̽��ֱ�� of Cambridge - ecology

No evidence that England’s new ‘biodiversity boost’ planning policy will help birds or butterflies

jg533 — Fri, 28 Jun 2024 04:01:30 +0000

From 2024, the UK’s Environment Act requires planning applications to demonstrate an overall biodiversity net gain of at least 10% as calculated using a new statutory biodiversity metric.

̽��ֱ��researchers trialled the metric by using it to calculate the biodiversity value of 24 sites across England. These sites have all been monitored over the long-term, allowing the team to compare biodiversity species data with results from the metric.

Plant biodiversity at the sites matched values produced using the metric, but bird and butterfly biodiversity did not.

This means there’s no evidence that a 10% net biodiversity gain calculated using the statutory biodiversity metric will translate into real-life gains for birds and butterflies, without additional conservation management.

This is the first comprehensive study of the performance of Defra’s statutory biodiversity metric across England. ̽��ֱ��results were published on 28 June in the Journal of Applied Ecology.

Plants, birds and butterflies have been comprehensively surveyed in England over many years, and are used as indicators for the national state of nature.

̽��ֱ��researchers say the metric must be improved to better capture the intricacies of the different species within an ecosystem.

“ ̽��ֱ��statutory biodiversity metric is a really important opportunity, and has potential to direct a lot of money into biodiversity conservation from developers. It’s the responsibility of conservationists and policy makers to ensure that it provides a reliable indication of nature’s diversity,” said Dr Cicely Marshall in the ̽��ֱ�� of Cambridge’s Department of Plant Sciences, first author of the paper.

She added: “At the moment the metric does capture plant diversity quite well, but it doesn’t reflect the intricacies of ecosystems – species like birds and butterflies use habitats in very different ways.”

̽��ֱ��metric, created by the UK Government’s Department for Environment, Food and Rural Affairs (Defra), was introduced as part of the Environment Act with its legally binding agenda to deliver “the most ambitious environmental programme of any country on earth.” It scores the condition and distinctiveness of a piece of land to calculate its biodiversity value in standardised ‘biodiversity units.’

This allows developers to project biodiversity losses and gains across a site, so they can ensure the development achieves an overall minimum 10% biodiversity gain. Landowners can use the tool to calculate the biodiversity value of their land.

Marshall, who is also a Research Fellow at King’s College, Cambridge, said: “Many property developments have been very detrimental to nature in the past, and it’s exciting that England now has a requirement for developers to leave nature in a better state than they found it.

“We hope our study will contribute to improving the way nature’s value is calculated, to make the most of this valuable opportunity for nature recovery.”

̽��ֱ��results of the study have been used to make recommendations to Defra and Natural England to help improve the metric.

̽��ֱ��metric uses habitat as a proxy for biodiversity, scoring habitats’ intrinsic distinctiveness and current condition. Plans for biodiversity gain can involve replacing lost habitat with similar habitat - the researchers say that nature recovery could be improved if the particular species and habitats impacted by a development were also taken into account in this process.

There can be huge differences in biodiversity across habitats like croplands, for example, and these aren’t captured by the metric which assigns all cropland the same condition score. Conventional farms that regularly use artificial pesticides and herbicides have much lower biodiversity than organic farms that do not.

“There are great differences in the ecological value of cropland depending on how it’s managed, but the metric gives all cropland a low biodiversity score. It would be nice to see these differences reflected,” said Marshall.

̽��ֱ��UK is committed to building 300,000 homes a year by mid-2020, so the net biodiversity gain requirement is expected to generate a market for biodiversity credits worth an estimated £135m-£274m annually – substantially increasing funding for nature conservation in England.

̽��ֱ��research was funded by the Ecological Continuity Trust.

Reference: Marshall, C. 'England’s statutory biodiversity metric enhances plant, but not bird nor butterfly biodiversity'. Journal of Applied Ecology, June 2024. DOI: 10.1111/1365-2664.14697

A new legal requirement for developers to demonstrate a biodiversity boost in planning applications could make a more meaningful impact on nature recovery if improvements are made to the way nature’s value is calculated, say researchers at the ̽��ֱ�� of Cambridge.

We hope our study will contribute to improving the way nature’s value is calculated, to make the most of this valuable opportunity for nature recovery.

