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1.
Proc Natl Acad Sci U S A ; 121(21): e2312519121, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38739799

RESUMO

Drawing on a harmonized longitudinal dataset covering more than 55,000 smallholder farms in six African countries, we analyze changes in crop productivity from 2008 to 2019. Because smallholder farmers represent a significant fraction of the world's poorest people, agricultural productivity in this context matters for poverty reduction and for the broader achievement of the UN Sustainable Development Goals. Our analysis measures productivity trends for nationally representative samples of smallholder crop farmers, using detailed data on agricultural inputs and outputs which we integrate with detailed data on local weather and environmental conditions. In spite of government commitments and international efforts to strengthen African agriculture, we find no evidence that smallholder crop productivity improved over this 12-y period. Our preferred statistical specification of total factor productivity (TFP) suggests an overall decline in productivity of -3.5% per year. Various other models we test also find declining productivity in the overall sample, and none of them finds productivity growth. However, the different countries in our sample experienced varying trends, with some instances of growth in some regions. The results suggest that major challenges remain for agricultural development in sub-Saharan Africa. They complement previous analyses that relied primarily on aggregate national statistics to measure agricultural productivity, rather than detailed microdata.


Assuntos
Agricultura , Produtos Agrícolas , África Subsaariana , Produtos Agrícolas/crescimento & desenvolvimento , Agricultura/métodos , Agricultura/tendências , Humanos , Produção Agrícola/estatística & dados numéricos , Produção Agrícola/tendências , Fazendeiros/estatística & dados numéricos , Fazendas , Desenvolvimento Sustentável/tendências
2.
Environ Res ; 252(Pt 3): 118784, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38555984

RESUMO

The escalating trend of greenhouse gas emissions presents a dual threat to both food security and the exacerbation of global warming. Addressing this pressing issue demands concerted efforts on local and global scales to champion sustainable food production and foster environmental benefits. In 2015, a pivotal field experiment was conducted in the North China Plain, aiming to delineate the intricate balance between agricultural productivity and environmental stewardship. This study comprised eight meticulously designed treatments, incorporating two key components: the evaluation of economic and environmental parameters encompassing carbon footprint, energy consumption, and the carbon sustainability index. Notably, while the carbon sustainability index exhibited improvement, it also revealed a 9.4% increase in emissions compared to the baseline, underscoring the nuanced trade-offs involved. The findings underscored the efficacy of no-tillage (NT) practices coupled with soybean-based crop rotation, mitigating yield reduction compared to conventional tillage (RT). However, the optimal yield was observed in the RT-MW treatment, amalgamating conventional tillage with minimum tillage practices. Moreover, despite the higher cost associated with soybeans relative to milled wheat, their cultivation yielded a notable increase in net income. These compelling results advocate for the adoption of conservation agriculture as a means to optimize the delicate equilibrium between environmental preservation and economic prosperity. Furthermore, the study underscores the imperative for further research endeavors aimed at devising highly productive agricultural systems that seamlessly integrate environmental sustainability with economic viability, echoing the crucial insights gleaned from analogous contexts.


Assuntos
Agricultura , Pegada de Carbono , Conservação dos Recursos Naturais , China , Agricultura/economia , Agricultura/métodos , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/economia , Pegada de Carbono/economia , Glycine max/crescimento & desenvolvimento
3.
Proc Natl Acad Sci U S A ; 118(8)2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33593895

RESUMO

Soil erosion in agricultural landscapes reduces crop yields, leads to loss of ecosystem services, and influences the global carbon cycle. Despite decades of soil erosion research, the magnitude of historical soil loss remains poorly quantified across large agricultural regions because preagricultural soil data are rare, and it is challenging to extrapolate local-scale erosion observations across time and space. Here we focus on the Corn Belt of the midwestern United States and use a remote-sensing method to map areas in agricultural fields that have no remaining organic carbon-rich A-horizon. We use satellite and LiDAR data to develop a relationship between A-horizon loss and topographic curvature and then use topographic data to scale-up soil loss predictions across 3.9 × 105 km2 of the Corn Belt. Our results indicate that 35 ± 11% of the cultivated area has lost A-horizon soil and that prior estimates of soil degradation from soil survey-based methods have significantly underestimated A-horizon soil loss. Convex hilltops throughout the region are often completely denuded of A-horizon soil. The association between soil loss and convex topography indicates that tillage-induced erosion is an important driver of soil loss, yet tillage erosion is not simulated in models used to assess nationwide soil loss trends in the United States. We estimate that A-horizon loss decreases crop yields by 6 ± 2%, causing $2.8 ± $0.9 billion in annual economic losses. Regionally, we estimate 1.4 ± 0.5 Pg of carbon have been removed from hillslopes by erosion of the A-horizon, much of which likely remains buried in depositional areas within the fields.


