What is an allergic reaction?  And how might wood smoke cause it?(Hayley)

An allergic reaction according to the medical dictionary is ‘A local or generalized reaction of an organism to internal or external contact with a specific allergen to which the organism has been previously sensitized.’ Allergies can include such things as animal fur, dust, food types and penicillin to name a few.

An allergic reaction can occur when through exposure to antigens enter the body through the mouth, noes, eyes or even through the skin. The immune system mistakes the harmless allergens as threats and the process of phagocytosis begins. The T cells produce proteins (antibodies) specific to the allergens. Antibodies then attach to the other immune cells causing them to be more sensitive to this particular allergen. The immune cells attack and histamine is produced causing the physiological effects such as redness swelling, sores, itching and sneezing. The worst type of an allergic reaction is anaphylaxis. This is where the allergic reaction causes the tongue to swell and the wind pipe to constrict causing difficulty breathing this can be treated with an epi-pen containing adrenaline which can be a lifesaver.

Wood smoke is made up of carbon monoxide, benzene and sulphur dioxide to name but a few. This wood smoke effects up to 2% of the population causing them to have an allergic reaction. The allergic reaction Is actually caused by chemicals called quinones which are produced to protect the tree from fungi and predators. These quinones bind to skin proteins and because they are foreign to the body they are then attacked by the immune system causing the symptoms above.

Not the are you at risk of allergies from wood smoke but the tiny particulate matter 1/20^th the size of a raindrop is most harmful especially within young children and the elderly. Inhaling these particles into the lungs increases the likelihood of respiratory problems such as asthma, emphysema and bronchitis reducing life expectancy.

Sources Used

http://www.youtube.com/watch?v=y3bOgdvV-_M

http://www.nhs.uk/Conditions/Allergies/Pages/Symptoms.aspx

http://burningissues.org/pdfs/WoodSmBroharris.pdf

Is high biodiversity always the best thing?

“Biodiversity within particular populations and habitats may be very important for their continued success and survival in the face of both competition and disease.” (Thomas, P. and Packham, J. 2007)

High biodiversity is beneficial within habitats and also for humans. I will talk about a couple of examples.

In a habitat, high biodiversity can allow species to survive diseases, because if there is a lot of variation in the genetic make-up of a species in a habitat, and the area is affected by disease, the genetic diversity gives at least some of the specimens a chance to survive and reproduce. Therefore, the level of biodiversity in a habitat can depend on the history of the area.

Another advantage of a high level of biodiversity it that it is likely that all niches in the habitat will be filled, thus reducing the chance of an invasive alien species filling a niche and destabilising the environment through introducing new pests, and competing for food, space and sunlight. Sometimes, different species in a habitat can form symbiotic relationships, resulting in benefits for both species and consequently the habitat can be more stable.

High biodiversity is also an advantage for humans and society. Humans have an enormous variety of uses for plant and animal resources.

It is widely known that there are many species that are yet to be discovered, which may, for example, provide a breakthrough in treatment of an illness that as yet we have no cure for. If there was a reduction in biodiversity, the balance of environments may be disrupted, resulting in species changing, or dying out in a particular area.  A loss in high biodiversity would negatively impact society as it may result in the loss of resources, medicines, food and nutrition, whether directly or indirectly.

From this I have concluded that a high level of biodiversity is a good thing!

I found these resources useful when thinking about biodiversity:

http://www.who.int/globalchange/ecosystems/biodiversity/en/index.html

http://www.cnr.uidaho.edu/veg_measure/Modules/Lessons/Module%207/7_2_Biodiversity.htm

Thomas, P. and Packham, J. (2007) Ecology of Woodlands and Forests. Cambridge: Cambridge University Press

(Zoe)

A Day in the Woods with Year 2 Red Class (Hayley)

Before the day in the forest began I was a little bit nervous I was unsure of how being outside would change the way the children behaved as the setting was unusual to them. I was also unsure about what level I was going to be expected to try and teach the children at because I have never worked within a year two class. However, I was extremely excited about getting the chance to put all that we had learned with in the forest into practice and to ensure every child had a fantastic day.



The day started in the brilliant sunshine and with a magical entrance from the Reeve explaining the challenges the day would bring. My nerves were settled almost at once after meeting the class they were all fabulous. Immediately, I could see the excitement in the children’s eyes as they set off on the fairy trail which led them straight to the fire circle. Here I helped with the dying activity by supervising the group crushing berries. Next, they all had to write words to help them later with telling their own stories. During this activity I noticed a little boy was very withdrawn. After sitting down next to him I discovered he was not a confident writer, in order to stop him feeling left out I encouraged him to describe to me some words then asked if he would like to draw them instead.



