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  1. The rainfall pattern seen in the Indian Cardamom Hills (ICH) has been extremely variable and complicated, with El Niño -Southern Oscillation (ENSO) playing a crucial role in shaping this pattern. In light of this, more investigation is required through improved statistical analysis. During the study period, there was greater variability in rainfall and the frequency of rainy days. About 2,730 mm of rainfall was reported in 2018, while the lowest amount (1168.3 mm) was registered for 2016. The largest decrease in decadal rainfall (>65 mm) was given by the decade 1960–1969, followed by 1980–1989 (>40 mm) and 2010–2019 (>10 mm). In the last 60 years of study, there has been a reduction of rainy days by 5 days in the last decade (2000–2009), but in the following decade (2010–2019), it registered an increasing trend, which is only slightly <2 days. The highest increase in decadal rainy days was observed for the 1970–1979 period. The smallest decadal increase was reported for the last decade (2010–2019). Total sunshine hours were the highest (1527.47) for the lowest rainfall year of 2016, while the lowest value (1,279) was recorded for the highest rainfall year (2021). The rainfall characteristics of ICH are highly influenced by the global ENSO phenomenon, both positively and negatively, depending on the global El Nino and La Nina conditions. Correspondingly, below and above-average rainfall was recorded consecutively for 1963–1973, 2003–2016, and 1970–2002. Higher bright forenoon sun hours occurred only during SWM months, which also reported maximum disease intensity on cardamom. The year 2016 was regarded as a poorly distributed year, with the lowest rainfall and the highest bright afternoon sun hours during the winter and summer months (January-May). Over the last three decades, the production and productivity of cardamom have shown a steady increase along with the ongoing local climatic change. Many of our statistical tests resulted in important information in support of temporal climatic change and variability. Maintaining shade levels is essential to address the adverse effects of increasing surface air temperature coupled with the downward trend of the number of rainy days and elevated soil temperature levels. 
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    Free, publicly-accessible full text available June 13, 2024
  2. Droughts and heatwaves are rising concerns with regard to the frequent formation of the compound or concurrent extremes (CEs), which can cause greater havoc than an individual event of a higher magnitude. Recently, they have been frequently detected to form CEs together or with other events (e.g., floods, aridity, and humidity events) concurrently or with spatiotemporal lags. Therefore, this systematic review assesses these CEs by reviewing the following aspects: CE hotspots, events, and variable combinations that form CEs; frequently analyzed CE parameters (e.g., frequency and severity); large-scale modes of climate variability (CV) as drivers alongside the approaches to relate them to CEs; and CE impacts (e.g., yield loss and fire risk) alongside the impact integration approaches from 166 screened publications. Additionally, three varied analysis frameworks of CEs are summarized to highlight the different analysis components of drought- and heatwave-associated CEs, which is the novelty of this study. The analysis frameworks vary with regard to the three major assessment objectives: only CE parameters (event–event), driver association (event–driver), and impacts (event–impact). According to this review, the most frequently reported hotspots of these CEs in global studies are southern Africa, Australia, South America, and Southeast Asia. In regional studies, several vital hotspots (e.g., Iberian Peninsula, Balkans, and Mediterranean Basin) have been reported, some of which have not been mentioned in global studies because they usually report hotspots as broader regions. In addition, different event combinations (e.g., drought and heatwave; and heatwave and stagnation) are analyzed by varying the combination of variables, namely, temperature, precipitation, and their derived indices. Thus, this study presents three major analysis frameworks and components of drought- and heatwave-associated CE analysis for prospective researchers. 
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  3. The Ogallala Aquifer is one of the most productive agricultural regions and is referred to as the “breadbasket of the world”. It covers approximately 225,000 square miles beneath the Great Plains region spanning the states of Texas, New Mexico, Oklahoma, Kansas, Nebraska, South Dakota, Wyoming, and Colorado. The aquifer is a major water source for the region, with its use exceeding recharge. Previous studies have documented climate changes and their impacts in the region. However, this is the first study to document temperature and precipitation changes over the entire Ogallala region from 35 General Circulation Models participating in Phase 5 of the Climate Model Intercomparison Project (CMIP5). The main study objectives were (1) to provide estimates of present and future climate change scenarios for the High Plains Aquifer, (2) to translate the temperature and precipitation changes to agro-ecosystem indicator changes for Kansas using scenario funnels, and (3) to make recommendations for water resource and ecosystem managers to enable effective planning for the future availability of ecosystem services. The temperature change ranged from −4 °C to 8 °C, while the precipitation changes were between −50% to +50% over the region. This study improves the understanding of climate change on water resources and agro-ecosystems. This knowledge can be used to evaluate similar resources where the replenishment rate is slow. 
