IU Indianapolis ScholarWorks :: Browsing by Author "Jacinthe, Pierre-André"

Browsing by Author "Jacinthe, Pierre-André"

Now showing 1 - 10 of 28

Applications of geospatial analysis techniques for public health
(2016-05-02) Stanforth, Austin Curran; Filippelli, Gabriel; Johnson, Daniel P.; Wang, Lixin; Wilson, Jeffrey; Moreno-Madriñán, Max J.; Jacinthe, Pierre-André
Geospatial analysis is a generic term describing several technologies or methods of computational analysis using the Earth as a living laboratory. These methods can be implemented to assess risk and study preventative mitigation practices for Public Health. Through the incorporation Geographic Information Science and Remote Sensing tools, data collection can be conducted at a larger scale, more frequent, and less expensive that traditional in situ methods. These techniques can be extrapolated to be used to study a variety of topics. Application of these tools and techniques were demonstrated through Public Health research. Although it is understand resolution, or scale, of a research project can impact a study’s results; further research is needed to understand the extent of the result’s bias. Extreme heat vulnerability analysis was studied to validate previously identified socioeconomic and environmental variables influential for mitigation studies, and how the variability of resolution impacts the results of the methodology. Heat was also investigated for the implication of spatial and temporal resolution, or aggregation, influence on results. Methods studying the physical and socioeconomic environments of Dengue Fever outbreaks were also studied to identify patters of vector emergence.
Can ridge-furrow plastic mulching replace irrigation in dryland wheat and maize cropping systems?
(Elsevier, 2017-08) Daryanto, Stefani; Wang, Lixin; Jacinthe, Pierre-André; Earth Science, School of Science
Dryland crop production requires significant water investments, but problems associated with irrigation have been observed in many dryland regions (e.g., China, Australia and the Mediterranean basin). A key strategy for maintaining crop yields without over-exploiting the scarce water resource is by increasing water use efficiency (WUE). Plastic mulching technology for wheat and maize has been commonly used in China, but their effect on yield, soil water content, evapotranspiration (ET), and WUE has not been compared with traditional irrigation. Using a meta-analysis approach, we quantitatively examined the efficacy of plastic mulching in comparison with traditional irrigation in the same region. By covering the ridges with plastic and channeling rainwater into a very narrow planting zone (furrow), our results showed that plastic mulching resulted in a yield increase comparable to irrigated crops but used 24% less water in comparison with irrigation due primarily to a much greater WUE and better retention of soil water. The higher WUE in plastic-mulched croplands was likely a result of a greater proportion of available water being used for transpiration (T) than evaporation (E). Currently production costs and residual plastic pollution hinder worldwide adoption of the technique, despite being a promising strategy for dryland cropping systems.
Characterization of CDOM in saline and freshwater lakes across China using spectroscopic analysis
(Elsevier, 2019-03) Song, Kaishan; Shang, Yingxin; Wen, Zhidan; Jacinthe, Pierre-André; Liu, Ge; Lyu, Lili; Fang, Chong; Earth Sciences, School of Science
Colored dissolved organic matter (CDOM) is a major component of DOM in waters, and plays a vital role in carbon cycling in inland waters. In this study, the light absorption and three-dimensional excitation-emission matrix spectra (EEMs) of CDOM of 936 water samples collected in 2014–2017 from 234 lakes in five regions across China were examined to determine relationships between lake water sources (fresh versus saline) and their fluorescence/absorption characteristics. Results indicated significant differences regarding DOC concentration and aCDOM(254) between freshwater (6.68 mg C L−1, 19.55 m-1) and saline lakes (27.4 mg C L−1, 41.17 m-1). While humic-like (F5) and fulvic-like (F3) compounds contributed to CDOM fluorescence in all lake waters significantly, their contribution to total fluorescence intensity (FT) differed between saline and freshwater lakes. Significant negative relationships were also observed between lake altitude with either F5 (R2 = 0.63, N = 306) or FT (R2 = 0.64, N = 306), suggesting that the abundance of humic-like materials in CDOM tends to decrease with increased in lakes altitude. In high-altitude lakes, strong solar irradiance and UV exposure may have induced photo-oxidation reactions resulting in decreased abundance of humic-like substances and the formation of low molecular weight compounds. These findings have important implications regarding our understanding of C dynamics in lacustrine systems and the contribution of these ecosystems to the global C cycle.
