Cli­mate

Farm­ing car­bon

Farms & Farm Machinery - - Contents - writes CSIRO sci­en­tist Brett An­thony Bryan

Aus­tralia’s agri­cul­tural lands help to feed about 60 mil­lion peo­ple world­wide, and also sup­port tens of thou­sands of farm­ers as well as ru­ral com­mu­ni­ties and in­dus­tries.

But a grow­ing global pop­u­la­tion with a grow­ing ap­petite is plac­ing in­creas­ing de­mands on our agri­cul­tural land. At the same time, the cli­mate is warm­ing and in many places get­ting drier too.

Agri­cul­ture, and par­tic­u­larly live­stock, is cur­rently a ma­jor con­trib­u­tor to green­house gas emis­sions. But new mar­kets and in­cen­tives could make stor­ing car­bon or pro­duc­ing en­ergy from land more prof­itable than farm­ing, and turn our agri­cul­tural land into a car­bon sink.

How might these com­pet­ing forces play out in chang­ing Aus­tralian land use? Our re­search, pub­lished in Global En­vi­ron­men­tal Change, as­sesses a range of po­ten­tial path­ways for Aus­tralia’s agri­cul­tural land as part of CSIRO’s Na­tional Out­look.

CHANG­ING LAND­SCAPES

The only con­stant in land­scapes is change. Ecosys­tems are al­ways chang­ing in re­sponse to nat­u­ral driv­ers such as fire and flood.

Hu­mans have com­pli­cated things. In­dige­nous Aus­tralians ma­nip­u­lated the Aus­tralian land­scape and cli­mate through burn­ing for mil­len­nia, sus­tain­ing a pop­u­la­tion of around 750,000 and un­der­pin­ning a cul­ture.

European coloni­sa­tion brought a dif­fer­ent and more per­va­sive change, clear­ing land, build­ing cities, damming rivers and es­tab­lish­ing an in­creas­ingly mech­a­nised and in­dus­tri­alised agri­cul­ture.

These iconic but changed land­scapes in­spired the ro­man­tic art of Arthur Streeton and po­etry of Banjo Pater­son among many oth­ers — and helped forge a young na­tion’s iden­tity.

Change can hap­pen sur­pris­ingly quickly. Of­ten be­fore we know it we’ve gone too far and need to scram­ble for fixes that are so of­ten costly, slow and ul­ti­mately in­ad­e­quate.

For ex­am­ple, in South Aus­tralia, re­searchers in the early 1960s raised the alarm that the fever­ish post-war pe­riod of soldier re­set­tle­ment, land clear­ance and agri­cul­tural devel­op­ment threat­ened en­tire na­tive plant and an­i­mal com­mu­ni­ties with ex­tinc­tion. The gov­ern­ment’s re­sponse over the fol­low­ing 30 years was to ex­pand greatly the con­ser­va­tion re­serve net­work and even­tu­ally pro­hibit land clear­ing.

HIS­TORY RE­PEAT­ING?

Agri­cul­tural lands pro­duce a range of goods and ser­vices. But in many places the fo­cus on agri­cul­tural pro­duc­tiv­ity has come at the ex­pense of ecosys­tems. Bio­di­ver­sity, soil and wa­ter are all on down­ward trends.

Is the bal­ance right? Opin­ion varies. Many would say no, and con­sider the sta­tus quo to be stacked strongly against the en­vi­ron­ment.

Oth­ers see agri­cul­ture as en­ter­ing a boom time, driven by grow­ing pop­u­la­tion and ris­ing food prices. Sub­stan­tial in­ter­est from over­seas in­vestors in Aus­tralian agri­cul­tural land re­flects this op­por­tu­nity.

Parts of Aus­tralia’s agri­cul­tural land con­tinue to change fast. Les­sons hard-learned by South Aus­tralia seem to have been for­got­ten. Rates of land clear­ance in Queens­land are ris­ing again since 2010 af­ter a longterm trend of de­cline. (See map.)

In the 1990s, new fi­nan­cial in­cen­tives led to the plant­ing of over 1 mil­lion hectares of for­est in south­ern Aus­tralia. Now a failed busi­ness model, many of these plan­ta­tions are be­ing re­turned to agri­cul­ture.

De­mand for more se­cure sources of en­ergy has gen­er­ated rapid ex­pan­sion of coal seam gas and wind power gen­er­a­tion, and the devel­op­ment of north­ern Aus­tralia re­mains a bi­par­ti­san pri­or­ity.

“Who knows? A pay rise while watch­ing trees grow could be an at­trac­tive propo­si­tion for our age­ing farm­ers”

World­wide, Aus­tralia is not alone — many in­ter­na­tional ex­am­ples also ex­ist of re­cent, mas­sive, rapid and ac­cel­er­at­ing changes in how land is used.

