Friday, June 15, 2018

Citrus Canker Update for NT - 15 June 2018

At a press conference this morning a new location has been announced where citrus canker has been detected - the Marrakai area SE of Darwin.

The Press release is here -
As noted, once again as for all others, it is present on nursery stock supplied from a single nursery in the Darwin area.

While there seems to be no detection of the disease on commercial citrus producers so far, the question that is absolutely pertinent has not been openly explored.........what is the origin of the infection in the nursery?  Everyone seems to be skirting around this issue, or at least can the identification of possible sources be explained, and also how long it may have been present.

So far the traceback is extending to 12 months before first confirmation, so presumably, it may have been around in the nursery for that period, or up to that period.

While getting on with methodical work locating the movement of material from the nursery continues [ and there seems to be evidence quite a lot have gone interstate], the method of infection is not openly discussed, or argued.

Maybe it was windborne spores .......technically possible, if insects can move into the region from airborne travel in monsoonal weather [ blue tongue insect vectors for example].

Thursday, May 24, 2018

Safe Spraying - What is Delta T?

Delta T is used by the agricultural industry. It is an important indicator for acceptable spraying conditions. It is indicative of evaporation rate and droplet lifetime. Delta T is calculated by subtracting the wet bulb temperature from the dry bulb temperature. When applying pesticides, Delta T should ideally be between 2 and 8, and not greater than 10. Select the right Delta T to determine the best weather conditions for spraying(PDF 593 Kb).

The diagram below relates air temperature and relative humidity to values of Delta T.

Graph of Delta T

This detail comes from the Australian Bureau of Meteorology, and Delta T values are generally available on many site pages, especially where regular automatic data collection is occurring.

Considered a very useful tool if you are spraying agrochemicals, with a guide being that if in the range of 3-7, it is okay to be spraying [ a 2-8 range is about the safe limit as above hence a small safety margin for security].

You can check for previous conditions as a check for likely conditions the next day in many areas where weather is reasonably stable.

In the Top End, evening and early morning are generally safest, with the Delta -T value within a suitable range, but......not always.

If you can, plan ahead and check just before spraying.  Warm temperatures will drive it up, but there is often a guide for many chemicals to use below 30C, sometimes a bit difficult to achieve, so less effectiveness might be expected.

It may be possible to adjust spray parameters - pressure, droplet size and spray direction for example to compensate for poor conditions if spray events are critical, but often it may be prudent to wait a little time for better conditions eg early am or evening. 

In the dry, but cooler dry season in the north, it is quite common for the Delta T to be well above 10 in the afternoon, when both above 30C is common and RH is very low [less than 30%] - obviously avoid this time for spraying!!

There are commercial services available from a number of agribusiness firms, some of which do add some additional options.  However, with the Delta T values and graph available, you can quickly check yourself too for no real cost, except your time to check.  It is simple, but a desirable check before spraying.

Friday, May 18, 2018

Biosecurity Problems for North Australia - New Issues

Two biosecurity issues have emerged recently in the Darwin area, both with potentially catastrophic outcomes for Australian agriculture if not solved.

A few weeks ago citrus canker was detected in a nursery near Darwin, and subsequently found on six properties in the near Darwin area.  Today it has been announced now also found in the Kununurra /Wyndham area of WA with the source apparently from an NT nursery.

This is potentially a  major issue for the Australian citrus industry.  Early days, but eradicating it will be a big task.  Yet, in Florida where outbreaks occur with some monotony, it is also regularly eradicated from large orchards but using a cut and burn approach.  Serious stuff requiring a serious approach.

The other is a detection of Asian honey bees in Karama, a Darwin suburb.  The swarm has been eliminated, but they are seeking any nests and these require checking for varroa mite, the main problem.  This is some distance from the Darwin port, and with ports seen as a likely point of entry, the distance away from the port is perplexing.  Will be more to come on this one too.

If detected there are larger implications for the whole Australian honey and queen bee industry [ yes, Australia exports queen bees!].

Both early days, and there is more on this web site, and the ABC Rural has had stories on both subjects recently.

See - 

A word of advice - check your citrus tree or trees for citrus canker!! 

