Archive for the ‘Environment’ Category

Wisconsin study shows decisions on pasture use and feed management affect GHG emissions

American researchers have created a study to compare the effects of feeding strategies and the associated crop hectares on the greenhouse  gas emissions from certified organic dairy farms in Wisconsin.

According to a Science Daily report on the work (HERE) consumer demand for organic milk in the US recently surpassed the available supply. Sales of organic products reached US$35 billion in 2014 and continue to rise.

As farms convert  to organic production to meet demand, feeding strategies will need to be adapted to meet USDA National Organic Programme requirements.

Agriculture accounts for around 9% of total US greenhouse gas (GHG) emissions.

The US dairy industry has committed to a 25% reduction of GHG by 2020 relative to 2009. By varying diet formulation and the associated crop production to supply the diet, farmers can affect the quantity of GHG emissions of various feeding systems.

The study to compare the effects of feeding strategies and the associated crop hectares on GHG emissions of certified organic dairy farms was developed by researchers from the University of Wisconsin-Madison.

“Herd feeding strategies and grazing practices influence on-farm GHG emissions not only through crop production, but also by substantially changing the productivity of the herd,” lead author Di Liang said.

“Managing more land as pasture, and obtaining more of the herd feed requirements from pasture, can increase the GHG emissions if pasture and feed management are not optimised to maintain milk production potential.”

The authors identified four feeding strategies that typified those used on farms in Wisconsin, with varying degrees of grazing, land allocated for grazing, and diet supplementation. A 16-year study was used for robust estimates of the yield potential on organically managed crop land in southern Wisconsin as well as nitrous oxide and methane emissions and soil carbon.

Production of organic corn resulted in the greatest nitrous oxide emissions and represented about 8% of total GHG emission;. Corn also had the highest carbon dioxide emissions per hectare.

Emissions decreased as the proportion of soybeans in the diet increased, because soybeans require less nitrogen fertilization than corn grain.

More intensive grazing practices led to higher GHG emission per metric tonne. But  allowing cows more time on pasture resulted in lower emissions associated with cropland. Manure management and replacement heifers accounted for 26.3% and 20.1% of GHG emissions.

Based on their findings, the authors determined that a holistic approach to farm production is necessary. Organic dairy farms with well-managed grazing practices and adequate levels of concentrate in diet can both increase farm profitability and reduce GHG emission per kilogram of milk.

“Consumers often equate more dependence on pasture with environmentally friendly farming, but this study demonstrated that low milk production per cow is a major factor associated with high GHG emission,” said Journal of Dairy Science Editor-in-Chief Matt Lucy.

“Managing both pasture and supplementation to increase milk production per cow will substantially reduce GHG emissions.”

Factors such as dairy cow breed and non-production variables may also have an effect on GHG emissions on organic dairy farms. Thus, future studies are needed in this area to elucidate the effects of grazing management and feeding systems.

With more research, however, crop and milk production, GHG emissions, and farm profitability can be optimised on organic dairy farms.

 

DOC critic says loss of science quality in NZ is having dire consequences

The scientific justifications for the use of 1080 poison have been challenged in an article posted online (HERE) by Dr Jo Pollard, whose CV includes 18 years conducting research on animal management with AgResearch.

Back in the 1990s, she recalls, any hint of a prejudicial bias seriously undermined a scientist’s credibility but nowadays (she says) it seemed a scientist’s selling ability mattered most.

She contends:

“Gaining funding and successfully delivering results that generate more funding is vital to career development. And since the NZ government controls the money (grants to universities, NGOs and its own departments) the government gets and selects what it wants.”

The Government wants and since the 1960s has been getting widespread aerial poisoning with 1080, Dr Pollard says.

“The government has argued it needs to kill introduced mammals claimed to spread bovine tuberculosis (Tb) and threaten native wildlife, and widespread poisoning is the best way.

“Respected scientists are expected to sit tight while the media, government departments and high ranking officials misuse data to suit pre-ordained agendas.”

One example cited by Dr Pollard is the claim by the Parliamentary Commissioner for the Environment, Dr Jan Wright, that 1080 poison is “moderately humane”.

But her focus is on the kea, which she claims is a victim of “New Zealand’s degraded science culture” which

“…has spawned the rise of some disease-busting and biodiversity-conserving specialists whose claims go unchallenged, have a very strong following and who are supporting ever-increasing poisoning campaigns”.

Dr Pollard challenges claims that 1080 is needed to kill stoats.

