NSW DPI and biodiversity
Date: 26 Oct 2004
What is ‘biodiversity’?
Biodiversity is an abbreviation of the term ‘biological diversity’, and is defined in the National Biodiversity Strategy (available from the Australian Government Department of the Environment and Water Resources website) as:
The variety of life forms, the different plants, animals and microorganisms, the genes they contain, the ecosystems they form, and the interactions between life forms and the environment.
This definition is broad and includes both native and introduced species. Biodiversity ensures the continued existence of a healthy planet and our wellbeing. Many biologists believe that ecosystems rich in diversity have greater resilience and are therefore able to recover more readily from stresses such as drought or habitat degradation. When ecosystems are diverse, there is a range of pathways for ecological processes, so that if one is damaged or destroyed, an alternative pathway can be used. If native biological diversity is diminished, the functioning of ecosystems is put at risk. (The current state of biodiversity research in NSW is available from the NSW Biodiversity Research Network website.)
There are three levels of diversity:
- genetic diversity, which enables species to adapt to changes in their environment and survive;
- species diversity, which gives us the rich variety of life on earth (the total number of species is somewhere between 10 million and 100 million);
- ecosystem diversity, which gives us a variety of habitat types and ecological processes.
Australian biodiversity is particularly rich. It is classified as ‘mega-diverse’, which means we have a huge range of species, and it has a high endemism ranking, which means many of the species are unique to Australia.
Threats to biodiversity
Land clearing for agricultural use is the major threat to Australian biodiversity. Since European settlement in the eighteen hundreds significant clearing of the native landscape for the development of agriculture has occurred. Though broadscale clearing in NSW has ceased (through the introduction of the NVA (2003)), cleared land still impacts on biodiversity.
Other threats to biodiversity include:
- invasion by species alien to Australia
- changed fire management practices
- climate change.
The impacts of climate change over the next 30 years are predicted to have alarming impacts on Australia’s ecosystems and species. A Commonwealth Government study has predicted that for between 82% and 84% of Australia’s listed threatened vertebrates, the distribution of core habitat will contract, with the habitat of some species disappearing completely.
Key threatening processes
The NSW Threatened Species Conservation Act 1995 lists key threatening processes, for example:
- clearing of native vegetation (as per Scientific Committee determination);
- predation by feral cats;
- anthropogenic climate change.
A list of the key threatening processes is provided on page 33 of the Act’s Schedules.
The Australian Terrestrial Biodiversity Assessment 2002 states that vegetation clearing is the most significant threat to species and ecosystems in eastern Australia. Fragmentation of remnant vegetation, increased salinity and firewood collection are threats to biodiversity in the highly modified regions of southern and eastern Australia. Other widespread and pervasive threats to biodiversity include overgrazing, exotic weeds, feral animals and changed fire regimes.
What is being done to protect native biodiversity?
Biodiversity is being protected with the establishment of national parks, off-reserve conservation areas on private land, native vegetation clearing controls, development of the National Biodiversity Strategy and the NSW Biodiversity Strategy, and legislation.
Biodiversity legislation
Environment Protection and Biodiversity Conservation Act 1999 (Cwlth)
- Environment Protection and Biodiversity Conservation Act (from Department of the Environment and Water Resources)
Under this Commonwealth legislation, which came into effect in July 2000, any new developments that may have a significant impact on a matter of ‘national environmental significance’ require the approval of the Federal Minister for the Environment. These matters include:
- threatened species and ecological communities
- Ramsar listed wetlands
- listed migratory species
- World Heritage properties
- Commonwealth marine environment
- nuclear actions.
Penalties for breaches include fines of up to $5.5 million, restitution, and up to 7 years imprisonment.
Threatened Species Conservation Act 1995 (NSW)
This Act came into effect in January 1996. It provides for the protection of all threatened plants and animals native to NSW, where 398 species are listed as endangered, 391 as vulnerable and 79 presumed extinct. There are also 28 endangered populations, 60 threatened ecological communities and 16 key threatening processes listed in the Act’s Schedules.
Australian Terrestrial Biodiversity Assessment 2002
This assessment makes several recommendations to improve Australia’s biodiversity, including the following:
- Improve land use planning.
- Protect key natural areas.
- Rehabilitate key degraded resources.
- Help people understand how natural systems operate and how to maintain ecosystem function, biodiversity and sustainable production.
- Integrate biophysical, social and economic needs in decision support systems.
- Integrate biodiversity outcomes in best management practices.
- Establish demonstration sites.
- Develop policy that benefits natural resource management.
- Provide incentives to offset landholder costs in managing biodiversity.
- Legislate and regulate to support natural resource outcomes.
- Monitor and evaluate progress.
Biodiversity in agriculture
Biodiversity in agriculture is an important issue. Agricultural systems rely on the ecological services created by biodiversity. At the same time, agriculture has created a highly simplified biodiversity for efficient production. Agricultural practice has reduced the genetic, species and ecosystem diversities by:
- clearing trees and draining wetlands;
- growing a limited range of crops, usually as monocultures;
- raising a limited number of animal species, often unsuited to Australian soil conditions;
- using chemicals to control species that threaten production output;
- breeding selectively to reduce diversity within agricultural plant and animal species.
We are now seeing first hand the impacts of this reduced biodiversity:
- Tree clearing has led to rising watertables and increasing salinity, and species decline due to habitat loss.
- Monoculture cropping systems have less resilience in combating disease and pests.
- Overgrazing by agricultural animals has resulted in soil erosion and compaction, and loss of native grass species.
- Chemical use has reduced species diversity and created insects and weeds resistant to commonly used chemicals.
- Selective breeding has reduced species resistance and adaptability.
NSW DPI activities to manage biodiversity
NSW DPI is now focusing on production systems that encourage and enhance all aspects of biodiversity:
- diversity of farm enterprises that suit the environment;
- cropping/grazing systems that incorporate rotations of different plants to enhance soil health and break disease cycles;
- rotational grazing systems that enhance plant, soil and animal health;
- integrated pest and disease management strategies that harness the work of predatory insects and reduce pesticide use;
- native grass research to restore native plant communities and expand the use of native grasses in grazing;
- soil health research to restore biodiversity of soil microbes and insects;
- targeted pest control programs to eradicate feral animals;
- targeted weed control programs;
- involvement in native vegetation management planning;
- landscape management to farm within the capabilities of the soil and topography.
Author: Rebecca Lines-Kelly