A scenario modelling approach to assess management impacts on soil erosion in coffee systems in Central America

Soil erosion is one of the major causes of soil degradation worldwide, because it causes the depletion of soil organic carbon, nutrients, and water holding capacity. In Central America, coffee production is vulnerable to soil erosion since it often occupies steep slopes with high annual precipitation. To assess management options to control erosion, soil and vegetation field data were collected from 90 Costa Rican and 96 Guatemalan coffee plantations, mainly shaded, distributed in six coffee production areas. Soil erosion was modelled using the RUSLE (Revised Universal Soil Loss Equation), integrating soil and vegetation cover field data, with remote sensing data. Management scenarios were developed to assess the role of two principal coffee management strategies in mitigating soil erosion: increasing vegetation cover, and soil conservation practices. Average estimated erosion rates of 17 and 7 Mg ha−1 yr−1 were predicted for plantations of Costa Rica and Guatemala, respectively, with erosion from coffee plantations representing between 23% and 40% of the estimated erosion of the watershed within which they were situated. If all plantations achieved vegetation cover equivalent to the best 25% of plantations, the estimated erosion would be reduced by 7% in Costa Rica and 8% in Guatemala. If all plantations implemented soil conservation practices, estimated erosion would be reduced by 11% in Costa Rica and 35% in Guatemala. With the two combined management strategies a reduction of estimated erosion of 17% and 40% was predicted in Costa Rica and Guatemala, respectively. The reduction in erosion from soil conservation or better vegetative cover varied among regions within countries depending on current management, local climate, and topography. These results show the importance of coffee system and soil management practices in moderating erosion from highland coffee production, and how RUSLE analyses can identify priority practices in different regions supporting more effective policies to reduce soil erosion

Shade and agronomic intensification in coffee agroforestry systems: trade-off or synergy?

Despite many years of research, there is still a lack of consensus as to the nature of the relationship between shade trees and agronomic intensification in coffee agroforestry systems. While some studies find un-shaded intensively managed coffee is the most productive, other studies find no trade-off between shade characteristics and productivity. Our study of 179 farms from the main coffee growing regions of Costa Rica and Guatemala analysed how shade affected the productive response of coffee to intensification of agronomic management. Four levels of coffee productivity were differentiated for each country associated with three levels of shade development in Costa Rica and two levels in Guatemala. The highest coffee productivity group was associated with medium shade development in both countries. High shade groups had low productivity, but very low productivity groups were associated with low (Costa Rica) or medium (Guatemala) shade. Medium and high productivity farms were associated with high elevation, lower rainfall and regions with higher coffee prices. Yield with a moderate level of investment (720-1500 USD−1) and with medium shade (LAI 0.55-1.1) was not significantly different from yields with higher investment or lower shade levels. The increase in yield with increasing N fertilizer application was similar under low, medium and high LAI, but the mean productivity significantly lower with high LAI. Agronomic intensification to increase productivity is equally effective for low and medium shade systems (LAI <1.1); low productivity farms may have high shade or low shade but are mainly limited by low investment. Intensification of production is compatible with medium shade levels that should deliver broader ecosystem services but achieving this depends on coffee prices enabling this investment

Correction: The use of bluetooth low energy Beacon systems to estimate indirect personal exposure to household air pollution

An amendment to this paper has been published and can be accessed via a link at the top of the paper

LPG stove and fuel intervention among pregnant women reduce fine particle air pollution exposures in three countries: Pilot results from the HAPIN trial

