Thursday 4 March, 07:00 am – 01:00 pm, Kunyang (pick-up at your hotel)
The Kunyang mining site is a Phosphate mine, 60 km south of Kunming City. Kunyang is one of four mining sites managed by Yunnan Phosphate Chemical Group Co., Ltd. (YPC) and one of the largest phosphate mines in China, with revegetation of mined landscapes dating back to 1983. However, the phosphate resources at the mining site are drying up, leaving only environmental issues.
Facilitators: Lingling Shi (KIB), Anne Ostermann (ICRAF), Samantha Karunarathna (MFU)
Ongoing activities include:
- Vegetation screening and utilizing plant species for ecological restoration
- Evaluation and improvement measures of soil related to land reclamation
- Key technologies including nursery operation and model integration for ecological recovery
First Stop: Sci-tech & Industry trade branch
The Sci-tech & Industry trade branch is a supporting department of the mining company responsible for scientific research and testing, and business establishment. The nursery is an important part of this department, supporting restoration by the introduction of new species, cultivation of seedlings, and the development of new planting methods. In collaboration with ICRAF, the company selected several economic plant species, including trees, grasses, and flowers to test their potential in restoration. Apart from species selection, ICRAF supports the mining company with fertilization and cultivation recommendations.
Second stop: Undermining activities zones
The Kunyang mining site covers an area of 100 km2, and has supplied 25% of China’s phosphate fertilizer in the last 20 years. Before exploitation and extraction of the parent rock material, the soil layer is removed and stored separately. In the landscape restoration process, this soil is then used to terrace the degraded land before beginning the reforestation process with forests and agroforestry systems.
Third stop: The restoration projects
During the restoration process, terraces are covered with a layer of approximately 60 cm of soil material. The re-cultivation strategy on these sites has changed within the last 30 years. Sites are now being re-cultivated with multiple tree species or agroforestry systems, whereas in the beginning of restoration 30 years ago, large stretches of land were planted with only a single tree species.
Restoration is an integral part of the mining company’s activity. The process of restoration begins shortly after the mining process is completed. However, despite rapid tree growth, it can take up to several years to restore soil fertility. Agroforestry systems may speed up this process and with this in mind, ICRAF is investigating the effects of different agroforestry systems versus forested land regarding the restoration of soil functions. The ICRAF team has established agroforestry trials in which trees are intercropped with different cash crops such as flowers and mushrooms, and is studying the impact of soil conditions under different restoration approaches.