C/N Ratio

The co-digestion of biosolids and organic fraction of municipal solid waste was compared with the direct digestion of biosolids. Addition of organic fraction of municipal solid waste improved carbon-to-nitrogen (C/N) ratio from 8.10 to 17.68 or 20.55 in the feedstock, and led to a higher volatile fatty acid (VFA) concentration of about 1500 mg/L in the solution and a lower solution pH under 6 in the beginning 20-day during digestion. Although the total biogas yield increased by the mixed feedstock, the biogas yield peak was postponed for about 10 days and the maximum biogas yield rate was reduced. After digestion, over 30% of total solid (TS) and over 65% of volatile solid (VS) were removed. However, the COD concentration in the effluent was still higher than 2300 mg/L and needed further treatment before discharge.

Krajcar Bronić I 1 , Barešić J 1 , Horvatinčić N 1 , Sironić A 1 , Surić M 2 , Lončarić R 2 , Lončar N 2 , Faivre S 3 , Bakran-Petricioli T 4 , Bočić N 3 , Buzjak N 3 , Veverec I 5 1 Ruđer Bošković Institute, Zagreb, Croatia 2 Department of Geography, University of Zadar, Zadar, Croatia 3 Department of Geography, Faculty of Science, University of Zagreb, Zagreb, Croatia 4 Department of Biology, Faculty of Science, University of Zagreb, Zagreb, Croatia 5 Elementary School Jelkovec, Sesvete, Croatia

Our analyses of cathepsin H activity levels and protein forms in human colorectal cancers compared to matched control mucosa support the concept that altered proteinase expression patterns may reflect both cancer stage and site. Cathepsin H-specific activity was significantly increased in colorectal cancers compared to control mucosa (P = 0.003; n = 77). Highest specific activities and cancer/normal ratios (C/N) for activity were measured in Dukes' B and C stage carcinomas, cancers involved in local spread and invasion to lymph nodes. In contrast, cathepsin B and L activities analysed in the same paired extracts had been shown to be most frequently elevated in earlier stage carcinomas (Dukes' A and B), confirming that cathepsin H demonstrates a distinct pattern of expression during colorectal cancer progression. Although cathepsin H activities were most commonly elevated in Dukes' C cancers at all colon sites, both specific activity and C/N ratios were significantly high...

Estimates of decomposition rates of coarse woody debris (CWD) and fluxes of nutrients therein are essential components of C and nutrient budget models. In a 30-year field experiment, we periodically measured mass remaining and nutrient concentrations in log segments of pine, spruce and fir in natural, mature coniferous forests in Alberta, Canada. The predicted turnover times (t95; years) were 43-44 years for pine, 42-60 years for spruce and 38-46 years for fir. Extrapolating from best-fit models, we predict that decomposition of these logs would be complete within 50 -60 years. C:N declined for most of the decomposition period and ratios of the three species converged at <200 at 90% mass loss. Net release of N occurred only after logs had lost 90% of their original C, and C:N had declined to <200. C:P declined and converged at 500-1000 at 90% mass loss. There was no evidence of net P release from logs even at 90% mass loss. It may be possible to estimate the amounts of N and P that will be incorporated into decaying logs based on the extent to which their initial C:N differs from 200 and initial C:P differs from 500.

Five age series stands of Alnus nepalensis D. Don monocultures have been selected from the Pankhasari range of the Kalimpong forest division in the Eastern tlimalayas. Chemical soil properties such as organic carbon, total nitrogen, C:N ratio, available phosphorus and exchangeable cations (Ca +2 , K + and Na +) were analysed in all these different ages of plantation stands from the surface to 1 m deep profiles to find out the long term effect of A. nepalensis on the soil quality of these erosion vulnerable slopes. Organic carbon, available phosphorus and total nitrogen content per-hectare increased with increasing plantation stand age. Analysis of variance for nutrients showed significant variation in depth (total nitrogen, P < 0.001 ; organic carbon, P < 0.001 ; available phosphorus, P < 0.05; exchangeable Ca +2 , P < 0.01; and exchangeable K +, P < 0.01) and between plantation stands (organic carbon, P < 0.05; and available phosphorus P < 0.05). High value of total nitrogen content (34.97t ha -~ ) was obtained in 46 yr old stand. Soil pH is low. It increased down the depth and in older plantations. These stands with high soil total nitrogen and organic carbon content show increased fertility of the stands. The cover of A. nepalensis in rocky, landslide and e:osion prone slopes of the Eastern Himalayas, serves to protect and improve soil quality.

Nitrous oxide (N2O) is a greenhouse gas formed during biological wastewater treatment under aerobic and anoxic conditions. Two reasons for high N2O emissions are low oxygen concentration during nitrification and low carbon/nitrogen-ratio during denitrification. In this full-scale study of N2O emissions from a sequencing batch reactor for treating digester supernatant, the oxygen concentration was reduced stepwise and the carbon/nitrogen-ratio was varied to investigate how N2O emissions were influenced. N2O concentrations were measured online in water and off-gas. A distinct relationship was found between low oxygen concentrations and high N2O emissions. N2O was formed in water during both nitrification and denitrification. Decreased oxygen concentration during nitrification led to increased nitrite concentration, which in turn led to increased N2O concentration in the subsequent denitrification phase. When nitrification resumed, accumulated N2O was stripped off to the atmosphere. A too low carbon/nitrogen-ratio resulted in increased N2O emissions in off-gas under longer-term conditions and increased risk of separate peak emissions. Very high N2O concentrations, over 76,000 ppm, were measured in the off-gas. Furthermore, the maximum N2O emitted during one cycle represented 217.9% of the total nitrogen load (36.2% of total nitrogen present in the bulk liquid at cycle start), among the highest emission levels measured from a full-scale municipal plant treating digester supernatant.

Nitrous oxide (N2O) is a greenhouse gas formed during biological wastewater treatment under aerobic and anoxic conditions. Two reasons for high N2O emissions are low oxygen concentration during nitrification and low carbon/nitrogen-ratio during denitrification. In this full-scale study of N2O emissions from a sequencing batch reactor for treating digester supernatant, the oxygen concentration was reduced stepwise and the carbon/nitrogen-ratio was varied to investigate how N2O emissions were influenced. N2O concentrations were measured online in water and off-gas. A distinct relationship was found between low oxygen concentrations and high N2O emissions. N2O was formed in water during both nitrification and denitrification. Decreased oxygen concentration during nitrification led to increased nitrite concentration, which in turn led to increased N2O concentration in the subsequent denitrification phase. When nitrification resumed, accumulated N2O was stripped off to the atmosphere. A ...

