Long-Term Effectiveness of Tree Removal to Re-Establish Sagebrush Steppe Vegetation and Associated Spatial Patterns in Surface Conditions and Soil Hydrologic Properties

Pinyon (Pinus spp.) and juniper (Juniperus spp.) woodland encroachment into sagebrush (Artemisia spp.) steppe communities throughout western North America has substantially altered the vegetation structure and hydrologic function of one of the most ecologically important rangeland ecosystems in the world. Various pinyon and juniper tree removal practices are employed to re-establish sagebrush steppe vegetation and an associated resource-conserving ecohydrologic function. The effectiveness of these practices is highly variable owing to the vast domain in which woodland encroachment occurs, climate fluctuations, differences in treatment applications, and myriads of pre-treatment conditions and post-treatment land uses. This study evaluated the long-term (13 years post-treatment) effectiveness of prescribed fire and mechanical tree removal to re-establish sagebrush steppe vegetation and associated spatial patterns in ground surface conditions and soil hydrologic properties of two woodland-encroached sites. Specifically, we assessed the effects of tree removal on: (1) vegetation and ground cover at the hillslope scale (990 m2 plots) and (2) associated spatial patterns in point-scale ground surface conditions and soil hydrologic properties along transects extending from tree bases and into the intercanopy areas between trees. Both sites were in mid to late stages of woodland encroachment with extensive bare conditions (~60–80% bare ground) throughout a degraded intercanopy area (~75% of the domain) surrounding tree islands (~25% of domain, subcanopy areas). All treatments effectively removed mature tree cover and increased hillslope vegetation. Enhanced herbaceous cover (4–15-fold increases) in burned areas reduced bare interspace (bare area between plants) by at least 4-fold and improved intercanopy hydraulic conductivity (> than 2-fold) and overall ecohydrologic function. Mechanical treatments retained or increased sagebrush and generally increased the intercanopy herbaceous vegetation. Intercanopy ground surface conditions and soil hydrologic properties in mechanical treatments were generally similar to those in burned areas but were also statistically similar to the same measures in untreated areas in most cases. This suggests that vegetation and ground surface conditions in mechanical treatments are trending toward a significantly improved hydrologic function over time. Treatments had limited impact on soil hydrologic properties within subcanopy areas; however, burning did reduce the soil water repellency strength and the occurrence of strong soil water repellency underneath trees by three- to four-fold. Overall, the treatments over a 13-year period enhanced the vegetation, ground surface conditions, and soil hydrologic properties that promote infiltration and limit runoff generation for intercanopy areas representing ~75% of the area at the sites. However, ecological tradeoffs in treatment alternatives were evident. The variations in woodland responses across sites, treatments, and measurement scales in this long-term study illustrate the complexity in predicting vegetation and hydrologic responses to tree removal on woodland-encroached sagebrush sites and underpin the need and value of multi-scale long-term studies.

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Advancements from Long-Term Research on Woody Plant Encroachment in the Western United States: the Hydrology Component of the Sagebrush Steppe Treatment Evaluation Project (SageSTEP)

10.5194/egusphere-egu2020-12770 ◽

2020 ◽

Author(s):

C. Jason Williams ◽

Frederick B. Pierson ◽

Patrick R. Kormos ◽

Osama Z. Al-Hamdan ◽

Sayjro K. Nouwakpo ◽

...

Keyword(s):

