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1.
Infant Behav Dev ; 76: 101958, 2024 May 20.
Article in English | MEDLINE | ID: mdl-38772284

ABSTRACT

Early vocabulary development is crucial for future cognitive and academic outcomes, and parent-child booksharing has been recognized as a powerful home literacy practice to promote word learning. However, evidence about the link between booksharing and language development in diverse cultural and socioeconomic settings is currently limited, hindering the formulation of a broadly applicable framework to understand the favorable conditions for early vocabulary development. This study explores the relationship between booksharing and early receptive and expressive vocabulary in a sample of 183 mothers and their toddlers in Costa Rica, a context where reading is not a common practice and children have limited access to books. Mothers completed an interview about their booksharing practices and reported children's receptive and expressive vocabulary. Results demonstrated a positive link between maternal booksharing and children's expressive vocabulary. Child gender moderated the link between booksharing and receptive vocabulary, exhibiting a stronger association in girls than in boys. Mothers with lower education levels reported higher expressive vocabulary scores for their children than mothers with higher education levels. These findings underscore the significance of booksharing in the home literacy environment, even in cultural contexts with distinct reading practices. Moreover, they highlight the need to incorporate sociocultural factors into comprehensive accounts concerning the role of booksharing in early word learning.

2.
Environ Resour Econ (Dordr) ; : 1-6, 2020 Jul 13.
Article in English | MEDLINE | ID: mdl-32836838

ABSTRACT

COVID-19 is currently having major short run effects with possible serious long run implications for the environment and the management of natural resources in Latin America. We discuss the possible effects of the pandemic on air pollution, deforestation and other relevant environmental dimensions across the region. With contributions from environmental economists from eight countries, we give an overview of the initial and expected environmental effects of this health crisis. We discuss potential effects on environmental regulations, possible policy interventions, and an agenda for future research for those interested in the design and evaluation of environmental policies relevant for the Latin American context.

3.
Proc Natl Acad Sci U S A ; 116(30): 14916-14925, 2019 07 23.
Article in English | MEDLINE | ID: mdl-31285315

ABSTRACT

Protected areas (PAs) are the leading tools to conserve forests. However, given their mixed effectiveness, we want to know when they have impacts internally and, if they do, when they have spillovers. Political economy posits roles for the level of government. One hypothesis is that federal PAs avoid more internal deforestation than state PAs since federal agencies consider gains for other jurisdictions. Such political differences as well as economic mechanisms can cause PA spillovers to vary greatly, even from "leakage," more deforestation elsewhere, to "blockage," less deforestation elsewhere. We examine internal impacts and local spillovers for Brazilian Amazon federal and state agencies. Outside the region's "arc of deforestation," we confirm little internal impact and show no spillovers. In the "arc," we test impacts by state, as states are large and feature considerably different dynamics. For internal impacts, estimates for federal PAs and indigenous lands are higher than for state PAs. For local spillover impacts, estimates for most arc states either are not significant or are not robust; however, for Pará, federal PAs and indigenous lands feature both internal impacts and local spillovers. Yet, the spillovers in Pará go in opposite directions across agencies, leakage for indigenous lands but blockage for federal PAs, suggesting a stronger external signal from the environmental agency. Across all these tools, only federal PAs lower deforestation internally and nearby. Results suggest that agencies' objectives and capacities are critical parts of the contexts for conservation strategies.


Subject(s)
Conservation of Natural Resources/legislation & jurisprudence , Environmental Policy , Government Agencies/standards , Brazil , Conservation of Natural Resources/statistics & numerical data
4.
PLoS One ; 13(10): e0205964, 2018.
Article in English | MEDLINE | ID: mdl-30335845

ABSTRACT

Protected areas (PAs) are a prominent approach to maintaining and enhancing biodiversity and ecosystem services. A critical question for safeguarding these resources is how PA governance processes and management structures influence their effectiveness. We conduct an impact evaluation of 12 PAs in three Central American countries to assess how processes in management restrictions, management capacity, and decentralization affect the annual change in the satellite-derived Normalized Difference Vegetation Index (NDVI). NDVI varies with greenness that relates to plant production, biomass, and important ecosystem functions related to biodiversity and ecosystem services such as water quality and carbon storage. Any loss of vegetation cover in the form of deforestation or degradation would show up as a decrease in NDVI values over time and gains in vegetation cover and regeneration as an increase in NDVI values. Management restriction categories are based on international classifications of strict versus multiple-use PAs, and capacity and decentralization categories are based on key informant interviews of PA managers. We use matching to create a counterfactual of non-protected observations and a matching estimator and regression to estimate treatment effects of each sub-sample. On average, strict and multiple-use PAs have a significant and positive effect on NDVI compared to non-protected land uses. Both high and low decentralized PAs also positively affect NDVI. High capacity PAs have a positive and significant effect on NDVI, while low capacity PAs have a negative effect on NDVI. Our findings advance knowledge on how governance and management influence PA effectiveness and suggest that capacity may be more important than governance type or management restrictions in maintaining and enhancing NDVI. This paper also provides a guide for future studies to incorporate measures of PA governance and management into impact evaluations.