She refers readers to http://1080science.co.nz/scientific-reviews-of-1080/

The use of 1080 by DOC was the subject of Dr Pollard’s criticism in 2011 HERE and HERE

The DOC response (HERE) was written by Paul Livingstone, manager of TB eradication and research at the Animal Health Board, and Mike Slater, Conservator for DOC on the West Coast.

They said:

Although birds, invertebrates and other animals are certainly not immune to the poison, the risks are greatly mitigated by the lethal doses they need to consume. There is no evidence that the toxin has a cumulative effect, or persists in the food chain. In fact, one of the most remarkable properties of the toxin is how quickly a sub-lethal dose is metabolised and expelled from the body. The risks to non-target species are further alleviated by the extremely strict regulations around how the toxin is used. For example, decades of extensive research and operational experience have enabled us to improve the efficiency and minimise the risks of aerial 1080 operations through:

• A reduction in the average quantity of poison bait used per hectare from 30kg/ha in the 1970s to just 2kg/ha today
• Research into more efficient dispersal methods, such as cluster sowing, that may further reduce the quantity of bait used by up to 75 per cent
• The use of GPS technology to make the deployment of baits accurate to within a couple of metres
• The routine use of cinnamon lure to attract possums and repel birds
• The routine use of carefully-screened cereal baits

The response also noted the Environmental Risk Management Authority, in a reassessment of 1080, had concluded the benefits of using 1080 to control introduced species that are destroying our endemic wildlife and spreading bovine TB outweigh the adverse effects.

Dr Pollard is qualified at Honours level in ecology (Limnology, Ecology and Applied Ecology) and animal behaviour and has particular interests in animal welfare, NZ’s ecology, and scientific integrity.

Another rejoinder from DOC seems inevitable.

Scientific research the key to balancing farm productivity and the environment

We can have economic growth and an improved environment, AgResearch chief executive TOM RICHARDSON argues in this article in NZ Farmer (see HERE)…

Chances are you have read about it in your newspapers, in your online news feeds, heard about it on radio or television, or discussed it with family or friends. Wherever you go, the issue of farming in New Zealand and its impact on the environment is a hot topic.

There has been a huge amount of debate from all quarters about what the real and measurable impact of farming practices are, who is to blame, what is being done to mitigate it, and what more can be done.

Recently a piece on TVNZ’s Sunday programme on dairy farming provoked a host of strong responses about the perception and realities of the dairy industry. A report released recently by the Prime Minister’s Chief Science Advisor Sir Peter Gluckman on the state of New Zealand’s fresh waters provided important insights into the challenges that exist, while a newly published review by the OECD (Organisation for Economic Cooperation and Development) on New Zealand’s environmental performance has added to the debate about the pressures we face.

Agriculture remains the backbone of New Zealand’s economy, and there is still plenty of scope for growth in the value of the agricultural products that we sell to the world. In fact, New Zealand’s forecast economic growth over the coming decades hinges on growing the value of agricultural exports. And this must be done whilst enhancing the environments we farm in.

So we must confront these seemingly conflicting challenges if we – and future generations – are to enjoy the quality of life and opportunities afforded by economic prosperity, and the enjoyment of our natural environments which we hold so dear.

As the head of a science organisation which is focused on solving that conundrum I see our role in this being clear, and critically important. Science needs to lead the way by finding solutions to these seemingly intractable problems, and in partnership with central and local governments, agri-businesses, sector organisations, and farmers we need to ensure these solutions find their way into practice on New Zealand’s farms.

By investing in science now we are investing in the future of our economy and the enhancement of our environment that sets New Zealand, and our high value export products, apart from the pack.

We can’t create more land and we can’t continue the generations of focus on more inputs – such as animals, water and fertiliser – to drive more production. We must get smarter.

We can produce better pastures, better livestock, and better farm systems that will enable both profitable farming and enhanced environments. That is what drives our dedicated scientists to tackle big issues such as our agricultural greenhouse gas emissions and managing the nutrient losses from farms that can impact on soils and waterways.

A big part of this is scientists working alongside farmers to see what makes a real difference when it comes to environmental impacts.

As one example drawn from our work across the country, the work of AgResearch and our partners alongside South Canterbury farmers Bill and Shirley Wright has shown us how, over time (in this case almost 25 years), a farm can significantly reduce the intensity of its greenhouse gas emissions while continuing to grow its profitability and productivity. We have also learned from this working farm example what approaches can have an impact on the loss of nutrients on the farm without compromising the bottom line.

As we look further to the future, science is giving us insights into new options to solve this conundrum. With methane being the largest contributor to New Zealand’s greenhouse gas emissions, AgResearch scientists are leading the international effort to develop approaches to reduce methane emissions from livestock, through animal breeding, changing the composition of what the animals eat, and potentially a methane limiting vaccine that is currently in testing.

