International Center for Arid and Semi-Arid Land Studies
The International Center for Arid and Semiarid Land Studies (ICASALS) at Texas Tech University was created in 1966 to promote the university's special mission of the interdisciplinary study of arid and semiarid environments and the human relationship to these environments from an international perspective. The purpose of ICASALS is to stimulate, coordinate and implement teaching, research, and public service activities concerning all aspects of the world's arid and semiarid regions, their people and their problems.
The International Center for Arid and Semiarid Land Studies (ICASALS) and the Office of International Affairs announce the start of a new program to host foreign Fulbright Scholars at Texas Tech University campus interested in the study and research of the several aspects involving Arid and Semiarid landscapes.
Each year roughly 850 faculty and professionals from around the world receive Fulbright Scholar grants for advanced research and university lecturing in the United States. Individual grants are available to scholars from over 100 countries. Individuals who meet the eligibility requirements apply for grants through the Fulbright commission/foundation or public affairs section of the U.S. embassy in their home countries. After a thorough selection process in the home country, final approval for awards is issued by the presidentially appointed Fulbright Foreign Scholarship Board (FSB) in the United States. Exchanges range in length from three to twelve months.
Individuals interested in participating of this opportunity at Texas Tech University, please contact Dr. Jorge Salazar-Bravo by email (email@example.com) or call (806.834.3718).
Arid Land Research and Management
This study explores the habitat suitability for an endangered species, Hedysarum criniferum, in Iran using fuzzy logic. The study measured 24 environmental variables including soil, climate, and physiographic variables of eight natural habitats of H. criniferum as the predictive variables and the percent cover of the species as the response variable. The most important environmental factors influencing species distribution and the species response curves were determined by principal component analysis (PCA) and the generalized linear model, respectively. The species habitats were classified by the developed fuzzy model. The results revealed that the seedling length and germination percentage in the site with the fuzzy suitability of 0.6 differed from those in the two other sites with the fuzzy suitability of 0.5 and 0.3 significantly. The method used in this study can be employed in predicting optimal habitats for other endangered species in different ecosystems.
Journal of Arid Land
This study examines hydrothermal condition in Central Asia based on bias-corrected multi-model ensembles (MMEs) from the Coupled Model Intercomparison Project Phase 6 (CMIP6) under four Shared Socioeconomic Pathway and Representative Concentration Pathway (SSP-RCP) scenarios (SSP126 (SSP1-RCP2.6), SSP245 (SSP2-RCP4.5), SSP460 (SSP4-RCP6.0), and SSP585 (SSP5-RCP8.5)) during 2015–2100. The bias correction and spatial disaggregation, water-thermal product index, and sensitivity analysis were used in this study. The results showed that the hydrothermal condition is mismatched in the central and southern deserts, whereas the region of Pamir Mountains and Tianshan Mountains as well as the northern plains of Kazakhstan showed a matched hydrothermal condition. Compared with the historical period, the matched degree of hydrothermal condition improves during 2046–2075, but degenerates during 2015–2044 and 2076–2100. The change of hydrothermal condition is sensitive to precipitation in the northern regions and the maximum temperatures in the southern regions. The result suggests that the optimal scenario in Central Asia is SSP126 scenario, while SSP585 scenario brings further hydrothermal contradictions. This study provides scientific information for the development and sustainable utilization of hydrothermal resources in arid and semi-arid regions under climate change.
The present study uses a combination of global climatic data, soil observations and ecohydrological models to show that average precipitation and seasonality have contrasting impacts on soil salinization. The findings show that aridity enhances salinization by lowering soil moisture and suppressing leaching events. By contrast, rainfall seasonality can reduce salt accumulation in the soil by boosting percolation during the wet season, when salt removal efficiency is greatest. Consequently, salt removal is more effective in regions where seasonality is coupled with strong asynchronicity between water supply and demand, such as in Mediterranean climates. The study concludes that neglecting the interplay of aridity, seasonality and asynchronicity may lead to inaccurate assessments of the impacts of climate on global soil salinization.
The terrestrial carbon sink slows the accumulation of carbon dioxide (CO2) in the atmosphere by absorbing roughly 30% of anthropogenic CO2 emissions, but varies greatly from year to year. The resulting variations in the atmospheric CO2 growth rate (CGR) have been related to tropical temperature and water availability. The apparent sensitivity of CGR to tropical temperature (γTCGR) has changed markedly over the past six decades, however, the drivers of the observation to date remains unidentified. This study uses atmospheric observations, multiple global vegetation models and machine learning products to analyze the cause of the sensitivity change. The results revealed that a threefold increase in γTCGR emerged due to the long-term changes in the magnitude of CGR variability (i.e., indicated by one standard deviation of CGR; STDCGR), which increased 34.7% from 1960-1979 to 1985-2004 and subsequently decreased 14.4% in 1997-2016. The study concludes that outsized influence of extreme droughts over a small fraction of vegetated surface amplified the interannual variability in CGR and explained the observed long-term dynamics of γTCGR.
In arid and semi-arid ecosystems, rainfall and rainfall temporal distribution shape species communities and multi-trophic interactions. This study examines precipitation effects and microhabitat conditions on multi-trophic interactions of ground-dwelling arthropods in an arid savannah. The study measured the effects of seasonal rainfall, plant cover and soil texture on community composition and activity density of arthropods of different trophic levels and investigated the critical window of vegetation and occurrence arthropods in relation to rainfall. The results showed that arthropod community composition was determined by seasonal rainfall and plant cover. Soil texture did not explain arthropod response sufficiently. Especially detritivorous arthropods were strongly affected by precipitation and can therefore serve as indicators of droughts. This highlights the importance of short-term rain pulses for multi-trophic interactions among arthropods and emphasized the relevance of studying detailed precipitation effects for the arthropod diversity and ecosystem stability in arid ecosystems.
- Sufia Akter Neha is going to defend her MS thesis on June 23rd, 2022 at 12.00 PM in Biology Room 106. Her thesis focuses on "Fine-scale spatial variation shape fecal microbiome diversity and composition in black-tailed prairie dogs (Cynomys ludovicianus)".
- Three new students were admitted to Arid Land Studies program: Rafael Freitas (Brazil), Susana Revollo (Bolivia), and Victor Onuoha.