Subject(s)
Conservation of Natural Resources , Ecosystem , Central America , Confidence Intervals , Geography , Plants
5.
PLoS One ; 13(9): e0203545, 2018.
Article in English | MEDLINE | ID: mdl-30212511

ABSTRACT

In order to ensure the provision of goods and services from forests, many governments have promoted less-traditional conservation initiatives such as programs of payments for ecosystem services called, more broadly, direct payments for conservation. The Socio Bosque Program (SBP) is a governmental program in Ecuador that directly provides economic incentives to rural families and local and indigenous communities who have voluntarily agreed to comply with some conservation activities. An impact evaluation method (matching) was used to assess the impact of the SBP between 2008 and 2014. This study revealed that on average, the SBP reduced deforestation by 1.5% in those forests that received the SBP's direct payment. These forests would have been deforested if the SBP had not been implemented. Assessment of the impact of the SBP on individual and collective contracts, using the matching method, revealed that 3.4% and roughly 1% of the forest would have been deforested in the absence of the program, respectively. In other words, the protected area in the collective SBP was 1,247,500 ha and, if the SBP had not been implemented, an area of 11,227 ha would have been lost between 2008 and 2014. The 165,700 ha protected by the individual SBP, it was estimated that 5,733 ha were not deforested due to the implementation of the conservation program. Conventional estimates of the impact of the SBP tend to overestimate avoided deforestation because they do not control for observable covariates that correlate with or affect both SBP participation and deforestation. The conclusions are robust, even given potential hidden biases. The present study demonstrated that the SBP serves to mitigate the effects of climate change, especially with those contracts that are intended for individual owners.


Subject(s)
Conservation of Natural Resources , Forests , Ecosystem , Government
6.
PLoS One ; 13(7): e0189360, 2018.
Article in English | MEDLINE | ID: mdl-30001357

ABSTRACT

Previous research on adolescent cigarette adoption has focused on peer influence and the perceived status gain from smoking but has ignored the status effects on peer influence. We analyze adolescent peer effects on cigarette consumption while considering the popularity of peers. The analysis is based on a four wave panel survey representative of American high school students. We measure peers' popularity by their eigenvector centrality in high school social networks. Using lagged peers' behavior, school fixed effects, and instrumental variables to control for homophily and contextual confounds, we find that the probability of smoking the following year increases with the mean popularity of smokers, while the popularity of non-smokers has the opposite effect. These effects persist seven and fourteen years later (wave 3 and 4 of the data). In addition, the probability of smoking increases with the smoking propensity of the 20% most popular teens and decreases with the smoking propensity of the bottom 80%. The results indicate the importance of knowing not only the smoking propensity within a school but also the location of smokers within the social hierarchy.


Subject(s)
Adolescent Behavior/psychology , Imitative Behavior , Peer Influence , Smoking/psychology , Students/psychology , Adolescent , Female , Hierarchy, Social , Humans , Male , Peer Group , Schools , Social Networking , Surveys and Questionnaires
7.
Philos Trans R Soc Lond B Biol Sci ; 370(1681)2015 Nov 05.
Article in English | MEDLINE | ID: mdl-26460126

ABSTRACT

The leading policy to conserve forest is protected areas (PAs). Yet, PAs are not a single tool: land users and uses vary by PA type; and public PA strategies vary in the extent of each type and in the determinants of impact for each type, i.e. siting and internal deforestation. Further, across regions and time, strategies respond to pressures (deforestation and political). We estimate deforestation impacts of PA types for a critical frontier, the Brazilian Amazon. We separate regions and time periods that differ in their deforestation and political pressures and document considerable variation in PA strategies across regions, time periods and types. The siting of PAs varies across regions. For example, all else being equal, PAs in the arc of deforestation are relatively far from non-forest, while in other states they are relatively near. Internal deforestation varies across time periods, e.g. it is more similar across the PA types for PAs after 2000. By contrast, after 2000, PA extent is less similar across PA types with little non-indigenous area created inside the arc. PA strategies generate a range of impacts for PA types--always far higher within the arc--but not a consistent ranking of PA types by impact.


