本研究運用固定效應門檻迴歸模型，探討整體環境績效及其子構面（包括溫室氣體排放、能源管理、用水量與廢水管理、廢棄物與有毒物質管理）與公司績效之間的非線性關係。研究結果顯示，對於高污染產業（碳密集度高於該產業一半以上的上市櫃公司），提升整體環境績效、減少碳排放以及用水量，均顯著提升公司的會計績效，然而，Covid-19疫情爆發後，此效果有所削弱，僅剩減少碳排放仍具有顯著影響。此外，即便公司不屬於高污染產業，若其減碳表現不佳（碳密集度高於該產業一半以上的上市櫃公司），提升整體環境績效、減少碳排放及用水量仍可增加公司的會計績效，且此效果並未因Covid-19的影響而改變。另一方面，廢棄物與有毒物質管理對公司市場績效的影響尚不明確，在揭露廢棄物處理相關資訊時，企業需謹慎評估其對投資者觀感的影響，否則可能導致公司市場績效下降。最後，建議減碳表現不佳的企業應迅速制定環境績效提升策略，積極降低碳排放及進行水資源管理，否則可能面臨產品市場競爭力下降的風險，導致公司整體績效下降。

This study employs a fixed-effect threshold regression model to investigate the non-linear relationship between overall environmental performance and its sub-dimensions (including greenhouse gas emissions, energy management, water usage and wastewater management, and waste and hazardous substance management) and corporate performance. The findings reveal for high-pollution industries (with carbon intensity above the median of all listed companies) that improving overall environmental performance, reducing carbon emissions, and lowering water usage significantly enhance accounting performance. However, after the outbreak of the COVID-19 pandemic, these effects weakened, with only the reduction of carbon emissions remaining significantly impactful. Even for companies not categorized as high-pollution industries, if their carbon reduction performance is poor (carbon intensity above the median of their respective industries), then enhancing overall environmental performance, reducing carbon emissions, and lowering water usage still significantly improve accounting performance. These effects did not change with the impact of COVID-19. On the other hand, the impact of waste and hazardous substance management on market performance remains unclear. When disclosing information related to waste treatment, companies should carefully assess its potential impact on investors’ perceptions, as it may lead to a decline in market performance. Finally, companies with poor carbon reduction performance are strongly recommended to develop strategies to improve environmental performance, actively reduce carbon emissions, and strengthen water resource management. Failure to do so may decrease product competitiveness in the market and lead to poor overall corporate performance.

門檻迴歸模型;環境績效;公司績效

Threshold Regression; Environmental Performance; Corporate Performance