Am thinking this speaks to the profound truth that everything in our world is interconnected, and the health of one part directly impacts the whole. The idea of rivers as living networks, rather than just channels for water, is a perfect metaphor for the intricate web of life on Earth.
While out on many river's in my lifetime, it's not lost on me that the flow connects mountain streams to sprawling deltas, nourishing the land and all its inhabitants along the way, our own lives are part of a continuous cycle of connection.
I like to think when we mistakenly see a river as a singular, isolated entity, we fail to recognize the myriad of relationships that define its existence. Remembering the insects that feed the fish, the birds that nest in the trees on its banks, the groundwater that sustains it even in drought. It's now more than ever important to teach the concepts of the circle of life in its truest form: an endless loop of give and take.
I hate that when we disrupt this cycle by damming, dredging, or polluting rivers, we do more than just alter their physical course. We failed with our Corps of Engineers in our human efforts break what is natural to suit our own need to conquer and harness bodies of water.
We certainly didn't understand the consequences when we severed the links between species and ecosystems, leading to a loss of resilience and an inability for the system to recover.
Similarly, when we fail to nurture our own connections to the world around us—to other people, to animals, to the natural environment—we weaken our own collective strength. We lose the ability to adapt and thrive together.
Your call to "share the love for healthy, functioning rivers" is therefore not just about conservation; it's an invitation to acknowledge our place within this grand, interconnected network. By working to restore and protect these living arteries of our planet, we are also nurturing our own connections to all creatures.
I find your in-depth explanations refreshing and a very worthwhile. Looking forward to your next post on this important topic.
Wow -- how beautifully said! Thanks for your thoughtful comment. I don't want to say much in response as your thoughts are bang on and speak for themselves! Thanks! :)
Wow this is a completely new perspective on two of my favourite things. Rivers and trees are connected in so many beautiful ways and both give life. Thank you for writing this.
I’d love to understand more about the interaction between groundwater and rivers. Three rivers meet in my village. Two are part of a hydro power scheme so the flows a partially controlled. The third is a classic gravel bed river, draining mountains and braiding among shifting islands on its floodplain (where the village stands!). It is prone to flash flooding because the hills are denuded of trees through centuries of sheep farming and now hundreds of red deer.
A new pattern has emerged in recent years that has been particularly striking and long lasting - all the feeder springs, streams and ditches dried up in the spring and are waterless. The groundwater level seems to have sunk deeper below the surface into the alluvial gravels below our feet.
That's not good to hear. Could be a signal of climate change or mismanagement by the hydro scheme or just over-extraction of the groundwater for drinking. Are they glacial fed? But yes, sounds like groundwater depletion.
I loved reading about how important rivers are and their relationship with all manner of species. I guess it's hard for a lot of people to understand what they can't physically see. They just see water or perhaps some fish. Wouldn't this topic make a great Television series! You should team up with David Attenborough! Your explanations are spot on and I'll look forward to reading more.
When you mentioned "hierarchical dendritic networks" I became excited thinking you might dig into self-similarity at varying scales and fractal dimensions. Streams flowing into a river / from a delta and water transpiring up a tree trunk are similar optimisations to achieve economy of energy.
Ha -- yes, I thought I might lose my readers going into that direction too far. But yes rivers networks are fractal. It's fun simulating river networks. There are tools out there for making like easy to do so using Optimal Channel Networks.
This is a fantastic post, Jonathan, and such a needed reminder that rivers are more than linear systems. One key oversight I have always found in the River Continuum Concept is how little attention springs received in that framework. Headwaters, which form the foundation of the continuum, are for the most part spring fed. The unique ecological signatures we see in headwater streams, from stable thermal regimes to highly endemic invertebrate communities, are in large part driven by the influence of springs.
Without springs, most rivers globally would be ephemeral. Their constant discharge underpins the hydrologic stability that makes perennial rivers possible in the first place. Beyond hydrology, springs also shape biodiversity patterns: they introduce heterogeneity across headwater habitats, creating the mosaic of community compositions that ultimately scale up to the network level diversity you describe here. Of course, there are exceptions such as in ice dominated watersheds, but across most of the globe springs remain the primary source.
If we are rethinking rivers as networks, then springs should be recognized as the nodes where rivers are literally born, places that drive both ecological resilience and biogeographic uniqueness.
Let me know if this interests you and we could discuss more. I think its worthy of a manuscript.
Thanks Joseph! Absolutely a topic of interest. Much of my PhD was spent looking for spring-fed streams as I was interested in the role of habitat stability on diversity. Happy to chat more!
