4 research outputs found
The Security imaginary: Explaining military isomorphism
This article proposes the notion of a security imaginary as a heuristic
tool for exploring military isomorphism (the phenomenon that
weapons and military strategies begin to look the same across the
world) at a time when the US model of defence transformation is
being adopted by an increasing number of countries. Built on a critical
constructivist foundation, the security-imaginary approach is contrasted
with rationalist and neo-institutionalist ways of explaining
military diffusion and emulation. Merging cultural and constructivist
themes, the article offers a ‘strong cultural’ argument to explain why a
country would emulate a foreign military model and how this model is
constituted in and comes to constitute a society’s security imaginary.Web of Scienc
The contributions of biological control to reduced plant size and biomass of water hyacinth populations
Water hyacinth is invasive in many countries, where it reduces aquatic biodiversity and limits water resource utilisation. Biological control of water hyacinth has been successful in South Africa, but has suffered from a lack of empirical data to prove causation. Insect exclusion trials were conducted to quantify the contribution of Neochetina eichhorniae and N. bruchi to the integrated control of water hyacinth on the Nseleni River, South Africa. Insecticide was not expected to induce phytotoxicity, but would prevent weevil damage in water hyacinth plants; and weevil herbivory was predicted to reduce plant petiole length, and above/below surface biomass. Results showed that insecticide had no phytotoxic effects and excluded weevils for 3 weeks, providing a baseline for field applications. Biological control on the Nseleni River directly affected water hyacinth biomass and petiole length, but did not affect plant cover. Plants subject to weevil herbivory demonstrated reductions in above and below surface biomass and had shorter petioles compared to insect-free plants. Dead biomass was also higher in biological control treatments. Biological control strongly affects plant size, biomass and vigour; however, further integrated control is required to facilitate reduction in mat cover, which is the goalpost for successful control of floating aquatic plants