I’m sure there are many contributing factors, but here’s a big one, in my opinion. In many parts of south-eastern Australia, prior to European settlement (1788) there were local shallow groundwater systems in the landscape which among other things led to so-called “swampy meadows” in the valley bottoms. These swampy meadows slowed the movement of water through the landscape and kept it hydrated. When Europeans came along, they cleared a lot of the trees so that they could farm on the landscape. As a consequence the water tables lowered, and the landscape began to dry out.
Wetter landscapes are surely more resilient to drought. I’m no ecologist but I have to imagine that fire won’t rip through wetter landscapes as quickly as it does through dry landscapes.
The drying of the landscape led to problems with gully erosion too as water could move faster through the landscape.
A grazier and race horse breeder called Peter Andrews devised a method of farming called “natural sequence farming” which aimed at restoring the natural hydrology of south-eastern Australian landscapes, including reestablishment of the swampy meadows. I guess we could call it a type of regenerative agriculture that is tailored for a specific landscape. The results appear to speak for themselves but for reasons that escape me it has all proven to be hugely controversial.
I’ve yet to hear, what was the source or sources of ignition for the Australian fires? Amazing how much land has burned in a relatively small amount of time. Some stats on wildfire acreage in the US in case of interest: https://fas.org/sgp/crs/misc/IF10244.pdf
@tomc15 that was an interesting link regarding housecats and foxes. Are the housecats out in the landscape away from town edges and wildland-urban interface areas?
That sounds like the sort of thing I’ve been wondering if it were possible for most of my life. Thanks for the post, I’ll look that up. I know it’s location-specific but there are bound to be some general principles involved, even if its just the way he arrived at it. And the way its rejected.
Yes and no, the junipers that were planted is a native species but I haven’t seen any naturally growing. The valley to east though is loaded with them and it happens to be a dryer valley, more desert-like habitat. I’m not a ecologist, all I know is the junipers are going down in the next few years when the hawthorns and other deciduous plants we planted get rooted and start maturing.
I do know that this year was one of the wettest years we’ve ever had on the marsh and several roads that were built on the dikes of the marsh were washed out this spring because of the water levels. I’m not sure how that affects the water table and such.
You’re welcome! You’re on the North Island, aren’t you? You may also be interested in learning more about the regenerative agriculture they’re practicing at Mangarara Station in the Hawkes Bay. I visited there on a conference field trip a couple of years ago and the owner Greg Hart showed us around. He’s a big proponent of permaculture and regenerative grazing techniques among other things. He’s fairly sold on it but he’d also love the scientists to come in and try to quantify once and for all whether his practices are making a real difference on his farm environment or not.
Yes, I’m in Auckland, a couple of hundred miles North West of Hawkes Bay (I think:) My geography is terrible). EDIT I see you are in Christchurch, so you probably know where Auckland is:)
There is a wildfire in Napier at present, 15Ha or 30(?) acres of forestry, last news I heard.
UPDATE It has now burnt 140Ha.
I have come to the reluctant conclusion that for many decades at least there has been enough knowledge around to support all the necessary changes to the problems we are currently aware of; but as a combined entity/society/species, we have not been sentient enough, as Charlie put it earlier in the thread, to value the subject, let alone to put into practice the knowledge. I can only hope a change is on the orange horizon.
Yeah, wetland loss is a huge and often ignored one with California. There were once wide swaths of riparian forest with cottonwoods and sycamores and such, which act as natural firebreaks. In the mountains there were ‘cienegas’ - wet meadows of various kinds. The floodplains were either cleared for agriculture or died when the water was taken out of the rivers. The cienegas have dried up due to grazing-related erosion and gullying, loss of woody vegetation associated with invasive species, more recently climate change, and other factors. Beavers also used to have a significant presence on the California landscape and their removal from most of the state has resulted in significant wetland loss as well. Overall, California has lost something like 95% of their wetlands, which doesn’t even necessarily include all of the floodplain forests which are not all technically wetland. So this series of natural firebreaks, safe spaces for animals during fires, and huge sponges that released water and kept the groundwater high, keeping trees less flammable… is totally gone. Now in California there is push to do mnore ‘fuel management’ but little if any push to restore the wetlands which not only would help a lot with the fires but would also help with the flood and drought issues there… which are very severe because of all the factors mentioned above and becoming worse with climate change because both flood and drought are becoming more frequent and severe.