Agradeço a Deus por me conceder uma vida com saúde e estar próxima de pessoas queridas. Agradeço aos meus pais, Dinalva Franco da Silva e David Pires pela confiança, suporte e amor incondicional. Agradeço à minha irmã Suellem e sobrinhos Henrique e Amanda pelo carinho e compreensão nos momentos de minha ausência. Agradeço a todos amigos e colegas que estavam comigo durante a realização do mestrado, pela convivência e amizade, especialmente Alex Campanharo, Jéssica Dalazen e Juan Ricardo pelo auxílio na execução desta pesquisa, vocês foram essenciais. Agradeço ao Higor Moreira e seus familiares pelo apoio, carinho e compreensão durante esta jornada. Agradeço ao orientador Dr. Ademir Fontana pela orientação e por ter sido sempre presente, muito prestativo e atencioso no decorrer do curso de mestrado, contribuindo muito para minha formação profissional. Agradeço ao Prof. Dr. Fábio Luiz Partelli pela coorientação durante todo o planejamento, execução e escrita desta pesquisa científica. iii Agradeço aos funcionários da Fazenda Experimental Alex e Fabrício pelo suporte e auxilio no desenvolvimento das atividades, disponibilizando tempo, transporte e materiais necessários. Agradeço a todos os cafeicultores da região pela confiança e por nos receber tão bem em suas propriedades, compartilhando experiências e disponibilizando material para a pesquisa. Agradeço a empresa Embrapa Solos, no Rio de Janeiro e funcionários, em especial o Prof. Dr Wenceslau Teixeira pelo suporte e auxílio na execução das análises laboratoriais. Agradeço à Universidade Federal do Espírito Santo por conceder infraestrutura e equipamentos para o desenvolvimento do trabalho, além de funcionários bem preparados e atenciosos. Agradeço a CAPES pela concessão da bolsa, fator crucial para minha permanência no CEUNES/UFES.

The discovery of the Extreme Energy Cosmic Rays (EECR) with energy greater than 1020 eV has opened a new research branch of astrophysics on both observational and interpretative point of views. Together with the EECR one has also to consider the neutrino component which, independently on its primary or secondary origin, can reach comparable energies. These particles can be detected through the giant showers (EAS) produced in the Earth atmosphere and the induced fluorescent molecular nitrogen emission. Observing the EECR "signals" is very difficult; we need forefront technology or new developments. The main reason is that their flux is very weak, typically ofthe order ofa few events/year/l000 km2 per EECR of E 1020 eV. The proposed AirWatch mission, based on a single orbiting telescope which can measure both intensity and direction of the EAS, impose new concepts for the detectors: single photon sensitivity, fast response of the order of few microseconds with sampling times of tenths of nanoseconds, low noise and good S/N ratio, large area (linear dimension of the order of several tenths of cm), adaptability to a curved surface. Fortunately the spatial resolution requirements are somehow relaxed. The peculiar characteristics of this application are such that no available detectors satisfies completely the requirements. Therefore the fmal detector has to be the result of a R&D program dedicated to the specific problem. In this paper we survey a number of possible detectors and identify their characteristics versus the AirWatch mission requirements.

The major and trace element geochemistry of lavas erupted from four volcanic front (VF) stratovolcanoes in southeastern Guatemala show differences in the relative importance of flux and decompression melting in a continental arc setting. The VF stratovolcanoes exhibit a wide compositional range from basalt to dacite, although modern Pacaya erupts basaltic lavas. The VF basalts have relatively low MgO contents and plot outside the field of primary arc magmas defined by melting experiments on hydrous peridotite. After subtracting the effects of the fractionation, assimilation, and alteration of some VF lavas, separate partial melting and mixing trends were identified for Agua^Pacaya and Tecuamburro^Moyuta. The distinct chemical signatures of the hemipelagic and carbonate sediments subducted off Guatemala provide constraints on material transfer processes that occurred between the slab and mantle wedge. Model fluids and melts from the subducted slab were calculated using recently published mineral^aqueous fluid partition coefficients. Wide separation of the model fluid and melt compositions on a U/La versus Ba/Th diagram creates diagnostic mixing curves with an enriched mid-ocean ridge basalt source. Fluid from mature ocean crust has high U/La, fluid from carbonate sediment has high Ba/Th, and fluid and melt from hemipelagic sediments have both high U/La and Ba/Th. In a simple single-stage model, a mantle metasomatized by fluid originating largely from the oceanic crust with only minor sediment fluid contributions best explains the overall large ion lithophile element composition of the VF lavas. (Th/Rb) N ratios of V1 in the VF lavas from southeastern Guatemala require a component of sediment melting. Therefore, a more realistic two-stage model to describe the Guatemalan arc data involves an initial hemipelagic sediment melt input to the wedge followed by minor fluid additions from the oceanic crust or sediments. Correlation between measures of slab input and extent of melting in the older VF lavas from Tecuamburro and Moyuta favors flux-dominated melting near the base of the mantle wedge. In sharp contrast, the lack of a relationship between slab additions and melting in younger lavas from Agua and Pacaya volcanoes implies a significant role for decompression

A study was conducted using a bioenergetics approach to generate information on energy requirement and feed utilization of Litopenaeus stylirostris. Animals (initial mean weight 21 ± 1 g were fed ad libitum six experimental diets, ranging from 25 to 58% crude protein (CP), for 50 days. Weight gain increased from 21 to 30 g with increasing dietary protein level. Survival rates averaged 80%. Basal metabolism (HeE) and heat increment of feeding (HiE) were monitored using respirometry. HeE was on average 1 kJ shrimp -1 day -1 or 47 kJ kg live weight -1 day (22 kJ/kg 0.8 . d -1 ), slightly more than what is observed in fish. HiE averaged 0.2 kJ/shrimp -1 day -1 or 10 kJ kg live weight -1 day -1 (4 kJ/kg 0.8 d -1 ). It represented 31% and 12% digestible energy intake (DEI) for shrimp fed on 58% CP and 25% CP diet respectively. Non-fecal (UE + ZE) energy calculated on the basis of N-ammonia excretion averaged 0.2 μg N-ammonia/g dry wt./mn or 25 J live shrimp -1 day -1 in fasting stage and increased to 40 J in post-prandial stage. Ammonia production increased with increasing dietary crude protein (CP). The O:N ratio indicated that protein was increasingly used as an energy substrate as CP increased. The information was used to construct an energy budget for shrimp fed a protypical 40% CP diet. Gross energy intake (IE) was estimated at 6.5 kJ live shrimp -1 day -1 ; digestible energy intake (DEI) at 5, urinary and branchial excretion (UE + ZE) at 1.2, total heat production (HE) at 3.2; recovered energy (RE) at 0.6 (or 11% DEI). L. stylirostris adults issued from domesticated strain appeared to be more efficiently utilizing (i.e. converting into carcass energy) protein than carbohydrates. This preliminary energy budget can be used to construct theoretical feed requirement and waste outputs model for L. stylirostris.

