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1.
Nature ; 569(7758): 649-654, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31142854

RESUMO

About 800 million people depend in part on meltwater from the thousands of glaciers in the high mountains of Asia. Water stress makes this region vulnerable to drought, but glaciers are a uniquely drought-resilient source of water. Here I show that seasonal glacier meltwater is equivalent to the basic needs of 221 ± 59 million people, or most of the annual municipal and industrial needs of Pakistan, Afghanistan, Tajikistan, Turkmenistan, Uzbekistan and Kyrgyzstan. During drought summers, meltwater dominates water inputs to the upper Indus, Aral and Chu/Issyk-Kul river basins. This reduces the risk of social instability, conflict and sudden migrations triggered by water scarcity, which is already associated with the large, rapidly growing populations and hydro-economies of these basins. Regional meltwater production is, however, unsustainably high-at 1.6 times the balance rate-and is expected to increase in future decades before ultimately declining. These results update and reinforce a previous publication in Nature on this topic, which was retracted after an inadvertent error was discovered.


Assuntos
Secas , Congelamento , Camada de Gelo/química , Abastecimento de Água/estatística & dados numéricos , Aclimatação , Ásia , Desidratação/prevenção & controle , Ecossistema , Humanos , Política , Chuva , Rios , Estações do Ano , Temperatura
2.
Stud Fam Plann ; 55(1): 5-21, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38414154

RESUMO

The interplay between population dynamics and the environment has long interested demographers. Although studies have explored how climate patterns affect macrolevel population processes, such as mortality and migration, little is known about their impact on individual-level demographic behaviors. This study fills this research gap by examining the linkages between exposure to drought and women's fertility preferences and contraceptive behaviors in sub-Saharan Africa. We analyze data from the Demographic and Health Surveys Program, focusing on 17 countries in East, Southern, and West Africa. We investigate whether women's recent exposure to drought episodes in their community affects their fertility preferences and modern contraceptive use. Generally, the findings show that drought is relevant to understanding women's fertility preferences and behaviors in the vast majority of countries; however, drought exposure has variable impacts. Moreover, whereas in some countries, drought exposure encourages contraceptive behaviors that align with women's preferences, in select countries it is associated with behavior that is misaligned with women's stated preferences. Overall, the study emphasizes the importance of examining climate events as complex forces that have localized meanings for demographic outcomes.


Assuntos
Comportamento Contraceptivo , Secas , Feminino , Humanos , Fertilidade , Anticoncepcionais , Dinâmica Populacional , Serviços de Planejamento Familiar
3.
Annu Rev Public Health ; 44: 213-232, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36623928

RESUMO

Extreme weather events are expected to increase due to climate change, which could pose an additional burden of morbidity and mortality. In recent decades, drought severity has increased in several regions around the world, affecting health by increasing the risk of water-, food-, and vector-borne diseases, malnutrition, cardiovascular and respiratory illness, mental health disorders, and mortality. Drought frequency and severity are expected to worsen across large regions as a result of a decrease in precipitation and an increase in temperature and atmospheric evaporative demand, posing a pressing challenge for public health. Variation in impacts among countries and communities is due to multiple factors, such as aging, socioeconomic status, access to health care, and gender, affecting population resilience. Integrative proactive action plans focused on risk management are required, and resources should be transferred to developing countries to reduce their vulnerability and risk.


Assuntos
Secas , Saúde Pública , Humanos , Mudança Climática
4.
Glob Chang Biol ; 29(18): 5304-5320, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37376714

RESUMO

Ecological restoration projects (ERPs) are an indispensable component of natural climate solutions and have proven to be very important for reversing environmental degradation in vulnerable regions and enhancing ecosystem services. However, the level of enhancement would be inevitably influenced by global drought and rising CO2 , which remain less investigated. In this study, we took the Beijing-Tianjin sand source region (which has experienced long-term ERPs), China, as an example and combined the process-based Biome-BGCMuSo model to set multiple scenarios to address this issue. We found ERP-induced carbon sequestration (CS), water retention (WR), soil retention (SR), and sandstorm prevention (SP) increased by 22.21%, 2.87%, 2.35%, and 28.77%, respectively. Moreover, the ecosystem services promotion from afforestation was greater than that from grassland planting. Approximately 91.41%, 98.13%, and 64.51% of the increased CS, SR, and SP were contributed by afforestation. However, afforestation also caused the WR to decline. Although rising CO2 amplified ecosystem services contributed by ERPs, it was almost totally offset by drought. The contribution of ERPs to CS, WR, SR, and SP was reduced by 5.74%, 32.62%, 11.74%, and 14.86%, respectively, under combined drought and rising CO2 . Our results confirmed the importance of ERPs in strengthening ecosystem services provision. Furthermore, we provide a quantitative way to understand the influence rate of drought and rising CO2 on ERP-induced ecosystem service dynamics. In addition, the considerable negative climate change impact implied that restoration strategies should be optimized to improve ecosystem resilience to better combat negative climate change impacts.


