Характеристика загрязнения прибрежных вод у Карадагского заповедника по данным оптических измерений

На основе анализа данных оптических наблюдений в рамках комплексных океанографических экспедиций, проведенных сотрудниками ИнБЮМ НАНУ и МГИ НАНУ 22, 23 мая 2007 г. и 21, 22 июля 2009 г. в прибрежных водах Черного моря у Карадагского заповедника, выполнены оценки загрязнения рассматриваемой акватории растворенным органическим веществом искусственного происхождения и растворенными нефтепродуктами. Определены концентрации, источники и пути распространения суммарной взвеси и загрязняющих веществ. Зафиксирован рост степени загрязнения заповедной акватории в течение двух последних лет.На основі аналізу даних оптичних спостережень у рамках комплексних океанографічних експедицій, проведених співробітниками ІнБЮМ НАНУ та МГІ НАНУ 22, 23 травня 2007 р. та 21, 22 липня 2009 р. у прибережних водах Чорного моря біля Карадазького заповідника, виконано оцінки забруднення розглянутої акваторії розчиненою органічною речовиною штучного походження та розчиненими нафтопродуктами. Визначено концентрації, джерела та шляхи поширення сумарної зваженої речовини та забруднюючих речовин. Зафіксовано зростання ступеню забруднення заповідної акваторії протягом двох останніх років.On the base of analysis of optical observations’ data within the framework of complex oceanographic expeditions, undertaken by employers of IBSS and MHI of National academy of sciences of Ukraine on 22, 23 May 2007 and 21, July 22 2009 in the coastal waters of the Black sea beside the Karadag reserve, estimations of water borne contaminations with dissolved organic material by man made birth and dissolved oil are executed. The concentrations, sources and the ways of the total suspended matter and polluting material spreading are defined. Increase in pollution percentage in waters of the reserve is fixed for two last years

A conceptual model for the analysis of multi-stressors in linked groundwater–surface water systems

Groundwater and surface water are often closely coupled and are both under the influence of multiple stressors. Stressed groundwater systems may lead to a poor ecological status of surface waters but to date no conceptual framework to analyse linked multi-stressed groundwater – surface water systems has been developed. In this paper, a framework is proposed showing the effect of groundwater on surface waters in multiple stressed systems. This framework will be illustrated by applying it to four European catchments, the Odense, Denmark, the Regge and Dinkel, Netherlands, and the Thames, UK, and by assessing its utility in analysing the propagation or buffering of multi-stressors through groundwater to surface waters in these catchments. It is shown that groundwater affects surface water flow, nutrients and temperature, and can both propagate stressors towards surface waters and buffer the effect of stressors in space and time. The effect of groundwater on drivers and states depends on catchment characteristics, stressor combinations, scale and management practises. The proposed framework shows how groundwater in lowland catchments acts as a bridge between stressors and their effects within surface waters. It shows water managers how their management areas might be influenced by groundwater, and helps them to include this important, but often overlooked part of the water cycle in their basin management plans. The analysis of the study catchments also revealed a lack of data on the temperature of both groundwater and surface water, while it is an important parameter considering future climate warming

A review of the dodo and its ecosystem: insights from a vertebrate concentration Lagerstätte in Mauritius

The dodo Raphus cucullatus Linnaeus, an extinct and flightless, giant pigeon endemic to Mauritius, has fascinated people since its discovery, yet has remained surprisingly poorly known. Until the mid-19th century, almost all that was known about the dodo was based on illustrations and written accounts by 17th century mariners, often of questionable accuracy. Furthermore, only a few fragmentary remains of dodos collected prior to the bird's extinction exist. Our understanding of the dodo's anatomy was substantially enhanced by the discovery in 1865 of subfossil bones in a marsh called the Mare aux Songes, situated in southeastern Mauritius. However, no contextual information was recorded during early excavation efforts, and the majority of excavated material comprised larger dodo bones, almost all of which were unassociated. Here we present a modern interdisciplinary analysis of the Mare aux Songes, a 4200-year-old multitaxic vertebrate concentration Lagerstätte. Our analysis of the deposits at this site provides the first detailed overview of the ecosystem inhabited by the dodo. The interplay of climatic and geological conditions led to the exceptional preservation of the animal and associated plant remains at the Mare aux Songes and provides a window into the past ecosystem of Mauritius. This interdisciplinary research approach provides an ecological framework for the dodo, complementing insights on its anatomy derived from the only associated dodo skeletons known, both of which were collected by Etienne Thirioux and are the primary subject of this memoir.publishedVersio

Effects of climate change on coastal groundwater systems: A modeling study in the Netherlands

Climate change in combination with increased anthropogenic activities will affect coastal groundwater systems throughout the world. In this paper, we focus on a coastal groundwater system that is already threatened by a relatively high seawater level: the low‐lying Dutch Delta. Nearly one third of the Netherlands lies below mean sea level, and the land surface is still subsiding up to 1 m per century. This densely populated delta region, where fresh groundwater resources are used intensively for domestic, agricultural, and industrial purposes, can serve as a laboratory case for other low‐lying delta areas throughout the world. Our findings on hydrogeological effects can be scaled up since the problems the Dutch face now will very likely be the problems encountered in other delta areas in the future. We calculated the possible impacts of future sea level rise, land subsidence, changes in recharge, autonomous salinization, and the effects of two mitigation countermeasures with a three‐dimensional numerical model for variable density groundwater flow and coupled solute transport. We considered the effects on hydraulic heads, seepage fluxes, salt loads to surface waters, and changes in fresh groundwater resources as a function of time and for seven scenarios. Our numerical modeling results show that the impact of sea level rise is limited to areas within 10 km of the coastline and main rivers because the increased head in the groundwater system at the coast can easily be produced though the highly permeable Holocene confining layer. Along the southwest coast of the Netherlands, salt loads will double in some parts of the deep and large polders by the year 2100 A.D. due to sea level rise. More inland, ongoing land subsidence will cause hydraulic heads and phreatic water levels to drop, which may result in damage to dikes, infrastructure, and urban areas. In the deep polders more inland, autonomous upconing of deeper and more saline groundwater will be responsible for increasing salt loads. The future increase of salt loads will cause salinization of surface waters and shallow groundwater and put the total volumes of fresh groundwater volumes for drinking water supply, agricultural purposes, industry, and ecosystems under pressure

