Japan

 

Part 1: Soils and the Physical Environment

Japan is an incredibly ecologically diverse nation. Thus, I wanted to choose three regions that really highlight the variation of soils, climate, and landforms in the region. My three regions are the Akan-Mashu National Park, the Yakushima National Park, as well as Mikawa Bay and the surrounding area. Below is a map illustrating my three research regions, each labelled with a purple symbol. 

Due to some issues with translation, it has been difficult to discern the exact composition of the soils in my selected regions. I will give the soil classification as it is listed on the Japanese NARO (National Agriculture Research Organization) website, as well as describe the content of the soil.

The soil compromising the majority of the Akan-Mashu National Park is listed as "ordinary volcanic emission soil" and is given a classification of J1z1. This soil is characterized as having a high level of volcanic ash and other debris from volcanic eruptions with very little amounts of clay. The NARO website states that this soil is used in agricultural fields and gardens, meaning that it is highly fertile and has the capacity to hold a good amount of water. 

Image credit: 日本土壌インベントリー (affrc.go.jp)

The soil compromising the Yakushima national park is listed as "Humus Brown Forest Soil" with a classification of I1h3. The NARO website characterizes brown forest soil as soil with brown or tawny "fusing layers," most often located on mountains and hills with little influence from volcanic ash. This type of soil specifically has a layer of humus on top of it. Humus is dark organic material that forms when plant and animal matter decays. 

Image credit: 日本土壌インベントリー (affrc.go.jp)

The area surrounding Mikawa Bay has highly diverse soil composition. While using the interactive map of the NARO website I counted five different soils (each one separated into small-puzzle piece like regions). Thus, I chose one soil I found to be unique. This soil is labelled "Red-Yellow Soil with Red Clay Accumulation," and is given a classification of G1k1. The NARO website describes this soil as red-yellow soil with a layer of red clay accumulation. This soil is generally in advanced stages of weathering, and has very little organic matter. 

Image credit: 日本土壌インベントリー (affrc.go.jp)

As mentioned previously, the diversity of landforms in these three regions is astounding. For example, the crater lake of Akan (located in the Akan-Mashu National Park) is home to a rare form of algae known as marimo. This algae forms into vibrant green spheres, known as marimo balls, which can reach the size of a soccer ball (Soejima, et al. 2008)! The Yakushima National Park, on the other hand, is filled with trees that reach up to 1,000 years old (UNESCO). This national park also houses the beautiful Okawa Falls, as well as Mount Miyanoura. Mikawa Bay is surrounded by the Chita Peninsula to the west and the Atsumi Peninsula to the east and south. It is home to sandy beaches and lush forests, as seen in the Horai-Kyo Valley. This variety also extends to the climates of Japan. Northern Japan, where Akan-Mashu National Park is located, tends to have warm summers with harsh winters. In contrast, Western Japan has hot and humid summers with moderately cold winters (Schaefer, Domroes 2009).

This is a climograph for the Akan-Mashu National Park, located in the Hokkaido prefecture.

This is a climograph for the Yakushima National Park, located on Kuchinoerabu-jima island, which is located in the Kagoshima prefecture.

For the third climograph I chose to use the city of Gamagori, which is located directly on Mikawa Bay.

Part 2: Flora, Fauna, and Disturbance Patterns

To begin my discussion of the flora and fauna of these three regions, I will introduce the two species I chose from the Akan-Mashu National Park region: the Yezo Deer and Marimo algae. Both of these species are highly adaptive, and have evolved to thrive in their homes. For example, Yezo Deer are excellent swimmers. They can swim for long distances in order to avoid predators, and also have sharp antlers and hooves to aid in their defense (AnimalSpot 2019). Marimo algae is unique in that it can grow three ways: on rocks, free floating, and, as we see below, as balls of densely packed algae. They utilize columns of air in Lake Akan to ensure adequate photosynthesis and to retain their round shape (Boedeker, et al. 2010).

