With the increase of residents’ requirements for the living environment, the current indoor thermal environment cannot meet the needs of modern rural residents who live in the northeast of Sichuan, China. Passive energy-saving strategies can not only improve the thermal performance of envelopes but also create high economic benefits. Evaluating the application effect of passive energy-saving strategies for traditional dwellings can provide a guide for local residents and policy-makers to select rational passive strategies. Seven energy-saving strategies are proposed based on the current local building construction and heat transfer model, and then their energy-saving potential is evaluated by using EnergyPlus and the dynamic investment payback period method. Results show that adding exterior envelope insulation and setting on-top sunspaces on the roof simultaneously can save 83.9% of building energy consumption. But the most economic energy-saving strategy is only employing exterior envelope insulation for local traditional dwellings when considering the economy. It can save 842 CNY/m2 during 100 years and its dynamic investment payback period is 14.1 years. In addition, building orientation also affects the energy-saving effects and the energy-saving rate can be increased by 8.4% under the optimal orientation (facing south) compared with the worst orientation (facing west).

Aims The alpine meadow ecosystem in Tibet is fragile and sensitive, and its carbon sink function with respect to climate change has become a matter of widespread concern. Therefore, this study aims to clarify the inter-annual variations (IAVs) in the carbon fluxes in an alpine meadow and further quantify the contributions of the driving factors to the IAVs. Methods Based on seven years of flux data (2012–2018) and the corresponding climatic and biotic data, a set of look-up tables (LUTs) was used to separate and quantify the IAV sources. Furthermore, linear perturbation analyses were employed to quantify the contributions of each key factor. Important Findings During 2012–2018, the net ecosystem productivity (NEP), gross primary productivity (GPP) and ecosystem respiration (Re) of this alpine meadow were 3.31±26.90, 210.18±48.35 and 206.88±28.45 g C m –2 y –1, respectively, which indicate relatively large IAVs. When the contributions of climatic and biotic effects were distinguished and quantified, the dominant effects of biotic factors emerged. Additionally, negative interactions between climatic and biotic effects were detected. Among the climatic factors, only soil water content (SWC) contributed relatively more to the IAVs and played a role in regulating the interactions between climatic and biotic effects. These results suggest that biotic effects must be carefully considered to reduce the uncertainties associated with future carbon flux estimates.

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