Asset adaptation and urban food security in a changing climate: a case study of Kalingalinga and Linda Compounds in Lusaka, Zambia: Danny Simatele (original) (raw)
Related papers
Seymour & Veldtman 2010 Austral Ecology.pdf
Biological control agents used to manage alien vegetation are generally viewed as providing an ecosystem service, owing to reduced ecological and economic costs of invasion following their release. In particular, gall-formers are popular as biological control agents because they are host-specific and therefore considered low risk. However, galls can also be considered to be ecological engineers, because they provide nutritional resources for native invertebrates. We tested whether native invertebrates had formed associations with the gall-forming fungus Uromycladium tepperianum, introduced into South Africa to control the Australian invasive alien tree Acacia saligna, by collecting U. tepperianum galls and monitoring emergence. We found that a number of invertebrates had formed associations with the biological control agent, among which was the important citrus pest, Thaumatotibia leucotreta (false codling moth). We used pheromone-baited traps to ascertain if this supplementary source of T. leucotreta increased their abundance in orchards close to patches of gall host, but did not find this to be the case. We did find, however, that control measures used by farmers explained T. leucotreta abundances in traps, which may have obscured detection of any effects of a nearby host for the pest. Nevertheless, this study illustrates the first case of a host-specific classical biological control agent providing resources for an economically significant crop pest.We conclude that although biological control agents are strictly vetted to ensure host-specificity, introduced biological control agents that become abundant and can act as ecological engineers pose risks when native biota form associations with them, resulting in a number of possible cascading ecosystem effects. In addition, there could be economic consequences when these associated species include agricultural pests. We conclude that not just host specificity, but potential ecological effects of biological control agents, should be considered in their selection.
A preliminary treatment of the Central American species of Octoblepharum (Musci: Calymperaceae)
Bryophyte Diversity and Evolution, 1991
The species of Octoblepharum occurring in Central America have been critically examined. Six are recognized as valid species: O. albidum, O. cocuiense, O. cylindricum, O. erectifolium, O. pulvinatum and O. stramineum. Synonyms are given for these species: O. longifolium = O. albidum; O. mittenii, O. fragillimum, O. pellucidum and =O. pulvinatum var. angustifolium are synonyms of O. cocuiense; O. juruense and O. densum = O. pulvinatum and O. purpureo-brunneum = O. stramineum. All species are widely distributed in the area except for O. cylindricum and O. stramineum that are known only from Belize and Panama respectively.
Octoblepharum peristomiruptum (Octoblepharaceae) a new species from the Neotropics
2020
Octoblepharum peristomiruptum, a new species of moss in the family Octoblepharaceae from Panama and Brazil, is described and illustrated. The new species is characterised by plants with a reddish-purple colour particularly at the leaf bases, peristomes of eight teeth, each tooth composed of two rows of cells, fenestrate and usually completely separated at the base, strongly vertically striate-reticulate, some striations forked-like in shape. At the base of the teeth, some striations are horizontally orientated, poorly developed or absent, particularly on the cell wall that is rupturing in the separation of the vertical rows of the cells that form each tooth.
Parasitic plants in southwestern Australia
The southwestern Australian flora is unique in the world, not only for its biodiversity and endemism, but also for its functional biodiversity. It also contains the world's most nutrient-impoverished soils, has a prolonged-summer period and the vegetation is extremely fire-prone. These conditions have engendered an array of survival adaptations that have evolved in these harsh conditions across a diverse range of species. It is well recognised that the southwest flora has the toughest and most spiny vegetation of the world, the greatest number of species that store their seeds in woody fruits, and the most specialised means of obtaining limited soil nutrients and water. This book focuses on the survival mechanisms, adaptations and ecology of the unique Southwest Australian flora (restricted here to flowering plants). The book begins with an examination of how the flora has evolved into the present forms. It describes further in detail the adaptive responses of the flora to the m...