Production of apple tends to decrease because of soil degradation. Objectives of this study are to determine the addition of compostAPT01 to increase fruit production in apple crop.This study aims to analyze the effect of the type and amount of compost APT01 as the soil organic matter to the apple crop production at 3 and 4 months of a day after defoliation and at harvest time (SR3, SR4 and SPN). The experiment was carried out according to completely randomized factorial design with the amount of compost APT01 and the season time of production. The experiment was conducted in 600 square meters. Organic materials of mud cake was fermented for 3 weeks. The amount of compost APT01 as much as 40, 60, and 80 kg per tree was applied a day after defoliation. A total of 27 apple trees aged about 10.0-10.5 years with a distance between trees 2-3 meters were randomly selected. Observations made during fruit growth 3 and 4 months after giving compost (SR3 and SR4) and at harvest (SPN). The parameters measured were the number and weight of fruit per tree. Results were analyzed variance, two-way ANOVA with interaction (α = 0.05), using Microsoft Excel. The addition of compost APT01 as much as 40, 60 and 80 kg per tree increasing the number and weight of fruit from initially 5.71 kg (58.84 fruits) to 9.99 kg (95.46 fruits) and 12.12 kg (104.06 fruits) respectively. Moreover, it also improves quality grade in terms of the average fruit produced from 9.56-10.22 fruits/kg (grade AB) to 8.59 fruits/kg (grade AA).

In coastal systems, the multiplicity of sources fueling the pool of particulate organic matter (POM) leads to divergent estimations of POM composition. Eleven systems (two littoral systems, eight embayments and semi-enclosed systems and one estuary) distributed along the three maritime façades of France were studied for two to eight years in order to quantify the relative contribution of organic matter sources to the surface-water POM pool in coastal systems. This study was based on carbon and nitrogen elemental and isotopic ratios, used for running mixing models. The POM of the estuary is dominated by terrestrial material (93% on average), whereas the POM of the other systems is dominated by phytoplankton (84% on average). Nevertheless, for the latter systems, the POM composition varies in space, with 1) systems where POM is highly composed of phytoplankton (≥ 93%), 2) systems characterized by a non-negligible contribution of benthic (8 to 19%) and/or riverine (7 to 19%) sources, and 3) the Mediterranean systems characterized by the contribution of diazotroph organisms (ca. 14%). A continent-to-ocean gradient of riverine and/or benthic POM contribution is observed. Finally, time series reveal 1) seasonal variations of POM composition, 2) differences in seasonality between systems, and 3) an inshore-offshore gradient of seasonality within each system that were sampled at several stations. Spatial and seasonal patterns of POM composition are mainly due to local to regional processes such as hydrodynamics and sedimentary hydrodynamic (e.g. resuspension processes, changes in river flows, wind patterns influencing along-shore currents) but also due to the geomorphology of the systems (depth of the water column, distance to the shore). Future studies investigating the link between these forcings and POM composition would help to better understand the dynamics of POM composition in coastal systems. ► Two littoral systems, eight embayments and one estuary were studied. ► Phytoplankton dominates POM in all systems except in the estuary (terrestrial POM) ► Mediterranean systems present a nonnegligible contribution of diazotroph organisms. ► POM composition and its seasonality undergo an inshore-offshore gradient. ► Hydrodynamics and geomorphology lightly drive the variability of POM composition.

Abstract—In this letter, we report metal nanocrystal (NC)-based Flash memory devices with single-layer (SL) and dual-layer (DL) Pt NCs as the storage element. The devices are fabricated using CMOS compatible process flow with optimized low-leakage high-k Al2O3 as the control dielectric. Large memory window (10 V for SL and 15 V for DL devices) is observed due to overerase, which increases the overall window. Improvement in DL memory window is found to be due to 1.5 times improvement in total stored charge over SL. Excellent high-temperature precycling retention is observed both for SL and DL devices. Index Terms—Dual layer (DL), flash memory, metal nano-crystal (NC). I.

In this letter, we report metal nanocrystal (NC)-based Flash memory devices with single-layer (SL) and dual-layer (DL) Pt NCs as the storage element. The devices are fabricated using CMOS compatible process flow with optimized low-leakage high-k Al 2 O 3 as the control dielectric. Large memory window (10 V for SL and 15 V for DL devices) is observed due to overerase, which increases the overall window. Improvement in DL memory window is found to be due to 1.5 times improvement in total stored charge over SL. Excellent high-temperature precycling retention is observed both for SL and DL devices.

The present study highlights a multi-objective optimization problem by applying utility concept coupled with Taguchi method through a case study in CNC end milling of UNS C34000 medium leaded brass. The study aimed at evaluating the best process environment which could simultaneously satisfy multiple requirements of surface quality. In view of the fact, the traditional Taguchi method cannot solve a multi-objective optimization problem; to overcome this limitation, utility theory has been coupled with Taguchi method. Depending on Taguchi's Lower-the-Better (LB) response criteria; individual surface quality characteristics has been transformed into corresponding utility values. Individual utility values have been aggregated finally to compute overall utility degree which serves as representative objective function for optimizing using Taguchi method. Utility theory has been adopted to convert a multi-response optimization problem into a single response optimization problem; in which overall utility degree serves as the representative single objective function for optimization. The study of combined utility theory and Taguchi method for predicting optimal setting. Based on Taguchi's Signal-to-Noise ratio (S/N), analysis has been made on the overall utility degree and optimal process environment has been selected finally which corresponds to highest S/N Ratio. Optimal result has been verified through confirmatory test. The case study indicates application feasibility of the aforesaid methodology proposed for multiresponse optimization and off-line control of multiple surface quality characteristics in CNC end milling.

The UVES Paranal Observatory Project (POP), is an ESO public database of about 400 stars whose high quality spectra were obtained with UVES, the high resolution spectrometer of the VLT. All stars were observed with two instrument modes, in order to cover almost completely the optical region (300-1000 nm). The resolving power is about 80 000, and for most of the spectra, the typical S/N ratio is 300-500 in the V band. Program stars fall into two groups, stars belonging to open clusters IC 2391 and NGC 6475, and bright field stars. For field stars, the only selection criterion applied was to cover the largest possible variety of spectral types in the HR diagram, including peculiar objects, e.g., Ap and Bp stars, Wolf-Rayet stars, Be stars, carbon stars and metal poor stars. The spectra have been reduced, coadded and merged and various products can be downloaded from a public area. For each star the final spectrum may be displayed through a dedicated user-friendly Spectral Preview Interface. The database is accessible at

2 -Curso de Pós-Graduação em Geologia 3 -Pesquisadora PRODOC-CAPES-UFBA Resumo O Batólito Trondhjemítico Nordestina (BTN) é um corpo com 720 km 2 alongado segundo NS, situado na região centrosul do Núcleo Serrinha, leste do Estado de Bahia. A intrusão se situa na interface tectônica entre os terrenos gnaíssico-migmatíticos arqueanos e as unidades vulcanossedimentares paleoproterozóicas do Greenstone Belt Rio ltapicuru. Dados de campo e estruturais mostram padrões de deformação típicos de interferência entre colocação plutônica e tectônica transpessional, provavelmente induzida pelo evento compressional NW-SE que conduziu ao fechamento da bacia do Itapicuru. Determinação geocronológica pelo método de evaporação Pb/Pb em monozircão forneceu idade de 2155±9 Ma para a colocação/cristalização do BTN. Dados geoquímicos, como conteúdos altos de Al 2 O 3 e baixos de Y e de Yb N , e altas razões de Sr/Y e (La/Yb) N , sugerem que o BTN resultou da fusão parcial de metabasalto, com granada e hornblenda no resíduo. Resultados isotópicos Sr e Nd mostram 0,7012 < 87 Sr/ 86 Sr inicial (2155) < 0,7016, 0,39 < ε Nd(2155) < 1,99) e idades modelos T DM em torno de 2,2 Ga. Estes resultados permitem interpretar as rochas do BTN como derivadas a partir da fusão parcial de uma fonte toleiítica paleoproterozóica com curta residência crustal.

