Incorporation of Practical Measures to Assist Conservation of Biodiversity Within Sustainable Beef Production in Northern Australia
Edited by Sue McIntyre, CSIRO Sustainable Ecosystems
Jointly funded by MLA, CSIRO and Environment Australia, October 2001
ISBN 1 74036 189 X
Results and Discussion
Objective: Significantly advance conceptual understanding of the relationships between the grazing of cattle and grazing management, and the conservation of regional biodiversity within the variegated landscapes of the north.
This objective was addressed in two ways:
- We conducted original research on the two case properties in the Crows Nest district, to better understand the effects of grazing, and other management associated with beef cattle production, on native grasslands.
- Existing knowledge on the ecological functioning of grassy woodlands and landscape processes was synthesized. This provided a starting point for communication and for the economic modelling.
The results are discussed in sub-sections below
Pasture productivity, diversity and stability
In eucalypt woodlands, the grassy layer is the primary source of animal feed. It is also where most of the biodiversity is concentrated. We recorded 400 types of grassland plant in two seasons' sampling (McIntyre, Best & Martin, submitted). The insects, spiders and other invertebrates living amongst the grass and soil account for many more species. They are responsible for maintaining plant production through nutrient recycling and soil engineering. The structural condition of the grasslands, in turn, affects the ability of birds, reptiles and mammals to survive. These larger animals depend on plant growth and litter to provide food and tall grass tussocks to provide shelter and nesting sites.
The way grazing affects the biodiversity of grasslands has major implications for plant production, and ultimately, livestock production.
The native pastures in the Crows Nest district were originally dominated by tall tussock grasses (species of Themeda, Cymbopogon, Bothriochloa, Dichanthium, Aristida and Heteropogon) but livestock grazing can cause obvious structural modifications. In these pastures it is possible to identify three patch types in paddocks:
- Tall tussock (dominated by some of the original species listed above);
- Short tussock (dense turf of small tussock species, especially Eremochloa, Chloris, Eragrostis and Bothriochloa);
- Lawn (a short dense turf of rhizomatous and/or stoloniferous species e.g. Cynodon, Digitaria).
The two short patch types vary in size, ranging from a square metre to a hectare. We hypothesized that the short tussock and lawn patches are similar to the short patches associated with heavy grazing and loss of pasture condition as described in a grazing trial in the Burnett region (MLA Project CS195; McIntyre 1996). The change in sward structure is also significant for the diversity of plants and animals that can persist in pastures.
We hypothesized that both short patch types resulted from high grazing pressure and that lawns developed when there were also increases in soil fertility. These were tested in an experiment which measured the response of tall tussock patches to mowing (representing grazing pressure) and fertiliser application (soil fertility) over three years. We transplanted short patch species to all treatments to ensure the possibility of patch transition. Methods and results are presented in Appendix 8, Part A.
The changes in abundance supported our initial hypothesis to some extent - the lightly defoliated plots remained dominated by the tall grasses and stoloniferous grasses were increasing on the heavy defoliation-high fertility plots. However, there was little change in the heavy defoliation-low fertility plots. This probably reflects a lack of seed of the low tussock grasses and slow rates of increase in size of these plants even if they are able to colonise new areas.
The experiment provided information that could not be generated from field observations, for example, fertiliser application reduced species density (richness). In the survey of different habitats in the study area, fertilization was always coupled with cultivation and it was not possible to separate the effects of the two disturbances. The experimental results suggest that applications of fertilizer onto native pastures could present problems for grassland conservation.
Management to alter patch type
Can short tussock or lawn patches be managed to encourage transition to tall tussocks? While short patches can provide areas of high quality grazing, they represent a problem for natural resource conservation if they are too extensive. Local producers have expressed an interest in restoring their pastures to Themeda and other palatable tall grasses. Resting from grazing and the use of fire are possible management tools and their effects were tested in two experiments. Cages were used to exclude grazing and some plots were burnt. Changes in species density and abundance were recorded for four years. Methods and results are presented in Appendix 8, Part B.
Overall, there were only small changes in the pasture composition during the four years of exclosure from grazing, and no responses to burning. In the lawn patches (dominated by Cynodon spp.) and short tussock patches (dominated by Eremochloa) these dominants were maintained where grazing continued, indicating the stability of these patches. When cattle were excluded, the dominants declined; in the short tussock patches, the dominant Eremechloa was replaced by tall grasses. In the lawn patches a variety of types of plant (but not tall grasses) replaced the stoloniferous grasses.
Our interpretation is that there were established, but suppressed tall grasses in the short tussock patches (e.g. Themeda). Once grazing was excluded, existing plants grew larger, but new plants did not establish in significant numbers. In the lawn patches, tall grasses appear to have been completely eliminated and establishment from seed did not occur. Perennial grass seeds do not persist in the soil (unpublished data) so once the adults are eliminated, seed dispersal must be combined with seed establishment to restore perennial grasses. Lawn and short tussock patches (with no tall tussock species present), therefore, represent a very stable state in the sense of conventional state-and-transition models.