UPDATE - 7 June 2018

More citrus canker has been discovered.........with a number of trees including one with a severe infestation, discovered in the Katherine area.

Not a good find!

Check any citrus trees on your property, and do not move fruit or vegetative materials of citrus.  Check the link above for the current current situation.

This is a very serious issue, for local citrus producers as well as the huge citrus industry interstate. 

Wednesday, May 16, 2018

WoolCool - Sustainable Insulating Packing from Waste Wool

This is a very clever idea that is sustainable and could replace expanded polystyrene which tends to be single use packaging.

Friday, 04 May, 2018 | Supplied by: WoolCool

Bigboxfood1 packaging picture
Woolcool Australia has been acknowledged at the 2018 WorldStar Packaging Awards for its innovative insulated packaging solution, made from a product that is both sustainable and effective — sheep’s wool.
The Packaging Awards were presented at the Australian Institute of Packaging National Conference, held on 2 May in Surfers Paradise. Woolcool won bronze in the Packaging that Saves Food category for the development of its packaging solution, made from sheep’s waste wool combined with a recyclable, food grade liner.
Wool is a good insulation material as it is extremely effective at absorbing moisture from the air, which creates stable temperatures through minimising humidity and condensation. Woolcool’s technology combines a complex blend of wool fibres from different breeds of sheep to provide consistent optimal insulative properties. This wool is felted into a liner and sealed within a recyclable food grade film.
The result is a packaging product that keeps cold products cold and hot products hot, with the added benefit of a protective cushion to safeguard products in transit. These thermal qualities enable the product to ‘save food’ by reducing the wastage often experienced using traditional insulated packaging in the transport and delivery of temperature-sensitive food.
Sustainable, renewable, biodegradable, compostable, recyclable and re-usable, the product has been shown to outperform synthetic packaging materials, including polystyrene. It also has the potential to open new markets for cool chain supply companies, as it is allowing frozen and chilled products to be transported much greater distances and still arrive in the same fresh condition.
Woolcool is proudly endorsed by Planet Ark, with the latter stating that the increasing use of expanded polystyrene (EPS) boxes for home grocery delivery services and pre-prepared meals is resulting in a range of negative environmental impacts.
“Latest statistics indicate that only 29.4% of EPS is currently recycled and the remainder either goes to landfill or ends up polluting our environment and waterways,” said Planet Ark Partner Relations Manager Kristie Baker.
“Woolcool offers a real alternative to traditional insulated packaging like EPS and we encourage businesses to shift their reliance from petrochemical-based products like EPS to renewable alternatives like Woolcool.”
Howarth says that since Woolcool was launched in Australia and New Zealand, an estimated 2.5 million boxes of polystyrene have been removed from the environment.
“That’s just a tiny fraction of the total number of petrochemical-based boxes used once and discarded across Australia and New Zealand every year,” she said. “Imagine the difference we could make if we eliminated polystyrene insulated boxes from our environment altogether — it’s now possible!”
Image credit: Woolcool.
Phone: 02 9665 2665

Monday, May 14, 2018

Blackfella Beef - Concept Announced

At Beef Week in Rockhampton in early May 2018, the  Queensland Senator Matt Canavan launched the Blackfella Beef concept.

Quite a few news articles on line and worth a read.

The idea of Blackfella Beef was developed by the Wangan Jagalingou and Western Kangoulu Indigenous groups and has garnered financial support from Meat and Livestock Australia (MLA) and the University of Southern Queensland.  The image below is of Jonathan Malone and Kelvin Dunrobin launching  Blackfella Beef at Beef Week  with Stairmaster the champion Senepol bull.
The next step is to identify how many Indigenous-owned cattle enterprises there are in Queensland that could market their beef products under the brand.
With a significant number of beef properties owned and /or operated by indigenous Australians, predominantly across north Australia, the concept has a lot of marketing potential.  There seems to be a degree of support among indigenous people in the industry, at least in Queensland so far.  Certainly there are many large cattle properties in the NT and the NW of WA that are owned and operated by local indigenous groups that could be part of such a group.  

