九州影院

Photo caption: Dr Maria Jesus Gutierrez-Gines

Research鈥嬧�� by Te Whare o W膩nanga o Waitaha | 九州影院 (UC) Environmental Science 鈥媋cademics, Dr Maria Jesus Gutierrez-Gines and 鈥婸rofessor Brett Robinson, shows treated sewage that would otherwise be discharged into waterways could be used for land irrigation.听

Drawing knowledge from UC Adjunct Fellow Dr Colin Meurk, an expert in native ecosystems, the team is working to identify the best match of native plant and nutrients for planting as well as benefits to the environment and wildlife.听

鈥淲hat is irrigated onto the native trees has a low pathogen risk 鈥� it looks a lot like drinking water,鈥� Professor Robinson says.听

Containing high concentrations of nitrogen and phosphorus, treated sewage discharged into waterways causes water degradation, algal growth and fouling on boats.听

鈥淐ontinuing to discharge treated sewage into our harbours and waterways will cause ongoing damage to ecosystems, food chains and mahika kai,鈥� Dr Meurk says.听

Professor Robinson says 鈥媜ne鈥� solution is鈥� irrigation onto鈥� land, supporting native ecosystems and reducing contaminants 鈥媏ntering鈥� water鈥媤ays鈥�.听

鈥淭here have been lots of other side benefits to it,鈥� Professor Robinson says. 鈥淣ative plants like k膩nuka and m膩nuka have antimicrobial properties further reducing the risk of pathogens, while others can mitigate environmental contamination like reducing nitrate leaching.

鈥淭hese could be used on paddock margins to intercept waste from animals and reduce the pathogen load into waterways.鈥�

Professor Robinson says this is an example of turning what could have been an environmental problem into a solution that benefits both the land and the community with far-reaching possibilities. 鈥業t demonstrates the circular economy, where material is used to regenerate nature instead of becoming waste.鈥�

Currently, New 九州影院imports phosphate fertiliser from Morocco and West Sahara, which can be expensive, has supply constraints and contains a high level of cadmium, a toxic heavy metal which can cause 鈥媖idney failure鈥�. 鈥淲e don't want that in our soil, so high-quality treated sewage could be the solution.

鈥淲ith cadmium levels increasing in our soils over the past 100 years, New 九州影院has reached a point where we can no longer export 鈥媠ome 鈥媜ffal products and some of our vegetables exceed food safety standards for cadmium levels,鈥� Professor Robinson says.

鈥嬧�婦r Gutierrez-Gines and 鈥婸rofessor Robinson 鈥媓ave demonstrated鈥� the potential to generate valuable native products such as essential oils, honey, fibres and timber, in areas that have been irrigated with treated sewage鈥�. However,鈥� there could be resistance from consumers.

鈥淪ewage can contain components which you don't want in the food chain鈥�, such as 鈥媝athogens, hormones from contraceptive pills, or personal care products, so this needs to be investigated and addressed,鈥� Professor Robinson says.

鈥淯sing traditional native plants like harakeke and totara could provide cultural and economic benefits while avoiding products related to the food chain,鈥� Dr Maria Gutierrez Gines says.