Throughout the day I also helped out with some shelter building which the kids loved. It gave them the freedom to create their own little dens choosing their own materials so they could eat their lunches inside. It was great to see all of the parents getting involved in some cases I wasn’t sure who was having more fun them or the children. I also helped the children at the end of the day to create their own little fires this was important to ensure the children were all kept safe.



Jess and I chose to show the children how they could cook cakes in orange skins to lead them into talking about irreversible and reversible changes. This was completely different to our original plan which was to cook eggs within the oranges but one of our class mates told us how she had done it with cakes in brownies and we thought the children would enjoy this activity more any might actually taste them. To get the children talking about chemical changes we first asked the children what they thought was in the cake mixture. The next step was to ask them after we had heated the mixture on the fire. Most of the children were able to say that they wouldn’t be able to get the original materials back and some were able to tell me why we used certain ingredients such as self-raising flour to help the cake rise. I also tried to give them examples of things that were reversible such as water to ice but the seamed to find this harder to understand.



Our activity was extremely hands on we asked the children to scrape the insides of the oranges out. Whilst some children really enjoyed getting messy and pulling the insides out others did not. We took a mixed group of boys and girls, which worked really well as the boys helped out the girls with the messy bit that they didn’t want to do. They then mixed up the cake mix and poured it into the orange skins which were then placed on a baking tray onto the fire.



During our activity we did have a few problems some of which we were able to address along the way. The 1^st problem that we noticed was we were filling the orange skins too much so the cakes were rising and spilling out onto the tray. We also notices some of the cakes were still soggy after coming off the fire, this was addressed by ensuring the last group to scoop out their oranges took all of the insides out leaving no residue. Looking back on the activity we needed a practice run ourselves so we could have addressed these problems earlier. I also noticed some of the children found scooping out the oranges hard it may have been an idea to first cut round the orange skins to make it simpler for them. I would not have pre-scooped the oranges to as the children really enjoyed the chance to get messy. Overall, I feel our activity went well as all the children appeared to have fun and learn a little about the science behind the irreversible changes occurring in front of their eyes. I would definitely take classes out for a day of science in the woods again!

The Importance of Indicator Species

Indicator Species

The presence, absence or relative abundance of indicator species reflects environmental conditions; therefore they can be used as a management tool for early warning signs of disruptions to a habitat or ecosystem. Whilst mapping can give an indication of changes in a habitat or ecosystem, observing indicator species can show the impact of these changes over time.

Examples of Indicator Species

In certain wetlands, wood frogs depend on vernal pools, which are free of predators yet are becoming increasingly threatened by changes such as pollution, deforestation and even climate change. Studying these frogs allows scientist to know the health of the wetland ecosystems. If the frogs’ population dwindles, then it is a sign that the health of this wetland ecosystem is suffering, and the scientists can then study the pools further to prevent damage to it.

Other good indicator species include alpine flowers, which offer clues about changing conditions on high peaks; they are at great risk from climate change because they are rare flowers with restricted ranges of where they can grow. By observing when they flower and how long they flower for, scientist can use the species’ life cycles to see if they are beginning to ‘exhibit biological shifts’ (Wroth, 2011). If these shifts are occurring, this could mean that the environment on these high peaks is changing and this change is affecting its ecosystems.

Another example of an indicator species is lichens. Lichens grow in exposed places such as rocks or bark and are very sensitive to sulphur dioxide. They receive their nutrients from the rain water there by absorbing water; therefore air pollutants dissolved in rain water can be very damaging for lichens. If sulphur dioxide is in the air, then lichens could be less abundant or absent from areas where they are normally found. This can suggest to scientists that there is an air pollution problem in that area.

Air pollution is similar to water pollution; many aquatic invertebrate animals cannot survive in polluted waters, so their absence provides scientists with information on how polluted the water is.

Support

To support the study of indicator species, in 1997 Alfaro and Singh discovered that the abundance of invertebrates in a forest canopy is higher in forests which have not been damaged. Therefore, invertebrates are good indicators for showing the health of a forest.

Conclusion

In summary, indicator species is a species or group of species which suggest the health of a habitat or ecosystem; by observing this species, other species which share its ecosystem, those which are also affected by the same threats, or even the ecosystem itself, could be protected for the future.

