The Tropics - Most Prone to Erosion - New Study Published

Those who live there are unlikely to be surprised by the conclusions in the study, but it does attempt to quantify those areas where it is most severe.

The north of Australia is among some of the most severely impacted areas but has some respite due to seasonal issues - little rain for a number of months in the middle of the calendar year helps reduce the problem.

The first world erosivity map provides a picture of those areas where it is worst.  And it is likely to get even worse with an  increase expected with changing climate and more frequent extreme rainfall.

Regions in the tropical climate zones suffer the greatest rainfall-related soil erosion, reports an international study.

The study, published last month (July) in Scientific Reports, has developed the first-ever Global Rainfall Erosivity Database and a Global Erosivity Map. It notes that while rainfall provides moisture critical for plant growth, it is also one of the prime causes of soil degradation, referred to as rainfall erosivity, which threatens food and water sustainability. 
[study available here in full - https://www.nature.com/articles/s41598-017-04282-8] 

For experts, model predictions of global erosivity are very important because they help assess risks as well as plan and implement effective soil mitigation and restoration strategies.

According to the study, erosion by rainfall remains poorly quantified despite its significance. This is because it is a complex event influenced by various factors including rainfall intensity, duration, amount and frequency — factors which are not captured in current erosivity estimates.

To model annual rainfall erosivity for different regions, the international team relied on rainfall data gathered from 3,625 stations scattered across 63 countries. Their analysis shows that annual mean rainfall erosivities for countries in the tropics are more than double the global average of about 2,190 megajoule millimetres per hectare per hour per year.
 
South America (particularly Brazil, Columbia and Peru), South-Eastern Asia (Cambodia, Indonesia, Malaysia, the Philippines and Bangladesh), the Caribbean, and Western and Central Africa have annual mean rainfall erosivities that are greater than 5,000 megajoule millimetres per hectare per hour per year.
 
Cold and dry regions like Canada, the Russian Federation, Northern Europe, Northern Africa and the Middle East have the lowest annual mean rainfall erosivity.
 
“The tropical forests and the monsoon zones (covering Amazonia part of Brazil, Central Africa and Southeast Asia) have intense rainfall but also excess monthly precipitation (greater than 1,000 millimetres for two consecutive months),” says Panos Panagos, study leader and scientific officer at the Joint Research Centre, European Commission. “The Mediterranean zone (a typical temperate climate zone) has seasonal rainfalls which are less intense than the ones in the tropical zones.”

“This is a great effort,” says Anton Vrieling, assistant professor of geo-information science and earth observation at the University of Twente, the Netherlands. However, he observes that calculating rainfall erosivity at different times in a year would be more useful than having an annual average value.
 
“In a given year, there are rainstorms of different intensity and duration. Other factors like the protective vegetation also vary throughout the year,” notes Vrieling.

With extreme rainfall events becoming more common as a result of climate change, soil erosion is expected to increase — leading to further impacts on agricultural production, and a greater contribution to disaster-related risks such as flooding and landslides.
 
Panagos says the emerging risks can be managed through good agricultural practices like reduced tillage, cover crops, grass margins and contour farming. 

Northern Australia - a small area by global standards is in the second highest zone, according to the mapping.  Small areas may of course be a little different.

Annual mean rainfall erosivity above the global average, by region

Region	Annual mean rainfall erosivity (in mega Joule millimetre per hectare per hour per year)
Global mean	2,190
Caribbean countries	8,000
South-East Asia	7,400
Western Africa and Central Africa	7,000
South America	5,874

Benefits of Using Compost for Erosion and Sediment Control

The following article was written recently by a colleague in the US [ Ron Alexander] and some content needs be seen in the context of that general location.

However, the broad implications are still relevant and even more so in the tropics with normally much greater intensity of rainfall, in comparison to temperate areas.  The experience of our own operations in the tropics on very large mining projects in Indonesia and tropical Australia adds to to the ideas written below here by the author, with surface applied mulches and composts being excellent erosion and sediment management options, even on slopes up to 1:1 - ie 45 degrees. Much better than silt fences!!

We even used chipped coconut husk pieces on some steep slopes very successfully, but commonly in Indonesia we used rice straw, a nominally waste material supplied by local farmers rather than burning it as waste in the fields after threshing the grain.  It was excellent, as mucous exuded from the straw helped bind the material together, allowing permeation of water through but not necessarily washing it all away.

Yes.......we needed some rechecks and repairs but for a very large area of bare slopes it was excellent, and certainly reduced erosion enormously at relatively low cost.

Mulch berms are now also commonly used on larger flat exposed areas near Darwin, with more extensive use on several large mining, construction and building projects in recent years.  Definitely a go to option that works well, is easily repaired when needed and it can tolerate heavy tropical rain, reducing high intensity overland flows.

Surface applied mulches can be very effective - consider them as a sensible option for your next erosion and sediment management project.

We offer ESCP plan development for projects and can assist you develop an appropriate solution. 
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9 Benefits to Using Compost for Erosion and Sediment Control

by Ron Alexander  8 January 2016

Credit: Erth Products

Erosion and sediment control. Although still considered relatively unknown in certain regions of North America, the use of compost in erosion and sediment control has been a very successful landscaping practice for over 25 years. 

Compost blankets (the application of a layer of compost on hill slopes), compost berms, and compost filter socks are incredibly effective, enhance the long-term quality of the soil, and, in the case of compost blankets, have excellent stormwater reduction advantages. These innovative techniques have been thoroughly proven through university research, and have been recommended for use by the USEPA. 

National specifications exist for these applications through the American Association of State Highway and Transportation Officials. (Go to www.alexassoc.net, then “Library of Articles,” and look under “Compost Specifications” to see the full specs.)

When used as a compost blanket, compost is typically placed on up to 2:1—and sometimes more severe—slopes at an application rate of 1–2 inches [25-50mm] in depth. 

This technique is used and is highly effective in reducing and slowing the sheet flow of water. 

