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Despite worldwide knowledge of the importance of the Galápagos archipelago, there is little comparative plot data from the forests in the dry regions. We examined patterns of woody plant (≥2.5cm diameter at breast height (DBH)) species richness and structure using Gentry’s transect method (0.1ha) on the three largest islands in the Galápagos. We identified the conservation status of woody plants within the dry forest region, assessed forest cover and change in the region, and compared field results to other tropical dry forests in the Pacific. Of the 22 species encountered (11 native, 11 endemic), there were no non-native species and only one threatened species. Isabela, Santa Cruz and San Cristóbal have similar overall levels of species, genera, family and liana richness per site, but significantly different tree species richness, density and tree height per transect. Geospatial databases identified 51 species (native 40%, endemic 60%) of woody plants (≥2.5cm DBH) within the dry forest region of the Galápagos and 13 species (10 from the genus Scalesia) on the IUCN Red List. There is an estimated 551.97km2 of dry forest in the Galápagos and there has been little change (<0.01%) in forest cover from 2000 to 2015. Dry forests of the Galápagos have similar levels of species richness to Hawaii and the Marquesas but contain lower densities, basal areas and tree heights than other dry forests in the Pacific. These dry forests appear to be the best preserved and protected tropical dry forest in the Pacific.

Analysis of the ranges of nearly 15,000 plant and vertebrate species in the Amazon basin reveals that, from 2001 to 2019, a majority were affected by fire. Drought and forest policy were the best predictors of fire outcomes.

The prolonged 2012–2016 California drought has raised many issues including concerns over reduced vegetation health. Drought impacts are complicated by geographical differences in hydroclimatic variability due to a climatic dipole influenced by the Pacific. Analysis of MODIS‐derived Normalized Difference Vegetation Index and self‐calibrated Palmer Drought Severity Index from 2000 to 2018 reveals differences in drought and vegetation responses in Northern versus Southern California (NorCal vs SoCal, see definition in section [Section 2. Remote Sensing, Vegetation, and Hydroclimatic Data]). The greatest declines in Normalized Difference Vegetation Index were focused in the SoCal, while NorCal appears not severely affected thus far. It appears that both the strength of drought and the sensitivity of the vegetation to drought are larger in SoCal. The exacerbated aridity in SoCal is a trend extending throughout the past and present century. The spatial differences in hydroclimatology and vegetation responses are important considerations for statewide climate change adaptation—with SoCal potentially facing greater challenges. In this study, we investigated California vegetation responses to the recent prolonged 2012–2016 drought, which was potentially the driest 4‐year span in the last 1,200 years. The overall vegetation of the state has been presumed to be severely affected. However, Normalized Difference Vegetation Index (NDVI) satellite data related to vegetation greenness show that the large‐scale drought impacts on observable vegetation health were principally focused in Southern California regions, where the vegetation communities experienced striking declines in greenness. By contrast, some areas of Northern California have demonstrated significant NDVI increase and this difference in NDVI trends is evident over the past 19 years. The distinct vegetation behavior in Northern and Southern California seems to be related to a climatic dipole in the western United States, which is influenced by the large‐scale ocean‐atmosphere interactions. Some climate models predict an extension of such a dipole with greater precipitation in Northern California and less in Southern California by the end of the 21st century. Increased water demand in the south could intensify statewide intersectoral and interregional water competition in the future. However, increasing drought damage to wildlands and their terrestrial ecosystems in the south will not be relieved by any type of traditional water reallocation and irrigation effort. NDVI has decreased in Southern California but increased in the north and the higher elevations of the Sierra NevadaA hydroclimatic dipole contributes to the differing drought intensities and vegetation responses of Northern and Southern CaliforniaClimate change will likely intensify the north‐south hydroclimatic contrast in California

ABSTRACTUnderstanding the Tibetan Plateau’s role in environmental change has gained increasing scientific attention in light of warming and changes in land management. We examine changes in greenness over the Tibetan Plateau using the Normalized Difference Vegetation Index (NDVI) from the Global Inventory Monitoring and Modeling Study (GIMMS3g) to identify significant changes over the entire plateau, six ecoregions, and protected areas based on a multiyear time series of July imagery from 1982 to 2015. We also test whether there have been changes in human populations in protected areas. There has been relatively little change in mean NDVI over the Tibetan Plateau or ecoregions, however, there were significant changes at the pixel level. There are sixty-nine protected areas on the Tibetan Plateau; sixty-two protected areas had no significant change in mean NDVI and seven protected areas experienced a significant increase in NDVI. There has been an increase in population within protected areas from 2000 to 2015; however, mean populations significantly increased in two protected areas and significantly decreased in four protected areas. Results suggest a slow greening of the Tibetan Plateau, ecoregions, and protected areas, with a more rapid greening in northern Tibet at the pixel level. Most protected areas are experiencing minor changes in NDVI independent of human population.