Emma Barkley, 16^th April

All Accessed 16^th April:

http://www.worldwildlife.org/species/flagship-species.html

http://www.eoearth.org/article/Indicator_species

http://www.outdoors.org/publications/outdoors/2011/features/indicator-species-in-the-northeast.cfm

http://www.epa.gov/bioiweb1/html/indicator.html

http://paypalku.hubpages.com/hub/The-importance-of-role-of-insects-as-indicator-species

http://www.youtube.com/watch?v=xRfdDE6scWA

The impacts of climate change on the South East of England

Climate change is a largely debated issue that is threatening to cause widespread problems across the world. In my earlier blog entry, I briefly mentioned how climate change could impact possible woodland management strategies. But I failed to note how climate change will actually affect the Southern areas of England and what this will mean for woodlands like Seeley Copse, the areas and people surrounding the woodlands.

The BBC state that in the South East of England, on average the temperature will rise 2C by the 2050’s. This will have risen a further 1C 30 years later. However it is not just the heat that will increase but also the rainfall and sea levels will rise, attributed to the melting ice caps. The Climate Research Unit estimate global sea levels will rise between 12cm and 67cm by 2050, possibly causing some areas of the South East to become submerged in water. This problem is further amplified by the fact that the South East of the country is sinking while the North West is rising due to isostatic readjust.

These changes will have many different consequences.

PLANTS and TREES

Overall fifteen per cent of the South East is wooded, this is England’s most wooded region. However with the imminent climate change it is possible this may not be the case in the future.

Scientist believe that the beech tree is likely to be one of the highest risks as the tree’s shallow roots grow on what is normally light, free-draining soil, thus making the tree particularly vulnerable to drought, gales and storms. As a result it is predicted that the beech tree line will recede North and West in line with the temperature changes.

Competition is also likely to occur between different species. This is shown with the oak and the ash when it comes to the first leafing. Oak comes into leaf around 4 days earlier than the ash per every 1C rise in temperature, therefore giving the oak an advantage. With possible future temperature changes it is had to predict the future composition of our woodland.

The change in temperatures will mean that many new plant species will now be able to grow in the South East of England. In gardens more exotic plants and trees may now be found. It is predicted by 2050 that many plants such as delphiniums and lupins could be replaced by pomegranates, citrus fruits and apricots.

Plants will also be affected by the changes in climate as early springs will cause trees and plants to come into life and flower earlier. This may leave less time for the plants to gather energy from the sun for photosynthesis if the trees provide shelter. There will also become an increase in competition for space and light, between traditional spring plants and those that are able to survive harsher conditions.

CROPS and FOOD

The changes in temperatures will alter the types of crops and farming that occurs in the South of England. Two thirds of land is farmed with traditional crops including potatoes, apples and strawberries. The temperature increases could result in the current crops moving northwards with more suited temperatures and the South East growing different crops such as figs, soya and even olives. The fruits found in the region would change with peaches and nectarines soon becoming the norm.

Fishermen will also be changing their catch, soon being able to catch more exotic fish such as mullet, anchovies and even sharks becoming more common in our waters. This will be due to the temperature increase in the seas surrounding the UK.

ANIMALS and INSECTS

The warmer temperatures would cause a wide variety of different insects and pests to thrive that currently cannot. An example worrying many farmers is the Colorado beetle which would cause widespread destruction. A long list of pests may become a problem including; cockroaches, fleas, mites, bloodsucking ticks, scorpions, poisonous spiders and even possibly malaria carrying mosquitoes.

The predicted climate change is putting biodiversity at risk. In the past ten years the number on the governments list of at risk species has doubled from 577 in 1997 to 1,149 in 2007.

On this list a fifth of the UK’s most familiar birds can be found. The future climate changes could put these birds at risk further due to the loss of their natural habitats, breeding habitats and food supply. This may lead to some bird species being lost from the South East and new birds may colonise from Europe.

Added to this list in 2007 was the hedgehog, grass snake and harvest mouse. It is predicted that with future changes the hedgehog may have become extinct by 2025. This will be due to hibernation patterns becoming disrupted and a slug, one of its main food supplies, shortage all caused by the hot dry summers.

Some species will have their life cycles disrupted due to the changes; this will be even more disastrous for species that tend to breed once a year. An example of this already happening is frogspawn. In South East England they are often found even before Christmas and January. This early spawning is caused by the mild weather found in current winters. However problems arise when normal temperatures appear and the water freezes, causing the frogs to have to wait another year in order to breed successfully.

WATER SUPPLIES

Flooding is a major threat posed by climate change this will affect many of the low lying areas of the South of England causing widespread problems for thousands of homes and businesses and industrial areas.

Despite the flooding water is likely to become scarce as the demand is expected to rise by eleven per cent in the next twenty years and as a result water will become expensive. This will cause hosepipe bans to be put into place permanently.

However not all the impacts may be negative. With the increase in temperatures  the Mediterranean is likely to decline as a holiday destination and the South East of England may now become a more suitable alternative with August temperatures predicted to be over 30C. This will bring in large amounts of money for the area if it becomes a tourist hotspot and will increase business. It is also likely to reduce carbon emissions with people moving across the UK rather than using air travel causing airport expansion.

