Field studies on two rock phosphate solubilizing actinomycete isolates as biofertilizer sources

Recently biotechnology is focusing attention on utilization of biological resources to solve a number of environmental problems such as soil fertility management. Results of microbial studies on earthworm compost in the University of Nigeria farm identified a number of rock phosphate solubilizing actinomycetes. Two of these, isclates 02 and 13, were found to be efficient rock phosphate (RP) solubilizers and fast-growing cellulolytic microbes producing extracellular hydrolase enzymes. In this preliminary field study the two microbial isolates were investigated with respect to their effects on the growth of soybean and egusi as well as their effect on the incidence of toxicity of poultry droppings. Application of these isolates in poultry manure-treated field plots, as microbial fertilizers, brought about yield increases of 43% and 17% with soybeans and 19% and 33% with egusi, respectively. Soil properties were also improved. With isolates 02 and 13, the soil available phosphorus increased at the five-leaf stage, while N-fixation in the soil increased by 45% or 11% relative to control. It was further observed that air-dried poultry manure after four days of incubation was still toxic to soybean. The toxic effect of the applied poultry manure was reduced or eliminated with microbial fertilizers 02 or 13, respectively. The beneficial effects of the microbial organic fertilizer are discussed. Justification for more intensive research on rock phosphate organic fertilizer is highlighted.     

Arsenic-speciation in arsenate-resistant and non-resistant populations of the earthworm,Lumbricus rubellus

Arsenic speciation was determined in Lumbricus rubellus Hoffmeister from arsenic-contaminated mine spoil sites and an uncontaminated site using HPLC-MS, HPLC-ICP-MS and XAS. It was previously demonstrated that L. rubellus from mine soils were more arsenate resistant than from the uncontaminated site and we wished to investigate if arsenic speciation had a role in this resistance. Earthworms from contaminated sites had considerably higher arsenic body burdens (maximum 1,358 mg As kg-1) compared to the uncontaminated site (maximum 13 mg As kg-1). The only organo-arsenic species found in methanol/water extracts for all earthworm populations was arsenobetaine, quantified using both HPLC-MS and HPLC-ICP-MS. Arsenobetaine concentrations were high in L. rubellus from the uncontaminated site when concentrations were expressed as a percentage of the total arsenic burden (23% mean), but earthworms from the contaminated sites with relatively low arsenic burdens also had these high levels of arsenobetaine (17% mean). As arsenic body burden increased, the percentage of arsenobetaine present decreased in a dose dependent manner, although its absolute concentration rose with increasing arsenic burden. The origin of this arsenobetaine is discussed. XAS analysis of arsenic mine L. rubellus showed that arsenic was primarily present as As(III) co-ordinated with sulfur (30% approx.), with some As(v) with oxygen (5%). Spectra for As(III) complexed with glutathione gave a very good fit to the spectra obtained for the earthworms, suggesting a role for sulfur co-ordination in arsenic metabolism at higher earthworm arsenic burdens. It is also possible that the disintegration of As(III)-S complexes may have taken place due to (a) processing of the sample, (b) storage of the extract or (c) HPLC anion exchange. HPLC-ICP-MS analysis of methanol extracts showed the presence of arsenite and arsenate, suggesting that these sulfur complexes disintegrate on extraction. The role of arsenic speciation in the resistance of L. rubellus to arsenate is considered.     

