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Haiti’s groundwater resources are poorly understood and scarcely researched, despite their importance as the principal source for water supply. The knowledge gap and its role of inhibiting informed relief, recovery and investments in development are described, along with an update on progress towards the UN Sustainable Development Goals. This essay leads a topical collection of seven articles that advance hydrogeological knowledge of Haiti. Additional data, research and monitoring are identified as urgently needed for the nation’s sustainable development.

Mountain block recharge (MBR) mechanisms are an important component of the water budget for many alluvial aquifers worldwide. The MBR dynamics are complex, difficult to constrain, and quantification is highly uncertain. These challenges are magnified in data-scarce study areas, including the Cul-de-Sac and Leogane plains, two of Haiti’s largest alluvial aquifers, which are flanked by the Massif de la Selle mountain block. The associated groundwater supplies the regional metropolitan area of Port-au-Prince (RMPP) and it is facing increasing pressure, requiring improved understanding of the aquifer system to guide management and protection. This report introduces the aquifers and investigates the significance of river infiltration from flows originating from the mountain block. The approach to derive important insight on recharge included analysis of broad datasets on piezometry, isotopes, hydrochemistry, and streamflow. The findings indicate that river infiltration is a major source of recharge to the alluvial aquifers. Grise and Blanche river infiltration may account for >80% of recharge to the Cul-de-Sac aquifer, exhibiting temporal variation correlated to climate events such as cycles of the El Niño/La Niña Southern Oscillations. Momance and Rouyone river infiltration may account for >50% of recharge to the Leogane aquifer. The results direct attention to the Massif de la Selle carbonate aquifer system, where bulk recharge is estimated to be four times greater than both alluvial aquifers. The Massif not only supplies the RMPP with ~65% of its water supply from karst springs, but its streamflow also recharges the alluvial aquifers that supply the balance of RMPP supply.

A reconnaissance was performed for Tunnel Diquini and Source Mariani in the metropolitan region of Port-au-Prince, Haiti, to address concerns of decreasing flows and to evaluate potential impacts of a proposed river diversion scheme in the study area. The tunnel and spring are the two largest water sources serving the Port-au-Prince municipal water system and discharge from the Massif de la Selle carbonate aquifer. Considering their significance and importance to the water security of the region, there are limited data or studies specific to the water sources. An introductory framework was established regarding the flow regimes, the origin of waters, and recharge dynamics of the sources. Field reconnaissance and stable-isotope, tracer, and chloride-mass-balance techniques were applied to strengthen the conceptual understanding of the water sources. Recharge to this portion of the Massif de la Selle carbonate aquifer is variable depending on monthly rainfall intensity and 3–7-year climatic cycles. Rather than a consistent long-term decreasing flow trend, a particularly intense period from 2007 through 2010 resulted in the highest flows on record, which have steadily recessed to historical norms in recent years. The recharge characteristics and catchment areas indicate that neither water source is connected to the River Momance; however, a connection to the River Froide is possible, particularly related to the tunnel. Finally, recharge rates and an estimate of renewable groundwater in the Massif de la Selle show the regional significance and importance of the carbonate aquifer for current supplies and future water development.

A geophysical reconnaissance was conducted to support aquifer characterization and evaluate groundwater potential in the western portion of the Plaine du Nord aquifer to provision the growing water demands of the city of Cap-Haitien in the Republic of Haiti. Hybrid-source audio-magnetotelluric (HSAMT) soundings and gravity measurements were collected to support the Government of Haiti in sourcing additional water supplies for the city. The Plaine du Nord aquifer is poorly characterized considering it is one of Haiti’s largest aquifers, few drilling logs are available, and only one borehole has investigated the deeper extents of the aquifer. HSAMT supports depth profiling of subsurface resistivity, which supports interpretations of geological strata and groundwater conditions. Gravity measurements allow for complementary mapping of Earth density anomalies and contrasts, which assist in interpreting aquifer thicknesses or depth to bedrock. Pairing HSAMT and gravity methods permitted both an estimation of aquifer thickness and relative changes in sediment characteristics. Gravity results allowed for the mapping of aquifer thickness across the study area, with interpreted thickness greater than 300 m in the coastal zone. HSAMT results cross correlated with available well records and enabled the delineation of zones with increased groundwater potential. The results of the combined methods indicate groundwater storage potential of freshwater in deeper alluvium and emphasize the importance of strengthening resource characterization, modelling and monitoring to guide sustainable resource development and management.

