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Eutrophication is a major global concern in lakes, caused by excessive nutrient loadings (nitrogen and phosphorus) from human activities and likely exacerbated by climate change. Present use of indicators to monitor and assess lake eutrophication is restricted to water quality constituents (e.g., total phosphorus, total nitrogen) and does not necessarily represent global environmental changes and the anthropogenic influences within the lake’s drainage basin. Nutrients interact in multiple ways with climate, basin conditions (e.g., socio-economic development, point-source, diffuse source pollutants), and lake systems. It is therefore essential to account for complex feedback mechanisms and non-linear interactions that exist between nutrients and lake ecosystems in eutrophication assessments. However, the lack of a set of water quality indicators that represent a holistic understanding of lake eutrophication challenges such assessments, in addition to the limited water quality monitoring data available. In this review, we synthesize the main indicators of eutrophication for global freshwater lake basins that not only include the water quality constituents but also the sources, biogeochemical pathways and responses of nutrient emissions. We develop a new causal network (i.e., multiple links of indicators) using the DPSIR (drivers-pressure-state-impact-response) framework that highlights complex interrelationships among the indicators and provides a holistic perspective of eutrophication dynamics in freshwater lake basins. We further review the 30 key indicators of drivers and pressures using seven cross-cutting themes: (i) hydro-climatology; (ii) socio-economy; (iii) land use; (iv) lake characteristics; (v) crop farming and livestock; (vi) hydrology and water management; (vii) fishing and aquaculture. This study indicates a need for more comprehensive indicators that represent the complex mechanisms of eutrophication in lake systems, to guide the global expansion of water quality monitoring networks, and support integrated assessments to manage eutrophication. Finally, the indicators proposed in this study can be used by managers and decision-makers to monitor water quality and set realistic targets for sustainable water quality management to achieve clean water for all, in line with Sustainable Development Goal 6.

River water quality is strongly affected by droughts and heatwaves worldwide. However, these effects have only been studied in a small number of river basins and regions, mainly in the US, Europe, or Australia. In this study, we analyse the large-scale responses in river water quality under droughts, heatwaves and compound events for 300,000+ water quality monitoring stations worldwide between 1980-2021. We include 16 water quality constituents in the analysis, grouped into general constituents (e.g. water temperature, salinity, dissolved oxygen), biological constituents (e.g. faecal coliform, biochemical oxygen demand) and emerging contaminants (e.g. pesticides and pharmaceuticals). Further, we assess the water quality responses to droughts and heatwaves in relation to climate, land use and level of wastewater treatment. We find a general deterioration in river water quality under droughts and heatwaves globally for most types of water quality constituents, with on average higher water temperatures (+27%), increases in salinity (+23%) and lower concentrations of dissolved oxygen (-17%). We also find that climate type, land use and level of wastewater treatment have a significant effect on the magnitude of water quality responses under droughts and heatwaves. The median increase in river temperature under compound drought-heatwaves strongly depends on climate, with for example higher increases in the Polar climate zone (+4.5°C) compared to the Tropical zone (+2.1°C). Increases in salinity under droughts are on average twice as large in irrigated regions compared to non-irrigated regions. Phosphorus and nitrogen concentrations in rivers can either increase or decrease during drought events, depending on the type of nutrient form (dissolved versus particulate) and land use (urban versus rural). Higher levels of wastewater treatment lead to a stronger reduction in faecal coliform (an indicator of pathogens) during droughts and heatwaves. Compared to previous local and regional-scale analyses, this study provides a more consistent and broader understanding of how droughts and heatwaves affect river water quality. In addition, the results from this study could be used to validate large-scale models of river water quality under droughts and heatwaves.

Pakistan is one of the most vulnerable counties in terms climate-change impacts on its agricultural productivity. Agriculture is not only the largest sector in Pakistan’s economy, the food security of its over 220 million inhabitants also strongly depends on its production. As Pakistan’s arid croplands are extensively irrigated, agricultural productivity is affected by increasing temperatures (projected to increase up to 6°C between 2000 and 2100 under a limited climate-change mitigation scenario), changes in water availability (i.e. river streamflow and groundwater resources) and atmospheric carbon dioxide concentrations ([CO2]; affecting both crop productivity and water use efficiency).Here we present the impacts of climate change on Pakistan’s primary cereal crops: wheat and rice. Impacts are quantified by combining several climate-change scenarios with a process-based coupled hydrological-crop model, VIC-WOFOST. VIC-WOFOST comprehensively estimates changes in crop growth, water resources and their interactions under climate change. Moreover, the role of elevated [CO2] on agricultural productivity and sustainable water use is specifically assessed. We then explore the possibilities and limitations of agricultural adaptation to enable sustainable food security for Pakistan under various climate-change and population growth scenarios.Our results show that climate-change will severely affect Pakistan’s agriculture, especially due increased temperatures and crop heat stress. However, climate-change adaptation can potentially mitigate some of these effects, especially for wheat production. Moreover, with sufficient agricultural adaptation, climate-change can even be beneficial for Pakistan’s agriculture due to the benefits of elevated [CO2]. While our study is focussed on Pakistan, it indicates pathways for sustainable food production under climate change that may also be important for other regions that strongly depend on irrigated agriculture.

