Hawaiian tropical dry forests contain diverse assemblages of woody canopy species, including many endemic and endangered species that warrant conservation attention before completely disappearing. Today, tropical dry forests in Hawaii are not viable ecosystems. Poor land use practices, fragmentation, non-native plant invasions, and inadequate native vegetation regeneration are all factors that have contributed to their endangerment. Only an ambitious restoration programme that includes non-native ungulate exclusion, weed control, fire management, and the outplanting of seeds and seedlings will be sufficient to enhance Hawaiian tropical dry forests. We selected a 25 ha preserve within the Kaupulehu Dry Forest Preserve, located in North Kona on the Island of Hawaii, to test dry forest restoration strategies. In 1997, the preserve was fenced and all non-native ungulates were removed. Altogether, 4892 outplants were planted from 1999?2006. In 2007, we surveyed all of the outplants. The survey found 1487 live plants, 3357 dead, and 48 plants missing. This equates to an overall survival rate of 30%. Survival by vegetation type indicated that vines had the highest rate of survival (63%) followed by trees (34%). Herbs had the lowest rate of survival (12%). Twelve of a total of 35 species that were outplanted in the Kaupulehu Dry Forest Preserve accounted for more than 90% of the total surviving plants species, while five federally listed species represent almost 60% of the total. The outplanting of dry forest species into the Kaupulehu Dry Forest Preserve considerably increased the population of many federally listed endangered species. However, the high mortality of many common and important plant species of tropical dry systems highlights the importance of an outplanting programme that emphasizes ecosystem sustainability rather that species success. In equal measure, the successes and failures of the Kaupulehu outplanting project have enhanced our ability to begin to restore this unique and endangered ecosystem.

Secondary forests constitute a substantial proportion of tropical forestlands. These forests occur on both public and private lands and different underlying environmental variables and management regimes may affect post‐abandonment successional processes and resultant forest structure and biodiversity. We examined whether differences in ownership led to differences in forest structure, tree diversity, and tree species composition across a gradient of soil fertility and forest age. We collected soil samples and surveyed all trees in 82 public and 66 private 0.1‐ha forest plots arrayed across forest age and soil gradients in Guanacaste, Costa Rica. We found that soil fertility appeared to drive the spatial structure of public vs. private ownership; public conservation lands appeared to be non‐randomly located on areas of lower soil fertility. On private lands, areas of crops/pasture appeared to be non‐randomly located on higher soil fertility areas while forests occupied areas of lower soil fertility. We found that forest structure and tree species diversity did not differ significantly between public and private ownership. However, public and private forests differed in tree species composition: 11 percent were more prevalent in public forest and 7 percent were more prevalent in private forest. Swietenia macrophylla, Cedrela odorata, and Astronium graveolens were more prevalent in public forests likely because public forests provide stronger protection for these highly prized timber species. Guazuma ulmifolia was the most abundant tree in private forests likely because this species is widely consumed and dispersed by cattle. Furthermore, some compositional differences appear to result from soil fertility differences due to non‐random placement of public and private land holdings with respect to soil fertility. Land ownership creates a distinctive species composition signature that is likely the result of differences in soil fertility and management between the ownership types. Both biophysical and social variables should be considered to advance understanding of tropical secondary forest structure and biodiversity.

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This chapter asks whether environmental and human health are well served by the creation and use of simple indices, such as the California Communities Environmental Health Screening Tool and the Environmental Performance Index. Reducing vast complexity to a single number offers the possibility of helping to communicate complex science to the public and to decision-makers. Indices are appealing because they are quantitative, have the appearance of being data-based, and seem objective. However, the biases and potential errors inherent in simplifying multidimensional data can result in misleading or incorrect conclusions. This chapter details some problems inherent to environmental indices, examines how these issues have led wellintentioned studies astray, and offers solutions to navigate the indices landscape.

Computational skills are advantageous for teaching students to investigate environmental change using satellite remote sensing. This focus is especially relevant given the disproportionate underrepresentation of minorities and women in STEM fields. This study quantified the effects in both a STEM and a non-STEM class of Earth science remote sensing modules in Google Earth Engine on students’ self-efficacy in coding, understanding remote sensing, and interest in science and a career in environmental research. Additionally, the STEM students engaged in a course-based undergraduate research experience (CURE) on water quality. Satellite imagery was used to visualize water quality changes in coastal areas around the world due to the COVID-19 pandemic shutdown. Pre- and post-surveys reveal statistically significant changes in most students’ confidence to apply coding skills to investigate environmental change and understand remote sensing. The intervention was not sufficient to lead to significant changes in interest in science or a career in environmental research. There is great benefit in incorporating remote sensing labs to teach environmental concepts to STEM and non-STEM students and to bolster the confidence of underrepresented minorities and females in STEM.