Review of the investigation and integrated renovation on rocky desertification in Yunnan Province, China

As one of the provinces with largest karst area,the size of karst area is 110,875.7 km2 in Yunnan province,with a rocky desertification size of 34,772.76 km2 of in the karst area.The rocky desertification has seriously restricted the sustainable development the local economy.The ecologic and geologic environment is very fragile,and the land is very droughty and lacks of soil in rocky desertification areas.The main factors that directly impact on the rocky desertification include excess population relative to the environment bearing capacity,unreasonable exploitation of land,impacts of mining activities on local ecology and environments,and industrial pollution,etc.In addition,low-level utilization of green resources have an indirect influence on the development of rock desertification.These include natural resources as biology,tourism,geothermal water and mineral water,which are much abundant in the karst area.After full investigations and comprehensive studies,an integrated renovation program has been completed.Based on this program,biological,engineering,economic and social measures have been implemented for the integrated renovation of the rockydesertification.It should be stressed that the Department of Land and Resources (DLR) has implemented many effective measures,such as demonstration projects for the development of karst groundwater and the integrated renovation of rocky desertification,land consolidation,mining geo-environmental protection and associated mine rehabilitation,and geopark ecological construction and environmental protection,etc.These measures have directly reduced land area of rocky desertification land and effectively restricted those artificial or natural factors leading to rocky desertification in the karst area.In the meantime,the department has increased job opportunities and promoted rural urbanization in small towns through effective development of valuable geological resources,which in turn the efforts of the DLR have been paid off.The main problems in the integrated renovation include the following parts.Firstly,the renovation areas of the rocky desertification are sporadically distributed and the change of the regional landscape is small.Secondly,the correlation and overall response of karst basin have been less well recognized and the selected renovation methods are improper.Thirdly,the investigation and monitor are not updated in time so that the effects and progress of the renovation are inaccurate.Fourthly,the development and utilization of groundwater resource as well as the protection of the resource and environment have not been implemented well.Finally,the coordination and cooperation among different governmental departments for the integrated renovation projects are not enough.These problems have negative influence on the efficiency of the integrated renovation of the rocky desertification.In this paper,the distribution diagram of rocky desertification,the investigation intensity map and the distribution diagram of the demonstration engineering are valuable material to have a better understanding of the rocky desertification,environmental conditions and resources,and the investigation progress in Yunnan Province.