C. J. Pilbeam

The governance of supply networks: a systematic literature review

Purpose – The purpose of this paper is to establish what is known regarding how supply network governance leads to network outcomes, what mechanisms underlie this relationship, and how context impacts it.Design/methodology/approach – A systematic literature review identified 44 conceptual and empirical studies. Purely dyadic studies were excluded. Synthesis used the context‐intervention‐mechanism‐outcomes (CIMO) logic.Findings – From a categorization of contexts, governance instruments, mechanisms and outcomes a contingent conceptual framework is developed in the paper relating governance instruments to network outcomes dependent on the context. In general, formal instruments are adopted in dynamic and unstable circumstances defined as risky, uncertain, unpredictable or during organizational change. These instruments can result in coordination, control, viability and performance outcomes. Informal instruments tend to be adopted in contexts where prior relationships exist between actors.Research limitation...

Nestlé Nespresso AAA sustainable quality program: an investigation into the governance dynamics in a multi‐stakeholder supply chain network

Purpose – Within the context of a sustainable supply chain, the purpose of this paper is to report on empirical longitudinal research on supply chain network evolution and dynamics of governance in a multi‐stakeholder supply chain sustainability initiative led by Nespresso, the speciality coffee division of Nestle.Design/methodology/approach – The paper proposes a framework to study the creation and evolution of governance mechanisms over a five‐year period. Data from 48 semi‐structured interviews and 15 recent and historic documents were also analysed. The interviews were conducted among current and past representatives of all the organisations concerned including coffee traders, NGOs and farmers.Findings – In contrast with literature on the subject, governance mechanisms initially relied mostly on informal mechanisms. Formal governance mechanisms were incorporated into the relationships to enable the supply chain network to grow and to provide clarity to all actors. Relational quality processes that inc...

Effect of climate on the recovery in crop and soil of15N-labelled fertilizer applied to wheat

Data was assembled from experiments on the fate of15N-labelled fertilizer applied to wheat (Triticum spp.) grown in different parts of the world. These data were then ranked according to the annual precipitation-evaporation quotient for each experimental location calculated from the average long-term values of precipitation and potential evaporation. Percentage recovery of15N fertilizer in crop and soil varied with location in accordance with the precipitation-evaporation quotient. In humid environments more15N fertilizer was recovered in the crop than in the soil, while in dry environments more15N fertilizer was recovered in the soil than in the crop. Irrespective of climatic differences between locations 20% (on average) of the15N fertilizer applied to wheat crops was unaccounted for at harvest. Most of the15N fertilizer remaining in the soil was found in the 0–30 cm layer. The most likely explanation of these differences is that wheat grown in dry environments has a greater root:shoot ratio than wheat grown in humid environments and, further, that the residue of dryland crops have higher C/N ratios. Both factors could contribute to the greater recovery of15N fertilizer in the soil in dry environments than in humid ones.

Lone scholar or community member? The role of student networks in doctoral education in a UK management school

Doctoral education in the UK embraces both independent self‐directed study and collective shared learning. The extent to which individual doctoral students remain isolated, or become integrated into a network of doctoral students, is a function of the attributes of the individual and the nature of the doctorate and its mode of delivery. Using the techniques of social network analysis, this cross‐sectional study investigated the extent of the connections between doctoral students, and the purposes these connections served amongst the doctoral community, comprising full‐time and part‐time PhD and Doctor of Business Administration students at Cranfield School of Management. The study shows that ties between students served multiple purposes. Generally students were connected to others studying in the same mode and who entered at the same time. Connectivity was unaffected by nationality or gender.

Effect of fertilizer rate and form on the recovery of 15N-labelled fertilizer applied to wheat in Syria

15 N-labelled fertilizer was applied at different rates (0, 30, 60, 90 kg N ha −1 ) and in different forms (urea or ammonium sulphate) to wheat grown in Syria in three seasons (1991/92, 1992/93 and 1994/95). Recovery of 15 N-labelled fertilizer in the above-ground crop at harvest was low (8–22%), with the amount of 15 N-labelled fertilizer recovered in the crop increasing as the rate of application increased. Fertilizer application caused a significant increase in the amount of unlabelled soil N in the crop, suggesting that the application of N fertilizer caused a ‘real’ added nitrogen interaction. Recovery of 15 N-labelled fertilizer in the crop was unaffected by the form of the fertilizer. On average 31% (14–54%) of the 15 N-labelled fertilizer remained in the soil at harvest, mostly in the 0–20 cm layer. At the lowest application rate (30 kg N ha −1 ) most of the residual fertilizer was as organic N, but at the higher application rates (60 and 90 kg N ha −1 ), a greater proportion of the 15 N-labelled fertilizer was recovered as inorganic N, presumably as the result of top-dressing N in dry conditions in the spring. The amount of 15 N-labelled fertilizer remaining in the soil increased as the fertilizer rate increased, but was unaffected by the form of fertilizer applied. Losses of 15 N-labelled fertilizer were large (>35%), probably caused by gaseous losses, either through volatilization of N from the calcareous soil, or through denitrification from wet soils rich in organic residues. N fertilization strategies in the West Asia/North Africa (WANA) region should take note of the low recovery of N fertilizer by the crop in the season of application, and the resultant large quantities of residual fertilizer.

