scholarly journals Predictive Models for Reforestation and Agricultural Reclamation: A Clearfield County, Pennsylvania Case Study

2021 ◽  
Author(s):  
Zhi Yue ◽  
Jon Bryan Burley
Keyword(s):  
Predictive Model ◽  
Red Clover ◽  
Red Maple ◽  
Government Officials ◽  
White Pine ◽  
Rock Fragments ◽  
White Ash ◽  
Agronomic Crops ◽  
Interaction Terms

Natural resource scientists, concerned citizens, and government officials are interested in reconstructing disturbed environments for reforestation and agricultural productivity. We examined Clearfield County in Pennsylvania, USA, to develop a predictive model to reconstruct the landscape for seven agronomic crops (corn, corn silage, oats, alfalfa hay, red clover, bluegrass, and soybeans) and thirteen woody plants (white cedar, lilac, highbush cranberry, Amur maple, gray dogwood, peashrub, white spruce, white pine, red maple, red pine, jack pine, nannyberry, and white ash). A significant predictive model (p ≤ 0.001) was generated explaining 96.94% of the variance, with percent clay, bulk density, hydraulic conductivity, available water capacity, pH, percent organic matter, percent rock fragments, slope, topographic position, and electrical conductivity explored as main effect terms, plus squared terms, and first order interaction terms. The model is not over-specified and each predictor is significant (p ≤ 0.05). The modeling effort suggests that there are at least several clusters of vegetation preference dimensions based upon the terrain of the landscape. The model provides insight into how to reconstruct the disturbed environment for vegetation in the study area.

Thinning in mature eastern white pine: 43-year case study

2002 ◽  
Vol 78 (4) ◽  
pp. 539-549 ◽  
Author(s):  
Paul D Anderson ◽  
John C Zasada ◽  
Glen W Erickson ◽  
Zigmond A Zasada
Keyword(s):  
Genetic Diversity ◽  
Dna Analysis ◽  
Large Diameter ◽  
White Pine ◽  
Thinning Intensity ◽  
Pine Regeneration ◽  
Volume Production ◽  
Pine Stands ◽  
Over Time

A white pine (Pinus strobus L.) stand at the western margin of the species range, approximately 125 years of age at present, was thinned in 1953 from 33.5 m2 ha-1 to target residual basal areas of 18.4, 23.0, 27.5, and 32.1 m2 ha-1 . Repeated measurement over the following 43-years indicated that the greatest total volume production and the greatest number of large diameter trees occurred in the unit of highest residual density. Over time, the distribution of stems was predominantly random although mortality between 1979 and 1996 resulted in a tendency for clumping in the 23.0 and 27.5 m2 ha-1 treatments. DNA analysis indicated that thinning intensity had little effect on the genetic diversity of residual white pine. This study suggests that mature white pine stands in northern Minnesota may be managed at relatively high densities without loss of productivity. However, regardless of overstory density, there was little or no white pine regeneration occurring in this stand. Key words: thinning, growth, genetic diversity, molecular markers, spatial pattern, regeneration

Growth responses of seven major co-occurring tree species of the northeastern United States to elevated CO2

1990 ◽  
Vol 20 (9) ◽  
pp. 1479-1484 ◽  
Author(s):  
F. A. Bazzaz ◽  
J. S. Coleman ◽  
S. R. Morse
Keyword(s):  
Tree Species ◽  
Sugar Maple ◽  
Growth Enhancement ◽  
Black Cherry ◽  
Red Maple ◽  
Growth Responses ◽  
White Pine ◽  
American Beech ◽  
Harvard Forest ◽  
Paper Birch

We examined how elevated CO2 affected the growth of seven co-occurring tree species: American beech (Fagusgrandifolia Ehrh.), paper birch (Betulapapyrifera Marsh.), black cherry (Prunusserotina Ehrh.), white pine (Pinusstrobus L.), red maple (Acerrubrum L.), sugar maple (Acersaccharum Marsh.), and eastern hemlock (Tsugacanadensis (L.) Carr). We also tested whether the degree of shade tolerance of species and the age of seedlings affected plant responses to enhanced CO2 levels. Seedlings that were at least 1 year old, for all species except beech, were removed while dormant from Harvard Forest, Petersham, Massachusetts. Seeds of red maple and paper birch were obtained from parent trees at Harvard Forest, and seeds of American beech were obtained from a population of beeches in Nova Scotia. Seedlings and transplants were grown in one of four plant growth chambers for 60 d (beech, paper birch, red maple, black cherry) or 100 d (white pine, hemlock, sugar maple) under CO2 levels of 400 or 700 μL•L−1. Plants were then harvested for biomass and growth determinations. The results showed that the biomass of beech, paper birch, black cherry, sugar maple, and hemlock significantly increased in elevated CO2, but the biomass of red maple and white pine only marginally increased in these conditions. Furthermore, there were large differences in the magnitude of growth enhancement by increased levels of CO2 between species, so it seems reasonable to predict that one consequence of rising levels of CO2 may be to increase the competitive ability of some species relative to others. Additionally, the three species exhibiting the largest increase in growth with increased CO2 concentrations were the shade-tolerant species (i.e., beech, sugar maple, and hemlock). Thus, elevated CO2 levels may enhance the growth of relatively shade-tolerant forest trees to a greater extent than growth of shade-intolerant trees, at least under the light and nutrient conditions of this experiment. We found no evidence to suggest that the age of tree seedlings greatly affected their response to elevated CO2 concentrations.