Quambalaria species associated with plantation and native eucalypts in Australia
Plant Pathology, 2008
This study aimed to determine which species of Quambalaria are associated with shoot blight symptoms on Corymbia spp. An additional aim was to determine the presence and impact of quambalaria shoot blight on Eucalyptus species used in plantation development in subtropical and tropical regions of eastern Australia. Surveys identified three Quambalaria spp. -Q. pitereka , Q. eucalypti and Q. cyanescens -from native and plantation eucalypts, as well as amenity plantings, including the first confirmed report of Q. eucalypti from Eucalyptus plantations in Australia. Symptom descriptions and morphological studies were coupled with phylogenetic studies using ITS rDNA sequence data. Quambalaria pitereka was the causal agent of blight symptoms on species and hybrids in the Corymbia complex. Quambalaria eucalypti was identified from Eucalyptus species and a single Corymbia hybrid. Quambalaria cyanescens was detected from native and plantation Corymbia spp.
Australasian Plant Pathology
Neofusicoccum australe is a class III endophyte characterised by a quiescent passive life phase and an active pathogenic life phase as a latent pathogen. The latter life stage has been observed worldwide for numerous woody horticultural hosts. In this study, we have re-evaluated GenBank ITSrDNA sequence data to establish the current host and geographical range of N. australe. Additionally, we have interrogated the diversity of N. australe in Australia using microsatellite markers to ascertain if there are any host or site preference for different genotypes. N. australe has a widespread distribution across ten countries and colonises 46 hosts from 18 plant families; mainly angiosperms, some coniferous species and one monocot. Phylogenetic analysis of the ITSrDNA sequence indicates there is a single dominant ITS genotype present in most locations and there are another 12 rare or moderately rare genotypes. Populations of N. australe in Australia appear to be highly diverse, and there is no discernable host or habitat restriction. The dominance of N. australe in native forest throughout the southwest of Western Australia, and its rarity elsewhere in native vegetation, while being common as a pathogen of horticultural hosts, suggests that this species is endemic to Western Australia.
Polyphagy in an uncertain environment: Helicoverpa punctigera in inland Australia
Austral Ecology, 2016
We investigated potential primary hosts for Helicoverpa punctigera, a polyphagous lepidopteran pest which affects many crops, but also has many native hosts in non-cropping regions of inland Australia. The most common hosts are Asteraceae and Fabaceae, but there is little information on the relative importance of different species in these families for the population dynamics of H. punctigera in the inland. We tested three common hosts, one legume (Cullen cinereum) and two daisies, Rhodanthe floribunda and Polycalymma stuartii, for their suitability for survival and growth of early instar larvae. Survival was high on the flowers of all three species, and on the leaves of C. cinereum and R. floribunda, but low on leaves of P. stuartii. There were significant differences in growth rates, measured by head widths, in the order of C. cinereum > R. floribunda > P. stuartii, and flowers > leaves. They were strongly correlated with nitrogen content, measured by fresh weight. Field surveys of larval populations in western Queensland indicated that two legume species, C. cinereum and Cullen pallidum, were widely utilized and supported many larvae. Daisies were generally less widely used and/or had lower numbers of larvae. When C. cinereum or C. pallidum was found near daisies, the legume had more larvae if both the daisy and the legume were flowering, but this was reversed if only the daisy was flowering. The seasonality and habitats of the daisies and legumes are different. C. cinereum and C. pallidum (a new host record for H. punctigera) may be primary hosts of H. punctigera in inland Australia and key hosts for maintaining populations in flood plains. However the areas occupied by daisies can be more extensive depending on rainfall, and some species may be critical in generating outbreaks that affect cropping areas in southeast Australia.
Shackleton et al 2016 C. odorata paper, Biological Invasions.pdf
Invasive alien plant species such as Chromolaena odorata have negative impacts on biodiversity, ecosystem services and human well-being. Ecological impacts of this shrub are relatively well understood, but its impacts on local livelihoods and perceptions are poorly documented. We mapped C. odorata distribution in eastern Africa (Ethiopia, Kenya, Rwanda, Tanzania and Uganda) and compared perceptions and quantified the impacts of this species across Tanzanian villages with varying degrees of invasion density. Data were collected through 240 household questionnaires. Results indicate that C. odorata is a relatively new invader that already has severe negative impacts and is threatening livelihoods and the environment. Impacts include reductions in native biodiversity and the amount of available forage for livestock, reduced crop and water yields, and impaired mobility. Continued spread will cause additional negative impacts on poor rural communities. Implementation of a biological control programme targeting C. odorata is needed as a cost effective management approach along with other control and restoration measures.