Vegetation indicators for terrain evaluation in a prairie environment

1977 ◽  
Vol 14 (4) ◽  
pp. 445-465 ◽  
Author(s):  
E. Karl Sauer ◽  
E. A. Wilson
Keyword(s):  
Soil Moisture ◽  
Plant Communities ◽  
Significant Contribution ◽  
Surface Soil ◽  
Wide Band ◽  
Black Soil ◽  
Soil Horizon ◽  
Individual Species ◽  
Moisture Conditions ◽  
Geomorphic Units

Natural vegetation can be a useful indicator of terrain conditions and thus has significant geotechnical implications especially in identifying moisture, groundwater conditions, and strati-graphic changes. A pilot study was initiated to study physiographic, climatic, biotic, and compensating factors as they affect plant communities in the Langham area, near Saskatoon, Saskatchewan. The study area is located at the transition between the Dark Brown and Black Soil Zones, which are colour zones of the surface soil horizon as influenced by climate and vegetation. It is suggested that the findings at Langham can be extrapolated over a wide band across the province where the soil zones and geomorphic units are similar. It was found that trees or shrubs are more reliable indicators of soil moisture conditions than low-growing plants and that plant communities are better indicators than individual species. In some places, the recognition of changes in vegetation patterns could make a significant contribution to geotechnical projects. A direct correlation was found between the number of species occurring in a plant community and soil moisture conditions. Drier sites had fewer species.

scholarly journals A new data assimilation approach for improving runoff prediction using remotely-sensed soil moisture retrievals

2009 ◽  
Vol 13 (1) ◽  
pp. 1-16 ◽  
Author(s):  
W. T. Crow ◽  
D. Ryu
Keyword(s):  
Soil Moisture ◽  
Data Assimilation ◽  
Surface Runoff ◽  
Surface Soil ◽  
Remotely Sensed ◽  
Hydrologic Model ◽  
Surface Soil Moisture ◽  
Antecedent Soil Moisture ◽  
Runoff Prediction ◽  
Moisture Conditions

Abstract. A number of recent studies have focused on enhancing runoff prediction via the assimilation of remotely-sensed surface soil moisture retrievals into a hydrologic model. The majority of these approaches have viewed the problem from purely a state or parameter estimation perspective in which remotely-sensed soil moisture estimates are assimilated to improve the characterization of pre-storm soil moisture conditions in a hydrologic model, and consequently, its simulation of runoff response to subsequent rainfall. However, recent work has demonstrated that soil moisture retrievals can also be used to filter errors present in satellite-based rainfall accumulation products. This result implies that soil moisture retrievals have potential benefit for characterizing both antecedent moisture conditions (required to estimate sub-surface flow intensities and subsequent surface runoff efficiencies) and storm-scale rainfall totals (required to estimate the total surface runoff volume). In response, this work presents a new sequential data assimilation system that exploits remotely-sensed surface soil moisture retrievals to simultaneously improve estimates of both pre-storm soil moisture conditions and storm-scale rainfall accumulations. Preliminary testing of the system, via a synthetic twin data assimilation experiment based on the Sacramento hydrologic model and data collected from the Model Parameterization Experiment, suggests that the new approach is more efficient at improving stream flow predictions than data assimilation techniques focusing solely on the constraint of antecedent soil moisture conditions.

Infiltrometer studies in rangeland plant communities of the Northern Territory.

1978 ◽  
Vol 1 (2) ◽  
pp. 142 ◽  
Author(s):  
GF Gifford
Keyword(s):  
Soil Moisture ◽  
Plant Communities ◽  
Flood Plain ◽  
Northern Territory ◽  
Infiltration Process ◽  
Antecedent Soil Moisture ◽  
Soil Movement ◽  
Sediment Yields ◽  
Moisture Conditions ◽  
The Impact

Infiltrometer studies were conducted within several plant communities near Alice Springs, Northern Territory. Plant commu- nities studied included mulga-perennial, mulga-shortgrass, savanna woodland, gilgai, flood-plain grassland, and scalded areas (no vegetation). Attempts were made to quantify the impact of surface crusting, antecedent soil moisture conditions, and time of year on infiltration rates and potential sediment yields. Results indicate that the infiltration process within certain plant communities is often complex, and hydrologic differences which occur both within and among the plant communities should be acknowledged. Sediment yields from a floodplain-grassland unit and a scald situation were about 2 and 5 times greater, respectively, than those from various mulga communities, woodland, or gilgai circumstances. With one exception, antecedent soil moisture had little influence on sediment yields. Removal of surface soil crusts significantly increased sediment yields, regardless of antecedent soil moisture conditions. The relationship between soil movement and loss and ecosystem stability needs to be established for most rangeland environments, but little has been done to satisfy this need.

scholarly journals Streamside management zone (SMZ) efficiency in herbicide retention from simulated surface flow

2008 ◽  
Vol 26 (1) ◽  
pp. 131-142
Author(s):  
A.T. Matos ◽  
A.P. Pinho ◽  
L.M. Costa ◽  
L.A. Morris
Keyword(s):  
Soil Moisture ◽  
Overland Flow ◽  
Surface Flow ◽  
Soil Horizon ◽  
Wet Season ◽  
Measured Variable ◽  
Streamside Management Zones ◽  
Simulated Surface ◽  
Moisture Conditions ◽  
Over The Top

