Ecosystem Crises Interactions. Merrill Singer

Ecosystem Crises Interactions - Merrill Singer


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pulmonary fibrosis, a lung disease that occurs when tissue becomes damaged and scarred, making it difficult for the lungs to work properly and causing progressive shortness of breath. A new drug called AD‐114, which mimics shark antibodies, is being developing in Australia. It belongs to a class of therapies called i‐bodies, which are proteins that combine the features of small molecules and antibodies. In animal testing, AD‐114 has been found to only bind with scarred lung cells while ignoring healthy lung tissue (Pulmonary Fibrosis News 2016).

      At The Hague in 2002, the U.N. member states that signed on to the Convention on Biological Diversity agreed to a series of goals aimed at significantly reducing the rate of loss of animal and plant populations at the global, national, and regional levels—goals that have not been achieved. Blocking achievement are multiple threats to biodiversity (European Commission 2004), including:

       Unceasing expansion of industrial production, including many new chemicals,

       Promotion of hyper‐consumerism.

       Production of toxic waste and its release into the environment.

       Global increase in vehicular mobility.

       Stratospheric ozone depletion.

       Human population growth, leading to increasing demands for living space, food, and other resources. (The global human population has grown from approximately 1.65 billion in 1900 to an estimated 6.3 billion today, and is increasing by over 75 million a year. In 40 years, the United Nations predicts a world population of 9 billion).

       Urban expansion and commercial agriculture and forestry encroachments on habitats.

       Extension of roads, rail lines, airports, and electricity networks that fragment habitats and frighten away some species.

       Overexploitation of natural resources, including excessive hunting, collecting, and trade in species and parts of species.

       Pollution and its adverse effects on the health of animals and plants.

       Environmental disasters, such as oil spills that devastate marine and coastal fauna and flora.

       Climate change, which impacts ecosystems on the land and in the seas, causes sea level rise, enhances the intensity and frequency of wild fires, contributes to species decline and extinction, and significantly impacts health.

       Invasion of alien species, often introduced intentionally or unintentionally by humans, that thrive and overwhelm endemic species.

       Overfishing, which is depleting global fish stocks in lakes and oceans.

      a large percentage of terrestrial and aquatic species are facing elevated risk of extinction with climate change acting as a major driving force that is worsened by interactions with other stressors including habitat fragmentation and modification, over‐exploitation and harvesting, eutrophication, invading species, infectious disease, and chemical pollution.

      Another expression of ecocrises interaction is seen in the case of honeybees, which play a critical role in human food production. Research indicates that fruit, vegetable, and seed/nut production for 87 of the leading global food crops is dependent upon animal pollinators like bees (Klein et al. 2007). Historically, beehives in North America endured a die‐off rate of about 15 percent in the period between October and April because of the cold temperatures and lack of winter forage. Rates of loss, however, have almost doubled to 28 percent since the early 2000s as a result of the combined and interacting effects of stress, pests, diseases, and pesticide exposure (Goodrich 2017). In fact, in 2014, the United Nations reported that 40 percent of the plant pollinator species that are key to the world’s food supply are facing extinction. A member of the team that produced this assessment, Berry Brosi, assistant professor of environmental sciences and bee researcher at Emory University in Atlanta, stated: “If pollinator declines continue at this rate it will have serious implications not just for human food security and economics but also for biodiversity and the health of ecosystems in general … When we lose even one pollinator species from an ecosystem, it can degrade the functioning of the system overall … Studies have shown this relationship between biodiversity of pollinators and both agricultural productivity and plant reproduction in wild ecosystems … Nutritionally, the pollinator declines will likely have the biggest impact on the poorest people of the world” (quoted in Clark‐Emory 2016). Beyond nutritional issues, pollinators are needed for crops that are the source of biofuels (e.g., canola and palm oils), fibers (e.g., cotton and linen), forage for livestock, and construction materials like wood.

      2.3.3 Regional and planet‐wide natural interconnecting structures

      The water cycle is the constant movement of water on, in, and above Earth (U.S. Geological Survey 2016). On the planet’s surface, water appears as rivers and streams, ponds, swamps, dew, and oceans, and in frozen form as land and sea ice, all of which are connected through their flows, by precipitation, and by water coursing under the ground in vast quantities in spaces between rocks and subsurface soils and in aquifers. Some precipitation makes its way downward into groundwater. There is also ice found underground in caverns and ice tubes. Fresh water (about half of which is as salty as sea water) is even found in subterranean pools 600 feet under the Atlantic Ocean. Above the planet, the atmosphere is a superhighway of water vapor that moves around the globe. When, during its movement, water vapor encounters cooler temperatures, it condenses to form clouds, which are pushed around by strong winds until the vapor falls to Earth as rain or snow. About 90 percent of the water vapor in the atmosphere is produced by evaporation from water bodies, while the remainder comes from the release of moisture by plants—a process known as transpiration. The oceans are the source of 90 percent of water evaporation that flows into the planetary water cycle. While they are the primary location of water storage on Earth—currently estimated to hold 321 000 000 cubic miles—they vary in volume over time due to climate change, as we see today with rising sea levels due to land ice melt and the increased mobility of molecules in warmer water. Within the oceans, currents like the Gulf Stream move immense amounts of water around the world.

      The interconnection of global flows like the jet stream


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