Organic farming is expanding globally in response to the growing need for more sustainable food production. However, assessing both direct and indirect environmental effects is essential for identifying effective practices. This paper employs a Life Cycle Assessment (LCA) using a cradle-to-farm gate framework to evaluate the environmental effects of non-chemical weed control methods (row-cultivator, finger-weeding, flaming, and hand-weeding) in combination with four fertilization treatments (compost at 10, 30, and 60 m3 ha-1, and chemical fertilizer) in the production of four organic field crops grown under irrigated conditions in a Mediterranean climate. The analysis shows that producing 1 kg of crop results in emissions of 0.5-1.6 kg CO2 eq., 0.002-0.009 kg SO2, and energy use of 9-37 MJ. Over 95 % of these impacts are driven by irrigation, fertilizers, and weed and pest management. Significant differences between treatments underscore the role of crop-specific farming practices. Finger-weeding consistently lowered environmental impact across most conditions, whereas cultivation and flaming generally resulted in moderate to high impacts regardless of fertilizer level. Hand-weeding had the lowest environmental impact but was the most labor-intensive approach. The untreated control consistently led to the highest environmental burdens, reinforcing the necessity of effective weed management. By identifying key environmental hotspots, this study provides a foundation for optimizing weed control and fertilization strategies, integrating best farming practices, and informing policies to improve the sustainability and resilience of organic cropping systems in Mediterranean agriculture.

Rotary drums enable rapid composting compared to static systems. Residence times (RT) of 3-5 days are commonly applied to fulfill sanitary requirements and ensure the initial stabilization of organic matter. Practically, RT distribution (RTD) implies that a portion of the feed is discharged earlier than the mean RT, which may not guarantee safe application of the end product. This study assessed RTD and other physical-chemical and biological parameters of cattle manure and green waste composted in an Ecodrum (TM) rotary drum (similar to 10 m(3)). Two types of tracers were used: pieces of plastic tubing and lumps of raw material in which plant seeds were buried, which were packed in nylon socks. A transient-state during which less than 50 % of the drum volume was occupied was distinguished from a steady-state stage, during which the drum operated with its optimal loading of about two-thirds of its volume. Starting temperatures inside the drum were close to ambient when the drum was mostly empty and then increased up to 60-65 degree celsius as the occupied volume approached 50 %. The two types of tracers seemed to provide complementary measurements; under steady-state conditions, actual RTs were 60 % of the mean RT for 10 % of the feed material. The viability of plant seeds which were included in tracers was somewhat dependent on the specific RT. Under transient-state conditions, even shorter RTs (relative to the mean RT) are expected, coupled with non-thermophilic conditions, reducing the likelihood of adequate destruction of pathogens.

Organic amendment, and especially the use of composts, is a well-accepted sustainable agricultural practice. Compost increases soil carbon and microbial biomass, changes enzymatic activity, and enriches soil carbon and nitrogen stocks. However, relatively little is known about the immediate and long-term temporal dynamics of agricultural soil microbial communities following repeated compost applications. Our study was conducted at two field sites: Newe Ya’ar (NY, Mediterranean climate) and Gilat (G, semi-arid climate), both managed organically over 4 years under either conventional fertilization (0, zero compost) or three levels of compost amendment (20, 40 and 60 m 3 /ha or 2, 4, 6 L/m 2 ). Microbial community dynamics in the soils was examined by high-and low-time-resolution analyses. Annual community composition in compost-amended soils was significantly affected by compost amendment levels in G (first, second and third years) and in NY (third year). Repeated sampling at high resolution (9–10 times over 1 year) showed that at both sites, compost application initially induced a strong shift in microbial communities, lasting for up to 1 month, followed by a milder response. Compost application significantly elevated alpha diversity at both sites, but differed in the compost–dose correlation effect. We demonstrate higher abundance of taxa putatively involved in organic decomposition and characterized compost-related indicator taxa and a compost-derived core microbiome at both sites. Overall, this study describes temporal changes in the ecology of soil microbiomes in response to compost vs. conventional fertilization. Highlights Dose-dependent changes in soil microbiome structure by manure compost application Dynamic short-and long-term changes in soil microbiomes by compost amendment Climate, soil properties and management influence compost-amendment effects Immediate and temporal cumulative effects of compost on soil α and β diversity

