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With the deepening of global change research, the applied problems such as global change risk and response for social sustainable development, temporal and spatial allocation of resources and environmental elements and impact assessment of ecosystem are becoming a new trend in the research field of global change. Based on the ecological framework, we focused on clarifying the connotations of resources and the environment and their components. Resources refer to all substances consumed by organisms in the process of producing organic matter from inorganic matter and transferring energy and matter among organisms. These include inorganic resources ( e.g. , solar radiation, CO 2 , O 2 , water, and mineral elements) and organic resources (as a source of food for other organisms). In contrast, the environment can not be consumed or depleted by organisms. In addition, we described the components of global change and the associated variations of resources and environmental factors, as well as current research progress on the responses of ecosystem to global change. We scientifically described the processes and mechanisms of global change in terms of their influence on resources, the environment, and ecosystems within a theoretical framework based on ecological principles. Our goal was to provide a strong theoretical foundation for future research on coping with the risks of global change.

The value evaluation of endangered species can provide important supports for policy-making in biodiversity conservation. We evaluated the stakeholders' preference and willingness to pay (WTP) from the perspective of stakeholders by the choice experiment method (CEM) and discussed the ecological compensation mechanism, with Elaeagnus mollis , a national secondary key protected plant as an example. Based on the interest demands analysis of three stakeholders, the management departments, enterprises and farmers, we measured five species attributes of E. mollis , including planting area, product classification, seedling varieties, protection investment, and far-mers' income. Furthermore, the preference of stakeholders and WTP for different attribute variables were analyzed using random parameter model (RPL). The results showed that the preference of respondents for the variable of "increase investment in protection" was the strongest and WTP was the highest (331.00 yuan·a -1 ·household -1 ). The stakeholders had stronger preference for the variables of "simultaneous development of high and low-end products" and "development of high-end products", with WTP being 242.71 and 227.57 yuan·a -1 ·household -1 , respectively. For the variables of "farmers' income", "unchanged investment in protection", "seedling varieties" and "planting area", stakeholders showed certain preference and WTP from strong to weak. The prefe-rence for "no investment in protection" and "development of low-end products" was weaker and the WTP was negative. Through direct and indirect approaches of compensation, ecological compensation could be implemented for the objects of ecological compensation ( E. mollis and associated habitat). The value of compensating surplus (CS) calculated was 285.62 yuan·a -1 ·household -1 .

As one of the important pathways of material and energy flow between plant and soil system, litterfall plays a key role in the process of vegetation and soil restoration in ecologically fragile region. To explore the inter- and intra-annual dynamics of litter production and related regulatory factors at different habitats in sandy land ecosystem, we investigated the litter production during nine continuous growing seasons, while the air temperature and precipitation were measured over mobile dune, fixed dune, and grassland in Horqin Sandy Land. The results showed that annual litter production at different habitants were in the order of mobile dune (9.01 g·m -2 ) ＜ fixed dune (67.46 g·m -2 ) ＜ grassland (119.55 g·m -2 ). The inter-annual dynamics of litterfall fluctuated significantly, with a double-peak curve in fixed dune and "W" curve in grassland. The intra-annual variation of litterfall exhibited a "U" curve at all the three habitats, with peaks appearing in April and September, respectively. Precipitation and temperature had significant effects on the intra-annul dynamics of litterfall production in fixed sand dune and grassland, but had no significant effect on the inter-annual dynamics of litter production at three habitats. Temperature was the major factor affecting the dynamics of the litter fall during the growing season in Horqin Sandy Land.