Assuntos
Carbono/análise , Produtos Agrícolas/crescimento & desenvolvimento , Ecossistema , Solo/química , Zea mays/crescimento & desenvolvimento , Meio-Oeste dos Estados Unidos
4.
Environ Geochem Health ; 46(4): 128, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483731

RESUMO

Extreme climates and the unpredictability of the weather are significant obstacles to agricultural productivity. This study is the first attempt to explore the capacity of nanobonechar (NBC) for promoting climate-smart agriculture. A pot experiment was performed on maize (Zea mays L.) under a deficit irrigation system (40, 70, and 100% irrigation rates) using different soil application rates of the NBC (0, 0.5, 1, and 2% wt/wt). Additionally, the CO2-C efflux rate and cumulative CO2-C were measured in an incubation experiment. The results indicated the best performance of the 1% NBC treatment under a 70% irrigation rate in terms of the fresh and dry weights of maize plants. Total PO43- and Ca2+ were significantly higher in the plants grown in the NBC-amended soil as compared to the control, showing a gradual increase with an increase in the NBC application rate. The improved productivity of maize plants under a deficit irrigation system was associated with enhanced water-holding capacity, organic matter, and bioavailability of cations (Ca2+, K+, and Na+) and anions (PO43- and NO3-) in the soils amended with NBC. The CO2-C efflux rate and cumulative CO2-C emissions remain higher in the NBC-amended soil than in the un-amended soil, pertaining to the high contents of soil organic matter emanating from the NBC. We conclude that NBC could potentially be used as a soil amendment for promoting maize growth under a water stress condition.


Assuntos
Agricultura , Dióxido de Carbono , Dióxido de Carbono/análise , Solo , Clima , Zea mays
5.
Sensors (Basel) ; 23(4)2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36850471

RESUMO

Smart sensing devices enabled hydroponics, a concept of vertical farming that involves soilless technology that increases green area. Although the cultivation medium is water, hydroponic cultivation uses 13 ± 10 times less water and gives 10 ± 5 times better quality products compared with those obtained through the substrate cultivation medium. The use of smart sensing devices helps in continuous real-time monitoring of the nutrient requirements and the environmental conditions required by the crop selected for cultivation. This, in turn, helps in enhanced year-round agricultural production. In this study, lettuce, a leafy crop, is cultivated with the Nutrient Film Technique (NFT) setup of hydroponics, and the growth results are compared with cultivation in a substrate medium. The leaf growth was analyzed in terms of cultivation cycle, leaf length, leaf perimeter, and leaf count in both cultivation methods, where hydroponics outperformed substrate cultivation. The results of the 'AquaCrop simulator also showed similar results, not only qualitatively and quantitatively, but also in terms of sustainable growth and year-round production. The energy consumption of both the cultivation methods is compared, and it is found that hydroponics consumes 70 ± 11 times more energy compared to substrate cultivation. Finally, it is concluded that smart sensing devices form the backbone of precision agriculture, thereby multiplying crop yield by real-time monitoring of the agronomical variables.