Plot-scale overland flow experiments were conducted to evaluate the efficiency of streamside management zones (SMZs) in retaining herbicides in runoff generated from silvicultural activities. Herbicide retention was evaluated for five different slopes (2, 5, 10, 15, and 20%), two cover conditions (undisturbed O horizon and raked surface), and two periods under contrasting soil moisture conditions (summer dry and winter wet season) and correlated to O horizon and site conditions. Picloram (highly soluble in water) and atrazine (moderately sorbed into soil particles) at concentrations in the range of 55 and 35 µg L-1 and kaolin clay (approximately 5 g L-1) were mixed with 13.000 liters of water and dispersed over the top of 5 x 10 m forested plots. Surface flow was collected 2, 4, 6, and 10 m below the disperser to evaluate the changes in concentration as it moved through the O horizon and surface soil horizon-mixing zone. Results showed that, on average, a 10 m long forested SMZ removed around 25% of the initial concentration of atrazine and was generally ineffective in reducing the more soluble picloram. Retention of picloram was only 6% of the applied quantity. Percentages of mass reduction by infiltration were 36% for atrazine and 20% for picloram. Stronger relationships existed between O horizon depth and atrazine retention than in any other measured variable, suggesting that better solid-solution contact associated with flow through deeper O horizons is more important than either velocity or soil moisture as a determinant of sorption.

scholarly journals A new data assimilation approach for improving hydrologic prediction using remotely-sensed soil moisture retrievals

2008 ◽  
Vol 5 (4) ◽  
pp. 2005-2044 ◽  
Author(s):  
W. T. Crow ◽  
D. Ryu
Keyword(s):  
Soil Moisture ◽  
Data Assimilation ◽  
Surface Runoff ◽  
Surface Soil ◽  
Remotely Sensed ◽  
Hydrologic Model ◽  
Surface Soil Moisture ◽  
Antecedent Soil Moisture ◽  
Hydrologic Prediction ◽  
Moisture Conditions

Abstract. A number of recent studies have focused on enhancing hydrologic prediction via the assimilation of remotely-sensed surface soil moisture retrievals into a hydrologic model. The majority of these approaches have viewed the problem from purely a state or parameter estimation perspective in which remotely-sensed soil moisture estimates are assimilated to improve the characterization of pre-storm soil moisture conditions in a hydrologic model, and consequently, its simulation of runoff response to subsequent rainfall. However, recent work has demonstrated that soil moisture retrievals can also be used to filter errors present in satellite-based rainfall accumulation products. This result implies that soil moisture retrievals have potential benefit for characterizing both antecedent moisture conditions (required to estimate sub-surface flow intensities and subsequent surface runoff efficiencies) and storm-scale rainfall totals (required to estimate the total surface runoff volume). In response, this work presents a new sequential data assimilation system that exploits remotely-sensed surface soil moisture retrievals to simultaneously improve estimates of both pre-storm soil moisture conditions and storm-scale rainfall accumulations. Preliminary testing of the system, via a synthetic twin data assimilation experiment based on the Sacramento hydrologic model and data collected from the Model Parameterization Experiment, suggests that the new approach is more efficient at improving stream flow predictions than data assimilation techniques focusing exclusively on the constraint of antecedent soil moisture conditions.

scholarly journals Plant communities and associations of root crops of the Kałuszyńska Upland

2012 ◽  
Vol 61 (2) ◽  
pp. 121-129
Author(s):  
Teresa Skrajna ◽  
Janina Skrzyczyńska
Keyword(s):  
Soil Moisture ◽  
Plant Communities ◽  
Floristic Diversity ◽  
Setaria Viridis ◽  
Root Crops ◽  
Weed Communities ◽  
Moisture Conditions

A phytosociological classification and the characteristics of weed communities developing in root crops of the Kałuszyńska Upland are given in this paper. The presence of three associations: <i>Digitarietum ischaemi</i>, <i>Echinochloo-Setarietum</i> and <i>Lamio-Veronicetum politae</i>, as well as of two communities: <i>Setaria pumila</i>-<i>Setaria viridis</i> and <i>Panico-Setarion</i> alliance, has been found. The differentiation in trophic and soil moisture conditions of habitats results in the floristic diversity of communities, divided into lower phytosociological units. Two variants have been distinguished within the association <i>Digitarietum ischaemi</i>, whereas <i>Echinochloo-Setarietum</i> has been divided into 2 subassociations and 6 variants.

Evaluation of Presswheels and Seed Coverers for Direct Seeding of Brassica

HortScience ◽  
1997 ◽  
Vol 32 (4) ◽  
pp. 599E-600
Author(s):  
Regina P. Bracy ◽  
Richard L. Parish
Keyword(s):  
Soil Moisture ◽  
Sandy Loam ◽  
Visual Observation ◽  
Mustard Seed ◽  
High Soil Moisture ◽  
Loam Soil ◽  
Direct Seeded ◽  
Plant Emergence ◽  
Moisture Conditions ◽  
Determine Effect

Improved stand establishment of direct-seeded crops has usually involved seed treatment and/or seed covers. Planters have been evaluated for seed/plant spacing uniformity, singulation, furrow openers, and presswheel design; however, effects of presswheels and seed coverers on plant establishment have not been widely investigated. Five experiments were conducted in a fine sandy loam soil to determine effect of presswheels and seed coverers on emergence of direct-seeded cabbage and mustard. Seed were planted with Stanhay 870 seeder equipped with one of four presswheels and seed coverers. Presswheels included smooth, mesh, concave split, and flat split types. Seed coverers included standard drag, light drag, paired knives, and no coverer. Soil moisture at planting ranged from 8% to 19% in the top 5 cm of bed. Differences in plant counts taken 2 weeks after planting were minimal with any presswheel or seed coverer. Visual observation indicated the seed furrow was more completely closed with the knife coverer in high soil moisture conditions. All tests received at least 14 mm of precipitation within 6 days from planting, which may account for lack of differences in plant emergence.

Sign in / Sign up

Export Citation Format

Share Document