Lesser application rates are possible in areas of lower rainfall accumulation and intensity, on less severe slopes, and where vegetation is to be established. Once applied, the woody fraction of the compost increases surface roughness and slows the flow of runoff, thereby making it less erosive, more likely to induce infiltration into the soil and reduce the transport of pollutants. 

In addition, the woody fraction absorbs the energy of the rainfall, preventing soil particles from dislodging (the first stage of soil erosion), while the finer fraction beneath it absorbs a substantial volume of moisture, and is optimum for plant establishment and growth. Research completed at University of ­Georgia illustrated that a 2-inch[50mm] application of compost onto a slope could absorb and hold 1–2  [50mm]inches of rainfall.

Further, the unique properties of the product allow for extensive rooting of the grass and other vegetation, locking the blanket to the slope and protecting the soil beneath it. 

It should also be noted that compost blankets are effective with or without vegetation, but application rates of compost can often be reduced if it is applied with vegetation. University research consistently illustrates that compost blankets not only constantly outperform hydroseeding and conventional erosion control blankets (e.g., rolled fabric) in vegetation establishment, but also more effectively reduce stormwater runoff volume and peak flows, as well as total sediment and nutrient loads (Faucette et al. 2005; Faucette et al. 2007; and Faucette et al. 2009, “Large-scale performance and design…”).

Research performed for Portland Metro, an environmental regulatory body based in Portland, OR, and the USDA ARS further illustrated that yard trimmings compost was capable of not only controlling erosion, but also of filtering, binding, and degrading contaminants from the stormwater passing through the layer (Faucette et al. 2013; Faucette et al. 2009, “Storm water pollutant removal performance…”).

The benefit of using a compost blanket lies in its ability to:

• act as a buffer to absorb rainfall energy,
• reduce wind and water erosion,
• stimulate microbial activity to increase decomposition of organic materials in the soil thereby adding to the soil structure,
• prevent soil compaction and crusting, thereby facilitating percolation,
• slow the flow of water over the surface of the soil,
• capture and retain moisture, reducing soil moisture loss thereby facilitating plant growth,
• provide suitable microclimate for seed germination,
• in areas with cold winters - capture blowing snow to increase the insulating effect of winter protection, and
• improve soil texture (Story et al. 1995).

Compost berms and filter socks are “3D” filters possessing huge sediment and biofiltration capabilities. 

Where the berms are used in sheet flow conditions, the filter socks (think pantyhose filled with coarse compost) can also be used in concentrated water flow situations. 

This is because filter socks can be staked into place, and the compost media is contained within a mesh netting material. 

Although both compost berms and filter socks are used as perimeter control devices for sediment, installed around the borders of construction sites and at the top and bottom of slopes, the filter sock technology is much more versatile (see www.filtrexx.com). 

They can even be used around stormwater inlets and to build “living” walls. 

One of the most important research findings pertaining to compost filter berms and socks, is that they are much more effective in capturing fine particles of sediment, which are not captured as efficiently by other more conventional sediment control devices (e.g., silt fences). 

This is very important in that fine particles of sediment have the potential to be much more damaging to the environment, since they transport further and stay in suspension longer, and also contain a greater amount of chemical contamination (e.g., petroleum hydrocarbons, heavy metals, nutrients) than larger particles of sediment.

The use of compost in erosion and sediment control projects has expanded significantly since the adoption of the National Pollutant Discharge Elimination System (NPDES) Phase II regulation for construction activities in the USA. 

This regulation requires that construction sites of 1 acre or greater to have erosion and sediment control plans in effect on a daily basis using prescribed best management practices (BMPs).

Composting - Vital for Better Soil Health, Fertility and Reducing Erosion

Composting reduces waste and builds healthy soil to support local food production and protect against the impacts of extreme weather, from droughts to heavy rainfall. That’s the message of two new reports from the Institute for Local Self-Reliance (ILSR):

State of Composting in the U.S.: What, Why, Where & How <http://www.ilsr.org/state-of-composting/> and

Growing Local Fertility: A Guide to Community Composting<http://www.ilsr.org/size-matters-report-shows-small-scale-community-based-composting/>

Compost is the dark, crumbly, earthy-smelling material produced by the managed decomposition of organic materials such as yard trimmings and food scraps. Compost is valued for its ability to enhance soil structure and quality. It adds organic matter to soil, improves plant growth and water retention, cuts chemical fertilizer use, and stems stormwater run-off and soil erosion. In the U.S., 40 million hectares (28% of all cropland) are eroding above soil loss tolerance rates, meaning the long-term productivity of the soil to support plant growth cannot be maintained.  

It might be worse comparatively in Australia, and China certainly has major problems!

compost production- commercial scale

Applying a meagre 12mm of compost to the all of the severely eroded cropland in the USA would require about 3 billion tonness of compost,” says Brenda Platt, the lead author of both reports and director of ILSR’s Composting Makes $en$e Project. “There is not enough compost to meet that need.  No organic scrap should be wasted.”

Compost also protects the climate:  it sequesters carbon in soil and it reduces methane emissions from landfills by cutting the amount of biodegradable materials disposed. (Methane is a greenhouse gas with a global warming potential 72 times more potent than CO2 in the short-term.) A growing body of evidence demonstrates the effectiveness of compost to store carbon in soil for a wide range of soil types and land uses.

Yard trimmings composting programs are fairly well developed in the U.S.

Of the 4,914 composting operations identified in the U.S. for State of Composting in the U.S., about 71% compost only green waste / yard trimmings (based on 44 states reporting). Food scrap recovery is slowly growing. More than 180 US cities and counties are now collecting residential food scraps for composting, up from only a handful a few years ago.  “There is more demand for composting, especially from businesses and institutions that want to source separate food scraps and not throw them in the landfill,” says Nora Goldstein, Editor of BioCycle, which conducted the state-by-state assessment of composting infrastructure and policies, “We not only need more infrastructure to compost these materials, we need more infrastructure to manufacture high quality compost that our soils — and climate — desperately need.”

