PhD fellow, Bangladesh Agricultural University
Collection and conservation of threatened plants of Bangladesh
Bangladesh is a small country with very rich plants diversity but information is often guess works or based on secondary information. Aim of my research is conduct field survey in reserve forests of Bangladesh to know the plants status (exist or not, if exist how many of them, where), said to be threatened in natural condition. As soon as we spotted the threatened species we will collect the live specimens, fertile materials for conservation and creating gene pool for further research.
Abstract: Homegardens are traditional food systems that have been adapted over generations to fit local cultural and ecological conditions. They provide a year-round diversity of nutritious foods for smallholder farming communities in many regions of the tropics and subtropics. In southwestern Uganda, homegardens are the primary source of food, providing a diverse diet for rural marginalized poor. However, national agricultural development plans as well as economic and social pressures threaten the functioning of these homegardens. The implications of these threats are difficult to evaluate, because the structure and functions of the homegardens are not well understood. The aim of the study was to identify patterns and influencing factors in the diversity of homegardens by documenting the floristic diversity and its interactions with spatial, environmental and socio-economic factors. A geographically and socially focused assessment of floristic diversity in 102 randomly selected homegardens in three districts of southwest Uganda was conducted along a deforestation gradient following a human ecology conceptual framework and testing multiple quantitative hypotheses regarding the above mentioned factors. A merged mixed-method approach was followed to provide context and feedback regarding quantitative findings. Results show a high total richness of 209 (mean 26.8 per homegarden) crop species (excluding weeds and ornamentals) dominated by food species, which constituted 96 percent of individuals and 44 percent of all species. Forest-edge homegardens maintained higher plant diversity compared to homegardens in deforested areas and near degraded wetlands. Multiple linear regression models indicated elevation, location, homegarden size, distance to market, additional land ownership (outside the homegarden) and livestock ownership as significant predictors of crop diversity. Cluster analysis of species densities revealed four garden types: ‘diverse tree gardens’, ‘small forest-edge gardens’, ‘large, old, species-rich gardens’, and ‘large, annual-dominated herb gardens’, with 98% correct classification. Location, elevation, and garden size were also important determinants in the cluster assignment. We conclude that the diversity of the studied homegardens may be changing as part of adaptive traditional practices and in response to external drivers. The identified patterns illustrate the importance of homegardens for rural livelihoods and may offer some ways to support farmers to maintain these systems as relevant mechanisms for development in Uganda.
Pub.: 01 Jun '18, Pinned: 09 May '18
Abstract: Publication date: May 2018 Source:Urban Forestry & Urban Greening, Volume 32 Author(s): Madhumitha Jaganmohan, Lionel Sujay Vailshery, Seema Mundoli, Harini Nagendra Urban green spaces provide critical social and ecological support for cities, but we know little about their diversity and composition in cities of the Global South. This is especially true of lesser known urban spaces such as sacred sites, which are of important cultural and biodiversity significance. We examine tree diversity and composition in sacred sites in Bengaluru, one of India’s fastest growing cities. We recorded 5504 trees from 93 species across 62 temples, churches, and Hindu, Christian and Muslim cemeteries in central areas of Bengaluru. Over half (52%) of the tree species were of native origin, a much higher proportion when compared to other green spaces in the city such as parks. Tree density in sacred sites was much higher than that in parks and informal settlements in Bengaluru. Temples and Hindu cemeteries contained the highest proportion of native species, with large numbers of Ficus benghalensis, a keystone sacred species. Trees in sacred spaces provide an important buffer against urban environmental stress in Indian cities, and serve as refuges for urban wildlife and biodiversity. We need greater information on these lesser known, but culturally significant alternate spaces. They play an important, though ignored role in the environmental sustainability of rapidly growing cities in the Global South.
Pub.: 25 Apr '18, Pinned: 09 May '18
Abstract: Background and aims Tree species effects on biogeochemical cycles are well studied, but the interactive effects of tree species in mixtures remain poorly understood. We studied how tree species identity and species diversity affect nutrient cycling in mature forests. Methods In a Belgian platform of 53 forest plots varying in tree species diversity and composition, we sampled the return of carbon, nitrogen and base cations via leaf litterfall and their stocks in the forest floor and topsoil. Results Tree species identity effects were clear; diversity effects were weak or absent. The leaf litter input from shrub species depended on the composition of the tree canopy and had a higher quality than the litter of the trees. Monocultures of pedunculate oak had the highest input of litter from shrub species; in mixtures with beech, however, this input was disproportionally low. Conclusions We found indirect effects of tree species diversity on nutrient cycling, via effects of the tree species composition on the abundance and composition of the shrub layer. This is particularly important in forests consisting of tree species with low leaf litter quality, because nutrient cycling may benefit from the presence of shrub species with higher leaf litter quality.
Pub.: 23 Apr '18, Pinned: 09 May '18