Cicely Marshall

Researchers assess woodland condition at Alice Holt Forest

̽��ֱ��text in this work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. Images, including our videos, are Copyright © ̽��ֱ�� of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – on our main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms.

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Licence type:

Attribution-Noncommerical

Phone-based measurements provide fast, accurate information about the health of forests

sc604 — Tue, 07 Mar 2023 01:21:40 +0000

̽��ֱ��researchers, from the ̽��ֱ�� of Cambridge, developed the algorithm, which gives an accurate measurement of tree diameter, an important measurement used by scientists to monitor forest health and levels of carbon sequestration.

̽��ֱ��algorithm uses low-cost, low-resolution LiDAR sensors that are incorporated into many mobile phones, and provides results that are just as accurate, but much faster, than manual measurement techniques. ̽��ֱ��results are reported in the journal Remote Sensing.

̽��ֱ��primary manual measurement used in forest ecology is tree diameter at chest height. These measurements are used to make determinations about the health of trees and the wider forest ecosystem, as well as how much carbon is being sequestered.

While this method is reliable, since the measurements are taken from the ground, tree by tree, the method is time-consuming. In addition, human error can lead to variations in measurements.

“When you’re trying to figure out how much carbon a forest is sequestering, these ground-based measurements are hugely valuable, but also time-consuming,” said first author Amelia Holcomb from Cambridge’s Department of Computer Science and Technology. “We wanted to know whether we could automate this process.”

Some aspects of forest measurement can be carried out using expensive special-purpose LiDAR sensors, but Holcomb and her colleagues wanted to determine whether these measurements could be taken using cheaper, lower-resolution sensors, of the type that are used in some mobile phones for augmented reality applications.

Other researchers have carried out some forest measurement studies using this type of sensor, however, this has been focused on highly-managed forests where trees are straight, evenly spaced and undergrowth is regularly cleared. Holcomb and her colleagues wanted to test whether these sensors could return accurate results for non-managed forests quickly, automatically, and in a single image.

“We wanted to develop an algorithm that could be used in more natural forests, and that could deal with things like low-hanging branches, or trees with natural irregularities,” said Holcomb.

̽��ֱ��researchers designed an algorithm that uses a smartphone LiDAR sensor to estimate trunk diameter automatically from a single image in realistic field conditions. ̽��ֱ��algorithm was incorporated into a custom-built app for an Android smartphone and is able to return results in near real time.

To develop the algorithm, the researchers first collected their own dataset by measuring trees manually and taking pictures. Using image processing and computer vision techniques, they were able to train the algorithm to differentiate trunks from large branches, determine which direction trees were leaning in, and other information that could help it refine the information about forests.

̽��ֱ��researchers tested the app in three different forests – one each in the UK, US and Canada – in spring, summer and autumn. ̽��ֱ��app was able to detect 100% of tree trunks and had a mean error rate of 8%, which is comparable to the error rate when measuring by hand. However, the app sped up the process significantly and was about four and a half times faster than measuring trees manually.

“I was surprised the app works as well as it does,” said Holcomb. “Sometimes I like to challenge it with a particularly crowded bit of forest, or a particularly oddly-shaped tree, and I think there’s no way it will get it right, but it does.”

Since their measurement tool requires no specialised training and uses sensors that are already incorporated into an increasing number of phones, the researchers say that it could be an accurate, low-cost tool for forest measurement, even in complex forest conditions.

̽��ֱ��researchers plan to make their app publicly available for Android phones later this spring.

̽��ֱ��research was supported in part by the David Cheriton Graduate Scholarship, the Canadian National Research Council, and the Harding Distinguished Postgraduate Scholarship.

Reference:
Amelia Holcomb, Linzhe Tong, and Srinivasan Keshav. ‘Robust Single-Image Tree Diameter Estimation with Mobile Phones.’ Remote Sensing (2023). DOI: 10.3390/rs15030772

Researchers have developed an algorithm that uses computer vision techniques to accurately measure trees almost five times faster than traditional, manual methods.

Ground-based measurements are hugely valuable, but also time-consuming. We wanted to know whether we could automate this process.

Amelia Holcomb

Baac3nes via Getty Images

Treetops seen from a low angle

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. Images, including our videos, are Copyright © ̽��ֱ�� of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – as here, on our main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms.

