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Environmental degradation of the Chesapeake Bay (CB) and its sub-estuaries has been linked to population growth in the surrounding coastal zone, rapid development in the watershed and resultant nutrient loading into the Bay. Consequently, the federal government and its partners have developed restoration plans to mitigate the effects of eutrophication and improve essential ecosystem functions, though few restoration plans have considered the interactive effects of climate change. Climate change and other anthropogenic drivers are causing changes in ecosystem structure and function, thereby impacting the beneficial services ecosystems provide. While some studies have attempted to quantitatively predict the benefits of ecosystem restoration under current conditions, research is needed to determine whether restored systems will be sustainable and continue to provide ecosystem services under changing conditions. This study examined how climate warming and sea level rise (SLR) might affect the sustainability of ecosystem services resulting from the proposed U.S. Army Corps of Engineers (USACE) Lynnhaven River Basin Ecosystem Restoration Plan (LRBERP). A system-wide prediction of marsh survival in the Lynnhaven was calculated by estimating the time period when Spartina alterniflora (smooth cordgrass) would submerge based on predicted sea level rise and marsh accretion for the region. In addition, a reduced complexity ecosystem model was applied to the Lynnhaven River to evaluate survival and sustainability of ecosystem services provided by S. alterniflora, Zostera marina (eelgrass), Ruppia maritima (widgeon grass), and Crassostrea virginica (Eastern oyster) reef habitat, under existing conditions as well as predicted climate warming (+1, 2, 3, and 5 °C) and sea level rise (+0.49, 0.99, 1.69, 2.29 m) scenarios for the region. The major findings from the model simulations and marsh analysis indicate that climate warming and SLR will affect the sustainability and capacity of restored submerged aquatic vegetation (SAV), oysters and marsh habitat to provide ecosystem services in the Lynnhaven River. This investigation calls into question the assumption that marshes will accrete indefinitely to keep pace with accelerating rates of sea level rise. Predicted submergence of S. alterniflora marshes by 2100 will limit their capacity to provide ecosystem services. Model predictions of S. alterniflora biomass decreased across the temperature scenarios with complete die-off under the +5°C scenario. Z. marina and R. maritima biomass decreased across the SLR scenarios with complete die-off of R. maritima under the 0.49 m scenario. This modeling result is consistent with the literature that R. maritima is more sensitive to light limitation than Z. marina. Z. marina biomass decreased across the temperature scenarios with complete die-off under the 5°C scenario whereas R. maritima biomass increased under the temperature scenarios. The positive effects of warming on R. maritima were offset by the negative impacts from SLR. There was a complete die-off of Z. marina and R. maritima biomass under the combined SLR/temperature scenario. The combination of stressors will likely have negative effects on Z. marina and R. maritima biomass in the polyhaline section of the Bay.

Science means “to know", a process for gaining knowledge and an understanding of the natural world. Students need to be involved in active learning. In other words, they must do science, not just hear about it. Good science encourages students to gain knowledge by doing science: observing, questioning, exploring, making and testing hypotheses, comparing predictions, evaluating data, and communicating conclusions. This unit plan is designed to incorporate the components of fresh water, ecology, water quality, and a class-wide science project. Each lesson addresses selected standards from the state core curriculum and has specific objectives that are tied to the learning objectives associated with the state core curriculum. The unit starts with five lessons that introduce fresh water and the role of fresh water in our lives. Students will learn the stages of the water cycle and participate in discussions and activities that will allow them to see the critical need to conserve, protect, and manage water properly. The next four lessons focus on the importance of biodiversity and human impact on biodiversity. The last part of the unit pulls the lessons on fresh water and ecology together into a class-wide science project. Students will study how abiotic factors affect water quality and then participate in a project relating those concepts in a study of Hobble Creek, near Springville, Utah. The unit finishes with group presentations about the science project and then a unit test. There is a good mix of regular classroom instruction and activities along with variation in learning styles. There is note taking, art expression, visual learning, verbal expression, group interaction, guided inquiry, different types of assessment, discussions involving higher level thinking, and hands on learning. The unit takes up nearly four weeks of school time. It will take considerable planning and preparation to teach the lessons, plan and carry out the activities and provide the needed accommodations.

Yes / The shortage of fresh water resources is a global problem which requires a prompt solution. Thus, the multi effect distillation (MED) was successfully used for the production of fresh water from seawater. Despite the use of MED desalination system extensively, the influence of the number of effects on the fresh water production cost has not been covered in the open literature. Thus, this paper tries to rectify this specific challenge via simulation at given operating conditions of seawater salinity and temperature. The study is performed using a detailed mathematical model contains the suitable cost correlations. gPROMS model builder suite has been used to carry out an extensive simulation. The results of the study show that the lowest fresh water production cost can be achieved at an optimal number of effects of 17 for a certain operating conditions.

