailability. In this work we studied the interaction between the herbicide 2,4D and soil in the presence and absence of organic matter. The methodology utilized for the determination of 2,4D was gas chromatography with eletron capture detector. The behavior of 2,4D was evaluated through Freundlich isotherms. It was verified that the herbicide 2,4D has a large adsorption in the humic acid .

Datação da fração humina da matéria orgânica do solo e sua comparação com idades 14C de carvões fósseis

The radiocarbon dating of the soil organic matter (SOM) is a polemic subject, due mainly to the complexity of the formation of the soils and to the variable contamination from several sources. Soil samples from 4 different Brazilian localities were submitted to physical and chemical pre-treatment for the extraction of humin fraction, which is the most stable organic compound and theoretically the oldest and representative of the age of the SOM. The radiocarbon dating obtained from the total SOM and their humin fractions are compared to the 14C ages from buried charcoals at similar depths. The radiocarbon ages obtained from such charcoals are, in most of the cases, concordant within the experimental errors of those obtained on humin fractions, or are in average 10% higher, with one exception. Thus, the ages on humin fractions could be assumed as the minimum ages for the associated soils, while the results obtained on total SOM, even at depths until 200 cm, exhibit pronounced contamination effect by modern carbon, rejuvenating their ages.

A indústria petroquímica no próximo século: como substituir o petróleo como matéria-prima?

The world reserves of petroleum will finish in about 100 years. For a tropical country like Brazil, biomass will be the natural substitute for petroleum. For the best utilization of biomass, it first needs to be separated into its principal components: cellulose, hemicelluloses, lignins, vegetable and essential oils, non-structural carbohydrates, bark and foliage. All feedstocks for the chemical industry can be obtained from these biomass components, as shown in the first part of this paper. In the second part we discuss how the major products from petrochemicals can be obtained from the different biomass components. We show that Brazil can use different strategies, compared to other countries, to obtain petrochemical products, which could result in innovations. However, it is necessary that the government starts to invest immediately in order to keep the petrochemical industries competitive with foreign industries, so that they continue to be one of Brazil's major employers.

Construção e otimização de um reator de baixo custo para a fotodegradação da matéria orgânica em águas naturais e sua aplicação no estudo da especiação do cobre por voltametria

This work describes the construction of a home-made low-cost reactor, using easily available materials, capable of destroying efficiently dissolved organic matter. Just 30 minutes of irradiation were sufficient to destroy more than 99% of the humic acids present in a solution of 4 mg C L-1. Copper speciation was evaluated in natural waters of different salinities to test the reactor's efficiency in destroying organically complexed metal species. The effect of the organic matter concentration, salinity, dissolved oxygen and temperature in the photo-oxidation process is discussed.

Caracterização de cinza de casca de arroz para uso como matéria-prima na fabricação de refratários de sílica

The characterization of rice husk ash, a deriving by-product of the burning of the rice husk during the rice processing is the object of this study. This by-product, for being rich in silica, can be an important raw material for the production of siliceous ceramics, such as thermal insulators and refractory. A combination of surface analysis, thermal analysis and microscopy analysis techniques was used for the characterization. The characterized by-product presented as main component the silica, under amorphous form, with a maximum content of alkalis around 1%, features that become it potentially interesting for the production of ceramic materials.

Influência da matéria orgânica na adsorção do fungicida triadimenol pelo solo

The adsorption of triadimenol (1-(4-chlorophenoxy)-3,3-dimethyl-1-(1H-1,2,4-triazol-1-yl)butan-2-ol) on soil samples with varying contents of organic matter was studied. The adsorption was described by means of the Freundlich's isoterm. An increase in the capacity of adsorption was observed as the content of organic carbon in the matrix increased. That effect was observed when removing the organic matter from the soil, when adding a urban waste compost to the soil sample as well as to the soil sample without organic matter, and also after leaving proportions of urban waste compost incubated in these matrices for a period of 120 days. The results show that the adsorption of the triadimenol in the soil is dependent of its content of organic carbon.

Extração de matéria orgânica aquática por abaixamento de temperatura: uma metodologia alternativa para manter a identidade da amostra

In this work was developed an alternative methodology to separation of aquatic organic matter (AOM) present in natural river waters. The process is based in temperature decreasing of the aqueous sample under controlled conditions that provoke the freezing of the sample and separation of the dark extract, not frozen and rich in organic matter. The results showed that speed of temperature decreasing exerts strongly influence in relative recovery of organic carbon, enrichment and time separation of the organic matter present in water samples. Elemental composition, infrared spectra and thermal analysis results showed that the alternative methodology is less aggressive possible in the attempt of maintaining the integrity of the sample.