Yes

‘Antisocial’ damselfish are scaring off cleaner fish customers – and this could contribute to coral reef breakdown

cg605 — Thu, 23 Feb 2023 09:00:35 +0000

̽��ֱ��meal of choice for the Caribbean cleaner fish, the sharknose goby, is a platter of parasites, dead tissue, scales and mucus picked off the bodies of other fishes. By removing these morsels, gobies are offering their ‘cleaning services’ to other marine life – a famous example of a mutually beneficial relationship between species.

But new research from the ̽��ֱ�� of Cambridge and Cardiff ̽��ֱ�� shows that when gobies inadvertently set up shop within the territories of aggressive damselfish, damselfish scare off the gobies’ ‘choosy client customers’.

̽��ֱ��study, published today in Behavioral Ecology, is an example of a largely unexplored phenomenon: a mutually beneficial relationship in nature being disrupted by a third party.

Sharknose gobies work solo or band together and set up a ‘cleaning station’: a fixed location in a particular nook of coral reef, where other marine life burdened by parasites go to take advantage of the gobies’ dietary needs.

“Gobies wait at cleaning stations for customers to visit, similar to shops. And with customers, come the parasites,” said Dr Katie Dunkley, a behavioural ecologist at the ̽��ֱ�� of Cambridge’s Department of Zoology. “In return for providing a cleaning service the gobies receive a payment of food.”

Customers are varied and include parrotfish, surgeonfish and butterflyfish. These choosy client fish shop around, visiting different cleaning stations open for business. If interested, they will adopt a stationary pose that makes a clean more likely – typically a head or tail-stand position with all fins flared.

During a clean – which could last from a few seconds to several minutes – gobies make physical contact with the customer, removing parasites and other dead body tissue. This is known as ‘tactile stimulation’ and, as well as getting rid of parasites, it may act as a massage reducing the customer’s stress, says Dunkley. Previous research has established the importance of cleaners – their removal led to fewer numbers and less variety of fish species on reefs.

“Cleaning stations act as a marketplace, and if customers stop showing up, over time a cleaning station is going to go out of business,” said Dunkley.

Five researchers spent over 34 hours observing cleaning stations on a shallow fringing reef in Tobago over a period of six weeks. Equipped with snorkels and waterproof paper they recorded underwater interactions for 10-minute periods from 8am-5:15pm each day.

They found that client fish were less likely to go to cleaning stations that were more often patrolled by damselfish, who scared ‘intruders’ away.

“I thought that damselfish might play a role as they visit cleaning stations too – although don’t often get cleaned – but to see just how influential they were was startling.

“Damselfish act like farmers as they weed out algae they don’t want, to encourage their preferred algae to grow. Damselfish are protective over their algal territories, and these antisocial fish spend a lot of time patrolling their territories, scaring away intruders through biting, attacking, chasing or threatening displays.”

Damselfish’s territories cover up to 70% of some reefs. On a healthy coral reef, a balance is maintained between algae and coral. But as reefs deteriorate and overfishing intensifies, algae thrive. As reefs deteriorate damselfish may become more common and/or aggressive – leading to fewer species receiving the goby cleaning treatment needed to keep them healthy, says Dunkley. This could ultimately contribute to the breakdown of delicate ecosystems supported by reefs.

“In future we’d like to tease out the motives of damselfish. Are they driven by wanting to protect their algae farms or monopolise cleaning stations?” said Dunkley, a Charles Darwin and Galapagos Islands Fund Junior Research Fellow at Christ’s College, Cambridge.

“Just as humans are connected through family, friends and colleagues, all fish are connected to each other. It’s important that we don’t just look at relationships in isolated bubbles. We need to step back and see how all fish are connected so that we can protect ecosystems like coral reefs.”

̽��ֱ��study was funded by a Natural Environment Research Council GW4+ studentship and Christ’s College ̽��ֱ�� of Cambridge Galapagos Islands Fund (both awarded to first author, Katie Dunkley). Last author, James Herbert-Read, was supported by the Whitten Lectureship in Marine Biology, and a Swedish Research Council Grant (2018–04076).