The pH values in the profiles of unburnt (agricultural land) soils were found to increase as a function of soil depth and burning (400 to 1000℃) of the soils increased average pH by 8%. The average sand content of the burnt (soil around brick kilns) soil profiles was increased by 245%, while 39 and 36% decreased the silt and clay contents. Soil organic carbon (Corg) in the unburnt soils (0-20 cm) at different agro-ecological zones in the eastern region of Bangladesh ranged from 0.8 and 1.4%, whereas the content of microbial biomass carbon (Cmic) in the studied unburnt soils ranged between 5 and 7% of the total Corg, suggesting that the microbial biomass releasing considerable amounts of carbon in soil while burning of the soils drastically reduced this contribution to about 1%. The values of soil Cmic in the unburnt soils were approximately 2 to 6 times higher in the topsoils than the subsoils (20-60 cm). Variable rainfall, temperature and soil fertility had an overriding influence,...

A produção de café conilon em sistemas de manejo orgânico tem aumentado no estado do Espírito Santo, no entanto, informações sobre o impacto desse manejo nas características químicas do solo são poucas e inconclusivas.Objetivouse, neste trabalho, avaliar o efeito de manejos de adubação orgânica sobre atributos químicos de solo, em agroecossistema de café conilon. Em uma lavoura localizada no município de Linhares-ES, foi montado, experimento em delineamento de blocos casualizados com distribuição fatorial 2 x 2 x 5, com três repetições, sendo os fatores: dois compostos orgânicos; presença e ausência de leguminosa; e cinco proporções de cada composto (0; 25; 50; 75; e 100%) em substituição à adubação mineral recomendada. Cada repetição foi composta por uma parcela de 30 plantas de café, sendo 12 úteis centrais. Os compostos foram: composto 1, preparado com capim-elefante e palha-de-café na proporção 1:1 (v:v); e composto 2, preparado com capim-elefante, palha-de-café e cama-de-frango na proporção 2:1:1 (v:v:v). A leguminosa utilizada foi o feijão-de-porco, semeada nas entrelinhas dos cafeeiros. Com a utilização de 100% do composto 1 e composto 2, o pH atingiu valores de 6,5 e 6,3, respectivamente em relação ao pH 4,8, obtido com a adubação mineral. As médias obtidas para a soma de bases (SB) acompanharam o comportamento das bases trocáveis (Ca, Mg e K) do solo, ou seja, aumentaram de forma linear (p<0,10), com o aumento das proporções dos compostos. A adubação com compostos orgânicos é uma alternativa para melhorar a fertilidade do solo no agroecossistema de café conilon.

The use of chemical fertilizers for getting higher yield of crop imposes negative effects on soil properties. The application of organic amendments in combination with synthetic fertilizer to improve the growth of crop hence reduce its effect on soil has become imperative. A eld experiment was carried out at research farm of The University of Agriculture Peshawar, to study the effect of Humic acid (HA) and farmyard manure (FYM) along with chemical fertilizers on N, P, and K use e ciency and yield of wheat crop during rabi 2020-21. Humic acid and FYM was applied at the rate of 10 kg ha -1 and 10 tons ha -1 respectively while the source of nitrogen was applied at the rate of 90 kg ha -1 and 120 kg ha -1 , the source of phosphorous was applied at the rate of 60 kg ha -1 and 90 kg ha -1 and the source of potassium was applied at the rate of 45 kg ha -1 and 60 kg ha -1 . Treatments were arranged in randomized complete block design with three replications. Application of HA and FYM along with different levels of synthetic fertilizers signi cantly improved plant height, biological yield and 1000-grain weight as compared to control. The results indicated that the application of synthetic fertilizers alone signi cantly increased grain yield from 2535 kg ha -1 in control to 3495 kg ha -1 that was further improved to 3717 kg ha -1 when combined with HA and to 3949 kg ha -1 when applied with FYM. The combined application of FYM and HA with 75% NPK resulted in higher yield than 100% NPK suggesting fertilizers reduction with improvement in yield. Furthermore, the study assessed the total nutrient uptake and use e ciency, indicating that FYM and HA application with NPK fertilizer enhanced the uptake of N, P, and K by wheat plants. Notably, the highest nutrient use e ciency was recorded in plots treated with FYM and HA along with 75% NPK fertilizer. These ndings suggest the potential of integrated nutrient management practices to enhance wheat productivity and soil fertility.

The narrow-line Seyfert 1 galaxy IRAS 07598+6508 is known to be a stong Fe II emitter. The analysis of several high S/N ratio spectra shows that its spectrum is dominated by a relatively narrow "broad line" region (1780 km s -1 FWHM) emitting not only Fe II, but also Ti II and Cr II lines. Although we were unable to find a completely satisfactory physical model, we got the best agreement with the observations with collisional rather than radiative models, with a high density (n = 10 15 cm -3 ), a high column density (N H = 10 25 cm -2 ) and a microturbulence of 100 km s -1 . This BLR is qualitatively similar to the one observed in I Zw 1. We have not found traces in IRAS 07598+6508 of the narrow line regions found in I Zw 1.

Seasonal variations of proximate compositions, amino acids, and fatty acids contents of Monopterus cuchia were studied for the first time in Bangladesh. The fat and fatty acid, protein and amino acid contents showed a significant seasonal dependency. Lipid contents showed the wider variation than the protein contents. Among the 14 recorded amino acids, the primary amino acids were lysine, glutamic acid, arginine, glycine and aspartic acid. The ratio of essential and non-essential amino acids was higher in the post-monsoon season (0.69) than pre-monsoon (0.68) and monsoon season (0.68) and did not show seasonal discrepancies. The amount of fatty acids were found in order of saturated fatty acids (SFA) &gt; mono unsaturated fatty acids (MUFA) &gt; polyunsaturated fatty acids (PUFA). The predominant fatty acids were palmitic and stearic acids of SFAs, oleic and palmitoleic acid of MUFAs and linoleic and α linolenic acids of PUFAs group. The combined value of EPA+DHA varied from 1.44–5....