The impact of multiple source feedback on management development: findings from a longitudinal study

Despite the rapid uptake of multi‐source multi‐rater (MSMR) feedback systems by UK organizations, comparatively little research exists describing the actual impact on participant managers, in terms of changes in management competence. Ratings of 104 target managers (by self assessments, bosses‐, first‐ and second‐level subordinates) were investigated within the context of a developmental feedback programme in operation within an organization. The study compared ratings over two administrations (with two years between administrations) to determine: (1) changes in co‐workers' perceptions of their target manager's competence, (2) changes in target managers' development needs over time, (3) factors influencing a target manager's revised self‐assessment and co‐workers ratings, (4) changes in congruence between self and co‐workers ratings and (5) the relationship of feedback to the organization's formal performance appraisal process. Significant increases in managers' competence were perceived by the managers' themselves and by their subordinates, development needs were seen to reduce and self and co‐workers ratings were largely seen to become more congruent. However, polynomial regression analyses revealed co‐workers feedback at Time One was not predictive of targets' self‐assessments at Time Two. The implications of these findings with regard to the utility of MSMR feedback as a tool for management development are discussed. Copyright © 2002 John Wiley & Sons, Ltd.     

Composites Produced from Natural Rubber and Chrome-Tanned Leather Wastes: Evaluation of their In Vitro Toxicological Effects for Application in Footwear and Textile Industries

A new composite has been developed from natural rubber and chrome-tanned leather waste for use in footwear and textile industries. The contribution of this material to environmental quality and sustained development should be highligh because chrome tanned leather wastes, a major environmental problem, can be recycled. However, the safety of this new material for human use is questionable, as it is already well reported in the literature that chromium, particularly in its hexavalent oxidation state, can be genotoxic and carcinogenic to living beings. Thus, the aim of this study was to evaluate in vitro biocompatibility of this composite material for possible use in the footwear and textile industries, through cytotoxicity, cell adhesion, and genotoxicity tests. Inductively coupled plasma optical emission spectrometry (ICP-OES) was used to measure both concentrations of total and hexavalent chromium. Based on the findings, it was concluded that the composite exhibits low levels of cytotoxicity and genotoxicity, and possesses favorable properties for initial cell adhesion. Furthermore, it was verified that the composites released low concentrations of chromium and that the predominant species released would be trivalent chromium. The results of the present study open the possibility of the incorporation of solid residues of tanned leather into chromium without necessarily the chromium contained in these residues influences the toxicity and genotoxicity of this new material.     

Discussion: “Meadow Restoration Increases Baseflow and Groundwater Storage in the Sierra Nevada Mountains of California” by Luke J.H. Hunt,Julie Fair,and Maxwell Odland

We discuss a recent paper which evaluated the hydrologic changes resulting from a pond‐and‐plug meadow restoration project in the Sierra Nevada Mountains of California. In the study, measurements of streamflow into and out of the meadow suggested late‐summer baseflow increased as much as five‐fold when compared with prerestoration conditions. However, the volume of streamflow attributed to the restored meadow (49,000–96,000 m³ over four months) would require that 2.5–4.8 m of saturated meadow soils drain during summer months. The groundwater data from this meadow record only 0.45 m of change over this timeframe, which is less than might be expected from plant use alone (0.75 m), suggesting this restored meadow may be acting as a water sink throughout summer rather than a source.     

Refugees,water balance,and water stress: Lessons learned from Lebanon

Ambio - The Syrian crisis caused a massive influx of displaced people into neighboring countries, with Lebanon hosting the highest per capita number of refugees (3:10). Water remains the most...     

Planning routes around the world: International evidence for southern route preferences

Three studies test whether the southern route preference, which describes the tendency for route planners to disproportionately select south- rather than north-going routes, can be attributed to regional elevation patterns; specifically, we ask whether this effect replicates in three topographically disparate international regions, one of which is characterized by higher elevations to the north and lower to the south (Padua, Italy), and two characterized by higher elevations to the south and lower to the north (Enschede, Netherlands; Sofia, Bulgaria). In all cases, we found strong evidence that route planners disproportionately select south- rather than north-going routes at rates exceeding chance. We conclude that the southern route preference is driven by strong associations between canonical direction and perceived effort of route traversal; these effects are somewhat perplexing given that such associations are not founded in the reality of physical space.     