Fast calculation of groundwater exfiltration salinity in a lowland catchment using a lumped celerity/velocity approach

To support operational water management of freshwater resources in coastal lowlands, a need exists for a rapid, well-identifiable model to simulate salinity dynamics of exfiltrating groundwater. This paper presents the lumped Rapid Saline Groundwater Exfiltration Model (RSGEM). RSGEM simulates groundwater exfiltration salinity dynamics as governed by the interplay between water velocity, gradually adjusting the subsurface salinity distribution, and pressure wave celerity, resulting in a fast flow path response to groundwater level changes. RSGEM was applied to a field site in the coastal region of the Netherlands, parameter estimation and uncertainty analysis were performed using generalized likelihood uncertainty estimation. The model showed good correspondence to measured groundwater levels, exfiltration rates and salinity response. Moreover, RSGEM results were very similar to a detailed, complex groundwater flow and transport model previously applied to this field site

Land subsidence by peat oxidation leads to enhanced salinization through boils in Dutch polders

Peat oxidation in deep Dutch polders leads - in addition to subsidence - to the development of new saline boils, enhancing the salinization of these polders. This on-going process is studied in detail in the Middelburg-Tempelpolder. The objective of the study was to get more in-depth knowledge about this process and to assess it for the present situation and for future landscapes (after 10, 50, 100 and 500 years).</p

Land subsidence by peat oxidation leads to enhanced salinization through boils in Dutch polders

Peat oxidation in deep Dutch polders leads - in addition to subsidence - to the development of new saline boils, enhancing the salinization of these polders. This on-going process is studied in detail in the Middelburg-Tempelpolder. The objective of the study was to get more in-depth knowledge about this process and to assess it for the present situation and for future landscapes (after 10, 50, 100 and 500 years).</p

Natural saltwater upconing by boils: field measurements and numerical modeling

Natural saltwater upconing caused by the preferential groundwater discharge of boils is a key proce ss in the salinization of Dutch deep polders. The factors controlling upconing by boil discharge and boil water salinities are poorly constrained and have not been previously documented. We addressed this knowl- edge gap by investigating upconing mechanisms using field measurements and numerical simulation s of simplified situations. Boils occur as conduits in the upper aquitard connecting the underlying aquifer to the surface and allowing groundwater to discharge at rates up to 100 m3 d?1 with Cl concentrations up to5gL?1. Boils are found as isolated features or clustered in small areas of 20–100m2. Field observations show that preferential flow through boils creates localized and narrow saltwate r upconing spikes, caus- ing the elevated boil water salinities. Modeling results indicate that boil water in Dutch polders com- prises mixtures of groundwater from a wide range of depths and salinities with larger contributions from shallower and less saline groundwater than from the deeper and more saline water. Similar to pre- vious numerical studies of pumping-in duced upconing, the numerical results show that the most impor- tant factors controlling the boil salinity in Dutch polders are boil discharge, the horizontal hydraulic conductivity of the aquifer, the depth of the transition zone and the salinit y (or density) contrast within the aquifer. When boils are clustered, natural saltwater upconing is a function of the total discharge of a boil cluster, whereas the boil-to-boil salinity variations within a cluster are determined by the discharge of individual boils and their position relative to neighboring boils. Regional lateral flow significantly mod- ifies flow patterns by dividing the groundwater flow system into a local boil system overlying the regio- nal flow system. Despite this, regional flow has only a minor effect on the relative contribu tions of saline and fresh groundwater to boil discharge and thus on boil salinity as well

Rainwater lens dynamics and mixing between infiltrating rainwater and upward saline groundwater seepage beneath a tile-drained agricultural field

Thin rainwater lenses (RW-lenses) near the land surface are often the only source of freshwater in agricultural areas with regionally-extensive brackish to saline groundwater. The seasonal and inter-annual dynamics of these lenses are poorly known. Here this knowledge gap is addressed by investigating the transient flow and mixing processes in RW-lenses beneath two tile-drained agricultural fields in the Netherlands. Evidence of RW-lens dynamics was systematically collected by monthly ground and soil water sampling, in combination with daily observations of water table elevation, drain tile discharge and drain water salinity. Based on these data, and numerical modeling of the key lens characteristics, a conceptual model of seasonal lens dynamics is presented. It is found that variations in the position of the mixing zone and mixing zone salinities are small and vary on a seasonal timescale, which is attributed to the slow transient oscillatory flow regime in the deepest part of the lens. The flow and mixing processes are faster near the water table, which responds to recharge and evapotranspiration at a time-scale less than a day. Variations of drain tile discharge and drain water salinity are also very dynamic as they respond to individual rain events. Salinities of soil water can become significantly higher than in the groundwater. This is attributed to the combined effect of capillary rise of saline groundwater during dry periods and incomplete flushing by infiltrating freshwater due to preferential flow through cracks in the soil. The results of this study are the key to understanding the potential impact of future climate change and to designing effective mitigating measures such as adapting tile-drainage systems to ensure the future availability of freshwater for agriculture