Drought Vulnerability Indices in Mexico

Enhancing drought stress tolerance and growth promotion in chiltepin pepper (Capsicum annuum var. glabriusculum) through native Bacillus spp

The drought can cause a decrease in food production and loss of biodiversity. In northern Mexico, an arid region, the chiltepin grows as a semi-domesticated crop that has been affected in its productivity and yield. An alternative to mitigate the effect of drought and aid in its conservation could be using Plant Growth-Promoting Bacteria (PGPB). The present study evaluated the capacity of native Bacillus spp., isolated from arid soils, as PGPBs and drought stress tolerance inducers in chiltepin under controlled conditions. Chiltepin seeds and seedlings were inoculated with native strains of Bacillus spp. isolated from arid soils, evaluating germination, vegetative, and drought stress tolerance parameters. The PGPBs improved vegetative parameters such as height, stem diameter, root length, and slenderness index in vitro. B. cereus (Bc25-7) improved in vitro survival of stressed seedlings by 68% at -1.02 MPa. Under greenhouse conditions, seedlings treated with PGPBs exhibited increases in root length (9.6%), stem diameter (13.68%), leaf fresh weight (69.87%), and chlorophyll content (38.15%). Bc25-7 alleviated severe water stress symptoms (7 days of water retention stress), and isolates B. thuringiensis (Bt24-4) and B. cereus (Bc25-7, and Bc30-2) increased Relative Water Content (RWC) by 51%. Additionally, the treated seeds showed improved germination parameters with a 46.42% increase in Germination Rate (GR). These findings suggest that using PGPBs could be an alternative to mitigate the effect of drought on chiltepin.

In Vitro Embryos of Romosinuano and Tropical Milking Cattle during Three Seasons in Veracruz, Mexico

One of the main factors that influences the fertility of cattle in grazing systems in hot tropical climates is heat stress. The objective of this study was to evaluate the effect of season, breed, hormonal and physiological condition on the quantity and quality of cumulus-oocyte complexes (COCs) and embryos produced in vitro, from Romosinuano (RM) and Tropical Milking (TM) donors. Three ovum pick-up and in vitro fertilization (OPU-IVF) were performed, one per season: hot dry (HD; 10, 10), hot humid (HH; 9, 9) and fresh dry (FD; 7, 10) in RM and LT donors. Serum levels of cortisol, insulin and glucose were measured, in addition to heart rate (HR), respiratory rate (RR) and rectal temperature (RT). Effect of season x genotype interaction (p ≤ 0.05) was observed in all COC variables and only in cleavage embryos (CLI) (p ≤ 0.05). Body weight (BW) affected all COC variables (p ≤ 0.01), except unviable (UNV) although affected degenerated embryos (DEG) (p ≤ 0.01) and total blastocysts (BLAST) (p ≤ 0.01). Cow age only affected viable COCs (VIAB) (p ≤ 0.05), code one blastocysts (BC1) and BLAST (p ≤ 0.01). Cortisol affected total COCs (COCsT), VIAB and total matured in vitro (TMIV) (p ≤ 0.01), as well as CLI, BC1 (p ≤ 0.01) and BLAST (p ≤ 0.05). Insulin affected COCsT (p ≤ 0.01), UNV (p ≤ 0.05), denuded oocytes (DE) (p ≤ 0.01), BC1 and code two blastocysts (BC2) (p ≤ 0.01). Glucose affected all COC variables (p ≤ 0.01), except UNV and all embryo variables except BC2. HR affected COCsT, DE, TMIV (p ≤ 0.01), CLI, BLAST and DEG (p ≤ 0.05). RR affected COCsT, UNV, VIAB, CLI (p ≤ 0.05), BC1, BLAST and DEG (p ≤ 0.01). RT only affected DE, VIAB (p ≤ 0.01) and BLAST (p ≤ 0.05). The seasonal climatic year variation of Veracruz and changes in physiological and hormonal variables have diverse effects on the cumulus-oocyte complexes and embryos produced by RM and TM donors.

