Objective Against the backdrop of China’s ecological civilization construction and comprehensive green transition, the national strategy of “synergistic promotion of carbon reduction, pollution reduction, greening expansion, and growth” has become a core policy orientation. How to foster effective synergies among these four objectives—carbon reduction, pollution reduction, greening expansion, and growth—have consequently emerged as a key research agenda across multiple disciplines. As the primary research object of landscape architecture, green space constitutes a crucial spatial carrier for “greening expansion” and offers a distinctive spatial planning and design perspective for simultaneously advancing carbon reduction, pollution mitigation, and high-quality development. This study aims to clarify the policy evolution, disciplinary research patterns, and spatial mechanisms underlying such synergies, and to explore how landscape architecture can contribute more systematically to this national strategic framework.

Methods The study first reviews major national policies issued since 2005 that relate to carbon reduction, pollution control, ecological conservation, greening expansion, and green growth. It outlines their advancement pathways, summarizes evolving objectives and conceptual connotations, and identifies linkage mechanisms among “carbon reduction, pollution reduction, greening expansion, and growth”. Second, based on literature statistics and disciplinary mapping, the study examines publication trends and disciplinary distribution of collaborative research focusing on different combinations of these four goals, thereby revealing the dominant paradigms and existing gaps. Third, from the standpoint of landscape architecture, it analyzes how different forms and configurations of “greening expansion” can be leveraged to achieve synergistic improvements across carbon reduction, pollution mitigation, and economic growth, with particular attention to spatial characteristics, ecological processes, socioeconomic feedbacks, and the translation of scientific findings into planning, design, and management strategies.

Results 1) The relationships among carbon reduction, pollution reduction, greening expansion, and growth are strongly shaped by successive rounds of policy guidance. With the institutionalization of ecological civilization and the proposal of the “dual carbon” targets, policy documents have gradually shifted from sectoral management to integrated, cross-sectoral governance. During 2022−2025, China has entered a stage of deepening policy coordination, in where the four targets are no longer pursued in isolation but are embedded in systematic frameworks for territorial spatial planning, environmental management, and industrial restructuring. 2) As of 2025, the academic literature still focuses predominantly on pairwise synergies: carbon reduction−growth, pollution reduction−growth, greening expansion−carbon reduction, greening expansion−pollution reduction, greening expansion−growth, and carbon reduction−pollution reduction. Studies simultaneously addressing three or more objectives remain relatively scarce. Publications are heavily concentrated in environmental science and engineering, energy and climate studies, economics, and public policy. These works are largely driven by top-down policy agendas and oriented toward macro-level assessment, scenario simulation, and policy evaluation. In contrast, there is a clear deficiency of research within human settlement and built environment disciplines—including landscape architecture, urban and rural planning, and architecture—that take spatial localization, spatial configuration, and site-scale intervention as core entry points. 3) From the perspective of landscape architecture, existing studies primarily focus on how the spatial characteristics of green spaces—such as area and scale, type composition, landscape pattern, connectivity, configuration, and functional zoning—affect carbon sequestration, pollutant removal, microclimate regulation, and socio-economic benefits. These studies translate such relationships into principles that inform green space planning, design, and management. Current evidence demonstrates that “greening expansion” can effectively contribute to carbon reduction (e.g., through vegetation carbon sinks, reduced building energy consumption, and promotion of low-carbon mobility), pollution reduction (e.g., through air and water purification, noise mitigation, runoff regulation, and alleviation of urban heat islands), and growth (e.g., through enhancement of property values, attraction of investment, promotion of recreation and tourism, improvement of public health, and support for green industries and employment).

Conclusion It is necessary to further strengthen multidimensional synergy research led by “greening expansion” under the disciplinary framework of landscape architecture, with spatial planning and design as a primary leverage. Future work should move beyond isolated pairwise relationships and pay greater attention to multi-objective coupling mechanisms that integrate carbon reduction, pollution control, ecosystem restoration, and high-quality development. Specifically, green space planning should be more closely aligned with the hierarchical management requirements of territorial spatial planning, coordinating national, regional, urban-rural, and site-specific scales. Taking synergistic carbon and pollution reduction, as well as integrated “carbon reduction-pollution reduction-growth” goals, as core targets, research should develop systematic strategies for green space planning, design, and management that cover multiple spatial levels, including “urban−rural systems, space types, plots”. This implies establishing quantitative indicators and spatial configuration guidelines for different categories of green space; embedding ecosystem service optimization, low-carbon transition objectives, and environmental health considerations into zoning, layout, and design codes; and strengthening adaptive management based on continuous monitoring, performance assessment, and feedback adjustment. By leveraging the spatial carrier function of green spaces and integrating ecological, social, and economic objectives coordinated, landscape architecture can play a pivotal role in realizing the synergy of carbon reduction, pollution mitigation, greening expansion, and sustainable growth, providing spatial solutions, design pathways, and technical support for national strategies on ecological civilization and comprehensive green transformation.