Many of the impacts mentioned to appear to be negative ones, especially for our current wildlife and insect population. However these impacts are not definite outcomes, only predictions currently. Although their may be negative effects there may also be unforeseen benefits with the new climate, and new species may provide benefits that will outweigh the negatives. Until climate change actually occurs it is not possible to say for definite how things will be altered.

Lauren Harden

http://news.bbc.co.uk/1/hi/uk/1015796.stm

http://www.climatechangeandme.net/pages/south_east.html

http://www.climatechangeandme.net/data/files/tomorrows_england_south_east_full_report.pdf

Forest Schools with Year 2: My Day (Jess.S)

The day started bright and early; luckily the weather was in our favour as we loaded the minibus with all the equipment for the day.


Activities for the day started as son as we got there through unloading the minibus, getting our boxes and finding which fire our activities were based at. Myself and Beth were leading the activity on making charcoal - Beth was absent this day but I had help from some of the others who were free for that time slot.


Before activities started I headed over the to car-park with some of the others to meet the children as they departed their coach. The children were all given name stickers to help us when we were leading the activities, then sorted into their groups for the day. Myself and the rest of the 'greeting group' split up so there were a few of us with each group as we headed to the start of the trail where Lauren and Harriet started the days tasks with some decoding.


When the fire safety talk had been given by Duncan - including where to walk and how to kneel while next to the fire. It was time for myself and others to continue with the activities of the day. So we took two of the groups up to another fire circle so we could make some charcoal.


At the beginning of the activity, the children were really enthusiastic and excited about what they would be doing and about where they have seen charcoal be used before. All of the children enjoyed stripping the bark off their pieces of wood; getting ready to turn it into some charcoal they could take away with them.


Once all the stick had been put in the tin and onto the fire, the children had to write down words about the fire and their surroundings. A lot of the children drew pictures to help them with this activity. After a while they started to get bored, which wasn't good - when we planned the lesson we hoped that the charcoal would have been done and so there wouldn't have been time for them to get bored.


To improve this activity in the future I would plan a game or something for the children to play once they had finished with the words and pictures so that they wouldn't be as bored. Apart from that one point, I feel that the activity was successful and the children enjoyed stripping their sticks and drawing the pictures.


At lunchtime I also went with Lauren C to collect any children who wanted to make cakes with Jess or popcorn with Zoe.


I think the whole day was a great success and really showed me how much children can learn even outside of the classroom, and how much they like to  get stuck in with activities - especially if it includes getting their faces covered in charcoal and giving me a charcoal beard!

My day in the woods with the Year 2 Class

The day in the forest with the Year 2 class was such a great experience! It gave me opportunity to really look at the benefits of forest schooling and how different it is to your usual classroom.

The day gave me opportunity to show pupil’s how to make cupcakes in orange skins, and begin to talk about irreversible change. The original plan was to make eggs in the skin but then soon figured we needed something which would really interest the children! We were aiming to touch upon key ideas of irreversible change and how it works; we had to take into consideration the children’s age and therefore the pitching of the content of the teaching. The way we approached this was to ask children their thoughts on cooking, and compared how baking a cake means that you wouldn’t be able to get the mixture back. However melting ice is a reversible change and tried to take this approach to give them something to apply the ideas to. We asked the children to have a very hand on approach to the activity ensuring that they were always engaged. They scooped the insides out of the oranges and made the cake mixture, pouring it into the orange skins. Then Richard put the oranges onto the fire to bake, at the end of their day children were allowed to take one if they so wished.

On the other hand although the activity was successful it did have its faults, ideally we would have more time and space to conduct the activity in. We could have also perhaps pre scooped out the oranges as this was not key to the learning objective of the activity and was quite time consuming, messy and difficult for some of the pupils. Maybe a practise run ourselves may have told us this but time was not permitting, however I do feel the activity was overall a success as the pupils enjoyed themselves!

Jess Tracey.

Making Popcorn with Red Class (Zoe)

My day in the woods with the year two class was enjoyable but also an interesting opportunity to talk to and observe children as they explored the outdoors.

The task I led was making popcorn on the fire at lunchtime - an optional come-and-go activity. The practicalities of the task were tying together two sieves containing popcorn kernels in, tying the sieves to a long stick, and put over the fire (avoiding setting the string alight) until popcorn is made.

I had a practise run by myself whilst the children were constructing their dens and discovered that the stick I was using was not long enough and it would be a safety hazard to have children sitting that close to the fire. With a bit of help I found a longer one which was heavier but safer.