Examination of an important new 319m core of lake sediment recovered from Ioannina in NW Greece has attempted to relate changes in the lake to variations in the regional climate of south-central Europe over the last 600,000 years. The site is known to have been extremely sensitive to past climatic change for three reasons: (i) temperate vegetation persisted throughout glacial stages (albeit at low frequencies), so the vegetational response to climatic change would therefore have been almost immediate; (ii) the extreme thickness of the sediments suggests that accumulation rates were high (at times, > 1m per thousand years), which has enabled high-resolution palaeoclimatic reconstructions; and (iii) precipitation of authigenic carbonate has preserved a remarkably sensitive proxy record of productivity variations for most of the lake's history. Well-defined shifts from glacial - interglacial mode have been correlated with vegetational changes identified in a core previously analysed from the same basin (using magnetic susceptibility profiles), enabling tentative correlations to be suggested with other European terrestrial sequences and with the marine oxygen isotope record, back to marine isotope stage 16. Twelve AMS radiocarbon determinations from the upper part of the core, together with the identification of a series of reversed palaeomagnetic events within the Brunhes chron, support the proposed age model for the sequence. The sediments at Ioannina, unlike most of the other long terrestrial European sequences, are calcareous and contain mollusc and ostracod assemblages. Part of this project has involved a comprehensive review of Quaternary and modem aquatic faunas from the lake, as well as the description, illustration and critical assessment of several poorly-known endemic taxa. Faunal assemblage data have been used to provide valuable information concerning the variable response of lake-level to climatic change over time. Convincing new mollusc an evidence indicates low lake-levels at the Last Glacial Maximum, agreeing with regional pollen data, but conflicting with geomorphological evidence derived from Kastritsa, a well-documented nearby Palaeolithic cave site. It is suggested that this discrepancy may be a result of subsequent tectonic uplift of the rockshelter. In addition, stable isotopic analyses of both the ostracods and the bulk carbonate within the sediments have contributed towards deriving a comprehensive palaeoenvironmental history for the site. Although the study analysed physical, biological and geochemical aspects of the entire core, two distinct parts of the record were selected for more detailed investigation. High-resolution analysis over the last interglacial (the Eemian) has revealed evidence for a clear, two-step deglaciation at the beginning of the period, known from elsewhere as the Zeifen-Kattegat Oscillation. Climatic instability has also been detected within the full interglacial. Comparisons are drawn with a range of other Eemian records from across Europe, as well as the Greenland ice cores. High-resolution analysis of the period from the end of the last glacial to the present day has also revealed evidence for climatic instability. A cool and arid oscillation is demonstrated by several climatic proxies that may constitute the first recognition of the Younger Dryas stadial from Greece. A shorter, but more subdued cooling event has also been detected during the first half of the Holocene, which may correspond with a widespread climatic oscillation from high-resolution terrestrial, marine and ice core records that has been dated to between 7,500 and 8,000 years BP.

Integrated water management is a wicked public policy problem with no clear path to resolution. This dissertation is an in-depth qualitative comparative analysis of two collaborative governance processes created to tackle complex water problems in New Zealand and Oregon, U.S.A. Both cases convened a wide range of state and non-state actors in efforts to find common ground, build consensus for change, and develop innovative water policy solutions. The goal of this comparative case study analysis is to gain a better understanding of collaborative network governance frameworks as applied to integrated water management and primary factors for success. The proposition posits that collaborative networks involving public, private, and non-profit actors are better equipped than government-driven efforts to develop desired outcomes. To test this proposition, the research questions probe the role of state and non-state policy actors, conditions for collaboration, strength of actor ties, development of trust and social capital, barriers to success, and the role of climate change as a policy driver in these two case studies. The comparative case study analysis yields fascinating insights that adds to the network governance literature. In the New Zealand case, a collaborative-led process called the Land and Water Forum (LAWF) showed that this ongoing network offers benefits to creating consensus on complex water issues. LAWF succeeded in moving policy conversations forward where previous government-led efforts had failed. Within the LAWF collaborative network, non-state actors formed strong ties; however, relationships with state actors exhibited weaker ties. With Oregon's integrated water policy, a collaborative network approach created a more conducive environment for meaningful dialogue among vested interests, and built some levels of interdependency and trust, thus generating a wider array of policy options than through previous legislative and bureaucratic efforts. However, long-standing political, legal, and institutional challenges continue to constrain effective integrated water management and the delivery of integrated outcomes in Oregon. The Oregon case did not exhibit strong leadership within the collaborative to broker challenging policy issues. Also, it faced implementation challenges as one state agency was given responsibility for stewarding integrated water management but lacked authority for implementation or coordination with other state agencies. Overcoming fragmented natural resource governance arrangements remains a daunting challenge. This research revealed three key findings: (1) in both cases, collaborative network governance worked well for framing and designing new integrated water policies, but encountered implementation challenges; (2) managing the complexities around the intersection of top-down, vertical command and control governance with horizontal collaborative approaches remains an ongoing challenge to New Public Governance; and (3) the two cases represent examples of the use of formal and informal processes for policy development. The benefits of collaborative governance for policy development are substantial, and the limitations appear to be obstacles to overcome and not fatal flaws. The main challenge lies in transitioning from policy and planning to implementing changes on the ground affecting the way we manage water today and in the future.