Assuntos
Conservação de Recursos Energéticos , Lactuca , Hidroponia , Fenômenos Físicos , Água
6.
J Environ Manage ; 347: 119147, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37776793

RESUMO

In recent decades, Technology and Innovation (TI) have shown tremendous potential for improving agricultural productivity and environmental sustainability. However, the adoption and implementation of TI in the agricultural sector and its impact on the environment remain limited. To gain deeper insights into the significance of TI in enhancing agricultural productivity while maintaining environmental balance, this study investigates 21 agriculture-dependent Asian countries. Two machine learning techniques, LASSO (Least Absolute Shrinkage and Selection Operator) and Elastic-Net, are employed to analyze the data, which is categorized into three regional groups: ASEAN (Association of Southeast Asian Nations), SAARC (South Asian Association for Regional Cooperation), and GCC (Gulf Cooperation Council). The findings of this study highlight the heterogeneous nature of technology adoption and its environmental implications across the three country groups. ASEAN countries emerge as proactive adopters of relevant technologies, effectively enhancing agricultural production while simultaneously upholding environmental quality. Conversely, SAARC countries exhibit weaker technology adoption, leading to significant fluctuations in environmental quality, which in turn impact agricultural productivity. Notably, agricultural emissions of N2O (nitrous oxide) and CO2 (carbon dioxide) in SAARC countries show a positive association with agricultural production, while CH4 (methane) emissions have an adverse effect. In contrast, the study reveals a lack of evidence regarding technological adoption in agriculture among GCC countries. Surprisingly, higher agricultural productivity in these countries is correlated with increased N2O emissions. Moreover, the results indicate that deforestation and expansion of cropland contribute to increased agricultural production; however, this expansion is accompanied by higher emissions related to agricultural activities. This research represents a pioneering empirical analysis of the impact of TI and environmental emission gases on agricultural productivity in the three aforementioned country groups. It underscores the imperative of embracing relevant technologies to enhance agricultural output while concurrently ensuring environmental sustainability. The findings of this study provide valuable insights for policymakers and stakeholders in formulating strategies to promote sustainable agriculture and technological advancement in the context of diverse regional dynamics.


Assuntos
Gases de Efeito Estufa , Gases de Efeito Estufa/análise , Solo , Agricultura/métodos , Gases , Dióxido de Carbono/análise , Tecnologia , Metano/análise , Óxido Nitroso/análise
7.
J Sci Food Agric ; 103(6): 2715-2726, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36066551

RESUMO

In this study, the impacts of small-scale farmers on food security enhancement were estimated in three dimensions of food availability, food access and food utilization. In the current study, a systematic review and meta-analysis have been performed to synthesize results from 75 original articles. It includes the pooling of data that quantitatively investigate whether or not causal links characterized in the original articles remain valid across a broader scope of the literature. The findings show that farmers who are small-scale in natural/physical capital would lead to higher median food production and agricultural productivity, compared with small-scale farmers in financial capital, at about 19% and 15%, respectively. Meta-regression results indicate that small-scale farmers in natural/physical capital have significantly positive effects on the average agricultural productivity, food income and biofortification. By contrast, farmers who are small-scale in financial capital have negative effects on food security. The influential role of these small-scale farmers should also be considered since food insecurity leads to socio-economic implications. Therefore, it is recommended to cultivate higher value crops, to participate in various income-generating activities such as fisheries and forestry, and to pay agricultural credits. The effect of the size of small-scale farmers on global food security is very useful for policymakers to plan for a world without hunger. © 2022 Society of Chemical Industry.


Assuntos
Fazendeiros , Abastecimento de Alimentos , Humanos , Agricultura/métodos , Renda , Segurança Alimentar
8.
World Dev ; 146: 105592, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34602709

RESUMO

The relationship between farm size and productivity has been studied extensively in the agricultural and development economics literature. However, most of the documented evidence in sub-Saharan Africa (SSA) is based on samples of small-scale farms operating 5 ha or less, with very little evidence assessing this relationship over a wider range of farm sizes. This omission is especially important considering the rapid expansion of medium-scale farms in much of Africa. This study examines the farm size-productivity relationship over a range of farms between zero and 40 ha in Nigeria. It also tests whether there is heterogeneity in productivity within medium-scale farms depending on how they came into being. Using four measures of productivity, empirical estimates reveal a U-shaped relationship where the IR holds between zero and about 22 ha, turning positive afterwards. Moreover, when medium-scale farms are distinguished between those who were actively engaged as small-scale farmers and stepped up/expanded their scale of operation and those who were primarily in non-farm employment and later stepped into medium-scale farming, the turning point for farmers who stepped up into medium-scale farming is at 11 ha, in contrast to 22 ha for those who stepped in. Further evidence suggests heterogeneity in productivity within medium-scale farms depending on whether the owner-operators stepped up or stepped into medium-scale farming. These findings imply that policies facilitating smallholders' ability to expand the scale of their activities could contribute substantially to growth in farm productivity, agricultural commercialization and increase in food security in Nigeria, although in most areas only a small proportion of smallholder households are in a position to do this.