When the children came to make popcorn the longer stick turned out to be better anyway; two or three children at once could hold it and be at a safe distance. I talked to the children about whether they’d seen popcorn being made before and I discovered that about half of the children that participated had seen at home popcorn made from the kernels before, and half hadn’t. I talked to the children about what they thought was happening to make the corn turn into popcorn and with two boys in particular we talked about the water inside the kernel and how it heats up/ gets excited etc. The girls were less interested in talking about the science of what was happening and seemed happier to sit back and watch me make the popcorn. The boys however tended to want to talk and be involved and close to the fire.  

A criticism of the activity is that the popcorn took a long time to get going – a few children lost interest because they were just waiting for it to heat up. The other thing was it was quite a lot for me to do on my own and I had to stop early because my eyes were stinging from the smoke! However another time this would not be a problem because Emma and I would take it in turns. All in all, I think it was a successful lunchtime making popcorn!

Which should we choose for woodlands like Seeley Corpse- to be ‘wild’ or to be managed actively so they stay ‘natural’?

Which should we choose for woodlands like Seeley Copse- to be ‘wild’ or to be managed actively so they stay ‘natural’?

MANAGED

Arguably woodlands can be seen as one of the UK’s most iconic and rewarding habitats. Woodlands provide a range of services from recreational, to sustainable natural resources. Many of the systems which use these goods sustainably have since collapsed. This has had damaging effects, for example, Hazel poles are much better for garden use and desperately need removing from neglected coppice but it is cheaper to buy bamboo poles imported from Asia.

Many of our local woodlands are no longer managed because they have stopped providing any economic benefit. Although recently the value of the woodland has been recognised, and the loss of land has decreased, the biodiversity this habitat contains is still under threat. The woodland management decline that has occurred has placed, not only rare, but many widespread species in danger. The concern is that only a small area of woodland will be left remaining to support a handful of the most common plants.

The key reason for these concerns is down to the decrease in woodland management. Many woodland areas have been fenced off and are becoming overgrown or simply overgrazed. In times where the woodland was part of the working community the people using the forest would visit different areas thus creating a patchwork of habitats. This caused biodiversity to blossom as the woodland responded to this long term cyclical management. With the decline in this management many types of woodland have sunk into neglect, and the mosaics of habitats have been lost to dense scrub and darkness, where few species are found.

WILD

Clearly woodland management techniques are vital for preserving the UK’s biodiversity. Nevertheless sometimes woodland management isn’t always the most appropriate course of action. A key example of this is illustrated when considering climate change. This can cause two problems, one being the need for differentiation when it comes to planting and management techniques. The other is in ensuring that management of the woodland now is appropriate to both current and future climate change implications.

Currently woodland management can involve the planting of local stock which is taken from seeds that come from native trees in the area, this management method is important for maintenance of the local biodiversity. However this approach is flawed when considering climate change. It assumes that, although the tress will be adapted to the current climate, they will also be adapted to the future climates, a prediction that is not an accurate one.  This provides a strong argument to review the use of woodland management in this way.

In conclusion the best option appears to be careful management of Seeley Copse to ensure that the wide variety of biodiversity that the woodland holds is preserved. Seeley copse in the last century has had a variety of what are considered ‘exotic’ tree species planted however due to a lack of management in 2009 these trees were felled to allow the woodland more light. Therefore if management is to occur in the woods then this needs to be maintained and a variety of different tree species need to be planted to provide the widest chance of adaptation for future climate changes.

Lauren Harden 

http://www.ferntreeservices.co.uk/index.php?content=4

http://www.goodwood.co.uk/goodwood-estate/educational-visits/seeley-copse-nature-trail.aspx

http://www.plantlife.org.uk/wild_plants/key_habitats/woodland/

http://www.woodlands.co.uk/blog/flora-and-fauna/climate-change-and-woodland-management/

Emma and Zoe's Forest Hut Photo

Our amazing forest hut, where creatures of the forest could live...

Types of Precipitation

If anyone wants to find out more about precipitation, here is a fun, easy to understand, youtube video to watch:

http://www.youtube.com/watch?v=vNIPBfKbec8


Emma, April 7th 

What is hail?

What is hail?

Hail is precipitation in solid form. It can vary in size from smaller than peas to larger than golfballs!