Dunkley et al, ̽��ֱ��presence of territorial damselfish predicts choosy client species richness at cleaning stations, Behavioral Ecology, DOI: doi.org/10.1093/beheco/arac122

Damselfish have been discovered to disrupt ‘cleaning services’ vital to the health of reefs. And climate change may mean this is only likely to get worse.

"We need to step back and see how all fish are connected so that we can protect ecosystems like coral reefs."

Dr Katie Dunkley

Secrets of the reef revealed

Federica Grassi / Moment via Getty Images

Yes

Dense bones allowed Spinosaurus to hunt underwater

sc604 — Wed, 23 Mar 2022 15:39:48 +0000

Spinosaurus is the biggest carnivorous dinosaur ever discovered—even bigger than T. rex—but the way it hunted has been a subject of debate for decades. Based on its skeleton, some scientists have proposed that Spinosaurus could swim, but others believe that it waded in the water like a heron.

To help solve this mystery, palaeontologists from the Universities of Cambridge and Oxford, and the Field Museum in Chicago, USA, have taken a different approach by examining the density of their bones and comparing them to animals like penguins, hippos and alligators.

̽��ֱ��team’s analysis, published in the journal Nature, found that Spinosaurus and its close relative Baryonyx had dense bones that likely would have allowed them to submerge themselves underwater to hunt. Meanwhile, another related dinosaur called Suchomimus had lighter bones that would have made swimming more difficult, so it likely waded instead or spent more time on land like other dinosaurs.

“ ̽��ֱ��fossil record is tricky — there are only a handful of partial spinosaurid skeletons, and we don’t have any complete skeletons for these dinosaurs,” said co-lead author Dr Matteo Fabbri from the Field Museum. “Other studies have focused on interpretation of anatomy, but if there are such opposite interpretations regarding the same bones, this is already a clear signal that maybe those are not the best proxies for us to infer the ecology of extinct animals.”

“There’s nothing like Spinosaurus in our modern world, but they had a number of traits that we see today in semi-aquatic animals who specialise in aquatic prey,” said co-lead author Dr Guillermo Navalón from Cambridge’s Department of Earth Sciences.

All life initially came from water, and most groups of terrestrial vertebrates contain members that have returned to it—for instance, while most mammals are land-dwellers, we’ve got whales and seals that live in the ocean, and other mammals like otters, tapirs, and hippos that are semi-aquatic. For a long time, non-avian dinosaurs (those that didn’t branch off into birds) were the only group without any water-dwellers. That changed in 2014, when a new Spinosaurus skeleton was described.

Scientists already knew that spinosaurids spent some time by water—their long, crocodile-like jaws and cone-shaped teeth are like those of other aquatic predators, and some fossils had been found with bellies full of fish. But the Spinosaurus specimen described in 2014 had retracted nostrils, short hind legs, paddle-like feet, and a fin-like tail: all signs that pointed to an aquatic lifestyle. But researchers have continued to debate whether spinosaurids swam for their food or if they just stood in the shallows and dipped their heads in to snap up prey.

This continued back-and-forth led the researchers to try to find another way to solve the problem.

“Instead of trying to know as much as possible about the whole skeleton of Spinosaurus, we asked a much simpler question — what are the most important small-scale observations that would tell you whether animals routinely swim or not?” said co-lead author Professor Roger Benson from the ̽��ֱ�� of Oxford.

Across the animal kingdom, bone density is a tell in terms of whether that animal can sink beneath the surface and swim. Dense bone works as buoyancy control and allows the animal to submerge itself.

“We thought maybe this is the proxy we can use to determine if spinosaurids were actually aquatic,” says Fabbri.

̽��ֱ��researchers put together a dataset of femur and rib bone cross-sections from 250 species of extinct and living animals, from seals, whales, elephants, mice and hummingbirds, to dinosaurs of different sizes, to extinct marine reptiles like mosasaurs and plesiosaurs.

They compared these cross-sections to bone from Spinosaurus and its relatives Baryonyx and Suchomimus. “We had to divide this study into successive steps,” said Navalón. “ ̽��ֱ��first was to understand if there is actually a universal correlation between bone density and ecology. And the second was to infer ecological adaptations in extinct taxa.”

