Habitat structure,soil properties,and food availability do not predict terrestrial flatworms occurrence in Araucaria Forest sites     

Michelle Antunes  Ana Maria Leal-Zanchet  Carlos Roberto Fonseca 《Pedobiologia》2012,55(1):25-31

Flatworm community structure responds strongly to large-scale habitat alteration, with low diversity in disturbed environments. However, the ecological factors influencing small-scale distribution of flatworms are poorly understood. The aim of this study is to test if the occurrence of land planarians is influenced by microhabitat traits. The study was developed in two Araucaria Forest sites located in the São Francisco de Paula National Forest, southern Brazil. In each site, a 0.5 ha grid subdivided in 10 m² plots, was established. In 100 randomly selected plots, the occurrence and abundance of each land planarian species were recorded. For each plot, we also recorded information on six habitat structural traits, 21 soils properties, and 15 prey availability parameters. Sixty-six specimens were recorded, belonging to 21 species of land planarians. Although the two areas differed in relation to 17 ecological factors analyzed, mean flatworm density did not significantly differ between the two studied areas. The pattern of their abundance followed a Poisson distribution, suggesting that flatworms were randomly distributed throughout the study area. Simple logistic regressions and a multiple logistic regression, controlled for spatial autocorrelation, showed no evidence that the occurrence of terrestrial flatworms is controlled by habitat structure, prey availability or soil properties. In addition, a Principal Component Analysis, controlled for spatial autocorrelation, generated three main axes that represented 40.7% of the variation of the 42 ecological traits. This analysis showed very similar distribution of plots with and without flatworms along these three axes. The results suggest that land flatworms exhibit no pronounced microhabitat preferences inside undisturbed Araucaria Forest sites.  相似文献   

Kinetics and Adsorption Isotherms of Bisphenol A, Estrone, 17β-Estradiol, and 17α-Ethinylestradiol in Tropical Sediment Samples     

Bruno B. Cunha  Wander Gustavo Botero  Luciana Camargo Oliveira  Viviane M. Carlos  Marcelo L. M. Pompêo  Leonardo F. Fraceto  André H. Rosa 《Water, air, and soil pollution》2012,223(1):329-336

The sorption of four endocrine disruptors, bisphenol A (BPA), estrone (E1), 17β-estradiol (E2), and 17α-ethinylestradiol (EE2) in tropical sediment samples was studied in batch mode under different conditions of pH, time, and sediment amount. Data obtained from sorption experiments using the endocrine disruptors (EDs) and sediments containing different amounts of organic matter showed that there was a greater interaction between the EDs and organic matter (OM) present in the sediment, particularly at lower pH values. The pseudosecond order kinetics model successfully explained the interaction between the EDs and the sediment samples. The theoretical and experimentally obtained q _e values were similar, and k values were smaller for higher SOM contents. The k _F values, obtained from the Freundlich isotherms, varied in the ranges 4.2–7.4 × 10⁻² (higher OM sediment sample, S₂) and 1.7 × 10⁻³–3.1 × 10⁻² (lower OM sediment sample, S₁), the latter case indicating an interaction with the sediment that increased in the order: EE2 > > E2 > E1 > BPA. These results demonstrate that the availability of endocrine disruptors may be directly related to the presence of organic material in sediment samples. Studies of this kind provide an important means of understanding the mobility, transport, and/or reactivity of this type of emergent contaminant in aquatic systems.  相似文献   

Natural Biofilms in Freshwater Ecosystem: Indicators of the Presence of Polycyclic Aromatic Hydrocarbons     

Sandro Froehner  Karina Scurupa Machado  Luiz Fernando Dombroski  Anderson Correa Nunes  Regina Tiemy Kishi  Tobias Bleninger  Juan Sanez 《Water, air, and soil pollution》2012,223(7):3965-3973