Overall, our results confirm the stability of the native pastures under present management. The advantage of this is that these native grasslands are resistant to degradation - a fact reflected in their extremely good condition when assessed in the district (Martin et al. 2000; Appendix 3). A disadvantage is that, once composition is altered by grazing, the pastures are difficult to rehabilitate i.e. their resilience is low. Four years of pasture resting is a long spelling period, especially if changes don't occur.
Our observations of grazed patches and the high resistance, but low resilience, of the pastures is similar to that observed in the Glenwood grazing trial (McIntyre 1996). The Crows Nest observations were made on sandstone and metamorphic substrates, while Glenwood results are for granite. Thus the generality of the results is boosted by considering both studies.
However, the argument for pasture resting is still strong, as many pastures do support tall tussock species that are grazed down and not apparent to the manager. In this case, one or two seasons of resting should be enough to see whether tall tussock species are present. A second season of resting may be needed to enable these species to recover sufficiently to set seed.
Landscape patterns of grassland diversity
Our experimental results have confirmed that while manipulations are necessary to understand dynamics of vegetation, field observations of the landscape are also important to detect the effects of long-term management. Sampling over larger areas than plots is also needed to capture a realistic amount of variation in the vegetation at landscape scales. Our survey of habitats throughout the district (Fig. 2) enabled us to do this.
The aims of this survey were:
- To make a comprehensive record of the understorey species occurring on the Crows Nest case study properties and surrounds.
- To document how the patterns of plant diversity vary according to the environment (e.g. landscape position, soil type) and management variables (e.g. grazing, soil disturbance) that operate in the grassy woodlands.
The methods, results and interpretation of the data are detailed in Appendix 1 [McIntyre (2000), McIntyre, Martin & McIvor (2000), McIntyre & Martin (2001), McIntyre, Best & Martin (submitted), McIntyre & Martin (submitted)]. Key conclusions arising from this study are:
- Low intensity cattle grazing is compatible with maintenance of grassland diversity and function. The grasslands in the district, including the native pastures, were found to be amongst the most species-rich in the world (at the spatial scale measured) and contained many species of conservation significance.
- Although commercial native pastures can support a diversity grassland plants, there are a group of grazing-sensitive species that are restricted to roadsides, reserves and stock routes. These habitats are limited in area and are vulnerable to non-intentional destruction e.g. through roadworks, earthworks, fertilizer run-off and subsequent weed invasion.
- On properties, vulnerable grazing-sensitive species are likely to persist in areas with a light grazing history. As these areas are very restricted in grassy woodlands, they should be given high conservation priority in farm planning, and their development and heavy grazing should be avoided.
- The most significant threat to the native grasslands is further expansion of intensive land uses. Cropping, cultivation and fertilization would pose a major threat to grassland vegetation and would threaten 69 of the 121 native species analysed.
- Exotic pasture grasses are an invasive element of native grasslands. Paspalum dilatatum is invasive of all habitats and becomes dominant with any level of soil disturbance or enrichment. Rhodes grass (Chloris gayana) is absent from native pastures but becomes dominant in disturbed roadsides. When dominant, grasses such as green panic (Panicum maximum) can virtually eliminate other grassland species.
The development of principles and thresholds
In the previous section, we have described recent findings on the relationships between the grasslands, grazing, and other management. However, it is also necessary to consider the impacts of beef property management on the wider range of natural resources in grazed landscapes including soils, trees, water and native animals.
These management impacts should be viewed in terms of landscape scale ecological processes. It is increasingly evident that issues such as dryland salinity, water quality decline, eucalypt dieback and biodiversity losses have arisen through our failure to understand management impacts as they progressively accumulate across the landscape. This is where the concept of thresholds becomes important. Thresholds indicate a point above (or below) which a small change in a management factor will produce a large change in an ecological process. For example, tree clearing may have no observable impact on bird life until so much habitat is cleared, that birds can no longer move around in the landscape to eat, breed and avoid adverse weather conditions. Species then disappear from the landscape. The maximum point of clearing before abrupt changes to the bird community are observed is an example of a threshold.
Figure 2: Part of the survey area in the Crows Nest district showing the habitats that are typical of eucalypt grassy woodland that have been altered to become a variegated landscape as a result of clearing and habitat modification.
From foreground: crops, sown pasture, grazed woodland, native pasture, roadside.
The concept of thresholds, the set of principles and thresholds developed, and their scientific rationale are presented in Appendix 1 (McIntyre, McIvor & MacLeod 2000) and Appendix 2. The principles are summarized in Table 1. A detailed description of the rationale and management issues associated with each point are given in Appendix 4.
The significance of the principles
Developing the principles and thresholds was the first stage of the project and they have been pivotal to the economic modelling as well as the communication activities of the project.
To our knowledge, this is the first serious attempt to fully synthesize the range of land management issues relevant to a production landscape and to quantify limits to resource exploitation from a landscape perspective. For this reason, the principles and thresholds have attracted considerable interest from researchers, extension officers, agency personnel and land managers. This interest has been intensified by the high level of activity generated by the Natural Heritage Trust program, and the numerous national state and regional planning activities with an interest in vegetation retention targets. Added to this is the growing recognition of salinity and biodiversity loss and various activities related to vegetation protection legislation.