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  4. Land use change analysis provides valuable information for landscape monitoring, managing, and prioritizing large area conservation practices. There has been significant interest in the southeastern United States (SEUS) due to substantial land change from various economic activities since the 1940s. This study uses quantitative data from the Economic Research Service (ERS) for landscape change analysis, addressing land change among five major land types for twelve states in the SEUS from 1945 to 2012. The study also conducted a literature review using the PSALSAR framework to identify significant drivers related to land type changes from research articles within the region. The analysis showed how each land type changed over the period for each state in the time period and the percentage change for the primary drivers related to land use change. The literature review identified significant drivers of land use and land cover change (LULCC) within the SEUS. The associated drivers were categorized into natural and artificial drivers, then further subdivided into eight categories related to land type changes in the region. A schematic diagram was developed to show land type changes that impacted environmental changes from various studies in the SEUS. The results concluded that Forest land accounted for 12% change and agricultural land for 20%; population growth in the region is an average of 2.59% annually. It also concluded that the need for research to understand past land use trends, direction and magnitude of land cover changes is essential. Significant drivers such as urban expansion and agriculture are critical to the impending use of land in the region; their impacts are attributed to environmental changes in the region and must be monitored. 
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  5. Habitat suitability (HS) describes the ability of the habitat to support living organisms. There are several approaches to estimate habitat suitability. These approaches are specific to a species or habitat or estimate general HS broadly across multiple species or habitats. The objectives of the study were to compare the approaches for estimating HS and to provide guidelines for choosing an appropriate HS method for conservation. Three HS estimation methods were used. Method 1 scores the suitability based on the naturality of the habitat. Method 2 uses the average of HS values found in the literature. Method 3 uses the species richness as an indicator for HS. The methods were applied to a case study in the Choctawhatchee River Watershed. GIS applications were used to model the suitability of the watershed. The advantages and disadvantages of the HS methods were then summarized. The multiple HS maps created using the three methods display the suitability of the watershed. The highest suitability occurred in the southern parts of the region. Finally, a decision support tool was developed to help determine which approach to select based on the available data and research goals. 
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  6. This manuscript aims to present the framework for the development of a four-stage tool for sustainable groundwater management as one of the highly interactive three-day workshop products. The four stages in the tool are (1) representing the target system, (2) description of the target system using components of DPSIR framework (drivers, pressures, state, impact, responses), (3) development of causal chains/loops, and (4) identifying knowledge gaps and articulating next steps. The tool is an output from the two-day Indo-US bilateral workshop on "Integrated Hydrochemical Modeling for Sustainable Development and Management of Water Supply Aquifers”. Four case studies from the invited talks, panel discussions, and breakout sessions were selected to demonstrate the developed four-stage framework to a coastal aquifer (India) and in high plains in Floridian, Piedmont, and Blueridge aquifers (United States of America). The developed tool can be practically used in the development of strategies for the sustainable use of groundwater in various regions around the world (e.g., planning/building/maintaining groundwater recharging structures). Continued work can result in establishing a center for excellence as well as developing a network project. The recommendations from the workshop were: (1) developing vulnerability analysis models for groundwater managers; (2) treatment and new ways of using low-quality groundwater; (3) adopting groundwater recharge; (4) mitigating pollutants getting into the aquifer; and (5) reducing groundwater use. This study provides a framework for future researchers to study the groundwater table related to the effectiveness of water recharging structures, developing a quantitative model from the framework. Finally, recommendations for a future study are more data collection on groundwater quality/recharge as well as enhancing outreach activities for sustainable groundwater management. 
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  7. Abstract This study evaluated the effects of water stress on rice yield over Punjab and Haryana across North India by integrating Weather Research Forecasting (WRF) and Decision Support System for Agrotechnology Transfer (DSSAT) models. Indian Remote Sensing Satellite datasets were used to define land use/land cover in WRF. The accuracy of simulated rainfall and temperature over Punjab and Haryana was evaluated against Tropical Rainfall Measuring Mission and automated weather station data of Indian Space Research Organization, respectively. Data from WRF was used as weather input to DSSAT to simulate rice yield in Punjab and Haryana for 2009 and 2014. After simulated yield has been evaluated against district-level observed yield, the water balance components within the DSSAT model were used to analyze the impact of water stress on rice yield. The correlation (R 2 ) between the crop water stress factor and the rice yield anomaly at the vegetative and reproductive stage was 0.64 and 0.52 for Haryana and 0.73 and 0.68 for Punjab, respectively. Severe water stress during the flowering to maturity stage inflicted devastating effects on yield. The study concludes that the regional climate simulations can be potentially used for early water stress prediction and its impact on rice yield. 
