Blackwater River Shed and Pleasant Lake

Friday September 21, 2012
E block AP Environmental Science
Today our class, taught by the stupendous Alan McIntyre, took a short field trip to the Blackwater River Shed and Pleasant lake.  While at the lake Alan discussed the differences between abiotic and biotic life forms, the cycle of energy and life, evolution in these niches, and diversity in a niche.

The abiotic, or non-living, aspects of the environment are the foundation for life.  The rocks, soil, sediment, sand, and water generate and store nutrients and chemicals necessary for life.  "If it weren't for the abiotic things that carry nutrients and chemicals it would not be possible for the water to flow and life would not be possible" said McIntyre.  These abiotic systems are the foundation for life on our planet.

Biotic, or living, things in the environment are natural responses to the abiotic system.  These living things we observed on our trip are perfect examples of how life formed on our planet.  The glacier melted, the water runs down the river collecting nutrients from the abiotic things in the area, organisms feed and live on these nutrients, other things feed and grow using the original organisms as nutrition, etc. These organisms live not only off the abiotic nutrients but also off of each other.

The water cycle is necessary for life because it filters and moves water through the air and ground.  Every part of the water cycle is dependent on eachother. The river would not flow if there was no rain coming from the mountains, there would be no condensation if the water did not evaporate from the lake and river, and there would be no rain if the evaporated water did not condensate in the air.  The water cycle moves nutrients from the hills down through to the river giving life to everything around it.

Diversity of nutrients and chemicals makes life possible in different ways.  Different nutrients benefit life in different ways, life in the lake is different from in the river because there is 1 part phosphorus per million in the lake and 1.5 ppm of phosphorus in the river.  The amount of phosphorous gives different benefits to different organisms making these areas very diverse.

Energy is transferred through the movement of water picking up nutrients and fueling plants etc.  If the water did not flow through the river there would not be a movement of energy and therefore not any life.  The sun gives off energy as well, making heat is a main source of life on the planet.

Evolution has created the ecosystem we see today.  Things thrive off of the river and lake and grow and evolve to be at the peak of being able to survive in the conditions they are in.  If not for the evolution of organisms the ecosystem would have stopped growing and changing and supporting more life and different life forms.

Pleasant Lake

Pleasant Lake is the largest source of water in the area and it flows down into the Blackwater River and to the River Shed.  "This lake was formed 12,000 years ago when a 500 foot glacier sat over this whole area." said Alan McIntyre. After that glacier melted the water collected in the area and moss and lichen grew on rocks next to the lake as well as the river that was flowing from the lake. The melting of the glacier created a "system because it is constantly taking water from the highlands and moving to low land" which prevents from algae build up and moves water to places where other organisms can thrive.  "when it rains the water rolls down the mountains and collects in the watershed or lake."  The water moving through the soil, sand, and rocks in the mountains transports vital chemicals and minerals for life in the lake and river.  Nitrogen and phosphorus are two of the main sources for life that are in these waters.

Blackwater River

Blackwater River watershed in Andover, New Hampshire is a flourishing Deciduous forest with the Blackwater River running through it. This river was created by runoff from mountains and from Pleasant Lake that collected at the lowest point and flows down from the hills.  The rocks, sediment, sand, and dirt create an environment rich in nutrients for plants to grow and animals to live in.  The moving water prevents algae from over covering the top of the water, which ensures sunlight to get to the ground under it making it possible for fish and other organisms to live.  The Blackwater River is the engine that runs the environment around it.

River water Ph color

Lake water Ph color

On this trip the air temperature was 52 degrees Fahrenheit. The water at the Blackwater River Shed was 57.2 degrees Farenheit. The water in Pleasant Lake was 65 degrees Farenheit. The water in the lake was warmer than the water in the river because it is standing water which can absorb and store more solar radiation (heat energy). The moving water in the river is constantly ducking away from sunlight and not taking in heat.  The lake also had a higher acidic value as demonstrated by the Ph value of 6.5-7 than its counterpart 6-6.5 range of the river water.  In both cases they were extremely close to the non-acidic range and both the lake and river are considered class C water masses (best for swimming, boating, etc.).