Sharply reduce pollution in terrestrial ecosystems

While minimizing the introduction of pollutants to terrestrial ecosystems is a critical priority, for pollutants that are already present and do not degrade, efforts are needed to remediate soils to alleviate long-term contamination. A variety of technologies — including soil washing, phytoremediation and adsorption methods — are in use or in development to address existing soil contamination from metals and PFAS that can persist in ecosystems for decades or centuries.

However, additional research is required, as many existing remediation methods for these pollutants remain costly and have varying levels of effectiveness. In developing remediation technologies, it is essential to conduct full life-cycle assessments to ensure that these inputs or processes do not lead to a net increase in environmental impacts.

Developing these and other related innovations can require financial investment in research and development (R&D), especially to test large-scale applications of technologies outside of laboratory settings. However, there is currently no publicly available information on global spending on research and development on technologies and interventions to remediate pollution.

Safely treating wastewater flows is essential for both human health and minimizing pollution entering terrestrial ecosystems, such as wetlands, marshes, bogs and fens. Advanced wastewater treatment technologies have historically reduced excess nitrogen and phosphorus entering inland and coastal wetlands. However, much of the existing infrastructure across the globe is outdated, in disrepair, or unable to adequately cover or process wastewater flows. This issue is especially pronounced in low- and middle-income countries, where many regions lack waste reduction and treatment technologies altogether or cannot afford the advanced technologies needed.

The share of wastewater flows that is safely treated is indicative of the availability and use of wastewater treatment technologies. Although data is limited, only 56% of tracked household wastewater in 2024 was safely treated before being discharged. While data on industrial wastewater treatment is even sparser, only 27% of tracked industrial wastewater flows in 2022 — available from 22 countries representing 8% of the global population — were safely treated before discharge.

In addition to improving wastewater treatment, stormwater runoff management is also critical to minimizing pollution from runoff into wetland ecosystems.

Nitrogen is essential for crop growth, and nitrogen fertilizers have been one of the primary drivers of increased crop yields achieved over the past century. However, overapplication and excessive nitrogen losses from crops lead to agricultural runoff, air pollution and soil acidification that can spread to wetlands and other terrestrial ecosystems.

Nitrogen use efficiency (NUE) measures the ratio of nitrogen absorbed by crops and nitrogen fertilizer applied. A high NUE indicates that crops are efficiently using the applied nitrogen, while a low NUE suggests that much of the nitrogen is not being absorbed by the crops. Research suggests optimal NUE is around 0.70, even up to 0.75 in highly efficient farming systems. Higher NUE can be achieved with practices such as efficient irrigation, balanced micronutrient application, improved planting methods and precise timing of nitrogen applications to align with crop needs.

Tracking NUE over time shows the availability and application of technologies and practices to reduce excess nitrogen losses. Aggregate data on NUE is only available for a large subset of OECD member countries, in which the median NUE increased by 11% between 2000 and 2020, from 0.55 to 0.61. However, progress in recent years has stagnated.

Addressing pollution requires a coherent and targeted strategy across government, society and the private sector. However, pollution often falls solely under the jurisdiction of environment-related ministries or agencies, which in most cases, are “relatively weak” compared to other ministries.

Having a coherent national biodiversity strategies and action plan (NBSAP) that includes specific targets for reducing pollution provides a roadmap for effective action. An NBSAP details how a country intends to reduce pollution, the steps required to meet the country’s goals and a time frame for action. Producing an NBSAP also provides a means of centralizing knowledge, gaining stakeholder buy-in and mobilizing funding for policy implementation and monitoring.

As of September 2026, 87% of the 169 countries that had NBSAPs with at least one national target included at least one target on pollution in their plans. In addition to the presence of pollution targets, it is important to ensure that these targets are comprehensive in the types of pollutants addressed and sufficiently stringent to protect human health and biodiversity, although such information is not currently available.

To mitigate pollution from the spread of pesticides applied to agricultural fields into nearby terrestrial ecosystems through surface water runoff, groundwater contamination (through plant roots), airborne drift, and deposition, stronger water quality standards and pesticide use regulations are needed. These regulations should also have a wider coverage and integrate the latest science on pesticide use and effects on biodiversity. Other policy mechanisms, such as taxes on pesticide use and incentives for the adoption of integrated pest management practices, may also reduce pesticide use.

