Environment improving but some scientists reluctant to admit it

Comment by Mick Keogh

Australian land managers have dramatically improved the state of the environment over the past decade, with native vegetation clearing rates dropping to almost zero, farms being replanted with trees, native plants and animal populations reinvigorated, pest animal populations controlled, water and wind erosion significantly reduced through better management practices, and the agriculture sector leading the way in developing projects to mitigate greenhouse emissions.  However, while all these improvements are noted in the State of the Environment report released in March 2017, the authors persisted in painting a gloomy picture of the future.

The State of the Environment report was established by the Australian Government in 1996 as a five yearly report card on trends in environmental indicators. The aim was to establish an objective process of environmental assessment, in order to provide a stronger evidence base for policies or programs that governments might seek to implement. In some respects it was designed as an attempt to get away from ‘crisis-driven’ reactionary environmental policy, whereby policies and programs were often knee-jerk responses to issues that were highlighted in campaigns by environmental groups – often in concert with scientists (some of whom may also have benefited through increased funding!).

The classic example of this ‘crisis’-driven environmental policy were the national dryland salinity programs. These were initiated on the basis of the dryland salinity audit of 2000, which projected that the area of land severely at risk of being affected by dryland salinity would increase from around 5.7 million hectares to 17 million hectares by 2050. These numbers resulted in blazing headlines about agriculture disappearing in a sea of salt, along with regional towns and even cities.

Unfortunately, little attention was paid to the extremely questionable methodology used to derive these numbers, despite criticism by legitimate soil scientists. It is interesting to note that, despite the proclaimed danger to the future of agriculture of the issue, the audit of areas affected by dryland salinity has never been repeated, figure 1. There are occasionally grudging references to the fact that the original estimates might have been overcooked  – for example the recent released State of the Environment report notes

” Increases in dryland salinity appear to have been slowed by the millennium drought, although a return to wetter conditions is likely to increase spread of dryland salinity.”

This comment is somewhat curious, given that there has been no assessment of the extent of dryland salinity since the initial assessment in 2000 (so what is the basis for the ‘slowed’ comment?), and the main thrust of the rest of the report is that climate change is likely to result in a hotter and drier environment in the future, not a wetter environment.

Figure 1: The report give no recognition to the enormous progress being made in developing farming systems which prevent dryland salinity spreading. Photo: Patrick Francis.

The 2016 State of the Environment report actually provided a very positive picture of changes that have occurred over recent years, although it is fair to say that the authors were less than exuberant in their praise of the changes. The summary of the main findings for the land sector was as follows:

Pressures affecting the land environment

“Although a changing climate has shaped the Australian landscape and its vegetation, the current rate of climate change is likely to result in changes in the distribution and composition of vegetation communities. Some communities are likely to disappear, and others will be transformed as different species mix together to form novel communities, in some of which exotic species are likely to play a significant role. Many agricultural and forestry systems are likely to be adversely affected.

 

Rates of land clearing, although decreasing in many states, are still increasing in some states in response to relaxation of legislative controls. There is recognition that land clearing can affect environmental services, such as control of erosion and maintenance of soil quality, and that habitat fragmentation, which is a typical consequence of land clearing, places increased pressures on the survival of remnant patches of natural vegetation.

 

Widespread landscape-scale pressures (including invasive species and changed bushfire regimes) continue to threaten land managed for environmental values, conservation and extensive agriculture. Bushfire frequencies are increasing, as are the number of invasive species that are threatening Australian landscapes and industries. Increasing resistance of invasive weeds to herbicides is recognised as a growing problem.

 

Pressures on the land environment associated with grazing—Australia’s most extensive land use—have decreased somewhat, with a decrease in the size of the national cattle herd and in the area grazed.

 

Although better management of many agricultural systems has reduced their impacts on the land environment, a number of issues relating to nutrient and soil management remain. Low-tillage conservation agriculture approaches have been successful, but uptake appears to be declining in some areas. Management of native and plantation forestry faces challenges as the industry ceases to expand, and the delivery of long-term management agreements falls short of expectations.