Hydrophobic organic compounds are common in the environment, especially in water bodies like rivers and lakes. Generally, due to their physico-chemical characteristics, mainly to hydrophobicity, these compounds are adsorbed by suspended material or other compartments which provide compatibility. Thus, compounds such as polycyclic aromatic hydrocarbons (PAHs) are rapidly adsorbed onto suspended material or even naturally occurring biofilms in water bodies. Biofilms can be defined as complex structures with cells and aggregates of cells. The extracellular polymers present empty spaces that can be filled by water. The biofilm is a sessile microbial community with several kinds of organisms such as bacteria, protozoa, fungi, algae, and extracellular polymeric substances, which may be found on almost any surface exposed to water. Here, biofilms were used to monitor the presence of PAHs in the Barigui River in Curitiba, Brazil. For the measurements and collection of representative microcoenoses, a biofilm sampling device was designed consisting of six glass plates installed in an open polyvinyl chloride pipe of 30?cm diameter and 60?cm length. The sampling device was exposed in the Barigui River for 2?weeks campaigns. The formed biofilm was treated and chemical analysis was performed for PAHs determination. The results showed that biofilms can trap most of the PAHs, especially those with high K _ow values (octanol?Cwater partition coefficient). Four campaigns were conducted. The total PAHs concentration ranged from 11,204.34?±?560.12 to 45,846.90?±?2,290.45?ng/g. According to the isomers ratio, the main source of PAHs in the first and second campaign was of pyrolytic origin, in other words, the PAHs were by-products from burning of light-refined oil products (gasoline and diesel oil). Meanwhile, the other campaigns revealed that the main source is of petrogenic origin. However, the possibility of both sources is not discarded considering the scenario studied and the records of sediments samples. Most of the investigations carried out focused on the loading of river sediments and suspended solids, but the biofilms might detect the amount that could be taken up by benthic organisms, for instance.  相似文献   

Soil organic matter pools and carbon-protection mechanisms in aggregate classes influenced by surface liming in a no-till system     

Clever Briedis  João Carlos de Moraes Sá  Eduardo Fávero Caires  Jaqueline de Fátima Navarro  Thiago Massao Inagaki  Adriane Boer  Caio Quadros Neto  Ademir de Oliveira Ferreira  Lutécia Beatriz Canalli  Josiane Burkner dos Santos 《Geoderma》2012

The stabilisation of soil organic matter (SOM) is the result of the simultaneous action of three mechanisms: chemical stabilisation, biochemical stabilisation and physical protection. The objectives of this study were (i) to evaluate carbon-protection mechanisms in different SOM pools in soil aggregates and (ii) to identify the association of Ca^2 + with total organic carbon (TOC) under the influence of surface liming in a medium-textured Oxisol in a long-term experiment under no-till system (NTS) in southern Brazil (25° 10′ S, 50° 05′ W). The treatments consisted of application of zero or 6 tons ha^? 1 of dolomitic lime on the soil surface in 1993 and a reapplication of zero or 3 tons ha^? 1 of dolomitic lime in 2000 to plots with or without previous lime application. Soil samples collected at depths of 0–2.5, 2.5–5, 5–10 and 10–20 cm were separated into seven aggregate classes. In each of these classes, TOC, particulate organic carbon (POC) and mineral-associated organic carbon (MAOC) were analysed. The 8–19 mm sized aggregates from the 0–2.5 cm layer were assessed by energy-dispersive X-ray spectroscopy (EDS) for the elemental analysis of carbon (C) and calcium (Ca). The liming caused an accumulation of TOC in the aggregates, mainly at a depth of 0–2.5 cm. The aggregates from soils treated with lime had a higher mean weight diameter (MWD) that resulted in the accumulation of TOC, especially in the 8–19 mm aggregate class, that was linear and closely related with C input (R² = 0.99). The proportion of large aggregates in the treatments with lime was closely correlated with the TOC content of the whole sample. The largest dose of lime (9 tons ha^? 1) resulted in higher TOC, POC and MAOC values, mainly in the 8–19 mm aggregate class. The elemental analyses for C and Ca revealed similar spectra between them for the surface-liming treatments in the clay fraction found in the centres of the 8–19 mm aggregates. The surface application of lime to NT fields provided greater stability and protection of the intra-aggregate C, presumably due to Ca^2 + acting as a cationic bridge between OC and the kaolinite in the clay fraction.  相似文献   

Removal of Anionic Pollutants from Waters and Wastewaters and Materials Perspective for Their Selective Sorption     

