The challenge and future of rocky desertification control in Karst areas in Southwest China

Introduction Conclusions References

. This tension 32 between people and land caused by overpopulation and land scarcity is severe ( Fig.3 and 33 Table 2). It has forced peasants to reclaim wasteland and cultivate on steep slopes, which has 1 become common in the karst areas in Southwest China (Fig.2). Yet, steep slopes are precisely 2 the places most at risk for rocky desertification (Jiang et al.,2009). It is thus fair to conclude 3 that backward economic development is the main cause of rocky desertification in the region 4 (Bai et al.,2013), that is to say the excessive human interference due to backward economic 5 development is the main cause of rocky desertification. 6 Similar to the situation in karst areas in China, in European Mediterranean region, agriculture 7 production and deforestation caused by unreasonable human activities (Kéfi et al.,2007), such 8 as slash-and-burn cultivation and destroying forest for land reclamation, were major causes of 9 rocky desertification. But the existing hillslopes are terraced by machine because the land 10 prices were increasing. Grapes and other economic crops were planted instead of food crop 11 with the extensive machinery management. For example, bulldozers torn off epikarst from 12 ground into gravel, and then compacted it with added topsoil(Ford and Williams,2007). 13 Meanwhile, a strategy for use of vegetation to combat rocky desertification and land 14 degradation has been developed in European Mediterranean region (Hooke and 15 Sandercock,2012). In short, rocky desertification in European Mediterranean region is 16 triggered by special geological environment and excessive human interference, both of which 17 directly or indirectly affected water budgets and land degradation through associated changes 18 in land use patterns. But in China, with increasing population and limited non-agricultural 19 employment, labor in this region continues to be invested in cultivating limited land in order 20 to increase land production, which has caused a decrease in household's marginal benefit and 21 agricultural involution. With the continuous development of agricultural involution, the 22 phenomena of over-exploitation, overgrazing, deforestation, and steep slope reclamation 23 become increasingly serious, resulting in the degradation of the ecological environment, and 24 finally triggering rocky desertification. In other words, the area has fallen into a vicious cycle 25 of poverty and environmental degradation at different scales (Fig.4). 26

The challenges rocky desertification control confronted 27
Rocky desertification control is carried out through the participation of the government, 28 peasants, enterprises, and scientific researchers. It is a continuous process of coordinating 29 various multistakeholders for a common goal. Existing rocky desertification control practices 30 are mainly driven by the government and the role of peasants is not significant. The 31 achievement of rocky desertification control was hindered because various multistakeholders, 32 such as the government, peasants, and enterprises, were overly concerned with their own 1 interests (Enterprises are mainly to make practical rocky desertification control plannings 2 according to the government's target, and to take measures to restore rocky desertification 3 land). Furthermore, policies which aimed to achieve a common goal, such as the standards of 4 planting density set by the government, were not effectively implemented because they lacked 5 effective mechanisms to coordinate multistakeholders interests. The construction of 6 governance models was dominated by the government administration, research institutions, 7 and enterprises. Although some good comprehensive benefits were achieved, some 8 governance models were made without considering the current national economic situation. 9 Economic development led to the outflow of the rural labor force and some governance 10 models were overly dependent on external input, which could not be a sustainable 11 development solution since it lacked supporting industries separate from national input. 12 . Moreover, in the process of formulating rocky desertification governance 13 models, peasants were mainly involved as builders and participants, but were excluded from 14 any independent development of rocky desertification control. Furthermore, some governance 15 models of rocky desertification control did not consider peasants' conditions and needs (Cai 16 and Zhang,2009), and therefore destroyed any incentive for peasant compliance, especially 17 for those located out of the control demonstration area that were devoid of capital, technology, 18 and other support. 19 The fundamental purpose of rocky desertification control is to maintain the limited soil and 20 water resources, restore the vegetation and ecological environment, promote economic 21 development, and help peasants out of poverty. With the development of China's economy, 22 peasants' standards of living have greatly improved. Merely aspiring to feed and clothe 23 themselves, they now aspire to earn greater income. For this reason, economic benefits have 24 become decisive factors for their production activities. At present, peasants' income from 25 rocky desertification control mainly comes from planting cash crops and from subsidies for 26 converting farmland to forest and grassland. However, peasants are likely to give up the 27 management of desertification control when they receive insufficient income due to 28 fluctuations in market prices (which easily affect benefits given from planting cash crops), 29 low subsidies, and short compensation times. Therefore, the socio-economic factors that cause In short, rocky desertification control is not only a scientific issue, but also a household 3 livelihood issue (Wang and Li,2007), which should be addressed with governance methods 4 and technologies, as well as design of policies and public participation. Such an approach is 5 imperative for future rocky desertification control initiatives.

