Impact of Eucalyptus gall wasp, Leptocybe invasa infestation on growth and biomass production of Eucalyptus grandis and E. saligna seedlings in Tanzania

9pA study was carried out to determine the impact of Leptocybe invasa infestation on growth and biomass production of Eucalyptus grandis W. Hill ex Maiden and E. saligna Smith seedlings in Tanzania. Three- month old seedlings were infested with L. invasa. Twenty two weeks post infestation, heights of infested E. grandis seedlings were reduced by 39.6%, while diameters were reduced by 11.3% compared to uninfested seedlings. On the other hand, the heights of infested E. saligna seedlings were reduced by 38.2% and diameters were reduced 7.7% compared to uninfested seedlings. Dry weight biomass reduction of infested seedlings was significantly higher on stem and leaves than roots and branches of both E. grandis and E. saligna. The impact of L. invasa infestation on growth and biomass production was higher in E. grandis than E. saligna. Prevention and control of L. invasa infestation should be given priority. Similar future trials should examine other commercially grown Eucalyptus species in Tanzania

Impact of Eucalyptus gall wasp, Leptocybe invasa infestation on growth and biomass production of Eucalyptus grandis and E. saligna seedlings in Tanzania

9pA study was carried out to determine the impact of Leptocybe invasa infestation on growth and biomass production of Eucalyptus grandis W. Hill ex Maiden and E. saligna Smith seedlings in Tanzania. Three- month old seedlings were infested with L. invasa. Twenty two weeks post infestation, heights of infested E. grandis seedlings were reduced by 39.6%, while diameters were reduced by 11.3% compared to uninfested seedlings. On the other hand, the heights of infested E. saligna seedlings were reduced by 38.2% and diameters were reduced 7.7% compared to uninfested seedlings. Dry weight biomass reduction of infested seedlings was significantly higher on stem and leaves than roots and branches of both E. grandis and E. saligna. The impact of L. invasa infestation on growth and biomass production was higher in E. grandis than E. saligna. Prevention and control of L. invasa infestation should be given priority. Similar future trials should examine other commercially grown Eucalyptus species in Tanzania

The current and future value of nature-based tourism in the Eastern Arc Mountains of Tanzania

The financial benefit derived from nature-based tourism in the Eastern Arc Mountains (EAMs) of Tanzania has never been assessed. Here, we calculate the producer surplus (PS) related to expenditure on accommodation in the EAMs. This estimate is based on the number of visitor bed-nights collected from a representative sample of hotels, coupled with spatially explicit regression models to extrapolate visitor numbers to unsampled locations, and adjusted to account for how far visits were motivated by nature. The estimated annual PS of nature-based tourism is ~US$195,000. In order to evaluate the future impact of different forest management regimes on PS over a 25 year period, we compare two alternative scenarios of land use. Under a 'hopeful expectations' scenario of no forest loss from protected areas, the present value of PS from nature-based tourism is ~US$1.9 million, compared with US$1.6 million under a 'business-as-usual' scenario. Although the value of nature-based tourism to the EAMs is lower than that generated by Tanzania[U+05F3]s large game reserves, these revenues, together with other ecosystem services provided by the area, such as carbon storage and water regulation, may enhance the case for sustainable forest management

Measuring, modeling and mapping ecosystem services in the Eastern Arc Mountains of Tanzania

In light of the significance that ecosystem service research is likely to play in linking conservation activities and human welfare, systematic approaches to measuring, modeling and mapping ecosystem services (and their value to society) are sorely needed. In this paper we outline one such approach, which we developed in order to understand the links between the functioning of the ecosystems of Tanzania’s Eastern Arc Mountains and their impact on human welfare at local, regional and global scales. The essence of our approach is the creation of a series of maps created using field-based or remotely sourced data, data-driven models, and socio-economic scenarios coupled with rule-based assumptions. Here we describe the construction of this spatial information and how it can help to shed light on the complex relationships between ecological and social systems. There are obvious difficulties in operationalizing this approach, but by highlighting those which we have encountered in our own case-study work, we have also been able to suggest some routes to overcoming these impediment