Assessment of multidimensional drought vulnerability using exposure, sensitivity, and adaptive capacity components

This study provides a method for analyzing the drought-vulnerability index (DVI) from a multidimensional perspective that includes biophysical and social aspects, considering the Intergovernmental Panel on Climate Change's (IPCC) assessment. The proposed method generates the "exposure index (EI)", "sensitivity index (SI)", and "adaptive capacity index (ACI)" components of the proposed DVI using nine sub-indicators and 29 proxy variables. By using it throughout all of Turkey's provinces, the performance of the developed index was evaluated. In this study, the decision matrices were built utilizing expert knowledge, and the weights of the indicators and variables were obtained by using the Analytical Hierarchy Process (AHP) technique. Moreover, the values of these four indices were classified as "very high, high, moderate, low, and very low," and their geographical distribution across the country was drawn, as well as relevant patterns retrieved. The study's major results show that 17 of the 81 provinces are classified as "very high," 16 as "high," 15 as "moderate," 17 as "low," and the remaining 16 as "very low" drought vulnerable. Another significant result is that the majority of people in the country's south, center, and southeast rely on agriculture and are thus more vulnerable to drought due to socioeconomic underdevelopment in those regions.

The Identification and Classification of Arid Zones through Multicriteria Evaluation and Geographic Information Systems—Case Study: Arid Regions of Northwest Mexico

Arid and semiarid regions are geographic units that cover approximately 43% of the earth’s surface worldwide, and conditions of extreme drought and reduced vegetation cover predominate in these regions. In Mexico, arid and semiarid ecosystems cover more than half of the territory, with desertification, mainly caused by anthropogenic activities and climatic events, as the main problem in these regions. The present research aimed to assess, identify, and classify arid and semiarid zones by employing a methodology based on multicriteria evaluation analysis (MCA) using the weighted linear combination (WLC) technique and geographic information systems (GIS) in the hydrological administrative regions (HARs) of the North Pacific, Northwest, and Baja California Peninsula, located in Northwest Mexico. Data related to aridity, desertification, degradation, and drought were investigated, and the main factors involved in the aridity process, such as surface temperature, soil humidity, precipitation, slopes, orientations, the normalized difference vegetation index (NDVI), and evapotranspiration, were obtained. For the standardization of factors, a fuzzy inference system was used. The weight of each factor was then determined with the analytical hierarchy process (AHP). To delimit arid regions, the classification of arid zones proposed by the United Nations Environment Program (UNEP) was used, and the result was an aridity suitability map. To validate the results, the sensitivity analysis method was applied. Quantitative and geospatial aridity indicators were obtained at the administrative hydrological level and by state. The main results indicated that semiarid and dry subhumid zones predominated, representing 40% and 43% of the surface of the study area, respectively, while arid regions represented 17%, and humid regions represented less than 1%. In addition, of the states for which 100% of the surface lay in the study area, it was observed that Baja California and Baja California Sur had the largest arid and semiarid zones, while subhumid regions predominated in Sonora and Sinaloa.

Agricultural Drought Risk Assessment: A Spatial Analysis of Hazard, Exposure, and Vulnerability in Zacatecas, Mexico

Drought is one of the major threats to water and food security in many regions around the world. The present study focuses on the evaluation of agricultural drought risk from an integrated perspective, that is, emphasizing the combined role of hazard, exposure, and vulnerability to drought. For this purpose, we used the Mexican state of Zacatecas as a case study. This state is one of the most vulnerable to the adverse effects of agricultural drought in the country. The proposed method includes three stages: first, we analyzed the risk of agricultural drought at the municipal scale using the FAO Agricultural Stress Index System (ASIS) in its country version (Country-Level ASIS) and also determined a Drought Hazard Index (DHI). Subsequently, we conducted a municipal assessment of exposure and vulnerability to drought based on a set of socioeconomic and environmental indicators, which we combined using an analytical procedure to generate the Drought Exposure Index (DEI) and the Drought Vulnerability Index (DVI). Finally, we determined a Drought Risk Index (DRI) based on a weighted addition of the hazard, exposure, and vulnerability indices. Results showed that 32% of the state’s municipalities are at high and very high risk of agricultural drought; these municipalities are located mainly in the center and north of the state, where 75.8% of agriculture is rainfed, 63.6% of production units are located, and 67.4% of the state’s population depends on agricultural activity. These results are in general agreement with those obtained by other studies analyzing drought in the state of Zacatecas using different meteorological drought indices, and the results are also largely in line with official data on agricultural surfaces affected by drought in this state. The generated maps can help stakeholders and public policymakers to guide investments and actions aimed at reducing vulnerability to and risk of agricultural drought. The method described can also be applied to other Mexican states or adapted for use in other states or countries around the world.