Despite intense scrutiny, the scientific community has strongly endorsed the principles as being scientifically sound within the limits of the information available. It is important to note that our scientific knowledge is still incomplete and the thresholds in particular need further investigation. There have been some non-scientific concerns raised which can generally be related to one of the following:
- Philosophical disagreement that quantified limits to development should be proposed at all. This concern can be shared by some people having a pro-development or pro-conservation perspective, as a limit to vegetation clearing also implies an allowance for vegetation clearing.
- A perception that if the principles were implemented, all landscapes would be cleared down to 30%, regardless of their development current status.
Regarding point 1 we can only acknowledge that this is a difference of opinion. We understand the thresholds to be real, and that there can be frightening consequences to exceeding them (e.g. the loss of productive land to dryland salinity). Therefore, it important to formally recognize them.
Point 2 is more complex. It is true that if there were no other limits to development, that the thresholds specify a minimum of 30% woodland cover. However, this threshold is a minimum, and there is a hierarchy of other factors that affect the amount of woodland that may need to be retained or restored in a specific landscape. The principles take into account that it is not advisable to develop land beyond its capability, including retaining trees on steep slopes, water recharge areas and riparian buffer areas. The total retention (or restoration) rate could therefore be anywhere between 30 and 100% depending on the landscape (see Chapter 10, Appendix 4). There may be good reasons not to clear a landscape that has potential to be developed, but this would be based on other land-use objectives. The principles are identified as the ecological limits to development, given that this is the land use objective for the landscape.
Landscapes or properties
Another criticism that has been levelled at the principles and thresholds is that they have been developed for properties and are, therefore, not relevant to broader catchment or regional planning. The reality is that the information used to develop the principles is mostly related to landscape-scale evidence, or evidence that is scale-independent (e.g. neutral landscape models). We are not aware of emergent ecological processes that have been reported at the property scale, with the exception of Walpole's (1999) study of tree cover and property-scale production. The principles are therefore most relevant to catchment and regional planning. Our application to the problem of property planning has been based on the principle of equity (all landholders have a duty of care to manage and protect natural resources). We also believe that there will be some aggregative effect of good management at the property level that will reflect on the wider landscape. The context in which the principles were developed was that broader-scale planning was also proceeding, particularly in the requirement for a national network of conservation reserves (in addition to the environmental reserves on properties).
We do not know the range of scales at which all the principles apply, or could most profitably be applied. We are aware that collective and broader scale regional and catchment planning has the potential to produce good management outcomes.However, wide scale collective action was not a reality in the study regions at the time the project commenced. Producers were largely acting individually on a daily basis, and will continue to.
Table 1. General ecological principles for the sustainable management of grazed woodlands.
There are six main principles for sustainable management of grazed woodlands (sub-tropical grassy eucalypt woodlands). Further principles are defined under the main principles. The principles which are in italics are those that include thresholds (recommended upper or lower limits). These principles were first published in McIntyre, McIvor & MacLeod (2000). The wording, but not the intent, of Principle 5 has been revised in this version.
- 1. Property planning and management should include a long-term vision which considers the whole of the property and its place in the catchment.
- 1.1. Manage to the potential and limitations of the land, based on an understanding of ecological processes.
- 1.2. The precautionary principle of conservative or delayed development should apply.
- 1.3. Land uses of high intensity need to be balanced with significant areas of low intensity use across landscapes.
- 1.4. Land uses can have influences that spread beyond their boundaries so their arrangement across landscapes is important.
- 1.5. Vegetation representative of all the land types occurring on a property needs to be retained and managed.
- 2. Manage soils to prevent erosion and to maintain productive capacity and water quality.
- 2.1. Keep the amount of bare ground exposed to no more than 30-40% of the ground surface in pastures.
- 2.2. Place infrastructure in stable locations on the landscape to avoid erosion.
- 2.3. Some soil types require particular attention to avoid erosion and salt problems.
- 3. Manage pastures for production and to maintain the variety of plants and animals.
- 3.1. Graze conservatively to maintain dominance of tall and medium tussock grasses over 60-70% of the native pastures.
- 3.2. Limit the extent of intensive land use (grain and forage cropping, sown pastures) to a maximum of 30% of the property area.
- 3.3. Vary the management of pastures to provide for a variety of species and a diverse range of fodder sources.
- 4. Maintain local native trees for the long-term ecological health of the property and catchment.
- 4.1. There should be a minimum of 30% woodland or forest cover on properties.
- 4.2. Always favour natural regeneration of existing trees to planting and re-creating habitat.
- 4.3. To be viable in the long term, woodland patches should be a minimum of 5-10 ha.
- 4.4. Retain trees of different ages within stands to retain the long-term viability of tree populations.
- 4.5. Maintain or regenerate trees in appropriate places to minimize degradation, enhance livestock production and enhance diversity.
- 5. All properties require an environmental reserve for species that are sensitive to agricultural land uses.
- 5.1. Where possible choose the areas with existing flora and fauna values for ongoing management and include areas on good quality soils.
