ABSTRACT Despite promoting positive employee outcomes, servant leaders may become the victim of manipulation by followers. The current study investigates this underexplored side of servant leadership by examining the employee-related outcomes of the interaction between servant leadership and follower Machiavellianism through mediating mechanism of exploitative manipulative behavior. It is argued that employees high in Machiavellianism engage in exploitative manipulative behavior to achieve subjective career success and social power while working with a servant leader. We used PROCESS macro to analyze our mediation and moderated mediation hypotheses, respectively. We collected data in a time-lagged design (three-time lags) from 320 dyads (self and peer) responses from service sector organizations. The results fully supported our hypotheses. Limitations and future research directions are also presented.

RESUMEN A pesar de que fomenten resultados positivos en los empleados, los líderes servidores pueden convertirse en víctimas de la manipulación por parte de los subordinados. Este estudio investiga esta faceta poco explorada del liderazgo de servicio por medio del análisis de los resultados de los empleados relativos a la interacción entre el líder servidor y el maquiavelismo de los subordinados a través del mecanismo mediador del comportamiento manipulativo explotador. Se argumenta que los empleados con un maquiavelismo elevado se comportan de un modo manipulativo explotador, con el fin de lograr un éxito subjetivo en su carrera profesional y poder social cuando trabajan con un líder servidor. Empleamos el macro PROCESS para analizar nuestras hipótesis de mediación y mediación moderada, respectivamente. Recogimos datos en un diseño demorado en el tiempo (con tres retrasos temporales) a partir de respuestas de 320 díadas (de uno mismo y de compañeros) de empresas del sector servicios. Los resultados avalan plenamente nuestras hipótesis. Se comentan igualmente las limitaciones y perspectivas de investigación futura.

Abstract: Application of composted manures has previously been proposed as soil amendments capable of retarding nutrients losses via surface runoff, thereby stimulating infiltration rates. A study was carried out under natural rainfall conditions to assess the effects of cow manure after composting with maple and poplar leaf litter on nutrient runoff from two types of soils, a sandy loam and silt loam. Composted manure without added leaf litter to the soil was considered as a control treatment. Cow manure co-composted with leaf litter at four ratios (1:0, 1:1, 1:2 and 1:3). Soils were packed in the plastic lined wooden trays and the soil surface was mixed with the co-composted manure at rates of 10 and 20 t ha-1. Runoff samples were collected from the sloped trays (5%) during three rainfall events. Inorganic N (NO3 plus NH4), P and K concentrations were measured in the runoff. Application of manure amendments derived from composting with leaf litter to the soil reduced the nutrients losses in the order of 1:3 < 1:2 < 1:1 <1:0 regardless of the kind of leaf litter used. Irrespective of soil and application rates, N losses in the runoff were lowered with manure co-composted with leaf litter. Nutrients losses in the runoff were enhanced with higher manure application rates, depending on the type of the soil treated. It was concluded that application of manure amendments derived from composting with plant leaf litter was a useful option in reducing nutrients losses from soils.

Intensive livestock production and poor agricultural management have resulted to excessive loading of soil with phosphors (P), thereby contributing to environmental pollution and impairment of water quality. A study was carried out to determine the extractability and bioavailability of P in soils treated with poultry litter (PL) co-composted with sugarcane and cabbage wastes. The manure was applied based on total P contents at 200 and 400 kg P ha-1, with maize (Zea mays L.) as the test crop. The co-composted PL increased maize growth relative to PL alone with the best growth occurring at the treatment rate of 400 kg P ha-1. Maize biomass and available P in soil varied in the order PL co-composted with sugarcane waste and cabbage waste (%) 50 > 33 > 25 > 0. Phosphorus contents in maize shoot were higher in sandy clay than silt loam soil and its recovery was higher in soil treated with PL co-composted sugarcane waste than co-composted with cabbage waste. An amendment with co-composted PL increased the extractable P fractions and P availability in the soils. The P fractions in the post-harvest soils varied in the order HCl-P > H2O-P > NaHCO3-P > NaOH-P and the fractions were significantly higher in the sandy clay than the silt loam soil. Also, the PL co-composted with sugarcane waste exhibited higher levels of P fractions in soils than co-composted with cabbage waste. Thus, co-composting poultry manure with crop wastes would better improve plant growth and P nutrition than sole-composted manure.

Abstract Contaminants like nitrate (NO3), phosphorus (P) and heavy metals in water are often associated with agricultural activities. Various soil and water remediation techniques have been employed to reduce the risk associated with these contaminants. A study was conducted to examine the extent of leaching of heavy metals (Cd, Ni, Pb and Cr), NO3 and P. For this purpose sandy and silt loam soils were amended with different waste materials, namely wood ash, solid waste ash, vegetable waste, charcoal, and sawdust. The soils were saturated with wastewater. Irrespective of the waste applied, the pH and EC of the amended soils were found to be greater than the control. Charcoal, sawdust and wood ash significantly decreased heavy metals, nitrate and phosphorus concentrations in the leachate. Treatments were more efficient for reducing Ni than other heavy metals concentrations. Waste amendments differed for heavy metals during the process of leaching. Heavy metals in the soil were progressively depleted due to the successive leaching stages. This research suggests that waste material may act as an adsorbent for the above contaminants and can reduce their leachability in soils.