9.
Proc Natl Acad Sci U S A ; 114(34): 8939-8944, 2017 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-28028219

RESUMO

Urban expansion often occurs on croplands. However, there is little scientific understanding of how global patterns of future urban expansion will affect the world's cultivated areas. Here, we combine spatially explicit projections of urban expansion with datasets on global croplands and crop yields. Our results show that urban expansion will result in a 1.8-2.4% loss of global croplands by 2030, with substantial regional disparities. About 80% of global cropland loss from urban expansion will take place in Asia and Africa. In both Asia and Africa, much of the cropland that will be lost is more than twice as productive as national averages. Asia will experience the highest absolute loss in cropland, whereas African countries will experience the highest percentage loss of cropland. Globally, the croplands that are likely to be lost were responsible for 3-4% of worldwide crop production in 2000. Urban expansion is expected to take place on cropland that is 1.77 times more productive than the global average. The loss of cropland is likely to be accompanied by other sustainability risks and threatens livelihoods, with diverging characteristics for different megaurban regions. Governance of urban area expansion thus emerges as a key area for securing livelihoods in the agrarian economies of the Global South.


Assuntos
Agricultura/tendências , Produtos Agrícolas/crescimento & desenvolvimento , Previsões , Urbanização/tendências , África , Agricultura/métodos , Ásia , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/estatística & dados numéricos , Conservação dos Recursos Naturais/tendências , Geografia
10.
Land use policy ; 85: 104-113, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31217652

RESUMO

Smallholder farmers in the mid-hills of Nepal are facing an acute labor shortage due to out-migration which, in general, has affected the capacity to achieve timely crop establishment, harvest, and inter-cultural operations. These effects are more visible in the case of labor-intensive crops such as rice and promoting higher levels of rural mechanization has emerged as the primary policy response option. Nevertheless, quantitative evidence for the ability of mechanization to offset the adverse effects of shortages increasing labor prices in these systems is largely absent. This study investigates the impacts associated with adoption of mini-tillers (5 to 9 horsepower) for land preparation on smallholder rice productivity in the mid-hills of Nepal. We use an endogenous switching regression that accounts for both observed and unobserved sources of heterogeneity between mini-tiller adopters and non-adopters. Findings demonstrate that rising on-farm rural wage rates and an emerging decline in draft animal availability are driving adoption of the mini-tiller. Among users, the mini-tiller increased rice productivity by 1,110 kg/ha (27%). Further, regression results suggest that mini-tiller non-adopters would be able to increase their rice productivity by 1,250 kg/ha (26%) if they adopt. Moreover, our analysis revealed that very small farms (≤0.25 ha) that adopt mini-tillers are benefited the most in terms of gains in rice productivity. These findings support policies that favor the expansion of small-scale mechanization in the hill production ecologies of South Asia and highlight the need to foster the emergence of an associated service economy that will permit smallholders access to capital-intensive machinery such as the mini-tiller.

11.
Food Policy ; 86: 101721, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31417206

RESUMO

Increased fertilizer use will likely be crucial for raising and sustaining farm productivity in Africa, but adoption may be limited by ineffectiveness under certain conditions. This article quantifies the impacts of soil characteristics on maize response to fertilizer in Zambia using a nationally representative sample of 1453 fields, combining economic, farm management and soil analysis data. Depending on soil regimes, average maize yield response estimates range from insignificant (0) to 7 maize kg per fertilizer kg. For the majority of farmers, the estimated average value cost ratio is between 1 and 2, meaning fertilizer use would be fiscally rational, barring uncertainty and transfer costs. Since transfer costs exist and outcomes are uncertain, however, many farmers may sensibly pause before deciding whether to adopt fertilizer. This suggests shifting the emphasis of chronically low fertilizer use in Africa away from explanations of "market failure" toward greater emphasis on improving fertilizer efficacy.