Common Era Midcontinental Hydroclimate Variability Inferred from Iowan Lake Sediments, USA
(2024-02) Goswami, Anusuya; Bird, Broxton; Filippelli, Gabriel; Jacinthe, Pierre-André
Global climate change manifests diverse consequences across the United States, creating distinct challenges in different regions. For example: The Western United States grapples with a notable surge in wildfires and drought events, indicating reduced effective moisture. In contrast, the Eastern part faces severe and frequent flooding events, reflecting higher effective moisture conditions and suggesting an East-West dipole-like climatic pattern. While the current East-West dividing hinge-line sits at 96°W, questions linger about its persistence throughout the late Holocene or whether it has undergone changes over time. Understanding the evolution and stability of this hinge-line is crucial for predicting the impacts of ongoing global warming on various U.S. regions. To address this issue, it is essential to develop additional paleoclimate records from the U.S. Midcontinent, especially those in close proximity to the modern hydroclimate hinge-line. This research focuses on understanding the common era (CE; last 2000 years) hydroclimate variability and its driving mechanisms using lake sediment archives from two hydrologically restricted Iowan kettle lakes, West Lake Okoboji (~1800 years long) and Clear Lake (~2000 years long). The results of multiproxy sedimentological, geochemical, and isotopic analyses reveal a wetter period during the Medieval Climate Anomaly (MCA; 950-1250 CE) and a drier phase during the Little Ice Age (LIA; 1350-1850 CE), aligning with regional patterns in the upper Midwest. Comparisons with regional paleoclimate records suggest that pluvial conditions during the MCA were linked to mean state atmospheric circulation conditions resembling the negative phase of the Pacific-North American (-PNA) teleconnection pattern when Pacific Ocean-atmosphere conditions similarly resembled the negative phase of the Pacific Decadal Oscillation (-PDO). Conversely, drier conditions during the LIA occurred when +PNA-like atmospheric circulation patterns predominated under +PDO-like conditions in the North Pacific Ocean. Comparison with records near the modern hydroclimate hinge-line indicates in-phase relationships with records east of 96˚ W and anti-phased relationships with records west of 96˚ W. This supports idea of the stable hinge line position during the Common Era.
The Contributions of Soil Moisture and Groundwater to Non-Rainfall Water Formation in the Namib Desert
(2019-08) Adhikari, Bishwodeep; Wang, Lixin; Li, Lin; Jacinthe, Pierre-André
Non-rainfall waters such as fog and dew are considered as important source of water in drylands, and the knowledge of possible sources of its formation is very important to make future predictions. Prior studies have suggested the presence of radiation fog in drylands; however, its formation mechanism still remains unclear. There have been earlier studies on the effects of fog on soil moisture dynamics and groundwater recharge. On the contrary, no research has yet been conducted to understand the contribution of soil moisture and groundwater to fog formation. This study, therefore, for the first time intends to examine such possibility in a fog-dominated dryland ecosystem, the Namib Desert. The study was conducted at three sites representing two different land forms (sand dunes and gravel plains) in the Namib Desert. This thesis is divided into two parts: the first part examines evidences of fog formation through water vapor movement using field observations, and the second part simulates water vapor transport using HYDRUS-1D model. In the first part of the study, soil moisture, soil temperature and air temperature data were analyzed, and the relationships between these variables were taken as one of the key indicators for the linkage between soil water and fog formation. The analysis showed that increase in soil moisture generally corresponds to similar increase in air or soil temperature near the soil surface, which implied that variation in soil moisture might be the result of water vapor movement (evaporated soil moisture or groundwater) from lower depths to the soil surface. In the second part of the study, surface fluxes of water vapor were simulated using the HYDRUS-1D model to explore whether the available surface flux was sufficient to support fog formation. The actual surface flux and cumulative evaporation obtained from the model showed positive surface fluxes of water vapor. Based on the field observations and the HYDRUS-1D model results, it can be concluded that water vapor from soil layers and groundwater is transported through the vadose zone to the surface and this water vapor likely contributes to the formation of non-rainfall waters in fog-dominated drylands, like the Namib Desert.