- 5.2. Retain critical habitat elements such as mature trees, understorey vegetation and standing dead and fallen timber for fauna.
- 5.3. Environmental reserves need protection from heavy or continuous grazing.
- 5.4. Ongoing weed control and fire may be required in environmental reserves.
- 5.5. Environmental reserves should be connected to others on the property or in the district.
- 5.6. Manage at least 10% of the property as an environmental reserve.
- 6. Watercourses are particularly important to the ecosystem and grazing enterprise, and require special management.
- 6.1. Vegetation should not be cleared up to the edges of watercourses.
- 6.2. As a general principle, livestock should be excluded from watercourses to reduce soil erosion and maintain the quality of water.
- 6.3. Control of exotic species in riparian zones is important
Objective: Quantify these relationships for at least one ecosystem that is economically important to the northern beef industry.
Our experimental work and the data synthesis described above have enabled us to specify for a particular landscape a best-bet estimate of management and property layout that is ecologically sustainable. The thresholds listed in Table 1 represent the quantified assessment of ecological sustainability in grassy eucalypt woodlands, using the best available scientific information. By comparing these with the status of the four case study properties we were able to identify the extent to which the properties were within, or exceeded the thresholds. These are detailed in Appendix 3 and summarized in Table 2.
Our overall assessment is that the soil and pasture resources have been maintained in good condition on all four properties, particularly those in the Crows Nest district. With one exception, the properties had not been over-developed in terms of tree clearing and intensive land use was generally within the recommended threshold. In Queensland, intensive land use has been associated with increased levels of insect-mediated eucalypt dieback (Wylie et al. 1993), and therefore, increasing pressure is placed on remaining tree populations. If tree regeneration potential is lost under these circumstances, the long-term future of existing populations is at risk. The property with the fewest trees (10%) and the most pasture development (32%),also had the lowest level of tree regeneration. Significant tree dieback was recorded in the blue gum and narrow-leafed ironbark populations on this property, indicating that it had entered a downward spiral of tree decline and accelerated tree death.
While the tree and pasture resource was in good condition for three of the properties, there were issues associated with the types and location of the retained vegetation and the management of riparian areas on all four properties (Table 2). Specifically, these concerned:
- The high level of clearing of vegetation types on the most fertile land types. This pattern is consistent with that of the rest of Queensland (Sattler & Williams 1999). It is an issue because of the loss of specific plants and animals that are associated with particular vegetation and soils. The fact that these vegetation types are poorly represented in the formal reserve system intensifies the problem.
- Livestock access to riparian zones and watercourses. The general recommendation from a wide range of sources is for stock to be excluded from these areas (Appendix 4, Ch. 7).
- The high level of clearing in riparian zones. This is related to the fertile land issue as fertile soils are often associated with the lower parts of the landscape and therefore to watercourses. These areas have a high level of importance to producers (for the level of production obtained), livestock (for access to water, shade and high quality forage) and wildlife (access to particular types of habitat and a stable food resource). Water quality and other pollutants are a concern to urban dwellers and downstream water users.
|Principle or threshold||Status of case study properties|
|1.5. Vegetation representative of all the land types occurring on a property needs to be retained and managed||All properties had at least two land types that had retention rates of <10% of original extent|
|2.1. Keep the amount of bare ground exposed to no more than 30-40% of the ground surface in pastures||The two Crows Next properties easily conformed to this threshhold and the Burnett properties less so.|
|3.1. Graze conservatively to maintain dominance of tall and medium tussock grasses over 60-70% of the native pastures.||All properties conformed to this sthreshold and had adequate densities of tall and medium tussock grass species.|
|3.2. Limit the extent of intensive land use (grain and forage cropping, sown pastures) to a maximum of 30% of the property area.||All properties conformed to this threshold with intensive development ranging from 0-32%.|
|4.1. There should be a minimum of 30% woodland or forest cover on properties||This threshold was met for three of the properties (range: 29-49% woodland cover). One property had only 10% retention.|
|5.6. Manage at least 10% of the property as an environmental reserve||Only one of the four properties had any land managed specifically for sensitive species and this proper;ty had a fenced off rugged asrea representing 1% of the property.|
|6.1. Vegetation should not be cleared up to the edges of watercourses.||Riparian vegetation was less than the buffer areas recommended from regional tree clearing guidelines (ranging from 34-56% of the suggested area).|
|6.2. As a general principle, livestock should be excluded from watercourses to reduce soil erosion and maintain the quality of water.||Livestock was not excluded from any watercourse on any property.|
Objective:Link these quantified relationships to measures of productivity, and thence to economic indicators of enterprise returns, and assess alternative management strategies for both economic and biodiversity costs and benefits.