Fixed nitrogen is a limiting nutrient in most terrestrial ecosystems and has been assumed to be supplied almost entirely by freeliving bacteria as well as by bacteria living in association with plants. The survival and growth of many arthropods on diets with extremely high carbon to nitrogen (C:N) ratios suggest that these arthropods are not obtaining sufficient nitrogen from their diets but must be obtaining additional nitrogen from some other source(s). Estimates of N 2 fixation have suggested that symbiotic microbes of some arthropod hindguts could be obtaining this additional nitrogen as a result of nitrogen fixation. With the recent availability of antibody and nucleic acid probes, the presence of the enzyme that reduces dinitrogen gas to ammonia (nitrogenase) as well as the presence of its transcripts can be detected and localized with great sensitivity. A preliminary survey of a few detritivores indicates that nitrogen-fixing microbes of diverse forms are widespread in arthropod hindguts. In calculating nitrogen budgets, the possible contributions of nitrogen fixation by symbionts in arthropod guts, however, has been largely ignored. N 2 fixation in arthropod guts, with rates as high as 10-40 kg/ha/year being possible, may represent a significant contribution both to the growth of arthropods and to their ecosystem functions of processing carbon and nitrogen.

Microbial characteristics of soil are being evaluated increasingly as sensitive indicators of soil health because of the clear relationship between microbial diversity, soil and plant quality and ecosystem sustainability. This study aimed to determine microbial carbon biomass and microbial abundance after fire to estimate the degree of damage, including the rate of recovery of micro-organisms, in each area. The study also aimed to establish relationships between microbial biomass and microbial abundance and the physico-chemical properties of the soil. The study was conducted in three different study areas in Hiroshima prefecture, one unburned area and two burnt areas (one immediately after and one 2 years after fire). ANOVA showed a significant difference in microbial carbon biomass and microbial abundance among the study areas. Microbial carbon biomass and microbial abundance were highest in the unburned area, followed by the area burnt 2 years ago and lastly by the area studied immediately after fire. Carbon biomass was highly correlated with microbial abundance ( r 2 = 0.950). Carbon biomass and microbial abundance were shown to be significantly correlated to the soil's physico-chemical properties, such as pH, moisture content, water-holding capacity and carbon : nitrogen (C : N) ratio. However, the C : N ratio was closely correlated to both carbon biomass and microbial abundance with r 2 = 0.705 ( P < 0.01) and r 2 = 0.560 ( P < 0.01), respectively.

AbstractÐThe eect of hydraulic loading rate (HLR; 5 to 20 cm day À1 ) and carbon addition (1-6 g dried plant material per week) was determined at two temperatures (288C and 358C) in 18 ¯ow-through sediment-water wetland microcosms that were fed nitrate-contaminated water (30 mg N L À1 ). Nitrate removal eciencies varied from 8% to >95%, decreasing with increasing HLRs and increasing with increasing carbon addition rates. The eect of HLR and carbon addition rate were integrated into the C:N ratio, which alone was highly predictive of nitrate removal eciency. As nitrate removal eciencies increased, dissolved organic carbon in the euent also increased, as did chloroform formation potential. Nitrate-treatment wetlands may be a feasible method of remediating nitrate-contaminated groundwater.

The purpose of this study is to evaluate the main aspects of the mesoscale ocean circulation of the Brazilian Equatorial Margin using a ten-year hydrodynamic hindcast that successfully represented in situ and satellite observational data. The seasonality and distribution of the Amazon River Plume (ARP), as well as the volume transport of the North Brazil Current (NBC) in two cross-current sections were described. The results indicate the NBC influences on the shape and spread of the ARP, and the relationship between the seasonal behavior of the Inter-tropical Convergence Zone migration, of the wind stress curl, and of the northern branch of the South Equatorial Current with the NBC pattern.

In Central China, long-distance effects from collision between the North China and Yangtze cratons, uplift of the Tibetan Plateau and subduction of the Pacific Ocean are believed to converge in the Western Qinling. Mantle xenoliths from Baiguan and Haoti kamafugites in the Western Qinling were investigated to understand the lithospheric structure and mantle metasomatism beneath the orogenic belt. The Western Qinling lithosphere with depths of at least 120 km is geothermally hot and compositionally stratified, companied by a step-wise decrease in fertility with depth. The shallower portion of the lithospheric mantle is represented by type 2 xenoliths which lack alteration and deformation, and have fertile characteristics in compositions. The dominant rock type in the mantle section is the type 1 peridotites, which have had undergone relatively higher melt extraction and subsequent metasomatism. In-situ trace element data for minerals in the Baiguan and Haoti xenoliths are presented in this study. Baiguan clinopyroxenes have high LREE and show Ba, Th, U, Pb, Sr enrichment and negative Hf and Y anomalies, but the Haoti clinopyroxenes have large variations in trace elements and complicated distributions in LILE, and show negative Ti, Zr and Hf anomalies. Clinopyroxenes from both xenolith types have Ti/Eu and (La/Yb) N ratios in large ranges of 902-15,813 and 0-20, respectively. The petrological and geochemical characteristics suggest that the Western Qinling peridotites had been subjected to silicate and subsequent carbonatite metasomatism, and that carbonatite metasomatism was predominant in Baiguan but lesser in Haoti. Comparisons with the Western Qinling carbonatites and world-wide carbonatites indicate that carbonatite melts involved in the metasomatism originated from deep mantle and most likely related to carbonatite magma, with contributions from subducted oceanic crust. The type 2 peridotites, comprising clinopyroxene megacrysts and clinopyroxenite display similar trace element abundances and patterns, suggesting a close affinity in petrogenesis.

Iron isotopes, together with mineral elemental compositions of spinel peridotite xenoliths and clinopyroxenites from Hannuoba and Hebi Cenozoic alkaline basalts, were analyzed to investigate iron isotopic features of the lithospheric mantle beneath the North China Craton. The results show that the Hannuoba spinel peridotite xenoliths have small but distinguishable Fe isotopic variations. Overall variations in d 57 Fe are in a range of -0.25 to 0.14% for olivine, -0.17 to 0.17% for orthopyroxene, -0.21 to 0.27% for clinopyroxene, and -0.16 to 0.26% for spinel, respectively. Clinopyroxene has the heaviest iron isotopic ratio and olivine the lightest within individual sample. No clear linear relationships between the mineral pairs on ''d-d'' plot suggest that iron isotopes of mineral separates analyzed have been affected largely by some open system processes. The broadly negative correlations between mineral iron isotopes and metasomatic indexes such as spinel Cr#, (La/Yb) N ratios of clinopyroxenes suggest that iron isotopic variations in different minerals and peridotites were probably produced by mantle metasomatism. The Hebi phlogopite-bearing lherzolite, which is significantly modified by metasomatic events, appears to be much heavier isotopically than clinopyroxene-poor lherzolite. This study further confirms previous conclusions that the lithospheric mantle has distinguishable and heterogeneous iron isotopic variations at the xenoliths scale. Mantle metasomatism is the most likely cause for the iron isotope variations in mantle peridotites.

