'Mega' solutions are not necessarily the best approach to large-scale environmental problems. In fact, as our story on page 4 demonstrates, the solution to one of South-East Asia's, and the world's, biggest vehicle pollution problems – the millions of two-stroke motorcycle and tricycle engines belching fumes into the atmosphere – can be as simple as a low-cost engine retrofit.

Retrofitting the engines of smoke-belching Philippine motorcycle taxis to reduce pollution could cut their fuel use more than 30 per cent and emissions by 90 per cent according to non-profit US company Envirofit.

Western Australia is the only place in the world where native tuart trees (Eucalyptus gomphocephala) grow, but an unknown cause is killing them. Researchers warn that, within a single generation, the core population of WA's tuart forests could be gone.

The genetic library of the microscopic algae that feed corals the world over is revealing important clues to improve our understanding of coral bleaching and, ultimately, climate change.

A Canberra company has developed a domestic grey water recycling unit that can recycle 660 litres of water a day, reducing the amount of water purchased by a typical household by 50–60 per cent.

Australian scientists are training foresters in Asia-Pacific countries to measure carbon storage in trees, enabling these nations to gauge their contribution to achieving carbon targets and to participate in carbon trading markets.

Australia's Weeds CRC has developed a web-based tool to help gardeners and land managers choose native plants to replace weeds with fleshy fruit, such as camphor laurel and lantana, which have become an accessible food source for native birds.

The Desert Knowledge Cooperative Research Centre (CRC) is calling for private investors to partner with remote Aboriginal communities in an innovative business development.

A University of Technology Sydney scientist is developing guidelines for assessing the health of groundwater ecosystems.

In 2002, a group of young Melbourne engineers – interested in doing volunteer work for disadvantaged communities, but finding no ready outlet for using their vocational skills – got together to form Engineers Without Borders (EWB) Australia.

The 2007 Dow Jones Sustainability Index (DJSI) ratings announced recently in Zurich, Switzerland, included three Australian banks among the 25 banks globally that qualified for inclusion in the DJSI.

Australians blow and wipe their way through over 195 000 tonnes of tissue and toilet paper a year, but only 3.1% of this is made from recycled paper, according to figures from the Australian Plantation Products and Paper Industry Council (A3P).

Critics of photovoltaic (PV) technology have pointed to its high cost relative to other renewable energy technologies. However, US company NanoMarkets has forecast a 75 per cent decrease in cost over the next decade due to developments in thin-film PV (TFPV) technology.

In a letter to the journal Nature in August, four UK scientists warned that an increase in near-surface ozone concentration from industrial sources is likely to markedly reduce plant productivity.

Today it's not enough for manufacturers to make the cheapest or best-quality on the market if the product, or its production, use and disposal leave a big environmental footprint. Product stewardship requires key stakeholders to share responsibility for product impacts – an idea that's slowly catching on in Australia.

Everyone seems to be talking about sustainability. But are we all on the same wavelength when we use the term? Steve Hatfield Dodds – senior CSIRO researcher and President of the Australia New Zealand Society for Ecological Economics – begins a series examining the meaning behind this often-invoked word.

Over recent months, teams of school students throughout the eastern states have been designing and building their entries to compete in the second International Solar Boat Challenge.

This spring and summer, a flag at Caulfield Junior College, in Melbourne, Victoria, will be raised every time the UV index is high.

In his latest book, On Borrowed Time, leading Australian ecologist Professor David Lindenmayer writes that biodiversity loss is 'the most significant environmental problem facing Australia'. In fact, he continues, we are 'in the midst of the planet's sixth great extinction event', now being driven at alarming speed by human intervention. This edited extract highlights two of the 10 key environmental problems facing Australia.

Jane Goodall's visionary program for empowering young people to get involved in making their community and their environment a better place for all has taken root in Australia.

Australia has the potential to become an energy leader in the carbon-constrained future – but first we need to make sure we are heading in the right direction.

Short-listed and winning entries from the 2007 ANZANG (Australia, New Zealand, Antarctica and New Guinea) Nature photography competition – the most prestigious of its kind in the Australasian region – have been brought together in a new book published jointly by ANZANG and CSIRO Publishing.

As the Natural Heritage Trust celebrates its 10th birthday and moves to its third phase, Sophie Clayton examines its evolution, achievements and lessons learned along the way – including the important legacy of community capacity building.

They've been blasted with noise, even shot at, but birds – common and endangered – seem to gravitate to airports, creating a flight hazard. New Zealand authorities are looking at two low-impact solutions to the bird-strike problem.

Waiting around for someone else to do something about the reduction of greenhouse gases is not on the agenda for this highly motivated community group in central Victoria.

The second part of a series in which electrical engineer Peter Seligman reveals the hidden patterns of energy consumption and greenhouse gas emissions around the home. In this issue, domestic hot water goes under the microscope.

Managing Water for Australia looks at the emerging social and community challenges that stand in the way of implementing the National Water Initiative (NWI) – Australia's 10-year plan to improve water management.

If you're looking for a cause, now is the time to stand up for the deep ocean. This cold and dark world of continental slopes, mid-basin ridges and ocean floor plains is in need of advocates – more people, scientists and governments willing to show their hand for 'the silent deep', as Tony Koslow describes it, and support the precautionary principle of conservation.

Thanks to an innovative community organisation known as the Birchip Cropping Group, farmers in Victoria's north-west Wimmera Mallee region are being encouraged to establish low-cost wildlife ponds on their farms, to help maintain biodiversity as the area replaces its open channels with pipes.