Ice is formed when condensation in the sky freezes solid, and this turns to hail when it starts falling but gets pushed back upwards by warmer air. This cycle continues multiple times, each time adding a layer of ice to the hailstone, until it falls to the ground. “If you cut a hailstone in half, you would see alternating concentric layers inside it.” (http://weather.about.com/od/h/g/hail.htm)

Holding the very large hailstone that fell in her garden:

Sources used:

http://www.crh.noaa.gov/fsd/?n=hail2007aug21_dante

http://weather.about.com/od/h/g/hail.htm

(Zoe)

Year 2 woods visit

Year two woods visit 19^th March 2012

Monday in the woods showed me how important forest schools are to children’s learning and just how effective they can be. The children had a great time and were eager to become involved in the new and exciting activities around them. Without realising it the children were building upon what they had learnt in the classroom and then taking this further by becoming actively involved in their own learning.

At the start of the day Harriet and I lead the first activity. This involved the children translating a series of messages that had been carved into logs from runes into English. They were given a translation sheet and asked to decode the directions from the clearing, up the pathway to the fire circle. In order to allow full participation and inclusion we split the children into groups and then staggered the sending of each group. This worked well and the task was very successful.      

However the task unfortunately didn’t involve a large amount of science, although it did use the children’s English skills with the ability to find the right letters, write them down, then spell and read the word. It also involved the children identifying different symbols and then finding the corresponding letter.

It didn’t take the children long to take up the task and get the hang of what they needed to do. This was good as almost straight away they became engaged and eager to find the next clue. I altered the activity whilst carrying it out by swapping the child who wrote down each translation as I soon realised some children were more dominant than others. I also chose children every so often to translate a letter who were very capable but shy, and as a result tended to remain quiet. By doing this all children could feel included and reach a sense of accomplishment.

I was surprised by the children’s teamwork with some offering to hold the log so that everyone could see it during the translation. I was also impressed when one child recognised the word ‘the’ in each clue because he remembered the signs from before and this gave him a sense of achievement each time resulting in further engagement.    

The only slightly difficult part for the children was when two symbols looked similar and then choose the wrong letter. Sometime this was due to the symbols we used, or the way the letters had been carved. However after saying to the children ‘I don’t think that’s quite right, have another look’ they soon came to the right answer and happily carried on, with some remembering which letters looked similar for next time the problem arose.

Overall the activity was successful and the children were all able to become involved and feel included. I believe the activity was pitched and delivered at the right level and this is backed up by the children’s overall success. I would feel confident in carrying out the activity again as the children seemed to enjoy it and it provided a great start to the rest of the day. 

Lauren Harden 

Thoughts on Grouping

Having just read Duncan's email saying that there are 20 boys and 9 girls in Red class, I think it would be sensible to pair up the girls so they're not left on their own and outnumbered by boys within a group. What does everyone else think?
(Zoe)

Insect Hibernation

Do Insects Hibernate in Winter?

Many insects hibernate as adults; they each have their own method for surviving the conditions of the winter season. Lady birds for example, congregate in large numbers in the fall at high levels above ground. Tree holes, leaf litter, and under logs and rocks are all places insects hibernate in winter. In some insect larvae, the water content of its body is reduced and it builds up glycerol which acts as an antifreeze. Generally, it is easier for insects to survive cold temperatures when the temperatures are stable rather than fluctuating.

A ‘sleep time’ which is different to hibernation is known as diapause. This is usually done by insects and is a delay in the insect’s development where they do not grow. There are two types of diapause. One type is called obligatory. This is where the insect must go through diapause at some stage in its development. The second type is called facultative. This is where the insect ‘sleeps’ because of adverse weather conditions. However, unlike hibernation, the insect ‘sleeps’ before the adverse weather.

Before the insects leave diapause and begin developing again, they receive warning signs, such as; the days get longer (which the insects can sense) and/or the outside temperature increases. In conclusion, diapause is simply the way ‘animals adapt to the world around them’.

References: (All Accessed 27^th February 2012)

www.si.edu/Encyclopedia_SI/nmnh/buginfo/winter.htm

http://www.riverwestcurrents.org/2004/February/001376.html

http://library.thinkquest.org/TQ0312800/diapause.htm

By Emma Barkley, 27^th February 2012

Can you suffocate in snow?

Can you suffocate in an avalanche?

It is true that you only suffocate in snow, you cannot drown as drowning is where your lungs fill with water, and snow would have to melt to be water no longer making it “snow”.

     

Suffocation in snow is a condition, known as Snow Immersion Asphyxiation (SIA) or Non-Avalanche Related Snow Immersion Death. Most snow related suffocations occur due to skiers falling in tree wells headfirst. (see below for diagram of tree well.) Deep snow accidents occur when a rider falls into an area of deep unconsolidated snow and they become immobilized. If the individual struggles in the snow they will either sink further or become more trapped as the snow solidifies like concrete around them. It is advised that “If you get sucked into a tree well or fall in deep snow attempt  to tuck, roll, and land upright, grab the tree trunk or a branch, and yell to alert your partner. If buried upside down, stay calm and create an air pocket, which could buy you some precious minutes of oxygen”.