Assuntos
Dióxido de Carbono , Ecossistema , Secas , China , Pequim , Solo , Mudança Climática
5.
Oecologia ; 201(2): 323-339, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36692692

RESUMO

Understanding climate change impacts on the Cape Floristic Region requires improved knowledge of plant physiological responses to the environment. Studies examining physiological responses of mountain fynbos have consisted of campaign-based measurements, capturing snapshots of plant water relations and photosynthesis. We examine conclusions drawn from prior studies by tracking in situ physiological responses of three species, representing dominant growth forms (proteoid, ericoid, restioid), over 2 years using miniature continuous sap flow technology, long-term observations of leaf/culm water potential and gas exchange, and xylem vulnerability to embolism. We observed considerable inter-specific variation in the timing and extent of seasonal declines in productivity. Shallow-rooted Erica monsoniana exhibited steep within-season declines in sap flow and water potentials, and pronounced inter-annual variability in total daily sap flux (Js). Protea repens showed steady reductions in Js across both years, despite deeper roots and less negative water potentials. Cannomois congesta-a shallow-rooted restioid-was least negatively impacted. Following rehydrating rain at the end of summer, gas exchange recovery was lower in the drier year compared with the normal year, but did not differ between species. Loss of function in the drier year was partially accounted for by loss of xylem transport capacity in Erica and Cannomois, but not Protea. Hitherto unseen water use patterns, including inter-annual variability of gas exchange associated with contrasting water uptake properties, reveal that species use different mechanisms to cope with summer dry periods. Revealing physiological responses of key growth forms enhances predictions of plant function within mountain fynbos under future conditions.


Assuntos
Fenômenos Fisiológicos Vegetais , Água , Água/fisiologia , Folhas de Planta/fisiologia , Fotossíntese , Estações do Ano , Secas , Árvores/fisiologia
6.
Planta ; 256(5): 97, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36219256

RESUMO

MAIN CONCLUSION: Drought may be efficiently managed using the following strategies: prevention, mitigation, readiness, recovery, and transformation. Biotechnological interventions may become highly important in reducing plants' drought stress in order to address key plant challenges such as population growth and climate change. Drought is a multidimensional construct with several triggering mechanisms or contributing factors working at various spatiotemporal scales, making it one of the known natural catastrophes. Drought is among the causes of hunger and malnutrition, decreasing agricultural output, and poor nutrition. Many deaths caused in children are due to hunger situations, and one in four children face stunted growth. All this hunger and malnutrition may be responsible for the reduction in agricultural productivity caused due to the drought situations affecting food security. Global Hunger Index has been accelerating due to under-nutrition and under-5 deaths. Drought has been covering more than 20% of the world's agricultural areas, leading to significantly less food production than what is required for consumption. Drought reduces soil fertility and adversely affects soil biological activity reducing the inherent capacity of the soil to support vegetation. Recent droughts have had a much greater effect on people's lives, even beyond causing poverty and hunger. Drought may have substantial financial consequences across the globe it may cause a severe impact on the world economy. It is a natural feature of the environment that will appear and disappear as it has in history. Due to increasing temperatures and growing vulnerabilities, it will undoubtedly occur more often and seriously in the coming years. To ensure sustainable socio-economic and social development, it is critical to reducing the effects of potential droughts worldwide using different biotechnological interventions. It's part of a long-term growth plan, and forecasting is essential for early warnings and global hunger management.


Assuntos
Fome , Desnutrição , Secas , Abastecimento de Alimentos , Desnutrição/epidemiologia , Desnutrição/prevenção & controle , Solo
10.
BMC Public Health ; 21(1): 1501, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-34344335

RESUMO

BACKGROUND: Climate-induced disruptions like drought can destabilize household and community livelihoods, particularly in low- and middle-income countries. This qualitative study explores the impact of severe and prolonged droughts on gendered livelihood transitions, women's social and financial wellbeing, and sexual and reproductive health (SRH) outcomes in two Zambian provinces. METHODS: In September 2020, in-depth interviews (n = 20) and focus group discussions (n = 16) with 165 adult women and men in five drought-affected districts, as well as key informant interviews (n = 16) with civic leaders and healthcare providers, were conducted. A team-based thematic analysis approach, guided by the Framework Method, was used to code transcript text segments, facilitating identification and interpretation of salient thematic patterns. RESULTS: Across districts, participants emphasized the toll drought had taken on their livelihoods and communities, leaving farming households with reduced income and food, with many turning to alternative income sources. Female-headed households were perceived as particularly vulnerable to drought, as women's breadwinning and caregiving responsibilities increased, especially in households where women's partners out-migrated in search of employment prospects. As household incomes declined, women and girls' vulnerabilities increased: young children increasingly entered the workforce, and young girls were married when families could not afford school fees and struggled to support them financially. With less income due to drought, many participants could not afford travel to health facilities or would resort to purchasing health commodities, including family planning, from private retail pharmacies when unavailable from government facilities. Most participants described changes in fertility intentions motivated by drought: women, in particular, expressed desires for smaller families, fearing drought would constrain their capacity to support larger families. While participants cited some ongoing activities in their communities to support climate change adaptation, most acknowledged current interventions were insufficient. CONCLUSIONS: Drought highlighted persistent and unaddressed vulnerabilities in women, increasing demand for health services while shrinking household resources to access those services. Policy solutions are proposed to mitigate drought-induced challenges meaningfully and sustainably, and foster climate resilience.