United States ◽

Woody Plant ◽

Western United States ◽

Sagebrush Steppe ◽

Woody Plant Encroachment ◽

Short Term ◽

Modeling Tools ◽

Erosion Processes ◽

Tree Removal

<p>Mitigating and reversing negative ecohydrologic impacts of woody plant encroachment is of global concern. Current knowledge on the ramifications of woody plant encroachment and landscape responses to management is largely based on short-term or point-in-time field studies. The limited longevity of these studies is often dictated by the short-term nature of funding sources and associated infrastructure. Short-term studies advance process-based ecohydrologic knowledge of natural systems and yield valuable insight on treatment effects for various practices to mitigate woody plant encroachment. However, scientists, public and private land owners, and policy makers require knowledge of long-term effectiveness of treatment practices and associated conceptual and quantitative tools to successfully target land management expenditures and actions. This presentation highlights science-based knowledge and ecohydrologic model advancements in management of woody plant encroachment over a nearly 15 yr study period associated with ecohydrologic research at multiple sites in the sagebrush biome within the Great Basin Region of the western United States (the SageSTEP study, www.sagestep.org). The sagebrush biome is considered one of the most ecologically important and imperiled rangeland domains in the United States. A primary driver of degradation to the sagebrush biome is encroachment by pinyon and juniper conifers. These encroaching trees can outcompete sagebrush vegetation for soil and water resources and ultimately propagate and perpetuate pinyon and juniper woodland conditions with extensive bare ground and amplified runoff and soil loss. This study evaluated the ecohydrologic impacts of pinyon and juniper encroachment on sagebrush steppe and the long-term effectiveness of various tree-removal practices to restore sagebrush steppe vegetation and associated ecohydrologic function. Experiments in the study include assessment of vegetation, ground cover, soils, and infiltration, runoff, and erosion processes spanning point to hillslope spatial scales prior to tree removal treatments and at time periods 1 yr, 2 yr, 9 yr, and 13 yr after tree removal. Research products include: 1) advances in conceptual and quantitative understanding of linkages in vegetation and hydrology and erosion processes for the sagebrush steppe ecosystem, 2) enhancements to various conceptual ecological models and the Rangeland Hydrology and Erosion Model (RHEM) tool, 3) advanced understanding of the effectiveness of various tree-removal practices across diverse conditions in the sagebrush biome, and 4) delivery of an extensive publicly-available dataset for developing, enhancing, and/or evaluating other conceptual and quantitative ecohydrologic and erosion models. Lastly, the collective advances in science-based knowledge and modeling tools from the study demonstrate the utility and value of funding and conducting long-term ecohydrological research, particularly for ecologically important biomes around the world. &#160;&#160;</p><p>&#160;</p>

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Long Term Observation of Earth Potetial Difference and its Relationship with Electro-Static Field at Ground Surface (Qualitative Analysis of Micro Variation in Earth Potential Difference)

IEEJ Transactions on Electronics Information and Systems ◽

10.1541/ieejeiss1987.115.4_568 ◽

1995 ◽

Vol 115 (4) ◽

pp. 568-573

Author(s):

Nobunao Takeuchi ◽

Ken'Ichi Narita ◽

Tadatoshi Takahashi ◽

Tokushi Chuubachi ◽

Noriyasu Honma ◽

...

Keyword(s):

Qualitative Analysis ◽

Ground Surface ◽

Static Field ◽

Potential Difference ◽

Long Term Observation ◽

Earth Potential

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Spatial patterns of long-term trends in thunderstorms in India

Natural Hazards ◽

10.1007/s11069-021-04644-6 ◽

2021 ◽

Author(s):

Soma Sen Roy ◽

Shouraseni Sen Roy

Keyword(s):

Spatial Patterns ◽

Long Term Trends

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Performance of Norton Quantum Grinding Wheels

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.686.125 ◽

2016 ◽

Vol 686 ◽

pp. 125-130 ◽

Cited By ~ 1

Author(s):

Miroslav Neslušan ◽

Jitka Baďurová ◽

Anna Mičietová ◽

Maria Čiliková

Keyword(s):

Surface Roughness ◽

Ground Surface ◽

Bearing Steel ◽

Grinding Wheel ◽

Grinding Wheels ◽

Grinding Forces ◽

Removal Rates ◽

Surface Burn ◽

Conventional Grinding

This paper deals with cutting ability of progressive Norton Quantum grinding wheel during grinding roll bearing steel 100Cr6 of hardness 61 HRC. Cutting ability of this wheel is compared with conventional grinding wheel and based on measurement of grinding forces as well as surface roughness. Results of experiments show that Norton Quantum grinding wheels are capable of long term grinding cycles at high removal rates without unacceptable occurrence of grinding chatter and surface burn whereas application of conventional wheel can produce excessive vibration and remarkable temper colouring of ground surface. Moreover, while Norton Quantum grinding wheel gives nearly constant grinding forces and surface roughness within ground length at higher removal rates, conventional grinding wheel (as that reported in this study) does not.