See to the left the individual is 6ft tall however you can only just see their head out of the tree well.

The key to surviving SIA is by travelling with a buddy and carrying an avalanche beacon. If an individual does not travel with a buddy the chances of survival after entrapment become very slim. In some cases people can die due to snow suffocation as quickly as they can drown in water (usually as fast as 15 minutes). Most cases of SIA are recorded in December and January due to the weather conditions in this season. Many people concern themselves that they may become get hypothermia when trapped, however your body will not survive long enough to get this when submerged.

Asphyxia is a term referring to breathing insufficiency leading to inadequate intake of oxygen and inadequate exhalation of carbon dioxide. The suffocation begins as snow blocks your respiration, thus your heart will accelerate, trying to feed oxygen to your body. When your heart beat reaches 220 beats per minutes, the heart will stop working as a pump, therefore no blood can be carried. You will feel as if you're fainting as your brain gets no oxygen. Unless immediately defibrillated, your heart then stops working all together.

The odds of surviving a deep snow immersion accident are low; especially if you are not with a partner. In two experiments conducted in the U.S. and Canada in which volunteers were temporarily placed in a tree well, 90% could not rescue themselves.

% of Tree Wells & Deep Snow  involved in SIA cases

Posted by: Jess 

28.2.2012

Sources: 

http://howto.wired.com/wiki/Survive_Deep_Snow_Immersion

www.treewelldeepsnowsafety.com/tree_wells.php

www.treewelldeepsnowsafety.com/

www.safete.com/safetyarticles/parents/suffocation.htm

http://www.adventuremedicalkits.com/blog/2011/01/avoiding-snow-suffocation-hazards-at-the-ski-resort-and-in-the-backcountry/

http://sids-network.org/experts/carroll2.htm 

What are glaciers and how are they formed?

Glaciers are made up of layers of fallen snow that over many years has been compressed. This compression causes the snow to re-crystallises into granules similar to that of sugar. Over time the continued compression of the snow reducing the air pockets between them as the crystals become larger to form large ice masses. They currently occupy 10% of the earth’s land mass and are mainly found in Greenland and Antarctica.

These are a particularly interesting aspect of snow and ice as they have the ability to move. When ice is put under this large strain the ice will fracture. Water is a substance that under pressure lowers the temperature the solid to liquid transition takes place at, in this case sub-zero. This causes a lubricating film of water to form under the glacier, which along with gravity and the weight of the ice causes it to flow downhill. Movement along the underside of the glacier is slower than the top due to the friction made by the grounds surface.

Here is an experiment that could be used to demonstrate the flow of a glacier.

Flubber Experiment

Materials

·         Warm Water

·         White Glue(Elmers)

·         Borax

·         PVC pipe cut in half

·         Clingfilm

·         Cooking Oil

·         Sandpaper

·         Ruler

·         Freezer/ Microwave

Firstly create two mixtures the first consisting of a ¾ cup of warm water and 1 cup of glue. The second is made up of 2tbs of borax and ½ a cup of warm water. Next combine the two together and work through the hands until a consistent texture is reached.

 The children can then experiment with what can influence the speed / flow speed of the glacier. They could change the independent variable to; steepness of the slope, temperature of the flubber or even the conditions at the base of the flubber in order to experiment what the effects could be.

Glaciers often have rocks and debris underneath them which can restrict flow this could be demonstrated with the use of sandpaper which will significantly increase friction. Similarly some glaciers have a thin film of water underneath them. This can be modelled by smearing cooking oil over the PVC tube. By experimenting with all this different ideas the children can begin to grasp the idea of just how glaciers move in a fun and hands on way.

How far south did glaciers come?

Whilst glaciers in England only reached as far south as Oxfordshire around the world glaciers came so far south that they actually appeared in the tropics. The tropics are defined as 30ºN and 30ºS latitude. Some examples of glaciers in this area are Yanapaccha glacier, Peru and the Elena glacier near the Republic of Congo and Uganda border. However, as you can see from the pictures below they are rapidly depleting.

Elena Glacier 1906-1994

Could the South Downs have been affected by glaciation?

125 million years ago the south east was covered with fresh water lakes and rivers which carried clay building up layers at the base of the river. Soon after the sea began to break through laying down chalk made up of skeletons of dead sea creatures this created the bases of the South Downs.

The South Downs were originally formed by two tectonic plates (Eurasian and African plate) colliding the pressure at the point of impact caused the area to be upwards creating mountain chains. This is called alpine orogeny.