But it has to do more than just be an indigenous brand - if it does not offer quality beef it will be wasted.  It has to offer advantage or it will be meaningless.

Quality beef includes genetics, stock handling, quality as well as seasonal issues, especially across the north, and management - on and off the property and through to customer quality and branding.  Certainly a lot to consider.

Will it be organic beef?  With organic beef a fast growing commodity, many of the northern properties could be set up to qualify for this category, but often handling through the slaughter process can be problematical to maintain authenticity.

There is a long way to go yet.

Saturday, May 12, 2018

Cold Weather and Zoysia - Colour Change

We are being advised by the BOM of a week of very cold weather that is coming next week - say 13 - 21 May 2018.

Some in the BOM are saying some of the coldest weather for many years is expected across southern and eastern areas of Australia next week.

Cold weather will turn almost all zoysia turf areas a golden tan or yellow colour.  Little can be done to avoid it.

A very common and totally normal issue in China and Korea in winter [ both have extensive naturalised zoysia grass regions] as well as in some parts of the USA where zoysia is used.  It is well known here in Australia eg parts of Melbourne in cold winters, but not necessarily every year.

So be aware - your zoysia lawn is unlikely to die, but is also likely to not be green in the cooler weather if heavily affected.

Recovery is expected in warmer weather in spring.

First plot - dormant zoysia turf in winter -fescues green behind [US photo] 

Friday, May 11, 2018

Solar Panel Disposal - Emerging Problem?

So far there has been a relatively modest need for safe disposal of solar panels - most are going onto the roof and not off the roof!

Elsewhere in the world though some areas are now discussing how this disposal of the solar panels at "end of life" can be managed effectively.

The growth in solar energy use over the past 25 years has been exponential, at times being called a "sunrush". In addition to increasing global capacity from 100 MW to over 300 GW in that time, costs in 2017 were an impressive 86% less than in 2009!
A solar array in rural area
One emerging concern, however, results from the fact that the effective life cycle of a typical solar panel is about 25 years. The glass and metal material from retired photovoltaic (PV) panels will begin to add up to millions of metric tons in the near term, and current recycling infrastructure may not be sufficient for dealing with such a large quantity of these materials.
Perhaps unsurprisingly, the process of recycling solar panels is fairly complicated, involving heat systems that burn up the adhesives as well as other methods used to separate out the crystalline silicon and the precious metals in the panels. The wide variety of materials used—from glass, aluminum, and synthetic sealing materials to metals like lead, copper, and gallium—makes it difficult to efficiently process and recycle them. Mark Robards, director of special projects for ECS Refining in the USA, says, “Nearly 75% of the material that gets separated out is glass, which is easy to recycle into new products but also has a very low resale value” (quoted on the website 
If they aren’t recycled, PV panels in many jurisdictions around the world cannot be sent to landfills since they are made with heavy metals and other toxic substances that can contaminate the surrounding soil, air, and water.  And not a lot to effectively solve the problem is occurring in Australia [maybe okay in South Australia].
Along with the current difficulties of recycling solar panels, the changing makeup of the panels themselves presents a challenge. As manufacturers continue to improve their technology, they search for more cost-effective ways to construct panels. These methods often involve using alternative components—like a material called perovskite—rather than more easily recyclable materials like silver and copper. While solar panel costs are dropping and enabling the technology to become more widespread, the need for better recycling infrastructure is growing every year as more and more panels reach the end of their life span.
Large commercial solar plant
The solar energy industry in the US may take inspiration from a recycling association in Europe called PV Cycle which has developed a process for PV module recycling that is both environmentally and economically conscious. In 2016, they achieved a 96% recycling rate, a new record for silicon-based solar panel recycling. The head of Treatment & Operations at PV Cycle, Olmina Della Monica, remarks that their success “is the result of both continuous improvement and intensive research and development along the value chain.” Here in Australia there has been so far, little recognition of the emerging and potential problem, and with solar energy development widespread across remote areas, safe disposal is looming as expensive and difficult.
In contrast to the US, Europe’s PV panel disposal management is regulated by the EU’s WEEE (Waste of Electrical and Electronic Equipment) directive. Manufacturers of solar cells must obey legal requirements and specific recycling standards, operating with the mindset that these panels will need to be recycled at the end of their life span. There is no similarly strict control in the US, but California has initiated legislation on solar panel disposal that supports the PV module industry in making end-of-life management of PV modules convenient for both consumers and the public. 
As the “sunrush” continues, legislation like this will hopefully become ubiquitous across some of the major adoptors including China, Australia and the USA.  If solutions are not explored and widely developed the disposal of these panels will be a serious and very significant waste problem.  Designing for easy separation of components and metals would be a sensible start to better disposal and recycling options.
[some material based on an article by Jessica Read in Forrester Daily News April 30 2018]