Ecosystems in Mediterranean climates are adapted to seasonal drought. Multiannual drought, however, may significantly affect Mediterranean ecosystems and, further, may affect their constituent communities in different ways with differences in responses emerging during severe drought and over the course of long‐term climate change. This study investigates the response to recent prolonged drought of two important Mediterranean‐climate vegetation types: chaparral and coastal sage scrub. Their greenness was monitored from 2000 to 2017 using the Normalized Difference Vegetation Index (NDVI) derived from the Moderate Resolution Imaging Spectroradiometer. A bootstrapped multiple regression of NDVI anomalies against Palmer Drought Severity Index was used to assess the response of vegetation to drought. The results suggest that drought had a greater effect on chaparral‐dominated ecosystems than coastal sage over the entire region. Shallow‐rooted coastal sage scrub displayed higher interannual variability in NDVI than chaparral but had a lower correlation with Palmer Drought Severity Index. This suggests that this vegetation community is generally less responsive to drought on longer timescales than chaparral, which may be more sensitive to soil water depletion in a prolonged drought. Soil texture plays a critical role in affecting the community sensitivity to drought. For chaparral communities, elevation is negatively correlated with drought sensitivity, suggesting the role of temperature‐related water stress on their long‐term response to drought. Future predicted climate change in the form of increased temperature and drought hazards in Southern California will influence the native ecosystems in nonuniform ways. Long‐term trends in soil moisture depletion and temperature may be particularly important in chaparral‐dominated areas. Chaparral and coastal sage scrub are the two most widely distributed shrubland communities along the South Pacific Coast of California. Shallow‐rooted coastal sage scrub has been presumed to be more vulnerable to drought, compared to the deep‐rooted chaparrals. However, the recent prolonged 2012–2016 drought, which has been reported as the worst drought in the last 1,200 years, suggests otherwise. Satellite data show that chaparral ecosystems have been more affected by drought than the coastal sage, indicating the higher vulnerability of chaparral over the long term. Chaparral plants are generally more dependent on water in deeper soil layers, making them more resistant to short‐term drought (e.g., <1 year) than coastal sage, but this physiological characteristic, at the same time, makes them susceptible to prolonged droughts (e.g., >2 years). Local response of both communities during drought are dependent upon soil texture, with sandier soils that have higher water holding capacity providing a greater buffer against drought impacts. Chaparral sensitivity to drought, in addition, depends upon elevation that, in turn, controls local temperature. Communities in lower, warmer sites displayed greater drought sensitivity compared to higher, cooler sites, implying that future climate warming may further exacerbate the impact of drought on chaparral ecosystems. Impacts of the recent prolonged California droughts on two native vegetation types, chaparral and coastal scrub, were investigatedA bootstrapped multiple regression suggests drought had a greater long‐term effect on chaparral‐dominated ecosystems than coastal sageSoil texture and elevation play critical roles in affecting the vegetation sensitivity to water stress

Biodiversity monitoring is an almost inconceivable challenge at the scale of the entire Earth. The current (and soon to be flown) generation of spaceborne and airborne optical sensors (i.e., imaging spectrometers) can collect detailed information at unprecedented spatial, temporal, and spectral resolutions. These new data streams are preceded by a revolution in modeling and analytics that can utilize the richness of these datasets to measure a wide range of plant traits, community composition, and ecosystem functions. At the heart of this framework for monitoring plant biodiversity is the idea of remotely identifying species by making use of the ‘spectral species’ concept. In theory, the spectral species concept can be defined as a species characterized by a unique spectral signature and thus remotely detectable within pixel units of a spectral image. In reality, depending on spatial resolution, pixels may contain several species which renders species‐specific assignment of spectral information more challenging. The aim of this paper is to review the spectral species concept and relate it to underlying ecological principles, while also discussing the complexities, challenges and opportunities to apply this concept given current and future scientific advances in remote sensing. Biodiversity monitoring based on field data is almost inconceivable at the scale of the entire Earth. Over the past decades, remote sensing has opened possibilities for Earth observation from air and space, allowing us to monitor ecological change, primarily expressed by changes in vegetation cover, distribution, and functioning, which can be subsequently linked to drivers of change in space and time, from local to global scale. Recently, the spectral species concept—an algorithm that clusterizes pixels from spectral images having a similar spectral signal (referred to as ‘spectral species’)—has brought attention. The aim of this paper is to review the ecological functioning principles of the spectral species concept and to refine its definition by a better linkage with field observations of plant species distribution data (i.e., presence‐absence data) available from vegetation surveys. Remote sensing has opened possibilities for Earth observation from air and space, allowing us to monitor ecological changeBiodiversity monitoring based on field data is almost inconceivable at the scale of the entire EarthThe spectral species concept, relating field to remotely sensed data, can open new ways to measure diversity from space Remote sensing has opened possibilities for Earth observation from air and space, allowing us to monitor ecological change Biodiversity monitoring based on field data is almost inconceivable at the scale of the entire Earth The spectral species concept, relating field to remotely sensed data, can open new ways to measure diversity from space