There are also limitations to the growth of these species outside of the range indicated below. For the Yezo Deer, this limit is anthropogenic in nature. Yezo Deer have the tendency to mate with Red Deer when females of their own species are not available, thus polluting the Red Deer population. Thus, there has been a great deal of regulation on the irruptions of populations of Yezo Deer (Uno et al. 2008). For the Marimo algae balls, their unique nature can also be their downfall. Because they rely on air columns (and other outside forces) to turn them regularly, they cannot survive in places that lack these factors. Their growth cycle does not have a so-called "dry period" either, thus they cannot survive being moved from one place to another by birds and other wildlife (Soejima et al. 2009, Boedeker, et al. 2010).

This image is showing some of the larger variations of Marimo algae balls.

Image Credit: Moss Balls of Lake Myvatn and Lake Akan | Amusing Planet

This photo is of a young male Yezo Deer.

Image Credit: Yezo sika deer - Wikipedia

Below is a photo indicating the ranges of both species.

Base map link: Akan Mashu National Park Travel: Lake Kussharo (Kussharoko) (japan-guide.com)

The two species I chose for the Yakushima National Park region are the Yakushima Macaque and the Loggerhead Turtle. The Loggerhead Turtle has many adaptations that allows them to survive on Nagata Beach of Yakushima island. First, they possess the ability to swim great distances. They are able to find different food sources if the local one becomes depleted. They also have extremely powerful jaws, which allows them to crack the shells of other crustaceans. The Yakushima Macaque has adapted so that their behavior changes depending on the weather (Hanya et al. 2018), and they also know how to forage for hard to reach foods. Interestingly, they have also been observed washing food to remove dirt and other imperfections from their morsels (Nakimichi et al. 1998)! 

As with the other species mentioned here, the Loggerhead Turtle and Yakushima Macaque have some limitations when it comes to their ability to expand their habitats. One of the largest issues for Loggerhead Turtles is their reproductive cycle. They must travel long distances to find nesting beaches, and only make this voyage once every two to three years. They also lay their eggs on sandy beaches, which means that many of the hatchlings do not survive (National Wildlife Federation). The Yakushima Macaque is unique in that it is technically a subspecies of the broader Japanese Macaque species. This means that they are adapted to the unique circumstances and environment of Yakushima island, which makes them ill-equipped for living in other regions (Hanya et al, 2020).

Below are two images of the species described above. The first is the Loggerhead Turtle and the second is the Yakushima Macaque. The third image is a map of the range for both species.

Image credit: Loggerhead Sea Turtle | National Wildlife Federation (nwf.org)

Image credit: Nature Picture Library Yakushima macaque (Macaca fuscata yakui) group, Yakushima Island, UNESCO World Heritage Site, Japan. Endemic to Yakushima Island. - Cyril Ruoso (naturepl.com)

Base map link: Yakushima, Kagoshima-ken, Japan - Google My Maps

The two species I chose for the Mikawa Bay region are the Japanese Eel and the Moon Jellyfish. The Japanese Eel is an interesting critter due to its ability to leave water and travel on dry land for short periods of time. This allows them to bypass aquatic predators and obstacles, as well as leave isolated bodies of water (Peaslee 2009). This is a great boon as their lifecycle is split between fresh water and marine periods (Toyokawa et al. 2011). They also become transparent during a specific point of their lifecycle, which protects them during a vital part of their life (Peaslee 2009). The Moon Jellyfish are unique in their adaptations as well. They have nearly transparent bodies, which allows them to hide from predators. They also have stinging nematocysts on their tentacles. The mild toxin released by their appendages can both deter predators and subdue prey. One unique adaptation is that they thrive in areas of high anthropogenic activity, where other species fail (Purcell et al. 2007).

These unique species also have some severe limitations when it comes to range growth. In the case of the Japanese Eel, their status as a edible delicacy has nearly decimated their populations (McCurry 2018). Moon Jellyfish, despite their ability to capitalize on anthropogenic activity, have a limited range due to their status as weak swimmers. They can become stranded on beaches and other obstacles easily, and cannot travel great distances (Toyokawa et al. 2011).