 

compost berm used in erosion control

State of Composting in the U.S. is the first comprehensive review of composting basics, national and state statistics, job generation data, model programs, and policy opportunities.

The report calls for a national soils strategy and for new rules and programs to grow composting, especially at the local community level: including streamlined permitting for facilities, training programs, technical and financing assistance, strong recycling and composting goals, disposal bans, compost procurement policies, and more.  “The beauty of composting is that it can be small-scale, large-scale and everything in between,” says Brenda Platt. “Why send resources out of the community when our neighbourhoods need food and our soils are starved for organic matter?”

I would imagine that the report for Australia and the NT in particular would be quite similar.  However, around Darwin mulched green waste is widely used in domestic areas but much less so commercially and for landscape rehabilitation where it can be especially useful in restarting organic processes on damaged soils.

A sneak peek inside State of Composting in the U.S.: What, Why, Where & How:

·      Section 1, What Is Composting and Compost, describes the composting process, what materials can be composted, composting systems, and the many uses for compost.

·      Section 2, Why Compost?, identifies the key benefits of composting to create jobs, protect watersheds, reduce climate impacts, and improve soil vitality.

·      Section 3, Where Is Composting Happening, provides a national snapshot of composting infrastructure, current policies, and model programs that could be replicated.

·      Section 4, How to Advance Composting, outlines new rules and initiatives to grow composting, and describes the importance of a diverse and locally based infrastructure.

ILSR’s companion report, Growing Local Fertility: A Guide to Community Composting, features successful community-scale composting initiatives, their benefits, tips for replication, key start-up steps, and the need for private and public sector support. 

Produced by ILSR’s Composting Makes $en$e Project and the Highfields Centre for Composting, this guide highlights more than 30 diverse urban and rural small-scale locally based composting programs in 14 states and the District of Columbia.  They include schools, pedal-powered collection systems, worker-owned cooperatives, community gardens, and farms employing multiple composting techniques.

To download both reports, visit  www.ilsr.org/initiatives/composting

Soils Benefit if Compost or Mulch is Used

Twelve Benefits of Compost

 Many scientists and farmers speak highly about the use of compost and mulch in soils.  There are often soil and crop improvements attributed to using these organic additions but are they real benefits?

While there is a certain amount of quackery over many soil additives, with some very dubious clams being made for them, it is now considered that there is a reasonably comprehensive set of truisms that can be attributed to compost use, with compost consderd in a broad sense to also include organic mulches.

These benefits and soil improvements are seen in temperate regions in the US, Europe and Australia as well as in tropical regions, with the latter often seeing very big improvements as the soils are tending to be lower in soil organic matter anyway.  Small additions of organic materials can mean big crop performance improvement.

The twelve well recognised benefits of compost are listed below. 

The following list of compost benefits have been approved by the Association of American Plant Food Control Officials (AAPFCO). This organization is made up of state Department of Agriculture regulatory officials from every state in the US. These claims are permitted to be made, and are considered as valid, on compost labels, literature and websites in the US and are also relevant elsewhere.

Compost -  

a. Improves soil structure and porosity – creating a better plant root environment;

b. Increases moisture infiltration and permeability, and reduces bulk density of heavy soils – improving moisture infiltration rates and reducing erosion and runoff;

c. Improves the moisture holding capacity of light soils – reducing water loss and nutrient leaching, and improving moisture retention;

d. Improves the cation exchange capacity (CEC) of soils;

e. Supplies organic matter;

f. Aids the proliferation of soil microorganisms;

g. Supplies beneficial microorganisms to soils and growing media;

h. Encourages vigorous root growth;

i. Allows plants to more effectively utilize nutrients, while reducing nutrient loss by leaching;

j. Enables soils to retain nutrients longer;

k. Contains humus – assisting in soil aggregation and making nutrients more available for plant uptake;

l. Buffers soil pH.

There are many articles and newspaper stories about the benefits of compost - so if you are not using compost or any other organic additions such as mulch, why not?  The photo shows mechanised compost production using a row turner.

In the tropics where rainfall is often in short higher intensity storms, surface mulches and composts provide a very effective surface barrier that prevents the dislodging of soil surface particles caused by the energy of impact of rain drops - this dislodgement commences the process of soil erosion.  A mulch cover can greatly reduce that problem while also controlling the infiltration of the rain.   "Cover"is a significant term in the universal soil loss equation [ USLE] used to calculate erosion, and is a factor that can be easily modified - as distinct from some of the other factors.  And soil cover is why dense grassland or rainforest is less prone to erosion.

The carbon in the organic materials often remains in the soil for some time so it also contributes to sequestring carbon, although not always for really long periods. [ that is another complicated issue - you could read about biochar or terra preta soils]
Surface mulch and compost are great contributors to better soils and the products grown in them!. 

Food Security Critical for China

A recent post highlights that Australia is selling off resources to China - land resources for agriculture especially.

[see - http://abovecapricorn.blogspot.com/2011/09/should-australia-be-selling-farm.html ]

Not all are happy over this issue.

China, as distinct from Australia has some clear policies around food security and imports of minerals, with a distinct focus on extra-terrritorial acquistion of the means of production - of both.

See more here - http://qcl.farmonline.com.au/news/nationalrural/agribusiness-and-general/finance/china-aims-for-selfsufficiency/2268434.aspx?storypage=0

In this article Prof Mike Berrell, Director WADEmatheson and Executive Dean, Holmes Institute, Australia, an expert on Chinese business practices says Australia’s lack of strategy and vision for a sustainable agricultural industry, was flagging in comparison to China’s global approach.

He said for the Chinese to be purchasing prime agricultural land outright entails risks for Australia due to loss of control in what is emerging as a global strategic industry.

This would be especially the case if the ventures were 100 percent Chinese invested, he said.

Despite China's recent efforts to reduce carbon emissions, China's current commitment to sustainability does not extend to agricultural practices, he said.