Dissolved carbon and CDOM in lake ice and underlying waters along a salinity gradient in shallow lakes of Northeast China
(Elsevier, 2019) Song, Kaishan; Wen, Zhidan; Jacinthe, Pierre-André; Zhao, Ying; Du, Jia; Earth Sciences, School of Science
The variations of DOC and DIC concentrations in lake ice and underlying waters were examined in 40 shallow lakes across the Songnen Plain, Northeast China. The lakes, frozen annually during winter, included freshwater and brackish systems (EC > 1000 μS cm−1; range: 171–12607 μS cm−1 in underlying water). Results showed that lake ice contained lower DOC (7.2 mg L−1) and DIC (6.7 mg L−1) concentration compared to the underlying waters (58.2 and 142.4 mg L−1, respectively). Large differences in DOC and DIC concentrations of underlying waters were also observed between freshwater (mean ± SD: 22.3 ± 11.5 mg L−1, 50.7 ± 20.6 mg L−1) and brackish lakes (83.3 ± 138.0 mg L−1, 247.0 ± 410.5 mg L−1). A mass balance model was developed to describe the relative distribution of solutes and chemical attributes between ice and the underlying waters. Results showed that water depth and ice thickness were the key factors regulating the spatial distribution of solutes in the frozen lakes. Chromophoric dissolved organic matter (CDOM) absorption coefficient at 320 nm, aCDOM(320) and specific UV absorbance (SUVA254) were used to characterize CDOM composition and quality. Compared to the underlying waters, CDOM present in ice largely included low aromaticity organic substances, an outcome perhaps facilitated by ice formation and photo-degradation. In ice and underlying freshwaters, CDOM predominantly included organic C fractions of high aromaticity, while low aromaticity organic substances were observed for brackish lakes. Results of this study suggest that, if water salinity increases due to climate change and anthropogenic activities, significant changes can occur in the dissolved carbon and fate of CDOM in these shallow lakes.
Drought effects on root and tuber production: A meta-analysis
(Elsevier, 2016-10) Daryanto, Stefani; Wang, Lixin; Jacinthe, Pierre-André; Department of Earth Sciences, School of Science
Roots and tubers such as potatoes and cassava rank within the top six among the world’s most important food crops, yet the extent to which their global production has been adversely affected by drought remains unclear. Greater uncertainties exist on how drought effects co-vary with: (1) root and tuber species, (2) soil texture, (3) agro-ecological region, and 4) drought timing. It is often assumed that potato is drought-sensitive whereas cassava and sweet potato are resistant to drought, but this assumption has not been quantitatively tested. To address these uncertainties, we collected literature data between 1980 and 2015 that reported monoculture root and tuber yield responses to drought under field conditions, and analyzed this large data set using meta-analysis technique. Our results showed that the amount of water reduction was positively related with yield reduction, but the extent of the impact varied with root or tuber species and the phenological phase during which drought occurred. In contrast to common assumptions regarding drought resistance of certain root and tuber crops, we found that yield reduction was similar between potato and species thought to be drought-resistant such as cassava and sweet potato. Here we suggest that drought-resistance in cassava and sweet potato could be more related to survival rather than yield. All root or tuber crops, however, experienced greater yield reduction when drought struck during the tuberization period compared to during their vegetative phase. The effect of soil texture on yield reduction was less obvious, and similarly we did not find any significant effects of region (and related climatic factors) on either yield reduction or drought sensitivity. Our study provides useful information that can inform agricultural planning, and influence the direction of research for improving the productivity and resilience of these under-utilized crops in the drought-prone regions of the world.