The safety policies and practices of community multi-purpose recreation facilities

This research investigated the under-explored area of safety in multi-purpose recreation facilities (MPRFs). Facility managers and other managerial staff (key informants) from four MPRFs in Victoria, Australia participated in semi-structured interviews. Safety was considered important from Occupational Health and Safety (OH&S), business viability and legal liability perspectives but not from a health promotion or public health point of view. Most implemented injury prevention measures required gymnasium and pool staff or users to change their behaviours. Awareness of safety standards was higher for some operational areas (e.g. aquatics, child-care) than others (e.g. gymnasium, group fitness activities). Key informants struggled to keep abreast of legislation changes and they relied on commercial, regulatory, and industry information sources rather than evidence of best practice. Reported factors influencing safety in MPRFs were classified into three types: internal (e.g. training, culture); external (e.g. weather, demographic change); and governance (e.g. insurance, industry standards). Comprehensive, relevant and accessible industry safety standards, which focus not only on OH&S but equally on health promotion principles and public health perspectives linked to injury prevention, are required. Training is needed to reflect these broader and equally important perspectives. Health/injury, fitness/recreation and insurance sector links should be improved to ensure a consistent, sustainable approach to safety.     

Significant rainfall decreases and variations of the atmospheric circulation in the Mediterranean (1950–2000)

This paper aims at identifying the link between significant rainfall decreases (1950–2000) in the Mediterranean basin and the atmospheric circulation at the 500 hPa level. The months and seasons of the subregions with significant rainfall decrease during this period have been identified previously (Norrant and Douguédroit, Theor Appl Climatol 83(1–4):89–106, 2006): October in the Mediterranean Iberia, March in the Atlantic Iberia, January and winter in Greece, and winter in the Near East. Canonical Correlation Analyses based on the monthly and daily data records from 62 rainfall stations and 138 grid points at the 500 hPa level over a Euro-Atlantic window were first calculated to define the TeleConnection Patterns explaining significant regional rainfall decreases. Then, 500 hPa level weather types (ZWTs) of the rainy days with important or little rainfall associated with each Teleconnection Pattern were identified in each subregion. Rainfall-causing disturbances from the Atlantic reach Iberia directly; some of them are regenerated if they reach the Mediterranean. Other disturbances are generated locally near Greece and the Near East (Meteorological Office in Weather in the Mediterranean I: general meteorology, Her Majesty’s Stationery Office, London, 1962). The relationship between significant rainfall decreases and the corresponding 500 hPa level appears to be a nonlinear phenomenon. In all of the studied subregions, a break during the 1970s separates two subperiods differing significantly from each other. Rainfall decrease is due to the higher frequency of important rainfall ZWTs over low rainfall ZWTs, during the first period, which the opposite is true during the second period. Such an inversion could be partially linked with the prevailing North Atlantic Oscillation-positive phase during the last quarter of the twentieth century.     

Lead (Pb) quantification in potable water samples: implications for regulatory compliance and assessment of human exposure

Assessing the health risk from lead (Pb) in potable water requires accurate quantification of the Pb concentration. Under worst-case scenarios of highly contaminated water samples, representative of public health concerns, up to 71–98 % of the total Pb was not quantified if water samples were not mixed thoroughly after standard preservation (i.e., addition of 0.15 % (v/v) HNO₃). Thorough mixing after standard preservation improved recovery in all samples, but 35–81 % of the total Pb was still un-quantified in some samples. Transfer of samples from one bottle to another also created high errors (40–100 % of the total Pb was un-quantified in transferred samples). Although the United States Environmental Protection Agency’s standard protocol avoids most of these errors, certain methods considered EPA-equivalent allow these errors for regulatory compliance sampling. Moreover, routine monitoring for assessment of human Pb exposure in the USA has no standardized protocols for water sample handling and pre-treatment. Overall, while there is no reason to believe that sample handling and pre-treatment dramatically skew regulatory compliance with the US Pb action level, slight variations from one approved protocol to another may cause Pb-in-water health risks to be significantly underestimated, especially for unusual situations of “worst case” individual exposure to highly contaminated water.