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Multiple types of global change processes increasingly impact rural development programs; the interplay between these processes can impact rural livelihoods in unforeseen and surprising ways. To date, most of the studies examining farmers’ risk perceptions and risk management strategies have been agriculture-focused with little attention to their livelihood system. This study introduces the framework of the sustainable livelihood approach (SLA) to examine farmers’ risk perceptions and the risk management strategies of smallholder households in rural China. Based on data collected from a sample of 540 smallholder households, we used descriptive statistics for analyzing and classifying risk sources and risk management strategies. A multinomial logistic regression model is employed to explore the role of livelihood assets in farmers’ preferred risk management strategies. The results find that farmers express higher levels of concern about educational risk, health risk and employment risk. They put mo...

Plantations can significantly improve the ecological environment of arid areas. However, in the arid area of Northwestern China, plantations consume several thousand cubic meters of water per hectare per year, which also has a negative effect. By evaluating the relationship between the supply and demand of ecosystem services, the positive and negative benefits of plantations can be effectively identified for regional sustainable development. This study took typical arid regions as examples and evaluated the changes in ecosystem services before and after the conversion of a desert shrub system to a plantation system based on emergy analysis. The relationship between the supply and demand of various ecosystem services from different stakeholder perspectives was investigated and combined with the degree of ecosystem service demand obtained from the participatory survey. Results showed the following. (1) The ecosystem services provided by vegetation increased, the ecosystem services provided by water resources decreased, and the total service decreased by 6.89E+17 sej. (2) The relationship between the supply and demand of ecosystem services provided by water resources was of the "low-high" type. Dust purification was of the "high-high" type, and carbon sequestration and soil conservation were of the "high-low" type. (3) From the perspective of citizens, the matching degrees of the supply and demand of dust purification and soil conservation services were 21.75% and 9.38% higher than those of farmers, respectively. From the perspective of farmers, the matching degrees of the supply and demand of water supply, water purification, power supply and sediment transport, and carbon sequestration were 9.90%, 10.96%, 3.22%, and 18.28% higher than those of citizens, respectively. In summary, attention should be given to the efficient use and conservation of water resources and the promotion of the coordinated development of ecosystem services by comparing the differences in matching degrees of supply and demand among different stakeholders when constructing plantations. Meanwhile, the distribution of water resources should be given attention to protect the water demand of citizens in a targeted manner for effectively improving the level of regional well-being.

Livelihood is a complex system that includes environmental, economic, social, and institutional dimensions, driving the evolution of the relationship between individuals and geographical environment. Further research on how people value and envision their livelihoods may help to better develop plans and incentives aimed at protecting and restoring ecosystem services. Therefore, it is necessary to understand the current livelihoods status of local households, to identify underlying factors that affect their current and future livelihood strategy, thereby providing policy references for grassland optimization and the sustainable development of pastorists’ livelihoods. In this study, researchers collected data by surveying 427 households from the Hulunbuir grasslands of China. We find that the pastoral livelihood strategies currently are dominated by pastoral husbandry (pure pastoral husbandry or dominant pastoral husbandry) and supplemented by concurrent household occupations (dominant non-pastoral husbandry and non-pastoral husbandry); the households' future livelihood strategy is mainly to expand pastoral husbandry. Our analysis shows again, livelihood asset possession has a significant influence on pastoral families' current and future choices of livelihood strategies. In particular, the ownership of social assets, geographical advantage, and 'production assets', which consist of natural, physical, and financial assets, have significant influences on pastoral households' current livelihood strategy but non-significant impacts on their future livelihood strategy. Human assets and informational assets significantly influence both current and future livelihood strategies of pastoral households. We emphasize that livelihood assets can be the entry point for policies aiming to linking sustainable livelihoods with sustainable grassland use and conservation, particularly at a regional level.