Composting poultry carcasses and the infected litter is considered feasible during mass depopulation events in response to disease outbreaks. We demonstrate the effect of temperature (40, 50, 60 degrees C) and aerobic/anaerobic conditions on the degradation of broiler carcasses and broiler litter (BL) and the elimination of pre-inoculated Avian flu and Newcastle viruses and Salmonella Infantis (3.3 x 105.6 EID50, 7 x 106.0 EID50 and 2 x 107 CFU g-dry matter (DM)-1, respectively). Six broiler carcasses and BL were inoculated and treated with a water-based foam, simulating a common culling method. After 30 days of composting, both viruses were eliminated under all conditions, while Salmonella persisted at 40 degrees C under aerobic and anaerobic conditions (7.4 x 105 and 4.4 x 103 CFU g-DM-1, respectively). Mass losses were 42-44, 24-26, and 18-22% (aerobic) and 18-27, 21-23, and 0-7% (anaerobic) at 40, 50, and 60 degrees C, respectively. In the end, the associated odors were not typical of carcasses (aerobic), or they were strong and offensive (anaerobic). Considering the observed mass losses and biomass water holding capacity, we present a sensitivity analysis of the water balance expected in composting sleeves if they are utilized on mass depopulation events. Composting of the carcasses and the BL in enclosed sleeves with forced aeration, following culling by means of water-based foam will generate excess water, depending on sleeve volumes, aeration conditions, and co-addition of absorbing materials like sawdust. No excessive moisture is expected if dry culling methods are used.

Broiler litter (BL) is often contaminated by a variety of zoonotic pathogens. This study attempts to assess the persistence of Salmonella enterica serovar Infantis ( S . Infantis) in BL based on spatial and temporal variation of physicochemical properties in a stockpile and composting sleeve. A single trial of two pilot-scale setups, ~35 m 3 each, included an open static pile (stockpile) and composting in a polyethylene sleeve with forced aeration. The initial water content was adjusted only for the sleeve (~50% w/w) as in a common composting practice. Both systems were monitored weekly and then biweekly during 2 months in 47–53 sampling points each on every campaign. Measurements included temperature, water content, pH, electrical conductivity (EC), gas-phase oxygen, and ammonia, and the collected data were used to construct multiple contour grid maps. Of the stockpile volume, 83, 71, and 62% did not reach the commonly required minimum temperature of 55°C for three consecutive days during the first, second, and third weeks, respectively. Oxygen levels showed a strong gradient across the stockpile, while anaerobic conditions prevailed in the core. Variation was also recorded within the sleeve, but due to the water content adjustment and active aeration, the conditions favored more intense degradation and higher temperatures. Combining the grid maps drawn in this study with decay rate constants recently published for S. Infantis in BL under 36 combinations of temperature, water content, and pH, we assessed the spatial persistence of S. Infantis in the stockpile and the sleeve. Temperature was shown as a major factor, while water content and pH had only a small effect, in the stockpile only. Co-correlations between temperature, water content, EC, and oxygen suggest that selected physicochemical properties may be sufficient for such assessments. Up to 3 weeks would be recommended to achieve 7–8 log 10 reduction in Salmonella in a stockpile, while this would be fully achieved within 1 week in a sleeve. This approach of combining high-resolution spatial field sampling along with decay rates of pathogens under controlled lab conditions may improve quantitative microbial risk assessments and future regulations of manure utilization.

Broiler litter (BL), a by-product of broiler meat production, is frequently contaminated with Salmonella and other zoonotic pathogens. To ensure the safety of crop production chains and limit pathogen spread in the environment, a pre-treatment is desired before further agricultural utilization. The objective of this study was to characterize the effect of physico-chemical properties on Salmonella persistence in BL during composting and stabilization and following soil incorporation, toward optimization of the inactivation process. Thirty-six combinations of temperature (30, 40, 50, and 60°C), water content (40, 55, and 70%; w/w), and initial pH (6, 7, and 8.5) were employed in static lab vessels to study the persistence of Salmonella enterica serovar Infantis (S. Infantis; a multidrug-resistant strain) during incubation of artificially-inoculated BL. The effect of aeration was investigated in a composting simulator, with controlled heating and flow conditions. Temperature was found to be the main factor significantly influencing Salmonella decay rates, while water content and initial pH had a secondary level of influence with significant effects mainly at 30 and 40°C. Controlled simulations showed faster decay of Salmonella under anaerobic conditions at mesophilic temperatures (<45°C) and no effect of NH3 emissions. Re-wetting the BL at mesophilic temperatures resulted in Salmonella burst, and led to a higher tolerance of the pathogen at increased temperatures. Based on the decay rates measured under all temperature, water content, and pH conditions, it was estimated that the time required to achieve a 7 log10 reduction in Salmonella concentration, ranges between 13.7–27.2, 6.5–15.6, 1.2–4.7, and 1.3–1.5 days for 30, 40, 50, and 60°C, respectively. Inactivation of BL indigenous microbial population by autoclaving or addition of antibiotics to which the S. Infantis is resistant, resulted in augmentation of Salmonella multiplication. This suggests the presence of microbial antagonists in the BL, which inhibit the growth of the pathogen. Finally, Salmonella persisted over 90 days at 30°C in a Vertisol soil amended with inoculated BL, presumably due to reduced antagonistic activity compared to the BL alone. These findings are valuable for risk assessments and the formulation of guidelines for safe utilization of BL in agriculture.