Wednesday, May 09, 2018

Planting Zoysia Seed 2018 - Australia

It is time to put away the thoughts about planting zoysia seed in Australia - at least for some months.  Possible exception might be for northern Australia, but even there, it might be prudent to wait for a while, which I shall discuss a bit more.

As I write this blog today, the BOM is predicting some seriously cool weather approaching Australia from the south and west - with the coming week [12-20 May] commencing with the weekend of 12 / 13 May expected to be very cool [more northern areas] to very cold in the south.  But.......not before time really.

However, while planting is not wise for some months now, it does allow adequate planting and preparation time, with an emphasis on absolutely minimising or eliminating weeds in the projected sowing areas.  Ideally, use the germinate - grow a little - kill technique for weeds, using herbicides with glypghosate a prime choice [ but not the only option], or even tillage.  While it may now be too cool for spring and summer growing plants to emerge, they will come with the warmer weather from August onwards.  So be prepared!

In northern areas we prefer to see areas established from mid to late August or a little later.  But it is not so much temperature issues, although it is lower although technically suitable, from now on for a while, as the effects of shorter days and cool nights impacting growth,plus with dry season weather, it is often easier to delay, to avoid excessive irrigation needs of several months that can be avoided by a delay to the start until August or about then, but before the weather becomes too hot requiring much greater irrigation requirements.  Zoysia growth certainly improves from August with warmer weather around, and longer days.

The other good news is that it is likely that adequate Compadre zoysia seed will be available in that period, based on known stock levels now.  This is in stark contrast to the past several years in Australia when seed stock levels were negligible, and with poor chances of getting more.

If considering a new zoysia lawn using seed later in 2018, plan ahead and we are happy to discuss seed supply and site planning with potential customers.

It is also worth noting to those who have a zoysia turf area of almost any type in southern Australia- you can probably expect cold nights  - and there is potential for your zoysia to turn a golden tan colour in the cold weather.  It will recover in spring........but certainly a week of very cool nights will shut growing down. 

Best contact is by email to:  .

Thursday, April 12, 2018

Gene Editing - A Comment By Bill Gates

I have made remarks here on my blog about CRISPR gene technology as well as a few posts on gene editing and its relevance to modern agriculture and science in general.  I think it is a marvellous technology tool with enormous potential for variety improvement in agriculture.

A recent post highlighted the fact that the USDA has concluded that using CRISPR gene editing is not the same as creating GMO varieties - as no transgenic change occurs.  This allows a less ardous pathway to commercial use for new products developed through this technology, as they are not GMOs.

The comment below by Bill Gates [the one from Microsoft!] might have more clout than me, but he is a strong supporter of genetic improvements across a wide field and now has close contact with eminent researchers  through heading the Bill and Melinda Gates Foundation which supports international research and development.  And he supports CRISPR work generally.

It is worth reading..........

link below:

Monday, April 09, 2018

IP Protection Includes Seeds

The US has made much of the loss of intellectual property to China in recent years.  And in agriculture this includes new varieties and the seeds of those new varieties.

A recent court case has highlighted a new variety that seems to have been on its way to China.......but was detected at the US border.

Sobering reading.