New Zealand’s agricultural exports are based on pastures, and here too new options are emerging from our laboratories.  AgResearch scientists have produced a ryegrass using new genetic technologies that laboratory trials suggest has a 50 per cent higher growth rate, and significantly higher energy content for growth of the animals eating it, with less nitrogen excreted that can make its way into rivers and streams and affect the water quality. Laboratory testing has also shown it to be more drought resistant, and the potential to reduce methane production in animals by 15-23 per cent.

This new generation ryegrass is now being field tested in the United States to determine if those observations hold true in the field. If they do, it is a potential game changer for New Zealand. Of course the debate around genetic modification would fill a whole column on its own – and I won’t attempt to go into that here – but this grass does give an insight into the possibilities that are coming from science here at AgResearch and around the world.

These are just a couple of examples, but the most exciting thing about science is that we are always coming across new possibilities that we can seize upon.  I am confident that with the right investment and commitment, we can solve New Zealand’s biggest conundrum and enjoy that quality of life we all seek.

 – Stuff

Scientists will march for science tomorrow (regardless of whether Trump takes notice)

Marches for Science will take place in New Zealand and around the world tomorrow to mark Earth Day, which is celebrated every year on April 22 with festivals, parades and rallies in almost 200 countries to demonstrate support for environmental protection.

The organisers of the marches in New Zealand have written about their aims here and here.

Events in almost 200 countries are coordinated by the Earth Day Network, a Washington-based organisation with a mission “to diversify, educate and activate the environmental movement worldwide”.

More than 1 billion people now participate in Earth Day activities each year.

The very first event for Earth Day, which was held in America nearly five decades ago following a devastating oil spill, is credited as the beginning of the modern environmental movement.

Since its launch, Earth Day has been supported by an array of famous faces, including Hollywood stars Leonardo DiCaprio and Emma Watson.

On Earth Day last year, the landmark Paris Agreement was signed by the United States, China and some 120 other countries.

This year the specific focus is on creating better environmental and climate literacy and educating people – both children and adults – on environmental issues.

Association of Scientists president, Dr Craig Stevens, told Mike Hosking protesters will also express their opposition to President Trump’s fundamental position against climate change.

“This march is an opportunity to show where the public of the world stand on science.”

But the marches have a much broader objective, he said.

“It’s also a celebration of science in New Zealand and showing that there’s a critical mass amongst the public of people who really value science.”

In Marlborough, National MP Stuart Smith, Green Party MP Kennedy Graham and Labour Party candidate Janette Walker will be at the province’s inaugural Earth Day Party. 

Each will be given a minute to outline their thoughts on a carbon-neutral future to the public before answering questions.

Victoria University geology professor emeritus Peter Barrett will also attend the event at Marlborough’s A&P Park where he will give a talk on global warming.

The Royal Society of New Zealand has provided information on other events:

Auckland | 1.30pm start at Queen Elizabeth Square

Palmerston North | 11am The Square, Palmerston North Central

Christchurch | 10am start at the Canterbury Museum

Wellington | 10am start at Civic Square

Queenstown | Details to be confirmed

Dunedin | 11am at Otago Museum Reserve

Details for all marches are also available on the March for Science NZ Facebook Page

The New Zealand Science Media Centre provides more information – Preparing to March for Science – In the News.

Endangered beetle faces ‘unholy alliance’ of rabbits and redbacks

An “unholy alliance” between rabbits and Australian redback spiders is threatening the existence of an endangered New Zealand species, a study led by AgResearch has shown.

Carried out with the Department of Conservation (DOC) and University of Otago, the study has illustrated the struggle for the ongoing survival of the Cromwell chafer beetle – a nationally endangered native species that can now be found only in the 81 hectare Cromwell Chafer Beetle Nature Reserve between Cromwell and Bannockburn, in Central Otago.

The study found numerous rabbit holes that provided shelter for the rabbits were also proving ideal spaces for the redback spiders to establish their webs. Investigation of those webs in the rabbit holes found the Cromwell chafer beetle was the second-most commonly found prey of the spiders.

These findings “give a fascinating insight into the almost accidental relationships that can develop between species in the natural world, and how that can impact on other species,” says AgResearch Principal Scientist Dr Barbara Barratt.

As a result of the research, DOC has carried out a programme to break down old rabbit holes and hummocks in the reserve to destroy spider nests, and does regular rabbit control. An annual survey for beetle larvae with AgResearch will show whether these actions are having an effect.

Beetle larvae will be surveyed next summer to see what effect reducing redback spider nests is having on the Cromwell chafer beetle.