Farmers apply broiler chicken litter to soils to enrich organic matter and provide crops with nutrients, following varying periods of stockpiling. However, litter frequently harbors fecal-derived microbial pathogens and associated antibiotic resistance genes (ARGs), and may be a source of microbial contamination of produce. We coupled a cutting-edge Loop Genomics long-read 16S rRNA amplicon-sequencing platform with high-throughput qPCR that targeted a suite of ARGs, to assess temporal (five time points over a 60-day period) and spatial (top, middle and bottom layers) microbiome and resistome dynamics in a broiler litter stockpile. We focused on potentially pathogenic species from the Enterobacteriaceae, Enterococcaceae and Staphylococcaceae families associated with food-borne disease. Bacterial diversity was significantly lower in the middle of the stockpile, where targeted pathogens were lowest and Bacillaceae were abundant. E. coli was the most abundant Enterobacteriaceae species, and high levels of the opportunistic pathogen Enterococcus faecium were detected. Correlation analyses revealed that the latter was significantly associated with aminoglycoside (aac(6')-Ib(aka aacA4), aadA5), tetracycline (tetG), vancomycin (vanC), phenicol (floR) and MLSB (mphB) resistance genes. Staphylococcaceae were primarily non-pathogenic, but extremely low levels of the opportunistic pathogen S. aureus were detected, as was the opportunistic pathogen S. saprophyticus, which was linked to vancomycin (vanSA, vanC1), MLSB (vatE, ermB) and tetracycline (tetK) resistance genes. Collectively, we found that stockpile microbiomes and resistomes are strongly dictated by temporal fluctuations and spatial heterogeneity. Insights from this study can be exploited to improve stockpile management practice to support sustainable antimicrobial resistance mitigation policies in the future.

The controlled application of olive mill wastewater (OMW) as a by-product of the olive oil extraction process is widespread in olive oil-producing countries. Therefore, a sustainable approach necessarily targets the positive effects of soil resilience between successive annual applications to exclude possible accumulations of negative consequences. To investigate this, we applied 50, 100, 100 with tillage and 150 m3 OMW ha−1 y−1 for five consecutive seasons to an olive orchard in a semi-arid region and monitored various soil physicochemical and biological properties. OMW increased soil water content with concentration of total phenols, cations, and anions as well as various biological and soil organic matter indices. Soil hydrophobicity, as measured by water drop penetration time (WDPT), was found to be predominantly in the uppermost layer (0–3 and 3–10 cm). OMW positively affected soil biology, increased the activity and abundance of soil arthropods, and served as a food source for bacteria and fungi. Subsequent shallow tillage reduced the extent of OMW-induced changes and could provide a simple means of OMW dilution and effect minimization. Despite potentially higher leaching risks, an OMW dose of 50–100 m3 ha−1 applied every two years followed by tillage could be a cost-effective and feasible strategy for OMW recycling.

On-site in-vessel composting of sewage sludge is considered to be applied in Israel for peripheral wastewater treatment plants (WWTPs). Based on lab-scale simulations using municipal sewage sludge and green waste, this study identifies a prospective range of values related to biomass stabilization during short-term processing. Within two weeks, 26–30% of the initial organic carbon was released as CO2, potential heat formation was decreased by 73–82%, and odor emissions by 87–99.5%. This reduction was mainly associated with co-decrease of NH3, dimethyl disulfide, and dimethyl trisulfide. Phytotoxicity was reduced by 28–52% whereas some residual toxicity might be attributed to non-biodegradable inorganic compounds. Stabilization rates observed in flexibly controlled lab-scale simulations can represent closed and efficiently aerated large-scale industrial systems. These prospective ranges of stabilization parameters are critical for deciding on the necessity of a curing stage for on-site enclosed installations in WWTPs.