The Plaine des Gonaïves houses a regionally significant yet data-scarce coastal aquifer in one of the driest regions of Haiti. It is the primary source of water for the region, including Haiti’s third largest city, Gonaïves. Pressure on groundwater resources will be compounded as municipal water services modernize and energy infrastructure enables the resurgence of commercial agriculture. In anticipation of increased stress and greater impacts, this study was undertaken (including data discovery, reconnaissance, and analysis) to gain insights and to advance understanding of the groundwater resources. The alluvial aquifer covers >115 km2, exceeds 100 m thickness, and supports pumping yields as high as 532 m3/h. The heterogeneous multilayer aquifer exhibits hydraulic conductivities that range by an order of magnitude, influencing groundwater flow, residence times, and chemistry. Significant recharge occurs in the central and upgradient portions of the plain; river infiltration appears to be a more significant recharge source than direct infiltration. In the downgradient portion of the plain, confined aquifer pressure increases and discharge areas include the Quinte River, springs, wetlands, ditches and canals. Underlying the alluvium, discontinuous groundwater in bedrock with structural influence may mix with the alluvial aquifer, affecting isotopic composition and water chemistry. Increased abstraction, climate change, and intensification of agriculture and urban development could have consequential impacts on water quantity, water quality and ecosystems. The results, insights, and supporting datasets are a baseline to guide planning and to advance a hydrogeological conceptual model that supports sustainable and informed groundwater management.

Isotope hydrological studies carried out since 1987 in Haiti have proven to be effective in improving conceptual models of the principal aquifers in this Caribbean island nation. However, many of these studies have been limited and are mostly unpublished. It is, therefore, important to share the available datasets with scientists and water managers to support further studies and guide decision-making. Eleven datasets were compiled in a unique database for continued advancement and application. This dataset now contains 248 δ18O and δ2H results from water samples collected at 190 locations throughout the country. δ18O and δ2H values range, respectively, from –3.8 to –8.95‰ and –67.4 to –16.8‰ for precipitation (n = 5), 0.9 to 2.76‰ and 8.8 to 18.4‰ for lakes (n = 4), –2.61 to 4.98‰ and –26.63 to 28.2‰ for rivers (n = 11), –5.11 to –2.6‰ and –29.8 to –6.9‰ for springs (n = 82) excluding hot springs, and –5.1 to –1.37‰ and –29.4 to –2.9‰ for boreholes (n = 142). The overall presentation of the available data is complemented with an overview of the studies in which stable isotope data acquisition was performed. The global dataset is presented under three primary contexts: (1) elaboration of a local isotope meteoric water line of equation δ2H = 7.2δ18O + 8.8 supported with data predominately from the Ouest jurisdictional department, (2) spatial variability analysis of the dataset, and (3) definition of the altitude gradient (per 100 m) using freshwater springs of the Plaine du Cul-de-Sac/Massif de la Selle area of –6.67‰ for δ2H and –0.09‰ for δ18O.

There are sparse hydrogeological data and insufficient hydrogeological knowledge in many areas of the world reliant on groundwater. Nicaragua’s Pacific coast is one such region that is also experiencing water scarcity resulting from increasing demand on groundwater resources and climate change. The primary source of water in the region is the aquifer system associated with the Brito Formation, which is a marine sedimentary stratum of mostly sandstone that blankets 75 km of coastline in southwest Nicaragua. This study focused on the Tola municipality with the objective to advance a conceptual understanding of the hydrogeology and to support sustainable water development. Results demonstrate a heterogeneous aquifer system with regional flow characteristics and other factors that influence groundwater availability and water quality. Primary porosity is low, and secondary porosity is the primary mechanism of aquifer storage and is influenced by geological structure and diagenesis processes. Groundwater recharge is spatially and temporally heterogeneous and direct recharge is low. Infiltration of streamflow and runoff, especially early in the rainy season, is thought to be a large component of groundwater recharge. Climate, flow and recharge dynamics, and low storage capacity make the Brito Formation a sensitive resource and vulnerable to drought, increased abstraction, and climate change. This assessment provides data and insights useful for informing future studies and investments within the region and may be applicable in other Central American and Caribbean nations with coastal sandstone aquifers.

