Gliricidia sepium Carbon Inputs and Soil Carbon Pools in a Costa Rican Alley Cropping System

Alternative land management practices, including agroforestry, help to maintain levels of soil organic matter (SOM) and can facilitate soil carbon (C) sequestration for mitigating atmospheric CO₂ emissions. This study quantified C inputs and determined the changes of the soil C pool in a 19-year-old Gliricidia sepium alley cropping system, studied at two fertiliser levels (tree prunings only [? N], and tree prunings plus chicken manure [+ N]), and was compared to a sole crop system. Carbon input from tree prunings ranged from 455 to 457 g C m^{? 2} y^{? 1}, whereas C inputs from crop residues were similar between alley- and sole crops ranging from 121 to 159 g C m^{? 2}y^{? 1}. The soil organic C (SOC) pool in the alley crop was 16–23% higher than the sole crop. In the 19th year of alley farming, SOC was significantly higher (p < 0.05) in the alley crop (3.2%) compared to the sole crop (2.4%), and was also greater compared to that at the time of establishment of the agroforestry system (2.8%). Gross SOC turnover to a 20-cm depth ranged from 12 to 14 years in the + N and ?N alley crops compared to 49 and 50 years in the + N and ?N treatments for the sole crops. Residue stabilisation efficiency in the alley crops was 39% and 55% in + N and ?N treatments respectively.     

Success in social marketing

In a series of articles, Philip Kotler, first with Sidney Levy [11], then with Gerald Zaltman [12], and then singularly [8], has significantly broadened the scope of marketing management. Marketing strategy, according to Kotler, is pertinent in numerous areas in addition to its business application. This article is concerned with one particular area for the expanding application of the marketing concept— social marketing.The use of marketing strategy to achieve social objectives produces both similarities and differences to business applications. Comparing these similarities and differences should produce some insight about the potential success of social marketing.     

Promoting farm/non‐farm linkages for employment of the poor in South Africa: A research agenda focused on small‐scale farms and agroindustry

This article presents a policy research agenda for the promotion of farm/non‐farm linkages in South Africa. Our premise is that promoting the participation of small farms and small agroindustrial businesses in these linkages will have a strong impact on employment and income for the poor. We argue that there is potential for growth in linkages. The first question of the policy research agenda concerns the current status of linkages, and we note the dearth of research on this. The second question concerns the constraints on and prospects for promoting linkages from the demand side, and the third question treats the same concerns from the supply side. The fourth question is rooted in the duality in South Africa's non‐farm and farm sectors, and asks whether, and how, small and large agroindustrial businesses and farms will compete or relate in ‘business linkages’ that can benefit intersectoral linkages. The final question concerns the impacts of and alternatives for policies and programmes to spur linkages.     

Technical Progress and Product Reliability under Competition and Monopoly

Technical progress lowers costs and prices but appears to have an ambiguous effect on product reliability. This paper presents a simple model which explains this observation. Copyright © 2013 John Wiley & Sons, Ltd.     

On (Not) Closing the Gaps: The Evolution of National and Regional Unemployment Rates by Race and Ethnicity

This paper conducts stationarity tests for levels and ratios of national and regional unemployment rates by race and ethnicity. Results indicate that both unemployment rates and ratios for the total population and for subgroups by race, ethnicity and region are stationary around changing means. The black/white unemployment ratio has increased on average and the Hispanic/white unemployment ratio has decreased on average. Results are compared across regions of the US.