Monday, February 18, 2013

Do this NOW!



Black cockatoos need saving.

Stop logging our forests.
Giblett Block was saved by the persitance of forest blockaders stopping logging by living in the forset for many months. 


Keep big trees.
Old growth karri forest in the south-west of WA,


Plant more black cockatoo food plants.
Banksia grandis could easily be grown in gardens. Tough, local and adapted to the soil type.
This is a comprehensive list of black cockatoo food plants.

Increase urban forests.
Old Melaleuca tree at Uni of WA.


Grow some fruit and veg.

Endangered Carnaby's cockatoos eating pecans from a tree near  Fremantle, Western Australia.




Science is complicated - that's why not many people do it

Trees provide many things, including oxygen, carbon storage
 and happy dogs.
Science is complicated; that's why not many people do it and it doesn't always make sense to people that aren't educated about it. Science is also an incredibly varied field. I suspect that not everyone in the science of Sustainable Agriculture would agree with the scientists who create genetically-modified organisms. Many great disoverers had to battle for their theory to be seen and tested and proven true.
However there are times when lots of different sorts of scientists agree on things. One of those things is climate change.
Change is the word...things will change..A LOT. Some areas will be drier and hotter. Some areas will have devastating rains. There will be a lot of displaced people. These are simple observations, based on some really complicated science. Scientists don't know the exact details of whats going to happen because it is a really complicated system that has many variables. But overall, it looks like we've messed up bigtime and we may not get much of a chance to do anything about it (though I am still hopeful, otherwise I get sad and freak out!)

There are numerous links in an ecosystem between many different species. One tree, for example, can have hundreds of organisms living within its leaves, branches, bark and roots. Many of the smaller organisms may not even have scientific names but they could be really important. Without all the little decomposer beasties working for us, for free, there would be an awful lot of waste built up around us. The tree will also provide shade thereby cooling the air, and dirt and dust are also removed from the air as it passes through the leaves. Trees allow rain to soak into the ground, where the water is recycled through the tree, produces oxygen as a by-product (lucky for us) and releases moisture back into the atmosphere. Given enough trees that moisture forms clouds. One simple cycle among many millions of interactions that go on in nature , many that ecologists haven't had a chance to learn about yet.
Unfortunately many people think of trees simply as wood or paper, killing the tree and stopping it from doing it's many ecosystem services that it would provide for free. What are ecosystem services you may ask?

Ecosystem services.
Ecosystem services are the many 'resources' and processes that we get for free from nature.
These free services of nature fall into four categories: Provisioning, regulating, supporting and cultural.
Let me show some examples:
Provisioning: foods (plants, animals), water (rivers, lakes, dams), medicines (largely plant based), energy (hydropower, solar, wind).
Regulating: climate, carbon sequestration (forests, ocean), air quality (forests), pest control (beneficial insects), flood control (coral reefs, mangroves).
Supporting: Primary production (mining, agriculture, soils), nutrient cycles (fertilisation, decomposition), seed dispersal and soil building.
Cultural: Aesthetics, recreational, scientific discovery (medicines), spiritual.
There are many more things that we often take for granted, but there's a good chance it comes from nature.
This magnificent spot in the Helena-Aurora Range is in danger of destruction through mining. We shouldn't tale all that nature has to give us. We need to leave some for nature.

We have been using and abusing these free services for some time, without giving most of them a chance to recover. Not all of them are renewable either. Crude oil will run out, only so many minerals can be dug out of the ground before they run out too. Yet we continue to pollute and destroy large areas. Hasn't anyone noticed we're running out of habitable area? As cities expand they are build onto the very soils that enabled the city to be based there in the first place. How are we going to keep feeding people when the arable land is being over used and built upon?

An abandoned house in an abandoned town in the Goldfields.



Monday, February 4, 2013

Bores are not the best solution to watering issues.


Groundwater is a finite recource.
I find it really annoying when people talk about continuing to use bores and add more bores to Perth's shallow groundwater aquifers for watering gardens as though the water is going to magically keep replenishing itself.