Below are images of the species described above. The first image is of the Japanese Eel, the second is the Moon Jellyfish, and the third is a range map I created to illustrate their habitats.

Image credit: ウナギ目 - Wikipedia

Image credit: Biologists Surprised by Unique Strategy of Self-Repair Discovered in Moon Jellyfish | Biology | Sci-News.com (sci-news.com)

Base map credit: Hukue (Aiti), Aichi, Japan Tide Station Location Guide (tide-forecast.com)

Japan has several prevalent patterns of disturbance. One of the most common of these is typhoons. Forests in regions such as the Yakushima and Akan-Mashu National Park suffer periodic mass tree blowdowns due to typhoons (Nakashizuka, Iida 1995). These large-scale tree upheavals not only destroy flora, but also leave many animals without homes. The typhoons themselves can drown and wash away many animals, especially those who live closer to the shore (Nakamura, Swanson, Wondzell 2000). Species such as the Moon Jellyfish, Loggerhead Turtle, and Japanese Eel are especially vulnerable because of their aquatic nature. 

Another disturbance pattern that affects all of Japan is their frequent earthquakes. Earthquakes can cause everything from mudslides to complete ecological collapse, and everything in-between. Animals such as shorebirds and Loggerhead Turtles can be swept up and away in resulting tsunamis, totally disrupting the ecosystems of shorelines (Goldman 2011). The effects can also be felt by mainland species as well. Flood waters can cause significant disruptions to their environments and food chains, as well as cause significant upticks in mortality rates. 

Below is an image of the aftermath of Typhoon Hagibis in 2019.

Image credit: Typhoon Hagibis tears across Japan | News | DW | 13.10.2019

Aftermath of 2011 megaquake and ensuing tsunami.

Image credit: Timeline of Japan's 2011 quake, tsunami and nuclear disaster (apnews.com) 

Part 3: Stressors, Climate Change, and Conservation

While the Japanese government does an amazing job at protecting national parks such as Yakushima and Akan-Mashu, some anthropogenic stressors still exist in these environments. For Mikawa Bay primary stressor is overfishing and its consequences. Overfishing can seriously harm the ecosystem in many ways, including disrupting population patterns and pollution (Scheffer et al, 2005). As discussed previously, the Japanese eel is a staple in the nation's diet (McCurry 2018), and is readily available in Mikawa Bay. This makes them extremely vulnerable to overfishing and its consequences. For example, some pollutants can create neurotoxicity and immunotoxicity in eels (Drouineau et al. 2018).

The first image depicts a common dish made using eel and the second is an example of how many fish can be taken from an ecosystem at one time.

Image credit: Unagi - grilled freshwater eel (japan-guide.com)

Image credit: Building a Future for Japan’s Fisheries Industry | Nippon.com

As mentioned previously, the Japanese government is highly efficient in protecting areas such as Akan Mashu National Park and Yakushima National Park, however that does not mean they are immune from the effects of human-caused pollution. The main issue that Akan-Mashu faces is the disturbance of water regimes through a process known as eutrophication. This process causes overnutrition of the water, which directly leads to lower oxygen levels (Harper 1995). This process is devastating to most aquatic life, but especially so for the already endangered Marimo algae balls. Because Marimo take longer periods of time to grow and amass their characteristic sphere shape, thus they cannot thrive in oxygen-deprived water (Boedeker and Immers 2009).

Below is an example of a misshapen Marimo.

Image credit: The Natural and Forced Deaths of Marimo - MossBall.com

The main anthropogenic stressor that Yakushima National Park faces comes in the form of tourism. Yakushima National Park is a very popular tourist spot with over 200,000 visitors annually (UNEP-WCMC 2017). This many visitors can create a number of stressors for the environment, such as localized pollution, soil erosion, and even habitat loss. This can also impact the natural behaviors of animals if they are experience prolonged exposure to human activity. The loggerhead turtles are at great risk due to their tendency to ingest plastic litter that they mistake for prey animals such as jellyfish (Schuyler et al. 2014).

Below is an image of a group of tourists in the park.