Controlled spreading of olive mill wastewater (OMW) on cultivated soils is a low-cost disposal method of an otherwise problematic pollutant, with potential recycling of plant nutrients. The nutritional value of successive OMW applications was examined in an intensive olive orchard grown on sandy loam soil in a semi-arid region. Application at 50-150 m(3) ha(-1) y(-1) for 5 years had no negative effects on tree vegetative growth, fruit yield or oil quality. OMW application did not increase N content in the soil or plants; yet, it caused a consistent increase in soil P and K contents and significantly affected diagnostic leaf P and K concentrations. It also led to a significant increase in exchangeable potassium percentage (EPP) already from the first application, and soluble K migration to deep soil layers after 3 years of successive applications. Soil tillage after OMW application did not affect N, P or K dynamics in the soil or uptake of these nutrients by plants. Controlled application of OMW to intensive olive orchards can be a significant source of K and P and thus save on fertilizers without negatively affecting tree performance.

Several studies cautioned against potential negative effects of controlled olive mill wastewater (OMW) application on soil physical properties that could be associated with the possible adverse effects of K on soil structure stability. The objective of the study was to examine the effects of annual application of OMW over several years on selected physical properties of the upper soil layer (0-10cm) and their link to exchangeable K levels. Two experimental field platforms were studied: field crops grown in a tilled clay soil (3years of OMW application) and an olive orchard grown in a sandy-loam soil (5years of OMW application). In the clay soil, OMW application did not affect organic carbon (OC) and only slightly increased exchangeable potassium percentage (EPP) from 3.3 in the control to similar to 4.5 in the OMW-treated plots. In the sandy-loam soil, application of different rates of OMW resulted in an increase in both OC and EPP (>20) compared with the control (8). For both soils, addition of OMW improved aggregate stability; yet for the clay soil, the increase was not associated with changes in EPP or OC. In the sandy-loam soil, aggregate stability was positively correlated with OC and EPP. Soil hydraulic conductivity, tested for the sandy-loam soil only, was not affected by OMW application. Overall, our study shows that consecutive 3 to 5years of controlled OMW application in the range of 50-150m(3) OMW ha(-1) y(-1) does not result in the deterioration of soil physical and hydraulic properties.

Soil organic matter (SOM) plays a dominant role in the functionality of agricultural soils and particularly so in organic farming. Yet, there is limited knowledge on the effect of organic management in which the soil is subjected to incorporation of a variety of organic residues on the composition of SOM and water-extractable organic matter (WEOM) in top and sub-surface soil layers. The general objective of this study was to quantify depth-related changes in the composition of SOM and WEOM in an organically managed soil subjected to multiple compost applications, using spectroscopic techniques requiring no or minimal soil sample pre-treatment. We collected soil samples across the top 60 cm on October 2012 from an existing field experiment initiated in late 2009, which was organically fertilized by means of compost and green manure incorporation. Compost was applied at levels of 0 (control), 20, 40 and 60 m3 ha− 1, with the control treatment being fertilized with urea and amended with green manure. The collected samples were then used to characterize (i) SOM by FTIR absorbance associated with hydrophilic SOM functional groups and aliphatic CHs, total organic C and N contents, and (ii) WEOM by dissolved organic C (DOC) concentration, UV–VIS absorbance and fluorescent components identified following parallel factor analysis. In general, for all the studied attributes the core data tended to (i) increase after compost addition, although differences among the compost doses could not always be identified, and (ii) decrease with soil depth for all compost doses as well as the control treatment. Compost addition enriched soil by hydrophobic organic matter and water-extractable aromatic and, specifically, humic-like components. In the compost-amended soil, SOM became depleted of hydrophilic groups and enriched by hydrophobic aliphatic CH-rich substances. However, the content of hydrophilic organic matter in SOM was elevated with increasing depth.

