Unit 7 Reflection

   This unit was all about Ecology, and the different aspects and how they all affect the Earth. We talked about the difference between habitats, all aspects of where an organism lives, and niches, all factors that the species needs to survive. Biotic factors are living things, and abiotic factors are nonliving things. An important theme in ecology was homeostasis and interdependence. Homeostasis refers to the idea that environments are healthiest when in balance. Interdependence is a concept that all living things in an ecosystem rely on each other as well as abiotic factors for survival. Another key idea is that all energy originally comes from the sun, then to producers, and then to consumers. 

Diagram showing global productivity in different regions. 

   Producers(autotrophs) provide energy for other organisms in an ecosystem. Consumers(heterotrophs) are organisms that consume energy by eating other living, or once-living things. There are herbivores, omnivores, carnivores, and detritivores. Trophic levels are levels in a food chain that are based on what something eats. Food chains and food webs model the flow of energy in an ecosystem in different ways. 
   Energy pyramids show how energy is transferred up the food chain. Food web dynamics explain the domino effects that occurs when populations at the top and bottom of the food chain decline. Another important concept is the levels of organization: organism, population, community, ecosystem, biome, biosphere.
   The 10% rule states that of energy produced/consumed at each trophic level, only 10% of that energy is transfered up the food chain. This is because the other 90% is lost through heat and waste. In population ecology, terms like density and dispersion are used. Density refers to the number of individuals in a given area, and dispersion refers to the pattern of spacing among those individuals in that area. Some factors that can affect population size are immigration, emigration, births, deaths, disease, predators, limited resources and competition.
   Exponential growth in population is most common in bacteria and viruses and well as species rebounding from near extinction. Exponential growth cannot be sustained in any population because they reach limits known as the carrying capacity(K). Carrying capacity is the maximum population size and environment can support. In the logistic growth model, the rate of population increase slows down as carrying capacity is reached, it does not level off. 
   Another topic discussed was ecological succession, which is the sequence of changes in an ecosystem in response to a disturbance. Primary succession is when succession begins without soil to start. Secondary succession begins in an area where soil remains after the disturbance. The stages of succession are as follows: Pioneer species(grasses, lichen, moss), intermediate species(shrubs and tress), and climax community(trees at full maturity). 

Diagram showing the different stages of succession and examples of the types of plant species commonly involved. 

   The nutrient cycles include the water, carbon, phosphorous, and nitrogen cycles. Water is essential to all life. Carbon is the building blocks for all life. Nitrogen is essential to life in the form of DNA and proteins. Phosphorous is critical to life in DNA, ATP, and lipids. 

   Another topic discussed was biodiversity, which is the total number of species in an ecosystem. Genetic diversity is related to all the different genes within a population and between populations. Species diversity is the variety of species in an ecosystem or biosphere. Ecosystem diversity is the different types of ecosystems throughout the planet. An endangered species is in danger of becoming extinct, while a threatened species is at risk for being endangered. Mass extinctions are widespread, rapid, decreases in biodiversity. Only 5 in history have occurred, but we are currently in the middle of the 6th. This is related to the rapid pace of human population growth. Background extinctions are extinctions that happen normally. 

   The main causes of species loss can be traced to 4 major threats. The first, habitat loss, is caused by human farming and development. The second, exotic species, are caused by humans relocating species from their native location. The third is overexploitation, caused by human harvesting of wild plants or animals. The fourth is change in climate, because species are adapted to a specific range of abiotic factors by nature, and drastic changes outside of their niches causes species to die(especially plants i.e drought or excessive rainfall).

   Plants are the producers, or foundation for the entire ecosystem. From the sun's energy, they provide to the rest of the consumers in the ecosystem. Without them, there's nothing. I wonder how in the future, some super industrialized cities will have enough oxygen for humans to breath considering the few trees. Already, with fossil fuel pollution it is hard to breath in big cities, but will it get worse? How can this be prevented so we can take a step back from the industrialization and restore parts of our natural ecosystem?

   For our conservation biologist project, we easily came up our topic: the arctic tundra. We began our team contract and assigned roles for research with ease. But when it came time to condense our research and begin writing the slides, I ended up doing the entire thing. Luckily, we were able to finish our recordings in class, where Kai then volunteered to do the editing. Overall, it was a rocky experience, because it was difficult to contact people when I needed to, but I think it has made me more assertive. Overall, I think I had been more passive and patient with the group to an extent that was creating conflict for the terms of the project getting done. The experience has given me more of an active voice to listen to others, but make clear what I would like.
   We also watched the story of stuff videos and I posted on my blog a summary and reflection of another video, as well as notes and a response to a question about "The Story of Stuff." You can view it here: Story of Stuff and Story of Cosmetics

Works Cited

Carbon Cycle. Digital image. National Center for Atmospheric Research. N.p., n.d. Web. 8 Mar. 2017. <https://eo.ucar.edu/kids/green/images/carboncycle_sm.jpg>.

Global productivity and sunlight angles on earth. Digital image. Quia. N.p., n.d. Web. 8 Mar. 2017. <https://www.quia.com/files/quia/users/lmcgee/ecology/sun_angle_latitude.gif>.

Nitrogen Cycle. Digital image. Partnerships for Environmental Education and Rural Health. N.p., n.d. Web. 8 Mar. 2017. <http://peer.tamu.edu/curriculum_modules/Environ_Hazard/images/nitrogencyclesmall.jpg>.

Phosphorous Cycle. Digital image. Wordpress. N.p., n.d. Web. 8 Mar. 2017. <https://raceingminds.files.wordpress.com/2013/06/phosphorous-cycle.jpg>.

Stages of Succession. Digital image. Slide Share. N.p., n.d. Web. 8 Mar. 2017. <http://image.slidesharecdn.com/succession2009-110426161751-phpapp01/95/succession-2009-19-728.jpg?cb=1303834862>.

Water Cycle. Digital image. NASA Precipitation Measurement Missions. N.p., n.d. Web. 8 Mar. 2017. <https://pmm.nasa.gov/education/sites/default/files/article_images/Water-Cycle-Art2A.png>.