Subject(s)
Conservation of Natural Resources/methods , Forests , Brazil , Ecosystem , Forestry , Politics , Public Policy
8.
PLoS One ; 10(7): e0129460, 2015.
Article in English | MEDLINE | ID: mdl-26225922

ABSTRACT

Protected areas are the leading forest conservation policy for species and ecoservices goals and they may feature in climate policy if countries with tropical forest rely on familiar tools. For Brazil's Legal Amazon, we estimate the average impact of protection upon deforestation and show how protected areas' forest impacts vary significantly with development pressure. We use matching, i.e., comparisons that are apples-to-apples in observed land characteristics, to address the fact that protected areas (PAs) tend to be located on lands facing less pressure. Correcting for that location bias lowers our estimates of PAs' forest impacts by roughly half. Further, it reveals significant variation in PA impacts along development-related dimensions: for example, the PAs that are closer to roads and the PAs closer to cities have higher impact. Planners have multiple conservation and development goals, and are constrained by cost, yet still conservation planning should reflect what our results imply about future impacts of PAs.


Subject(s)
Conservation of Natural Resources/methods , Forestry/methods , Social Planning , Brazil , Cities , Ecosystem , Forests , Social Change
9.
PLoS One ; 10(4): e0124910, 2015.
Article in English | MEDLINE | ID: mdl-25909323

ABSTRACT

We estimate the effects on deforestation that have resulted from policy interactions between parks and payments and between park buffers and payments in Costa Rica between 2000 and 2005. We show that the characteristics of the areas where protected and unprotected lands are located differ significantly. Additionally, we find that land characteristics of each of the policies and of the places where they interact also differ significantly. To adequately estimate the effects of the policies and their interactions, we use matching methods. Matching is implemented not only to define adequate control groups, as in previous research, but also to define those groups of locations under the influence of policies that are comparable to each other. We find that it is more effective to locate parks and payments away from each other, rather than in the same location or near each other. The high levels of enforcement inside both parks and lands with payments, and the presence of conservation spillovers that reduce deforestation near parks, significantly reduce the potential impact of combining these two policies.


Subject(s)
Conservation of Natural Resources/legislation & jurisprudence , Forests , Conservation of Natural Resources/economics , Conservation of Natural Resources/methods , Costa Rica , Ecosystem , Geography , Humans
10.
Proc Natl Acad Sci U S A ; 105(42): 16089-94, 2008 Oct 21.
Article in English | MEDLINE | ID: mdl-18854414

ABSTRACT

Global efforts to reduce tropical deforestation rely heavily on the establishment of protected areas. Measuring the effectiveness of these areas is difficult because the amount of deforestation that would have occurred in the absence of legal protection cannot be directly observed. Conventional methods of evaluating the effectiveness of protected areas can be biased because protection is not randomly assigned and because protection can induce deforestation spillovers (displacement) to neighboring forests. We demonstrate that estimates of effectiveness can be substantially improved by controlling for biases along dimensions that are observable, measuring spatial spillovers, and testing the sensitivity of estimates to potential hidden biases. We apply matching methods to evaluate the impact on deforestation of Costa Rica's renowned protected-area system between 1960 and 1997. We find that protection reduced deforestation: approximately 10% of the protected forests would have been deforested had they not been protected. Conventional approaches to evaluating conservation impact, which fail to control for observable covariates correlated with both protection and deforestation, substantially overestimate avoided deforestation (by over 65%, based on our estimates). We also find that deforestation spillovers from protected to unprotected forests are negligible. Our conclusions are robust to potential hidden bias, as well as to changes in modeling assumptions. Our results show that, with appropriate empirical methods, conservation scientists and policy makers can better understand the relationships between human and natural systems and can use this to guide their attempts to protect critical ecosystem services.


Subject(s)
Conservation of Natural Resources , Sensitivity and Specificity , Time Factors
11.
Conserv Biol ; 21(5): 1165-73, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17883482

ABSTRACT

We evaluated the intention, implementation, and impact of Costa Rica's program of payments for environmental services (PSA), which was established in the late 1990s. Payments are given to private landowners who own land in forest areas in recognition of the ecosystem services their land provides. To characterize the distribution of PSA in Costa Rica, we combined remote sensing with geographic information system databases and then used econometrics to explore the impacts of payments on deforestation. Payments were distributed broadly across ecological and socioeconomic gradients, but the 1997-2000 deforestation rate was not significantly lower in areas that received payments. Other successful Costa Rican conservation policies, including those prior to the PSA program, may explain the current reduction in deforestation rates. The PSA program is a major advance in the global institutionalization of ecosystem investments because few, if any, other countries have such a conservation history and because much can be learned from Costa Rica's experiences.


Subject(s)
Conservation of Natural Resources/economics , Ecosystem , Conservation of Natural Resources/methods , Costa Rica , Forestry , Ownership/economics , Public Policy , Time Factors
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