European forests are threatened by increasing numbers of invasive pests and pathogens. Over the past century, Lecanosticta acicola, a foliar pathogen predominantly of Pinus spp., has expanded its range globally, and is increasing in impact. Lecanosticta acicola causes brown spot needle blight, resulting in premature defoliation, reduced growth, and mortality in some hosts. Originating from southern regions of North American, it devastated forests in the USA's southern states in the early twentieth century, and in 1942 was discovered in Spain. Derived from Euphresco project ‘Brownspotrisk,’ this study aimed to establish the current distribution of Lecanosticta species, and assess the risks of L. acicola to European forests. Pathogen reports from the literature, and new/ unpublished survey data were combined into an open-access geo-database (http://www.portalofforestpathology.com), and used to visualise the pathogen's range, infer its climatic tolerance, and update its host range. Lecanosticta species have now been recorded in 44 countries, mostly in the northern hemisphere. The type species, L. acicola, has increased its range in recent years, and is present in 24 out of the 26 European countries where data were available. Other species of Lecanosticta are largely restricted to Mexico and Central America, and recently Colombia. The geo-database records demonstrate that L. acicola tolerates a wide range of climates across the northern hemisphere, and indicate its potential to colonise Pinus spp. forests across large swathes of the Europe. Preliminary analyses suggest L. acicola could affect 62% of global Pinus species area by the end of this century, under climate change predictions. Although its host range appears slightly narrower than the similar Dothistroma species, Lecanosticta species were recorded on 70 host taxa, mostly Pinus spp., but including, Cedrus and Picea spp. Twenty-three, including species of critical ecological, environmental and economic significance in Europe, are highly susceptible to L. acicola, suffering heavy defoliation and sometimes mortality. Variation in apparent susceptibility between reports could reflect variation between regions in the hosts’ genetic make-up, but could also reflect the significant variation in L. acicola populations and lineages found across Europe. This study served to highlight significant gaps in our understanding of the pathogen's behaviour. Lecanosticta acicola has recently been downgraded from an A1 quarantine pest to a regulated non quarantine pathogen, and is now widely distributed across Europe. With a need to consider disease management, this study also explored global BSNB strategies, and used Case Studies to summarise the tactics employed to date in Europe.

The Murray River is Australia’s economically most important river system. As a result of its economic importance, land use change and river regulation have resulted in ecological degradation of the river and associated river wetlands (known throughout Australia as “billabongs”). Palaeolimnology can provide otherwise unobtainable information about the relative impacts of stressors and identify “refuges” from such impacts. We examine an approximately 1800 year history of water quality and vegetation at Junction Park Billabong, on the Murray River approximately 25 km upstream of the Murrumbidgee River confluence. Throughout this period the billabong has maintained a strong connection to the Murray River. Planktonic Aulacoseira granulata has been the dominant diatom in the Murray River, while surrounding vegetation has been dominated by open eucalpyt woodland. Around 500 years before present (BP), there was an increase in effective rainfall as indicated by a decline in Chenopodioideae (Amaranthaceae: saltbush) and an increase in Callitris (native pine) pollen. At the same time, there was an expansion in wetland submerged aquatic macrophytes, as evidenced through increases in the relative abundance of the epiphytic diatom, Cocconeis placentula and sediment organic matter. European settlement resulted in declines in aquatic macrophytes and nutrient enrichment but minimal increases in diatom-inferred salinity. There was relatively little post-settlement change in both the diatom stratigraphy and inferred water quality from Junction Park Billabong which contrasts somewhat with that observed in floodplain water bodies both upstream and downstream of Junction Park. The record from Junction Park Billabong highlights the sensitivity of floodplain wetlands to climate change and suggests that examination of these records can provide insights into late Holocene climate from a region where few high-resolution records from other sources exist.