Green manure (GM) cultivation and incorporation (i.e., GM management) may change soil organic matter (SOM) composition and the agroecosystem functioning. However, the understanding of GM effects on SOM composition, specifically in deeper soil layers, is limited. The objectives of this study were to examine the effects of GM management (as part of an organic agriculture practice), following two years of various doses of compost application, on the changes in SOM and water-extractable organic matter (WEOM) compositional characteristics up to a soil depth of 60cm. Soil samples from a two years compost amended field that was subsequently subjected to GM management were taken in four intervals to a depth of 60cm (0–5, 5–15, 15–30 and 30–60cm) and characterized for organic C content and SOM composition, by FT-IR transmission. Characterization of WEOM included excitation-emission matrices (EEMs) of fluorescence, UV absorbance and dissolved organic C (DOC) measurements. The response of SOM and WEOM to GM management resulted in some opposite trends. The SOM became rather aromatic, with aliphatic CH-containing structures contributing to a greater extent to SOM composition at deeper layers following GM management. By contrast, GM management resulted in (i) a substantial increase in dissolved organic C concentration, (ii) WEOM becoming enriched by hydrophilic aliphatic organic compounds, and (iii) aromatic and fluorescent components increasingly being found at deeper soil layers and hydrophilic aliphatic components at the surface soil. Fluorescent portion of WEOM became enriched by relatively less biodegradable and weaker-soil adsorbing humic-like components; this enrichment increased in deeper soil layers. The effects of past compost application rates on the changes in SOM and WEOM characteristics were either non-significant or negative. In the latter case, an increase in application rate decreased the changes in SOM content of hydrophilic groups and in the fractions of fluorescent components in WEOM. Growing and incorporating plant biomass may mask, at least on a short time scale, the effects of earlier compost applications on changes in SOM and WEOM compositional characteristics.

Controlled land spreading of untreated olive mill wastewater (OMW) has been widely practiced as a means of its disposal. However, potential phytotoxic effects are critical for the selection of sites and crop types and for proper synchronization between land application and cropping. This study traced the fate of dissolved organic carbon (DOC), total phenols (TP), electrical conductivity, pH, microbial counts, and phytotoxicity to cress ( L.) after soil application at doses equivalent to 80, 160, and 320 m ha. Vertisol (fine-clayey) and Loess (sandy loam) soils were treated and incubated at 12 or 25°C and at moisture contents maintained at 70% of field water capacity or gradually reduced from 70 to 20% without compensation. Temperature, rather than moisture content, had a major effect on removal rates of DOC and TP. The maximum combined effect of warm temperature and higher moisture content resulted in removal rates greater than those under cooler, drier conditions by factors of up to 1.8 and 4.1 for DOC and TP, respectively. Favorable biodegradation conditions were indicated by increased numbers of total soil microorganisms and fungi by factors of up to 26 and 5, respectively. A whole-soil bioassay was developed to assess the dynamics of residual soil phytotoxicity after OMW application. Phytotoxicity measurement in soil extract generally showed stronger inhibition or stimulation activity than measurement in whole soil, depending on soil type and OMW dose. The newly developed bioassay seems to be useful for the refinement of general recommendations regarding permitted OMW application doses.

Broomrape (Phelipanche and Orobanche spp.) are obligate holoparasites that attack roots of almost all economically-important crops in semiarid regions of the world. Broomrape seeds are extremely small (dust-like seeds), averaging 200 to 300 μm in size and because of the miniscule seed size it is difficult to detect and confirm via conventional methods. In this study our aim was to develop a PCR-based assay specific for broomrape soil-borne seeds and sensitive enough to detect a single or few broomrape seeds in a soil sample. For this purpose, we used complementary polymerase chain reaction (PCR) primers based upon unique sequences in the internal transcribed spacer (ITS) regions of the nuclear ribosomal DNA of Phelipanche aegyptiaca. Genomic DNA was extracted from soil samples artificially infested with broomrape seeds or tissue of Phelipanche aegyptiaca Pers., Orobanche cumana Wallr. and Phelipanche crenata Forsk. and subjected to PCR analysis. Using ITS-350 primers, a specific PCR product (350 bp) was amplified and detected in all samples containing broomrape species, but was not detected in soil sample free of broomrape seeds or tissues. Additionally, the PCR-based assay was sensitive enough to detect even a single broomrape seed in the soil. As expected the universal internal control primers amplified a PCR product (555 bp) of genomic DNA extracted from soil samples with or without broomrape tissues or seeds. This diagnostic method is simple, reliable and rapid and could help for assessment of broomrape seed contamination in a crop field.