By 2050 a doubling of crop production may be necessary to meet the growing worldwide food demands. Several studies have indicated the potential to increase crop production by reducing the so-called yield gap, i.e. the difference between potential crop production and actual crop production. The focus is commonly on closing the yield gap by increasing nutrient supply through fertilization and/or by increasing irrigated cropland extent. This could potentially achieve water-limited production (limited by rainfall) in rain-fed croplands and climate-limited production (limited by temperature and radiation) in irrigated croplands. For irrigated croplands this assumes sufficient water availability for irrigation. However, water availability for irrigation may be insufficient under higher nutrient supply. In addition, irrigation expansion in upstream areas might negatively affect water availability in downstream areas.We aim to quantitatively assess the worldwide water constrains to close yield gaps, accounting for various nutrient inputs. To assess water constrains we integrated a macro-scale hydrological model, the Variable Infiltration Capacity model (VIC-5 including human impacts; Droppers et al. in review), with a crop production model, the World Food Studies (WOFOST; de Wit et al. 2019) model. The VIC and WOFOST models were coupled for two-way interactions. The VIC model simulates the water and energy balance, including runoff, evapotranspiration, discharge and water stress for crop growth. Water stress is used in the WOFOST model to limit and adapt crop growth, e.g. limited biomass production and adjusted relative root production. Simulated crop characteristics (height, leaf area index, CO2 effects) are subsequently returned to VIC. By coupling these models we are able to assess the feedbacks between crop production and water availability globally.References:Droppers, B., Franssen, W. H. P., van Vliet, M. T. H., Nijssen, B., and Ludwig, F.: Simulating human impacts on global water resources using VIC-5. Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2019-251, in review, 2019.de Wit, A., Boogaard, H., Fumagalli, D., Janssen, S., Knapen, R., van Kraalingen, D., ... & van Diepen, K. (2019): 25 years of the WOFOST cropping systems model. Agricultural Systems, 168, 154-167, https://doi.org/10.1016/j.agsy.2018.06.018.

In Paris, France, December 2015, the Conference of the Parties (COP) to the United Nations Framework Convention on Climate Change (UNFCCC) invited the Intergovernmental Panel on Climate Change (IPCC) to provide a "special report in 2018 on the impacts of global warming of 1.5 °C above pre-industrial levels and related global greenhouse gas emission pathways". In Nairobi, Kenya, April 2016, the IPCC panel accepted the invitation. Here we describe the response devised within the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP) to provide tailored, cross-sectorally consistent impacts projections. The simulation protocol is designed to allow for (1) separation of the impacts of historical warming starting from pre-industrial conditions from other human drivers such as historical land-use changes (based on pre-industrial and historical impact model simulations); (2) quantification of the effects of additional warming up to 1.5 °C, including a potential overshoot and long-term effects up to 2299, compared to a no-mitigation scenario (based on the low-emissions Representative Concentration Pathway RCP2.6 and a no-mitigation pathway RCP6.0) with socio-economic conditions fixed at 2005 levels; and (3) assessment of the climate effects based on the same climate scenarios but accounting for simultaneous changes in socio-economic conditions following the middle-of-the-road Shared Socioeconomic Pathway (SSP2, Fricko et al., 2016) and differential bio-energy requirements associated with the transformation of the energy system to comply with RCP2.6 compared to RCP6.0. With the aim of providing the scientific basis for an aggregation of impacts across sectors and analysis of cross-sectoral interactions that may dampen or amplify sectoral impacts, the protocol is designed to facilitate consistent impacts projections from a range of impact models across different sectors (global and regional hydrology, global crops, global vegetation, regional forests, global and regional marine ecosystems and fisheries, global and regional coastal infrastructure, energy supply and demand, health, and tropical cyclones).

