Resilience to natural hazards: How useful is this concept?

Resilience is widely seen as a desirable system property in environmental management. This paper explores the concept of resilience to natural hazards, using weather-related hazards in coastal megacities as an example. The paper draws on the wide literature on megacities, coastal hazards, hazard risk reduction strategies, and resilience within environmental management. Some analysts define resilience as a system attribute, whilst others use it as an umbrella concept for a range of system attributes deemed desirable. These umbrella concepts have not been made operational to support planning or management. It is recommended that resilience only be used in a restricted sense to describe specific system attributes concerning (i) the amount of disturbance a system can absorb and still remain within the same state or domain of attraction and (ii) the degree to which the system is capable of self-organisation. The concept of adaptive capacity, which has emerged in the context of climate change, can then be adopted as the umbrella concept, where resilience will be one factor influencing adaptive capacity. This improvement to conceptual clarity would foster much-needed communication between the natural hazards and the climate change communities and, more importantly, offers greater potential in application, especially when attempting to move away from disaster recovery to hazard prediction, disaster prevention, and preparedness.     

Climate change impact and potential adaptation strategies under alternate climate scenarios for yam production in the sub-humid savannah zone of West Africa

Globally, yam (Dioscorea spp.) is the fifth most important root crop after sweet potatoes (Ipomoea batatas L.) and the second most important crop in Africa in terms of production after cassava (Manihot esculenta L.) and has long been vital to food security in sub-Saharan Africa (SSA). Climate change is expected to have its most severe impact on crops in food insecure regions, yet very little is known about impact of climate change on yam productivity. Therefore, we try estimating the effect of climate change on the yam (variety: Florido) yield and evaluating different adaptation strategies to mitigate its effect. Three regional climate models REgional MOdel (REMO), Swedish Meteorological and Hydrological Institute Regional Climate Model (SMHIRCA), and Hadley Regional Model (HADRM3P) were coupled to a crop growth simulation model namely Environmental Policy Integrated Climate (EPIC) version 3060 to simulate current and future yam yields in the Upper Ouémé basin (Benin Republic). For the future, substantial yield decreases were estimated varying according to the climate scenario. We explored the advantages of specific adaptation strategies suggesting that changing sowing date may be ineffective in counteracting adverse climatic effects. Late maturing cultivars could be effective in offsetting the adverse impacts. Whereas, by coupling irrigation and fertilizer application with late maturing cultivars, highest increase in the yam productivity could be realized which accounted up to 49 % depending upon the projection of the scenarios analyzed.     

Density and nutritional condition of carabid beetles in wildflower areas of different age

Density and nutritional condition of the five carabid beetle species Agonum mülleri, Anchomenus dorsalis, Anisodactylus binotatus, Pterostichus vernalis and Poecilus cupreus was studied. Carabids were caught in sixteen 1–4-year-old wildflower areas, identified and counted, their nutritional condition was calculated and calculations were related to habitat parameters (i.e. wildflower area age, vegetation cover, soil water content, habitat size, surrounding landscape composition) and sex.Whereas the number of Anisodactylus binotatus caught responded positively to succession in wildflower areas, A. mülleri numbers tended to decrease and the other three species were unaffected. In a stepwise multiple regression species affiliation, sex and age of wildflower area explained together 98.5% of the variance in the pooled nutritional condition of Anchomenus dorsalis, Anisodactylus binotatus, A. mülleri and P. vernalis. Age of wildflower area alone explained 61.7% of the variance and age increased the nutritional condition of carabids. Correspondingly, nutritional condition of Poecilus cupreus was positively correlated with the age of wildflower area. Overall, the nutritional condition of the carabid assemblage studied increased from the first to the second year and then remained stable. To keep the proportion of 1-year-old wildflower areas low, wildflower areas should therefore be maintained for several years to improve the life conditions of carabid beetles and to enhance their beneficial effects in agroecosystems.