I actually have a review paper in review right now about the role of extreme events on river biodiversity and have realised I don't touch on the importance of springs as refuges so might try to sneak that into the final section after the next round of review.
I was up in northern Maine (south branch pond area) during the tail end of this years droughty conditions. I didn’t want to filter warm pond water if I didn’t have to cause I like cold water / ideally spring water. I had time and it was rediculously hot and humid so I kayaked over to the largest inlet drainage and I walked up a dry cobble gravel stream bed for about 10 minutes (1/2 mile).
Eventually I saw pools with stranded but seemingly happy (fast moving) trout and finally a couple hundred yards upstream I found a continuous section of “gaining stream” with ~55 degree F ground water to filter and drink.
I mentioned this to the ranger in passing when I inquired about the fishing rules and he said walk down the outlet stream and you’ll find the same thing.
What I would be super interested in is how trout, insects, etc utilize the river bed morphology and substrate for shelter during intermittent high peak flow conditions that break the drought.
Are they taking refuge in the deep pools? Is there an edge effect they are also taking advantage of? Do they just bury themselves in between the cobbles? Where do they find refuge during the transitional condition my story is about?
Trout would mostly move to spots where there are back-eddies etc. where the flow is slack. Mostly likely along the margins. Some fish burrow into the substrate, but depends on the river. In NZ, we have very dynamic rivers and many of our natives will burrow several metres under the substrate because there's a whole bunch of large cobbles with lots of interstitial spaces between them. Invertebrates, again species specific. Some just hold on (they're quite flattened in form), some have silk attachments that stops them drifting, some burrow etc.
Finally, if these high flows are predictable, they may be triggers for a life-cycle event like spawning, migration etc. In NZ some of our native fish lay their eggs in river margins above the water line waiting for a high-flow event to wash their eggs or larvae out to sea for juvenile rearing.
Am thinking this speaks to the profound truth that everything in our world is interconnected, and the health of one part directly impacts the whole. The idea of rivers as living networks, rather than just channels for water, is a perfect metaphor for the intricate web of life on Earth.
While out on many river's in my lifetime, it's not lost on me that the flow connects mountain streams to sprawling deltas, nourishing the land and all its inhabitants along the way, our own lives are part of a continuous cycle of connection.
I like to think when we mistakenly see a river as a singular, isolated entity, we fail to recognize the myriad of relationships that define its existence. Remembering the insects that feed the fish, the birds that nest in the trees on its banks, the groundwater that sustains it even in drought. It's now more than ever important to teach the concepts of the circle of life in its truest form: an endless loop of give and take.
I hate that when we disrupt this cycle by damming, dredging, or polluting rivers, we do more than just alter their physical course. We failed with our Corps of Engineers in our human efforts break what is natural to suit our own need to conquer and harness bodies of water.
We certainly didn't understand the consequences when we severed the links between species and ecosystems, leading to a loss of resilience and an inability for the system to recover.
Similarly, when we fail to nurture our own connections to the world around us—to other people, to animals, to the natural environment—we weaken our own collective strength. We lose the ability to adapt and thrive together.
Your call to "share the love for healthy, functioning rivers" is therefore not just about conservation; it's an invitation to acknowledge our place within this grand, interconnected network. By working to restore and protect these living arteries of our planet, we are also nurturing our own connections to all creatures.
I find your in-depth explanations refreshing and a very worthwhile. Looking forward to your next post on this important topic.
Wow -- how beautifully said! Thanks for your thoughtful comment. I don't want to say much in response as your thoughts are bang on and speak for themselves! Thanks! :)
River networks in the framework of complex network theory
https://link.aps.org/doi/10.1103/kpbq-8wzb
Thanks for sharing
Wow this is a completely new perspective on two of my favourite things. Rivers and trees are connected in so many beautiful ways and both give life. Thank you for writing this.
Thanks. Glad you enjoyed it.
Inspiring and mind-expanding, thank you Jonathan. I guess you will have come across the wonderful new(ish) book Is A River Alive? by Robert MacFarlane (https://www.penguin.co.uk/books/455147/is-a-river-alive-by-macfarlane-robert/9780241624814), I greatly enjoyed it.
Thanks Nigel! Happy to expand minds! :) Yes, I've come across it but not read it yet. I need to get myself a copy.
I’d love to understand more about the interaction between groundwater and rivers. Three rivers meet in my village. Two are part of a hydro power scheme so the flows a partially controlled. The third is a classic gravel bed river, draining mountains and braiding among shifting islands on its floodplain (where the village stands!). It is prone to flash flooding because the hills are denuded of trees through centuries of sheep farming and now hundreds of red deer.