Image credit: Yakushima seeks environment-tourism balance | The Japan Times

The high-emission model (RCP 8.5) predicts dire consequences for Japan and its wildlife. The mean annual temperature will increase by roughly 2 degrees Celsius (World Bank Group) and annual precipitation will increase by 87.42 millimeters (World Bank Group), and that is just for the years 2040-2059. It is projected that this will drastically impact the occurrence and intensity of typhoons in the region (Tsuboki et al. 2015). Not only will the occurrence of ordinary typhoons increase, but it is also hypothesized that the East Asian region will experience an increase in “super typhoons,” or typhoons whose winds reach speeds of over 150 miles per hour. (Tsuboki et al. 2015). This disturbance is closely related to another prevalent disturbance regime: flooding. The increase in rainfall and typhoon intensity will directly correlate with more frequent and intense floods. 

-        Species such as the Japanese eel are uniquely vulnerable to climate change. First, their lifecycle is split between freshwater and marine bodies of water (Peaslee 2009). This leaves them vulnerable to disturbance in both environments, such as pollution and rising water temperatures. For example, increased water surface temperature can increase the mortality rates for leptocephali, or marine eel larvae (Drouineau 2018). There is also evidence that suggests that changes in precipitation regimes can have severe impacts on the eel’s later stages of life as well (Drouineau 2018).

Marimo balls are extremely sensitive to disturbance (Boedeker et al. 2010) and thus would be the species most vulnerable to these climatic changes. They survive best in oligotrophic and mesotrophic lakes, and though Lake Akan is technically eutrophic, a serious decline in Marimo populations has been observed (Boedeker et al. 2010). This will only be exacerbated by increasingly polluted air and water, and the increase in rainfall will dramatically impact the characteristics of the lake.

-         While both species are vulnerable to climate change, it is the Loggerhead Turtle that seems to be in the most danger. Recent research suggests that marine turtles such as the Loggerhead are extremely vulnerable to sea level rise, as it dramatically decreases the availability of nesting beaches (Witt et al. 2010, Hawkes et al. 2007). Not only would these nests be in danger of flooding and general disturbance, but rising temperatures have also been shown to affect the success of turtle clutches (Ackerman 1997, Witt et al. 2010). For example, temperature affects the incubation success, incubation duration, and even the sex of the offspring (Witt et al. 2010).

As discussed previously, the government of Japan is extremely effective when it comes to the conservation of national parks and other federal wildlife reserves. However, there is always more that can be done to preserve such diverse ecosystems. Thus, I have drafted a handful of “points” or steps that can be taken to ensure the future of the three locations I have discussed thus far.

First, it would be beneficial to keep stringent watch over the Yezo Deer population in Akan-Mashu National Park. Yezo Deer are prolific maters and have been known to reproduce with another deer species, the Red Deer, thus polluting the gene pool of the other endangered species (Uno et al. 2008). Large herds also put the environment under a great amount of strain, as they quickly deplete their food resources, thus harming every other species in the region (Uno et al. 2008).

Second, more scrutiny should be placed on fisheries and individual trawlers to discourage overfishing. Overfishing causes sometimes irreparable damage to the environment and can obliterate entire species of marine fish species (Goñi 1998). Fishing boats can also contribute to pollution which, as discussed previously, can be disastrous for species such as the Japanese Eel (Drouineau 2018). This point leads directly to my next management action, which is this: the construction of sanctuaries or “safe zones” for endangered marine animals. Sanctuaries would allow the rehabilitation of these populations.

My final conservation action is specific to federally regulated areas such as national parks. The institutions governing these areas should implement a series of raised paths and observation decks to discourage human interaction with flora and fauna. Human-wildlife interaction can be disastrous, as it can disrupt breeding processes, damage habitats, and even evoke physiological changes (INTOSAI 2013). Thus, it is imperative that limits be placed on how close humans can get to these animals. Observation decks and raised paths would still allow a healthy flow of tourists through the park but would ensure that no contact is made between humans and animals.