Comentari a la setència sobre l'Estatut. Competència en matèria de consultes populars (art. 122)

L'article 122 de l'Estatut d'autonomia de Catalunya (EAC) reconeix a la Generalitat la competència exclusiva per a establir el règim jurídic, les modalitats, el procediment, l'acompliment i la convocatòria per la mateixa Generalitat o pels ens locals, en l'àmbit de llurs competències, d'enquestes, audiències públiques,formes de participació i qualsevol altre instrument de consultes populars, salvant el que disposa l'article 149.1.32 de la Constitució espanyola (CE). La STC 31/2010, de 20 de juny, avala al seu fonament jurídic 69, la constitucionalitat del precepte estatutari, però amb una interpretació marcadament restrictiva.

Control del pes per a les entrades/sortides de vehicles amb matèria primera

S'ha optat per la utilització de la tecnologia .NET per desenvolupar un projecte que s'instal·larà a tots els centres de producció del Grup Lecta, la funció més important del qual serà el control d'entrades/sortides i pesatge dels vehicles que abasteixen, principalment de matèria primera així com d'altres productes, a cadascuna de les fàbriques del grup.

Transformações químicas da matéria orgânica durante a compostagem de resíduos da indústria madeireira

Composting of sawdust and paper mill sludge, using a "Kneer" process reactor, was studied in an attempt to elaborate upon organic matter (OM) transformation during the process and to define parameters to measure the compost maturity level. Temperature, electron paramagnetic resonance (EPR) data, ash and C, H, N and S contents, and a spectroscopic method using ultraviolet-visible (UV-VIS) for alkaline (pH = 8.5) and solid samples was used to study the maturity of the compost samples. These parameters were measured in 6 humic acids (HA) extracted from the compost samples during 29 days. The results of this work show that the "Kneer" process is efficient in transforming ligno-celulitic residues in a short time (29 days), into an organic fertilizer material with application perspectives.

Anàlisi i propostes de prevenció del delicte mitjançant el disseny urbanístic en el municipi de Badia del Vallès

Aquest estudi analitza quatre zones del municipi català de Badia del Vallès, tres de les quals, d’acord amb les dades, constitueixen punts calents en matèria de delinqüència i incivisme (robatoris amb força en interior de domicili, robatoris en interior de vehicle i queixes veïnals per consum de drogues a la via pública i incivisme) i l’altre té gran importància estratègica, en tractar-se de la principal zona d’activitat comercial del municipi. La informació ha estat obtinguda a partir de quatre fonts: bases de dades policials, revisió de documents d’altres autors i institucions, entrevistes i observació participant. Posteriorment, s’ha comparat i sotmès a triangulació aquesta informació, i s’ha analitzat amb la perspectiva d’un marc teòric, amb l’objectiu d’establir un seguit de propostes d’intervenció urbanística adreçades,d’una banda, a la prevenció i a la disminució de la delinqüència als punts calents analitzats, però també a aconseguir una millor convivència. Entre les propostes d’intervenció hi ha la millora de l’enllumenat, la poda de l’arbrat que permeti el control informal, el manteniment i neteja dels espais i el mobiliari urbà, l’adequació dels espais i introducció d’equipaments,etc. Per últim s’ha definit una breu guia de recomanacions, aplicable a l’hora de dissenyar o recuperar espais públics, en la línea dels objectius esmentats: la prevenció i la reducció de la delinqüència i el foment de la convivència i el benestar de la població.

Distribuição de mercúrio em diferentes solos da Bacia do médio Rio Negro-AM: influência da matéria orgânica no ciclo biogeoquímico do mercúrio

Soils play an important role in the biogeochemical cycle of mercury as a sink for and source of this metallic species to atmospheric and hydrological compartments. In the study reported here, various types of soil were evaluated to ascertain the influence of parameters such as pH, organic matter content, Fe, Al, sand, silt, clay, C/H, C/N, C/O atomic ratios, and cation exchange capacity on the distribution of Hg in Amazonia's mid-Negro River basin. The data obtained were interpreted by multivariate exploratory analyses (hierarchical cluster analysis and principal component analysis), which indicated that organic matter plays an important role in mercury uptake in the various soils studied. The soils in floodable areas were found to contain 1.5 to 2.8-fold higher Hg concentrations than those in non-floodable areas. Since these soils are flooded almost year-round, they are less available to participate in redox processes at the soil/atmosphere interface. Hence, floodable areas, which comprise humic-rich soils, accumulate more mercury than non-floodable soils, thus playing an important role in the biogeochemical cycle of Hg in Amazonia's mid-Negro River basin.

Produção de matéria seca e de grãos por plantas de feijoeiro (Phaseolus vulgaris L.) cultivadas em solos tratados com metais pesados

This work aimed at evaluating the contents of extractable Cd, Pb, Zn and Cu with a solution of DTPA (diethyleneaminopentacetic acid) and to relate them with the production of dry material and grain production of bean plants under two conditions of experimentally contaminated soil materials with Cd, Pb, Cu and Zn: (i) samples of distrofic red latosol and (ii) humic yellow-red latosol. A decrease in the yield of dry matter was observed for all treatments, if compared with the zero-dose control sample; the grain yield was affected for the soil samples treated with Cd and Cu but only slightly for those treated with Pb and Zn.