Impact of Deer Browsing on Regeneration in Mixed Stands in Southern New England

1995 ◽  
Vol 12 (3) ◽  
pp. 115-120 ◽  
Author(s):  
David B. Kittredge ◽  
P. Mark S. Ashton
Keyword(s):  
New England ◽  
Tree Species ◽  
Sugar Maple ◽  
Red Maple ◽  
White Pine ◽  
Mixed Stands ◽  
Tree Species Composition ◽  
Southern New England ◽  
Pine Seedlings ◽  
Species Specific

Abstract Browsing preferences by white-tailed deer were evaluated for 6 tree species in northeastern Connecticut. Deer density averaged 23/mile². Deer exhibited no species-specific preferences for seedlings greater than 19 in. For seedlings less than 19 in., hemlock and black birch were preferred. Red maple, sugar maple, and white pine seedlings were avoided. Red oak seedlings were neither preferred nor avoided. A much higher proportion of seedlings greater than 19.7 in. in height was browsed, regardless of species. Browsing preferences for species in the smaller seedling class, combined with a lack of preference for species in the larger class may result in future stands with less diverse tree species composition. Deer densities in excess of 23/mile² may be incompatible with regeneration of diverse forests in southern New England. North. J. Appl. For. 12(3):115-120.

Food Security as Correlate of Interstate Conflict: A Case Study of the State of Qatar

2021 ◽  
pp. 1-15
Author(s):  
Farukh Mohammad Azad ◽  
Dr. Tim Frazier ◽  
Erik Wood
Keyword(s):  
Food Security ◽  
Food Insecurity ◽  
Relevant Literature ◽  
The State ◽  
Interstate Conflict ◽  
Regulatory Agencies ◽  
Political Crisis ◽  
Government Officials ◽  
Sequential Mixed Methods

The literature indicates that conflict can result in food insecurity due to economic or political crisis. However, few studies have investigated the effects that nonviolent interstate conflict has on food security in the Middle East. Evidence from this study, based in Qatar, indicates that conflict can result in food insecurity due to economic or political crisis. This research critically examines the lingering political and economic blockade of the State of Qatar and the extent to which this blockade has impacted food security of residents. The study employed a sequential mixed methods approach to gain better insight into the nature of food security in Qatar. A focused qualitative review of the relevant literature was followed by a quantitative analysis which revealed that there was no significant effect of interstate conflict on food security, while the economic and political blockade correlated significantly with food security. Three groups were sampled, including government officials, regulatory agencies, and food suppliers.

Preventing post-disaster population losses and recovery policy

2021 ◽  
Vol 19 (3) ◽  
pp. 240-244
Author(s):  
Joseph L. Richmond, LPD, MPA
Keyword(s):  
Future Research ◽  
Government Officials ◽  
Specific Policy ◽  
Business Officials ◽  
Recovery Processes ◽  
Response And Recovery ◽  
Policy Measures ◽  
Design Case Study ◽  
The City

Objective: On May 22, 2011, an EF-5 tornado struck Joplin, Missouri, leaving behind 161 fatalities and $2.8 billion in economic impacts. This case study of the 2011 disaster was an attempt at determining if and how economic recovery occurred following the disaster through the lived experiences of government officials, local policymakers, and business officials. Design: Case study using in-depth, semistructured, one-on-one interviews and a qualitative design and analysis.Setting: Joplin, Missouri/2011 Joplin Tornado Participants: Seven local government officials, policymakers, and business officials from the city of Joplin that were directly involved in the response and recovery from the 2011 tornado.Interventions: N/AMain outcome measure(s): N/AResults: Policies and actions that were the most effective focused on housing, personal financial resources of the survivors, and ensuring that the recovery processes were expedited as much as prudently possible.Conclusions: Specific policy measures are not recommended through the un-generalizable findings of this case study; however, this case study places a foundation for future research to develop specific policy measures related to disaster recovery.

Towards a predictive model for polymer solubility using the noncovalent interaction index: polyethylene as a case study

2021 ◽  
Author(s):  
Mats Denayer ◽  
Jelle Vekeman ◽  
Frederik Tielens ◽  
Frank De Proft
Keyword(s):  
Predictive Model ◽  
Noncovalent Interaction ◽  
Intramolecular Interactions ◽  
Interaction Index ◽  
Covalent Interaction ◽  
Polymer Solubility

A novel solubility descriptor is presented based on the non-covalent interaction index, providing information on the solute’s inter- and intramolecular interactions, and its conformation. Polyethylene in (anti)solvent is used as a case-study.

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