When thinking about the relative vulnerability of my three locations I first considered the existing amount of regulation regarding their conservation. Thus, I would have to rank Mikawa Bay first. Both Yakushima and Akan-Mashu are national parks, meaning that they are much more closely guarded. Second, I considered the amount of human interaction with the environment itself. This led me to consider Akan-Mashu more vulnerable, as Yakushima is located on an island with a little over 13,000 inhabitants (Wogan 2018). Thus, my vulnerability ranking is as follows: Mikawa Bay as the most vulnerable, Akan-Mashu next, then Yakushima Island as the least vulnerable. 

Citations

Soejima, A., Yamazaki, N., Nishino, T. et al. 2009. Genetic variation and structure of the endangered freshwater benthic alga Marimo, Aegagropila linnaei (Ulvophyceae) in Japanese lakes. Aquat Ecol 43, 359–370. https://doi.org/10.1007/s10452-008-9204-9

Yakushima. UNESCO World Heritage Centre. https://whc.unesco.org/en/list/662/ (last accessed 6 April 2021).

Schaefer, D. and Domroes, M. 2009.  Recent climate change in Japan – spatial and temporal characteristics of trends of temperature, Clim. Past, 5, 13–19, https://doi.org/10.5194/cp-5-13-2009.

Boedeker, C., Eggert, A., Immers, A., and Smets, E. 2010. Global Decline of and Threats to Aegagropila linnaei, with Special Reference to the Lake Ball Habit. BioScience 60, 187-198.

 Purcell, J., Uye, S., Lo W. 2007.Anthropogenic causes of jellyfish blooms and their direct consequences for humans: a review. Marine Ecology Progress Series, 350, 153-174. https://doi.org/10.3354/meps07093

Toyokawa, M., Aoki, K., Yamada, S., Yasuda, A., Murata, Y., Kikuchi, T. 2011. Distribution of ephyrae and polyps of jellyfish Aurelia aurita (Linnaeus 1758) Sensu lato in Mikawa Bay, Japan. Journal of Oceanography 67, 209-218.

McCurry, J. 2018. Japan's appetite for eel could see it share fate of bluefin tuna. The Guardian. https://www.theguardian.com/world/2018/jul/06/japan-appetite-eel-same-fate-bluefin-tuna (last accessed 12 April 2021).

Peaslee, A. 2009. The Cycle of Life... http://bioweb.uwlax.edu/bio203/s2009/peaslee_alex/Anguilla_Japonica/Life_Cycle.html#:~:text=They%20can%20actually%20leave%20the,which%20allows%20them%20to%20slither.&text=A%20bucket%20of%20eels%20sitting%20in%20a%20Japanese%20restaurant. (last accessed 12 April 2021)

Hanya, G., Yoshihiro S., Hayaishi S., and Takahata, Y. 2020. Ranging patterns of Japanese macaques in the coniferous forest of Yakushima: Home range shift and travel rate. American Journal of Primatology 82 (10).

 Hanya, G., Y. Otani, S. Hongo, T. Honda, H. Okamura, and Y. Higo. 2018. Activity of wild Japanese macaques in Yakushima revealed by camera trapping: Patterns with respect to season, daily period and rainfall. PLOS ONE 13 (1).

Uno, H., K. Kaji, and K. Tamada. 2008. Sika Deer Population Irruptions and Their Management on Hokkaido Island, Japan. Sika Deer :405–419.

 Loggerhead sea turtle. (n.d.). Retrieved April 12, 2021, from https://www.nwf.org/Educational-Resources/Wildlife-Guide/Reptiles/Sea-Turtles/Loggerhead-Sea-Turtle

Nakamichi, M., Kato, E., Kojima, Y., and Itoigawa, N. 1998. Carrying and Washing of Grass Roots by Free-Ranging Japanese Macaques at Katsuyama. Folia Primatologica: International Journal of Primatology 69 (1).

Sika deer FACTS, Habitat, Diet, Pictures. (2019, April 03). Retrieved April 12, 2021, from https://www.animalspot.net/sika-deer.html#:~:text=Adaptations,often%20use%20for%20defense%20purposes.