 

State and trends of the land environment

The area of land managed for conservation has continued to expand, in both private and public sectors. This is partly due to a decrease in the area of native forest managed for production of timber and wood products. The area formally owned and managed by Indigenous Australians has also continued to increase, although the majority of such areas are in very remote parts of the continent.

 

There is increasing investment in use of land and native vegetation for carbon sequestration, carbon emissions avoidance or emissions reductions through appropriate management. In some cases, management for carbon outcomes may be at odds with management for biodiversity outcomes.

 

Land management practices are improving, particularly in relation to soil management, and reduction of nutrient and pesticide run-off. Some of this is attributable to improved integrated pest management programs, which reduce the required application of pesticides. Current rates of soil erosion by water across much of Australia exceed soil formation rates, although progress has been made in reducing soil erosion through adoption of soil conservation measures.

 

A new generation of large-scale soil mapping will inform national mapping and monitoring of carbon, biodiversity, agricultural impact and ecosystem functions in general. Increases in dryland salinity appear to have been slowed by the millennium drought, although a return to wetter conditions is likely to increase spread of dryland salinity. Management of soil carbon is central to maintaining soil health and ensuring global food security, as well as providing an important sink for atmospheric carbon; Australia currently has a lower soil organic carbon stock than other parts of the world. Soil acidification is another challenge facing agriculture, with annual lime application currently lower than required to combat the problem in some jurisdictions.

 

Impacts of human land use are spread unevenly across the country. Nearly 90 per cent of Australia’s native vegetation remains in some form. Vegetation clearing is concentrated in the long-settled agricultural and coastal zones, where more than 50 per cent of native vegetation has typically been cleared. Vegetation condition usually declines along with extent, because increased fragmentation increases the impacts of invasive species and bushfires, and decreases ecosystem functions such as pollination and seed dispersal.”

The issues noted above, ranging from increases in land reserved for conservation to improvements in land management and the development of agriculture-based carbon sequestration projects would normally attract very positive commentary, but this was overshadowed by negative commentary about potential future threats, and what seems to be a very “glass half empty” view of changes that have occurred, figure 2.

Figure 2: Many farmers are recorded as making significant contributions to ecosystem functions on farms but most of it goes unrecognized in the State of the Environment report. Photo: Patrick Francis.

The following passage from the report is an example:

“During the past 5 years, native vegetation has continued to be cleared, bushfire frequencies have increased, and the number of invasive species has also increased. Many agricultural practices have improved, reducing impacts on the environment, but there is room for further improvement. Urban expansion continues, but a slowing in the number of new mining developments has reduced alienation of agricultural land by the resources sector. The area of the conservation estate has increased, as has the area managed by Indigenous Australian”.

On the issue of land clearing, despite the rates of clearing on previously uncleared land declining to minimal levels, figure 3, the report instead focused on rates of clearing of regrowth, stating that such clearing damages the future resilience of the environment. This despite the fact that clearing of regrowth (referred to as invasive native scrub) is actually encouraged in some regions and is recognised as resulting beneficial environmental outcomes.

Figure 3: First-time forest conversion and reclearing in Australia, 1990–2014. Source: State of Environment Report.

The carping criticism also ignores the amount of voluntary re-vegetation that has been implemented on farmland and which does not appear in any official statistics, but which has transformed landscapes which previously only had very limited tree coverage. On many farms, extensive tree planting has occurred over the past decade, and native bird and animal populations are now increasing, but no one would be any the wiser about this from reading the State of the Environment report.
The negativity evident in this most recent report has a number of long-term implications. First, it reduces the credibility of what is otherwise a sensible and logical process, and hence the resources used to develop the report are depreciated in terms of their potential impact. Second, it sends a strong message to Australian land managers that no amount of environmental restoration will ever satisfy scientists and environmentalists, therefore their messages should be ignored.

Source: Mick Keogh, is executive director, Australian Farm Institute, www.farminstitute.org.au