“Joint ventures in the area would be preferable to 100 percent Chinese foreign ownership - the latter of course suits China,” he said. “Australia must be absolutely clear about how such ventures are to move ahead and establish strict guidelines for ownership - perhaps make sustainable agriculture a strategic industry is the same way has China has its “strategic industries”, which fall outside normal investment guidelines.”

A significant issue in this is that most players from China are state owned, effectively an arm of the sovereign government of China. While other parts of the world have previously invested in Australian rural properties and industries, and many still do, [think the UK and the USA] they are almost always privately owned companies, or private individuals, and from countries where government intervention in industry is minimal.

This is a serious issue for Australia, a nett food exporter, with other sovereign countries owning our food production resources.

The image also shows that it is not just China - an example of the options that Singapore is pursuing in a similar fashion.

Should Australia be concerned over the whole theme of extra-territorial agriculture?

Sediment Socks Work Better with Compost

Compost socks

Using a sand filled coil as an environmental salvation tool is quite common. Seen round the streets and building sites these long thin “socks” are a common tool for erosion and sediment management in almost any site where sediment movement could be expected.

Traditionally, it was sand that went into these socks.

But performance can be enhanced, by the simple change from sand to compost or fine pasteurised mulch products. That is a simple and easy change to make, and it may cost nothing different.

An even better option can be to add some of the bioremediation type products available that have oil and hydrocarbon remediation attributes. There are a few brands available, but an easy one available in Australia is Enretech -1 , a powdered product that can be added to the sand or even the mulch mix.

Fine hydrocarbon materials, metals and rubber , commonly moved off roads in wet weather will be trapped by the socks and the hydrocarbons bioremediated, avoiding their movement into waterways.

The mulch is superior to sand in capturing the hydrocarbons, and as good or better in slowing sediments in general.

And costs about the same as sand filled socks.

So.........think about the issue and make the switch to a better sediment sock!

Additional details on installation and use are here -http://cfpub.epa.gov/npdes/stormwater/menuofbmps/index.cfm?action=factsheet_results&view=specific&bmp=120

and are applicable almost anywhere around the world.

Camel Burger -To Go, Please

A lot of camels have been exported from central Australia, averaging around 3000 a year, yet camel populations continue to grow........exponentially........well almost so it seems.

There are a lot, and they mostly are considered as a feral animal issue. Their numbers are currently around one million. And continuing to rise, such that environmental degradation is a very serious issue as well as damage to towns and rural properties. A $19 million project to cull camels has been proposed.[ http://www.cbsnews.com/stories/2009/11/26/world/main5786556.shtml]

Quite a few have tried before to establish an overseas or even local market for the meat. It just has not been successful, and the slaughter process is often the problem. Camels require a specialised abbattoir, sized for them.

This time round, maybe there is more chance of success.

The proposal is to establish an abbatoir at Port Pirie, trucking the camels in for halal slaughter, then export chilled or frozen boxed meat. The proponent has established credentials in the middle east market for other meat products - sheep, goat and cattle so outlets are in place, plus there has been the development of some fast food camel burger outlets in Dubai, with another planned possibly for Abu Dhabi.

It might just be different enough to work.

read more here - http://online.wsj.com/article/SB10001424052748704628404576265783864754552.html

It would assist with reductions in camel numbers in Australia, provide jobs and income for remote areas and feed the Middle East. It might even be considered as organic camel meat. Maybe it has a chance.

UPDATE on 19 May

Read more here - http://www.enn.com/top_stories/article/42712

when Australian stories make it to this level, it is considered big news.

Erosion and Sediment Control with Recycled Organic Waste - Berms

The following is very pertinent to the Top End of the NT today, as we experience a major 100mm per hour storm across the Dariwn region.

Where is your soil going today??

Erosion and sediment control, particularly on civil construction sites often seems to start and end with using a silt fence.

While silt fences can be effective, to be so, they require correct installation, and ongoing maintenance. While there are machines to install silt fencing [yes, they do exist!] rarely have I seen one in Australia, and especially on smaller civil works sites, they are, as they say, as rare as hen’s teeth!

Installing a silt fence is a tedious job, particularly the preparation of the footings, in which a lower area is buried, as well as refilling the trench. Mostly, and somewhat sadly, it is often done poorly, and the silt fence is often relatively ineffective.

In Australia with high summer storm rains, and especially so in the tropics, it is quite common to see a silt fence struggle with high rainfall intensity, and they sometimes breach. There are other options that can be simple and easy to install, and repair if necessary.

Top among the options is using a mulch or compost berm or contour bank. Many regions have mulched green waste available, and creating a berm is relatively simple using readily available on site equipment such as a bobcat or small backhoe. Accessing the greenwaste is often through the local council, or sometimes even using on site available cleared green materials can be useful too.
Ideally, pasteurised mulch is the preferred material, with coarse materials suitable. Ground woody waste, even small woody branches are usable. However, where pasteurised mulch is NOT available, unpasteurised mulch can do, although there will be a need to spray and kill any weeds that emerge within the berm – glyphosate is the normal option. Plants developing from the pasteurised mulch are very slow to almost none, although a few plants might be expected from blown in seeds, after a while.

There are some excellent resources on line, but the simple plan is to develop several berms across a slope, on the contour. They should be lightly keyed into the ground, often by building on a ripped base area or similar simple disturbance. Unlike an earth bank, they are supposed to be porous........just that all the water does not flow through at once, and sediment is collected and deposited along the way.

More information here:
http://www.caes.uga.edu/Publications/displayHTML.cfm?pk_id=6296 from Georgia in the US; a sub tropical region of the US

http://www.deq.state.or.us/wq/stormwater/docs/nwr/ephcompost04.pdf

http://cfpub.epa.gov/npdes/stormwater/menuofbmps/index.cfm?action=factsheet_results&view=specific&bmp=119 - a very comprehensive overview of berm use and construction

http://www.creativeearth.net/stormwater.html - shows how to build a system


When the project is completed, the berm can then be used as part of the organic materials often used on site as part of the landscaping, or often left in place in small drainage lines to continue to function until there is improved cover on the nearby soil areas.