Accurately identifying the functional orientation of the different components of a circular agricultural (CA) system is crucial for improving the ecological efficiency of the system. However, the functional orientation still needs more in-depth quantitative analysis. This study serves as a feasible way of solving this problem. An energy flow model has been developed based on the Odum Energy System Language, which is a method based on mathematics, energy flows, cybernetics and hierarchical relationship and can effectively modelling the agriculture resources recycling and environmental impact. The case study of the CA system of Fuqing Xingyuan Company has been conducted, quantitatively analyzing the functional orientation differences between different components in the CA system. The results showed that: (1) The dragon fruit planting system benefited from recyclable resources, but did not contribute recyclable resources, and was positioned as a “beneficiary system”. If the planting amount of the dragon fruit increasing by 10% (Scenario 1), the resources allocation would be unbalanced, and the total economic output of the CA system would reduce by 0.17% annually; otherwise, it would increase by 0.29% (Scenario 2); (2) The pig breeding system drove the overall operation of the system and provided recyclable resources for other components, and was position as “drive system”. If the breeding amount increases by 10% (Scenario 3), the pig breeding system would increase the recyclable resource input of the CA system, and the total economic output of the CA system would rise and fluctuate, increasing by 0.20% annually. Otherwise, the average annual reduction would be 0.59% (Scenario 4). The changing trend of the economic output under different scenarios supported the results of functional orientation analysis. It provides an effective way to identify the functional orientation of different components in a CA system based on the Energy System Language.

Studying the responses of soil respiration (R s) to soil management changes is critical for enhancing our understanding of the global carbon cycle and has practical implications for grassland management. Therefore, the objectives of this study were (1) quantify daily and seasonal patterns of R s, (2) evaluate the influence of abiotic factors on R s, and (3) detect the effects of soil management changes on R s. We hypothesized that (1) most of daily and seasonal variation in R s could be explained by soil temperature (T s) and soil water content (S w), (2) soil management changes could significantly affect R s, and (3) soil management changes affected R s via the significant change in abiotic and biotic factors. In situ R s values were monitored in an agropastoral ecotone in Inner Mongolia, China, during the growing seasons in 2009 (August to October) and 2010 (May to October). The soil management changes sequences included free grazing grassland (FG), cropland (CL), grazing enclosure grassland (GE), and abandoned cultivated grassland (AC). During the growing season in 2010, cumulative R s for FG, CL, GE, and AC averaged 265.97, 344.74, 236.70, and 226.42 gC m−2 year−1, respectively. The T s and S w significantly influenced R s and explained 66%–86% of the variability in daily R s. Monthly mean temperature and precipitation explained 78%–96% of the variability in monthly R s. The results clearly showed that R s was increased by 29% with the conversion of FG to CL and decreased by 35% and 11% with the conversion of CL to AC and FG to GE. The factors impacting the change in R s under different soil management changes sequences varied. Our results confirm the tested hypotheses. The increase in Q 10 and litter biomass induced by conversion of FG to GE could lead to increased R s if the climate warming. We suggest that after proper natural restoration period, grasslands should be utilized properly to decrease R s.

An extended auxiliary function method is presented for constructing exact traveling wave solutions to nonlinear partial differential equations. The main idea of this method is to take full advantage of the solutions to the elliptic equation to construct exact traveling wave solutions for nonlinear partial differential equations. mKdV equation is chosen to illustrate the application of the extended auxiliary function method. Consequently, more new exact traveling wave solutions are derived that are not obtained by the previously known methods.

This paper proposes a practical public key encryption scheme which is provable chosen cipher text(CCA) secure based on the gap computational linear Diffie-Hellman assumption in the standard model. This is the first CCA secure scheme based on the gap computational linear Diffie-Hellman assumption. This scheme is efficient and the proof of the security is tight. We also reduce the size of the public key from $n$ to $2\sqrt{n}$ based on the twin gap computational linear Diffie-Hellman assumption. And the time for encryption and decryption is significantly reduced. And we point out that a generalization of the scheme can be constructed similarly based on the gap $k$-computational linear assumption.

Extended tanh q function expansion method is proposed, and applied to construct the explicit exact solutions of a class of the nonlinear evolution equation. Many new explicit soliton solutions are obtained by this method. The Method is applied to other nonlinear evolution equations.

A extended elliptic function expansion method is presented, which is a direct and unified algebraic method for constructing multiple and more general travelling wave solution for nonlinear partial differential equation and implemented in a computer algebraic system. The proposed method is applied to consider Zakharov equation and obtains rich new families of the exact solutions.