"Adaptation Strategies to Climate Change and Sustainable Land Use"
Junior Research Group Adaptation Strategies to Climate Change and Sustainable Land Use in Central Asia (Turkmenistan and Xinjiang, China) Institute for Botany and Landscape Ecology, Greifswald University funded by: Bauer-Hollmann Foundation und Rudolf und Helene Glaser Foundation In the German Science Centre More than 50% of Central Asia is covered by deserts (Figure 1). The remaining areas are steppes and mountain ranges. The agriculture, settlements, as well as biodiversity concentrate along the rivers, like the Amu Darya and Syr Darya, which drained in the Aral Seaen Aral-See, and the Tarim River in Xinjiang, China. Figure 1: Map of Central Asia with the location of the study sites: A: Amu Darya Nature Reserve, B: Xayar Tarim Shangyou Nature Reserve, C: Tarim Huyanglin Nature Reserve. Names of the water reservoirs are: 1: Tujamujun, 2: Shardara, 3: Kajrakum, 4: Toktogul, 5: Shangyou and Shengli, 6: Daxihaizi. All kind of land use as well as the natural ecosystems in the desert areas of Central Asia receive their water directly or indirectly from the rivers. The natural ecosystems, i.e. riparian forests, reed beds, and shrub lands, take up water from the groundwater, which is refiled from the rivers. The agricultural fields are irrigated with river water. Cotton is the main crop. The irrigation has lead to large scale soil salinization in the region, because plants like cotton only are able to take up water near the soil surface. Under undisturbed natural vegetation soil salinization is rare, because the water uptake into the plant takes place deep in the groundwater layer and not near to the soil surface. The rivers of Central Asia are fed by melting water and rainfall in the mountain ranges of the region, i.e. the Pamir, Hindukush, and Tianshan. Thus, the river carry floods during summer, while they carry little water during spring. The natural vegetation is adapted well to this water distribution, because it uses the groundwater. The groundwater is refilled during each flood and stored until spring time of the following year when the vegetation needs the water. In contrast, cotton has the highest water demand during spring and early summer, i.e. the time with the lowesat river runoff. Photographs on the cover: Top left: The riverbed of the Tarim, China, July 2008. The river runoff was interrupted due to the warm winter 2007/2008. Top right: Cotton harvest, Tarim floodplain, Sept. 2008. This cotton field was irrigated with fossil groundwater. Bottom left: Stand of Lop Kendir (Apocynum venetum), Sept. 2008. The leafs are harvested regularly in October and sold as tea. Bottom right: Riparian forest from Populus euphratica in the core zone of the Tarim Huyanglin Nature Reserve, China. Due to climate change, parts of the glaciers in the mountains melt and disappear. Furthermore, the winter snowfall decreases. Therefore, river runoffs will decrease in the future, resulting in an increasing competition for water between the man-made and natural ecosystems. Against the background of climate change and shrinking river runoff in Central Asia, we have to raise the question of the benefits delivered by the ecosystems in turn for their water consumption (Figure. 2). The term benefits includes economic benefits as well as ecosystem services. The most important ecosystem services are Carbon sequestration and combating desertification. Figure 2: Scheme of the river water supply and water diversion into the three main land covers competing for water along the rivers of Central Asia, i.e. riparian forests, grasslands, and irrigation agriculture with their economic and ecological benefits (green and yellow text fields, respectively). Against the background of climate change and shrinking river runoff in Central Asia, this Junior Research Group has the following objectives: • Investigation of the water consumption and benefits of the relevant man-made and natural ecosystems in Central Asia • Investigation of native plant species with regard to their potentials for sustainable utilization. Among the native plant species, reed (Phragmites australis) and Lop Kendir (Apocynum venetum) have a high potential for utilization. These two plant species should become part of an adaptation strategy with regard to climate change. Reed is used a raw material in the paper industry and for house construction. Lop Kendir is used as medicinal plant and currently its application as fibre plant is tested. The study areas fort his project are the middle reaches of the Amu Darya in Turkmenistan as well as the Tarim River in Xinjiang, China. Project partners are the National Institute of Desert, Flora, and Fauna, Turkmenistan, and the Xinjiang University, China. The project results will be shared with the local decision makers in order to be applied for water allocation and land use planning. The Junior Research Group Adaptation Strategies to Climate Change and Sustainable Land Use in Central Asia (Turkmenistan and Xinjiang, China) started in January 2009 and terminates by end of 2011. The whole budget amounts to EUR 338.520,- and is funded b< the Bauer-Hollmann Foundation and the Rudolf und Helene Glaser Foundation in the German Science Centre.