Nitrogen use in maize-grain legume cropping systems in semi-arid Kenya

Locally suitable cultivars of maize, beans, and cowpeas were grown in field experiments for four seasons in semi-arid Kenya. For three seasons, the dry matter production and grain yield of maize and beans were not increased by N fertilizer additions up to 120 kg N ha-1. Fertilizer recoveries measured by 15N isotope dilution techniques were low, less than 20%. Inoculated and uninoculated beans failed to fix N2. By contrast the cowpea derived 50% of its N from fixation, equivalent to 197 kg N ha-1. The N content of the grain generally exceeded 40 kg N ha-1, and the N content of the seeds from the grain legumes were greater than those from the cereals. Large inputs of N fertilizer or N by fixation are required if maize-grain legume cropping system in semiarid Kenya are to be sustained in the long term.

Soil matric potential effects on gross rates of nitrogen mineralization in an orthic ferralsol from Kenya

Abstract Gross rates of ammonification were measured over 9 days by 15N isotope dilution techniques allied to a mathematical model in an Orthic Ferralsol from Kenya. Rates of mineralization in soils conditioned for 24 days at different constant gravimetric moisture contents increased from 0.08 μg−1 Ng−1 d−1 for both ammonification and nitrification at −5.91 MPa to 2.12μg Ng−1d−1 ammonification at −0.063 MPa. In soil which had been conditioned constantly at −5.91 MPa then wetted to −0.42 MPa, gross mineralization rates were immediately stimulated. Wetting a soil conditioned at −0.42 MPa had no effect on rates of gross mineralization over 9 days.

Analysis of maize–common bean intercrops in semi-arid Kenya

Maize ( Zea mays L.) and common bean ( Phaseolus vulgaris L.) were each sown at four plant densities, including zero, in a bivariate factorial design at Kiboko Rangeland Research Station, Kenya during the long and short rains of 1990. The design gave nine intercrops with different proportions of maize and beans, and six sole crops, three of maize and three of beans. Seed yields in both the sole crops were not significantly affected by plant density, so the mean yield was used to calculate the Land Equivalent Ratio (LER), which averaged 1·09 in the long rains but only 0·87 in the short rains. These low values were apparently due to the fact that beans failed to nodulate and fix nitrogen in the study area. The difference in LER between seasons was probably caused by differences in the amount and distribution of rain in relation to crop growth. Maize was more competitive than bean, each maize plant being equivalent to between 0·7 and 3·4 bean plants depending upon the treatment and the season.

Transpiration efficiencies of maize and beans in semi-arid Kenya

Maize and bean were grown under varying levels of nitrogen fertilizer, plant population, and irrigation at Kiboko, Kenya in the short rains 1990, 1991, 1992 and the long rains 1991. The production of dry matter was not affected significantly by any treatment, because treatments only had a small impact on the balance between evaporation and transpiration. In all seasons the greatest loss of water from the profile was through direct evaporation from the soil surface. Transpiration was always less than 25% of rainfall. The ratio of transpiration (T) to evapotranspiration (E + T) was small (0.23), but increased from 0.15 to 0.40 as rainfall increased from 158 mm in the long rains 1991 to 470 mm in the short rains 1992. Treatments had little impact on the balance between transpiration and evaporation from the soil surface. The average transpiration efficiencies for maize and bean were 89 and 29 kg shoot dry matter ha−1 mm−1, respectively. For each crop there was a 60% change in transpiration efficiency between the short and the long rain season which could be accounted for by differences in saturation vapour pressure deficit.

Response of wheat-rice and maize/millet systems to fertilizer and manure applications in the mid-hills of Nepal.

Farmers in the mid-hills of Nepal have a mix of rainfed land on which millet is grown in relay after maize (maize/millet), and irrigated land on which wheat is grown sequentially after rice (wheat-rice). Double cropping is the norm but the diminishing quantities of organic materials, coupled with the trend towards increased use of inorganic fertilizers, have raised questions about the long-term productivity and sustainability of the cropping systems. The aim of this work was to examine the long-term effects (eight years) on grain yield of additions of manure and fertilizer either singly or in combination. Maize/millet and wheat-rice rotations were established on a Dystochrept at Pakhribas Agricultural Centre at about 1450m altitude. Manure and fertilizer applications were applied to the maize (eight combinations in May) and the wheat (different rates in seven combinations in November) every year with the succeeding crops (millet and rice) utilizing residual nutrients. Yields of maize, millet and rice were greater when manure rather than fertilizer was applied but yields of wheat were less. The combined application of manure and fertilizer significantly increased yields of maize and wheat compared with applications of either manure or fertilizer alone. However, for the subsequent crops (millet and rice) there was either a small residual benefit of the combined application when compared with fertilizer alone, or no benefit when compared with manure alone. Overall, the combined application increased total grain yields by about 35% in the maize/millet rotation and by 16% in the wheat-rice rotation. There was no trend in yields in response to treatment with time.