The big picture: using wildflower strips for pest control
They may be beautiful, but these strips prove pretty deadly for every farmer's mortal enemy: aphids
News
Human activity is choking Oman’s fragile desert rivers
Wadis – lifelines for biodiversity and water in some of the world’s driest landscapes – are being dangerously constricted
23 September, 2025
Ephemeral desert rivers known as wadis – lifelines for biodiversity and water in some of the world’s driest landscapes – are being dangerously constricted by human activity, new research has found.
A study of Wadi Al-Khoud, a major watercourse in northern Oman, led by Sultan Qaboos University with Rothamsted’s Ahmed Al-Mayahi as lead author, shows that agricultural expansion and the dumping of imported soils mixed with construction debris are reshaping the river’s natural dynamics. The researchers warn the practice is narrowing channels, altering soil chemistry and sediment distribution, and accelerating erosion during flash floods.
Over a ten-year period between 2010 and 2020, the wadi’s average width shrank by 73 metres – equivalent to nearly 96,000 cubic metres of material being dumped into the channel. This narrowing creates a “bottleneck effect” that increases floodwater velocity, scouring out more sediment and spreading contaminants downstream.
Wadis should be treated as “natural hydraulic veins” and need legal protections to safeguard them
Laboratory analysis of 48 soil samples revealed striking changes in composition where alien soils had been deposited. Levels of sodium, nitrate and potassium rose by 249%, 33% and 104% respectively compared with control sites. The altered soils also contained unusually high proportions of fine silt, disrupting natural texture patterns.
The study notes that small dune-like mounds, known as nabkhas, are forming in response to the disturbances. Although their formation may be linked to human activities upstream of the Wadi, their presence provides significant ecological benefits. Studies have shown that plants growing on nabkhas can enhance water infiltration into the soil, stabilize surfaces against erosion, enrich organic matter, and support other processes that strengthen the sustainability of oasis ecosystems.
The authors say wadis should be treated as “natural hydraulic veins” and argue that Oman needs legal protections similar to urban landscaping regulations to safeguard them. Without intervention, they warn, the degradation of wadis threatens to undermine ecosystems and water security across the country’s rapidly urbanising drylands.
Image: Shutterstock
Publication
ABOUT ROTHAMSTED RESEARCH
Rothamsted Research is the longest-running agricultural research institute in the world. We work from gene to field with a proud history of ground-breaking
discoveries in areas as diverse as crop management, statistical interpretation and soil health. Our founders, in 1843, were the pioneers of modern
agriculture, and we are known for our imaginative science and our collaborative approach to developing innovative farm practice.
Through independent research, we make significant contributions to improving agri-food systems in the UK and internationally, with
economic impact estimated to exceed £3 bn in annual contribution to the UK economy. Our strength lies in our systems approach, which combines strategic research,
interdisciplinary teams and multiple partnerships.
Rothamsted is home to three unique National Bioscience Research Infrastructures which are open to researchers from all over the world:
The Long-Term Experiments,
Rothamsted Insect Survey and the
North Wyke Farm Platform.
We are strategically funded by the Biotechnology and Biological Sciences Research Council (BBSRC), with additional support from other national and
international funding streams, and from industry. We are also supported by the Lawes Agricultural Trust (LAT).
ABOUT BBSRC
The Biotechnology and Biological Sciences Research Council is part of UK Research and Innovation, a non-departmental public body funded by a grant-in-aid
from the UK government.
BBSRC invests to push back the frontiers of biology and deliver a healthy, prosperous and sustainable future. Through our investments, we build and support a vibrant,
dynamic and inclusive community which delivers ground-breaking discoveries and develops bio-based solutions that contribute to tackling global challenges,
such as sustainable food production, climate change, and healthy ageing.
As part of UK Research and Innovation (UKRI), we not only play a pivotal role in fostering connections that enable the UK’s world-class research and innovation system
to flourish – we also have a responsibility to enable the creation of a research culture that is diverse, resilient, and engaged.
BBSRC proudly forges interdisciplinary collaborations where excellent bioscience has a fundamental role. We pioneer approaches that enhance the equality, diversity,
and inclusion of talent by investing in people, infrastructure, technologies, and partnerships on a global scale.
ABOUT LAT
The Lawes Agricultural Trust, established in 1889 by Sir John Bennet Lawes, supports Rothamsted Research’s national and international agricultural science through the provision of land, facilities and funding. LAT, a charitable trust, owns the estates at Harpenden and Broom's Barn, including many of the buildings used by Rothamsted Research. LAT provides an annual research grant to the Director, accommodation for nearly 200 people, and support for fellowships for young scientists from developing countries. LAT also makes capital grants to help modernise facilities at Rothamsted, or invests in new buildings.