They work extremely well, are cheap to construct and maintain, and VERY environmentally friendly!

Restoration of the Loess Plateau in China

Things tend to be done on a large scale in China..............new cities, new roads and now landscape restoration.

The loess plateau in China has traditionally been a key part of productive agriculture, but it has suffered some terrible erosion in achieving some of the production and many many areas are now totally lost to agriculture. There are many images on the net of this damage, and I have previously blogged about it. But all may not be lost.

The article below is reproduced in its entirety...........and worth reading.

The concept was, to my best knowledge, originally espoused by CSIRO scientists in the early 1980s.......as landscape ecology. Especially relevant to arid zones, and at that time after a long drought, but also for any disturbed landscape in which the key is to get basic biology re-established in the soil. Often low forms of plants establish first, lichens, worts etc along with microbes......and things go from there as organic matter starts to accumulate.

Needless to say, add organic matter and you get a big boost, and this naturally happens in minor soil depressions where organic residuals accumlate, but a liberal dose of added mulch is just fine!!!

We used similar technology to deal with erosion and soil restoration on a major mine development in Indonesia in the late 1990s, by adding significant organic matter to help kickstart plant re-establishment in a monsoonal environment where erosion control was also a key factor in its success.
As the article says:
"It starts as a physical intervention, but it becomes a biophysical intervention once the biology stops gravity being such a destructive force,” Mr Liu said.
“The principle is to start the accumulation of organic matter and total vegetation coverage, and at a higher level understanding the role of biodiversity.”
“It’s an advance over the concept of simply tree planting, which is simplistic and doesn’t talk about other factors like soil condition or other forms of vegetation.”

This is the key issue............absolutely!


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Restoring China's lost Loess Plateau
MATT CAWOOD 11 Jun, 2010 10:18 AM

ABANDONED 1000 years ago by one of the first civilisations because of land degradation, China’s Loess Plateau has become the focus of a modern land restoration effort that has transformed agriculture and the local environment.

Key to restoration of 35,000 square kilometres of the 640,000 sq km plateau was the surrendering of farmland to purely ecological plantings.

According to a film made by soil scientist John Liu, in Australia last week to talk to the National Business Leaders Forum, local farmers strongly resisted the idea of giving over farmland to trees, but were persuaded by compensation payments on land taken permanently out of production.

As reported in Mr Liu’s film, Hope in a Changing Climate, available on the internet here , engineering landscapes and re-planting vegetation across key ecological recharge areas has changed the environment in ways that have lifted farm incomes threefold.

The Loess Plateau, which takes its name from the mineral-rich wind-borne sediments that make up much of its soil, was for several thousand years the base of China’s Han people.
It is thought the plateau was the second place on Earth to have a settled agriculture based on cultivation of the soil, after Mesopotamia.

Mr Liu said that China’s extensive written records show that over thousands of years, the plateau progressively lost its ability to sustain the Han. Their primitive agriculture degraded the landscape and destroyed the ecology, until about 1000 years ago the Han power base shifted east to what is now Bejing.

The plateau has since earned the distinction of being the most eroded place on Earth. Eroded loess provides the “yellow” in China’s Yellow River.

In 1995, when Mr Liu was invited to record the initial stage of the landscape restoration project, the plateau was being farmed at a subsistence level by desperately poor farmers who unwittingly compounded their own ecological troubles.

According to Mr Liu, Chinese scientists calculated the cost of sediment loss against the cost of restoring the landscape, and decided that restoration would be a quarter of the cost of allowing degradation to continue.

Less wealthy in 1995 than now, the Chinese borrowed US$500 million from the World Bank and set about rebuilding the landscape - mostly by hand. In typically picturesque Chinese terms, the project aimed to give the eroded hills “a hat, a belt and shoes at their feet”. That translates to tree cover on the upper slopes, farming terraces on the lower slopes, and dams in the valleys.

Massive landscape engineering was involved in the transformation - an approach unlikely to get much traction in Australia - “but the results are stunning”, Mr Liu said.

At one level, the project is an endorsement of the “front of pipe” approach to water management floated earlier this year by Australian landscape campaigner Major-General Michael Jeffery of Outcomes Australia.

On the Loess Plateau, more porous vegetation-covered soils and the flat terraces now catch and rainfall that once ran off the plateau during the rainy season, leaving it in drought during the dry season.

Water captured by the soil instead filters down through the terraces, fuelling crops. Waterways run clear, and farm productivity has soared.

Better productivity on the slopes, and the dams below, have allowed greenhouse agriculture to flourish in the valleys, extending the income-making opportunities for the local communities.
“It starts as a physical intervention, but it becomes a biophysical intervention once the biology stops gravity being such a destructive force,” Mr Liu said. “The principle is to start the accumulation of organic matter and total vegetation coverage, and at a higher level understanding the role of biodiversity.” “It’s an advance over the concept of simply tree planting, which is simplistic and doesn’t talk about other factors like soil condition or other forms of vegetation.”

Since 1995, Mr Liu has travelled to 60 countries looking at landscape regeneration techniques. He is a founder of the Environmental Education Media Project, which numbers the World Bank, Rockerfeller Foundation and Syngenta among its sponsors.

Although only briefly in Australia, Mr Liu was introduced to the environmental benefits of time-controlled livestock grazing practices in use here.

Also see here with more photos -

http://qcl.farmonline.com.au/news/nationalrural/agribusiness-and-general/general/restoring-chinas-lost-loess-plateau/1854215.aspx?storypage=0

[article reproduced from the Land online]

Soil Stability Enhanced by Using No-Till Agriculture

Nothing new in that statement, you say.

For users and advocates of the conservation farming approach, it would seem to be old knowledge. But similar outcomes might also be expected for areas where similar practices are now also being used. For example, use of recycled organics in transport corridors, rehabilitating mining sites with similar products and similar off farm uses.

A recently concluded 19 year study across a wide region of the US has delivered some quite definitive results. Using plant residues on the soil surface, along with no till farming delivers significant improvements in soil stability and resistance to erosion.

