Woodland management

Woodland ecosystems are a key aspect of the countryside environment and are vital for the health of ecosystems through an array of ecosystem services through carbon sequestration, provide a range of many niches in a small area, prevent soil erosion etc. As deforestation appears to not be slowing down any time soon, it is important that  adequate management is undertaken in these declining habitats.

Coppicing is a common management technique which is clearing small sections of trees so more light may reach the ground flora. Following this practice, light increased by 4 fold in Spring and 20 fold during Summer time. There is a strong correlation between the amount of light reaching the floor and the diversity and abundance of the ground flora.

The level of shade, ride width and the cutting regime are all aspects that must be carefully considered when coppicing as it has a major impact on wildlife. The width of rides (path of cleared trees) must be 1.5 times wide as the height. To optimize the period of sunlight, these rides should run from east to west were the ground flora will be exposed to light for the sunlight period.

Cutting regimes are suggested to be cut on a 3 zone system which is more suited for nature reserves. The first zone will be cut once a year where 50% of grass species will be cut. The second zone will have 25% of vegetation cut and the 3rd zone will be left to allow natural regeneration to occur.



It is recommended that cuttings occur during Autumn time when invertebrates are less active while simultaneously promoting vigorous grass growth. Small cuttings in zone 2 during July won't have negative implications on invertebrates. Removal of grass growth is best to be performed during Spring time.

To further enhance the biodiversity in these woodland habitats, incorporating shaded, well lit streams are beneficial to most invertebrates and birds as a breeding site. Leaving the dead wood from the coppicing in semi shaded areas are valuable for fungi and lichen establishment. Arboreal species such as squirrels should also be accounted for where the canopy of the trees either side of the ride should be in contact with one another in order to allow these individuas to run from tree to tree.

Strong winds in these rides will disrupt the biodiversity especially the invertebrates. Long straight rides will encourage channeling of strong winds. To prevent this from occurring, curved rides are suggested.  
 
https://www.youtube.com/watch?v=FkRuMqVuJDE

https://www.youtube.com/watch?v=qg3Ucu6wYZw

Whale mucus reveals poor health during migration.

Researchers from the University of New South Wales (UNSW) had collected and obtained whale blow (equivalent to human mucus) from a sample population of Humpback whales. The target sample were derived from those returning to the west of Australia. This whale blow had been analyzed and noted that there was a reduced microbiota abundance and diversity compared to before their migratory voyage to the Antarctica.  

The lead author of this research, Dr Catherina Vendi, has a background in veterinary science and had stated the richness of a whale's airways is a strong indicator of the humpback whale's overall health. Prior to this research, Dr Vendi, had studied literature based on humans implicated with respiratory diseases with it being confirmed those experiencing these diseases showed a lack of microbial diversity within their airways.

The decline in the whale's health has been said to be due to prolonged period of fasting during their 8,000km migratory route from Queensland to the Antarctica. Over fishing is thought to be the primary contributing factor where the United Nations FAO's 2020 State of World Fisheries & Aquaculture report had revealed that global fisheries have been over fished with 34.2% of these fisheries poached beyond sustainable limits resulting in a 49% decline in fisheries between 1970 to 2012. 

These humpback whale populations rely on schools of fish such as cod, sardines, mackrel etc and so this reduction in fish populations will apply significant pressure onto the humpback whale population reducing fertility rates, immunity, adaption to environmental change etc.

This reduction has been a consequence of over fishing, pollution and climate change working in conjunction with one another. Pollution has also had an influential direct impact on the humpback whales which along with fasting is likely to reduce their immune system.

• Catharina Vendl, Eve Slavich, Bernd Wemheuer, Tiffanie Nelson, Belinda Ferrari, Torsten Thomas, Tracey Rogers. Respiratory microbiota of humpback whales may be reduced in diversity and richness the longer they fast. Scientific Reports, 2020; 10 (1) DOI: 10.1038/s41598-020-69602-x [Accessed 11 August 2020].
• Msc.org. 2020. Oceans At Risk | Marine Stewardship Council. [online] Available at: <https://www.msc.org/what-we-are-doing/oceans-at-risk?gclid=Cj0KCQjwg8n5BRCdARIsALxKb953AGrXGCLtPRD6ZBIweMxCEbPXr8sy0OVoMZykyp0z4V2-f_SXNwQaAl0IEALw_wcB> [Accessed 11 August 2020].

How climate change causes top heavy Aquatic food webs

 University of British Columbia (UBC), 25th / June/ 2020 - This research replicates the predicted rainfall patterns expected to occur as a result of climate change across 7 different sites ranging central and south America. The model ecosystem that had been used was winged larvae insects that lives under bromelaid plants. 

The results obtained from this survey revealed that large day to day variation in extreme rainfall patterns showed an increase in predator species and a decrease in the prey species and the insect larvae making the food web top heavy.  

The proffesor of zoology in UBC and co-author of this research, Diane Srivastava had discussed how negative this may be to the aquatic ecosystem but also emphasized how negative this will be to the forrest ecosystem as these model larvae are winged playing a massive role in the terrestrial ecosystem. 

The results that had been collected did not support the hypothesis set out initially prior to the survey. It was expected the predator species population would depleat as they are often more vulnerable to changes to the environment. 

This study can be applied to streams, rivers, lakes etc. This study should be performed for long periods of time where a cohort life table is formed. It is likely the prey species would eventually begin to rise because predator-prey interactions are commonly cyclical waves. As the prey species lowers, reproductive rates of the predator species will depress and mortality will slightly accelerate as this puts pressure on the predator species due to a lack of food source. I would hypothesize the long term effects of extreme rainfall patterns caused by climate change will cause high fluctuations in the aquatic populations. An unstable aquatic environment will be established which is likely to better support generalist species.

The longevity of these aquatic ecosystems subjected to these rainfall patterns is unknown and only educated guesses may be used to evaluate the long term effects at this point in time due to lack of research. As of now all that has been confirmed is that the rainfall creates a top heavy trophic cascade within the ecosystem.

Research

University of British Columbia. "Extreme rainfall events cause top-heavy aquatic food webs." ScienceDaily. ScienceDaily, 9 July 2020. <www.sciencedaily.com/releases/2020/07/200709085310.htm>.