A new pattern has emerged in recent years that has been particularly striking and long lasting - all the feeder springs, streams and ditches dried up in the spring and are waterless. The groundwater level seems to have sunk deeper below the surface into the alluvial gravels below our feet.
That's not good to hear. Could be a signal of climate change or mismanagement by the hydro scheme or just over-extraction of the groundwater for drinking. Are they glacial fed? But yes, sounds like groundwater depletion.
I loved reading about how important rivers are and their relationship with all manner of species. I guess it's hard for a lot of people to understand what they can't physically see. They just see water or perhaps some fish. Wouldn't this topic make a great Television series! You should team up with David Attenborough! Your explanations are spot on and I'll look forward to reading more.
Thanks Kim! Yes, can someone please reach out to David for me! 🤣 How cool would that be!! Revealing the wonders of rivers. 😇
I love this! Fascinating and informative. 😊
Thanks very much!
When you mentioned "hierarchical dendritic networks" I became excited thinking you might dig into self-similarity at varying scales and fractal dimensions. Streams flowing into a river / from a delta and water transpiring up a tree trunk are similar optimisations to achieve economy of energy.
Ha -- yes, I thought I might lose my readers going into that direction too far. But yes rivers networks are fractal. It's fun simulating river networks. There are tools out there for making like easy to do so using Optimal Channel Networks.
This is a fantastic post, Jonathan, and such a needed reminder that rivers are more than linear systems. One key oversight I have always found in the River Continuum Concept is how little attention springs received in that framework. Headwaters, which form the foundation of the continuum, are for the most part spring fed. The unique ecological signatures we see in headwater streams, from stable thermal regimes to highly endemic invertebrate communities, are in large part driven by the influence of springs.
Without springs, most rivers globally would be ephemeral. Their constant discharge underpins the hydrologic stability that makes perennial rivers possible in the first place. Beyond hydrology, springs also shape biodiversity patterns: they introduce heterogeneity across headwater habitats, creating the mosaic of community compositions that ultimately scale up to the network level diversity you describe here. Of course, there are exceptions such as in ice dominated watersheds, but across most of the globe springs remain the primary source.
If we are rethinking rivers as networks, then springs should be recognized as the nodes where rivers are literally born, places that drive both ecological resilience and biogeographic uniqueness.
Let me know if this interests you and we could discuss more. I think its worthy of a manuscript.
Thanks Joseph! Absolutely a topic of interest. Much of my PhD was spent looking for spring-fed streams as I was interested in the role of habitat stability on diversity. Happy to chat more!
I actually have a review paper in review right now about the role of extreme events on river biodiversity and have realised I don't touch on the importance of springs as refuges so might try to sneak that into the final section after the next round of review.
Story first, then the question.
I was up in northern Maine (south branch pond area) during the tail end of this years droughty conditions. I didn’t want to filter warm pond water if I didn’t have to cause I like cold water / ideally spring water. I had time and it was rediculously hot and humid so I kayaked over to the largest inlet drainage and I walked up a dry cobble gravel stream bed for about 10 minutes (1/2 mile).
Eventually I saw pools with stranded but seemingly happy (fast moving) trout and finally a couple hundred yards upstream I found a continuous section of “gaining stream” with ~55 degree F ground water to filter and drink.
I mentioned this to the ranger in passing when I inquired about the fishing rules and he said walk down the outlet stream and you’ll find the same thing.
What I would be super interested in is how trout, insects, etc utilize the river bed morphology and substrate for shelter during intermittent high peak flow conditions that break the drought.
Are they taking refuge in the deep pools? Is there an edge effect they are also taking advantage of? Do they just bury themselves in between the cobbles? Where do they find refuge during the transitional condition my story is about?
Good question. Depends on the species entirely.
Trout would mostly move to spots where there are back-eddies etc. where the flow is slack. Mostly likely along the margins. Some fish burrow into the substrate, but depends on the river. In NZ, we have very dynamic rivers and many of our natives will burrow several metres under the substrate because there's a whole bunch of large cobbles with lots of interstitial spaces between them. Invertebrates, again species specific. Some just hold on (they're quite flattened in form), some have silk attachments that stops them drifting, some burrow etc.
Finally, if these high flows are predictable, they may be triggers for a life-cycle event like spawning, migration etc. In NZ some of our native fish lay their eggs in river margins above the water line waiting for a high-flow event to wash their eggs or larvae out to sea for juvenile rearing.
Thank you! Fish laying eggs above water line is something I would have never believed possible.
No worries!
This moved me powerfully!!!!!! Can't wait for the fourth dimension of time. Wow.
Thanks so much, Stephanie! Glad you liked it.