{"title":"Factors that are strongly causal to NPP across diverse climate regions in China","authors":"Kaizhi Liu, Lianghui Tian, Weilin Wang, Yuanyuan Meng, Liangxia Duan, Hongxia Xie","doi":"10.1016/j.indic.2025.101033","DOIUrl":null,"url":null,"abstract":"<div><div>While Net Primary Productivity (NPP) driving mechanisms have been widely studied through correlation analysis, precisely quantifying causal relationships remains challenging. This study investigates causal effects of climatic and topographic factors on NPP across five Chinese climatic regions using Geographic Convergent Cross Mapping (GCCM). Our results reveal several strong-causality-yet-weak-correlation patterns: terrain relief with NPP in SE and NE China; DEM in SW and SE China; and sunshine radiation in SW and SE China. Crucially, we identify optimal operative intervals for these causal factors: DEM (511–607 m), terrain relief (22–128 m), temperature (16.2–18.1 °C), and sunshine radiation (1.24–1.36 × 10^7 J/m<sup>2</sup>). By integrating GCCM with Geodetector analysis, we further uncover the underlying mechanisms, demonstrating topography's role as an integrator in ecosystem processes. These insights provide valuable scientific support for optimizing NPP modeling parameters and formulating regional ecological restoration strategies.</div></div>","PeriodicalId":36171,"journal":{"name":"Environmental and Sustainability Indicators","volume":"29 ","pages":"Article 101033"},"PeriodicalIF":5.5000,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Environmental and Sustainability Indicators","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2665972725004544","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2025/11/27 0:00:00","PubModel":"Epub","JCR":"Q1","JCRName":"ENVIRONMENTAL SCIENCES","Score":null,"Total":0}
引用次数: 0
Abstract
While Net Primary Productivity (NPP) driving mechanisms have been widely studied through correlation analysis, precisely quantifying causal relationships remains challenging. This study investigates causal effects of climatic and topographic factors on NPP across five Chinese climatic regions using Geographic Convergent Cross Mapping (GCCM). Our results reveal several strong-causality-yet-weak-correlation patterns: terrain relief with NPP in SE and NE China; DEM in SW and SE China; and sunshine radiation in SW and SE China. Crucially, we identify optimal operative intervals for these causal factors: DEM (511–607 m), terrain relief (22–128 m), temperature (16.2–18.1 °C), and sunshine radiation (1.24–1.36 × 10^7 J/m2). By integrating GCCM with Geodetector analysis, we further uncover the underlying mechanisms, demonstrating topography's role as an integrator in ecosystem processes. These insights provide valuable scientific support for optimizing NPP modeling parameters and formulating regional ecological restoration strategies.