Nakashizuka, T., Iida, S. 1995. Composition, Dynamics and Disturbance Regime of Temperate Deciduous Forests in Monsoon Asia. Vegetatio 121: 23-30.

Nakamura, F., Swanson, F., and Wondzell, S. 2000. Disturbance regimes of stream and riparian systems – a disturbance-cascade perspective. Hydrological Processes a4: 2849-2860

Goldman, J. (2011, March 22). Impact of the Japan earthquake and tsunami on animals and environment. Retrieved April 12, 2021, from https://blogs.scientificamerican.com/guest-blog/impact-of-the-japan-earthquake-and-tsunami-on-animals-and-environment/

UNEP-WCMC. 2017. YAKUSHIMA. World Heritage Datasheet. http://world-heritage-datasheets.unep-wcmc.org/datasheet/output/site/yakushima/.

 Schuyler, Q. A., Wilcox, C., Townsend, K., Hardesty, B., and Marshall, N. 2014. Mistaken identity? Visual similarities of marine debris to natural prey items of sea turtles. BMC Ecology, 14(1), 14. https://doi.org/10.1186/1472-6785-14-14

Boedeker, C., Immers I. 2009. No more lake balls (Aegagropila linnaei K-tzing, Cladophorophyceae, Chlorophyta) in the Netherlands? Aquatic Ecology 43: doi:10.1007/s10452-009-9231-1

World Bank Group. (n.d.). World Bank Climate Change Knowledge Portal. Japan. https://climateknowledgeportal.worldbank.org/country/japan/climate-data-projections.

 Tsuboki, K., Yoshioka, M. K., Shinoda, T., Kato, M., Kanada, S., and Kitoh, A. 2015. Future increase of supertyphoon intensity associated with climate change. Geophysical Research Letters, 42(2), 646–652. https://doi.org/10.1002/2014gl061793

Witt, M. J., Hawkes, L. A., Godfrey, M. H., Godley, B. J., and Broderick, A. C. 2010. Predicting the impacts of climate change on a globally distributed species: the case of the loggerhead turtle. Journal of Experimental Biology, 213(6), 901–911. https://doi.org/10.1242/jeb.038133

 Hawkes, L. A., Broderick, A. C., Godfrey, M. H., Godley, B. J. 2007. Investigating the potential impacts of climate change on a marine turtle population. Global Change Biology, 13(5), 923–932. https://doi.org/10.1111/j.1365-2486.2007.01320.x

Ackerman R. A. 1997. The nest environment and the embryonic development of sea turtles. In The Biology of Sea Turtles, vol. 1 (eds Lutz P. L., Musick J. A.), pp. 83-106. Boca Raton: CRC Press.

Drouineau, H., Durif, C., Castonguay, M., Mateo, M., Rochard, E., Verreault, G., Yokouchi, K., and  Lambert, P. 2018. Freshwater eels: A symbol of the effects of global change. Fish and Fisheries, 19(5), 903-930. 

Scheffer, M., Carpenter, S., and Young, B. 2005. Cascading effects of overfishing marine systems. Trends in Ecology & Evolution, 20(11), 579–581. https://doi.org/10.1016/j.tree.2005.08.018

Harper, D. 1995. Eutrophication of freshwaters: principles, problems and restoration. Chapman & Hall.

Goñi, R. 1998. Ecosystem effects of marine fisheries. Ocean & Coastal Management, 40(1), 37–64. https://doi.org/10.1016/s0964-5691(98)00037-4

INTOSAI Working Group on Environmental Auditing. 2013. Impact of Tourism on Wildlife Conservation. International Centre for Environment Audit and Sustainable Development. http://iced.cag.gov.in/wp-content/uploads/2014/02/2013_wgea_Wild-Life_view.pdf. 

Wogan, J. 2018. A Guide to the Otherworldly Island of Yakushima. The New York Times. https://www.nytimes.com/2018/05/17/t-magazine/travel/yakushima-japan-guide.html.