Physical Sciences and Mathematics Commons^™

Investigation On The Temporal Variation Of Vegetation Cover In Karaj River Basin (1973-1993), M. Mohseni Saravi, A. Malekian, B. Mohammadi Golrang

IGC Proceedings (1997-2023)

Area changes in vegetation cover depend on several climatic and edaphic factors as well as direct and indirect human activities. Vegetation maps in a region are mosaics of various associations and types, which clearly show their characteristics and provide a useful tool for classification purposes. Kochler (1967) suggested that vegetative forms and species are 2 most important factors for descriptive purposes. This research aimed mainly to determine the vegetation types based on floristic-physiognomic forms and comparison of vegetation cover maps of 2 different dates to clarify the temporal variations of vegetation cover over this period. This detection of change would …

Rangelands In The Mediterranean Zone Of Croatia, J. Rogosic

IGC Proceedings (1997-2023)

Rangelands dominate the landscape of the Mediterranean part of Croatia along the Adriatic coastline, occupying 83% of the agricultural land (1.7 million ha) and 40% of the entire country. The proportion of rangelands is considerably higher in the Mediterranean littoral than in other ecological regions of Croatia. Sheep and goats are widespread in the region, comprising 76% of total sheep and goat numbers in Croatia. However, in comparison to other regions of Croatia, livestock production in the Mediterranean zone is not well developed. Continuous grazing begun too early in the growing season has caused substantial rangeland degradation and a decline …

Importance Of Vegetation In Tsunami Mitigation: Evidence From Large Eddy Simulations With Fluid-Structure Interactions, Abhishek Mukherjee

Dissertations

Communities worldwide are increasingly interested in nature-based solutions like coastal forests for the mitigation of coastal risks. Still, it remains unclear how much protective benefit vegetation provides, particularly in the limit of highly energetic flows after tsunami impact. The present thesis, using a three-dimensional incompressible computational fluid dynamics model with a fluid-structure interaction approach, aims to quantify how energy reflection and dissipation vary with different degrees of rigidity and vegetation density of a coastal forest.

In this study, tree trunks are represented as cylinders, and the elastic modulus of hardwood trees such as pine or oak is used to characterize …

Post Wildfire Vegetation Response To The Wildland-Urban Interface: A Case Study Of The Station Fire, Angelo C. De Guzman, Raju Bista, Parveen K. Chhetri

CSU Journal of Sustainability and Climate Change

In the past, wildfires served as a method for mother nature to promote biodiversity and to help maintain a functioning ecosystem. However, climate change alters the fire regime, significantly impacting vegetation recovery. Human disturbances and increased land use and land cover heighten vegetation disruption and abundance after a fire. Wildland-urban interface (WUI) – the region where the vegetation intermingles with the roads, houses, and human-made structures – threatens vegetation and the human population. Overall vegetation recovery after the Station Fire of 2009 spread through the San Gabriel Mountains, Los Angeles County was observed using Digital Elevation Model (DEM), Normalized Difference …

Hydrologic Implications Of Snow-Vegetation Interactions In A Semiarid Mountain Climate, Maggi Kraft

Boise State University Theses and Dissertations

Knowledge of the complex interaction between snow, vegetation, and streamflow in semiarid mountain climates is necessary for predicting water resources. The effects of warming temperatures on snow distribution will cascade into vegetation water use and streamflow. Due to our reliance on snow water resources, it is necessary to understand how vegetation affects snow distribution, how vegetation uses snow water inputs and the subsequent effects on streamflow in the current and warming climate. The overall objective of this research is to improve our understanding of snow-vegetation interactions in a semiarid climate. In this dissertation, I use field data to evaluate how …

Characterizing The Vegetation And Effects Of Climate Change On Parris Island, A Sea Island Ecosystem, Cody Hart Goodson

Theses, Dissertations and Capstones

Coastal habitats provide many ecosystem services, protecting coastlines from storm surges and erosion, diminishing the effects of eutrophication, sequestering large amounts of carbon, and acting as vital wildlife habitat. Sea-level rise and increased storm surge intensity associated with climate change are increasingly disrupting coastal habitats. These disturbances can shift environmental gradients that drive the zonation of coastal vegetation types, driving habitat conversion. Monitoring coastal habitat conversion can improve our understanding of the dynamic effects of climate change on these landscapes. Therefore, our objectives for chapter 1 were to identify and describe the distributions of vegetation types present on Marine Corps …

Effects Of Salix Psammophila On Groundwater Recharge In A Semiarid Area Of North China, Lizhu Hou, Jingdong Gao, Bill X. Hu, Xixi Wang

Civil & Environmental Engineering Faculty Publications

Study region: The semiarid Mu Us Sandy Land (MUSL) was selected for this study. It is in the farming-pastoral ecotone of north China and functions as an eco-environmental barrier.

Study focus: Afforestation can mitigate desertification and soil erosion by improving hydrologic condition, which is particularly true for semiarid and arid regions. However, little is known about the quantitative response of hydrologic improvement to afforestation level that can be measured by leaf area index (LAI). The objective was to setup and use a physically-based model to quantitatively assess the dynamics of water fluxes from Salix psammophila afforestation in the MUSL.

New …

Numerical Study Of Sediment Suspension Affected By Rigid Cylinders Under Unidirectional And Combined Wave-Current Flows, Sha Lou, Xiaolan Chen, Shengyu Zhou, Gangfeng Ma, Shuguang Liu, Larisa Dorzhievna Radnaeva, Elena Nikitina, Irina Viktorovna Fedorova

Civil & Environmental Engineering Faculty Publications

Sediment transport modeling for flows with cylinders is very challenging owing to the complicated flow–cylinder–sediment interactions, especially under the combined wave-current flows. In this paper, an improved formulation for incipient sediment suspension considering the effect of cylinder density (i.e., solid volume fraction) is employed to simulate the bottom sediment flux in the flow with cylinders. The proposed model is calibrated and validated using laboratory measurements under unidirectional and combined wave-current flows in previous studies. It is proved that the effects of cylinders on sediment suspension can be accounted for through a modified critical Shields number, and the proposed model is …

Impact Of Riverbank Lupine (Lupinus Rivularis) On Grand Fir (Abies Grandis) Ectomycorrhizal Symbioses, Andrew Labay

WWU Graduate School Collection

Lupine (Lupinus rivularis) is used in the revegetation of coarse sediments surrounding the Elwha basin in Washington State due to its ability to improve soil conditions. Previous research illustrated that seeding lupine with conifers increased growth and foliar nitrogen, however, decreased ectomycorrhizal (ECM) root colonization, an important symbiosis for conifers used in restoration. We hypothesized the observed decrease in ECM may be due to lupine increasing soil nitrogen, negating the need for a fungal symbiont. To investigate this, we explored the interaction between lupine and ECM colonization of grand fir (Abies grandis) in both a field …

Assessment Of Water Quality Index, Light Attenuation, And Nutrient Sequestering By Submerged Aquatic Vegetation In The Detroit River, John Scannell

Electronic Theses and Dissertations

This thesis assessed water quality – submerged aquatic vegetation interactions in the Detroit River. Submerged aquatic vegetation provides essential ecosystem services that support aquatic biodiversity and regulating ecosystem services such as carbon sinks, purifying water and nutrient cycling. Chapter 2 explored how degraded water quality in the Detroit River limits submerged aquatic vegetation via light limitation. A water quality index and light extinction coefficients were measured at 21 sites along with installation of in-situ water quality sondes at 4 sites to measure water quality at high temporal resolution. The river wide median euphotic depth was estimated to be 1.30 m, …