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A system to test the ground surface conditions of construction sites—for safe and efficient work without physical strain

Applied Ergonomics ◽

10.1016/j.apergo.2004.08.004 ◽

2005 ◽

Vol 36 (4) ◽

pp. 441-448 ◽

Cited By ~ 5

Author(s):

Ernst Koningsveld ◽

Maarten van der Grinten ◽

Henk van der Molen ◽

Frank Krause

Keyword(s):

Ground Surface ◽

Construction Sites ◽

Physical Strain ◽

Surface Conditions ◽

Efficient Work

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Diagnosing the subsurface buffer on ground-surface temperature under long-term groundwater pumping: effects of the bottom boundary condition placement

Hydrogeology Journal ◽

10.1007/s10040-020-02287-8 ◽

2021 ◽

Author(s):

Chen Yang ◽

Tingting Zheng ◽

Kun Huang ◽

Zheng Lu ◽

You-Kuan Zhang ◽

...

Keyword(s):

Boundary Condition ◽

Surface Temperature ◽

Ground Surface ◽

Groundwater Pumping ◽

Ground Surface Temperature ◽

Bottom Boundary ◽

Bottom Boundary Condition

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Remote Sensing Data for Calibrated Assessment of Wildfire Emissions in Siberian Forests

Proceedings ◽

10.3390/ecrs-2-05161 ◽

2018 ◽

Vol 2 (7) ◽

pp. 348

Author(s):

Evgenii Ponomarev ◽

Eugene Shvetsov ◽

Kirill Litvintsev ◽

Irina Bezkorovaynaya ◽

Tatiana Ponomareva ◽

...

Keyword(s):

Standard Procedure ◽

Remote Sensing Data ◽

Fire Danger ◽

Variable Intensity ◽

Burned Areas ◽

Radiative Power ◽

Terra Modis ◽

Siberian Forests

This study was carried out for Siberia using Terra/Modis satellite data (2002–2016), data of ground surveys on burned areas of different ages, long-term meteorological information, and numerical simulation results. On the basis of meteorological and wildfire databases, we evaluated the probability (~18%) of an extreme fire danger scenario that was found to occur every 8 ± 3 years in different parts of the region. Next, we used Fire Radiative Power (FRP) measurements to classify the varieties of burning conditions for each wildfire in the database. The classification of the annually burned forest area was obtained in accordance with the assessments of burning intensity ranges categorized by FRP. Depending on the fire danger scenario in Siberia, 47.04 ± 13.6% of the total wildfire areas were classified as low-intensity burning, 42.46 ± 10.50% as medium-intensity fire areas, and 10.50 ± 6.90% as high-intensity. Next, we calculated the amount of combusted biomass and the direct emissions for each wildfire, taking into account the variable intensity of burning within the fire polygons. The total annual emissions were also calculated for Siberia for the last 15 years, from 2002 to 2016. The average estimate of direct carbon emission was 83 ± 21 Tg/year, which is lower than the result (112 ± 25 Tg/year) we obtained using the standard procedure.

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Spatially varying constraints of human-caused fire occurrence in British Columbia, Canada

International Journal of Wildland Fire ◽

10.1071/wf16108 ◽

2017 ◽

Vol 26 (3) ◽

pp. 219 ◽

Cited By ~ 6

Author(s):

Philip E. Camp ◽

Meg A. Krawchuk

Keyword(s):

British Columbia ◽

Spatial Patterns ◽

Fire Management ◽

Fire Occurrence ◽

Explanatory Variables ◽

Human Footprint ◽

Key Factor ◽

Key Drivers ◽

Spatially Varying

Human-caused wildfires are controlled by human and natural influences, and determining their key drivers is critical for understanding spatial patterns of wildfire and implementing effective fire management. We examined an array of explanatory variables that account for spatial controls of human-caused fire occurrence from 1990 to 2013 among six ecosystem zones that vary in human footprint and environmental characteristics in British Columbia, Canada. We found that long-term patterns of human-caused fire in ecosystem zones with a larger human footprint were strongly controlled by biophysical variables explaining conditions conducive to burning, whereas fire occurrence in remote ecosystem zones was controlled by various metrics of human activity. A metric representing the wildland–urban interface was a key factor explaining human-caused fire occurrence regardless of ecosystem zone. Our results contribute to the growing body of research on the varying constraints of spatial patterns of fire occurrence by explicitly examining human-caused fire and the heterogeneity of constraints based on human development.

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