Successful protection of biodiversity requires adequate pesticide and nutrient pollution indicators

Published on
September 18, 2023

One million animal and plant species are under threat of extinction worldwide. One of the main causes of the loss of biodiversity is the pollution of nature by nutrients and chemical pesticides. Agricultural economist Niklas Möhring: “The member states of the United Nations have set global targets to halt the loss of biodiversity. To reduce pollution and protect biodiversity, researchers and policy makers need adequate indicators with which to measure progress. In our report, we highlight some of them.” The article ‘Successful implementation of global targets to reduce nutrient and pesticide pollution requires suitable indicators’ was published in Nature Ecology & Evolution.”

Life on earth is not possible without biodiversity. The interaction between plant systems, animal systems and ecosystems forms the basis for a healthy living environment, sustainable food production and mitigating climate change. This means nature restoration is crucial. For this reason, the Netherlands has committed to an agreement adopted at the UN biodiversity summit in late 2022, the Global Biodiversity Framework (GBF). ”The agreement’s goals are ambitious,” Niklas Möhring explains. “By 2030, the nitrogen and phosphorous surplus lost to the environment and the overall pesticide risk should be halved. To achieve this, we need good indicators that policy makers, researchers and nature organisations can use to guide their actions to reduce pollution and protect biodiversity.”

Sources of nutrient pollution

According to Möhring, the proposed indicators for nutrients in the GBF text are inadequate, and there is no agreement yet on the methodology for pesticides. So he started working with colleagues from universities around the world, including Wageningen University & Research. In their report, they highlight a number of relevant indicators that could strengthen the GBF monitoring framework. “For nutrient pollution, the current indicator is the Index of Coastal Eutrophication Potential. This is a well-established indicator, but it has a limited focus on the ratios of nitrogen loads, phosphorous loads and silicon loads in rivers. This makes it less relevant to the broader issue of the effects of nitrogen and phosphorus pollution on biodiversity and ecosystem services. Moreover, it indicates effects rather than the sources of nutrient pollution. There is good evidence that nutrient source indicators are much more effective in informing and implementing policies to reduce pollution.”

Pesticide pollution

The researchers also provide advice on indicators of pesticide pollution, for which there is no agreed methodology yet. “It is important to think about the risks pesticides pose to biodiversity. We should not look at the applied force of pesticides, since certain plant species and animal species, such as bees, are at high risk from highly toxic pesticides, even if people use them in small quantities.”

Wastewater and fossil fuel combustion

The researchers call for a joint approach to pesticide and nutrient pollution, looking at all sources. In addition to agriculture, these include wastewater and fossil fuel combustion for nutrient pollution. "It is known that losses in the environment affect biodiversity, regardless of the source,” Möhring explains. “It is also important that we adapt global targets to national and geographical contexts. Look at China and the Netherlands, countries with large nitrogen surpluses from agriculture. These countries have ample opportunities to reduce these losses with country-specific approaches. While other countries, such as ones in Africa, need to almost triple nitrogen inputs to improve soil fertility. So, how much less nitrogen can be released into the environment should be tailored to the specific region.”

According to the researchers, it is possible to meet reduction targets while maintaining food security. “Importantly, we don’t have to stop using pest control or providing nutrients to plants. However, we need to find and implement changes in crop management and the use of new technologies, combined with changes in diets, reducing food waste and recycling nutrients. We should also look at other approaches, such as new pesticide-free production systems. This transformation will succeed if we build bridges between researchers from different disciplines, policy makers, farmers and other stakeholders in the food value chain.”