The Household Air Pollution Intervention Network trial is a multi-country study on the effects of a liquefied petroleum gas (LPG) stove and fuel distribution intervention on women's and children's health. There is limited data on exposure reductions achieved by switching from solid to clean cooking fuels in rural settings across multiple countries. As formative research in 2017, we recruited pregnant women and characterized the impact of the intervention on personal exposures and kitchen levels of fine particulate matter (PM2.5) in Guatemala, India, and Rwanda. Forty pregnant women were enrolled in each site. We measured cooking area concentrations of and personal exposures to PM2.5 for 24 or 48 h using gravimetric-based PM2.5 samplers at baseline and two follow-ups over two months after delivery of an LPG cookstove and free fuel supply. Mixed models were used to estimate PM2.5 reductions. Median kitchen PM2.5 concentrations were 296 μg/m3 at baseline (interquartile range, IQR: 158-507), 24 μg/m3 at first follow-up (IQR: 18-37), and 23 μg/m3 at second follow-up (IQR: 14-37). Median personal exposures to PM2.5 were 134 μg/m3 at baseline (IQR: 71-224), 35 μg/m3 at first follow-up (IQR: 23-51), and 32 μg/m3 at second follow-up (IQR: 23-47). Overall, the LPG intervention was associated with a 92% (95% confidence interval (CI): 90-94%) reduction in kitchen PM2.5 concentrations and a 74% (95% CI: 70-79%) reduction in personal PM2.5 exposures. Results were similar for each site. CONCLUSIONS: The intervention was associated with substantial reductions in kitchen and personal PM2.5 overall and in all sites. Results suggest LPG interventions in these rural settings may lower exposures to the WHO annual interim target-1 of 35 μg/m3. The range of exposure contrasts falls on steep sections of estimated exposure-response curves for birthweight, blood pressure, and acute lower respiratory infections, implying potentially important health benefits when transitioning from solid fuels to LPG

The use of bluetooth low energy Beacon systems to estimate indirect personal exposure to household air pollution.

Household air pollution (HAP) generated from solid fuel combustion is a major health risk. Direct measurement of exposure to HAP is burdensome and challenging, particularly for children. In a pilot study of the Household Air Pollution Intervention Network (HAPIN) trial in rural Guatemala, we evaluated an indirect exposure assessment method that employs fixed continuous PM2.5 monitors, Bluetooth signal receivers in multiple microenvironments (kitchen, sleeping area and outdoor patio), and a wearable signal emitter to track an individual's time within those microenvironments. Over a four-month period, we measured microenvironmental locations and reconstructed indirect PM2.5 exposures for women and children during two 24-h periods before and two periods after a liquefied petroleum gas (LPG) stove and fuel intervention delivered to 20 households cooking with woodstoves. Women wore personal PM2.5 monitors to compare direct with indirect exposure measurements. Indirect exposure measurements had high correlation with direct measurements (n = 62, Spearman ρ = 0.83, PM2.5 concentration range: 5-528 µg/m3). Indirect exposure had better agreement with direct exposure measurements (bias: -17 µg/m3) than did kitchen area measurements (bias: -89 µg/m3). Our findings demonstrate that indirect exposure reconstruction is a feasible approach to estimate personal exposure when direct assessment is not possible

Replication Data for: LPG stove and fuel intervention among pregnant women reduce fine particle air pollution exposures in three countries: Pilot results from the HAPIN trial

Documentation for Liao/Kirby et al data and scripts: Scripts: 1. Figure_1.R contains R script to generate figure 1. 2. Table_3.R contains R script to generate table 3. 3. Table 4+SM_analysis.do contains Stata script for generating table 4 and sensitivity analysis results in supplemental matarials. 4. SM_figures_tables.R contains R script for generating table S1 and figure S1 in supplemental materials. Data: 1. ExpMod_KAP_v2.csv contains processed kitchen PM2.5 data with covariates, for main analysis 2. ExpMod_PEM_v2.csv contains processed personal PM2.5 data with covariates, for main analysis 3. Pilot_expousre_data_IN+GT+RW_all.csv contains PM2.5 data only, including PM2.5 duplicates, for sensitivity analysis. 4. Table_2.xlsx contains baseline covariates data, for table 2. 5. Data dictionary.xlsx contains data dictionary for all above 4 datasets. Folder: 1. data: contains all data (explained above). 2. Figure2_data_script: contains data and script for generating figure 2 only

A risk assessment tool for resumption of research activities during the COVID-19 pandemic for field trials in low resource settings.