Management actions to apply the principles involve controlling grazing by livestock, regeneration or retention of trees, planting trees, use of fire, and locating infrastructure such as fences and water. The most direct economic effect on grazing enterprises of pursuing these strategies will be a reduction in the available supply of forage for stock. This follows restrictions to grazing in certain parts of the landscape such as riparian areas and dedicated environmental reserves. Also, stocking rates must be reduced as timber density increases in the areas identified, as we considered the current grazing pressure appropriate under the guidelines and maintained it in the scenarios. The application of the forage and economic models to predict economic performance under the scenarios are detailed in Appendix 4 (Ch. 8). The results are summarized in Tables 3, 4 and 5.
|Salinity risk recharge area without woodland cover||145||1707||0||0|
|Additional woodland area needed for riparian buffers||41||333||59||112|
|Additional woodland area needed to ensure viable patched of all vegetation types||1||0||0||1|
|Aditional area to provide overall 30% woodland||25||0||0||0|
|Total additional woodland||212||2040||59||113|
As Table 3 indicates, the greatest requirement for woodland was to restore cover to recharge areas and riparian areas. Once this was done there was virtually no requirement to provide additional woodland to represent all vegetation types. This reflects the close proximity of fertile soils and watercourses. Only one property required additional woodland simply to meet the 30% minimum woodland threshold. The most heavily impacted property under the scenario was one that had cleared over 1700 ha of woodland for sown pastures on soil considered to represent a salinity hazard. Adjustment of the amount of pasture production available over the properties with the projected areas of woodland is detailed in Table 4. Reductions in forage production ranged from 8-23%.
By maintaining current utilization rates and adjusting herd size, it was possible to model impacts on gross margin and net profit for each property. Reductions in profit were $21K, $83K, $6K and $10K for properties A-D respectively (Table 5). These estimates of the impact on enterprise profitability of fully adopting the principles paint a bleak prospect for wide-scale action in the short term. The longer-term economic climate for extensive livestock production on grassy woodlands places limits on managers' scarce financial and labour resources. For example, ABARE (2000) surveys consistently reveal a significant proportion of specialist livestock enterprises are earning low net incomes and carrying substantial levels of debt. Some enterprises will struggle to persist in the medium to longer term. The ongoing and deteriorating cost-price squeeze is making conditions progressively worse. These are not encouraging signs for sacrificing present income for future and uncertain gains.
However, there is also an ecological imperative that underlies the need to implement the principles. Positive action needs to be taken. Moreover, this action will need to start with generally limited public support until the necessary institutions are in place to more appropriately balance private and public shares in the costs of the necessary ecological investment (Young et al. 1996; Binning 1997).
|Total Herd Size (adult equivalent)|
|% decrease herd size||22||23||12||8|
|Total gross margin ($'000)|
|% decrease gross margin|
|Overhead costs ($'000)||64||249||49||64|
|Net profit ($'000)|
|% decrease net profit||58||73||29||37|
The above reflections on levels of woodland cover to offset salinity hazards and to rehabilitate riparian buffers provide something of a clue for making the breakout and making some partial steps towards the ideal future landscape balance. We suggest that the costs of augmenting woodland cover to avoid salinity hazard might be reduced if we knew more, so that we could target planting to strategic parts of the recharge zone. Similarly, if we could reach a reasonable consensus on 'duty of care' for riparian vegetation, it might be possible to make some steps to achieving much of the gain that might come with full adoption. This is consistent with the notion of the Pareto 80:20 rule in which 80 percent of the gain might accrue to the first 20 percent of commitment, if this is strategically planned. In a major sense, this requires a re-framing of the question on adoption from "why?" to "why not?" and "how?".
Objective: Identify practical measures to conserve biodiversity that producers can incorporate within their sustainable management practices, together with simple indicators they can use to assess results and continue to adapt and improve management.
Our principles and thresholds provide a comprehensive framework of indicators to cover all major natural resource issues on grazing lands. Our approach differs from others in that we have used types and extent of land uses or landscape elements as key indicators. This is innovative in that we have developed indicators incorporating landscape-scale processes that are increasingly important. Land use is a deceptively simple but effective indicator of ecological sustainability. Given their simplicity, and ease of recording at the property scale, the main challenge is gaining acceptance of land-use indicators. We also need a stronger technical basis for justifying these indicators and their relevant thresholds. Current information is significant, but rudimentary.The broad land use indicators and their thresholds are illustrated in Fig. 3.
Figure 3: Three broad land-use indicators and their thresholds for maximum development on a grassy woodland landscape, that would be considered ecologically sustainable. With combinations of grazing and clearing, four land uses are derived.
Indicators that relate to the location or extent of woodland include the following:
- Vegetation representative of each land type retained (≥10% of each regional ecosystems type is the legal minimum at the bioregional scale and would ideally be applied at the property scale. Patches of vegetation should be a minimum size of 5-10 ha, depending on the surrounding land use)
- Extent of woodland cover on recharge zones (100% revegetation of recharge areas above salt sources used in scenarios)
- Riparian zones supporting native vegetation (using existing tree clearing guidelines)
The following indicators of pasture condition within land uses are relevant to cleared native pasture and grazed grassy woodland:
- Tall and medium tussock grasses dominate native pastures (Threshold: 60-70% of pasture area has these grasses dominant).
- Bare ground (Threshold: ≤30-40%)
Indicators of condition within environmental reserves include the presence of mature trees, understorey vegetation and standing and fallen dead timber. Thresholds have not been set for these indicators.