Global time series data on the coverage area and strength of different policy mechanisms to disincentivize or regulate the application of pesticides is unavailable. Instead, the average number of Highly Hazardous Pesticides (HHPs) banned within a country can serve as a proxy of the pesticide regulatory landscape, as pesticide bans have been associated with reduced pesticide pollution risk in Europe. On average, between 2015 and 2024 (the most recent year with available data), the number of HHPs banned within a country from 19 to 51. Notably, 71 new countries were added to the dataset in 2022, which means the average is influenced by those new countries.

Though recycling can help minimize the negative effects of plastic pollution, total plastic accumulation in the environment continues to increase. Reducing plastic pollution requires a multipronged approach and strong policies to regulate the production of plastics from virgin feedstocks, encourage reusable packaging design, reduce the consumption of plastics (especially single-use products) and improve plastic recycling and waste management strategies. For example, Extended Producer Responsibility is a policy tool that, when appropriately implemented, can motivate companies to redesign products to increase reuse and recycling by making producers legally and financially responsible for mitigating the environmental impacts of their products and packaging.

Based on data from the Global Plastics Laws database, as of 2025, 77% of the world’s population lived in countries with a law, policy or regulation that mandated, incentivized or otherwise facilitated practices that minimize pollution in plastic production, consumption and waste management. Plastic-related policies most commonly pertain to reducing plastic use (68% of the world’s population covered by such policies), followed by those focused on recycling and waste management (58%), maritime sources (40%), extended producer responsibility (30%), design and reuse (26%) and microplastics (21%). Policies regulating the production and manufacturing of plastics were the least common (8% of the world’s population covered by such policies).

While preventing areas from being artificially lit is the most effective option to reduce light pollution and its negative effects on biodiversity, the expansion of urban development in many parts of the world makes this an often infeasible aim. A variety of policies, including regulations or ordinances, can be used to minimize light pollution, from the international to local level. That said, most existing policies are non-legislative strategies or nonbinding recommendations, which have limited enforceability.

In the absence of data on the share of global land covered by a light pollution regulation, the area covered by Dark Sky Places offers a proxy to identify land with responsible lighting policies and public education efforts. A variety of publicly and privately owned locations can be certified as Dark Sky Places following different criteria, including remote protected areas as well as towns, cities and parks with responsible lighting policies and public education efforts. Not only do Dark Sky Places help preserve areas that are minimally impacted by light pollution, but they also can serve as models for biodiversity-friendly lighting practices that can be replicated elsewhere.

As of 2022, international Dark Sky Places covered 16 million hectares, an area roughly the size of England and Wales combined.

In addition to government policies and manufacturer changes to reduce plastic production, consumer norms and expectations, such as the desire for single-use items, also influence plastic consumption. Similarly, while policies can facilitate easier recycling, consumer knowledge, skills and practices contribute to low recycling rates.

Increasing consumer awareness of plastic overconsumption may help shift consumer behavior and social norms toward reusable and lower-plastic options. It can also lead to increased pressure on corporations to develop plastic alternatives, and on policymakers and regulatory agencies to introduce measures to ban plastic products. For example, following a 2012 awareness campaign, consumer attitudes toward plastic microbeads in beauty products shifted significantly, and grassroots activism and lobbying efforts were successful in prompting the European Union, South Korea and the United States to ban the use of plastic microbeads in certain personal care products.

This indicator aims to gauge people’s intentions and behaviors by measuring the share of people who are aware of plastic overconsumption and willing to adopt low-footprint consumption options. This indicator has been included to highlight the importance of changes to social norms and behavior; however, the effectiveness of educational campaigns in achieving this is mixed. Public education campaigns may be beneficial but insufficient on their own to facilitate shifts in plastic consumption.

Though there is a lack of global data exploring awareness and behaviors pertaining to plastic overconsumption specifically, survey results from select countries show us the share of people who seek out products that are biodegradable, eco-friendly or come with less packaging. About 82% of people surveyed in 28 countries in 2022 said that they want to buy products that use as little plastic packaging as possible. Beyond changes in packaging, one survey in 2021 found that about half of consumers said they were buying more biodegradable or eco-friendly products, with millennials (people born between the mid 1980s and late 1990s) being the most inclined (up to 59%) compared to other generations.