Patrícia F. Lito  José P. S. Aniceto  Carlos M. Silva 《Water, air, and soil pollution》2012,223(9):6133-6155

The presence of some anionic species, such as nitrate, nitrite, chloride, sulfide, fluoride, and cyanide, in water supplies may represent a serious environmental problem. In this work, the main sources and harmful effects of their bioaccumulation on living organisms are reviewed, as well as the most adopted technologies for their uptake. The major advantages and disadvantages of each methodology are also listed. In general, ion-exchange has been elucidated as the most suitable removal process. In view of that the most promising materials used to remove anionic pollutants from aqueous solutions are highlighted in this review. In particular, the major efforts towards the development of low-cost and easily available effective sorbents for water decontamination are covered. For instance, natural waste solid materials and derivatives have emerged as promising low-cost exchangers for selective anions uptake. Besides, a number of structural modifications including the introduction of more suitable surface functional groups or compensation species into the sorbent matrix have been investigated in order to enhance sorbents selectivity and capacity for anionic pollutants. The influence of speciation and removal conditions is also focused.  相似文献   

Microbial Monitoring of the Recovery of Soil Quality During Heavy Metal Phytoremediation     

Gómez-Sagasti  María T.  Alkorta  Itziar  Becerril  José M.  Epelde  Lur  Anza  Mikel  Garbisu  Carlos 《Water, air, and soil pollution》2012,223(6):3249-3262

Soil pollution with heavy metals is a worldwide environmental problem. Phytoremediation through phytoextraction and phytostabilization appears to be a promising technology for the remediation of polluted soils. It is important to strongly emphasize that the ultimate goal of a heavy metal remediation process must be not only to remove the heavy metals from the soil (or instead to reduce their bioavailability and mobility) but also to restore soil quality. Soil quality is defined as the capacity of a given soil to perform its functions. Soil microbial properties are increasingly being used as biological indicators of soil quality due to their quick response, high sensitivity, and, above all, capacity to provide information that integrates many environmental factors. Indeed, microbial properties are among the most ecologically relevant indicators of soil quality. Consequently, microbial monitoring of the recovery of soil quality is often carried out during heavy metal phytoremediation processes. However, soil microbial properties are highly context dependent and difficult to interpret. For a better interpretation of microbial properties as indicators of soil quality, they may be grouped within categories of higher ecological relevance, such as soil functions, ecosystem health attributes, and ecosystem services.

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Mineralogical changes caused by grape production in a regosol from subtropical Brazilian climate     

Edson Campanhola Bortoluzzi  Diovane Freire Moterle  Danilo dos Santos Rheinheimer  Carlos Alberto Casali  George W. Melo  Gustavo Brunetto 《Journal of Soils and Sediments》2012,12(6):854-862

Purpose

Inadequate soil use and management practices promote commonly negative impacts on the soil constituents and their properties, with consequences to ecosystems. As the soil mineralogy can be permanently altered due to soil use, this approach can be used as a tool to monitor the anthropogenic pressure. The objective of the present study was to assess the mineralogical alterations of a Brazilian regosol used for grape production for 40?years in comparison with a soil under natural vegetation (forest), aiming to discuss anthropogenic pressure on soils.

Material and methods

Soil samples were collected at depths of 0?C0.20 and 0.20?C0.40?m from vineyard production and natural vegetation sites. Physical and chemical parameters were analysed by classic approaches. Mineralogical analyses were carried out on <2?mm, silt and clay fractions. Clay minerals were estimated by the relative percentage of peak surface area of the X-ray patterns.

Results and discussion

Grape production reduced the organic matter content by 28?% and the clay content by 23?% resulting in a decreasing cation exchange capacity. A similar clay fraction was observed in both soils, containing kaolinite, illite/mica and vermiculite with hydroxy-Al polymers interlayered. Neither gibbsite nor chlorite was found. However, in the soil under native vegetation, the proportion of illite (79?%) was higher than vermiculite (21?%). Whereas, in the soil used for grape production during 40?years, the formation of vermiculite was promoted.

Conclusions

Grape production alters the proportions of soil constituents of the regosol, reducing clay fraction and organic matter contents, as well as promoting changes in the soil clay minerals with the formation of vermiculite to the detriment of illite, which suggests weathering acceleration and susceptibility to anthropogenic pressure.

