Spelling suggestions: "subject:"blackland"" "subject:"lackland""
1 |
Analysis Of Conservation Practices In The Blackland Prairie Region Of Mississippi And Construction Of A Predictor For Locating New Sites For Conservation EffortsHughes, Steven Cameron 30 April 2011 (has links)
Mississippi’s Blackland Prairie has been reduced below 10% of pre-Columbian extent, with few conservation practices in place. To determine efficacy of current restoration practices, plant species at remnant sites were compared with those at restoration sites. Analyses using multivariate statistical approaches revealed no generalizable patterns among four available remnants versus two available restoration sites. Thus, the aim of this project shifted to evaluating methods of identifying Blackland Prairie remnants or potential restoration sites. Location data for Blackland Prairie plant species and potentially informative environmental variables were used to develop geographic information system (GIS)-based habitat models. The best models were selected for validation against a second set of data collected from random points on public lands across the survey region. Validation surveys also were used to explore trends in predictive success and to aid in increasing accuracy through inclusion of other variables. Models incorporating soil characteristics had the highest predictive success.
|
2 |
Developing and Testing a Trafficability Index for Planting Corn and Cotton in the Texas Blackland PrairieHelms, Adam J. 2009 December 1900 (has links)
The Texas Blackland Prairie is one of the most productive agricultural regions in
Texas. This region provides a long growing season coupled with soils that have a high
water holding capacity. However, the soils also provide significant challenges to
producers because the high water holding capacity is a product of a high clay percentage.
This research was aimed to develop and test an expert-based trafficabililty index, based
upon soil moisture, for planting cotton (Gossypium hirsutum L.) and corn (Zea mays L.)
on the Texas Blackland Prairie. Testing the index focused on quantify the potential
effect of high soil moisture at planting on seed furrow sidewall compaction and
associated plant growth response. Once the trafficability index was developed, three
workable soil moisture regimes were recreated in no-tillage and conventional tillage
plots at the Stiles Farm Foundation in Thrall, Texas. The index nomenclature included:
"Dry-Workable", "Optimal" and "Wet-Workable". After planting corn and cotton into
conventional and no tillage plots, 0.45 x 0.20 x 0.15 m intact soil blocks were removed
from each plot and kept in a controlled environment. At 28 days, each block was
destructively harvested to quantify plant root and shoot growth responses. Each of the three soil moisture indexes was replicated thrice per crop, and the whole experiment was
replicated twice in time, n = 48 blocks.
The trafficability index was created using three producer experts, and over 10
interviews to collect a range in soil moisture samples. From "Wet Workable" to "Dry
Workable", the gravimetric soil moistures were 0.17, 0.22, and 0.26 g g-1. For corn and
cotton, a positive relationship between plant growth factors and planting at soil moisture
existed. Plants planted at the highest soil moisture emerged faster and developed more
root and shoot biomass than those planted at the lowest soil moisture. No evidence of a
detrimental plant response because of seed furrow, sidewall compaction from planting at
too high a soil moisture content could be quantified. Furthermore, the cotton plants in
no-tillage performed better than in conventional tillage, but corn performed better in
conventional tillage. Because the results showed an advantage to plant growth by
planting in the "Wet Workable" index, the tillage practice that allows the producer to
enter the field with a planter at higher moisture contents appears to have an advantage.
|
3 |
Indirect effects of fire on the small mammal community of a tallgrass blackland prairie remnant in TexasKirchner, Brianna N. Wilkins, Kenneth T. January 2009 (has links)
Thesis (M.S.)--Baylor University, 2009. / Includes bibliographical references (p. 65-71).
|
4 |
Managing iron deficiency chlorosis (IDC) in soybean through a cropping system approachWaldrep, Katelin Savannah 12 May 2023 (has links) (PDF)
Iron deficiency chlorosis (IDC) is a frequent problem throughout many areas of the United States where soils are high in calcium carbonate (CaCO3), including the Blackland Prairie regions of Mississippi. The main objectives of this study were to 1) determine the effects of seven different cropping systems on IDC visual symptomology and grain yield in rainfed soybeans grown in calcareous soils, and 2) evaluate the effects of soil water tension (SWT) on IDC. Rotating soybeans with corn produced significantly higher yields for both tolerant and susceptible soybean varieties. IDC symptomology was worse, and yields were lower in cropping systems with lower average SWT, or wetter soils, throughout the growing season. Last, this study evaluated the use of multispectral imagery and apparent soil electrical conductivity (ECa) to identify IDC-prone areas of a field for the site-specific implementation of management strategies that produced higher yields in the plot-scale study.
|
Page generated in 0.0262 seconds