Ding Ma

Ph.D Student

Working Paper

  1. “Hot and Cold Choices: The Role of Extreme Temperatures in Shaping Industrial Geographical Distribution” (with Min Wang, Shuo Li and Xiumei Yu) [SSRN] Climate change
    • R&R at Journal of Environmental Economics and Management
    • Presentations by co-authors: The 9th CCER Summer Institute (Peking University, 2025); The 4th Annual Conference of CAERE (Shanghai University of Finance and Economics, 2025)
    [Abstract]This paper examines how extreme temperatures shape firm entry decisions and industrial geography. Leveraging comprehensive firm registration data from China, we identify an inverted U-shaped relationship between temperature and firm entry, while firm exit remains largely unresponsive. Sector analyses reveal that temperature extremes suppress firm entry in agriculture and industry through production shocks, and in services through demand-side spillovers. Firms also adapt by shifting equity investments toward new firm establishments in regions with milder climates. Climate projections indicate that ongoing warming will significantly reshape industrial geography, with warmer regions experiencing greater losses. These findings highlight firm location choice as a critical channel of climate adaptation and underscore the role of temperature risk in driving long-term spatial economic change.
  2. “Extreme Temperatures Promote High-Fat Diets” (with Shuo Li, Xi Chen and Jintao Xu) [medRxiv] Climate change Health
    • Excellent Paper Award, The 6th China Health Economic Development Forum, 2023
    • Presentations by co-authors:The 9th CCER Summer Institute (Peking University, 2025); The 4th Annual Conference of CAERE (Shanghai University of Finance and Economics, 2025); The 6th China Health Economic Development Forum (Wuhan University, 2023)
    [Abstract]Extreme temperatures threaten agriculture and exacerbate global food insecurity, yet their direct impact on dietary choices remains poorly understood. We provide the first evidence of how short-term exposures to hot or cold weather may affect macronutrient intake in China. We find that hot weather reduces carbohydrate and protein consumption but not fat intake, while cold weather increases all nutrient intakes, particularly fats. Both conditions elevate high-fat diet risks. Fans, air conditioners, and heating systems mainly mitigate these effects by altering thermal comfort, whereas refrigerators, which primarily serve to store food, show minimal impact. These results suggest that temperatures may influence dietary patterns more through physiological appetite regulation than food accessibility. Socioeconomic disparities are evident, with rural and less-educated individuals more likely to adopt high-fat diets. Projections indicate that climate change will generally increase high-fat diet probabilities, with northern regions experiencing declines and southern regions rising due to differing temperature changes.
  3. “Environmental Health Benefits of Public Infrastructure: Evidence from Tap Water and Water Pollution in China” (with Shuo Li and Jintao Xu) Environment Health
    • Excellent Paper Award, The 7th China Health Economic Development Forum, 2024
    • Excellent Paper Award, The 8th Annual Meeting of the China Labor Economists Forum, 2024
    • Presentations: Chinese Economists Society (CES) Annual Conference (Zhejiang University, 2024); The 8th CCER Summer Institute (Peking University, 2024); The 8th Annual Meeting of the China Labor Economists Forum (Shanghai University of Finance and Economics, 2024); The 21st Seminar of Chinese Women Economists (Wuhan University, 2024)
    • Presentations by co-authors: China Economics Annual Conference (Peking University, 2024); The 7th China Health Economic Development Forum (Sichuan University, 2024); The 5th Workshop on Resource Security and Economic Sciences (Xiamen University, 2024)
    [Abstract]Based on data from the China Health and Nutrition Survey and Surface Water Quality Weekly Report, we estimate the effects of water pollution, tap water, and their interaction on individual health status. Using the panel IV regression method, we find that water pollution significantly increases the morbidity rate, while ignoring the different levels of pollution exposure caused by the use of tap water may lead to a serious underestimate of the impact of water pollution. Regression results show that tap water can offset about 60% of the negative health effects of water pollution, and the non-offsetting part may come from pollutants that cannot be eliminated by treatment processes in waterworks. Finally, comparing the disease cost and the total health cost caused by water pollution, we find that nearly 2/3 of the health cost can be attributed to the disease cost. As one of the most important infrastructure investments, the adoption of tap water greatly eliminates the negative impact of water pollution on the health of Chinese residents. This has important general implications for low-income countries with a low proportion of tap water supply worldwide.
  4. “Temperature-Dissolved Oxygen Relationship Challenges Water Quality Management Under Climate Change” (with Shuo Li and Jintao Xu) Environment
    5. [Abstract]Climate change presents critical environmental challenges including water quality management. Surface water quality in China, measured using different indicators, has improved over the years. However, seasonality patterns across key water quality indicators are contradictory. While dissolved oxygen (DO) concentration reaches its worst levels in late summer, other major indicators, such as permanganate index (CODMn) and ammonia nitrogen (NH3-N), show opposite trends. Through regression analysis, this study reveals a strong negative relationship between DO concentration and air temperature, explaining the seasonal contradictions observed across key water quality indicators. Higher air temperatures lead to an increase in water temperature, thereby reducing the DO concentration in water. Since this temperature–DO concentration relationship is primarily a physical rather than a chemical process, current water quality assessments in China may be biased, particularly under warmer conditions, potentially overestimating water pollution severity and influencing environmental policy decisions. Similar challenges with water‑quality management also exist globally. Therefore, we recommend selecting metrics that match each specific water‑use purpose. Drinking water standards should rely on DO saturation, whereas DO concentration should be retained for criteria that protect aquatic biodiversity. Our findings emphasize the interplay between climate change and water quality management, providing critical insights to achieve Sustainable Development Goals (SDGs) and advance integrated environmental management strategies.

Publication in Chinese

  1. Ding Ma and Shuo Li*. “Trends in China’s surface water quality and control policy solutions”. China Population, Resources and Environment, 2023,33(05):27-39.
    2. 马丁,李硕 (通讯作者).中国地表水水质变化趋势及治理政策应对[J].中国人口·资源与环境, 2023,33(05):27-39.
  2. 马丁. 埃塞俄比亚外汇管制问题分析.《冲突与发展：埃塞俄比亚政治、经济与社会研究》第七章, 待出版.