The Greenland Ice Sheet (GrIS) is a key component of the global climate system. However, our current understanding of the spatio-temporal oscillations and landscape transformation of the GrIS margins since the last glacial cycle is still incomplete. The objective of this work is to study the deglaciation of the Zackenberg Valley (74°N, 20°E), NE Greenland, and the origin of the derived landforms. Based on extensive fieldwork and high-detail geomorphological mapping we identified the different types of landforms, from which those of glacial and paraglacial origin were used to understand the processes driving regional environmental evolution. We applied cosmic-ray exposure (CRE) dating to 32 samples taken from erosive and depositional glacial landforms distributed across the valley. Geomorphological evidence shows that >800-m-thick Late Quaternary glacier filled the valleys and fjords and covered mountain summits. In subsequent phases, as ice thickness decreased, the glacier was limited to the interior of the valley, leaving several lateral moraines. The deglaciation of the Zackenberg Valley that started by ~13.7–12.5 ka also accelerated slope paraglacial processes. Many blocks from lateral moraines were remobilized and fell, reaching the valley floor where they covered the thinning glacier tongue; transforming it into a debris-covered glacier that subsequently melted gradually. By ca. 10.5 ka, the last remnants of glacial ice disappeared from the Zackenberg Valley floor, a chronology of deglaciation that is similar to that observed in other sites across NE Greenland. The results of this work must be considered in similar studies, reinforcing the need to support CRE ages of the different geomorphological phases with paleoclimatic data from other sedimentary records.

Acute water security vulnerability at regional to local scales is becoming increasingly apparent. In 2017, officials in Cape Town, South Africa, designated the term “Day Zero” to demark an exact time when the city’s taps would be switched off due to critically low reservoir levels. Beyond Day Zero, residents would need to converge at communal water collection points to access a 25-L daily ration of water. The particulars of the crisis and stakeholder responses prove informative to other cities.

Background: Patients achieving a pathologic complete response (pCR) following neoadjuvant therapy have significantly improved event-free survival relative to those who do not; and pCR is an FDA-accepted endpoint to support accelerated approval of novel agents/combinations in the neoadjuvant treatment of high risk early stage breast cancer. Previous studies have shown that recurrence risk increased with increasing burden of residual disease (as assessed by the RCB index). As well, these studies suggest that patients with minimum residual disease (RCB-I class) also have favorable outcomes (comparable to those achieving a pCR) within high risk tumor subtypes. In this study, we assess whether integrating RCB with MRI functional tumor volume (FTV), which in itself is prognostic, can improve prediction of distant recurrence free survival (DRFS); and identify a subset of patients with minimal residual disease with comparable DRFS as those who achieved a pCR. Imaging tools can then be used to identify the subset that will do well early and guide the timing of surgical therapy. Method: We performed a pooled analysis of 596 patients from the I-SPY2 TRIAL with RCB, pre-surgical MRI FTV data and known follow-up (median 2.5 years). We first assessed whether FTV predicts residual disease (pCR or pCR/RCB-I) using ROC analysis. We applied a power transformation to normalize the pre-surgical FTV distribution; and assessed its association with DRFS using a bi-variate Cox proportional hazard model adjusting for HR/HER2 subtype. We also fitted a bivariate Cox model of RCB index adjusting for subtype; and assessed whether adding pre-surgical FTV to this model further improves association with DRFS using a likelihood ratio (LR) test. For the Cox modeling, penalized splines approximation of the transformed FTV and RCB index with 2 degrees of freedom was used to allow for non-linear effects of FTV and RCB on DRFS. Result: Pre-surgical MRI FTV is significantly associated with DRFS (Wald p Conclusion: Pre-surgical MRI FTV is effective at predicting minimal residual disease (RCB0/I) in the I-SPY 2 TRIAL. Despite the association between FTV and RCB, FTV appears to provide independent added prognostic value (to RCB and subtype), suggesting that integrating MRI volume measures and RCB into a composite predictor may improve DRFS prediction. Citation Format: Hylton NM, Symmans WF, Yau C, Li W, Hatzis C, Isaacs C, Albain KS, Chen Y-Y, Krings G, Wei S, Harada S, Datnow B, Fadare O, Klein M, Pambuccian S, Chen B, Adamson K, Sams S, Mhawech-Fauceglia P, Magliocco A, Feldman M, Rendi M, Sattar H, Zeck J, Ocal I, Tawfik O, Grasso LeBeau L, Sahoo S, Vinh T, Yang S, Adams A, Chien AJ, Ferero-Torres A, Stringer-Reasor E, Wallace A, Boughey JC, Ellis ED, Elias AD, Lang JE, Lu J, Han HS, Clark AS, Korde L, Nanda R, Northfelt DW, Khan QJ, Viscusi RK, Euhus DM, Edmiston KK, Chui SY, Kemmer K, Wood WC, Park JW, Liu MC, Olopade O, Tripathy D, Moulder SL, Rugo HS, Schwab R, Lo S, Helsten T, Beckwith H, Haugen PK, van't Veer LJ, Perlmutter J, Melisko ME, Wilson A, Peterson G, Asare AL, Buxton MB, Paoloni M, Clennell JL, Hirst GL, Singhrao R, Steeg K, Matthews JB, Sanil A, Berry SM, Abe H, Wolverton D, Crane EP, Ward KA, Nelson M, Niell BL, Oh K, Brandt KR, Bang DH, Ojeda-Fournier H, Eghtedari M, Sheth PA, Bernreuter WK, Umphrey H, Rosen MA, Dogan B, Yang W, Joe B, I-SPY 2 TRIAL Consortium, Yee D, Pusztai L, DeMichele A, Asare SM, Berry DA, Esserman LJ. Refining neoadjuvant predictors of three year distant metastasis free survival: Integrating volume change as measured by MRI with residual cancer burden [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-07-03.