Some of the indicators are easy to monitor with tools as simple as a property map (intensive land use, areas grazed), aerial photos (woodland cover) and visual observations may be sufficient for informal monitoring (see Appendix 4, Ch. 10 for further discussion about the use of indicators and principles).
Practical issues associated with implementation of the principles are discussed in each of the chapters of the technical information manual (Appendix 4).Full implementation of the principles requires all the natural resource information that would be required to develop a farm plan. In some cases, accessing this technical information will make some indicators technically difficult to apply. For example, with salinity hazard mapping incomplete for northern Australia, the identification of recharge areas and potential salinity problems is difficult and requires on-site assessment by experts. Even then, hazards may not be identified reliably enough to justify major remedial works to managers.
Perceptions of practicality are affected by the motivations of the managers and the extent to which they might see conservation measures as being desirable. For example, the desirability of fencing riparian zones from livestock is widely accepted in southern Australia, and techniques are well developed (e.g. see Lovett & Price 1999). In contrast, the fencing of riparian zones was identified amongst the Management Panels as the most problematic and least practical of the potential management changes. Differences in perceptions of practicality may arise from:
- The issue is relatively new in Queensland; water quality issues have been subjected to longer and more intensive debate in southern Australia.
- The more extensive land use in the Queensland study area may make actual and/or perceived impacts of livestock on watercourses and water quality less evident. Most streams are dry for most of the year and they are generally stable.
On individual case properties, there are up to 70 km of watercourses identified for protection and the capital costs of implementation are extremely high (Table 6). Managers have argued that good grass cover is better for soil protection than trees. However, the role of trees in providing structural stability to banks and habitat for wildlife needs to be considered. The project team did not have the resources to adequately explore this issue, or provide solutions, and our observations are at odds with activity in northern Qld where extensive fencing of riparian areas is supported by National Heritage Trust funding. Because riparian areas and watercourses are of such great ecological and financial significance, an important area to explore is the trade-offs associated with riparian protection. The technical underpinnings of riparian management under the scenarios needs critical review and practical responses need to be identified. This is particularly important given pressures on northern Australia's wildlife and water resources will inevitably increase.
|Fencing riparian areas|
|Length of riparian boundary (km)||22||140||21||43|
|Fencing cost ($)||45,000||490,000||42,000||130,000|
|Off-water watering points|
|Number of points||5||16||6||11|
|Cost of watering points||20,000||64,000||24,000||33,000|
|Area planted (ha)||164||1,145||21||41|
|Cost of tree planting ($)||165,000||1,145,000||21,000||41,000|
|Total Capital Outlays ($)||230,000||1,699,000||87,000||204,000|
|Capital/ha of holding ($/ha)||219||168||88||116|
Objective: Assess whether the results of this project can be used to assist management for conservation of biodiversity in other ecosystems within northern Australia.
Through our numerous interactions with researchers and land managers Australia-wide, we have been able to consider the relevance of the principles and thresholds to other ecosystems (see following section on communication) and have discussed the topic in Appendix 4 (Ch. 10). There are three issues that are pertinent to the discussion of generality: the sources of evidence, the relevance of the land uses and existing landscape condition.
Sources of evidence
One objective of the project was to identify a minimum ecologically sustainable state for eucalypt grassy woodlands in south-east Queensland in landscapes that were variegated (i.e. intensive land use over 10-40% of the landscape, McIntyre & Hobbs 1999). We used specific ecological information on Australian grassy woodlands throughout their latitudinal range (tropical to temperate). Much of the information was drawn from temperate studies, but there were also significant observations from the tropics and sub-tropics (e.g. Wylie et al. 1993 on eucalypt dieback). The feedback that we have received indicates that, from an ecological perspective, the principles are highly relevant to all eucalypt grassy woodland systems throughout Australia, and can be directly applied.
Other significant evidence was drawn from theoretical landscape ecology (neutral landscape models) and empirical observations of ecosystems worldwide (McIntyre, McIvor & MacLeod 2000). Both sources of evidence informed the 30% woodland threshold (therefore the term woodland can be substituted for any major vegetation or habitat type relevant to any landscape). The 10% environmental reserve threshold is drawn from observations of representativeness of grassy woodland habitat and neutral landscape models. The notion of 70% habitat retention for organisms with low mobility is also related to neutral landscape models, but is complementary to empirical observation of eucalypt dieback in Queensland that support limitations of intensive land use to around 30%. Thus the landscape scale land-use thresholds have a fundamental biological relevance to all ecosystems.Where there is empirical evidence, it has turned out to be complementary to the theoretical predictions.
However, it should be noted that the empirical evidence is very limited and as more landscape-scale observations are made, the variation in landscape response (and methodological approaches) will become evident. If the theoretical predictions that we have used are sound, it will take many, rather than a few observations to confirm them.
Relevance of the land uses and vegetation types
This is one of the most easily identifiable 'objections' to generalizing. If a landscape does not support a grassland layer, then thresholds pertaining to grassland extent or condition are irrelevant. Similarly, if cropping is not practised on a particular landscape, the thresholds relating to this land use may appear irrelevant (although land use change can be rapid and the possibility of future intensive use should always be kept in mind). On other landscapes, shrub layers may occur instead of tree layers.
