Masakazu Tani

Groundwater–soil–crop relationship with respect to arsenic contamination in farming villages of Bangladesh – A preliminary study

To clarify the groundwater-soil-crop relationship with respect to arsenic (As) contamination, As concentration was measured in tubewell (TW) water, surface soil from farmyards and paddy fields, and fresh taro (Colocasia esculenta) leaves from farmyards in the farming villages of Bangladesh. The As concentration in TW water from farmyards was at least four times higher than the Bangladesh drinking water standard, and the concentration in fresh taro leaves was equal to or higher than those reported previously for leafy vegetables in Bangladesh. As concentration of surface soils in both farmyards and paddy fields was positively correlated with that of the TW water. Further, the concentration in surface soil was positively correlated with levels in fresh taro leaves in the farmyard. This study, therefore, clarified the groundwater-soil-crop relationship in farmyards and the relationship between groundwater-soil in paddy fields to assess the extent of As contamination in Bangladeshi villages.

Variation in Arsenic Concentration Relative to Ammonium Nitrogen and Oxidation Reduction Potential in Surface and Groundwater

Abstract Arsenic (As), ammonium‐nitrogen (N), nitrate‐N concentrations, and oxidation–reduction potential (ORP) in the water samples from the river, pond, dug well, and shallow and deep tube wells (TW) were investigated in a farming village of southwestern Bangladesh. Concentrations of As and ammonium‐N were the highest, whereas ORP was the lowest in the shallow TW water among the water sources. The ammonium‐N concentration correlated positively with the As concentration and negatively with ORP for all samples, irrespective of the water sources. A rise in the ammonium‐N concentration was hypothesized to enhance microbial activity, which in turn would lower ORP, and then As was released from sediments to the surrounding water in a reducing condition. The source of ammonium‐N in the shallow TW water was identified as N fertilizer, based on the δ15N analysis. Thus, the influence of N fertilizer application on As contamination in groundwater was suggested.

Does actor power impede outcomes in participatory agroforestry approach? Evidence from Sal forests area, Bangladesh

Over the last two decades, participatory forestry practices have gained a remarkable shift from top down traditional forest management to more people-oriented approaches in Bangladesh. The new approaches have involved many actors; however, their relative role or actor power has not been investigated thoroughly. Hence, the study was undertaken to identify the relative role of actors in participatory agroforestry program (PAP) and assess how the interests of powerful actors influence the social, economic and ecological outcomes of PAP. Using different quantitative and qualitative data collection techniques, the study identified twenty actors, representing a diversity of interests in PAP in Madhupur Sal forests area. The actors’ power analysis suggested that the forest department evidenced itself as the most powerful and influential actor in every dimensions of power. The study argues that PAP has no doubt led a new elucidation of forest management with a strategy to include local people so as to improve Sal forests condition and livelihoods of local communities. At the same time, exercising of power especially from the powerful actors has strictly controlled the empowerment and access of local people, and apparently reduced the participants’ opportunities to maximize outcomes of PAP. So, there is an immediate need to empower local participants, by which they can easily play the central role in decision making and governing all of their development activities.

Deforestation in the Teknaf Peninsula of Bangladesh: A study of political ecology

This volume presents studies on deforestation in the Teknaf Peninsula in Bangladesh. The studies analyze the mechanisms and causes of deforestation and explore possible methods of reforestation. The peninsula once had rich forests that harbored a variety of wildlife, including large mammals such as wild boars, deer, and Asian elephants. However, deforestation, which has advanced across the peninsula, has become a critical issue. Currently, clusters of trees in this area are only found in patches of tree plantations and “social” forest plots. Natural forests harbor a very small number of trees, and most areas defined as forests are actually covered only with shrubs and bushes. Although young trees are evidence of regrowth, forests do not appear to be regenerating.

Forest dwellers and encroachers in Teknaf

This chapter begins by providing an overview of the population distribution within as well as outside of the restricted forest area in the study region. Next, it presents the findings of a case study on the socioeconomic attributes and activities of residents by ethnic groups in a village consisting of settlements within and outside of the Teknaf Wildlife Sanctuary. Although reserved forests are legally closed to private activities, with the exception of those of certain categories of people who have special rights to live in the area, about half of these forest dwellers are “illegal” encroachers. Whereas Bengalis, who legally reside within the reserved forest area, earn comparable incomes to those of people living outside of the reserved forest area, the incomes of encroachers and minority ethnic groups are significantly lower. Many of the encroachers moved relatively recently into this restricted area, and the inflow of settlers does not appear to be lessening. Because the encroachers’ primary means of subsistence entails farming that requires the clearing of existing forests, the increase in their numbers appears to constitute a major threat to forest regeneration in this area.