Anchovy oil is a very suitable supplementary ingredient for fish feeds due to the essential fatty acid composition. Almost all of anchovy oil produced in Turkey is used by aquatic/fish feed producers. In this research we determined fatty acids contents of anchovy oil produced in Turkey during the commercial catching season. The total saturated fatty acids (SFA) content of anchovy oil was determined as 32.33%, 31.65%, 31.59% in November, December and January, respectively. Within the saturated fraction, the major fatty acid was palmitic acid (C 16:0 ) with 18.74%, 18.27%, 18.20% ratios during the catching season. The monounsaturated fatty acids (MUFA) content ranged from 23.32% to 24.07%. Concerning the MUFA, oleic acid (C 18:1n-9 ) constituted the larger percentage than others. Docosahexaenoic acid (DHA) (C 22:6n3 ) and eicosapentaenoic acid (EPA) (C 20:5n3 ) contents of anchovy oil were found as average 15.64% and 9.39%, respectively. n-3 polyunsaturated fatty acids (PUFA) were higher than n-6 PUFA. Thrombogenicity (IT) and atherogenicity index (AI) values were 0.

Fifteen samples of stream sediments were collected from the Lesser Zab River (LZR), which represent one of three major tributaries of the Tigris River at northeastern Iraq. The sediment samples were subjected to laboratory studies including chemical analyses (using polarized energy dispersive XRF) for major (SiO

Submersible investigations along the East Rift segments, the Pito Deep and the Tercvaka transform fault of the Easter microplate eastern boundary, and on a thrust-fault area of the Nazca Plate collected a variety of basalts and dolerites. The volcanics consist essentially of depleted (N-MORB), transitional (T-MORB) and enriched (E-MORB) basalts with low (0.01-O. 1, < 0.7), intermediate (0.12-0.25,0.7-1.2) and high ( > 0.25, > 1.2-2) K/l? and (La/Sm), ratios, respectively. The Fe-Ti-rich ferrobasalt encountered among the N-MORBs are found on the Pito Deep Central volcano, on the Terevaka intra-transform ridge. on the ancient ( < 2.5 Ma) Easter microplate (called EMP, comprising the East Rift Inner pseudofaults and Pito Deep west walls) and on thrust-fault crusts. The most enriched (T-and E-MORB) volcanics occur along the East Rift at 25'50-27"s (called 26'5 East Rift) and on the Pito seamount located near the tip of the East Rift at 23"00'-23"4O'S (called 23"s East Rift). The diversity in incompatible element ratios of the basalts in relation to their structural setting suggests that the volcanics arc derived from a similar heterogenous mantle which underwent variable degrees of partial melting and magma mixing. In addition the Pito seamount volcanics have undergone less crystal fractionation ( < 20%) than the lavas from the other Easter microplate structures (up to 35-4595). The tectonic segmentation of the East Rift observed between 23 and 27"s corresponds to petrological discontinuities related to Mg# variations and mantle melting conditions. The highest Mg# (> 61) are found on topographic highs (2OBO-2300 m) and lower values (Mg# < 56) at the extremities of the East Rift segments (2500-5600 m depths). The deepest area (5600 m> along the East Rift is located at 23"s and coincides with a Central volcano constructed on the floor of the Pito Deep. Three major compositional variabilities of the volcanics are observed along the East Rift segments studied: (I) the 26"s East Rift segment where the volcanics have intermediate Na, (2.5-2,8%) and Fe, (X.5-11%) contents; (2) the 23"s East Rift segment (comprising Pito seamount and Pito Deep Central volcano) which shows the highest (2.9-3.4%) values of Na, and a low (8-g%) Fe, content; and (3) the 25"s (at 24"50'-26"lO'S) and the 24'S (at 24"10'-25"s) East Rift segments where most of the volcanics have low to intermediate Na, (2.6-2.08) and a high range of Fe, (g-13%) contents. When modeling mantle melting conditions, we observed a relative increase in the extent of partial melting and decreasing melting pressure. These localized trends are in * Corresponding author.

: Due to sub-THz millimeter wave (MMW) signals suffer substantial propagation loss in free-space or transmission line, and their inherent straight-line path of propagation affects connections and synchronization between the different parts of the communication system. A promising solution to overcome this problem is the millimeter wave over-fiber. The proposed research effort is to realize photonic-network compatible wireless data link at data rate up to 100 Gbit/s, and to explore a real-time MMW radar imaging system.

We present an application of the Fast Independent Component Analysis (FASTICA) method to the Cosmic Background Explorer Differential Microwave Radiometer (COBE-DMR) 4-yr data. Although the signal-to-noise (S/N) ratio in the COBE-DMR data is typically ∼1, the approach is able to extract the cosmic microwave background (CMB) signal with high confidence from high galactic latitude regions. However, the foreground emission components have too low a S/N ratio to be reconstructed by this method (moreover, the number of components which can be reconstructed is directly limited by the number of input channels). The reconstructed CMB map shows the expected frequency scaling of the CMB and, fitting for the rms quadrupole normalization Q rms-PS and primordial spectral index n we find results in excellent agreement with those derived from the minimum-noise combination of the 90and 53-GHz DMR channels without galactic emission correction. We extend the analysis by including additional channels (priors): the Haslam map of radio emission at 408 MHz and the Diffuse Infrared Background Experiment (DIRBE) 140-µm map of galactic infrared emission. The FASTICA algorithm is now able to both detect galactic foreground emission and separate it from the dominant CMB signal. Fitting again for Q rms-PS and n we find good agreement with the results of Górski et al. where galactic emission has been taken into account by means of correlation analysis of the DMR signal. We investigate the ability of FASTICA to evaluate the extent of foreground contamination in the COBE-DMR data further including an all-sky Hα survey to determine a reliable freefree. The derived frequency scalings of the recovered foregrounds are consistent with previous correlation studies. After subtraction of the thermal dust emission as in model 7 of Finkbeiner, Davis & Schlegel, we find a clear indication of an anomalous dust-correlated component which is the dominant foreground emission at 31.5 GHz and which is well fitted by a power-law spectral shape ν -β with β ∼ 2.5 in agreement with Banday et al.