In some cases functional equivalents to vegetation layers and modified habitats can be identified. However, the principles would still need to be tailored to reflect the types of vegetation, the types and amount of land-uses or vegetation states, and the indicators of condition. This would involve reviewing the fundamentals of what the thresholds mean and how the land uses affect the biota. At the coarse scale, this may not be particularly difficult, but relies on a reasonable knowledge of the effects of management on the biota. Some 'top of the head' examples are given in Table 7.
|Intensity of land use or management|
|Landscape type (alteration state)||High||Medium||Low||Very low|
|Grassy eucalypt woodlands temperate to tropical (varigated)||Cropping, sown pasture (30%)||Cleared native pasture (40%)||Grazed grassy woodland (20%)||Environmental reserve (10%)|
|Tropical eucalypt woodlands (intact)||-||Heavily grazed in areas of high use (10%)||Grazed but uncleared (80%)||Environmental reserve (10%)|
|Woodlands (fragmented)||Cropping (60%)||-||-||Environmental reserve (40%)|
|Brigalow (fragmented)||Cropping, sown pasture (50%)||-||Grazed brigalow regrowth in rotation with cropping (20%)||Environmental reserve (30%)|
|Semi-arid rangelands (intact)||Heavily grazed, close to watering points (10%)||Grazed, intermediate distance from water (40%)||Grazed, large distance from water (40%)||Far from water, beyond the reach of livestock (10%)|
Existing landscape condition and land use
A fundamental barrier to generalization is that of existing landscape alteration state. An important example is that of intensive land use. A 30% upper limit to intensive land use is likely to be relevant to all grassy eucalypt woodlands owing to their susceptibility to insect mediated tree dieback. If development exceeds this threshold, we predict that there will be increased incidence of eucalypt dieback and, with increasing extent of intensive use, progressive local extinctions of plants and animals. However, in a predominantly (90%) cropped landscape, it would neither be economically feasible, or socially acceptable to suggest reducing intensive land use to one third of current. The discrepancy between the ideal and actual levels of land use points to severe ecological problems for these landscapes. Nonetheless, it is not necessarily constructive to present biodiversity ideals as management recommendations in the first instance, particularly when we need to better quantify the trade-offs between conservation and production on fragmented and relictual landscapes. Maintaining biodiversity is a different process to restoring it.
It is possible for principles and thresholds to reflect either ideal states, or pragmatic targets, as long as these are stated, and acknowledgement of potential compromises are made evident. For example in the principles and thresholds publication (McIntyre, McIvor & MacLeod 2000) we point out that under the scenarios, organisms with various combinations of tree-dependency, low mobility and grazing sensitivity will experience the landscape as fragmented and may therefore be at risk. This is probably the most difficult challenge to generalizing, as it is easy for important contextual information to be lost in the process of communication.
In Table 7, the scenarios for fragmented woodlands and brigalow reflect achievable rather than 'ideal' targets for these already highly developed landscapes. Because we know the viability of habitats can be enhanced by locating habitats in such a way as to maintain connectivity for organisms, this becomes an important strategy in landscapes where habitats are fragmented, and revegetation is only going to be undertaken to a limited extent. Within these less conservative management levels, intelligent landscape planning can do much to enhance the outcome for plant and animal conservation.
Objective: Proactively publicise and disseminate project results to the industry and others concerned with natural resource management in northern Australia, including providing assistance to producer-led management within NAP3.
In our communication plan (see Appendix 1), we identified seven -+areas of planned communication activity and have focused our activities in these areas. In addition to the these outputs (detailed below), we have produced six refereed scientific articles and seven conference papers (Appendix 1).
Learning module, the landscape game and associated workshops
The learning module 'Balancing Conservation and Production' is a presentation of the principles and thresholds in a non-technical format, with explanation of the ecological terms and concepts that underpinned the principles (see Appendix 2). The material was developed into a resource book for people working in extension and community learning areas. The module, and its introduction to stakeholders in a workshop environment, has been at the centre of the project's success. The draft module was presented at three one-day workshops in Bundaberg and Toowoomba in November 1999. In this phase,75 people, mainly extension, catchment and landcare co-ordinators attended.
Successful strategies were the careful design of the workshops and the use of a professional facilitator. The habitat connectivity game was developed as an exercise in the workshops and was a great success, being scored on average 9/10 while the rating for the three workshops averaged 8/10 (see Appendix 5).
An edited version of the module was introduced in a second round of two workshops in Toowoomba and Bundaberg in March, 2000. These workshops were also very well received by the great majority of attendees. The learning module was finalised in April 2000 and is being distributed in booklet form. An electronic pdf version is also available on the web. A total of 114 people attended the five workshops and the process was very successful in providing feedback to the module and eliciting interest in the project's outputs. We have subsequently distributed approximately 500 copies of the module and are still receiving requests from across the country and overseas.
Technical information manual
A draft technical information manual to provide the technical background for the module was completed in February 2001 and is appended (Appendix 4).