On 26 December 2004, a magnitude 9.2 earthquake off the west coast of the northern Sumatra, Indonesia, resulted in 160,000 Indonesians killed. We examine the Defense Meteorological Satellite Program-Operational Linescan System night-time light imagery brightness values for 307 communities in the Study of the Tsunami Aftermath and Recovery (STAR), a household survey in Sumatra from 2004 to 2008. We examined nightlight time series between the annual brightness and extent of damage, economic metrics collected from STAR households and aggregated to the community level. There were significant changes in brightness values from 2004 to 2008 with a significant drop in brightness values in 2005 due to the tsunami and pre-tsunami night-time light values returning in 2006 for all damage zones. There were significant relationships between the night-time imagery brightness and per capita expenditures, and spending on energy and on food. Results suggest that Defense Meteorological Satellite Program night-time light imagery can be used to capture the impacts and recovery from the tsunami and other natural disasters and estimate time series economic metrics at the community level in developing countries.

In the Hawaiian dry forest, 45% of all tropical dry forest trees and shrubs are on the federal threatened and endangered species list. Research is needed to understand the current range of these endangered species, the factors that affect their current and future distributions, and ultimately, identify areas where the most successful restoration can be undertaken. This research uses species distribution modelling to predict the potential range of Hibiscus brackenridgei, the state flower of Hawaii and a federally endangered species found on Oahu. We used presence data and the modelling algorithm Maxent to model the current potential distribution of H. brackenridgei, identify climate and environmental variables that influence the species’ distribution, and model the species’ predicted future distribution based on a range of projected climate change scenarios. Statistical analysis suggests that the Maxent models accurately predict the species’ distribution, and therefore, may be useful for conservation management. Comparing the current model with the future models of changes for 2060-2089, changes in the potential niche of H. brackenridgei only range by -4% to 14%. This suggests that the predicted changes in climate, under both low (B2a) and high (A2a) SRES (Special Report on Emissions Scenarios) global emissions scenarios, may not significantly impact the future distribution of H. brackenridgei on Oahu. We identified a total of 115 km2 of very highly (≥ 0.70) and highly (≥ 0.50) suitable habitat which represents potential areas where restoration projects could be implemented. This research suggests that threats like habitat loss, fire, invasive species, and grazing may be more important than climate for the future conservation of Hawaiian dry forest species.

The Hawaiian Islands hold a unique geographic position that has resulted in plant species with remarkable evolutionary adaptations to island life as well as the highest proportion of plant endemism (90%) in the world. Polynesians and Europeans significantly reduced the extent of native vegetation types, and Europeans introduced non‐native plants that have become highly invasive. The Hawaiian Islands have been extremely susceptible to invasion due to the fact that they are oceanic islands; they contain low intensities of competition; they have altered disturbance regimes; and a relatively short time has passed since non‐native plant introductions, suggesting that the situation can only get worse. African grasses, Leucaena leucocephala, Psidiumsp., Miconia calvescens, and Schinus terebinthifolius, are some of the most aggressive invasive plant species in the Hawaiian Islands. Species databases, remote sensing methods, and geographic information system analyses are currently being developed and will be extremely important for identifying the extent and threat of invasive plants. The three main methods of invasive plant removal include manual/mechanical removal, herbicide application, and biological controls. A number of federal, state, and non‐profit organizations are involved with the management of invasive plant species in the Hawaiian Islands. However, much more attention must be paid to protecting some of the most unique and endangered ecosystems on the planet.

We welcome to this issue which begins Volume XLI, Thomas W. Gillespie as Chairman of the Editorial Council of THEOLOGY TODAY. A Californian who has come East, Dr. Gillespie is the newly elected President of Princeton Theological Seminary and Professor of New Testament. He is a graduate of George Pepperdine College, Princeton Seminary, and the Claremont Graduate School, where he received the doctorate in New Testament studies. He has served as the minister of the Garden Grove and Burlingame Presbyterian Churches, and as Adjunct Professor at San Francisco and Fuller Seminaries and at New College Berkeley. In church affairs, Dr. Gillespie has been active in local and national committees on ecumenism and theological education.