We investigate the sedimentary record of Lago Thompson, a small lake (area 1.1 km2, watershed ∼8 km2) located at an elevation of 750 masl in Northern Chilean Patagonia (45.38 °S, 71.47°W). At Present, the climate conditions around the lake are relatively dry, with annual precipitation averaging 500 mm. The goal of this study is to evaluate the natural climate variability over the Last Millennium in Northern Chilean Patagonia and its impact on the environment. The coring site was selected after a bathymetric survey using an echo-sounder. Several short cores were retrieved in 2008 using an Uwitec gravity corer: the length of the cores ranges between 124 and 132 cm. The preliminary age model is based on 4 AMS radiocarbon ages measured on bulk sediment and organic macro-remains. The radiocarbon ages demonstrate that the sediment cores cover the last 850 to 950 years. This sediment record, which is characterized by accumulation rates ranging between 1 and 3 mm/yr, can therefore be studied at decennial to centennial resolution. To reconstruct past changes in climate and the environment, we conducted a multiproxy study combining sedimentological, mineralogical and geochemical analyses (LOI 105, 550 and 950°C, biogenic silica content, magnetic susceptibility, tephrostratigraphy, bulk organic geochemistry, bulk mineralogy by X-ray diffraction, and inorganic geochemistry by ITRAX core scanner and ICP-AES). Visual descriptions and X-ray radiographies demonstrate that the sediment record is relatively undisturbed. The sediment is composed of light brown organic-rich clayey material. The lower part of the core (below 75 cm) is finely laminated whereas the upper part is more homogeneous. Magnetic susceptibility values highlight two tephra layers that represent explosive eruptions of volcanoes from the southern volcanic zone of Chile (Hudson, Cay, or Macá volcanoes). The biogenic silica content of the sediment retrieved in Lago Thompson is high (40 to 80%), and probably related to the small catchment to lake surface ratio, which limits the supply of terrestrial particles to the lake. The inorganic content of the sediment is very low. Some clay minerals, quartz and feldspars were identified by X-ray diffraction. This observation is in agreement with the low C/N ratio (∼ 8-9) of the bulk organic matter, providing evidence that most of the organic particles originate from aquatic productivity. The high organic matter content (mean 15%, concentrations reaching up to 20%) and its low C/N ratio provide evidence that the lake productivity remained high over the last 900 years. Higher concentrations in biogenic silica and organic matter between 1550 and 1800 AD could be interpreted as drier climate conditions in the Andes of Northern Patagonia during the Little Ice Age. Further research will focus on biological proxies (diatom, chironomid, pollen) to improve this interpretation. This research is funded by Chilean and Belgian projects (Fondecyt project number 1070508, and FNRS "crédits au chercheur" 1360 2007-2010, respectively).

Seasonal variations of proximate compositions, amino acids, and fatty acids contents of Monopterus cuchia were studied for the first time in Bangladesh. The fat and fatty acid, protein and amino acid contents showed a significant seasonal dependency. Lipid contents showed the wider variation than the protein contents. Among the 14 recorded amino acids, the primary amino acids were lysine, glutamic acid, arginine, glycine and aspartic acid. The ratio of essential and non-essential amino acids was higher in the post-monsoon season (0.69) than pre-monsoon (0.68) and monsoon season (0.68) and did not show seasonal discrepancies. The amount of fatty acids were found in order of saturated fatty acids (SFA) &gt; mono unsaturated fatty acids (MUFA) &gt; polyunsaturated fatty acids (PUFA). The predominant fatty acids were palmitic and stearic acids of SFAs, oleic and palmitoleic acid of MUFAs and linoleic and α linolenic acids of PUFAs group. The combined value of EPA+DHA varied from 1.44–5....

The effect of various basal salts media, containing different nitrogen levels on in vitro adventitious shoot regeneration from leaf explants of 'Louise Bonne Panachee' and 'Seckel' pear (Pyrus communis L.) were investigated. Among the different basal salt formulae tested, Nitsch & Nitsch (1969) gave significantly better regeneration in most of the experiments. Shoot regeneration was altered with different NH4-N/NO3-N ratios. The best regeneration was obtained when NH4 :NO 3 was either 1:2 or 1' 3 regardless of overall N concentration. In addition, these data show that NH 4 was essential for adventitious shoot regeneration from pear leaf explants on White's (1943) medium.

Intensive agriculture (IA) is widespread in South Italy, although it requires frequent tillage, large amounts of fertilizers and irrigation water. We have assessed the efficacy of reversing IA to sustainable agriculture (SA) in recovering quality of a typical South Italy soil (Lithic Haploxeralf). This reversion, lasting from 2000 to 2007, replaced 75% of nutrients formerly supplied inorganically by farmyard manuring and reduced the tillage frequency. Several chemical and biochemical properties, functionally related to C and N mineralisation-immobilisation processes and to P and S nutrient cycles, were monitored annually from 2005 to 2007 in the spring. Reversing IA to SA decreased soil bulk density, almost doubled the soil organic matter (SOM) as favoured the immobilisation of C and N, increased most soil microbial indicators but decreased contents of nitrate, mineral N and K 2 SO 4 -extractable C. The K 2 SO 4 -extractable C/K 2 SO 4 -extractable organic N ratio suggested that substrate quality rather than the mass of readily available C and N affected biomass and activity of soil microflora. Also, the largely higher 10-day-evolved CO 2 -C-to-inorganic N ratio under SA than IA indicated that higher C mineralisation, associated with higher microbial biomass N immobilisation, occurred under SA than IA. Decreases in most soil enzyme activities under IA, compared to SA, were much higher than concomitant decreases in SOM content. Soil salinity and sodicity were always higher in IA than SA soil, although not critically high, likely due to the intensive inorganic fertilisation as irrigation waters were qualitatively and quantitatively the same between the two soils. Thus, we suggest that the cumulative small but long-term saline (osmotic) and sodic (dispersing) effects in IA soil decreased the microbial variables more than total organic C and increased soil bulk density.

Compost pit or natural composting is the common method of composting and the product as organic fertilizer is used as soil conditioner or fertilizer. Thus, this study focuses on the efficiency of different composting methods in terms of organic fertilizer produce, decomposition rate and economic viability. Combination of rice straws and sheep manure as substrates were used due to availability in the area. Four treatments employed and replicated four times. Treatment 1 is the natural composting, treatment 2 is the application of urea, treatment 3 is the application of indigenous microorganisms and treatment 4 is vermicomposting. Treatments were subjected in the analysis of variance using Randomized Complete Block Design. Comparison among means uses Least Significance Difference at 5% level. Results show that among four composting methods, application of IMO significantly produces organic fertilizer with 12.36 kilograms and higher decomposition rate of 61.81% among the other three com...

In terrestrial ecosystems, gross nitrogen mineralisation is positively correlated to microbial biomass but negatively to soil organic matter C-to-N ratios; the influence of the microbial community structure is less well known. Here, we relate rates of gross N mineralisation to fungi-to-bacteria ratios in three natural forest types of contrasting N availability and in a long-term N-loading experiment in a boreal forest. We report, for the first time, a strong negative correlation between gross N mineralisation and the fungi-to-bacteria ratio (R 2 adj =0.91, P=0.0005, N=7). There was also a negative correlation between gross N mineralisation and the C-to-N ratio (R 2 adj =0.89, P=0.001, N=7), but a weaker positive correlation between gross N mineralisation and soil pH (R 2 adj =0.64, P=0.019, N=7). Our analysis suggests that soil fungi-to-bacteria and C-to-N ratios are interrelated and that they exert strong influences on soil N cycling in boreal forests.

