Carbon Dioxide Fertilisation

In the broad debate on climate change, the Australian horticulture industry is a small contributor of carbon dioxide emissions, representing just 1% of national agriculture emissions (National Greenhouse Gas Inventory 2007). However, while fertilisers are seen as the only source of emissions from horticulture in the national inventory, there are other direct and indirect emissions from horticulture, such as fuel and electricity. While net CO2 emissions are small, existing and future climate change policies place little importance on horticulture and particularly the protected cropping industry, which is a consumer of carbon dioxide to improve crop quality and yields.

Our story on Sustainable energy and CO2 options in this issue highlights that existing legislation and policy supports soil carbon sequestration and clean coal technologies, but has little or no applicability to horticultural emissions, such as the reliance on gas for CO2 enrichment, sometimes referred to as ‘CO2 fertilisation’. Although this article primarily focuses on CO2 options for greenhouse growers that reduce their carbon footprint, it also draws attention to the inaction to ensure that future legislation mitigates CO2 fertilisation.

At this point, it’s worth highlighting the recent report, Carbon Dioxide: The Good News, produced by the The Global Warming Policy Foundation. In this document, former IPCC delegate, Dr Indur Goklany, reports that carbon dioxide fertilisation, and emissions from fossil fuels, have had a hugely beneficial effect on global crops, increasing yields by at least 10-15%, which has helped reduce hunger and advanced human well-being.

Another document worth reading is the recently published Climate change and the Australian horticulture industry brochure, produced by Horticulture Australia Limited and the Climate Change Research Strategy for Primary Industries, which outlines carbon dioxide abatement strategies for the horticulture industry.

The coming legalisation of medical cannabis in Australia has been a long time coming. Our story on medical cannabis in this issue briefly charts the history and taxonomy of cannabis, and current research. The author is eminently qualified as a scientist and researcher to identify the challenges ahead to grow medical-grade cannabis, having visited major cannabis research facilities in Europe and North America. From his investigations, it’s clear that much work is needed to develop horticulture growing practices to produce consistent medical-grade cannabis products. There are still many questions that remain unanswered in relation to the production of medical cannabis.

Once legalised in Australia, it may take many more months if not years before we see the development of high-grade medical cannabis products to treat a range of maladies, even with the help of overseas pharmaceutical companies. The development of a Federal regulatory scheme and the coming legislation to produce medical cannabis is only the beginning of what will become a new commodity in Australian horticulture, as well as create a new branch in medical research.

As we start the New Year, there are good indicators that the Australian economy has bottomed out and trending upwards. Retail sales and personal income are up, unemployment is trending downwards, and the US economy, which has a global impact, is slowly recovering. Additionally, elements of Free Trade Agreements with China, Japan and South Korea have kicked in, which will flow through the economy in the months ahead. That can only be good news for the horticulture industry. I wish all our readers and advertisers a happy and prosperous 2016.  Ω

Steven Carruthers

PH&G January 2016 / Issue 163