So yeah… restore wetlands. Almost forgot- they sequester carbon too. It’s a huge no-brainer except it doesn’t happen much. Though a few groups like this are also working on it, and maybe there are more now than when i lived there. Still not nearly enough
yes, indeed. Because they are wonderful in themselves, as well as for the more overarching issues.
But - if a wetland area has become dry, or drier, and you plant in it, or allow it to develop wild, wouldn’t it produce the “wrong” kinds of species, just creating more fuel? I have no idea, am just struggling to adjust my own activities and ideas to having realized only a year ago that just letting any locally native vegetation continue to grow as it will, minus the exotics, is not necessarily a good thing, for reasons of fire if nothing else.
I live in Cape Town. Similar fire-adapted vegetation to California. We learn - to recognise when the air looks, wrong, murky. Where is the fire? That instinct sits deep within us, and is honed each time we live thru another fire. For us on False Bay sometimes the wind is driving smoke from a fire far away up the coast.
the biggest part of wetland restoration is often restoring hydrology… plugging ditches, fixing streams, etc. Often the plants and animals come in on their own unless it’s a very isolated site
thank charlie, that makes sense, (except that I don’t know what’s meant by “fixing streams”, other than preventing pollution including eutrophiciation from decay of nitrogeous plant material nearby). Do you have to control the earliest plant regen if its the wrong sort, even though native?
Radiata pine, another highly flammable tree apparently, is the species most planted here, for forestry.
An interesting (but New Zealand-specific) in-depth discussion of tree species for planting (and funding directing the species choice) in relation to diversity, native habitat and species protection, carbon sequestration, and fire, here: https://www.newsroom.co.nz/2019/09/09/788817/nobody-loves-radiata
To justify my inclusion of NZ in this thread - the Napier NZ wildfire in forestry land reported 19 hours ago as 15Ha/45 acre remained out of control this morning due to high winds preventing intervention, last reported as covering 300Ha/ 450 acres.
UPDATE Last reports were it increased to 350Ha sometime today, but is now contained.
@tonyrebelo could tell us about streams flowing again, as the Tokai pine plantation is removed, and endangered fynbos returns from the seedbank and adjoining Table Mountain National Park.
The sources of the fire ignitions here in Oz are a combination of lightning origin being the majority, plus deliberate and accidental ignition. However most of the fires now have been started by embers as a result of the impacts from existing fires. Conditions here are so dry and hot that anything that starts are difficult to stop. Doesn’t help that many are in remote forest country that is inaccessible, so can’t control it easily anyway, even if conditions did suit.
@trickman the cats are now what we call feral, ie effectively wild. They inhabit all parts of Oz, including the remote central desert country, all forest areas. Many of these areas the feral cats have evolved into what have been tentatively described as sub species or genotypes (though I am no taxonomist). The feral cats in the central desert country are now desert specialists able to survive exceptionally well, and do not closely resemble housecats. They are also huge - with many trapped animals 8-10kg (17-22lbs).
@crellow you are right about much of the landscapes pre european - at least in the higher rainfall areas. The majority of the smaller waterways were the chain of ponds style, with large areas of wetlands. This meant that water flows were slowed, vegetation growth was extensive. Europeans came and drained the wetlands and straightened the meandering waterways- resulting in these becoming channelised waterways. The clearing of the vegetation often resulted in gully erosion and channelisation of waterways, loss of the chains of ponds and increased speed of water, so it now flows out of the landscape quickly instead of being retained and spread out.
This is something that Peter Andrews identified and has designed techniques to slow water flow, retain it in the landscape. I had some dealings with Peter years ago, and like many visionaries, he has a talent for pissing people off. A very difficult man to deal with, particularly if you question anything he proposes, and completely inflexible in regards to his recommendations. Personally I think he is a brilliant observer and spot on about the history and need to restore waterways and wetlands to some extent. However, he is a promoter of weed species in this process such as willows (they are a pest in Oz), when he and others have had great success with native species in places. This puts him offside with many government bodies currently trying to remove willows.
Sydney Morning Herald article about an example of Australian indigeous or “cultural burning” resulting in complete protection of a property (the above link is to a reprint in the NZ online media outlet “Stuff.co.nz”)
yeah during the 20th century lots of places tried ‘restoring’ or ‘enhancing’ wetlands with inappropriate non-native species that turned out to be invasive… it doesn’t work and it isn’t necessary either. Too bad.