The "cover" term in the universal loss loss equation has been so modified as to bring modifications to soil loss. And as said above, the same should apply to other areas where surface cover with organic materials is practised.

read more here - http://www.plantmanagementnetwork.org/pub/cm/news/2010/SoilStability/

The critical part is this - "No-till stores more soil carbon, which helps bind or glue soil particles together, making the first inch of topsoil two to seven times less vulnerable to the destructive force of raindrops than ploughed soil.

The structure of these aggregates in the first inch of topsoil is the first line of defense against soil erosion by water or wind. Understanding the resistance of these aggregates to the erosive forces of wind and rain is critical to evaluating soil erodibility. "

Get your soil cover in place.

Especially so in the tropics where erosion impacts from high intensity storms can create erosion problems very quickly. And it is a wise practice for many civil engineering developments as well.

Could Farming in the Tropics Promote a Killer Disease?

This is the premise being actively promoted in a new study of the disease meliodosis, based on results from the Northern Territory of Australia. Meliodosis is deadly........without active and well managed treatment you die. At least in the NT, there is a good quota of experience with the disease and mortality rates are now around 20%. Still, that is very high.

The disease also occurs in SE Asia in the tropics - Thailand, Laos, Malaysia etc, and is something to be mindful of when involved in agriculture in these areas.

Read the press release.........

Gardening and farming in the Australian tropics creates an environment "ideal" for the spread of a killer bacteria, a scientist has warned. Darwin-based researchers have worked to identify the soil types favoured by the bug Burkholderia pseudomallei, which is now at the centre of an outbreak of a pneumonia-like illness in the NT capital. Ten people have been infected, and two have died, from the illness Melioidosis since the wet season began late last year.

Dr Mirjam Kaestli says the bacteria was thought to favour damp soil and areas where there was standing water, but her research also found it thriving in household lawns and dry paddocks across rural Darwin. "These findings raise concerns that pseudomallei actually might spread due to the influence of our land management changes," says Dr Kaestli, who is a research fellow at the Tropical & Emerging Infectious Diseases Division at the Menzies School of Health Research. "Residential gardening and farming generates conditions which are ideal for the proliferation of these pseudomallei.

"We primarily found the bacteria in irrigated lawn areas like on residential properties ... also soil disturbance caused by livestock animals seem to increase survival chances for pseudomallei in areas otherwise not favourable."

It is thought the constant aeration of paddock soils from hoofs, along with raised acid levels from urine, encourage the growth of the bacteria.

The Royal Darwin Hospital treats up to 40 cases of melioidosis every wet season and, while it has a 20 per cent mortality rate this has halved over the past 15 years because of improved diagnosis and treatment. It is listed as an emerging disease, with cases rising in Thailand, and Dr Kaestli warns there were concerns the number would also increase in Australia.

Melioidosis cases have been detected as far down the eastern seaboard as Brisbane.

"Because we have seen this association with disturbed soil, and because there are more and more developing of previously undisturbed area, I would not be surprised if we are seeing higher numbers in the future," she said. People with type-2 diabetes, chronic lung and renal disease, heavy alcohol consumers or those who use of immunosuppressant drugs are known to carry an increased risk of contracting Melioidosis. Dr Kaestli said people in the tropical areas should take precautions by wearing shoes when working in the garden, washing their hands later with an anti-bacterial and taking extra care to keep cuts dirt free.

Her study is published in the journal PLoS Neglected Tropical Diseases.

Africa Saved by Organic Food - Really??

In the 1970s and 80s, two well renowned CGIAR Centres - IITA and ICRISAT had major programs originally in India and then in Africa to examine crop production. A focus of much of the work was plant establishment and performance in the heavy but erratic rains of the monsoonal and similar tropical areas. Crucial issues to improved performance and crop yield were the use of soil mulches [often legumes] to reduce erosion and lower soil temperatures to mangeable ranges in which seeds could germinate and establish. Mulch also enabled soil moisture to be retained and thus allowed better establishment. Without satisfactory establishment and early growth, crops would fail to perform.

This system was very successful, and similar modified large scale systems have been developed for the tropics in Australia and Brazil, for example. Part of the Australian system involved a ley farming phase in which tropical pastures were used for animal grazing with the leguminous residuals aiding the next crop establishment, in the manner above.

This is not organic farming, although undoubtedly, using organic residuals over time will build soil carbon and enhance soil quality. In Africa, the tropical soils are often nutrient deficient, and yields are restricted by poor plant nutrition. Finding and adding those plant nutrients at low cost is near impossible, except for very small restricted areas - for example home gardens. Yes, it is undoubtedly true that soil mycorhiza can allow release of nutrients from otherwise non available sources, but the amounts are unlikely to be adequate to completely supply enough to grow good crops.

A new media release by the organic lobby in Australia uses a recent UNEP article that espouses the view that organic agriculture will radically improve African agriculture. Organic agriculture to be the saviour of Africa!

I am not so sure, except for those smaller areas. Yes, some of the soil carbon principles are important. BUT........this is not new for the tropics; it is nearly 40 years of old news, written up and published in eminent journals and as layman's reading, and acted on around the world in the tropics.

Read the media release and the link to the UNEP article.

It's Official: Organic farming provides answers to feeding Africa

A major study by the United Nations Environment Programme (UNEP) concludes organic farming offers Africa the best chance of breaking the long inherent cycle of poverty and malnutrition. (1)

Research conducted by UNEP suggests that organic, small-scale farming can deliver the increased yields which were thought to be the preserve of industrial high-tech farming, in addition to reversing environmental and social damages, leading to greater food security.

The head of the UN's Environment Programme, Achim Steiner, says the report "indicates that the potential contribution of organic farming to feeding the world may be far higher than many had supposed."(1)

Dr. Kristen Lyons is a senior lecturer at the School of Biomolecular and Physical Sciences at Griffith University (QLD) and the director of Mukwano Australia, a non-for-profit group supporting the development of health care services in African organic farming communities.