Field days and workshops
Field days and meetings were initiate and organized to involve the case study producers and the Management Panels in the review and assessment of the scenarios as follows:
- Field days in Auburn (July 1998), Mundubbera (September 1998) and Crows Nest regions (November 1998).
- A second round of meetings for the Management Panels was held to consider the economic implications of applying the principles on the case study properties (Auburn and Mundubbera - April 1999, Crows Nest- August 1999).
We wanted to more systematically explore the issues associated with adoption of sustainable management, with the three Management Reference Panels, particularly in relation to the principles and thresholds that have been the focus of our previous discussions. To achieve this, interviews were held with 26 individual panel members in February 2000 (Auburn, Mundubbera) and May 2000 (Crows Nest)
Open field days were held at:
- Crows Nest, November 1998.
- 'Stanley House' near Esk, in association with Beef Improvement Association, November 1999.
- 'Yerilla' Auburn River, near Mundubbera, September 2000.
The following presentations were made to meetings and workshops. Only those not resulting in subsequent publications are listed.
MacLeod N.D. Sustainable management of variegated landscapes for livestock production and nature conservation - Balancing ecology, economics and human preferences. Paper presented at Nature Conservation in Production Environments conference at Taupo, N.Z. (December 1997).
McIntyre, S. Human impacts on landscapes. Seminar, CSIRO Wildlife and Ecology, Canberra (May 1998).
McIntyre, S. Principles for sustainable grazing in eucalypt woodlands. Presentation to extension officers, Brian Pastures (November 1998).
McIntyre, S. Presentation on landscape design principles at workshop for MLA, UGA and pastoral industry representatives 'Biodiversity and grazing management', Brisbane (November 1998).
McIntyre, S. Principles for landscape design and management. Regional landcare and catchment forum, Mary, Burnett and Baffle Catchment areas at Brian Pastures, Gayndah (June, 1999).
McIntyre, S. Functional role of biodiversity. CSIRO Component meeting. Adelaide (June, 1999).
McIntyre, S. Co-convened (with Sandra Díaz, Universidad Nacional de Córdoba, Córdoba, Argentina) a symposium at the VI International Rangelands Congress on the theme 'Range Management and Plant Functional Types (July 1999).
McIntyre, S. Landscape game presented to Crows Nest Catchment Landcare Group (November 1999).
McIntyre, S. Presentation describing the principles and thresholds at a Nature Conservation Council workshop on setting targets for vegetation retention and revegetation in Sydney (March 2000).
Green, J. Landscape Game demonstration at Get Active Day, Tallebudgera (April 2000).
McIntyre, S. Sub-tropical grasslands. Seminar at Department of Ecosystem Management, University of New England, Armidale (May 2000).
McIntyre, S. Workshop to advise NSW National Parks on the identification of targets for bioregional conservation, Sydney (July 2000).
Green, J. Landscape Game Demonstration at Northern Grassy Landscapes Conference, Katherine (August 2000).
MacLeod, N. Presented information to the House of Representatives Standing Committee on Environment and Heritage Inquiry into impact of public good conservation measures on private landholders, Brisbane (September 2000).
McIntyre, S. Dr Pangloss visits south-east Queensland in 2010. Greening Australia's 2000 Conference at Gatton, (September 2000).
Martin, T. G. Data needs for planning for sustainable grazing. DPI workshop: Data needs and data integration for regional vegetation management, Brisbane (October 2000).
McIntyre, S. What is biodiversity? CSIRO Long Pocket Laboratory, Seminar (March 2001).
McIntyre,S. Setting vegetation targets to meet multiple objectives. Land and Water Australia Stakeholders' Forum, Barossa Valley, (May 2001).
McIvor, J. Identifying production-conservation tradeoff: the economics of beef cattle grazing with active conservation management in S.E. Queensland. Land and Water Australia Stakeholders' Forum, Barossa Valley, (May 2001).
McIntyre, S. Principles and thresholds for sustainable management of grazing lands. Talk at Southeast Queensland Nature Refuge Field Day, Esk (July 2001).
A project newsletter has been produced on a six-monthly basis (Appendix 1) between 1998 and 2001. Our mailing list has grown from 220 (Issue 3) to over 400 (Issues 4-6). Although it provides a useful way of maintaining contact with a large number of people, and we have had positive feedback, we think that the cost-benefit of producing a newsletter should be considered.
Media activities - radio and television
A Media Release 'Playing CSIRO's environment game' was released in March 2000. This attracted media activity including: Channel 10 evening news ; Good News Week on Saturday evening; ABC regional radio (including Queensland Country Hour); Indigenous Radio (4K1G); Radio Australia.
A major interview relating to landscape thresholds on Radio National (Earthbeat) was broadcast in March 2000, but was initiated through scientific connections rather than the media release. Other activities included a 'Totally Wild' TV segment on sustainable landscapes filmed on a case study property in May 2001 and an interview for CSIRO Awareness for Sci-Files on i) Landholder perceptions of the landscape principles; ii) Grazing and conservation. A CD-ROM containing the material was distributed to radio stations, October 2000.