The net production of dissolved organic matter (DOM) and dissolved combined and free amino acids (DCAA and DFAA, respectively) by the hermatypic coral Acropora pulchra was measured in the submerged condition, and the production rates were normalized to the coral surface area, tissue biomass, and net photosynthetic rates by zooxanthellae. When normalized to the unit surface area, the production rates of dissolved organic carbon and nitrogen (DOC and DON, respectively) were 37 and 4.4 nmol cm -2 h -1 , respectively. Comparing with the photosynthetic rate by zooxanthellae, which was measured by 13 C-tracer accumulation in the soft tissue of the coral colony, the release rate of DOC corresponded to 5.4% of the daily net photosynthetic production. The tissue biomass of the coral colony was 178 µmol C cm -2 and 23 µmol N cm -2 , indicating that the release of DOC and DON accounted for 0.021% h -1 and 0.019% h -1 of the tissue C and N, respectively. The C:N ratios of the released DOM (average 8.4) were not significantly different from those of the soft tissue of the coral colonies (average 7.7). While DFAA did almost not accumulate in the incubated seawater, DCAA was considerably released by the coral colonies at the rate of 2.1 nmol cm -2 h -1 on average. Calculating C and N contents of the hydrolyzable DCAA, it was revealed that about 20% and 50%-60% of the released bulk DOC and DON, respectively, were composed of DCAA.

Soil fertility and leaching losses of nutrients were compared between a Fimic Anthrosol and a Xanthic Ferralsol from Central Amazônia. The Anthrosol was a relict soil from pre-Columbian settlements with high organic C containing large proportions of black carbon. It was further tested whether charcoal additions among other organic and inorganic applications could produce similarly fertile soils as these archaeological

Surficial sediment samples from seven shallow cross-shelf transects west of the Atchafalaya River in the northern Gulf of Mexico were analyzed during three sampling periods to determine the distribution of organic matter along the shelf and to evaluate the temporal variability of its deposition. Downcore sediment profiles from four sites, which represent 50-200 yr of deposition, were also examined to assess long-term changes in organic matter accumulation in this region. The Atchafalaya ''mud stream,'' which transports fine sediment westward parallel to the coastline, appears to play an important role in the transport of river-derived organic matter. In general, sedimentary organic carbon (%OC) and total nitrogen (%TN) decrease seaward within each transect and westward along the shelf. Atomic organic carbon : nitrogen (C/N) ratios indicative of a terrestrial source (>20) are observed near the mouth of the river during each sampling period, but values along the remainder of the shelf fall within a narrow range (9-11) with no apparent offshore trends. Depleted stable carbon isotope (d 13 C) values typical of C3 plant debris (À27%) are found near the river mouth and become more enriched (À22 to À21%) offshore. Organic matter distribution throughout much of the study area is similar during each sampling period, with significant seasonal differences close to the river mouth. Sediment, particulate organic carbon (POC), and particulate organic nitrogen (PON) budgets constructed for the study area reveal that 31% of the sediment exported by the Atchafalaya River is presently deposited within the study area annually, while the organic matter burial rates in the same region represent only 21% and 22% of the riverine POC and PON inputs, respectively. The POC and PON budgets also suggest that the organic matter remineralized in the water column is of algal origin (C/ N=7.2), whereas riverine organic matter (C/N=10) appears to be respired within the sediments. The 22.7 g POC m À2 yr À1 and 2.7 g PON m À2 yr À1 buried in the study area account for B5% of the combined riverine

Surficial sediment samples from seven shallow cross-shelf transects west of the Atchafalaya River in the northern Gulf of Mexico were analyzed during three sampling periods to determine the distribution of organic matter along the shelf and to evaluate the temporal variability of its deposition. Downcore sediment profiles from four sites, which represent 50-200 yr of deposition, were also examined to assess long-term changes in organic matter accumulation in this region. The Atchafalaya ''mud stream,'' which transports fine sediment westward parallel to the coastline, appears to play an important role in the transport of river-derived organic matter. In general, sedimentary organic carbon (%OC) and total nitrogen (%TN) decrease seaward within each transect and westward along the shelf. Atomic organic carbon : nitrogen (C/N) ratios indicative of a terrestrial source (>20) are observed near the mouth of the river during each sampling period, but values along the remainder of the shelf fall within a narrow range (9-11) with no apparent offshore trends. Depleted stable carbon isotope (d 13 C) values typical of C3 plant debris (À27%) are found near the river mouth and become more enriched (À22 to À21%) offshore. Organic matter distribution throughout much of the study area is similar during each sampling period, with significant seasonal differences close to the river mouth. Sediment, particulate organic carbon (POC), and particulate organic nitrogen (PON) budgets constructed for the study area reveal that 31% of the sediment exported by the Atchafalaya River is presently deposited within the study area annually, while the organic matter burial rates in the same region represent only 21% and 22% of the riverine POC and PON inputs, respectively. The POC and PON budgets also suggest that the organic matter remineralized in the water column is of algal origin (C/ N=7.2), whereas riverine organic matter (C/N=10) appears to be respired within the sediments. The 22.7 g POC m À2 yr À1 and 2.7 g PON m À2 yr À1 buried in the study area account for B5% of the combined riverine

Conidiation of an industrial strain of Penicillium (P.) camemberti, a ripening fungus, was examined on solid media. In order to evaluate the influence of nutritional factors on conidiation, we developed an inoculation and transfer procedure that allowed to obtain an homogenous mycelial biomass. Absence of conidiation was observed when ammonium sulphate and sodium nitrate were used as nitrogen sources. In contrast, conidiation increased significantly in the presence of ammonium phosphate or potassium nitrate with 4.8 Â 10 6 and 12 Â 10 6 spores ml À1 , respectively. By using those optimal conditions, the influence of nutrient starvation or calcium supply on conidiation was studied. Under the conditions tested, nitrogen starvation and calcium supply were better inducers than carbon starvation. A high carbon-to-nitrogen (C/N) ratio provided the highest level of with 4.2 Â 10 7 spores ml À1 and a sporulation index of 8.2 after 16 days of cultivation.

Root litter transformation is an important determinant of the carbon cycle in grassland ecosystems. Litter quality and rhizosphere activity are species-dependent factors which depend on the attributes of the dead and living roots respectively. These factors were tested, using non-disturbed soil monoliths of Dactylis glomerata L. and Lolium perenne L. monocultures. 13 C-labelled root litter from these monoliths was obtained from a first stand of each crop, cultivated under very δ 13 C-depleted atmospheric CO 2 (S1). In a factorial design, 13 C-labelled root litter of each species was submitted to a second, non 13 C-labelled, living stand of each species (S2). Carbon derived from S1 and from S2 was measured during an 18-month incubation in the root phytomass and in three particulate organic matter fractions (POM). The decay rate of each particle size fraction was fitted to the experimental data in a mechanistic model of litter transformation, whose outputs were mineralisation and stabilisation of the litter-C. Few differences were found between species, in the amount and biochemical composition of the initial root litter, but Dactylis roots showed a greater C:N ratio, a lower mean root diameter and a greater specific root length compared to Lolium. A transient accumulation of litter residues arose successively in POM fractions of decreasing particle size. The litter-continuum hypothesis was validated, i.e. that the attributes of the compartments (C:N, chemical composition and residence time) depended mainly on their particle size. The S1 species influenced the rate of litter decay while the S2 species controlled the efficiency of litter-C stabilisation versus mineralisation: Dactylis litter decomposed faster and Lolium rhizosphere allowed a greater proportion of litter C stabilisation. Discussions focus on the processes responsible of species strategy in relation with the morphological root traits, and the implication of strategy diversity for rich grassland communities.

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