Upstream watershed condition predicts rural children\u27s health across 35 developing countries

Diarrheal disease (DD) due to contaminated water is a major cause of child mortality globally. Forests and wetlands can provide ecosystem services that help maintain water quality. To understand the connections between land cover and childhood DD, we compiled a database of 293,362 children in 35 countries with information on health, socioeconomic factors, climate, and watershed condition. Using hierarchical models, here we find that higher upstream tree cover is associated with lower probability of DD downstream. This effect is significant for rural households but not for urban households, suggesting differing dependence on watershed conditions. In rural areas, the effect of a 30% increase in upstream tree cover is similar to the effect of improved sanitation, but smaller than the effect of improved water source, wealth or education. We conclude that maintaining natural capital within watersheds can be an important public health investment, especially for populations with low levels of built capital

Can nature deliver on the sustainable development goals?

The increasing availability of data and improved analytical techniques now enable better understanding of where environmental conditions and human health are tightly linked, and where investing in nature can deliver net benefits for people—especially with respect to the most vulnerable populations in developing countries. These advances bring more opportunities for interventions that can advance multiple SDGs at once. We have harmonised a suite of global datasets to explore the essential nexus of forests, poverty, and human health, an overlap of SDG numbers 1, 2, 3, 6, and 15. Our study combined demographic and health surveys for 297 112 children in 35 developing countries with data describing the local environmental conditions for each child (appendix).4 This allowed us to estimate the effect forests might have in supporting human health, while controlling for the influence of important socio-economic differences.4 We extended this work to look at how forests affect three childhood health concerns of global significance for the world's poorest people: stunting, anaemia, and diarrhoeal disease

Ecological Restoration at Scale

In the age of Biodiversity Hotspots, ecological restoration at a landscape scale often provides the only avenue to successfully achieving our conservation goals. However, the resources needed to protect endangered ecosystems are limited. Here, we add four incremental advances in our understanding of how restoration strategies can be scaled up to play a meaningful global role in biodiversity conservation without incurring prohibitive costs. We explore several questions related to large-scale tropical forest restoration, using Area de Conservacion Guanacaste (ACG), in Costa Rica as a case study. First, we ask how successful has the largely passive restoration strategy (centered on wildfire prevention) been for restoring ACG dry forest, and what factors underpin the variation in forest recovery? Second, can organic waste disposal be harnessed as a restoration strategy for tropical forests? Third, how does second-growth forest heterogeneity translate into differential occupancy of regenerating habitat by large terrestrial vertebrates? Finally, moving beyond tropical forests, we look at how a passive restoration approach could be deployed in a deep-water marine context, asking where it would be most effective. The results of these research projects paint a picture of major opportunities to achieve significant conservation gains without breaking the proverbial bank. When soil conditions are favorable, fire management in ACG has been sufficient deliver canopy closure in less than 30 years. Further, when environmental conditions are not conducive to forest recovery, application of low-cost organic wastes seems to offer a powerful tool for promoting passive forest recovery. We find that overall, the value of second-growth forest for terrestrial vertebrates is high, and all threatened and endangered terrestrial vertebrates in ACG utilize young forest. Dndangered Baird’s tapirs are more frequently encountered in second-growth forest habitat than old growth forest. These lessons on the high but variable value of passive forest restoration methods offers a guide of sorts for how policymakers could prioritize the passive restoration of other habitats. Turning this thinking to the high seas reveals that eliminating international fishing in just 25% of its extent would likely protect more than 50% of the high seas’ total productivity

Organic Wastes and Tropical Forest Restoration

In a recent publication, we documented the benefits of using agricultural waste (specifically, leftover orange peels from a commercial orange juice factory) to promote forest recovery at a site in Costa Rica. While we showed unambiguously positive impacts on soil conditions, forest biomass, and tree diversity, our ability to infer mechanisms behind this recovery was limited because the project was never replicated. It appears our work is one of only a handful of peer-reviewed studies testing the use of unprocessed agricultural waste as part of a tropical forest restoration initiative. We argue that regardless of the mechanism, there are first-principle reasons to expect that minimally processed (and thus low-cost) agricultural wastes could be utilized to accelerate tropical forest restoration in a variety of contexts, potentially creating a new class of biodiversity-friendly carbon offsets that may address previous concerns about linking tropical forestry to global carbon markets. We outline research initiatives that could lead to a richer understanding of when and where it is safe and effective to utilize agricultural and other wastes in tropical forest restoration endeavors

The spatial and temporal domains of modern ecology

To understand ecological phenomena, it is necessary to observe their behaviour across multiple spatial and temporal scales. Since this need was first highlighted in the 1980s, technology has opened previously inaccessible scales to observation. To help to determine whether there have been corresponding changes in the scales observed by modern ecologists, we analysed the resolution, extent, interval and duration of observations (excluding experiments) in 348 studies that have been published between 2004 and 2014. We found that observational scales were generally narrow, because ecologists still primarily use conventional field techniques. In the spatial domain, most observations had resolutions ≤1 m2 and extents ≤10,000 ha. In the temporal domain, most observations were either unreplicated or infrequently repeated (\u3e1 month interval) and ≤1 year in duration. Compared with studies conducted before 2004, observational durations and resolutions appear largely unchanged, but intervals have become finer and extents larger. We also found a large gulf between the scales at which phenomena are actually observed and the scales those observations ostensibly represent, raising concerns about observational comprehensiveness. Furthermore, most studies did not clearly report scale, suggesting that it remains a minor concern. Ecologists can better understand the scales represented by observations by incorporating autocorrelation measures, while journals can promote attentiveness to scale by implementing scale-reporting standards

Upstream watershed condition predicts rural children’s health across 35 developing countries

Diarrheal disease (DD) due to contaminated water is a major cause of child mortality globally. Forests and wetlands can provide ecosystem services that help maintain water quality. To understand the connections between land cover and childhood DD, we compiled a database of 293,362 children in 35 countries with information on health, socioeconomic factors, climate, and watershed condition. Using hierarchical models, here we find that higher upstream tree cover is associated with lower probability of DD downstream. This effect is significant for rural households but not for urban households, suggesting differing dependence on watershed conditions. In rural areas, the effect of a 30% increase in upstream tree cover is similar to the effect of improved sanitation, but smaller than the effect of improved water source, wealth or education. We conclude that maintaining natural capital within watersheds can be an important public health investment, especially for populations with low levels of built capital

Low-cost agricultural waste accelerates tropical forest regeneration - Costa Rica 2014

<div>This .zip file provides all the data and an R Markdown document (written to .html but the original .Rmd is also included) that recreates all of the analyses that went into our 2018 Restoration Ecology Paper entitled <i>Low-cost agricultural waste accelerates tropical forest regeneration</i>. The methods describing how data were collected are available within the paper itself. The data was collected in Guanacaste Province, Costa Rica, in the summer of 2014. </div