Jianguo Liu

Michigan State University | MSU · Center for Systems Integration and Sustainability

Global sustainability challenges, from maintaining biodiversity to providing clean air and water, are closely interconnected yet often separately studied and managed. Systems integration—holistic approaches to integrating various components of coupled human and natural systems—is critical to understand socioeconomic and environmental interconnectio...

Human population size and growth rate are often considered important drivers of biodiversity loss, whereas household dynamics are usually neglected. Aggregate demographic statistics may mask substantial changes in the size and number of households, and their effects on biodiversity. Household dynamics influence per capita consumption and thus biodi...

Integrated studies of coupled human and natural systems reveal new and complex patterns and processes not evident when studied by social or natural scientists separately. Synthesis of six case studies from around the world shows that couplings between human and natural systems vary across space, time, and organizational units. They also exhibit non...

Interactions between distant places are increasingly widespread and influential, often leading to unexpected outcomes with profound implications for sustainability. Numerous sustainability studies have been conducted within a particular place with little attention to the impacts of distant interactions on sustainability in multiple places. Although...

The transboundary impacts of regional war on global food trade remain underexplored, particularly regarding disruptions to production and trade networks. Here we address this gap by developing a rapid assessment framework that integrates remote sensing, policy monitoring, and network analysis to evaluate the effects of the Russia-Ukraine war on glo...

Cities and companies have great potential to reduce pressures on Earth system boundaries. Science-based target setting has emerged as a powerful tool to help achieve the potential, but its uptake has been limited. Moreover, cities and companies usually develop their targets separately, even though many are co-located. Focusing on the top 200 cities...

In the metacoupling Anthropocene, tourism-based culture ecosystem services flows (CESF) can establish non-material bridges from the natural to the human system, even across vast geographic distances. However, there remains a knowledge gap regarding investigation of nature-related tourist travel patterns at geographic flow scales. To address this ga...

Human economic activities drive the production and consumption of goods and services, contribute to the achievement of the United Nations Sustainable Development Goals (SDGs). However, the extent of economic growth’s influence on the SDGs remains unclear. To fill this knowledge gap, here, we quantified the environmental effects of economic activiti...

Protected areas are the cornerstones of conservation efforts to mitigate the anthropogenic pressures driving biodiversity loss. Nations aim to protect 30% of Earth’s land and water by 2030, yet the effectiveness of protected areas remains unclear. Here we analyze the performance of over 160,000 protected areas in resisting habitat loss at different...

As the world’s second most consumed resource, sand is being depleted at an alarming rate. China accounted for nearly half of the world’s sand consumption in 2012. Here we present a material flow analysis of sand from 1995 to 2020 that shows China’s overall sand supply surged by approximately 400% over the study period, yet the proportion of natural...

Sustainable development depends on the integration of the economy, society, and environment. Yet, escalating environmental challenges pose threats to both society and the economy. Despite progress in addressing environmental issues to promote sustainability, knowledge gaps in scientific research, technological advancement, engineering practice, and...

Numerous Payments for Ecosystem Services (PES) programs have been implemented simultaneously around the world but their outcomes in the literature are not consistent and their interactive effects remain understudied. The Natural Forest Conservation Program (NFCP) and Grain to Green Program (GTGP) are two largest PES programs in the world, and many...

Understanding species distributions is a global priority for mitigating environmental pressures from human activities. Ample studies have identified key environmental (climate and habitat) predictors and the spatial scales at which they influence species distributions. However, regarding human influence, such understandings are largely lacking. Her...

We assessed agricultural practices in China to identify workable solutions for sustainably feeding the Chinese population. We calculated the environmental costs of producing domestic rice, wheat, corn, soybeans, and imported soybeans. The environmental costs were enormous, and the food self-sufficiency and sufficiency (im-ported soybean included) r...

Protected areas are a key component of global conservation, and the world is aiming to increase protected areas to cover 30% of land and water through the 30 9 30 Initiative under the Post-2020 Global Biodiversity Framework. However, factors affecting their success or failure in regard to promoting mammal population recovery are not well studied, p...

Amid a global infrastructure boom, there is increasing recognition of the ecological impacts of the extraction and consumption of construction minerals, mainly processed as concrete, including significant and expanding threats to global biodiversity. We investigated how high‐level national and international biodiversity conservation policies addres...

Accelerating efforts for the Sustainable Development Goals requires understanding their synergies and trade-offs at the national and sub-national levels, which will help identify the key hurdles and opportunities to prioritize them in an indivisible manner for a country. Here, we present the importance of the 17 goals through synergy and trade-off...

The Russia–Ukraine War is impacting global food systems, which may trigger global cropland expansion and consequently lead to biodiversity loss far from war zones. To quantify such impacts on biodiversity, we simulated the global cropland expansion provoked by the reshaping of international virtual cropland flows under different war scenarios and c...

