«ASSESSMENT OF SOCIOLOGICAL AND ECOLOGICAL IMPACTS OF SAND AND GRAVEL MINING – A CASE STUDY OF EAST GONJA DISTRICT (GHANA) AND GUNNARSHOLT (ICELAND) ...»
Land Restoration Training Programme Final project 2009
Keldnaholt, 112 Reykjavík, Iceland
ASSESSMENT OF SOCIOLOGICAL AND ECOLOGICAL
IMPACTS OF SAND AND GRAVEL MINING – A CASE
STUDY OF EAST GONJA DISTRICT (GHANA) AND
Jafaru Adam Musah
Environmental Protection Agency Post Office Box 620 Tamale, Northern Region, Ghana email@example.com Supervisor Mr. Björn H. Barkarson Environmental and Infrastructural Consultant VSO Consulting, Reykjavik, Iceland firstname.lastname@example.org
Specific objectives were: i) to assess agricultural losses through sand and gravel mining in the areas; ii) to gather communities’ and stakeholders’ perceptions of the socio-ecological impacts of gravel and sand mining; iii) to assess and compare regulations and policies govern- ing such land use; iv) to suggest interventions that can assist in mitigating negative impacts that might be identified during the study. The study revealed fewer mines around Gunnarsholt than in EGD and that mining activities mostly occur in barren lands whilst in EGD the mining activities occur in productive agricultural lands. Also, the impact of gravel mining on agri- culture is greater in EGD compared to the Gunnarsholt area. Policies and regulations on min- ing vis-à-vis monitoring and enforcement activities are quite explicit in the Gunnarsholt area compared to EGD. Other environmental impacts of the two study areas were similar and clear sociological impact appeared in the generation of conflicts and other confrontations.
75 LRT 2009
1. INTRODUCTION Mining of natural aggregates, including both sand and gravel and crushed rock, represents the main source of construction aggregates used throughout the world, with examples from Australia (Erskine & Green, 2000), France (Petit, Poinsart & Bravard, 1996), Italy (Surian & Rinaldi, 2003), the USA (Kondolf, 1994), Belgium (Gob, Houbrechts, Hiver & Petir, 2005) and Britain (Sear & Archer, 1998). However, operations of mining, whether small- or largescale, are inherently disruptive to the environment (Makweba & Ndonde, 1996). Also mining of aggregate frequently generates land use conflicts in populated areas due to its negative externalities including noise, dust, truck traffic, pollution and visually unpleasant landscapes (Willis & Garrod, 1999). It also can represent a conflict with competing land uses such as farming, especially in areas where high-value farmland is scarce and where post-mining restoration may not be feasible. As pointed out by social and environmental activists there are potential linkages between mineral resources and conflict and consequential underdevelopment (Ross, 2001).
Gravel extraction can cause changes to channel morphology in rivers through the lowering of the riverbed during extraction (Rinaldi, Wyzga & Surian, 2005). This is enhanced by the disruption to bed armour caused by excavations and the movement of machinery which makes the bed vulnerable to fluvial erosion (Mossa & McLean, 1997).
In the Northern Region of Ghana and the East Gonja District (EGD) in particular, commercial gravel extraction to supply aggregate to the construction industry has been on the increase in recent years. This has to a large extent contributed to land degradation and desertification through the destruction of economically important trees, mostly indigenous in nature. This practice leaves behind bare soil and a large expanse of gullies which can collect water during rainy seasons. This can result not only in health-related problems for neighbourhood communities, but can cause negative impacts on the environment as well (Heath, Merefield & Paithankar, 1993; Veiga & Beinhoff, 1997; Warhurst, 1994, 1999).
In southern Iceland with particular attention to Gunnarsholt, which 50 years ago was almost a desert area, a significant number of mining sites are dotted across its length and breadth (Sigurjonsson, 1958; Gylfi Juliusson, Pers.com.). These mines mainly are used to supply aggregate to the construction industry.
Nonetheless, gravel sites from the study areas are a particularly attractive source of aggregate as they are relatively well sorted, easily accessible and cheap to extract (Sear & Archer, 1998).
This has potentially adverse impacts on the natural environment, society and cultural heritage, the health and safety of mine workers, and communities based in close proximity to operations (Moody & Panos, 1997) and dislocation (Akabzaa, 2000). However, although people in general are familiar with the need and importance of sand and gravel mining for construction
material, the awareness of the negative impact this has on vegetation, biodiversity and food security may not be as commonly known.
Despite widespread occurrence and potential impact on the environment and agricultural lands, sand and gravel mining has received little attention. Even though some studies have improved our consciousness of the impacts, attention usually seems to be focused on mining along river banks and is seldom considered in the context of farms/cultivated lands.
This study sought to assess the sociological and ecological impacts of sand and gravel mining with particular attention to the East Gonja District of Ghana vis-à-vis the Gunnarsholt area of Iceland.
The main objective of this study was to carry out an assessment of the sociological and ecological impact of sand and gravel mining in the East Gonja District of Ghana and the Gunnarsholt area of Iceland. The more specific objectives of the project were:
• To estimate agricultural losses due to sand and gravel mining in the study areas.
• To gather communities’ and stakeholders’ perceptions of the socio- and ecological impacts of sand and gravel mining in the areas.
• To assess and compare regulations and policies governing such land use in the areas.
• To suggest interventions that could assist in mitigating negative impacts that might be identified during the study.
2. STUDY AREAS The study was carried out in two study areas, East Gonja District (Ghana) and the Gunnarsholt area (Iceland).
2.1 East Gonja District 2.1.1 Location and size East Gonja District is located in the south-eastern section of the Northern Region of Ghana.
