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Rambutan cultivation techniques

Novel shaker bottle cultivation method for the long spined sea urchin (Diadema antillarum; Philippi, 1845) results in high larval survival and settlement rates

The long spined sea urchin Diadema antillarum was an abundant grazer on Caribbean coral reefs, until 1983–1984, when densities were reduced by ∼98% during a region wide die-off. Since then, there has been very little natural recovery of the species and interest is growing in applying aquaculture as a tool for population enhancement. In this study we optimized a new shaker bottle cultivation method for D. antillarum. The method was tested in a series of experiments by culturing D. antillarum from egg to juvenile in the Netherlands as well as the USA. Larvae were cultured in standard 1-L glass reagent bottles, suspended by gentle constant movement on an orbital shaking table and fed with either the microalgae Rhodomonas lens or Rhodomonas salina. Effects on larval growth and survival were evaluated for different microalgal feeding concentrations, larval densities, and culture temperatures. Larval density and growth were measured twice a week over a period of up to 56 days. Larvae grew significantly faster on a higher feeding concentration up to 90,000 Rhodomonas sp. cells mL−1, twice weekly, compared to 30,000 and 60,000 cells mL−1. A density of 1 larvae mL−1 resulted in the highest body size and survival compared to densities of 2 or 4 larvae mL−1. Overall survival from larva to settled juvenile urchin increased from 8 to 10% settlement to 32–33% when the initial density was lowered further from 1.2 to 0.4 larvae mL−1. Growth, survival, competency and settlement did not differ between larval cultures kept at 25 °C or 28 °C. We believe that this novel method for culturing D. antillarum larvae, once scaled-up and validated to pilot scale, could provide juveniles for restocking of urchin-depleted reefs that suffer from algae overgrowth.

Developing Strategic Communication Strategies for Cultivating Communities of Practice

This paper lays the groundwork for building a communication model that will help cultivate communities of practice through the use of strategic communications. Theoretical models describing communities of practice in organizational knowledge generation typically have three main actors; the individual, the community and the organization. These models usually mention the necessity for their interaction, but are never specific about how this should be done. Furthermore, there has been little research on how communication processes can affect the relationship between the three actors in the model. This paper proposes that the interaction between the community, the individual members of the community and the organization must be facilitated and promoted through specific strategic communications in order to guarantee the success of the community. Topics such as knowledge sharing, knowledge building and organizational learning are looked at through a communication perspective.

A cross-national exploration of shadow education use by high and low SES families.

Worldwide, an increasing number of students seek private supplementary tutoring, known as ‘shadow education.’ Various studies report social class differences in the use of shadow education. High-SES families may invest in shadow education as a form of concerted cultivation, seeking to improve their children’s school achievement. In this study, we apply meta-analytic structural equation modeling to explore relationships between parental education, income, and the use of shadow education across nations and educational contexts. We find robust relationships between parental education, income and the use of shadow education. Moreover, we assess a mediating role of shadow education in the relationship between SES and achievement. Shadow education appears to fulfill a competitive function for privileged families who seek to secure advantage in educational competition. We conclude that educational research, particularly research concerned with inequality of opportunities, needs to take account of the progressively prominent position of shadow education in the educational landscape.

An ecosystem services analysis of oil palm and alternative land use systems on peat in Malaysia

In this article, we assess the potential of alternative land use systems using non-drainage peatland species which could eventually phase out or partly replace oil palm plantations on undrainable peatlands. We have used the ecosystem services approach to analyse what scenarios using drainage-free peatland species could be suitable alternatives for oil palm cultivation on peat and how these scenarios compare to oil palm plantations in terms of selected ecosystem services. Our results indicate that alternative paludiculture systems will provide more direct and indirect ecosystem services than oil palm plantations on peat. We also found that stakeholders were aware of issues with growing oil palm on peat, and that there was a general intention for sustainable use of peatlands amongst several groups of stakeholders. Replacing oil palm with alternative systems such as paludiculture in Malaysia is not yet realistic. The most important impediments are a lack of knowledge on potential of non-drainage peatland species and its associated value chains, as well as the technical difficulty for smallholders to implement such a system. We recommend starting experimental plantings with paludiculture systems to further test species performance, life cycle analysis, growth, intercropping limitations and possibilities, yields and improvements in the value chain.

Mechanisms for sustainable use of biodiversity in and beyond natural ecosystems

The increasing demand for Prunus africana resources is an opportunity for its conservation and commercial use to support livelihoods in Africa. The objective for this study was to investigate major steps to advance production of P. africana for long-term commercial use in Uganda. Specific objectives were to explore potential production schemes, setbacks in production and strategies to advance it. The study was done by review of literature, documents and interviews with experts. Results indicated Agroforestry and large plantations to be useful schemes for production. Identified setbacks are: low trade in P. africana, unknown returns from production, competing land uses, long growth period, limited market assurance and information. The lack of a resource assessment for P. africana in forests contributes to its low trade which undermines related economic benefits for national development and incentives to commercial production. We propose that a national Quantitative resource assessment of P. africana in forests is one of the crucial steps that should be undertaken to carefully organise and advance sustainable trade to provide rational incentives for commercial production. Subsequently, production should be localised in suitable sites and producers be organised into cooperatives. Further research to improve returns from commercial production of P. africana is needed.