The effects of various strategies aimed at simultaneously promoting environmental conservation and human development are closely related to sustainable development regionally and globally. However, although the effects of many such strategies have been evaluated by ecologists and sociologists separately, their ability to simultaneously meet these t...

Domestic attempts to advance the Sustainable Development Goals (SDGs) in a country can have synergistic and/or trade-off effects on the advancement of SDGs in other countries. Transboundary SDG interactions can be delivered through various transmission channels (e.g., trade, river flow, ocean currents, and air flow). This study quantified the trans...

Operating within safe and just Earth system boundaries requires mobilizing key actors across scale to set targets and take actions accordingly. Robust, transparent and fair cross-scale translation methods are essential to help navigate through the multiple steps of scientifc and normative judgements in translation, with clear awareness of associate...

The world is becoming more interconnected than ever before through the exchange of materials, cultures, people and knowledge. A crisis in any country or region will spread its effects cascading through time lag effects and the spatial heterogeneity of resilience. The multiple crises currently facing the world will threaten globalization and undermi...

Analyses of animal social networks have traditionally been conducted on species that exhibit social behaviors such as group living, whereas relatively less work has been done on species that are thought of as solitary, are cryptic, and that communicate through scent-marking cues. We employed noninvasive fecal genetic sampling, conducted from March...

A significant number and range of challenges besetting sustainability can be traced to the actions and interactions of multiple autonomous agents (people mostly) and the entities they create (e.g., institutions, policies, social network) in the corresponding social-environmental systems (SES). To address these challenges, we need to understand deci...

The world has become increasingly metacoupled through flows of materials, energy, people, capital, and information within and across systems. Transboundary flows, connecting adjacent and distant systems, are deemed the most critical indicators for measuring the intensity of interactions among coupled human-natural systems. To advance metacoupling f...

Unraveling the complexity of the 17 interacting sustainable development goals (SDGs) is crucial for their achievement. Empirically revealing the dimensions of the SDGs helps generalize the dominant features of SDGs and better understand their drivers. Here, using a database of 166 countries’ progress toward achieving each individual SDG, we found t...

The consequences of relying on solid fuels are disproportionately borne by minorities, the marginalized, and rural communities. However, the social disparities in transitioning from polluting energy to clean energy are not well understood. We track changes in the main energy source used for cooking among Chinese households between 2010 and 2018. We...

Climate change mitigation and biodiversity conservation are two major environmental actions that need to be effectively performed this century, alongside ensuring food supply for a growing global human population. These three issues are highly interlinked through land management systems. Thus, major global food production regions located in biodive...

Agricultural trade and climate change have altered land cover and land use worldwide. For example, the recent growth of international soybean demand has been associated with 1.3 Mha primary Amazon forest loss and up to 13-fold increase in double-cropping areas in Brazil. Many studies have tried to understand which and how global and local drivers a...

Amid a global infrastructure boom, there is increasing recognition of the ecological impacts of the extraction and consumption of construction minerals, mainly as concrete. Recent research highlights the significant and expanding threat these minerals pose to global biodiversity. To what extent is this pressure acknowledged in biodiversity conserva...

Over the last few years, understanding of the effects of increasingly interconnected global flows of agricultural commodities on coupled human and natural systems has significantly improved. However, many important factors in environmental change that are influenced by these commodity flows are still not well understood. Here, we present an empiric...

Recent climate change has caused declines in ice coverage which have lengthened the open water season in the Arctic and increased access to resources and shipping routes. These changes have resulted in more vessel activity in seasonally ice-covered regions. While traffic is increasing in the ice-free season, the amount of vessel activity in the mar...

Fisheries are coupled human and natural systems across space and time, involving movements of fish, money, and information in a globalized world. However, these social-ecological interactions over local to global scales are largely absent from the fisheries literature, as fisheries research to date has often been discipline-and location-specific. W...

The world has entered the United Nations Decade on Ecosystem Restoration (2021–2030), yet many regions of the world still face environmental degradation. In this context a question arises: under what conditions may a given region shift from a trajectory of environmental degradation to environmental recovery? Answering this question constitutes an i...

Rescuing Sustainable Development Goals (SDGs) from failing requires understanding their interactions networks, i.e., synergies and trade-offs, at national and especially sub-national levels, where SDGs were delivered. This understanding will help itendifying the key hurdles and opportunities to prioritize the 17 SDGs in a indivisible manner for a c...

Global agricultural trade creates multiple telecoupled flows of nitrogen (N) and phosphorus (P). The flows of physical and virtual nutrients along with trade have discrepant effects on natural resources in different countries. However, existing literature has not quantified or analyzed such effects yet. Here we quantified the physical and virtual N...

The global interest in moving towards a sustainable future has grown exponentially at all levels. The United Nations' Sustainable Development Goals (SDGs), adopted by world leaders in 2015, provide an integrated framework to track progress toward sustainability (UN, 2019). Textual data, such as public statements posted on websites, organization rep...

