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Soil Conference

Submitted by nskinner on Mon, 11/18/2019 - 20:59

There is a relationship between the texture of the soil and hydraulic conductivity. That relationship revolves around matric potential. At saturated conditions, hydraulic conductivity is much higher than potentials that are in unsaturated conditions. When there is a high moisture content, the hydraulic conductivity is higher in the sand than in the clay. At low moisture contents hydraulic conductivity is higher in the clay rather than sand. This phenomena occurs because sand has many more macropores and this allows moisture to move readily through the soil. That is why the graph shows the sandy loam soil’s curve dropping faster than the clay. Saturated flow takes place near zero ksat. This can be seen on the graph just before the sandy loam’s line starts to curve downward. In unsaturated conditions, the sandy loam ksat decreases. For the clay soil, the ksat is high in unsaturated conditions. This most likely has to do with the many more small pores that clay has versus sandy loams with macropores.

Methods to Plant Ecology

Submitted by nskinner on Sun, 11/17/2019 - 19:54

To determine if there are different sized trees in different habitats we measure the diameter at breast height (dbh) of trees on a north facing slope, south facing slope and a flat. Each location was at the Mount Holyoke Range in Amherst, Massachusetts. Each site differed in steepness and direction of slope, but not longitude of latitude. The sites were located near a point on the ridge referred to as “The Notch.” This location is also where highway 116 crosses the notch. At each site, the dbh (measured to the nearest 0.1cm), and the species of each live adult tree was measured.

Plant Ecology Perfect Paragraph

Submitted by nskinner on Sun, 11/17/2019 - 19:41

The steepness of a slope is an abiotic factor of the microclimate and habitat of that area. Slope aspects such as potential energy income can differ between steeper and less steep slopes (Méndez, Meave, Zermeño, Ibarra, Woods, 2016). Significant difference between individual sizes of vegetation can be found on different slopes. Although this can be due to the south facing slopes getting higher incidence of solar radiation, it could also be due to the potential energy income of larger trees on a slope versus smaller trees. If this is the case then both north and south facing slopes should have smaller trees if the slope is steeper. The larger trees of the same species are generally older than the smaller trees of the same species and this can idea can help make an inference on mortality rates of a species if there are more small trees in a given area than large ones.

Abstract Draft

Submitted by nskinner on Wed, 11/13/2019 - 19:26

To determine whether different habitats have different sized trees, we measured the diameter at breast height (dbh) of adult trees in three sites at the Holyoke Range in Amherst Massachusetts. The sites included a north slope, south slope and flat area at an area called  “The Notch” on the range. The dbh of these trees was used to find basal area of the adult trees present in eight replicates. After analyzing the basal area of adult trees it was determined that the average basal area was not that different between the slopes. The species Quercus rubra/velutina was also specifically looked at because of its high density at each site compared to other species. It was predicted that the basal area of this species would be larger on the flat than on either north or south slopes. It was actually found that the north slope have higher average basal area than either the flat of the south slopes. Ultimately, the results did not support the hypothesis that steeper slopes have small trees due to higher mortality rates of of larger trees.

Plant Ecology Perfect Paragraph

Submitted by nskinner on Wed, 11/13/2019 - 19:19

The stability of slopes is correlated with the vegetation on that slope in regards to stability (Fan, Lai 2104). The root systems of plants play a pivotal role in the stability of a slope. Does the slope also determine what vegetation is present and for how long? This idea my help determine if trees in different habitats tend to be different sizes. The steepness of a slope can create different habitats. The difference in these habitats can be related to the variance in the steepness of slopes. It is well known that generally the larger the radial measurement of a tree is the older that tree is. A series of small trees could indicate information about the mortality rate of that species. Mortality rates may depend on the slope steepness and elevation (Bigler, 2016). This notion can be related back to the variance in tree size and certain habitats. Steeper slopes have smaller trees due to higher mortality rates of larger trees.

Plant Ecology

Submitted by nskinner on Wed, 11/13/2019 - 19:17

The stability of slopes is correlated with the vegetation on that slope in regards to stability (Fan, Lai 2104). The root system of plants play a pivotal role in the stability of a slope, but does the slope also determine what vegetation is present and for how long? This idea my help determine if trees in different habitats tend to be different sizes. The steepness of a slope can create different habitats. The difference in these habitats can be related to the variance in the steepness of slopes. It is well known that generally the larger the radial measurement of a tree is the older that tree is. A series of small trees could indicate information about the mortality rate of that species. Mortality rates may depend on the slope steepness and elevation (Bigler, 2016). This notion can be related back to the variance in tree size and certain habitats. Steeper slopes have smaller trees due to higher mortality rates of larger trees.

Seed Germination

Submitted by nskinner on Fri, 11/08/2019 - 09:45

The seed coat is designed to allow a seed to survive in conditions that would have been intolerable to the adult plant. The seed is able to wait until suitable environmental conditions occur before germination (Sanford, 1963). In most cases, seeds can be germinated in moist substrate that is stored in dim light or even dark. The temperature can be 15-30℃.Germination rates can occur between 16 hours and up to 10 days in most cases (Sanford, 1963).

Hydraulic Conductivity

Submitted by nskinner on Thu, 11/07/2019 - 08:21

There is a relationship between the texture of the soil and hydraulic conductivity. That relationship revolves around matric potential. At saturated conditions, hydraulic conductivity is much higher than potentials that are in unsaturated conditions. When there is a high moisture content, the hydraulic conductivity is higher in the sand than in the clay. At low moisture contents hydraulic conductivity is higher in the clay rather than sand. This phenomena occurs because sand has many more macropores and this allows moisture to move readily through the soil. That is why the graph shows the sandy loam soil’s curve dropping faster than the clay. Saturated flow takes place near zero ksat. This can be seen on the graph just before the sandy loam’s line starts to curve downward. In unsaturated conditions, the sandy loam ksat decreases. For the clay soil, the ksat is high in unsaturated conditions. This most likely has to do with the many more small pores that clay has versus sandy loams with macropores.

Soil Conference

Submitted by nskinner on Wed, 11/06/2019 - 09:53

The overall theme of the talk was about a case study on the East Transport Water System which is a public drinking water system. The Portsmouth Regional and Pease International trade water system is owned and operated by the city of Portsmouth. For many years the area was actually an Air Force base where fire retardants were tested in fire training. After the Air Force base was shut down, the property was returned to the community where 250 businesses, some including daycares were established. There were 3 wells, all manifolded and all go to the one Pease site. In May of 2014, PFAS compounds were found near the Air Force base location at Pease. It was 2500 ppt. That well was immediately shut down. Portsmouth water had to supplement that water supply.

Cranberry Flowering Time Perfect Paragraph

Submitted by nskinner on Fri, 11/01/2019 - 21:56

Research has shown that cultivated cranberries react to warmer temperatures by flowering earlier; just as wild flowers do. This has critical implications to both cultivators and symbiotic species that utilize cranberries in Massachusetts. Cultivators face challenges by the earlier flowering of cranberries. The effect of phenology alteration due to climate change is also important when considering the relationship between pollinators and plants. Using controlled and well recorded cranberry bogs in Massachusetts can help understand the processes of earlier flowering times throughout the world.

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