Global synthesis of cover crop impacts on main crop yield
(Elsevier, 2024-04-15) Peng, Yu; Wang, Lixin; Jacinthe, Pierre-André; Ren, Wei; Earth and Environmental Sciences, School of Science
Incorporating cover crops into farming systems represents a potential pathway to maintaining crop productivity and achieving multiple environmental benefits. However, how cover crops impact the succeeding crop yield remained a matter of debate. Therefore, this study aims to provide a comprehensive and global scale assessment of cover crop impacts on yield. We conducted a literature synthesis of cover crop studies (104 articles) to collect field-based yield data (1027 records) and used meta-analysis to quantify the impact of cover crops on subsequent main crop yields. Our results showed that cover cropping led to an overall moderate increase in main crop yield, amounting to 2.6%. Specifically, the utilization of leguminous cover crops, cultivation in coarse soil texture and dryland areas, and the implementation of longer cover cropping durations were found to be conducive scenarios to enhance crop yields. Conversely, the use of non-legume cover crops, introducing them to fields under a short-term no-till, especially in fine-textured soils, were impaired to yields. Leguminous cover crops showed the greatest potential for increasing yield (9.8%) particularly when paired with corn. Adopting leguminous cover crops without fertilizing main crops resulted in a 21.8% yield increase. Utilizing cover crops did not affect yield if the field had already under no-till practice. Introducing cover crops on coarser soils and in rainfed drylands can increase yield by 14.1% and 11.4%, respectively. In fine-textured soils, cover crop plus conventional tillage achieved 4.8% yield increase while cover crops plus no-tillage led to a 9.5% yield decrease instead. Consequently, our findings suggested the general yield profitability of cover crops, but substantial variations remain, which was primarily affected by availability of nitrogen and soil moisture. It is advisable to maximize the nitrogen-fixing capability of leguminous cover crops as a nitrogen source for main crops, replacing fertilizer. Particular attention should be paid, and additional management practices should be adopted when using cover crops plus no-tillage in fine-textured soils to avoid yield penalties. These specific supportive measures are suggested to shorten the lag period of yield increase within the initial 1–3 years of cover cropping implementation. Our synthesis quantified the overall cover crop impacts on yield, showcasing variable yield returns across different scenarios. This holistic understanding and comprehensive information can serve to advance the appropriate and targeted adoption of cover crops by policymakers, extension services, and farmers.
Global synthesis of drought effects on cereal production
(Office of the Vice Chancellor for Research, 2016-04-08) Daryanto, Stefani; Wang, Lixin; Jacinthe, Pierre-André
Abstract Drought has been a major cause of agricultural disaster, yet how various factors (e.g., crop species, phenological phases) affect the vulnerability of cereal agriculture to drought remains unclear. Using a data synthesis approach, this study aims to better characterize the effects of these factors and to provide critical information on minimizing yield loss. We collected data from peer-reviewed publications between 1980 and 2015 which examined cereal yield responses to drought using field experiments. We performed unweighted analysis using the log response ratio to calculate the bootstrapped confidence limits of yield responses and calculated drought sensitivities for several key factors. Our results showed that yield reduction varied with species, with wheat having lower sensitivity to drought and yield reduction (20.6%) compared to maize (39.3%) at approximately 60% water reduction. Drought that occurred during the reproductive phase caused greater yield reduction (30%) than when it occurred during the vegetative phase (20%). While cereal cultivation in the drylands was more prone to yield loss than in the non-dryland regions, no difference was observed among sites of different soil texture. Informed by these results, we discuss possible causes and low-cost strategies that may minimize drought effect on crop yield.
Global synthesis of drought effects on cereal, legume, tuber and root crops production: A review
(Elsevier, 2017-01) Daryanto, Stefani; Wang, Lixin; Jacinthe, Pierre-André; Department of Earth Sciences, School of Science
As a result of climate change, drought is predicted to pose greater pressure on food production system than in the past. At the same time, crop yield co-varies with both environmental (e.g., water, temperature, aridity) and agronomic variables (i.e., crop species, soil texture, phenological phase). To improve our quantitative understanding on the effects of these co-varying factors on agricultural productivity, we synthesized previous meta-analysis studies summarizing the results of numerous independent field experiments on drought and its effect on the production of cereal, legume, root and/or tuber (root/tuber) crops. We also included new crops species that were not covered in previous meta-analyses and the effects of heat stress. Our results indicated that cereals tended to be more drought resistant than legumes and root/tubers. Most crops were more sensitive to drought during their reproductive (i.e., grains filling, tuber initiation) than during their vegetative phase, except for wheat, which was also sensitive during vegetative phase. Recovery from drought impact at reproductive phase was either: (i) unfeasible for crops experiencing damage to their reproductive organs (e.g., maize, rice) or (ii) limited for root/tuber crops, provided that water was abundant during the subsequent root/tuber bulking period. Across soil texture, the variability of yield reduction for cereals was also lower in comparison to legume or root/tuber crops, probably due to the extensive and deep rooting system of cereal crops. As crop species, plant phenology, and soil texture were important co-varying factors in determining drought-induced crop yield reduction, no single approach would be sufficient to improve crop performance during drought. Consequently, a combination of approaches, particularly site-specific management practices that consider soil conditions (i.e., intercropping, mulching, and crop rotation) and selection of crop varieties adjusted to the local climate should be adopted in order to improve the sustainability of agricultural production in a changing climate.

Browsing by Author "Jacinthe, Pierre-André"

Results Per Page

Sort Options