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  8. Fertilizers and pesticides have been widely used in agriculture production, causing polluted soil, water, and atmosphere. This study aims to quantify air emissions from pesticides and fertilizers applied for peanut production in Georgia during selected years (1991, 1999, 2004, 2013, and 2018). Specifically, the oral and dermal potential impacts from pesticide emissions and the global warming potential (GWP) impact from fertilizers to air were investigated. This study followed the ISO 14040 series standards for life cycle assessment (LCA) methodology to assess six active ingredients (AIs) (2,4-DB, Bentazon, Chlorothalonil, Ethalfluralin, Paraquat, and Pendimethalin) and one greenhouse gas (nitrous oxide N2O). Their physical and chemical characteristics and the temporal scales greatly influenced the oral and dermal toxicity impacts. According to the low values obtained for Henry’s law (KH) and vapor pressure (VP), 2,4-dichlorophenoxy butanoic (DB), Pendimethalin, and Chlorothalonil have a higher impact on the continental air scale. The effect factor (EF) from oral exposure was higher in 2,4-DB, Bentazon, and Pendimethalin than dermal exposure, according to the relatively low lethal dose (LD50) for oral exposure, while the EF of Ethalfluralin and Chlorothalonil was the same for oral and dermal exposure according to their similar LD50. 
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  9. Intensive cardamom cultivation in Indian Cardamom hills (ICH) has been related to severe ecological and environmental implications that can challenge the long-term sustainability of cardamom. This research study and analysis proposes a novel system approach for sustainable agroecological production of cardamom in southern India. The effects of intensive cardamom cultivation on its forest environment had been significant. A considerable increase in surface air temperature was observed in the ICH during the last three decades (1990–2020). The climate of the Cardamom hill reserves (CHR) has a very high variability of daily cycles (surface air temperature and relative humidity) compared to low variability of yearly cycles, which helped minor and major pests and diseases occur and spread throughout the season. The current hydrothermal condition of the soil fostered the occurrence of soil insect pests, resulting in higher pesticide use. Epiphytes peculiar to the CHR forest have been eliminated due to repeated, intense shade lopping of each tree. Variability occurred in cardamom growth and development and yield can be attributed to changes in the microclimatic environment prevailing in the micro habitats of the sloping hillsides. This study has revealed the possible link and various dimensions between the intensive growing practices that were positively reflected in its local climate and production system. The 75% shade level under the cardamom canopy influences the cardamom microclimatic conditions, the relative humidity close proximity with panicles was maximum (88.9%), and the mean air temperature was minimum (18.4°C). On the contrary, the relative humidity at canopy top was reduced (78.7%) but the mean air temperature was still high (27.4°C). This study also suggests that future energy transfers in the CHR production system must be understood for improving the long-term agricultural sustainability of cardamom cultivation in the ICH. 
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  10. The recent decade has witnessed an increase in irrigated acreage in the southeast United States due to the shift in cropping patterns, climatic conditions, and water availability. Peanut, a major legume crop cultivated in Georgia, Southeast United States, has been a staple food in the American household. Regardless of its significant contribution to the global production of peanuts (fourth largest), studies related to local or regional scale water consumption in peanut production and its significant environmental impacts are scarce. Therefore, the present research contributes to the water footprint of peanut crops in eight counties of Georgia and its potential ecological impacts. The impact categories relative to water consumption (water depletion—green and blue water scarcity) and pesticide use (water degradation—potential freshwater ecotoxicity) using crop-specific characterization factors are estimated for the period 2007 to 2017 at the mid-point level. These impacts are transformed into damages to the area of protection in terms of ecosystem quality at the end-point level. This is the first county-wise quantification of the water footprint and its impact assessment using ISO 14046 framework in the southeast United States. The results suggest inter-county differences in water consumption of crops with higher blue water requirements than green and grey water. According to the water footprint analysis of the peanut crop conducted in this study, additional irrigation is recommended in eight Georgia counties. The mid-point level impact assessment owing to water consumption and pesticide application reveals that the potential freshwater ecotoxicity impacts at the planting and growing stages are higher for chemicals with high characterization factors regardless of lower pesticide application rates. Multiple regression analysis indicates blue water, yield, precipitation, maximum surface temperature, and growing degree days are the potential factors influencing freshwater ecotoxicity impacts. Accordingly, a possible impact pathway of freshwater ecotoxicity connecting the inventory flows and the ecosystem quality is defined. This analysis is helpful in the comparative environmental impact assessments for other major crops in Georgia and aids in water resource management decisions. The results from the study could be of great relevance to the southeast United States, as well as other regions with similar climatic zones and land use patterns. The assessment of water use impacts relative to resource availability can assist farmers in determining the timing and layout of crop planting. 
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