12.
Proc Natl Acad Sci U S A ; 111(9): 3274-9, 2014 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-24344285

RESUMO

Agricultural production is sensitive to weather and thus directly affected by climate change. Plausible estimates of these climate change impacts require combined use of climate, crop, and economic models. Results from previous studies vary substantially due to differences in models, scenarios, and data. This paper is part of a collective effort to systematically integrate these three types of models. We focus on the economic component of the assessment, investigating how nine global economic models of agriculture represent endogenous responses to seven standardized climate change scenarios produced by two climate and five crop models. These responses include adjustments in yields, area, consumption, and international trade. We apply biophysical shocks derived from the Intergovernmental Panel on Climate Change's representative concentration pathway with end-of-century radiative forcing of 8.5 W/m(2). The mean biophysical yield effect with no incremental CO2 fertilization is a 17% reduction globally by 2050 relative to a scenario with unchanging climate. Endogenous economic responses reduce yield loss to 11%, increase area of major crops by 11%, and reduce consumption by 3%. Agricultural production, cropland area, trade, and prices show the greatest degree of variability in response to climate change, and consumption the lowest. The sources of these differences include model structure and specification; in particular, model assumptions about ease of land use conversion, intensification, and trade. This study identifies where models disagree on the relative responses to climate shocks and highlights research activities needed to improve the representation of agricultural adaptation responses to climate change.


Assuntos
Agricultura/economia , Mudança Climática , Produtos Agrícolas/crescimento & desenvolvimento , Modelos Econômicos , Dióxido de Carbono/análise , Comércio/estatística & dados numéricos , Simulação por Computador , Previsões , Humanos
13.
Crop Prot ; 98: 94-101, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28775391

RESUMO

The parasitic weed Striga hermonthica Benth. (Orobanchaceae), commonly known as striga, is an increasingly important constraint to cereal production in sub-Saharan Africa (SSA), often resulting in total yield losses in maize (Zea mays L.) and substantial losses in sorghum (Sorghum bicolor (L.) Moench). This is further aggravated by soil degradation and drought conditions that are gradually becoming widespread in SSA. Forage legumes in the genus Desmodium (Fabaceae), mainly D. uncinatum and D. intortum, effectively control striga and improve crop productivity in SSA. However, negative effects of climate change such as drought stress is affecting the functioning of these systems. There is thus a need to identify and characterize new plants possessing the required ecological chemistry to protect crops against the biotic stress of striga under such environmental conditions. 17 accessions comprising 10 species of Desmodium were screened for their drought stress tolerance and ability to suppress striga. Desmodium incanum and D. ramosissimum were selected as the most promising species as they retained their leaves and maintained leaf function for longer periods during their exposure to drought stress conditions. They also had desirable phenotypes with more above ground biomass. The two species suppressed striga infestation, both under controlled and field conditions, and resulted in significant grain yield increases, demonstrating the incremental capability of Desmodium species in striga suppression. These results demonstrate beneficial effects of Desmodium species in enhancing cereal productivity in dry areas.

14.
Popul Environ ; 38(3): 286-308, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28260827

RESUMO

This study investigates the effects of climatic variations and extremes captured by variability in temperature, precipitation, and incidents of typhoons on aggregate inter-provincial migration within the Philippines using panel data. Our results indicate that a rise in temperature and to some extent increased typhoon activity increase outmigration, while precipitation does not have a consistent, significant effect. We also find that temperature and typhoons have significant negative effects on rice yields, a proxy for agricultural productivity, and generate more outmigration from provinces that are more agriculturally dependent and have a larger share of rural population. Finally, migration decisions of males, younger individuals, and those with higher levels of education are more sensitive to rising temperature and typhoons. We conclude that temperature increase and to some extent typhoon activities promote migration, potentially through their negative effect on crop yields. The migration responses of males, more educated, and younger individuals are more sensitive to these climatic impacts.