The district lies between Lat. 8°N & 9.29°N and Long. 0.29°E & 1.26°W (East Gonja District Assembly, 2006). It shares boundaries with the Yendi and Tamale districts to the north, the Central Gonja District to the west, the Nanumba-North and Nanumba-South Districts to the east, and the Volta and Brong Ahafo Regions to the south (see Fig. 1).
The total land area of the district is 10,787 km2, occupying about 15% of the landmass of the Northern Region (East Gonja District Assembly, 2006). The district comes first in terms of land area (size) among the districts of the Northern Region.
Fig. 1. Map of Ghana showing the location of East Gonja District. (Source: modified from Google earth).
The topography of the district is typical of the Northern Region, generally flat with few undulating surfaces. Nowhere does the land rise as high as 200 metres. The district is underlain by the Voltarian sedimentary formation with low potential for mineral formations and poor water retention (East Gonja District Assembly, 2006).
The average annual precipitation in the area is 1,050 mm which is considered enough for a single farming season. Temperatures are usually high, averaging 30°C (East Gonja District Assembly, 2006).
The main drainage system in the district is made up of the Volta and some of its major tributaries, including the White Volta, the Dakar and Oti Rivers. There is a good flow of water collected and stored in Lake Volta, which potentially exists for irrigation and small dam sites.
The natural vegetation in the district is Guinea Savannah Woodland, which consists of trees that are drought resistant (East Gonja District Assembly, 2006).
Most of these trees are of economic value. Notable amongst them are the shea and dawadawa trees (East Gonja District Assembly, 2006). Compared to the rest of the Northern Region, the tree cover is dense although intense harvesting for fuel wood is reducing the natural flora.
At the extreme south-east, the vegetation is dense and semi-deciduous trees such as oil palm
trees, raffia palms and others can be found. There are three major groups of soils in the district:
Alluvial Soils, Ground water Laterites and Savannah Ochrosols (East Gonja District Assembly, 2006).
2.1.2 Climate and vegetation The East Gonja District lies in the Tropical Continental climatic zone with the mid-day sun always overhead. As a result, temperatures are fairly high, ranging between 29°C and 40°C.
The maximum temperature is usually recorded in April, towards the end of the dry season.
Minimum temperatures are recorded around December-January, during the Harmattan (dry wind) period (East Gonja District Assembly, 2006).
Just like any other part of West Africa, the district comes under the influence of the wet SouthWest Monsoon and the dry North-East Trade winds which are associated with the rainy season and the dry harmattan conditions, respectively (East Gonja District Assembly, 2006).
The rainfall pattern in East Gonja is characterized by irregularity and variability in terms of timing of onset, duration and total amount of rainfall, which has been the key limiting factor affecting crop production in the district (East Gonja District Assembly, 2006).
2.1.3 Demographic characteristics According to the Ghana Population and Housing Census (2000), the population of the East Gonja District was 174,500 as in 2000. Currently it is estimated at around 198,000, using an annual rate of growth 2.1% per annum (East Gonja District Assembly, 2006). The district’s share of the total population of the Northern Region is 9.7%. The total population of the Northern Region stood at 1,820,806 (as of 2000). The district’s population growth rate is 2.1% (1984–2000), lower than both the regional and national averages of 2.9% and 2.5%, respectively (East Gonja District Assembly, 2006).
This relatively low population growth rate could be explained by increased migration from the District combined with the modest success in population control and education measures of the Ministry of Health. This lower population growth rate in East Gonja District is an asset to be maintained and reinforced through conscious policy and promotional and educational measures.
2.1.4 Spatial Distribution of Population The population of the district is predominantly rural. A total of 152,146 of the population, representing 86.4% (in 2000), are located in rural communities (East Gonja District Assembly, 2006). This indicates a decline in the rural population compared to the 1984, 1970 and 1960 figures of 86.8%, 91.2 and 100%, respectively. The proportion of the population located in
urban communities is gradually increasing. The urban population in the district in 1970 was merely 8.8% and this had increased to 13.6% by 2000 (East Gonja District Assembly, 2006).
2.2 Gunnarsholt 2.2.1 Location and climatic condition According to world map co-ordinates, the location of Gunnarsholt in Iceland is at Lat. 63°51’00 N and Long. 20°11’60 W. The area’s mean annual temperature and rainfall do not vary much from the national figures. The mean annual temperature varies from 2–6°C, and annual total precipitation varies from 300–3500 mm (Barkarson & Johannsson, 2009).
2.2.2 Soil type and geology The Gunnarsholt area is in close proximity to one of Iceland’s most active volcanoes, Mt Hekla. It has erupted at least twice each century on average (Thorarinsson, 1970) and is the primary local source of the vast tephra (ash) deposits to the north of Gunnarsholt. As these deposits became increasingly unstable during the past several centuries, aeolian erosional activity in the area intensified. The latter part of the 19th and beginning of the 20th centuries were characterised by sand encroachment in the area, devastating many farms and leaving infertile sandy desert in place of arable land (Sigurjonsson, 1958). The land in the vicinity of Gunnarsholt was totally desertified and the aeolian activity caused rapid sedimentation of airborne materials at sites where vegetation remained. As a result, the soil at the Gunnarsholt study area consists of a thick mantle of reworked and in situ volcanic materials. Soil that forms in volcanic ejecta develops unique characteristics that are referred to as andic soil properties. These are therefore classified as a special soil type such as Andosols (FAO-UNESCO, 1988) or Andisols (USDA, 1994). The unique properties of Andisols include their low bulk density and high water retention ability, with water infiltration and hydraulic conductivity resembling very silty soils (Maeda et al., 1977; Wada, 1985).