Chinese Scientist Sentenced to 10 Years in Prison for Rice-Smuggling Plot

The researcher stole genetically modified seeds and planned to give them to a crop research institute in China, the US Justice Department says.
By Ashley Yeager | April 5, 2018
FLICKR, BLOGTREPRENEURChinese scientist Weiqiang Zang was sentenced yesterday (April 4) to 121 months in federal prison for conspiring to steal genetically modified rice seeds from Ventria Bioscience while working at its Kansas-based facility. Zhang planned to give the seeds to a research institute in China, according to a statementfrom the US Justice Department.
“Weiqiang Zhang betrayed his employer by unlawfully providing its proprietary rice seeds to representatives of a Chinese crop institute,” Acting Assistant Attorney General Cronan says in the statement. The “sentence demonstrates the significant consequences awaiting those who would steal trade secrets from American companies.”
Zhang, who has a master’s degree in agriculture from Shengyang Agricultural University in China and a doctorate from Louisiana State University, worked as a rice breeder at Ventria Bioscience. The company develops rice seeds that are genetically reprogrammed to produce human serum albumin, a protein found in blood, or lactoferrin, an iron-binding protein found in human milk. The proteins are then extracted for use as therapeutics.  
According to trial evidence, Zhang stole hundreds of the company’s rice seeds and stored them at his home in Manhattan, Kansas. In the summer of 2013, visitors from a crop research institute in China came to Zhang’s home, and Zhang also took them to tour research facilities in Iowa, Missouri, and Ohio. When the visitors returned home in August 2013, US Customs and Border Protection officers found seeds, including ones belonging to Ventria, in their luggage. Last February, Zhang was convicted of one count of conspiracy to steal trade secrets, one count of conspiracy to commit interstate transportation of stolen property, and one count of interstate transportation of stolen property.
“Ventria invested years of research and tens of millions of dollars to create a new and beneficial product,” says US Attorney McAllister in statement. “It is vital that we protect such intellectual property from theft and exploitation by foreign interests.”

Friday, April 06, 2018

Organic Fertilisers - Contamination with Microplastics Common - Take Care

Users like to belive thay are being positive for the environment by using waste organics that have been converted to organic fertilisers -small pellets or even as bagged compost or by the trailer load.

Recent studies however, confirm the presence of considerable amounts of microplastics in many of the organic fertilisers used around the world.  Most work has been conducted in Europe and North America, but it is highly likely the situation will be broadly similar in Australasia.

While some effort - or even a big effort- is made to eliminate plastics in the original waste stream, it is rarely totally successful, and they get broken up in processing eventually being in the final product as microplastic pieces [ defined as <5mm font="" in="" size="">

There is a lot of discussion about microplastics in both fresh and marine waters, and land contamination is also of  concern.

We really do not understand the potential problem with land, and issues when contamnated areas are used for food production.

More below from a recent article which appeared online.
The recycling of biological waste from homes and businesses to make fertilizer, either through composting or fertilization, is a source of microplastic pollution, according to a study published today (April 4) in Science Advances. The particles were present despite efforts to sort and sieve out plastic contaminants either before or after the waste was processed, the authors note.

“The recycling of organic waste through composting or fermentation and subsequent application on agricultural land is, in principle, an environmentally sound practice to return nutrients, trace elements, and humus to the soil,” the study authors write. “However, most household and municipal biowaste is contaminated by plastic material.”

See “Plastic Pollutants Pervade Water and Land

Microplastics, which the new study defines as plastic particles smaller than 5 mm, result from the breakdown of plastics, and are pervasive both on land and in the oceans. While the extent of their environmental and health effects is not clear, studies have found they’re detrimental to the health of organisms such as earthworms and rodents, and that they make their way into human food supplies.
In the new study, researchers at the University of Bayreuth in Germany investigated fertilizer produced by a biowaste composting plant (which treats waste aerobically) and a biowaste digester (which uses an anaerobic process). There were fewer than 25 microplastic particles per kilogram in the compost from the first plant, while the freshly-digested fertilizer from the second plant had up to 146 particles per kilogram of the pollutants. By contrast, no microplastics were found in digestate from an agricultural energy crop digester, suggesting that the contamination in the products from the first two plants originated in the homes and businesses that were the source of the waste used.

Tuesday, April 03, 2018

Varieties Developed via CRISPR to be Less Regulated in USA

As CRISPR gene editing only edits the genome and does not insert foreign genetic material from other species the light hand of regulation may be considered as adequate, or does it need more regulation?