15.
Proc Natl Acad Sci U S A ; 110(21): 8363-8, 2013 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-23671086

RESUMO

New estimates of the impacts of germplasm improvement in the major staple crops between 1965 and 2004 on global land-cover change are presented, based on simulations carried out using a global economic model (Global Trade Analysis Project Agro-Ecological Zone), a multicommodity, multiregional computable general equilibrium model linked to a global spatially explicit database on land use. We estimate the impact of removing the gains in cereal productivity attributed to the widespread adoption of improved varieties in developing countries. Here, several different effects--higher yields, lower prices, higher land rents, and trade effects--have been incorporated in a single model of the impact of Green Revolution research (and subsequent advances in yields from crop germplasm improvement) on land-cover change. Our results generally support the Borlaug hypothesis that increases in cereal yields as a result of widespread adoption of improved crop germplasm have saved natural ecosystems from being converted to agriculture. However, this relationship is complex, and the net effect is of a much smaller magnitude than Borlaug proposed. We estimate that the total crop area in 2004 would have been between 17.9 and 26.7 million hectares larger in a world that had not benefited from crop germplasm improvement since 1965. Of these hectares, 12.0-17.7 million would have been in developing countries, displacing pastures and resulting in an estimated 2 million hectares of additional deforestation. However, the negative impacts of higher food prices on poverty and hunger under this scenario would likely have dwarfed the welfare effects of agricultural expansion.


Assuntos
Agricultura , Produtos Agrícolas , Ecossistema , Abastecimento de Alimentos/economia , Modelos Teóricos , Pesquisa , Agricultura/economia , Agricultura/história , Agricultura/métodos , Produtos Agrícolas/economia , Produtos Agrícolas/crescimento & desenvolvimento , História do Século XX , História do Século XXI , Humanos , Fome , Pobreza/economia , Pobreza/história , Pesquisa/economia , Pesquisa/história
16.
J Environ Manage ; 150: 138-148, 2015 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25481499

RESUMO

The installation of deep drains is an engineering approach to remediate land salinised by the influence of shallow groundwater. It is a costly treatment and its economic viability is, in part, dependent on the lateral extent to which the drain increases biological productivity by lowering water tables and soil salinity (referred to as the drains' zone of benefit). Such zones may be determined by assessing the biological productivity response of adjacent vegetation over time. We tested a multi-temporal satellite remote sensing method to analyse temporal and spatial changes in vegetation condition surrounding deep drainage sites at five locations in the Western Australian wheatbelt affected by dryland salinity-Morawa, Pithara, Beacon, Narembeen and Dumbleyung. Vegetation condition as a surrogate for biological productivity was assessed by Normalised Difference Vegetation Index (NDVI) during the peak growing season. Analysis was at the site scale within a 1000 m buffer zone from the drains. There was clear evidence of NDVI increasing with elevation, slope and distance from the drain. After accounting for elevation, slope and distance from the drain, there was a significant increase in NDVI across the five locations after installation of deep drains. Changes in NDVI after drainage were broadly consistent with measured changes at each site in groundwater levels after installation of the deep drains. However, this study assessed the lateral extent of benefit for biological productivity and gave a measure of the area of benefit along the entire length of the drain. The method demonstrated the utility of spring NDVI images for rapid and relatively simple assessment of the change in site condition after implementation of drainage, but approaches for further improvement of the procedure were identified.


Assuntos
Monitoramento Ambiental/métodos , Água Subterrânea , Abastecimento de Água , Austrália , Recuperação e Remediação Ambiental , Humanos , Tecnologia de Sensoriamento Remoto , Salinidade , Estações do Ano
17.
Integr Environ Assess Manag ; 20(3): 794-804, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37859513

RESUMO

Climate information service (CIS) is a key component of a climate adaptation strategy that is expected to lessen climate risk. Access to and use of CIS among the local community are limited and constrained by various factors and are not supported by empirical research evidence. Therefore, this article analyzed CIS access and use determinants among smallholder farmers in Bereh woreda. The study applied a cross-sectional design with a mixed methodological approach. Data were collected through a survey of 219 smallholder farmer households, three focused-group discussions, and six key informant interviews. The collected survey data were analyzed using the heckprobit model to determine factors influencing smallholder farmers' access to and use of CIS. The heckprobit model results revealed that the determinants of CIS access and use had a statistical significance of log-likelihood of 1% (Wald χ2 = 45.2, p = 0.001), indicating a strong explanatory power. The selection model revealed that age and off-farm income significantly reduced the likelihood of accessing CIS, whereas mobile-phone ownership and male-headed households increased the likelihood of accessing it. Age, female-headed households, and farm size decreased the likelihood of using CIS, whereas mixed farming, radio ownership, and access to herbicide enhanced the likelihood of using it. This study, therefore, recommends intensive awareness creation and improving the delivery of diverse and reliable CIS to enhance agricultural productivity and smallholder farmers' resilience to the impacts of climate change. Integr Environ Assess Manag 2024;20:794-804. © 2023 SETAC.