Controlled land spreading of olive mill wastewater (OMW) is now adopted in several Mediterranean countries as a practical alternative for its disposal. This approach has been supported by a large number of studies showing the potential fertilization value of OMW and the absence of negative effects on soil properties. In Israel, the current experience is limited. A few spreading activities have been managed and monitored by the Israel Ministry of Environmental Protection. More detailed information is available from two experiments conducted under controlled conditions in Newe Ya'ar (Jezre'el Valley, northern Israel) and from commercial spreading done in the olive orchard of Revivim (Negev, southern Israel). A short-term increase in soil phytotoxicity (a bioassay with cress, Lepidium sativum L.) was observed in Newe Ya'ar, whereas the soil partly or completely recovered between successive applications. In Revivim, no phytotoxicity was measured across soil profiles. Yet, the collected information shows potential leaching of organic constituents (expressed as dissolved organic carbon, DOC) and phenolic compounds (measured as total phenols, TP), as well as accumulation of presumably the more recalcitrant organic constituents. Surface spreading may cause more leaching as compared to application followed by tillage. Soil microbial activity was generally enhanced by OMW application; in Revivim, the application of OMW caused a temporary increase in the numbers of soil bacteria and fungi, whereas after degradation of the more labile fraction, the number of fungi increased in correlation to TP concentrations. A similar DOC/TP ratio was observed in Revivim across soil profiles, suggesting no selective degradation of OMW in the upper as compared to deeper soil layers. A judicious selection of sites that are safe for OMW spreading is currently hampered by the limited knowledge about potential transport and biodegradation rates under field conditions, on one hand, and the lack of hydrological sensitivity maps of suitable resolution, on the other hand. Until a detailed study is completed that will support safe spreading, it is recommended that future OMW applications be restricted to cases of unavoidable OMW release, and not used as a widely-accepted disposal approach. Co-composting of OMW with various agricultural solid wastes is suggested as a safer recycling alternative.

Excitation–emission matrix fluorescence spectroscopy, combined with parallel factor analysis and measurements of UV absorption and dissolved organic carbon (DOC) concentrations, was used to trace the footprints of industrial effluents discharged into the lower Kishon River (Israel). The lower Kishon River typifies streams that are affected by seawater tidal intrusion and represents an extreme case of severe long-term pollution caused mainly by a variety of industrial effluents. The industrial effluents may contribute about 90%, in terms of biochemical oxygen demand, of the total organic carbon discharged into the lower Kishon River. Water samples were collected along the river, including the points of effluent discharge from industrial plants, between November 2005 and September 2006. Two types of fluorescent components characterized the fluorescence of the lower Kishon River water: component I corresponded to humic-like matter and component II spectrally resembled material known to be associated with biological productivity, but different from typical tryptophan-like fluorophore. These fluorescent components and other substances that absorbed light at 254 nm contributed to the DOC pool that resisted riverine microbial degradation under laboratory conditions, and that constitutes up to 70% of the overall riverine DOC. The variations in DOC concentration, absorbance at 254 nm, and concentration of humic-like matter (characterized by component I) correlated with the distance from the sea and the water electrical conductivity, and were linked to seawater tidal intrusion. The increased concentration of component II, as well as its enlarged fraction in the overall riverine DOC pool, was found to be associated with the location of major inputs of the industrial effluents. These findings support the use of this fluorescent component as an indicator of industrial pollution in such severely contaminated riverine systems.

Field odor assessors are required to rate or describe several odor parameters, such as intensity, duration, offensiveness, and character. Ideally, their assessments should reflect the average odor perception of a specific community. The authors developed a three-part screening test for recruiting odor assessors: (1) distinguishing between different odorants by means of a triangular forced-choice test; (2) evaluating odor intensity; and (3) describing hedonic tone and odor character. Grading was based on two criteria: correctly answering the relevant parts of the test, and evaluation of odor parameters relative to the entire tested population. The latter involved grading each tested individual according to the similarity of their score to the average result of 179 tested individuals, comprising 48% women and 52% men whose age and residence distributions were identical between women and men (except for the oldest group). To exclude relatively less sensitive individuals who showed poor ability to distinguish between different odorants and various odor intensities, and/or provided atypical description (or rating) of odor intensity, character, and offensiveness, it was suggested that only individuals whose final score was within the upper 75% (final score +/- 80.75) would be qualified as odor assessors. According to this criterion, 73.8% of men and 78.6% of women passed the test. Among urban and rural dwellers, 77.4% and 67.4%, respectively, were qualified. Pass rate clearly diminished with increasing age: from 89.3% at 21-30 years to 54.6% at 61-70 years. This screening tool is recommended by the Israel Ministry of Environmental Protection for selection of field odor assessors to serve the general community and regulatory authorities.