So far it seems that less is adequate, which is generally accepted by many involved in new crop and horticulture variety devlopment.

The following article is a brief, but relevant take on the subject from The Scientist online magazine. This attitude is likely to influence other countries regulatory agencies.

USDA Will Not Regulate CRISPR-Edited Crops

Restrictions will remain on transgenic plants, which contain artificially inserted genes from other species.
By Diana Kwon | April 2, 2018
The US Department of Agriculture (USDA) will not regulate plants that have been modified through genome editing, according to a statement released last week (March 28) by the agency.
In the announcement, the USDA states that it won’t oversee the use of genetically altered plants, as long as they could have also been developed through traditional breeding methods, such as cross-breeding or selecting for desirable properties. The agency adds that genome editing allows breeders to introduce new traits more precisely, and at a faster rate.
“With this approach, USDA seeks to allow innovation when there is no risk present,” US Secretary of Agriculture Sonny Perdue says in the statement. “Plant breeding innovation holds enormous promise for helping protect crops against drought and diseases while increasing nutritional value and eliminating allergens.” 
MIT Technology Review notes that transgenic crops—plants that contain artificially inserted genes from other species—will still be regulated.

See “The Unregulation of Biotech Crops

This announcement comes as good news to biotech companies using CRISPR to modify plants. According to Wiredthis move will “[shave] years and tens of millions of dollars off the cost of developing a designer plant.”
“Having this consistent position enables smaller companies and academic labs to form this ecosystem of innovation to bring options to consumers,” Federico Tripodi, CEO of Calyxt, a Minnesota-based biotech that has already developed soybeans that produce oil low in trans fats that can be cooked at high heat, tells Wired.  
Whether gene-edited plants require special labeling is still unclear. “Bioengineered foods are defined by containing genetic material that could not otherwise have been conventionally bred or obtained in nature,” Deepti Kulkarni, a former member of the FDA’s Office of Chief Counsel who currently works at Sidley Austin, a corporate law firm in the U.S., tells Wired. “If USDA is construing the language this way, there is some suggestive signaling that these products might not be subject to disclosure.”

Tuesday, March 27, 2018

Smart Water Management Matters

'Nature-based solutions' key to water management: UN report - World Water Day 22 March.

Wednesday, 21 March, 2018

Adobestock 102784556
Nature-based solutions can play an important role in improving the supply and quality of water and reducing the impact of natural disasters, according to the 2018 edition of the United Nations World Water Development Report.
Presented at the 8th World Water Forum this week by UNESCO Director-General Audrey Azoulay and UN-Water Chair Gilbert Houngbo, the study argues that reservoirs, irrigation canals and water treatment plants are not the only water management instruments at our disposal.
In 1986, the State of Rajasthan (India) experienced one of the worst droughts in its history. Over the following years, an NGO worked alongside local communities to set up water harvesting structures and regenerate soils and forests in the region. This led to a 30% increase in forest cover, groundwater levels rose by several metres and cropland productivity improved.
These measures are examples of the nature-based solutions (NBS) advocated by the latest edition of the report, ‘Nature-based Solutions for Water’. It recognises water not as an isolated element, but as an integral part of a complex natural process that involves evaporation, precipitation and the absorption of water through the soil. The presence and extent of vegetation cover across grasslands, wetlands and forests influences the water cycle and can be the focus for actions to improve the quantity and quality of available water.
“We need new solutions in managing water resources so as to meet emerging challenges to water security caused by population growth and climate change,” said Azoulay. “If we do nothing, some 5 billion people will be living in areas with poor access to water by 2050. This report proposes solutions that are based on nature to manage water better. This is a major task all of us need to accomplish together responsibly so as to avoid water-related conflicts.”
“For too long, the world has turned first to human-built, or ‘grey’, infrastructure to improve water management,” Houngbo said in the foreword of the report. “In so doing, it has often brushed aside traditional and Indigenous knowledge that embraces greener approaches. Three years into the 2030 Agenda for Sustainable Development, it is time for us to re-examine nature-based solutions (NBS) to help achieve water management objectives.”