Assuntos
Secas , Saúde Reprodutiva , Adulto , Criança , Pré-Escolar , Serviços de Planejamento Familiar , Feminino , Fertilidade , Humanos , Masculino , Zâmbia
17.
Ecotoxicol Environ Saf ; 180: 63-72, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31075717

RESUMO

In the present study, a potent Aluminum (Al) resistant yeast strain CAM4 was isolated from rhizosphere soil of Rubus geoides, grown in acidic Andisols and identified as Rhodotorula mucilaginosa by 18S rRNA gene sequence analysis. The strain CAM4 was selected in terms of abiotic stress tolerance to Al, salinity and drought with multiple plant growth promoting (PGP) traits. Besides, strain CAM4 also exhibited Al removal efficiency (80-88%) from the culture medium even under combined stresses of salinity and drought. The sawdust-based formulation of strain CAM4 (sawdust-molasses 5%-PEG 1%-strain CAM4) showed higher cell viability of up to 24 weeks (8.54 log CFU g-1). Inoculation of formulated strain CAM4 significantly enhanced the various morphological and biochemical characters of Lactuca sativa grown under abiotic stress conditions. The formulated strain CAM4 also reduced the accumulation of Al in L. sativa as well that conferring Al tolerance to the plants. The study concludes that strain CAM4 could be used as a biofertilizer for healthy and safe crop production in soils, with Al toxicity as well as combined salt and drought stresses.


Assuntos
Alumínio/toxicidade , Secas , Lactuca/efeitos dos fármacos , Rhodotorula/crescimento & desenvolvimento , Salinidade , Microbiologia do Solo , Estresse Fisiológico/efeitos dos fármacos , Lactuca/crescimento & desenvolvimento , Rizosfera , Solo/química
18.
Am J Public Health ; 108(S2): S114-S119, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29072936

RESUMO

Anthropogenic activity will bring immediate changes and disruptions to the global climate with accompanying health implications. Although policymakers and public health advocates are beginning to acknowledge the health implications of climate change, current policy approaches are lagging behind. We proposed that 4 key policy principles are critical to successful policymaking in this arena: mainstreaming, linking mitigation and adaptation policy, applying population perspectives, and coordination. We explored California's progress in addressing the public health challenges of climate change in the San Joaquin Valley as an example. We discussed issues of mental health and climate change, and used the San Joaquin Valley of California as an example to explore policy approaches to health issues and climate change. The California experience is instructive for other jurisdictions.


Assuntos
Mudança Climática , Formulação de Políticas , Saúde Pública/legislação & jurisprudência , California , Secas , Poluição Ambiental/prevenção & controle , Fazendeiros , Gases de Efeito Estufa , Temperatura Alta/efeitos adversos , Humanos , Transtornos Mentais/epidemiologia , Exposição Ocupacional/efeitos adversos
20.
Glob Chang Biol ; 23(10): 4185-4203, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28614633

RESUMO

Climate change will affect semiarid ecosystems through severe droughts that increase the competition for resources in plant and microbial communities. In these habitats, adaptations to climate change may consist of thinning-that reduces competition for resources through a decrease in tree density and the promotion of plant survival. We deciphered the functional and phylogenetic responses of the microbial community to 6 years of drought induced by rainfall exclusion and how forest management affects its resistance to drought, in a semiarid forest ecosystem dominated by Pinus halepensis Mill. A multiOMIC approach was applied to reveal novel, community-based strategies in the face of climate change. The diversity and the composition of the total and active soil microbiome were evaluated by 16S rRNA gene (bacteria) and ITS (fungal) sequencing, and by metaproteomics. The microbial biomass was analyzed by phospholipid fatty acids (PLFAs), and the microbially mediated ecosystem multifunctionality was studied by the integration of soil enzyme activities related to the cycles of C, N, and P. The microbial biomass and ecosystem multifunctionality decreased in drought-plots, as a consequence of the lower soil moisture and poorer plant development, but this decrease was more notable in unthinned plots. The structure and diversity of the total bacterial community was unaffected by drought at phylum and order level, but did so at genus level, and was influenced by seasonality. However, the total fungal community and the active microbial community were more sensitive to drought and were related to ecosystem multifunctionality. Thinning in plots without drought increased the active diversity while the total diversity was not affected. Thinning promoted the resistance of ecosystem multifunctionality to drought through changes in the active microbial community. The integration of total and active microbiome analyses avoids misinterpretations of the links between the soil microbial community and climate change.


Assuntos
Mudança Climática , Secas , Microbiologia do Solo , Bactérias , Ecossistema , Florestas , Filogenia , RNA Ribossômico 16S , Solo , Água
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