What is natural capital?

At the recent Australian Government Economic Reform Roundtable, policy topics that were covered included: banking and finance, budget, business and industry, consumers and community, housing, economy, taxation and more similar. The stated aim of the event was, to build consensus on ways to improve productivity, enhance economic resilience and strengthen budget sustainability.

Natural capital was virtually ignored. Once again, our national health and wellbeing was being measured in terms of a budget bottom line and productivity.

Natural capital – the values of our natural environment – is essential to a prospering economy. The natural environment provides us with goods, services and amenity value that too often are ignored.  A healthy, functioning natural environment is the foundation of sustained economic growth, prospering communities, and personal wellbeing.

Many governments around the world critically and decisively include natural capital in their economic analyses and budget decision making. It’s time we did too!

 

Further reading:

Office of National Statistics UK – Natural Capital Accounts  

Environment EU – Natural Capital Accounting

Environment and Heritage NSW – Natural Capital Explained

World Bank Group – Natural Capital

State Government Victoria – Accounting for the Environment

Nodding Greenhoods at GWR

The Nodding Greenhood, Pterostylis nutans, is one of Victoria’s most common terrestrial orchids. (Pteron = winged, stylos = pillar or column, nutans = nodding or drooping). The Nodding Greenhood is an abundant and widely distributed species. It usually flowers from mid-winter to late spring, depending on local and seasonal conditions.

Typical Nodding Greenhood colony

Nodding Greenhoods are often found in a variety of habitats; sandy-rocky, moist-dry, etc., but nearly always shady. Sometimes they may only be a few centimetres tall, or you might come across some as tall as 10-20cms or more.

All native terrestrial orchids are a highly evolved plant species that have a symbiotic relationship with other plants, fungi and insects. Consequently, terrestrial orchids play a significant role in determining the ecological importance of a particular habitat and their presence - or not - can be an important indicator of the health of an ecosystem.

Ground-hugging leaf rosette

Nodding Greenhoods die down through summer and their ground-hugging leaves, stems and flowers completely disappear. Their energy though is stored within underground tubers, and come next winter, they begin to appear above ground again, ready for the next stage of their evolvement.

Showing the labellum with hairs

Most pterostylis species depend on a fungus gnat for their pollination and fertilization. The insect is lured to the orchid flower by a pheromone where it is momentarily trapped within the hood by the labellum ‘snapping’ upwards. Pollen is transferred to the insect as it struggles to escape. Upon release, the gnat flies to the next flower, so transferring the packets of pollen it has inadvertently collected, ensuring healthy cross fertilization of the plants.

Unusual double-headed flower

While checking the nest boxes (5x Ringtails, 1x Kreft’s Glider and 1x Antechinus - we think) at the Golden Whistler Reserve in Drouin recently, the ‘bird nerd’ team ticked about a dozen colonies of Nodding Greenhoods with probably a total of several hundred plants in flower – including a rare ‘double-header’.

Trees and lightning

Lightning is created by the buildup of electrical charge within a cloud. The static electricity is created by the particles of ice and water droplets rubbing against each other. Positive charge is created at the top of the clouds and negative charge at the bottom.

Credit: Bureau of Meteorology

A large voltage difference is created as the charges build within or between clouds, or between the clouds and the ground. Eventually, a rapid discharge occurs – a massive electrical spark. The lightning bolt heats the air around it – to something hotter than the surface of the sun – which causes it to expand rapidly creating a shock wave which we hear as thunder.

When the discharge occurs to the earth, it usually seeks a tall structure such as a building or tall tree for conduction to the ground. Some trees, especially those of high moisture content, are ideal electrical conductors. As the current passes down the tree, enormous temperatures cause any moisture, sap, etc., to vapourize and expand rapidly – the tree can ‘explode’. When the charge reaches the ground, the surrounding root systems may be compromised and the tree may take several months to eventually die.

Depending on the species, moisture content, location, etc., the effect on the tree can vary considerably. The tree may be destroyed, ultimately die over time or the strike may have no effect at all. Most eucalypts seem to survive lightning strikes rather well, even multiple strikes.

Climate scientists tell us we can expect more thunderstorms as the climate heats up. Around the world, there is an estimated 8 million lightning strikes each day. Lake Maracaibo in Venezuela is the most thunderstorm-prone place in the world with about 300 storms a year. Darwin has about 80 thunderstorms each year.