Background This study was conducted to describe the first experiences with hysterosalpingo-foam sonography (HyFoSy) as a first step routine office procedure for tubal patency testing. Methods A prospective observational cohort study was started in a university affiliated teaching hospital. In 2010, 73 patients with subfertility and a low risk of tubal pathology were examined. A non-toxic foam containing hydroxymethylcellulose and glycerol was applicated through a cervical applicator for contrast sonography (HyFoSy). Tubal patency was determined by transvaginal ultrasonographic demonstration of echogenic dispersion of foam in the Fallopian tube and/or the peritoneal cavity. Only in case patency could not be demonstrated, a hysterosalpingography (HSG) was performed as a control. Results In 67 out of 73 (92%) patients, a successful procedure was performed. In 57 out of 73 (78%) cases, there was no further need for a HSG. In five patients (5/73; 7%) tubal occlusion was confirmed by HSG and in five patients (5/73; 7%) there was discordance between HyFoSy and HSG. Of 73 patients, 14 (19%) conceived within a median of 3 months after the procedure. Conclusions HyFoSy is a successful procedure to demonstrate tubal patency as a first step office procedure.

labor are associated with operative delivery? Mariette Ruckert, Myrthe Peelen, Michelle van Vliet, Mieke ten Eikelder, Nikki van Desel, Katrien Oude Rengerink, Ben Willem Mol, Irene de Graaf Diakonessenhuis, Obstetrics and Gynecology, Utrecht, Netherlands, Academic Medical Center, Obstetrics and Gynecology, Amsterdam, Netherlands, Groene Hart Hospital, Obstetrics and Gynecology, Gouda, Netherlands, Kennemer Gasthuis, Obstetrics and Gynecology, Haarlem, Netherlands OBJECTIVE: At present, there is little scientific fundament behind the interpretation of physical examination during labor and delivery. We aimed to indentify which findings at the start of the second phase of labor were associated with instrumental vaginal delivery (IVD) and emergency caesarean section (ECS). STUDY DESIGN: We performed a prospective cohort study in five hospitals in the Netherlands. Consecutive laboring women, with a viable singleton pregnancy in cephalic presentation and a gestational age of at least 34 weeks, were included. We assessed the predictive value of antepartum and intrapartum characteristics and findings at digital examination prior to the second phase of labor (start pushing) for operative delivery (OD) using logistic regression analysis. We selected variables based on literature and clinical experience. Backward selection was used to develop a prediction model, predictors with a p 0.157 remained in the final model. The discriminative ability of the model was assessed using ROC analyses (perfect when AUC 1). The correspondence between the predicted probability for OD and the observed number of operative deliveries over groups was assessed with a calibration plot (perfect when all points are on the diagonal). RESULTS: Between December 2010 and October 2011, we included 473 women, of whom 74 (16%) had a VID and 22 (5%) an ECS. For 425 women, data on all relevant variables were available. Predictors for OD at start of the second phase of labor were 10 cm dilatation, Caucasian etnicity, nulliparity, epidural analgesia, spontaneous start, molding, engagement and position of the fetal head (Table). The model including these variables showed good discriminative ability: AUC ROC 0.82 (95% CI 0.77-0.87). The model calibrated well (Figure). CONCLUSION: At start of the second phase of labor, antepartum and intrapartum characteristics can predict the need for OD. The prediction model may be implied as a useful tool for clinical decision making and assembling logistics at the delivery ward. 776 The validity of the variable “NICU admission” as an outcome measure for neonatal morbidity Nora Danhof, Melanie Wiegerinck, Anton van Kaam, Ben Willem Mol Academic Medical Center, Obstetrics & Gynecology, Amsterdam, Netherlands OBJECTIVE: The variable “neonatal intensive care (NICU) admission” is a frequently used outcome measure in clinical studies, as can be illustrated by the fact that it is reported as such in nearly one hundred Cochrane reviews from the Pregnancy and Childbirth Group. We addressed the question whether NICU admission is a valid surrogate outcome measure for neonatal morbidity, specifically when comparing different birth settings with different access to the NICU. STUDY DESIGN: We performed a retrospective cohort study among neonates admitted at the NICU of a tertiary hospital in the Netherlands during a ten-year period. The inclusion was restricted to singletons born at term, who were admitted at the NICU for delivery-related morbidity within 24 hours of birth. Patient characteristics and admission data were compared for four groups based on the line of care during delivery, i.e. home birth (group Ia), midwive lead hospital delivery (Ib), secondary care (II) and tertiary care (III). We specifically looked at the mortality rate, defined as the percentage of children that died at any time during NICU admission. RESULTS: We studied 871 newborns of which 53 were born at home, 25 under supervision of a midwife in the hospital, 166 in secondary Calibration plot, showing the average observed operative delivery rate (Y-axis) against the average calculated operative delivery rate (X-axis)