Private lands are important for conservation worldwide, but knowledge about their effectiveness is still insufficient. To help fill this important knowledge gap, we analyzed the impacts of a national policy for conservation on private lands in Brazil, a global biodiversity hotspot with high potential for nature-based climate solutions. Through the...

To meet the challenge of biodiversity loss and reach the targets of the proposed Post-2020 Global Biodiversity Framework, the Chinese government updated the list of national key protected wildlife in 2021 and has been continually expanding the protected areas (PAs). However, the status of protected wildlife in PAs remains unclear. In this study, we...

Sustainability science seeks to understand human-nature interactions behind sustainability challenges, but has largely been place-based. Traditional sustainability efforts often solved problems in one place at the cost of other places, compromising global sustainability. The metacoupling framework offers a conceptual foundation and a holistic appro...

Numerous narrow marine passages around the world serve as essential gateways for the transportation of goods, the movement of people, and the migration of fish and wildlife. These global gateways facilitate human-nature interactions across distant regions. The socioeconomic and environmental interactions among distant coupled human and natural syst...

Cities are the engines for implementing the Sustainable Development Goals (SDGs), which provide a blueprint for achieving global sustainability. However, knowledge gaps exist in quantitatively assessing progress towards SDGs for different-sized cities. There is a shortage of relevant statistical data for many cities, especially small cities, in dev...

The United Nations (UN) has adopted the 17 Sustainable Development Goals (SDGs), aiming to provide human welfare and conserve the planet, now and into the future. Two of the SDGs directly address biodiversity conservation and sustainable development – SDG 14 (life below water) and SDG 15 (life on land). Although the UN has issued annual reports on...

The growing number, size, and frequency of coastal hypoxia increasingly threaten marine ecosystem health and essential ecosystem services for human well-being. It is therefore urgent to use continuous and consistent observation and develop advanced tools to characterize and track the spatial and temporal change of coastal hypoxia. Satellite imagery...

Cities and companies have great potential to reduce pressures on Earth system boundaries. Science-based target setting has emerged as a powerful vehicle, but its uptake is still limited. Moreover, cities and companies develop their targets separately even though many large cities and companies colocate. Focusing on the top emitting 200 cities and 5...

To feed the world population while mitigating pressing nitrogen (N) pollution problems, tremendous efforts have been devoted to developing and implementing N‐efficient technologies in crop or livestock production, but limited progress has been made. The N management improvement on a farm does not necessarily translate to N pollution reduction on a...

During the COVID-19 pandemic, tourism slowed down as the world went into lockdown. This pause in tourism provides a unique opportunity to analyze the environmental and socioeconomic effects of tourism by comparing tourism participation levels before, during, and after the pandemic restrictions. We examined tourism in Iceland, an island nation in th...

Macrosystem‐scale research is supported by many ecological networks of people, infrastructure, and data. However, no network is sufficient to address all macrosystems ecology research questions, and there is much to be gained by conducting research and sharing resources across multiple networks. Unfortunately, conducting macrosystem research across...

Complex sustainability issues in the Anthropocene, with rapid globalization and global environmental changes, are increasingly interlinked between not only nearby systems, but also distant systems. Tobler's first law of geography (TFL) states “near things are more related than distant things.” Evidence suggests that TFL is not infallible for sustai...

Landscape products link to low-input practices and traditional ecological knowledge, and have multiple functions supporting human well-being and sustainability. Here we explore seven landscape products worldwide to identify these multiple functions in the context of food commodification and landscape sustainability. We show that a landscape product...

As the world grows more interconnected through the flows of people, goods, and information, many challenges are becoming more difficult to address since human needs are increasingly being met through global supply chains. Global shocks (e.g., war, economic recession, pandemic) can severely disrupt these interconnections and generate cascading conse...

In this paper, we present a spatially explicit dataset of monthly shipping intensity in the Pacific Arctic region from January 1, 2015 to December 31, 2020. We calculated shipping intensity based on Automatic Identification System (AIS) data, a type of GPS transmitter required by the International Maritime Organization on all ships over 300 gross t...

The transformational potential of the United Nations’ 2030 Agenda for Sustainable Development Goals (SDGs) lies in effective efforts to reconcile the conflicts and maximize the synergies among the interrelated SDGs. Previous research on the interrelationships among SDGs often focused on depicting the degree to which different goals reinforce or ham...

The COVID-19 pandemic has posed severe threats to global sustainable development. However, a comprehensive quantitative assessment of the impacts of COVID-19 on Sustainable Development Goals (SDGs) is still lacking. This research quantified the post-COVID-19 SDG progress from 2020 to 2024 using projected GDP growth and population and machine learni...

Achieving the 17 United Nations sustainable development goals (SDGs) in China largely depends on the transition of cities towards sustainable development. However, significant knowledge gaps exist in evaluating the SDG index at the city scale and in understanding how to simulate pathways to achieve the 17 SDGs for Chinese cities by 2030. This study...