To improve ecological compensation policies and establish coordination 23 mechanisms of multistakeholders in rocky desertification control 24
The household livelihood concerns of peasants have changed from maintaining livelihood 25 security to pursuing higher profits. However, with more and more attention being paid to the 26 effects of rocky desertification control on improving local ecosystem services, the private 27 goods function of rocky desertification control is decreasing while its function as a public 28 goods is increasing. Therefore, the biggest beneficiaries of rocky desertification control are 29 the users of the products, not just the peasants. But as the implementers of rocky 30 desertification control, peasants' prime consideration is their own utility maximization which 31 is not equal to the overall utility maximization. Therefore, the evaluation standards for utility 32 maximization of rocky desertification control should be made on the basis of all users of the 1 products, not just the peasants. In order to achieve the goal of utility maximization of rocky 2 desertification control, ecological compensation should be provided for participant peasants 3 and appropriately increased with the development and inflation of socio-economy. In order to 4 achieve the sustainability of the joint action of various multistakeholders, to clarify the needs 5 of various participants, and to move away from sole government management, a rational 6 coordination mechanism must be established to coordinate the interests of various participants. 7 In order to coordinate the interests of various multistakeholders and achieve the economic, 8 social, and ecological benefits of rocky desertification control, we should attempt to establish 9 a management mechanism based on integrated ecosystem management methods. the structure and complexity of trophic levels, and particularly litter production and turnover. 20 According to the different degrees of rocky desertification and control objectives in different 21 types of karst geomorphology, we should correspondingly select appropriate reference 22 ecosystems for evaluation and set up a relatively complete evaluation system. In the 23 construction of the evaluation index system, except for directly considering economic benefits, 24 we should also consider the different impacts of rocky desertification control on ecological 25 security and ecological service functions, so as to establish reasonable ecological 26 compensation standards and follow-up governance policies. It should be noted that economic 27 values are not natural attributes of the ecosystem but are closely associated with the number 28 of beneficiaries and their socio-economic background. That also implies that, in general, the 29 balance of ecosystem values in a certain region can only be extrapolated to those in similar 30 regions; otherwise, adjustments must be made. In addition, ecosystem restoration is a slow 31 and dynamic process, and there are significant uncertainties for ecosystem development in the 32 recovery process (Bark et al.,2013). Thus, dynamic monitoring of rocky desertification 1 control is conducive to identifying the problems and taking timely corrective measures. 2

To strengthen research on key recovery technologies of ecological service function 3 and supporting technologies 4
The special geological and ecological environment poses a great challenge to the restoration 5 of degraded ecosystems in karst areas (Gillieson et al.,1996). With regard to research on 6 ecological service function recovery technologies in degraded ecosystems in karst areas, we 7 should focus on specific experimental verification techniques of ecological restoration based 8 on different types of geography and climate zones. Since it is difficult to spontaneously 9 recover the structure and functions of a degraded karst ecosystem, (such as the storage 10 capacity of epikarst, land productivity, and the natural resilience of vegetation), we should 11 also focus on studying the vital supporting technologies of rocky desertification control, such 12 as storage technology for surface water resources, exploitation and utilization technologies for 13 underground water resources, the selection and breeding of special economic and ecological 14 recovery plants, and optimal configuration technologies and models of adaptive plant 15 communities. Furthermore, karst ecosystems are fragile and very sensitive to changes in the 16 surrounding environment. 17

Conclusions 18
Soil and water conservation in karst ecosystems is one of the fundamental goals of rocky 19 desertification control and is the foundation of local, social, and economic development, 20 especially for peasants. In the process of vigorously implementing rocky desertification 21 control, we must pay close attention to the following two facts: first, the environmental 22 consequences of the same human activities in the karst area in Southwest China are far 23 heavier than that in similar climate zones because of its special geological and ecological 24 environment; second, the resilience of karst ecosystems is far lower than that in similar 25 climate zones, and so it is very difficult for the ecological system to recover from destruction 26 caused by unreasonable human activities. Thus, in order to improve rocky desertification 27 control, we should focus more on eliminating the anthropic factors causing rocky 28 desertification in institutions, policies and economy, and on strengthening preventative 29 measures for ecological degradation. In particular, we must deviate from the existing 30 administrative department framework, which has been divided according to ecosystem 31 elements (e.g. the Forestry Bureau is responsible for forests and the Water Resource Bureau is 32 responsible for water loss and soil erosion), and create policy frameworks that reflect 1 administrative divisions. More importantly, we should formulate regulations and policies 2 according to ecosystem integrity and geographical regions in order to improve this ubiquitous 3 phenomenon, since governance management of rocky desertification control so far has not 4 been that successful. 5 In addition, climate warming has severely affected karst ecosystems, such as water resources 6 (Lian et al.,2015; Thomas et al.,2016). Climate warming has an impact on regional 7 precipitation, evaporation and runoff. Besides, it will increase extreme weather events, such 8 as heavy rainfall, high temperature and drought, ect, coupled with surface water serious 9 seepage, easily leading to regional vegetation degradation and the increase of soil erosion. 10 Therefore, we should strengthen research on the impact of global climate change on rocky 11 desertification control. 12 Data availability: the data of Table 1