The Cromwell chafer beetle (Prodontria lewisi) is a large flightless beetle that lives underground in the sandy soils of the Cromwell river terrace. In spring and summer adult beetles emerge from the ground at night to feed on plants and to breed.

Trump is poised to begin rolling back Obama’s environmental regulations

President Trump is expected to sign an executive order today (NZ time) aimed at rolling back one of former President Barack Obama’s major environmental regulations to protect American waterways. But according to the New York Times (HERE), it will have almost no immediate legal effect.

The order essentially will enable Mr Trump to direct his new Environmental Protection Agency administrator, Scott Pruitt, to begin the complicated legal process of rewriting the sweeping 2015 rule known as Waters of the United States. But that effort could take longer than a single presidential term, legal experts are quoted as saying.

The order is the first of two announcements expected to direct Mr Pruitt to begin dismantling the major pillars of Mr Obama’s environmental legacy.

In the coming week, Mr. Trump is expected to sign a similar order instructing Mr Pruitt to begin the process of withdrawing and revising Mr Obama’s signature 2015 climate-change regulation, aimed at curbing emissions of planet-warming greenhouse gases from coal-fired power plants.

Both of those rules were finalised under existing laws long before Mr Obama left office. Legal experts say they cannot therefore be simply undone with a stroke of the president’s pen.

The clean water rule was issued under the 1972 Clean Water Act. It gives the federal government broad authority to limit pollution in major bodies of water, like Chesapeake Bay, the Mississippi River and Puget Sound, as well as in streams and wetlands that drain into those larger waters.

The water rule came under fierce attack from farmers, property developers, fertiliser and pesticide makers, oil and gas producers, golf-course owners and other business interests that contend it will stifle economic growth and intrude on property owners’ rights.

The American Farm Bureau Federation, which has led the legal fight against the rule, contends that it places an undue burden on farmers in particular, who may find themselves required to apply for federal permits to use fertiliser near ditches and streams on their property that may eventually flow into larger rivers.

Grasslands are shown to hold potential for increased meat and dairy production

About 40% of natural grasslands worldwide have the potential to support increased livestock grazing, according to a new study published in the journal Global Change Biology. 

This translates to a potential increase of 5% in milk production and 4% in meat production compared to the year 2000 or allow for  2.8 million square kilometers of grassland area to be released from production.

The research findings are reported (here) by Science Daily, which notes that global food production must be increased to feed the world’s growing population, but food production systems have impacts on the environment and climate.

Livestock products, including meat and milk, are a major food source for millions of people. Demand for these products is increasing but livestock and conversion of land for increased livestock production can lead to increased greenhouse gas emissions or soil erosion through overgrazing.

“Grasslands are generally regarded to play an important role in increasing food production to meet future food demand,” says Tamara Fetzel, a researcher at the Institute of Social Ecology in Vienna (Alpen Adria University), who led the study as part of her participation in the 2015 Young Scientists Summer Program at IIASA.

“But to achieve this target in a sustainable manner, our study suggests that we should focus on making more efficient use of currently available land resources, instead of converting land from other uses.”

How much livestock grasslands can support depends on a number of variables including climatic, biological, and socio-economic factors such as management, storage systems, and biomass conservation.

In the new study, the researchers explored the impact of seasonal patterns of biomass supply on the potential dynamics of grass-based livestock systems, at a global scale. Fetzel and colleagues identified areas where additional biomass could potentially be extracted from the landscape, by comparing the current level of grazing intensity to the maximum levels supported in periods of minimum biomass supply, such as winter or dry periods.

The authors also discuss many socioeconomic and ecological constraints related to unlocking this potential, such as a lack of infrastructure, market access, knowledge, finance, and labor constraints or the impacts of droughts, and potential negative trade-offs  such as loss of biodiversity or soil degradation.

“Grassland productivity and intensification potential are some of the most uncertain parameters in global land-use assessments and are often used to estimate ambitious GHG mitigation targets, “says IIASA researcher Petr Havlík, a study coauthor who advised Tamara Fetzel during the YSSP together with Karl-Heinz Erb from the Institute of Social Ecology Vienna.

“Making estimates of potential maximum grazing intensity more realistic by considering seasonal constraints reveals a certain potential to increase grazing intensity in some places, yet shows that the actual grassland area available for other purposes remains limited,”

Fetzel T, Havlik P, Herrero M, Erb K-H (2017). Seasonality constraints to livestock grazing intensity. Global Change Biology, http://onlinelibrary.wiley.com/wol1/doi/10.1111/gcb.13591/full.