"Organic agriculture offers an alternative - and sustainable - future for African farmers," says Dr. Lyons. She says the report provides a clear direction for reducing the current crisis in agriculture and food systems in developing countries - organic, all the way. "It demystifies the assumption that genetic engineering and other high-tech approaches to farming are required to feed the world.
"In contrast, it is organic farming systems that have demonstrated the greatest potential to feed the world's one billion starving people, and to ensure the long term sustainability of global food production," she says

The UNEP report proposes that African communities need to look to alternative methods of farming as genetic engineering is prohibitively expensive and therefore out of reach for most African farmers. (1)

Organic farming in Africa has lead to benefits to the natural environment, with the UNEP report showing a 93 per cent of case studies reporting benefits to soil fertility, water supply, flood control and biodiversity. (1)

Also, when sustainable agricultural practices, which covered a variety of systems and crops, were adopted, average crop yields increased by 79 per cent. (1)

Overall, the report found an increase in organic farming in Africa could lead to savings on production costs (due to no expenditure on synthetic inputs), promote economic viability and encourage food self-reliance. (1)

Data: (1) United Nations Conference on Trade and Development United Nations Environment Programme, Report: UNEP-UNCTAD Capacity-building Task Force on Trade, Environment and Development, Organic agriculture and food security in Africa, Unite Nations, New York and Geneva, 2008
[media release by BFA Australia]
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Of course this report is in contrast to recent publications about the need to boost food production, and fast in these areas.

The truth probably is somewhere in the middle. But I doubt, given the wide range of problems that interfere with accumulation of quality organic residuals in Africa, that enough can be accumulated to go totally organic. Embracing the work of the 70s and 80s to enhance establishment and reduce erosion is a vital start to improvement. The technology has been around for some time; getting it adopted widely is more difficult, and often social and machinery issues can interfere with adoption of promising technolgies.

BUT....it is not organic farming, as most people would define it.

How Will Food Production Change over the Next 25 Years?

http://news.bbc.co.uk/2/hi/science/nature/7795652.stm

This link will take you to a recent article on food production systems and the cry for a more efficient way of producing food. It is uk centric, but does have some relevance world wide. I am not sure that some of the claims regarding environmental damage and similar issues are as clear cut as the passing remarks indicate.

Cities require huge volumes of food to be transported into and through them. With Asia about to develop even more mega cities [ 9 million and up population], this situation is about to get a lot worse. The sheer logistics of providing food for those cities is mind blowing. If you have ever crossed the causeway between Singapore and Johore Bahru and noted the lines of trucks carrying food, that gives an idea of the logistical problems of feeding a city, in this case Singapore that has effectively outsourced ALL food production.

Two recent Australian ventures are tackling some of these issues by building monstrous greenhouses, for year round production, essentially hydroponically, or close to that by various soilless cultural options. One is in the New England area - 20 ha of tomatoes - year round, and the other announced last week will be on the South Coast near Sydney in an even larger operation through a joint Dutch / Australian venture. These sophisticated growing systems have superior management of water, compost, plants , disease and nutrition and aim to reduce growing costs while enhancing environmental performance. Both rely on Australia's abundant sunshine which allows year round production. Both are on major link roads to metropolitan areas, with excellent transport connections.

Some Australian agricultural science operatives have proposed green roof and wall systems for FOOD production, not just for carbon dioxide capture and heat reduction on the inevitable concrete surface, using a few ornamentals. The food production option has a huge amount of merit, as does the revival of the household veggie patch, which was common in the pre 1970s periods in many suburban yards - world wide.

There is a need to also get real about form and function in the food we choose and eat. It might be nice to consider that every carrot must be equal in size, shape and colour......but does it always matter? In some cases it might....odd shapes can hide disease at times, but in most cases it is IRRELEVANT to taste. Having a few less than perfect forms means far less wastage of produce to meet unrealistic at times consumer demands. Unless they will pay enormous prices - a bit like the high priced "perfect" fruit used for Japanese gifts.

While the article referred to above makes a low key plea for organic production, the reality is that certified organic production will NOT produce enough to feed the masses. A recent article on the "Politics of Food" by an Oxford professor debunks that myth. But we will have to do more with organic residuals - compost manures and related materials, as that is where many of the residual nutrients finish up, and those nutrients can be reused to grow additional food. Getting them back to the production areas is an issue in itself, unless production areas change. In Australia the vineyards have made enormous progress in use of efficient watering systems, organic compost and semi organic production - saving money and doing it better.

On this issue of food availability, it is also noted that the worlds food deficit areas are mostly where the abject poverty and malnutrition occurs. And the Politics of Food book, rightly infers that producing more in those areas, with more science and even a good dose of GM crops, and solving a few conflicts would aid that issue enormously.

Subtly, food production areas are changing in Australia, with poultry production relocating away from outer metropolitan city areas back to rural areas closer to the production areas for grain, and processing is moving too, to where the birds are grown. It is cheaper to produce both eggs and poultry in those areas close to grain areas and move the finished product. Moreover, the residuals are being used on land around the poultry production areas to grow hay and other crops. Sensible thinking.

We in Australia do not have the monster cities of Europe, Asia or the Americas, and suitable agricultural land is reasonably available, except that many of the great horticultural areas with good soils close to major cities are being converted to land for houses. That has been happening for many years. And it may not be stoppable. In Australia availability of water may be an issue, although treated effluent is potentially suitable for some horticultural uses eg open space irrigation, even to be able to free better water for food production. Do you realise that Sydney, developed when a single use of stored dam water was acceptable, places about 90% of the cities effluent into the adjacent ocean, although that is being reduced - albeit quite slowly.

But we as a society need to think through these type of choices. If regular food production is forced further away from consumers, will it be come too expensive? You cannot grow mangoes in Melbourne; they will always need to be transported from production areas in the tropics. That inherently makes them costly in Melbourne.