Recommendations and perspectives

Ecosystems in tropical and subtropical climates can be more easily and permanently altered due to anthropogenic pressure, mainly as a consequence of a great magnitude of phenomena such as temperature amplitude and rainfall that occurs in these regions. This is more worrying when soils are located on steep grades with a high anthropogenic pressure, like regosols in Southern Brazil. Thus, this study suggests that changes in soil mineralogy can be used as an important tool to assess anthropogenic pressure in ecosystems and that soil quality maintenance should be a priority in sensible landscapes to maintain the ecosystem quality.  相似文献   

Nitrogen supply associated with rhizobacteria in the first productive cycle of Marandu grass     

Sampaio  Fernando Antônio Rebouças  Teixeira Filho  Marcelo Carvalho Minhoto  da Silva Oliveira  Carlos Eduardo  Jalal  Arshad  Boleta  Eduardo Henrique Marcandalli  de Lima  Bruno Horschut  Rosa  Poliana Aparecida Leonel  Galindo  Fernando Shintate  de Souza  Jeferson Silva 《Journal of Crop Science and Biotechnology》2021,24(4):429-439

Journal of Crop Science and Biotechnology - The rhizobacteria of genus Azospirillum and Bacillus are effective at fixing atmospheric nitrogen, promote plant growth and can largely contribute to...  相似文献   

Marine Seagrass Extract of Thalassia testudinum Suppresses Colorectal Tumor Growth,Motility and Angiogenesis by Autophagic Stress and Immunogenic Cell Death Pathways     

Ivones Hernndez-Balmaseda  Idania Rodeiro Guerra  Ken Declerck  Jos Alfredo Herrera Isidrn  Claudina Prez-Novo  Guy Van Camp  Olivier De Wever  Kethia Gonzlez  Mayrel Labrada  Adriana Carr  Geovanni Dantas-Cassali  Diego Carlos dos Reis  Livan Delgado-Roche  Roberto Rafael Nuez  Ren Delgado-Hernndez  Miguel David Fernndez  Miriam T. Paz-Lopes  Wim Vanden Berghe 《Marine drugs》2021,19(2)

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Exploitation of Marine-Derived Robust Biological Molecules to Manage Inflammatory Bowel Disease     

Muhammad Bilal  Leonardo Vieira Nunes  Marco Thúlio Saviatto Duarte  Luiz Fernando Romanholo Ferreira  Renato Nery Soriano  Hafiz M. N. Iqbal 《Marine drugs》2021,19(4)

Naturally occurring biological entities with extractable and tunable structural and functional characteristics, along with therapeutic attributes, are of supreme interest for strengthening the twenty-first-century biomedical settings. Irrespective of ongoing technological and clinical advancement, traditional medicinal practices to address and manage inflammatory bowel disease (IBD) are inefficient and the effect of the administered therapeutic cues is limited. The reasonable immune response or invasion should also be circumvented for successful clinical translation of engineered cues as highly efficient and robust bioactive entities. In this context, research is underway worldwide, and researchers have redirected or regained their interests in valorizing the naturally occurring biological entities/resources, for example, algal biome so-called “treasure of untouched or underexploited sources”. Algal biome from the marine environment is an immense source of excellence that has also been demonstrated as a source of bioactive compounds with unique chemical, structural, and functional features. Moreover, the molecular modeling and synthesis of new drugs based on marine-derived therapeutic and biological cues can show greater efficacy and specificity for the therapeutics. Herein, an effort has been made to cover the existing literature gap on the exploitation of naturally occurring biological entities/resources to address and efficiently manage IBD. Following a brief background study, a focus was given to design characteristics, performance evaluation of engineered cues, and point-of-care IBD therapeutics of diverse bioactive compounds from the algal biome. Noteworthy potentialities of marine-derived biologically active compounds have also been spotlighted to underlying the impact role of bio-active elements with the related pathways. The current review is also focused on the applied standpoint and clinical translation of marine-derived bioactive compounds. Furthermore, a detailed overview of clinical applications and future perspectives are also given in this review.  相似文献