Trends in Benzo(a)Pyrene, 1966–77

The advent of stringent regulation of the storage of liquids in underground containers presents a new dimension to an operating practice long taken for granted. Previously, tanks went underground to provide a safe and convenient method for handling.liquids. Unfortunately, the environmental impact of leakage from those containers was not anticipated, nor were tank designs properly configured to minimize the threat. As local officials became alert to the potential for damage, public pressure forced tank owners to rethink this casual practice. Manufacturers and suppliers of tanks and associated hardware have moved rapidly to the new state of the art called for to meet the new standards for storage techniques, and to provide effective leak prevention and detection. This paper presents a chronology of the progress made to date in storage equipment and operating practices to provide the environmental protection demanded of underground tank owners and operators. Tank design, secondary containment, monitoring, spill and overfill protection, tank testing methods, and installation and closure procedures—as related to leak prevention—are presented     

A gis-based assessment on the vulnerability and future extent of the tropical forests of the congo basin

This paper examines the vulnerability of the Congo Basin's forests through a GIS platform, taking into consideration the variables of population growth, road density, logging concession, and forest fragmentation. The assessment indicates that the forests will continue to shrink towards the interior over the next 50 years. Current contiguous forests will fragment into three large blocks, including one on the west side of the Congo River and two in the Democratic Republic of Congo, while a large number of small forest patches will retain in the periphery of the large blocks. The study shows that integrated GIS assessment of the driving forces of tropical deforestation can shed light on the future forest distribution and provide a tool to address the broader implications of social and economic development for tropical deforestation.     

Climate change and agricultural technology adoption: the case of drought tolerant maize in rural Nigeria

Climate change is a major problem undermining agricultural production in Africa. Consequently, efforts are being made to provide farmers with adaptation technologies, but little empirical research exists on the determinants of adopting such technologies. This article addresses this research gap, using the case of drought tolerant maize (DTM) technology in Nigeria. With survey data from 200 farm households and econometric techniques, we explore the determinants of whether to invest and how much to invest in adaptation technology by smallholder farmers. Results from the study indicate that among the key determinants of adoption are access to the technology, complementary inputs, extension services, and climate change information. We also show that off-farm income and wealth status of a household play a significant role in adoption, implying capital constraints; hence, it can be difficult for resource-poor farmers to adopt the technology. Moreover, the farmers identified cost of the technology and complementary inputs, particularly fertilizer as major constraints to adoption. We conclude that while the DTM technology is suitable and important in helping smallholder maize farmers to continue to produce under a changing climate, more support is needed for them to invest in the technology and overcome adoption constraints. Necessary interventions include improving access to information about climate change and the available adaptation technology, timely access to the technology and complementary inputs, and improving access to credit, particularly for the resource-poor farm households.     

Monitoring agricultural burning in the Mississippi River Valley region from the moderate resolution imaging spectroradiometer (MODIS)

The 2003 active fire observations from the Moderate Resolution Imaging Spectroradiometer (MODIS), on board NASA's Terra and Aqua satellites, were analyzed to assess burning activity in the cropland areas of the Mississippi River Valley region. Agricultural burning was found to be an important contributor to fire activity in this region, accounting for approximately one-third of all burning. Agricultural fire activity showed two seasonal peaks: the first, smaller peak, occurring in June during the spring harvesting of wheat; and the second, bigger peak, in October during the fall harvesting of rice and soy. The seasonal signal in agricultural burning was predominantly evident in the early afternoon MODIS Aqua fire detections. A strong diurnal agricultural fire signal was prevalent during the fall harvesting months, as suggested by the substantially higher number (approximately 3.5 times) of fires detected by MODIS Aqua in the early afternoon, compared with those detected by MODIS Terra in the morning. No diurnal variations in agricultural fire activity were apparent during the springtime wheat-harvesting season. The seasonal and diurnal patterns in agricultural fire activity detected by MODIS are supported by known crop management practices in this region. MODIS data provide an important means to characterize and monitor agricultural fire dynamics and management practices.     

Contemporary forest loss in Myanmar: Effect of democratic transition and subsequent timber bans on landscape structure and composition

This study addresses the effect of political transition and subsequent timber bans on forest loss in Myanmar, in the context of identified drivers. Cook’s Distance (CD) was applied to remotely sensed time-series forest loss dataset to measure the effect of the events. Forest loss derived fragmentation metrics were linked to drivers at a landscape scale. Results show that at the national level, the political transition in 2011 had maximum effect (CD 0.935) on forest loss while the timber bans decreased forest loss by 612.04 km² and 213.15 km² in 2015 and 2017 (CD 0.146 and 0.035), respectively. The effect of the events varied for different States/Regions. The dominant drivers of change shifted from plantations in 2011 to infrastructure development in 2015. This study demonstrates the effects of policy on forest loss at various scales and can inform decision-makers for forest conservation, planning and development of mitigation measures.     

Impact of prolonged rainy seasons on food crop production in Cameroon

This study set out to examine why agricultural production in differing agro-ecological zones of the same country responds differently to a common environmental event (an extension of the rainy season). We find that the heavy reliance of farmers in the drier agro-ecological zones on seasonal cycles make them more vulnerable to an extension of the rainy season than those in regions where rainfall is less relied on. Effects in these vulnerable regions include significant damage to crops as well as a shortage in local markets, which raises prices of basic food commodities. The difference between prices in low and high food producing periods is low for crops that can easily be preserved during rains (such as cassava at 58% from an average of 20% in previous years and yams at 82% from 65%). Crops that depend on sunshine for preservation experience greater differences between low and high periods (maize at 92% from an average of 31% in previous years, sorghum at 180% from 53%, and beans at 68% from 42%). In zones with a history of unreliable dry seasons, farmers are more adapted to coping with an extension of the rainy season and possess technology and skills which can be made available to others in vulnerable zones through inter-regional knowledge transfer of knowledge and skills. This study further reinforces the understanding that isolated climate shocks could be important in understanding and managing vulnerability. Also, vulnerability is quite variable even among communities in the same country, in which people practice the same economic activity and are exposed to the same shock.     

Food security and climate change in drought-sensitive savanna zones of Ghana

Desertification, climate variability and food security are closely linked through drought, land cover changes, and climate and biological feedbacks. In Ghana, only few studies have documented these linkages. To establish this link the study provides historical and predicted climatic changes for two drought sensitive agro-ecological zones in Ghana and further determines how these changes have influenced crop production within the two zones. This objective was attained via Markov chain and Fuzzy modelling. Results from the Markov chain model point to the fact that the Guinea savanna agro-ecological zone has experienced delayed rains from 1960 to 2008 while the Sudan savanna agro-ecological zone had slightly earlier rains for the same period. Results of Fuzzy Modelling indicate that very suitable and moderately suitable croplands for millet and sorghum production are evenly distributed within the two agro-ecological zones. For Ghana to adapt to climate change and thereby achieve food security, it is important to pursue strategies such as expansion of irrigated agricultural areas, improvement of crop water productivity in rain-fed agriculture, crop improvement and specialisation, and improvement in indigenous technology. It is also important to encourage farmers in the Sudan and Guinea Savanna zones to focus on the production of cereals and legumes (e.g. sorghum, millet and soybeans) as the edaphic and climatic factors favour these crops and will give the farmers a competitive advantage. It may be necessary to consider the development of the study area as the main production and supply source of selected cereals and legumes for the entire country in order to free lands in other regions for the production of crops highly suitable for those regions on the basis of their edaphic and climatic conditions.