As more Australians live in the tropics however, a diet change to locally grown produce might be a good option. That might mean asian vegetables - and some are very good- rather than the usual temperate peas, parsnips and potatoes. And all of the last three will always be imported to the Australian tropics - we do not have a highland area nearby to grow them although some may argue the Atherton Tableland might fit - but not really high enough.

Think of your choices......

The True Value of Soil Carbon

Carbon trading systems must be careful not to undervalue soil carbon, according to a leading soil scientist, because the true productivity value of soil carbon to farmers may be hundreds of dollars per tonne.

Dr Rattan Lal, a professor and director of the Carbon Management & Sequestration Center at Ohio State University, was a keynote speaker at last week's Carbon Farming Conference in Orange, NSW, hosted by the Carbon Coalition. He indicated that in order to commoditise carbon, a realistic value must be established that reflects its value to farmers and society.

When Dr Lal looked at humus, of which carbon is the main component, and teased out the nutrients and water typically held within a kilogram of humus, he arrived a value of US$250 a tonne on today’s prices. BUT…..initial estimates of carbon's starting value under the Australian Carbon Pollution Reduction Scheme (CPRS) are around $20 per tonne. That is a big disparity!

Farmers, and society at large, also benefit from the fact that soils with high levels of organic carbon (humus, as shown in the photo) are resistant to erosion, deliver less pollution to waterways, biodegrade chemical pollutants and buffer climatic extremes.

"Whether the trading process can provide farmers with all of that value remains to be seen, but undervaluing a resource can lead to its abuse " Dr Lal told the conference via an internet video link.
If soil carbon ultimately earns a high price, it raises questions about the value and use of crop residues that contribute to soil carbon formation. Cellulosic ethanol plants that will draw on crop residues are being built in the United States, and the technology is under discussion in Australia.

However, Dr Lal observed that the world's estimated four billion tonnes of annual crop residues should play an important part on the farming process. In Dr Lal's estimation, those global residues contain 30 million tonnes of nitrogen, 3.5mt of phosphorus and 47mt of potassium—and crop residue contains about 40pc carbon.

His initial studies were mainly concerned with conservation tillage and use of crop residues for erosion management in the tropics. Attempting to increase the cover component of the Universal Soil Loss Equation, in effect, and improving establishment. It worked! But the use of residues also improved the soil carbon levels, in the medium and longer term. That improves soil quality.

With residue left in the field rather than removed, soil carbon levels were 0.2pc higher, soil pH was 5.1 under residue and 4.6 without, and that corn yields on a field sown into residue were 2.7t per hectare compared to 1.5t/ha in a bare field. This data is based on studies of crop residues in a Nigerian corn system. Soil quality is significantly influenced by residue retention. There are also additional studies from both temperate and tropical areas that draw the same conclusions.

Dr Lal has also extrapolated how improving soil carbon might affect food security for the 854 million people currently considered "food insecure". In 2000, the global food deficit was considered to be 13 million tonnes; by 2010, this will have risen to 22 mt, mostly in sub-Saharan Africa. By increasing soil carbon levels in the 532 million hectares of agricultural soils in developing countries by a modest one tonne per hectare per year, Dr Lal calculated an extra 30-50mt of food could be produced per year.

This is a potent message and adds to increasing pressure to better use the millions of kilograms disposed of as recycled organic material in Australia each year. While there are some logistical issues in returning this material to rural areas for use, they need adressing to ensure the material is used effectively.

Soil carbon is vital.......ensure there is more of it!

Soil Erosion a Threat to Food Production in China

Soil erosion in Australia is a serious issue. The environmental brigade will tell you how dire it is, any where and every where. That is an gross over the top attention grabber, for erosion is a natural process closely associated with geological processes over countless millenia. What we need is a system to minimise that soil loss particularly in the most productive land around Australia, or anywhere else in the world too.

Many will argue that the National Landcare program and the myriad action programs at all levels, now operational for about 25 years, has made significant gains in managing the Australian landscape processes, and reducing erosion. At least we like to think so, but it is probably fair to say some good progress continues to be made. The program has been copied and developed in other countries too - notably The Phillipines and South Africa.

While we in Australia might feel good, it is a timely reminder to consider recent information emerging from China. Things are pretty grim in relation to erosion. Picture the giant erosional gullies of the loess plateau......most people have seen those. But it gets worse.

Over a third of China's land is being scoured by serious erosion that is putting its crops and water supply at risk, a three-year nationwide survey has found.

Soil is being washed and blown away not only in remote rural areas, but near mines, factories and even in cities, the official Xinhua agency cited the country's bio-environment security research team saying.

Each year some 4.5 billion tonnes of soil are lost, threatening the country's ability to feed itself.

If the loss continues at this rate, harvests in China's northeastern breadbasket could fall 40 percent in 50 years, adding to erosion costs estimated at 200 billion yuan ($29 billion) in this decade alone.
"China has a more dire situation than India, Japan, the United States, Australia and many other countries suffering from soil erosion," Xinhua quoted the research team saying.

Beijing has long been worried about the desertification of its northern grasslands, and scaled back logging after rain rushing down denuded mountainsides caused massive flooding along the Yangtze in the late 1990s. But around 1.6 million square km of land are still being degraded by water erosion, with almost every river basin affected. The photo shows erosion and bare soils on the loess plateau in China's North East.




Another 2.0 million square km are under attack from wind, the report said.

The survey was the largest on soil conservation since the Communist Party took control of China in 1949.

If you have been to Beijing, you will certainly have experienced the yellow skies from the soil blowing from the west, that irritates the eyes, common in the late winter and early spring periods. Or the steady soil clouds lifted from bare soils in Outer Mongolia, not even that far from Beijing itself. We most certainly could not get farmers to change their thinking and even consider conservation tillage in projects we worked on in China during the late 1990s.

The following two photos show some of the awesome erosion seen on the loess plateau of China. It can be staggering!


A China with food production problems is worth pondering. Also adds some pondering to be considered along with the analysis on "The Politics of Hunger" in a recent post.

[lower two photos used with permission. Thanks. Copyright- Cathy Dowd]