Essentially, the team had to show a proof of concept among present-day animals that we know for sure are aquatic or not, and then apply it to extinct animals that we can’t observe.

̽��ֱ��study revealed a clear link between bone density and aquatic foraging behaviour: animals that submerge themselves underwater to find food have bones that are almost completely solid throughout, whereas cross-sections of land-dwellers’ bones look more like doughnuts, with hollow centres.

“Aquatic animals need to be able to control their buoyancy, but terrestrial animals don't have this problem,” said Navalón. “Because bones are mineralised tissue, controlling the rate of deposition of mineralised tissue within them is the easiest route to become denser or lighter for a land-dwelling vertebrate. This happened in many groups that underwent the ‘back to water’ evolutionary journey: from whales and hippopotamuses to penguins and marine reptiles that lived in the distant past.”

When the researchers applied spinosaurid dinosaur bones to this paradigm, they found that Spinosaurus and Baryonyx both had the sort of dense bone associated with full submersion.

“If we combine all these pieces of evidence, Spinosaurus might have moved through shallow water using a combination of ‘bottom-walking’ – like modern hippos – and side-to-side strokes of its giant tail,” said Navalón. “It probably used this means of locomotion not to pursue prey for long distances in open water, but to ambush and catch very large fish like lungfishes or coelacanths that lived in the same environment.”

Meanwhile, the closely-related Suchomimus had hollower bones. It still lived by water and ate fish, as evidenced by its crocodile-mimic snout and conical teeth, but based on its bone density, it wasn’t actually swimming.

Other dinosaurs, like the giant long-necked sauropods also had dense bones, but the researchers don’t think that meant they were swimming. “Very heavy animals like elephants and rhinos, and like the sauropod dinosaurs, have very dense limb bones, because there’s so much stress on the limbs,” said Fabbri. “ ̽��ֱ��other bones are pretty lightweight. That’s why it was important for us to look at a variety of bones from each of the animals in the study.” And while there are limitations to this kind of analysis, there is potential for this study to tell us about how dinosaurs lived.

“One of the big surprises from this study was how rare underwater foraging was for dinosaurs, and that even among spinosaurids, their behaviour was much more diverse that we’d thought,” said Navalón.

̽��ֱ��study shows how much information can be gleaned from incomplete specimens. “ ̽��ֱ��good news with this study is that now we can move on from the paradigm where you need to know as much as you can about the anatomy of a dinosaur to know about its ecology, because we show that there are other reliable proxies that you can use,” said Fabbri.

Reference:
Matteo Fabbri, Guillermo Navalón, Roger B J Benson et al. ‘Subaqueous foraging among carnivorous dinosaurs.’ Nature (2022). DOI: 10.1038/s41586-022-04528-0

Adapted from a Field Museum press release.

Its close cousin Baryonyx probably swam too, but Suchomimus might have waded like a heron.

There’s nothing like Spinosaurus in our modern world, but they had a number of traits that we see today in semi-aquatic animals who specialise in aquatic prey

Guillermo Navalón

Davide Bonadonna

Spinosaurus

Yes

Butterflies through time: a new exhibition

lkm37 — Tue, 22 Mar 2022 09:39:18 +0000

Butterflies through time at Cambridge’s Museum of Zoology illuminates the beautiful, turbulent history of butterflies across the UK.

UK plants flowering a month earlier due to climate change

sc604 — Wed, 02 Feb 2022 00:08:32 +0000

Using a citizen science database with records going back to the mid-18th century, a research team led by the ̽��ֱ�� of Cambridge has found that the effects of climate change are causing plants in the UK to flower one month earlier under recent global warming.

̽��ֱ��researchers based their analysis on more than 400,000 observations of 406 plant species from Nature’s Calendar, maintained by the Woodland Trust, and collated the first flowering dates with instrumental temperature measurements.

They found that the average first flowering date from 1987 to 2019 is a full month earlier than the average first flowering date from 1753 to 1986. ̽��ֱ��same period coincides with accelerating global warming caused by human activities. ̽��ֱ��results are reported in Proceedings of the Royal Society B.

While the first spring flowers are always a welcome sight, this earlier flowering can have consequences for the UK’s ecosystems and agriculture. Other species that synchronise their migration or hibernation can be left without the flowers and plants they rely on – a phenomenon known as ecological mismatch – which can lead to biodiversity loss if populations cannot adapt quickly enough.