Aus­tralia has his­tor­i­cally taken a hands-off ap­proach to man­ag­ing land use change, in­stead fo­cus­ing on in­creas­ing the pro­duc­tiv­ity and com­pet­i­tive­ness of agri­cul­ture. Apart from a hand­ful of plan­ning and en­vi­ron­men­tal reg­u­la­tions, the use of land has been sub­ject to min­i­mal gov­er­nance or strate­gic di­rec­tion.

WHERE TO FROM HERE?

What is it that Aus­tralians re­ally want from our land? We know what we don’t want: wall-to-wall crops, pas­ture, build­ings, gas wells, mines, wind farms or trees.

We can ex­pect healthy de­bate around the mar­gins, but, in gen­eral, di­ver­sity, pro­duc­tiv­ity and sus­tain­abil­ity seem to be widely val­ued. Most of us want to leave the place in de­cent con­di­tion for fu­ture gen­er­a­tions.

Europe has had this con­ver­sa­tion and knows what it wants from its land­scapes – and it’s not afraid to pay for it (for in­stance, through agri­cul­tural sub­si­dies). A deep aes­thetic and cul­tural her­itage is the cen­tral ob­jec­tive, with a bal­ance of re­cre­ation op­por­tu­ni­ties, tourism, a clean and healthy en­vi­ron­ment and high­qual­ity pro­duce all be­ing high pri­or­i­ties.

Once we know what we want, we can work out how to get there. That’s where science can help. We now have the abil­ity to pro­ject changes in land use in re­sponse to pol­icy and global change, and the en­vi­ron­men­tal and eco­nomic con­se­quences.

CSIRO’s re­cent Na­tional Out­look mapped Aus­tralia’s po­ten­tial fu­ture path­ways. A com­pan­ion pa­per in Na­ture mag­a­zine found that it is pos­si­ble to achieve strong eco­nomic growth and re­duce en­vi­ron­men­tal pres­sure, if we put the right poli­cies in place now. It pro­vides a glimpse of how our ru­ral lands might re­spond to co­a­lesc­ing fu­ture change pres­sures.

PAY RISE FROM CAR­BON?

In our mod­el­ling, car­bon se­ques­tra­tion in the land sec­tor plays a key role of Aus­tralia’s fu­ture. Land sys­tems can help with the heavy lift­ing re­quired to hold global warm­ing to 2C as re­cently agreed in Paris.

There are sev­eral fac­tors that could drive this change, in­clud­ing cli­mate, car­bon pric­ing, global food de­mand, and en­ergy prices.

We mod­elled the eco­nomic po­ten­tial for land use change and its im­pacts in over 600 sce­nar­ios (full data is avail­able at http://bit.ly/TradeFar­mCSIRO), com­bin­ing a suite of global out­looks and na­tional pol­icy op­tions. A car­bon price, which en­ables land­hold­ers to make money from stor­ing car­bon in trees and soils (of­ten much more money than from farm­ing), may in­crease pres­sure to shift farm­land to re­stored forests.

Who knows? A pay rise while watch­ing trees grow could be an at­trac­tive propo­si­tion for our age­ing farm­ers. Com­ple­men­tary bio­di­ver­sity pay­ments could also help ar­rest de­clines in wildlife and help it adapt to cli­mate change.

If we re­dou­ble our fo­cus on pro­duc­tiv­ity, by 2050 agri­cul­ture will pro­duce more than today, even as farm­land con­tracts. The least pro­duc­tive ar­eas are less able to com­pete with re­for­esta­tion and other new land uses, leav­ing the most ef­fi­cient agri­cul­tural land in pro­duc­tion. But trade-offs are likely. Trees use a lot more wa­ter than crops and pas­ture, so we will need to think care­fully about man­ag­ing wa­ter re­sources.

Aus­tralians care about their land and are more aware than ever about what is hap­pen­ing to it. While we can have some con­trol over the fu­ture of our land, and we do ex­er­cise this con­trol in cer­tain cir­cum­stances (such as ur­ban plan­ning), our longterm ap­proach to ru­ral land has been to let en­vi­ron­men­tal and eco­nomic forces play out and let the in­vis­i­ble hand of eco­nomics de­ter­mine what will be.

Given the pace at which change can hap­pen, a smarter ap­proach will be to start the con­ver­sa­tion, work out what it is we want from our land, and put the poli­cies and in­sti­tu­tions in place to get us there.

‘Still glides the stream, and shall for ever glide’, 1890. Arthur Streeton. The Art Gallery of NSW de­scribes the paint­ing as ‘an ide­alised vi­sion of the Yarra River at Hei­del­berg, with the Don­caster Tower in the mid­dle dis­tance and the Dan­de­nong Ranges beyond’. This scene is now sub­ur­ban Mel­bourne

Map show­ing the amount of Queens­land habi­tat for threat­ened species cleared be­tween 2012 and 2014. Source: WWF Brett An­thony Bryan is Prin­ci­pal Re­search Sci­en­tist, En­vi­ron­men­tal-Eco­nomic In­te­gra­tion, at the CSIRO. This ar­ti­cle was orig­i­nally pub­lished on the­con­ver­sa­tion.com/au

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