Cities at the fringe of the Taklimakan desert in NW China are prone to dust and sand storms with serious consequences for human well-being. The Kأ¶kyar Protection Forest was established in the 1980s as an ecological engineering project with the intent of protecting the city of Aksu, NW China, from these impacts. It is designed as a combination of poplar shelterbelts and orchards, irrigated by river water from the Aksu River, the main tributary of the Tarim River. Prevalent literature describes it as an afforestation project for combatting desertification with manifold positive effects for the economic, social, and environmental dimension of sustainable development. This paper sets out to challenge these claims by a sustainability assessment in which the plantation is examined from a broader perspective, embedding it to the wider context of social and environmental problems in South Xinjiang. Methods comprise evapotranspiration calculations, interviews, a socioeconomic household survey, stakeholder dialogues, and literature research. Results affirm its economic sustainability, but see a mixed record for the social sphere. From the nature conservation point of view, it has to be classified as unsustainable because its high irrigation water consumption results in the downstream desiccation and desertification of natural riparian forests along the Tarim River, causing a forest loss in the downstream area twice the size of the forest gain in the upstream area. There is a trade-off between artificial shelterbelt plantations for urban ecosystem services on the one hand side, and natural riparian forests and their biodiversity on the other hand side. The paper recommends restricting agricultural extension, and using locally adapted less water consuming agroforestry schemes to protect urban dwellers from dust stress.
As a response to the dust problems, in the 1980s the local authorities decided to lay out a peri-urban shelterbelt plantation, called Kökyar Protection Forest. Work began in 1986 and was completed in 1990, the plantation then covering an area of 1308 ha . From 1990 onward, the project was extended by three more project periods, each of which converted more patches of desert land into forest plantations (cf. Figure 3). The four project periods and their corresponding areas were then chronologically labelled Kökyar I to IV, while the complete title, Kökyar Protection Forest, usually refers to all four project areas together. The Kökyar Protection Forest is designed as a raster of shelterbelt strips in which rectangular orchard plots are embedded. The shelterbelt strips consist mainly of white poplar (Populus alba var. ‘Pyramidalis’), while the orchard plots are mainly planted with apple and pear. Jujube, walnut, and grapes and others play a minor role (Kökyar socio-economic household survey). The share of the shelterbelt strips in the plantation has dropped from 52% in Kökyar I to 42% in Kökyar II and to only 10% in Kökyar III, in favour of increasing orchard shares (comp. Table 1). the Kökyar Protection Forest is an artificial forest plantation that depends fully on regular irrigation fed by river water. Since its irrigation water is diverted from the Tarim River’s main tributary Aksu River, every drop of water spent on the upstream Kökyar Protection Forest is directly missing in the downstream areas. By this, it contributes to the ongoing degradation and desiccation of the natural Tugai forests in the middle and lower reaches of the Tarim River, consequently reducing ecosystem services there. This makes clear that the ecosystem services at Aksu are not created out of thin air, but rather translocated from downstream
|Climate change impacts||Effect of Nbs on CCI||Effect measures|
|Other climate impact||Unclear results||sand/dust storm reduction - analysis taken from lit and a secondary data set "An improvement is perceived and described by local inhabitants [40,43]. Additionally, a data set from 1996 shows a decrease of annual windborne sand events from 11.4 before the establishment of Kökyar down to 4.3 since its establishment . However, the data does neither reveal the intensity and duration of each event nor the precise contribution of the Kökyar plantation to this reduction . The precise metrics of the protective effect therefore stay unknown. "|
|Reduced water availability||Negative||Water availability - "The water use calculation is the core argument of the paper. By comparing the water consumption of the Kökyar Protection Forest at Aksu with the water consumption of the natural Tugai forests at the middle and lower reaches of the Tarim River, it reveals the area of Tugai forests that are sacrificed for the Kökyar plantation. It was executed as an evapotranspiration calculation using the Penman-Monteith equation [44,45], which can provide a good estimation of long-term evapotranspiration but should not be understood as an exact assessment of actual evapotranspiration."|
around the city of Aksu is a river oasis on the northern edge of the Taklimakan Desert, Xinjiang Uyghur Autonomous Region, Northwest China