Thesis (MSc. (Geography and Environmental Science)) -- University of Limpopo, 2015. / Fresh water is a finite and vulnerable resource, essential to sustain life, development and the environment. Growth in population and economic activities have contributed to water scarcity, which is a frequent challenge in rural and township communities in South Africa. This study aimed at investigating onsite greywater reuse as a water conservation method in Lepelle-Nkumpi local municipality, Limpopo province. The study described the socio-economic characteristics, assessed the accessibility and availability of water supply, and ascertained the coping mechanisms for water scarcity as well as the perceptions and reuse of greywater. Four percent respondents each were selected from two settlements, namely, Mashite village and Lebowakgomo township (Zone F). Mashite village had a population size of 5314 people (1231 households) and Lebowakgomo Zone F had 5903 people and (1924 households). A systematic random sampling method was used to select the required households from the two settlements. Both open and close ended questionnaires were used. A Geographical Positioning System was also used to collect the absolute location of available taps in the study area. Data collected were analysed using SPSS version-22 and Arc GIS 10.1. The study found out that the socio-economic characteristics of importance on onsite greywater reuse included highest qualification, household size and employment status, but they varied in these two areas. In Mashite village the majority of the respondents went to secondary school (59%) as compared to Lebowakgomo Zone F where the majority (72%) attained tertiary qualification. Household size mean in Mashite is 6.18 as compared to Lebowakgomo Zone F (2.77). Sixty four percent of respondents in Mashite village were unemployed, whereas in Lebowakgomo 69% were employed. Water usage in the two areas differed; in Mashite village where they use less water (250 to 840 litres) as compared to Lebowakgomo Zone F, where more water is used (5900 to 8001 litres). In Mashite village, 87% of the respondents could not access water due to inaccessibility of taps and unavailability of water as compared to Lebowakgomo zone F (100%). It was also found that the Mashite community sometimes go for a period of two to three months without tap water whereas in Lebowakgomo water was comparatively regular. As a result both communities resorted to rainwater harvesting and greywater reuse. Seventy six percent (76%) of respondents in Mashite village and 30% of the respondents in ii Lebowakgomo Zone F harvested rainwater as a coping mechanism of water scarcity. Perceptions of greywater reuse were higher (76%) in Lebowakgomo Zone F compared to Mashite village (49%). A higher percentage of Mashite village respondents (98%) reuse greywater compared to Lebowakgomo Zone F respondents (59%). Both areas use greywater as water conservation method. These results reinforce the potential of domestic greywater reuse as an alternative for freshwater requirement. Greywater reuse as a water conservation method especially in villages can be used to alleviate the extent of water scarcity. / National Research Foundation (NRF)

Silver nanoparticles (AgNPs) are known to cause ecotoxic effects, but there are no existing derived ambient water quality criteria (AWQC) for these nanomaterials to protect freshwater aquatic life due to insufficient toxicological data. We exposed Hyalella azteca to silver nitrate, citrate-coated AgNPs (citrate-AgNPs), and polyvinylpyrrolidone-coated AgNPs (PVP-AgNPs) in a 10-day and 28-day water-only static renewal system with clean sand as a substrate for the amphipods and compared their point estimates with the United States Environmental Protection Agency (USEPA) AWQC for silver. We observed that all treatments decreased the survival, growth, and biomass of H. azteca, and the order of toxicity was AgNO > citrate-AgNPs > PVP-AgNPs. The LC50s of AgNO, citrate-AgNPs, and PVP-AgNPs were 3.0, 9.6, and 296.0 µg total Ag L, respectively, for the acute exposure and 2.4, 3.2, and 61.4 µg total Ag L, respectively, for the chronic exposure. Acute and chronic EC20s of citrate-AgNPs ranged from 0.5 to 3.5 µg total Ag L while that of PVP-AgNPs ranged from 31.2 to 175 µg total Ag L for growth and biomass. Both Ag released from AgNPs and the nanoparticles contributed to the observed toxicity. The dissolution and toxicity of AgNPs were influenced by surface coating agents, particle size, and surface charge. Most point estimates for AgNPs were above AWQC for silver (4.1 µg L) and the lowest concentration (0.12 µg/L) at which Ag is expected to cause chronic adverse effects to freshwater aquatic life. Our study demonstrates that the current AWQC for silver, in general, is protective of freshwater aquatic life against AgNPs tested in the present study.

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Many recent studies have sought to understand the response of barrier islands and their attendant marshes to sea level rise. The Mississippi River delta plain, specifically the Chandeleur Islands and associated interior wetlands in eastern Louisiana, serves as an excellent natural laboratory for studying these responses. This region is presently undergoing the highest rates of shoreline erosion (> 15 m yr -1) in North America as wetlands are converted to open water in a regime of subsidence-driven rapid relative sea-level rise (~1 cm yr-1). Three conceptual models were developed based on the geomorphic relationships observed in the marsh that describe and predict shoreline processes as the Chandeleur Islands continue to disintegrate and submerge. These models indicate that shells are the dominant shoreline-forming material in the marsh due to the lack of sand-rich strata in the subsurface of the marsh.