Analysis of the Impacts of armed conflict on the Eastern Afromontane forest region on the South Sudan — Uganda border using multitemporal Landsat imagery

Abstract

The impacts of armed conflict on ecosystems are complex and difficult to assess due to restricted access to affected areas during wartime making satellite remote sensing a useful tool for studying direct and indirect effects of conflict on the landscape. The Imatong Central Forest Reserve (ICFR) in South Sudan together with the nearby Dongotana Hills and the Agoro-Agu Forest Reserve (AFR) in Northern Uganda share a boundary and encompass a biologically diverse montane ecosystem. This study used satellite data combined with general human population trends to examine the impact of armed conflict and its outcome on similar forest ecosystems both during and after hostilities have occurred. A Disturbance Index (DI) was used to investigate the location and extent of forest cover loss and gain in three areas for two key time periods from mid-1980s to 2001 and 2003 to 2010. Results indicate that the rate of forest recovery was significantly higher than the rate of disturbance both during and after wartime in and around the ICFR and the net rate of forest cover change remained largely unchanged for the two time periods. In contrast, the nearby Dongotana Hills experienced relatively high rates of disturbance during both periods; however, post war period losses were largely offset by some gains in forest cover. For the AFR in Uganda, the rate of forest recovery was much higher during the second period, coinciding with the time people began leaving overcrowded camps. The diversity and merging of floristic regions in a very narrow band around the Imatong Mountains makes this area biologically distinct and of outstanding conservation importance; therefore, any future loss in forest cover is important to monitor — particularly in South Sudan where large numbers of people continue to return following the 2005 peace agreement and the 2011 Referendum on Independence.

Introduction

The direct effects of war on civilians are generally well-understood and have been extensively documented (Clodfelter, 2002, Ismael, 2007, Keegan, 1994, Sidel and Levy, 2008, Tardanico, 2008). The indirect effects of war due to the use of munitions on a nation's land, air and water can also have adverse, long-term and far-reaching effects on human populations and the surrounding environment (Joksimovich, 2000). Often overlooked is the effect of war on land cover, which in turn impacts biodiversity (Dudley & Woodford, 2002), despite the fact that 90% of the major armed conflicts between 1950 and 2000 occurred within countries containing biodiversity hotspots and more than 80% took place directly within the hotspots (Hanson et al., 2009). Several studies have concluded that armed conflict is generally deleterious to plants and animals due to habitat destruction and fragmentation, direct loss of animals from poaching or land mines, over-exploitation and degradation of natural resources, and increases in land and water pollution (Baral and Heinen, 2005, Eniang et al., 2007, Gleditsch, 1998, Jacobs and Schloeder, 2001, Kalpers, 2001, Kanyamibwa, 1998, Messina and Delamater, 2006, Nils Petter Gleditsch, 1998, Pearce, 1995, Shambaugh et al., 2001, Van Houven and Nimir, 2004, Vanasselt, 2003). In some cases, however, wars have been found to have a positive impact on biodiversity, through the formation of “no go zones” due to reduced security, resulting in a decrease in human pressure on the environment and wildlife (Kaimowitz and Faune, 2003, Martin and Szuter, 1999, McNeely, 2003, Nietschmann, 1990, Vogel, 2000).

Difficulty of access to an area during war combined with no clear spatial or temporal definition for the extent of conflict makes an accurate and timely assessment of the impacts extremely challenging (Glew & Hudson, 2007). Because of these limitations, information derived from satellite remote sensing data can provide insight into how conflict directly affects the physical landscape during wartime, and indirectly leads to changes in human populations and land use activity that drive the observed land cover modifications. For example, data from satellite remote sensing have been used to identify the effects and quantify environmental damages in Kuwait from military activity that occurred during the 1990–1991 Gulf War (El-Gamily, 2007, Koch and El-Baz, 1998). Satellite imagery was also used to show how the spraying of defoliants on coca crops in Columbia negatively affected native plant and food crop parcels (Messina & Delamater, 2006) and to monitor the burning of fields, forests and villages by the Turkish army in Kurdistan (De Vos et al., 2008).

Because the impacts of war on the environment are often felt both prior to and following conflict (Machlis & Hanson, 2008), time-series of satellite imagery can be used to monitor the landscape over a longer period to record changes resulting from the effects of war (Pearce, 1995), including the abandonment of agricultural lands (Suthakar and Bui, 2008, Witmer, 2008). One of the more visible effects of war is the imprint left on the landscape due to mass migration and subsequent settlement of people in internally displaced person (IDP) or refugee camps. Much has been written and debated about the impact of IDPs and refugees on the environment, but it is generally agreed that emigration tends to reduce pressure at the origin and increase pressure at the destination (Hugo, 1996), leading to desertification, deforestation, and general land degradation at the latter (Allan, 1987, Biswas and Tortajada-Quiroz, 1996, Ghimire, 1994, Hugo, 1996, Sato et al., 2000). This has significant implications for the environment since the number of forcibly displaced people has risen in recent years, despite a reduction in the actual number of civil conflicts (Cohen & Deng, 2008). Peace can be equally damaging to the environment if mass migration is reversed back to the point of origin, accompanied by resource exploitation necessary to rebuild communities and revive the local economy (Robinson & Sutherland, 2002).

The objective of this study was to use information derived from remotely sensed satellite imagery to compare and contrast changes in forest cover in a cross-border conservation hotspot located on the border of South Sudan and Northern Uganda. We hypothesize that forest cover will remain constant or increase during the war periods on the South Sudan side of the study area as people leave the region and abandon farming and other activities that affect land cover, and that forest cover will decline with migration of people back to the area. In contrast, forest cover is expected to decrease during the war years in the Northern Uganda study area as a result of the heavy concentration of IDP camps located in the study area and then rebound in recent years due to abandonment of the camps.