Steady-state photosynthetic CO2 responses (A/Ci curves) are used to assess environmental responses of photosynthetic traits and to predict future vegetative carbon uptake through modeling. The recent development of rapid A/Ci curves (RACiRs) permits faster assessment of these traits by continuously changing [CO2 ] around the leaf, and may reveal additional photosynthetic properties beyond what is practical or possible with steady-state methods. Gas exchange necessarily incorporates photosynthesis and (photo)respiration. Each process was expected to respond on different timescales due to differences in metabolite compartmentation, biochemistry and diffusive pathways. We hypothesized that metabolic lags in photorespiration relative to photosynthesis/respiration and CO2 diffusional limitations can be detected by varying the rate of change in [CO2 ] during RACiR assays. We tested these hypotheses through modeling and experiments at ambient and 2% oxygen. Our data show that photorespiratory delays cause offsets in predicted CO2 compensation points that are dependent on the rate of change in [CO2 ]. Diffusional limitations may reduce the rate of change in chloroplastic [CO2 ], causing a reduction in apparent RACiR slopes under high CO2 ramp rates. Multirate RACiRs may prove useful in assessing diffusional limitations to gas exchange and photorespiratory rates.

Groundwater is increasingly viewed as a strategic resource to strengthen water security amidst climate change and growing demand from various sectors. Globally, urban centers face mounting challenges to balance supply with demand. Following the “Day Zero” water crisis in Cape Town (South Africa), city managers are acutely aware of the need to diversify water provisioning sources. In this chapter, we describe the Day Zero crisis, related climate drivers, and subsequent need to augment Cape Town’s surface water supply with groundwater. We then discuss suitable aquifers, as well as the human and physical challenges associated with diversification and managing resource development against various environmental and economic concerns.

Introduction During the COVID-19 pandemic, Computed Tomography (CT) departments have established additional acute capacity whilst maintaining essential services. The purpose of this study was to investigate the changes in service delivery, working practices and decision-making role of diagnostic radiographers during the pandemic. Methods We conducted an electronic cross-sectional survey of diagnostic radiographers working in CT during the COVID-19 pandemic. The survey was open for 6-weeks, with radiographers from all geographical regions encouraged to respond. The questionnaire explored social distancing, patient scheduling and departmental organisation; PPE usage; recognition and escalation of COVID-19 changes, patient management pathways and any training. Additionally, we sought the personal perspectives of radiographers through free text comments. Results Following exclusions, 180 responses were analysed. Service delivery changes included social distancing (59.4%; n= 107), restriction of referrals to those considered time-critical (63.3%; n=114) and dedicated COVID-19 scanners (66.1%; n=119). Working practices were impacted by a need to implement PPE, although variation in PPE worn for different scenarios was seen. Half of the radiographers were routinely reviewing asymptomatic outpatient images for common COVID-19 signs, despite 63.5% of respondents not receiving formal training. Ad hoc patient pathways were in place in 90.5% of cases with 35% indicating that this was radiographer-led. CT staff had experienced anxiety, fatigue, and low morale, but praised teamwork. Conclusions Radiographers were able to reduce the risk of transmission through social distancing, designated scanners, and PPE. This study has demonstrated that despite variance in practice, radiographers play a key role in identifying and triaging high-risk patients.

Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives.