Ali Fares | Prairie View A&M University (original) (raw)

Papers by Ali Fares

Science of The Total Environment, Aug 1, 2022

Texas ranks first in the United States in the variety and frequency of most natural disasters, su... more Texas ranks first in the United States in the variety and frequency of most natural disasters, such as flooding, wildfires, hurricanes, winter storms, and droughts. In February 2021, the winter storm named Uri caused an abnormal decline in the air temperature in the southcentral United States, notably in Texas. Right before Uri, most of Texas was going through a drought spell. Thus, this study analyzed how Uri influenced the drought severity, soil profile moisture content, and vegetation cover (Normalized Difference Vegetation Index, NDVI) across Texas. Data used in this analysis was obtained from the web-based geospatial applications gridMET and Crop-CASMA. The collected datasets include the Palmer Drought Severity Index (PDSI), Snow Water Equivalent (SWE), soil moisture, and NDVI at different spatial resolutions. These datasets were aggregated to the county scale using the zonal statistics analysis. The strength of the correlation between SWE and soil moisture was quantified based on the Pearson correlation coefficient. The percentage change in live vegetation cover due to the impact of the frigid temperature and snow coverage across the state was quantified by analyzing the average weekly NDVI before and after the winter storm. There was a reasonably strong correlation between the SWE contribution of Uri and the increase of the rootzone soil moisture (Pearson's r = 0.42). Similarly, the SWE showed a higher correlation with daily rootzone soil moisture with a Pearson's correlation coefficient of 0.49 on March 1. Furthermore, our results revealed a reduction in the NDVI values to less than 0.60 across Texas during the third week of February. Overall, Texas NDVI values seriously decreased due to Uri. Despite its disruptive effects on the state infrastructures and the economy, Uri snow lessened the drought conditions relatively for a short time.

AGU Fall Meeting Abstracts, Dec 1, 2019

AGUFM, Dec 1, 2006

Abstract Mâkaha valley is located on the leeward side of the Wai&#x27;anae mountains on t... more Abstract Mâkaha valley is located on the leeward side of the Wai&#x27;anae mountains on the island of O&#x27;ahu. Like many Hawaiian watersheds, rainfall in Mâkaha valley varies dramatically over short distances: mean annual rainfall increases from about 500 mm near the coast to over 1,900 mm at Mt. Ka&#x27;ala, an average gradient of 170 mm/km. The objective of the current study was to assess the spatial and temporal variability of rainfall in the upper Mâkaha valley (5.5 km2). The study analyzed rainfall data at 8 locations, including the site ...

Elsevier eBooks, 2021

Abstract This first chapter of the book gives an overview of its content. After a brief introduct... more Abstract This first chapter of the book gives an overview of its content. After a brief introduction, the chapter discusses the three sections' content that makes this book. Section one reports on temperatures and severe convective storms; however, section two of the book comprises two chapters on hydrological responses. These two chapters provide in-depth analyses of the present status and future outlook of the respective topics. The last section of the book deals with mitigation and adaptation measures for climate change. Some of its chapters deal with analyzing the potential impacts of climate change and extreme events on ecosystem responses, lifeline infrastructures, green infrastructure, and sea-level rise. The last two chapters of the book give an overview of governance and climate change policies and extreme events.

Engineering reports, Dec 20, 2020

In this paper, we present the design and implementation of a smart irrigation system using Intern... more In this paper, we present the design and implementation of a smart irrigation system using Internet of Things (IoT) technology, which can be used for automating the irrigation process in agricultural fields. It is expected that this system would create a better opportunity for farmers to irrigate their fields efficiently, as well as eliminating the field's under‐watering, which could stress the plants. The developed system is organized into three parts: sensing side, cloud side, and user side. We used Microsoft Azure IoT Hub as an underlying infrastructure to coordinate the interaction between the three sides. The sensing side uses a Raspberry Pi 3 device, which is a low‐cost, credit‐card sized computer device that is used to monitor in near real‐time soil moisture, air temperature and relative humidity, and other weather parameters of the field of interest. Sensors readings are logged and transmitted to the cloud side. At the cloud side, the received sensing data is used by the irrigation scheduling model to determine when and for how long the water pump should be turned on based on a user‐predefined threshold. The user side is developed as an Android mobile app, which is used to control the operations of the water pump with voice recognition capabilities. Finally, this system was evaluated using various performance metrics, such as latency and scalability.

Pedosphere, Oct 1, 2009

Several newly developed capacitance sensors have simplified real-time determination of soil water... more Several newly developed capacitance sensors have simplified real-time determination of soil water content. Previous work has shown that salinity and temperature can affect these sensors, but relatively little has been done to correct these effects. The objectives of this study were to evaluate the effect of media temperature and salinity on the apparent water content measured with a single capacitance sensor (SCS), and to mitigate this effect using a temperature dependent scaled voltage technique under laboratory conditions. A column ...

AGUFM, Dec 1, 2001

Abstract Citrus root systems are exposed to different thermal and hydrologic conditions as a resu... more Abstract Citrus root systems are exposed to different thermal and hydrologic conditions as a result of tree canopy shading and undertree microirrigation. Because microsprinklers wet only part of the soil surface and are located under the tree, roots under the canopy usually receive more water than those outside the tree canopy. The combined effects of different soil temperature and water input on water redistribution under field conditions have not been fully studied in Florida sandy soils. The objective of this study was to investigate shading ...

AGUFM, Dec 1, 2009

Abstract Hawaii streams are known for generating intense and short-duration runoffs that often ca... more Abstract Hawaii streams are known for generating intense and short-duration runoffs that often cause flash floods. In the past, many of these streams have been reported for decreasing trends in base flow. Trend in precipitation is believed to be correlated with trend in base flow but its relationship with other factors (eg, Groundwater pumping) is unknown. The distributed hydrology soil vegetation model (DHSVM) was applied in the mountainous 13 km2 Makaha watershed, Hawaii to: 1) assess model applicability in predicting ...

51st Annual GSA South-Central Section Meeting - 2017, 2017

Hydrological Processes, Nov 5, 2012

Interception losses in stands of non-native trees in Hawaiian forests and their potential negativ... more Interception losses in stands of non-native trees in Hawaiian forests and their potential negative impacts on fresh water availability are poorly understood. In this study, a canopy water balance analysis was conducted to estimate interception losses using measurements of rainfall (RF), throughfall (TF), and stemflow (SF) at three locations, each dominated by one or more of the following non-native tree species: Psidium cattleianum Sabine (Strawberry guava), Schinus terebinthifolius Raddi (Christmas berry), Syzygium cumini (L.) Skeels (Java plum), and Coffea arabica L. (Coffee). Mean TF expressed as percentage of total RF was the lowest (43.3%) under a monotypic stand of P. cattleianum and the highest (56.5%) under mixture of S. terebinthifolius, P. cattleianum, and S. cumini. Observed SF was highest (33.9%) under P. cattleianum and lowest (3.6%) under a mixture of S. terebinthifolius, P. cattleianum, and S. cumini. The relatively high SF under P. cattleianum can be attributed to its smooth bark, stem density, and steep branching. The mean observed canopy interception varied between 23% under P. cattleianum and 45% at the site dominated by C. arabica. Mean direct TF coefficients from individual events at each location ranged from a low of 0.36 under the canopy dominated by C. arabica to a high of 0.51 under the canopy dominated by S. terebinthifolius, P. cattleianum, and S. cumini. In contrast, the mean SF partitioning coefficients from individual storm events at each location ranged from a low of 0.05 under the canopy dominated by S. terebinthifolius, P. cattleianum, and S. cumini to a high of 0.37 under P. cattleianum. Mean canopy storage capacity was highest (1.90) at the site dominated by S. terebinthifolius, P. cattleianum, and S. cumini whereas trunk storage capacity was highest (0.54) under the P. cattleianum.

Journal of sustainable agriculture, 2012

This study determined carbon dioxide (CO2) emissions from a tropical soil amended with organic co... more This study determined carbon dioxide (CO2) emissions from a tropical soil amended with organic compost (CP), chicken manure (CM), and untreated controls during three growing seasons of sweet corn (Zea mays L.). The organic amendments resulted in significantly greater CO2 emissions compared with control treatments. The time duration after organic amendment applications significantly affected CO2 emissions, especially during the warmer

