Income diversification and family welfare of small-scale households differ between agricultural and pastoral zones in Xizang, China

Livelihood diversification is an effective strategy for maintaining household welfare under conditions of vulnerability. However, a comprehensive evaluation of their effects, determinants, and mechanisms on livelihood diversification and household welfare remains lacking in Xizang. This research used datasets on averages, trend, and variability of mean annual temperature, mean annual precipitation, and normalized difference vegetation index (NDVI) to assess vulnerability context. Data on livelihood sub-capitals, disposable income, and daily expenditure were collected using semi-structured questionnaires, with 796 small-scale households randomly selected from agricultural (215), agro-pastoral (278), and pastoral (303) zones. Zonal cross-variances in livelihood capital, income diversification, and household welfare were examined using one-way analysis of variance. Meanwhile, their interrelationships and influential pathways were further explored using bivariate regression, Pearson correlation with Mantel test, and piecewise structural equation modelling. Our results indicated that income diversification is highest in the pastoral (0.51), followed by the agro-pastoral (0.44) and agricultural zones (0.29, p < 0.001). Household welfare peaks in the agro-pastoral zone (0.23), followed by the agricultural (0.17) and pastoral (0.13) zones ( p < 0.001). Income diversification positively influences welfare levels among agro-pastoral households across all zones. Mean annual temperature directly influences household welfare in agro-pastoral and pastoral zones. Meanwhile, Mean annual precipitation, NDVI, and mean annual precipitation trendindirectly affect income diversification via shifting human and physical capitals, with these indirect pathways varying across zones. Therefore, it suggests that policymakers should assess bioclimatic conditions and capital allocations to tailor interventions to meet region-specific needs, and that focusing on factors that motivate households to diversify their livelihoods is essential for developing targeted interventions.