Advanced oxidation technologies such as various combinations of UV/TiO(2)/O(3) have the potential to decompose multiple odorous volatile organic compounds (VOCs). Only limited work has been devoted to investigate the potential of these methods to treat real odors emitted from various agricultural and industrial sources. The present study explores the effectiveness of UV/TiO(2) photocatalysis to treat the odors associated with poultry manure. A dynamic (flow-through) setup was built in which the odor source was obtained by purging fresh or aged suspension of poultry manure. The photoreactor was constructed out of a 2.5-liters quartz tube which was surrounded by a ring of 24 individually controlled 18W "black light" lamps (365 nm). A TiO(2)-coated support was placed inside the reactor. The effectiveness of the various treatments was assessed by analyzing specific odorants (using headspace solid phase microextraction followed by GC-MS) and collecting the total air in Tedlar bags for odor analysis by dynamic olfactometry. Ammonia was measured with Kitagawa color tubes. Samples were withdrawn through ports before and after the photoreactor, and the effectiveness of treatments was assessed as percent removal for each target compound based on peak area counts obtained for separate VOCs or concentrations of ammonia obtained by the color tubes. Experiments were designed to examine the effect of flow rates (i.e. residence time), number of lamps in use (i.e. energy dose), and the role of TiO(2). Removals of key manure-associated odorants, such as dimethyl disulfide, dimethyl trisulfide and p-cresol, were between 80 to similar to 100% (decreased to below detection limit). The total odor was reduced by 75% in one experiment with fresh manure suspension (starting from about 70,000 odour units, OU) and was not reduced much in another experiment with aged manure suspension (starting from about 700 OU) The latter was presumably due to the contribution of odor from trace levels of ozone which was generated under the photocatalytic conditions. Ammonia was reduced between 0-50% in the various treatments. The reported removals were obtained for residence times ranging from only a few and up to a maximum of about 10 seconds. After optimization, this approach may become applicable for the treatment of outflow air at mechanically-ventilated barns.

The effect of storage conditions on compost suppressiveness against fusarium wilt of melon, caused by Fusarium oxysporum f. sp. melonis (FOM) was studied in relation to the dynamics of compost microbial activity and biodegradability. For this purpose, mature suppressive compost, prepared from tomato plants and separated cow manure, was divided into four portions and stored for one year under cool/warm (12 or 28 degrees C) or dry/wet (15-35 or 55-65% moisture content) conditions, in four different combinations: cool-dry, warm-dry, cool-wet and warm-wet. All composts retained and even enhanced their suppressive capacity during storage, with no significant differences among them by the end of the storage period. However, significant differences were found in the dynamics of some of the measured chemical and microbial properties. The microbial activity of composts stored under wet conditions was higher than that of those stored under dry condition, which resulted in a substantial decrease in dissolved organic matter content (expressed as dissolved organic carbon; DOC) and increase in its recalcitrance to biological degradation, decrease in basal heat emission, slower response to added glucose or citric acid, and higher NO3 concentration, indicating increased nitrification under wet conditions. The DOC significantly correlated with several microbial properties as well as with compost suppressiveness of fusarium wilt of melon seedlings, and may be regarded as a most suitable general index for compost maturity. A best-subset multiple linear regression analysis revealed that the three best predictors, namely dissolved organic carbon (DOC), basal heat, and mesophilic bacterial counts, could explain as much as 83% of the total variance in compost suppressiveness. The generally agreed association between compost maturity and suppressiveness was verified in this case. It appears that compost microbial populations might compete and interfere with the saprophytic stage of FOM conidia, between germination and host invasion. In conclusion, it was demonstrated that compost suppressiveness against fusarium wilt of melon can be maintained for at least one year under a wide range of storage conditions, without any loss of suppressive capacity. This fact has positive logistical implications for the use of suppressive composts against FOM. (c) 2010 Elsevier Ltd. All rights reserved.