RationaleThe spread of severe acute respiratory syndrome coronavirus-2 has suspended many non-COVID-19 related research activities. Where restarting research activities is permitted, investigators need to evaluate the risks and benefits of resuming data collection and adapt procedures to minimize risk.ObjectivesIn the context of the multicountry Household Air Pollution Intervention (HAPIN) trial conducted in rural, low-resource settings, we developed a framework to assess the risk of each trial activity and to guide protective measures. Our goal is to maximize the integrity of reseach aims while minimizing infection risk based on the latest scientific understanding of the virus.MethodsWe drew on a combination of expert consultations, risk assessment frameworks, institutional guidance and literature to develop our framework. We then systematically graded clinical, behavioral, laboratory and field environmental health research activities in four countries for both adult and child subjects using this framework. National and local government recommendations provided the minimum safety guidelines for our work.ResultsOur framework assesses risk based on staff proximity to the participant, exposure time between staff and participants, and potential viral aerosolization while performing the activity. For each activity, one of four risk levels, from minimal to unacceptable, is assigned and guidance on protective measures is provided. Those activities that can potentially aerosolize the virus are deemed the highest risk.ConclusionsBy applying a systematic, procedure-specific approach to risk assessment for each trial activity, we were able to protect our participants and research team and to uphold our ability to deliver on the research commitments we have made to our staff, participants, local communities, and funders. This framework can be tailored to other research studies conducted in similar settings during the current pandemic, as well as potential future outbreaks with similar transmission dynamics. The trial is registered with clinicaltrials.gov NCT02944682 on October 26. 2016

Designing a comprehensive behaviour change intervention to promote and monitor exclusive use of liquefied petroleum gas stoves for the Household Air Pollution Intervention Network (HAPIN) trial

Introduction Increasing use of cleaner fuels, such as liquefied petroleum gas (LPG), and abandonment of solid fuels is key to reducing household air pollution and realising potential health improvements in low-income countries. However, achieving exclusive LPG use in households unaccustomed to this type of fuel, used in combination with a new stove technology, requires substantial behaviour change. We conducted theory-grounded formative research to identify contextual factors influencing cooking fuel choice to guide the development of behavioural strategies for the Household Air Pollution Intervention Network (HAPIN) trial. The HAPIN trial will assess the impact of exclusive LPG use on air pollution exposure and health of pregnant women, older adult women, and infants under 1 year of age in Guatemala, India, Peru, and Rwanda.Methods Using the Capability, Opportunity, Motivation–Behaviour (COM–B) framework and Behaviour Change Wheel (BCW) to guide formative research, we conducted in-depth interviews, focus group discussions, observations, key informant interviews and pilot studies to identify key influencers of cooking behaviours in the four countries. We used these findings to develop behavioural strategies likely to achieve exclusive LPG use in the HAPIN trial.Results We identified nine potential influencers of exclusive LPG use, including perceived disadvantages of solid fuels, family preferences, cookware, traditional foods, non-food-related cooking, heating needs, LPG awareness, safety and cost and availability of fuel. Mapping formative findings onto the theoretical frameworks, behavioural strategies for achieving exclusive LPG use in each research site included free fuel deliveries, locally acceptable stoves and equipment, hands-on training and printed materials and videos emphasising relevant messages. In the HAPIN trial, we will monitor and reinforce exclusive LPG use through temperature data loggers, LPG fuel delivery tracking, in-home observations and behavioural reinforcement visits.Conclusion Our formative research and behavioural strategies can inform the development, implementation, monitoring and evaluation of theory-informed strategies to promote exclusive LPG use in future stove programmes and research studies.Trial registration number NCT02944682, Pre-results