 Whilst no glaciers reached the South East the tundra like conditions which can be found on the edge of ice sheets dominated this area. As Carter states “Frozen chalk prevented further absorption.”(1990) this meant that the summer rain and melt water formed streams which carved out valleys. As the climate rose the water began to soak through the chalk which is an example of an aquifer which is a type of rock with small holes like pores which allow water to soak through leaving what is called dry valleys.

So in answer to the question posed whilst glaciers did not cause the formation of the South Downs . The freezing cold temperatures caused by the Ice age did however, aid the erosion process which shaped the already existing South Downs.

Resources I Used.

·         http://www.weatherquestions.com/What_causes_glaciers.htm

·         http://nsidc.org/cryosphere/glaciers/questions/what.html

·         http://www.realclimate.org/index.php/archives/2005/05/tropical-glacier-retreat/

·         http://www.southdowns.gov.uk/learning/themes-to-study/landscape/geology/geology-through-time

·         http://www.naturalengland.org.uk/ourwork/conservation/geodiversity/englands/counties/area_ID34.aspx

·         Timothy Carter (1990) Encyclopaedia of Brighton

What are lichens and how do they live?

Lichens are fungus and algae in a symbiotic relationship. The fungus is the visible part of the lichen, and it acts as a protector for the algae, enabling it to survive in harsh conditions that it would not be able to survive in alone. The algae contains chlorophyll, which enables it to photosynthesise, providing nutrients for the fungus. The same fungus can combine with different algae, and similarly the same algae can combine with different fungi, to make variations of lichens.

Lichens can live and grow almost anywhere, from rocks to trees to desert sand, and as they are often the first to inhabit hostile conditions, they provide the foundations for a lot of environments. To enable them to survive extremely difficult conditions, lichens are able to shut down metabolically but still survive until the conditions turn favourable again. Most lichens grow very slowly - only about a millimetre per year.

The explanation of why lichens would be found on one side of the log but not the other, is most likely because the side the lichens were not growing on was the side touching the ground, and the exposed side is a better environment for the lichens, with more space, air and sunlight.

Sources:

http://www.hiddenforest.co.nz/lichens/what.htm

http://www.countrysideinfo.co.uk/fungi/lichens.htm


(Zoe)

How does hibernation work? By Lauren Harden

How does hibernation work? What do insects do?

In autumn hibernating animals eat extra food while it is plentiful. This is stored as body fat in order to be used later for energy. Hibernators have two kinds of fat: regular white fat and a special brown fat. The brown fat forms patches near the animal's brain, heart and lungs. It sends a quick burst of energy to warm these organs first when it is time to wake up.
During hibernation the animal’s body temperature drops and their breathing and heart beat slow down significantly this reduces the energy consumption. For example, a hibernating woodchuck's heart rate slows from 80 to 4 beats per minute, and its temperature drops from 98 F to as low as 38 F. However if their body temperature drops too low the animal will wake up and shiver to raise their temperature.

How do animals know it is time to hibernate?

This is still being widely researched. It is believed that hibernating animals have something in their blood called HIT (Hibernation Inducement Trigger). Recent research suggests that it is some kind of opiate, chemically related to morphine. HIT is triggered as the days become shorter, the temperature changes, food becomes scarce and as a result hibernation occurs. How and why it happens are still a mystery.

Insects

Insects all behave slightly differently during winter, each adopting separate approaches to staying warm including:

Communal living

This is when insects find warmth in numbers. Honey bees group together for warmth and ants head deep underground with large food supplies where the stay sharing body heat throughout winter.

Torpor

This is a temporary state of sleep which keeps the insect still and unmoving in order to conserve heat and energy. Some insects do this at night and during the day come out of torpor to continue as normal.

Diapause

This is a long term state of suspension. This allows the insects life style to be in sync with the seasonal climate. If the conditions are too cold to find food or migrate the insect will pause during development.

Eggs of the praying mantis only emerge during the spring.

Larvae of caterpillars curl up in leaves and only spin their cocoons in the spring.

Pupa Black swallowtails spend winter as chrysalids, emerging as butterflies when warm weather returns.

Adult Mourning cloak butterflies hibernate as adults for the winter, tucking themselves behind loose bark or in tree cavities.

Antifreeze

Many insects are prepared for the cold weather because they produce their own antifreeze. During the autumn insects produce glycerol which gives the insect the ability to allow body fluids to drop below freezing points without causing ice damage. Glycerol also lowers the freezing point, making insects more cold-tolerant, and protects tissues and cells from damage during icy conditions in the environment. In spring, glycerol levels drop again.

http://www.sciencemadesimple.com/animals.html
http://insects.about.com/od/adaptations/p/wintersurvival.htm