Focusing on ‘environmental engineering’

So-called ‘green’ infrastructure, as opposed to traditional ‘grey’ infrastructure, focuses on preserving the functions of ecosystems, both natural and built, and environmental engineering rather than civil engineering to improve the management of water resources. This has multiple applications in agriculture, the greatest consumer of water by far. Green infrastructure can help reduce pressures on land use while limiting pollution, soil erosion and water requirements by contributing to the development of more effective and economic irrigation systems, for example.
Thus, the System of Rice Intensification, originally introduced in Madagascar, helps restore the hydrological and ecological functioning of soils rather than using new crop varieties or chemical products. It enables savings of 25 to 50% in water requirements and 80 to 90% in seeds while raising paddy output by 25 to 50%, depending on the region in which it is implemented.
It is estimated that agricultural production could be increased by about 20% worldwide if greener water management practices were used. One study cited by the report reviewed agricultural development projects in 57 low-income countries and found that using water more efficiently, combined with reductions in the use of pesticides and improvements in soil cover, increased average crop yields by 79%.
Green solutions have also shown great potential in urban areas. While vegetated walls and roof gardens are perhaps the most recognisable examples, others include measures to recycle and harvest water, water retention hollows to recharge groundwater and the protection of watersheds that supply urban areas. New York City has been protecting its three largest watersheds since the late 1990s. Disposing of the largest unfiltered water supply in the USA, the city now saves more than US$300 million yearly on water treatment and maintenance costs.
Faced with an ever-increasing demand for water, countries and municipalities are showing a growing interest in green solutions. China, for example, recently initiated a project called ‘Sponge City’ to improve water availability in urban settlements. By 2020, it will build 16 pilot Sponge Cities across the country. The goal is to recycle 70% of rainwater through greater soil permeation, retention and storage, water purification and the restoration of adjacent wetlands.

The importance of wetlands

Wetlands only cover about 2.6% of the planet but play a disproportionately large role in hydrology. They directly impact water quality by filtering toxic substances from pesticides, industrial and mining discharges.
There is evidence that wetlands alone can remove 20 to 60% of metals in water and trap 80 to 90% of sediment from runoff. Some countries have even created wetlands to treat industrial wastewater, at least partially. Over recent years, Ukraine, for example, has been experimenting with artificial wetlands to filter some pharmaceutical products from wastewater.
However, ecosystems alone cannot perform to totality of water treatment functions. They cannot filter out all types toxic substances discharged into the water and their capacity has limits. There are tipping points beyond which the negative impacts of contaminant loading on an ecosystem become irreversible, hence the need to recognise thresholds and manage ecosystems accordingly.

Mitigating risks from natural disasters

Wetlands also act as natural barriers that soak up and capture rainwater, limiting soil erosion and the impacts of certain natural disasters such as floods. With climate change, experts predict that there will be an increase in the frequency and intensity of natural disasters.
Some countries have already started taking precautions. For example, Chile announced measures to protect its coastal wetlands after the tsunami of 2010. The State of Louisiana (USA) created the Coastal Protection and Restoration Authority following Hurricane Katrina (2005), whose devastating impact was magnified by the degradation of wetlands in the Mississippi Delta.
Nevertheless, the use of nature-based solutions remains marginal and almost all investments are still channelled to grey infrastructure projects. Yet, to satisfy the ever-growing demand for water, green infrastructure appears to be a promising solution complementing traditional approaches. The authors of the report therefore call for greater balance between the two, especially given that nature-based solutions are best aligned with the Sustainable Development Goals adopted by the United Nations in 2015.
Coordinated by the World Water Assessment Programme of UNESCO, the United Nations World Water Development Report is the fruit of collaboration between the 31 United Nations entities and 39 international partners that comprise UN-Water. Its publication coincides with World Water Day, celebrated every year on 22 March.
Image credit: ©


Some thoughtful ideas that should be considered more often, even in Australia.  Unfortunately it often cuts across the old engineering concepts and old ideas are hard to change.  It also tends to have longer time frames to see change and involves more community groups to develop meaningful ideas.