The bibliometric data utilized to compute the citation-based metrics for this ranking were systematically collected on January 12, 2026. A cornerstone metric for establishing a scientist’s position within the ranking is the D-index (Discipline H-index). Unlike the traditional H-index, the D-index is discipline-specific, compiling publications and citations exclusively within the examined field—Environmental Sciences in this case—ensuring the ranking precisely reflects expertise and impact in the relevant domain.
Scope of Research and Inclusion Criteria
This ranking was developed through a rigorous examination of 279,971 scientist profiles drawn from a broad spectrum of bibliometric sources across all academic disciplines. From this extensive dataset, a focused group of 1,431 scientists with research primarily in Environmental Sciences was identified and assessed.
To qualify for inclusion, a scientist was required to have a minimum D-index of 30, with a majority of their tier publications concentrated in Environmental Sciences. Additionally, significant awards and recognitions in the field were considered to ensure holistic evaluation. The D-index threshold is calibrated dynamically in increments of 10 relative to the size of each discipline’s scholarly population, thereby guaranteeing inclusion of the top 1% of leading experts within Environmental Sciences.
Furthermore, to ensure close alignment between overall scholarly impact and discipline-specific expertise, a maximum proximity of 30% was maintained between a scientist’s general H-index and their D-index. This criterion supports the emphasis on recognized specialization within Environmental Sciences.
Verification and Validation Processes
We acknowledge that raw bibliometric data alone cannot fully capture the qualitative aspects of scholarly output. Accordingly, every scientist profile included in this ranking underwent meticulous manual verification. Cross-correlation against publications indexed in a variety of respected journals, conference proceedings, and other authoritative sources was performed to confirm accuracy and relevance.
Although not directly contributing to the ranking position, the number of publications in prominent and peer-reviewed journals serves as an important secondary indicator of a researcher’s contribution to advancing knowledge within Environmental Sciences.
The ranking position relies exclusively on the D-index derived from OpenAlex and CrossRef data, leveraging their status as the preeminent and most reliable bibliometric databases accessible to researchers worldwide.
For a detailed overview of the complete methodology employed, we invite you to consult our methodology page.
Research.com’s Mission and Vision
At Research.com, our mission is to empower researchers, academic institutions, policymakers, and organizations globally to visualize the trajectories and accomplishments of leading scientists. This ranking serves as a transparent and rigorous tool to identify and celebrate top experts in Environmental Sciences, whether on a national scale within Tunisia, across countries, or within specific research institutions.
By doing so, we aim to foster collaboration, inspire excellence, and inform strategic decision-making processes that advance scientific innovation and societal progress. The careful and meticulous approach underlying the creation of this ranking reflects our commitment to integrity, accuracy, and meaningful impact within the academic and research communities.
