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Physics-based remote sensing in littoral environments for ecological monitoring and assessment is a challenging task that depends on adequate atmospheric conditions during data acquisition, sensor capabilities and correction of signal disturbances associated with water surface and water column. Airborne hyper-spectral scanners offer higher potential than satellite sensors for wetland monitoring and assessment. However, application in remote areas is often limited by national restrictions, time and high costs compared to satellite data. In this study, we tested the potential of the commercial, high-resolution multi-spectral satellite QuickBird for monitoring littoral zones of Lake Sevan (Armenia). We present a classification procedure that uses a physics-based image processing system (MIP) and GIS tools for calculating spatial metrics. We focused on classification of littoral sediment coverage over three consecutive years (2006)(2007)(2008) to document changes in vegetation structure associated with a rise in water levels. We describe a spectral unmixing algorithm for basic classification and a supervised algorithm for mapping vegetation types. Atmospheric aerosol retrieval, lake-specific parameterisation and validation of classifications were supported by underwater spectral measurements in the respective seasons. Results revealed accurate classification of submersed aquatic vegetation and sediment structures in the littoral zone, documenting spatial vegetation dynamics induced by water level fluctuations and interannual variations in phytoplankton blooms. The data prove the cost-effective applicability of satellite remote-sensing approaches for high-resolution mapping in space and time of lake littoral zones playing a Guest editor: Martin A. Stapanian / QuickBird satellite imagery as a tool for restoration and rehabilitation of Lake Sevan, Armenia

Armed conflicts are globally widespread and can strongly influence societies and the environment. However, where and how armed conflicts affect agricultural land-use is not well-understood. The Caucasus is a multi-ethnic region that experienced several conflicts shortly after the collapse of the Soviet Union, most notably the two Chechen Wars, raising the question how agricultural lands were changed. Here, we investigated how the distance to conflicts and conflict intensity, measured as the number of conflicts and the number of casualties, affected agricultural land abandonment and subsequent re-cultivation, by combining social, environmental and economic variables with remotely-sensed maps of agricultural change. We applied logistic and panel regression analyses for both the First Chechen War (1994-1996) and the Second Chechen War (1999-2009) and interacted conflict distance with conflict intensity measures. We found that agricultural lands closer to conflicts were more likely to be abandoned and less likely to be re-cultivated, with stronger effects for the First Chechen War. Conflict intensity was positively correlated with agricultural land abandonment, but the effects differed based on distance to conflicts and the intensity measure. We found little re-cultivation after the wars, despite abundant subsidies, indicating the potentially long-lasting effects of armed conflicts on land-use. Overall, we found a clear relationship between the Chechen Wars and agricultural land abandonment and re-cultivation, illustrating the strong effects of armed conflicts on agriculture.

The extent and condition of forest ecosystems in Armenia have decreased drastically since the disintegration of the Union of Soviet Socialist Republics (USSR). This decline is not only a consequence of the recent history of the area, but also the result of decades of forest policies, management and forest-use practices. To reverse the negative trends, it is important for stakeholders, scientists, resource managers and policy makers (in Armenia and abroad) to understand the influential factors in the decline, yet such information is scarce, highly fragmented, written in Armenian or Russian, and inaccessible to the international community. This paper aims to contribute to the knowledge base of the international community by presenting and contrasting the most important issues and processes that have affected forest cover in Armenia during the USSR (1920–1991) and independence periods (1991–to date). For each period, the legal framework, the forest inventory practices, forest use, management and conservation practices, the forestry education, and the perception of the forests by forest communities and society at large are presented and discussed. Except for the social perception of the forests, the most relevant aspects of these issues have scarcely changed from one period to the next. There is a need to address the most pressing problems and improve the current conditions of the forests and the forestry sector in Armenia.

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