Journal of The American Water Resources Association, Dec 1, 2006

Effective and efficient water resource management is undoubtedly one of the most important policy... more Effective and efficient water resource management is undoubtedly one of the most important policy issues facing agriculture in Hawaii in the years ahead. Substantial amount of water could be saved through optimizing plant water uptake and minimizing excess water looses below root zones. Capacitance sensors have been successful in monitoring water content at multiple depths and at different locations in near real-time. The objectives of this work are to use real-time data from capacitance sensors to: i) determine field soil physical properties, i.e., soil hydraulic conductivities and soil water holding capacity; ii) determine irrigation scheduling setting points, i.e. full points and refill points. Six capacitance probes were used to monitor the soil water content in real-time (every 10 minutes) across the field. Each probe has four soil moisture sensors that monitor the water content at 10, 20, 30 and 50 cm below the soil surface. Soil hydraulic conductivity at 10 and 40 cm was determined across the field. Rain and irrigation were also monitored during the period of the study. Among the three investigated tomato plant varieties, Toro variety treatment had lowest water content in all investigated soil depths compared with the two other treatments. This variety seems to have higher water uptake than Ruby and Atila F1 varieties.

Soil Science Society of America Journal, May 1, 2007

International Journal of Climatology, Dec 18, 2012

We examined trends in minimum and maximum temperatures in the Oahu during the period of past 39 (... more We examined trends in minimum and maximum temperatures in the Oahu during the period of past 39 (1969-2007) and 25 (1983-2007) years. We found a strong spatial and temporal variability in the temperature trends on Oahu. During the past 39 years, island-wide minimum temperature has increased by 0.17 • C/decade and shows a considerable variability in trends at individual location. There was no detectable trend found in maximum temperature over the same time period. The year 1983 was identified as the change point in the island-wide minimum temperature. During the recent 25 years annual and summer maximum temperature showed a decline while minimum temperature continued to increase. Trend in diurnal temperature range (DTR) shows a decline during the past 39 years with a stronger decreasing trend during the recent 25 years. The trend in DTR for Oahu is much higher compared to the global DTR trend indicating a rapid warming in minimum temperature. Extreme temperature indices show a general warming during the past 39 years. There has been significant increase in tropical and warm nights at the two urban stations. Maximum temperature generally followed the Pacific Decadal Oscillation (PDO) except the period when there is an increase in Hawaii Rainfall Index (HRI). In contrast, minimum temperature showed better agreement with HRI compared to the PDO, at least up until 1999 after which it showed an increase. Despite the relative cooling in PDO during the recent decade an increase in minimum temperature can be attributed to a decline in HRI.

AGUFM, Dec 1, 2011

Abstract Information on partitioning of gross rainfall in non-native trees in Hawaiian forests is... more Abstract Information on partitioning of gross rainfall in non-native trees in Hawaiian forests is limited. In this study, measurements of gross rainfall (PG), throughfall (TF), and stemflow (SF) were made at three locations in the upper Makaha valley watershed to perform canopy water balance and parameterize Gash analytical model. The three selected locations are dominated by Strawberry guava (Psidium cattleianum), Christmas berry (Schinus terebinthifolius), Java plum (Syzygium cumini), and Coffee (Coffea Arabica) trees. Mean ...

UK PubMed Central (UKPMC) is an archive of life sciences journal literature.

H awaiian watersheds are small, steep, and receive high intensity rainfall events of non-uniform ... more H awaiian watersheds are small, steep, and receive high intensity rainfall events of non-uniform distribution. These geographic and weather patterns result in flashy streams of strongly variable water quality even within various stream segments. Total suspended solids (TSS) and total dissolved solids (TDS) were used to investigate the variability in water quality in the upper part of Manoa Stream in Honolulu, Hawaii. With a few interruptions, water samples were taken on a daily basis between September 2005 and June 2006. The samples were analyzed for TSS and TDS, and varied from almost 0 to 724 and to 302 mg L-1 , respectively. During the raining season (October through March) TSS and TDS were more variable, and TSS was higher than in the dry season (April through June). No relation was observed between TSS and TDS and discharge. This may be explained by the heterogeneous rainfall distribution which causes varying contributions from different sources. During one rainfall event TSS and TDS also varied considerably in time. Both TSS and TDS showed increasing trends going downstream suggesting that the urbanized area generates more suspended and dissolved matter than the forested conservation area upstream. However, given the large variability in TSS and TDS, the increasing trend downstream is associated with high uncertainty. The results of this study stress the necessity of recognizing the variability in water quality of small streams for setting up a monitoring strategy, adopting a modeling approach to predict water quality or extrapolating data from limited samples to annual loads in coastal regions.