Socio-economic and environmental vulnerability to heat-related phenomena in Bucharest metropolitan area

In the recent years, the effects of extreme climate phenomena (mainly heat-related) on agricultural crops, infrastructure and human health have become increasingly severe as a result of their complex interactions with the particularities of the urban/rural habitat, as well as the social and economic factors. In Romania, heat-related phenomena (e.g. drought, heat waves) are affecting wide areas in the southern half of the territory where the study area (Bucharest Metropolitan Area) lies. The paper aims to develop a multi-criteria vulnerability assessment using both quantitative and qualitative methods. 23 indicators were selected and processed in order to assess various components of socio-economic and environmental vulnerability to heat-related phenomena using the statistical data available at local administrative units (LAU). The indicators were grouped into the three key components of vulnerability (potential exposure, sensitivity and adaptive capacity) on two dimensions (socio-economic and environmental) resulting two indexes: Socio-Economic Vulnerability Index (SEVI) and Environmental Vulnerability Index (EVI). Finally, an integrated Heat Vulnerability Index (HVI) (using Hull score, average 50 and standard deviation 14) was computed.

Drought Vulnerability in the United States: An Integrated Assessment

Droughts are among the costliest natural hazards in the U.S. and globally. The severity of the hazard is closely related to a region’s ability to cope and recover from the event, an ability that depends on the region’s sensitivity and adaptive capacity. Here, the vulnerability to drought of each state within the contiguous U.S. is assessed as a function of exposure, sensitivity, and adaptive capacity, using socio-economic, climatic, and environmental indicators. The division of vulnerability into three sub-indices allows for an assessment of the driver(s) of vulnerability of a state and as such provides a foundation for drought mitigation and planning efforts. In addition, a probabilistic approach is used to investigate the sensitivity of vulnerability to the weighting scheme of indicators. The resulting geographic distribution of relative vulnerability of the states is partially a reflection of their heterogeneous climates but also highlights the importance of sustainable adaptation of the local economy to water availability in order to reduce sensitivity and to limit the impact of drought. As such, the study at hand offers insights to local and regional planners on how to effectively distribute funds and plan accordingly in order to reduce state-level drought vulnerability today and in the future.

Less to Lose? Drought Impact and Vulnerability Assessment in Disadvantaged Regions

Droughts hit the most vulnerable people the hardest. When this happens, everybody in the economy loses over the medium- to long-term. Proactive policies and planning based on vulnerability and risk assessments can reduce drought risk before the worst impacts occur. The aim of this article is to inform a global initiative, led by the United Nations Convention to Combat Desertification (UNCCD), to mitigate the effects of drought on vulnerable ecosystems and communities. This is approached through a rapid review of experiences from selected nations and of the available literature documenting methodological approaches to assess drought impacts and vulnerability at the local level. The review finds that members of the most vulnerable communities can integrate available methods to assess drought risks to their land and ecosystem productivity, their livelihoods and their life-supporting hydrological systems. This integration of approaches helps to ensure inclusive assessments across communities and ecosystems. However, global economic assessments often still fail to connect to holistic consideration of vulnerability at a local scale. As a result, they routinely fall short of capturing the systemic effects of land and water management decisions that deepen vulnerability to droughts over time. To ensure proactive and inclusive drought risk mitigation, multiscale, systemic approaches to drought vulnerability and risk assessment can be further reinforced at a global level.