The Perth Basin is an unconfined aquifer, meaning it is open to the air, showing up above ground as wetlands and lakes. Decreasing rainfall over many years and land use change as bushland is cleared and surfaces across the suburbs have been paved reduces the infiltration of rain water back into the   recharge areas of the Perth Basin metropolitan aquifers. Water is being taken form these area much much faster that it can be replaced by natural rainfall.
Guage pool in the hills near Perth.  The rate of flow into Perth dams has reduced dramatically in the last 30 years.

Yet more and more people have installed bores over the years and they are allowed to water more often each week than scheme water users. I believe this allows bore users to continue to ignore the efforts of the Water Corp and Dept of Water to wean us off our European strength water use even more than the general population. Sadly the Water Crop and Dept of Water seems to waste just as much as anybody.

A huge amount of water gets lost through leaks in the system, from dripping taps and leaking toilets to large scale leaks along water supply lines so we all need to do our bit to preserve the precious resource.

One of Perth's dams, showing the low water level.
The third source of water in the Perth area, after dams and aquifers is from the desalination plant. This water costs a lot of money to produce so it too needs to be used more prudently into the future.

Problems of using too much bore water.
Saltwater intrusion can occur where too much fresh water is removed by bores, allowing the salty water below to replace the fresh.

High nutrient levels in some aquifers due to fertiliser over use on the soil above them has enriched the groundwater to the point that bore water is feeding plants as well as watering (and no, this isn't really a great thing). I've had two quite trustworthy sources tell me this but haven't read a report on it.

Rainwater collection
Watertanks are brilliant, however with useful Perth rainfall generally only falling during the winter months, to get the maximum use out of a reasonable sized water tank it should be plumbed into the house for laundry and toilet use so it can be used instead of scheme water throughout the rainy months.

Collecting rainwater to water your garden in winter is not going to make a lot of difference, as the water can end up being stored for a while until the rain stops, unlike if the tank is plumbed to the house, where it gets to empty and refill regularly, making better use of the available ongoing rainfall throughout the season.


Waterwise gardens
The waterwise message in garden is slowly getting through and other water saving technologies are being used, such as greywater systems and low pressure sprinklers that make large droplets and therefore avoid misting which wastes a lot of water to evaporation.

We live in a dry city on a dry continent and must look for better ways to reduce our water use. Itn's not vey energy efficient to turn salt water into fresh, so we'd be better not to pollute or waste what little we have. Turning off taps properly and fixing leaks makes a huge difference over time.

waterwise help for you


Soils underlie a great deal of our lives and lifestyle.

Without soil we wouldn't eat (and no smart comments from aquaponic people).  Billions of people get fed because soil provides the nutrients and space for food to be grown. As time goes by there are more and more people moving away from rural areas and into the urban fringe. Farmers are abandoning their land in increasing numbers as water scarcity and the cost of fertilisers increase.
Who is going to keep growing food for the bilions of people on the planet and how can we keep doing it if we don't look after the soil properly?

Soil scientists are looking at these questions and hoping that through technology and a certain amount of common sense that increasing numbers of people can be fed on ever decreasing viable farmland. Coupled with a peak phosphorus event sometime in the next decades, there will need to be a lot of changes in the way soils are treated and improved. Some of the solutions lie in going back to traditional farming, such as no-till and use of cover crops. Some solutions lie in the use of technology to increase precision agriculture, using  satellite imagery to determine what areas in paddocks need a particular nutrient or water. Precision farming allows farmers to only use mininal amounts of fertilisers when they are needed and gives the farmer more time to do other things.

There are many techniques to grow food and provide for the people on the planet but we need to stop making so many people and stop wasting so much food.

Summertime is tough in Perth

Just a few of the things going on in the garden. It's hot and dry out there at this time of year. We've given up in certain parts of the garden but the potted orchard and a few other favourite things are still going well.
Strawberry guava, with ridiculous amounts of fruit forming.

Grevillea Robin Hood, to hide neighbours and attract birds.

Dragon fruit flower

Yummy figs, picked before the rats get to them.

Caper bush. Tough plant that takes lots of sun and loves limestone.It has pretty flowers too.