18.
Plants (Basel) ; 13(17)2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39273929

RESUMO

The bioavailability of heavy metals in soil is a crucial factor in determining their potential uptake by plants and their subsequent entry into the food chain. Various methods, including traditional chemical extractants and the diffusive gradients in thin films (DGT) technique, are employed to assess this bioavailability. The bioavailability of heavy metals, particularly cadmium (Cd) and lead (Pb), is also influenced by soil texture and their concentrations in the soil solution. The primary objectives of this experiment were to compare and correlate the assessment of the Cd and Pb bioavailability using the DGT technique and traditional extractants across two soil textural classes: sandy clay loam (SCL) and clay loam (CL) at two contamination levels: aged contaminated (NC) and artificially contaminated (AC). The specific objectives included assessing the bioavailability of Cd and Pb at different growth stages of the wheat plant and correlating the DGT-based bioassessments of Cd and Pb with their concentrations in various plant parts at different growth stages. This study also compared the effectiveness of the DGT method and traditional extraction techniques in assessing the bioavailable fractions of Cd and Pb in soil. The regression analysis demonstrated strong positive correlations between the DGT method and various extraction methods. The results showed that the wheat plants grown in the AC soils exhibited lower root, shoot, and grain weights compared to those grown in the NC soils, indicating that metal contamination negatively impacts plant performance. The concentrations of Cd and Pb in the wheat tissues varied across different growth stages, with the highest levels observed during the grain filling (S3) and maturity (S4) stages. It is concluded that the in situ assessment of Cd and Pb though DGT was strongly and positively correlated with the Cd and Pb concentration in wheat plant parts at the maturity stage. A correlation and regression analysis of the DGT assessment and traditional extractants showed that the DGT method provides a reliable tool for assessing the bioavailability of Cd and Pb in soils and helped in developing sustainable soil management strategies to ensure the safety of agricultural products for human consumption.

19.
Ecol Evol ; 14(5): e11332, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38756681

RESUMO

Parasitic weeds in the genera Orobanche, Phelipanche (broomrapes) and Striga (witchweeds) have a devastating impact on food security across much of Africa, Asia and the Mediterranean Basin. Yet, how climatic factors might affect the range expansion of these weeds in the context of global environmental change remains unexplored. We examined satellite-based environmental variables such as surface temperature, root zone soil moisture, and elevation, in relation to parasitic weed distribution and environmental conditions over time, in combination with observational data from the Global Biodiversity Information Facility (GBIF). Our analysis reveals contrasting environmental and altitude preferences in the genera Striga and Orobanche. Asiatic witchweed (Striga asiatica), which infests corn, rice, sorghum, and sugar cane crops, appears to be expanding its range in high elevation habitats. It also shows a significant association with heat-moisture coupling events, the frequency of which is rising in such environments. These results point to geographical shifts in distribution and abundance in parasitic weeds due to climate change.

20.
Heliyon ; 10(14): e34749, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39130470

RESUMO

Climate change is an imminent threat, particularly affecting agricultural productivity, which relies heavily on weather conditions. Understanding the specific impacts of climate change on key crops is crucial for developing effective adaptation strategies to ensure food security. The growth patterns of onions and garlic were observed at over ten different locations in South Korea, and the yield data from the past 40 years were analyzed. The yield was significantly correlated with temperature and strongly affected by the frequent and unexpected patterns of precipitation. The increase in mean temperature during winter and the spatial and temporal concentration of precipitation are expected to be the most influential factors for Allium crop production in the future. In addition, the yields of onions and garlic can serve as good indicators for predicting the impacts of weather on agricultural productivity, given their extended cultivation periods and significant correlations with temperature and precipitation. As climate change scenarios become available, the results of this study can serve as a basis for predicting changes in agricultural production in the future and identifying opportunities to adapt cultivation systems for food security.

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