̽��ֱ��change can also have consequences for farmers and gardeners. If fruit trees, for example, flower early following a mild winter, entire crops can be killed off if the blossoms are then hit by a late frost.

While we can see the effects of climate change through extreme weather events and increasing climate variability, the long-term effects of climate change on ecosystems are more subtle and are therefore difficult to recognise and quantify.

“We can use a wide range of environmental datasets to see how climate change is affecting different species, but most records we have only consider one or a handful of species in a relatively small area,” said Professor Ulf Büntgen from Cambridge’s Department of Geography, the study’s lead author. “To really understand what climate change is doing to our world, we need much larger datasets that look at whole ecosystems over a long period of time.”

̽��ֱ��UK has such a dataset: since the 18th century, observations of seasonal change have been recorded by scientists, naturalists, amateur and professional gardeners, as well as organisations such as the Royal Meteorological Society. In 2000, the Woodland Trust joined forced with the Centre for Ecology & Hydrology and collated these records into Nature’s Calendar, which currently has around 3.5 million records going back to 1736.

“Anyone in the UK can submit a record to Nature’s Calendar, by logging their observations of plants and wildlife,” said Büntgen. “It’s an incredibly rich and varied data source, and alongside temperature records, we can use it to quantify how climate change is affecting the functioning of various ecosystem components across the UK.”

For the current study, the researchers used over 400,000 records from Nature’s Calendar to study changes in 406 flowering plant species in the UK, between 1753 and 2019. They used observations of the first flowering date of trees, shrubs, herbs and climbers, in locations from the Channel Islands to Shetland, and from Northern Ireland to Suffolk.

̽��ֱ��researchers classified the observations in various ways: by location, elevation, and whether they were from urban or rural areas. ̽��ֱ��first flowering dates were then compared with monthly climate records.

To better balance the number of observations, the researchers divided the full dataset into records until 1986, and from 1987 onwards. ̽��ֱ��average first flowering advanced by a full month, and is strongly correlated with rising global temperatures.

“ ̽��ֱ��results are truly alarming, because of the ecological risks associated with earlier flowering times,” said Büntgen. “When plants flower too early, a late frost can kill them – a phenomenon that most gardeners will have experienced at some point. But the even bigger risk is ecological mismatch. Plants, insects, birds and other wildlife have co-evolved to a point that they’re synchronised in their development stages. A certain plant flowers, it attracts a particular type of insect, which attracts a particular type of bird, and so on. But if one component responds faster than the others, there’s a risk that they’ll be out of synch, which can lead species to collapse if they can’t adapt quickly enough.”

Büntgen says that if global temperatures continue to increase at their current rate, spring in the UK could eventually start in February. However, many of the species that our forests, gardens and farms rely on could experience serious problems given the rapid pace of change.

“Continued monitoring is necessary to ensure that we better understand the consequences of a changing climate,” said co-author Professor Tim Sparks from Cambridge’s Department of Zoology. “Contributing records to Nature’s Calendar is an activity that everyone can engage in.”

̽��ֱ��research was supported in part by the European Research Council, the Fritz and Elisabeth Schweingruber Foundation, and the Woodland Trust.

Reference:
Ulf Büntgen et al. ‘Plants in the UK flower a month earlier under recent warming.’ Proceedings of the Royal Society B (2022). DOI: 10.1098/rspb.2021.2456

Climate change is causing plants in the UK to flower a month earlier on average, which could have profound consequences for wildlife, agriculture and gardeners.

To really understand what climate change is doing to our world, we need much larger datasets that look at whole ecosystems over a long period of time

Ulf Büntgen

Crab apple tree in bloom

Yes

Transcribing together

zs332 — Fri, 23 Jul 2021 09:27:10 +0000

Volunteers join together to help the Cambridge Digital Library transcribe the notebooks of notable British ecologist, Oliver Rackham.

Museum of Zoology displays ceramic art to explore Earth's 'breaking points'

ta385 — Wed, 21 Jul 2021 06:00:00 +0000

̽��ֱ��museum's reopening exhibition uses the fragility of fired clay to throw attention back on to ecological decline, ecosystem collapse and environmental change