Impact of betel leaf cultivation on forests

The betel is a major cash crop on the Teknaf Peninsula. The cultivation of betel plants affects forests in two ways. The construction of “pan boroj,” a facility to provide the plants with shading, consumes a large amount of forest resources every year. Another way of betel cultivation’s influence on forests is tree clearance in cultivation plots. Pan boroj tend to be constructed on gentle slopes where forests originally existed because more productive and limited flatlands are used for other crops such as rice. Trees are cleared to make room for a pan boroj, and as long as betel is cultivated, trees will not regrow at that spot. This study conducted village household surveys to record all pan boroj in a village and to quantitatively assess the impact of betel cultivation on the nearby forests. An estimate of forest resource use is equivalent to approximately 5% of biomass annually generated in the village area. Cultivation plots of betel plans also account for another 5% of the area. Despite the negative impacts of betel cultivation on forests, this study also finds the economic importance of betel cultivation in the village economy, and estimates that betel cultivation may compensate the lack of sufficient livelihood generated by rice cultivation in limited flat land.

Physiography, Forests, and People in Teknaf

The Teknaf peninsula, which is located in the farthest southeastern corner of Bangladesh, has a diversified physiography exhibiting hills, piedmont plains, tidal floodplains, and beaches. The climate is subtropical, with temperatures ranging seasonally from 15 °C during the winter to 33 °C during the summer and very heavy rainfall (about 4000 mm). The peninsula, which experiences frequent cyclones, is vulnerable to climate change. More than 30% of the area consists of forests that are highly degraded as a result of various human activities as well as climate change such as frequent cyclone. Poverty is one of the major issues in the peninsula, with approximately 38% of the population living below the poverty line. Livelihoods center on agriculture, forest-related activities, and collection of marine resources. Although human settlements have existed in this area from ancient times, after 1990, extensive settlement has occurred in and around the forests. Apart from Bengalis, other ethnic groups living in the peninsula include the Chakma, Rakhine, and Rohingya groups.

Remote sensing characterization of changes in forest resources and betel leaf cultivation through time

Obtaining accurate data for monitoring the conditions of resources in developing countries is typically challenging. The reason may be insufficient facilities or, in some cases, disorganization of authorities. These difficulties also apply to procuring data on forest resources in Teknaf. There have been some recent initiatives and/or activities to conserve forests in this area. However, recent data are inadequate for determining the underlying mechanism of deforestation in Teknaf. What is required is time series data for the period before the onset of deforestation. Remote sensing offers a powerful tool for conducting a quantitative analysis of a time series and/or seasonal changes in forest resources. In this chapter, we discuss how we used remote sensing data to show changes in Teknaf’s forest resources and assess changes in betel leaf cultivation practices among villagers by combining an analysis of remote sensing data with an analysis of the livelihood status of inhabitants of the village of Marishbunia.

Analysis of Power Dynamics and Livelihood Assets in Participatory Forest Management: Experience from Bangladesh

Participatory forestry (PF) plays a significant role to involve local communities and different actors in resources management and livelihood improvements. However, the power of important actors to misuse the PF for their self-interest has been stated as a key obstacle to success. Hence, this study seeks to identify the most powerful actors and the extent to which they affect PF decision- making and also to measure and evaluate the livelihood assets of participants. Empirical data were collected from Madhupur and Teknaf PF sites of Bangladesh during the different time intervals. The actors’ power analysis found out that the forest administration evidenced itself as the most powerful and influential actors in PF. In the case of livelihood analysis, the overall results indicated that the total value of PF members’ livelihood assets were 0.82 and 0.75 for Madhupur and Teknaf study sites. Livelihood asset conditions were significantly different between the PF members’ and non-members’ (0.65 and 0.62 for non-members’). However, the development of social and financial assets did not reveal a notable increase considering natural, physical and human assets. Therefore, it is very important to pay more attention to accelerate social and financial assets through intensive training, establishing conflicts resolution mechanism and adopting proper tree-crop technologies, and also provide alternative livelihood approaches to the forest dependent people. In addition, there is an immediate need to empower local PF members, by which the general members play the central role in decision making and governing all of their development activities.