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Climate change is altering naturally fluctuating environmental conditions in coastal and estuarine ecosystems across the globe. Departures from long-term averages and ranges of environmental variables are increasingly being observed as directional changes [e.g., rising sea levels, sea surface temperatures (SST)] and less predictable periodic cycles (e.g., Atlantic or Pacific decadal oscillations) and extremes (e.g., coastal flooding, marine heatwaves). Quantifying the short- and long-term impacts of climate change on tidal marsh seascape structure and function for nekton is a critical step toward fisheries conservation and management. The multiple stressor framework provides a promising approach for advancing integrative, cross-disciplinary research on tidal marshes and food web dynamics. It can be used to quantify climate change effects on and interactions between coastal oceans (e.g., SST, ocean currents, waves) and watersheds (e.g., precipitation, river flows), tidal marsh geomorphology (e.g., vegetation structure, elevation capital, sedimentation), and estuarine and coastal nekton (e.g., species distributions, life history adaptations, predator-prey dynamics). However, disentangling the cumulative impacts of multiple interacting stressors on tidal marshes, whether the effects are additive, synergistic, or antagonistic, and the time scales at which they occur, poses a significant research challenge. This perspective highlights the key physical and ecological processes affecting tidal marshes, with an emphasis on the trophic linkages between marsh production and estuarine and coastal nekton, recommended for consideration in future climate change studies. Such studies are urgently needed to understand climate change effects on tidal marshes now and into the future.

A growing body of research indicates that opinions about long-term climate change and other natural resource issues can be significantly affected by current weather conditions (e.g., outside air temperature) and other highly contingent environmental cues. Although increased severity and frequency of droughts is regarded as a likely consequence of anthropogenic climate change, little previous research has attempted to relate the experience of drought with public attitudes about water supply or water-related climate change issues. For this study, a large set ( n  = 3,163) of public survey data collected across nine states of the southern United States was spatio-temporally linked with records of short-term (~12 weeks) and long-term (~5 years) drought condition at the level of each respondent’s zip code. Multivariate ordinal logistic regression models that included numerous other independent variables (environmental ideology, age, gender, education, community size, residency duration, and local annual precipitation) indicated highly significant interactions with long-term drought condition, but showed no significant effect from short-term drought condition. Conversely, attitudes about water-related climate change showed highly significant interactions with short-term drought, with weaker to no effects from long-term drought. While the finding of significant effects from short-term drought condition on opinions about future drought is broadly consistent with previous public opinion research on climate change, the finding of water supply attitudes being more responsive to longer term drought condition is, to our knowledge, a novel result. This study more generally demonstrates the methodological feasibility and applied importance of accounting for local drought condition when public opinion information is used to evaluate outreach programs for water conservation and climate change.

Climate change has far-reaching effects on human and ecological systems, requiring collaboration across sectors and disciplines to determine effective responses. To inform regional responses to climate change, decision-makers need credible and relevant information representing a wide swath of knowledge and perspectives. The southeastern U. S. State of Georgia is a valuable focal area for study because it contains multiple ecological zones that vary greatly in land use and economic activities, and it is vulnerable to diverse climate change impacts. We identified 40 important research questions that, if answered, could lay the groundwork for effective, science-based climate action in Georgia. Top research priorities were identified through a broad solicitation of candidate research questions (180 were received). A group of experts across sectors and disciplines gathered for a workshop to categorize, prioritize, and filter the candidate questions, identify missing topics, and rewrite questions. Participants then collectively chose the 40 most important questions. This cross-sectoral effort ensured the inclusion of a diversity of topics and questions (e.g., coastal hazards, agricultural production, ecosystem functioning, urban infrastructure, and human health) likely to be important to Georgia policy-makers, practitioners, and scientists. Several cross-cutting themes emerged, including the need for long-term data collection and consideration of at-risk Georgia citizens and communities. Workshop participants defined effective responses as those that take economic cost, environmental impacts, and social justice into consideration. Our research highlights the importance of collaborators across disciplines and sectors, and discussing challenges and opportunities that will require transdisciplinary solutions.

Raw poultry litter has certain drawbacks for energy production such as high ash and moisture content, a corrosive nature, and low heating values. A combined solution to utilization of raw poultry litter may involve fractionation and pyrolysis. Fractionation divides poultry litter into a fine, nutrient-rich fraction and a coarse, carbon-dense fraction. Pyrolysis of the coarse fraction would remove the corrosive volatiles as bio-oil, leaving clean char. This paper presents the effect of fractionation and pyrolysis process parameters on the calorific value of char and on the characterization of bio-oil. Poultry litter samples collected from three commercial poultry farms were divided into 10 treatments that included 2 controls (raw poultry litter and its coarse fraction having particle size greater than 0.85 mm) and 8 other treatments that were combinations of three factors: type (raw poultry litter or its coarse fraction), heating rate (30 or 10 °C/min), and pyrolysis temperature (300 or 500 °C). After the screening process, the poultry litter samples were dried and pyrolyzed in a batch reactor under nitrogen atmosphere and char and condensate yields were recorded. The condensate was separated into three fractions on the basis of their density: heavy, medium, and light phase. Calorific value and proximate and nutrient analysis were performed for char, condensate, and feedstock. Results show that the char with the highest calorific value (17.39 ± 1.37 MJ/kg) was made from the coarse fraction at 300 °C, which captured 68.71 ± 9.37% of the feedstock energy. The char produced at 300 °C had 42 ± 11 mg/kg arsenic content but no mercury. Almost all of the Al, Ca, Fe, K, Mg, Na, and P remained in the char. The pyrolysis process reduced ammoniacal-nitrogen (NH 4 -N) in char by 99.14 ± 0.47% and nitrate-nitrogen (NO 3 -N) by 95.79 ± 5.45% at 500 °C.

Soil erosion is one of the biggest contributors to nonpoint source pollution in the United States. Soil loss rates from construction sites are 10 to 20 times that of agricultural lands. The use of surface applied organic amendments has been shown to reduce runoff and erosion through enhanced vegetation growth and soil quality characteristics. The objective of this study was to evaluate the vegetation growth and soil quality effects from compost blanket and hydroseed applications to soils disturbed by construction activities. Four types of compost blankets, two hydroseeded treatments (silt fence and mulch filter berm) and a bare soil (control) were applied in field test plots. Treatments were seeded with common Bermuda grass ( Cynodon dactylon ). Vegetative growth (percent cover and biomass of weeds and grasses) and soil quality characteristics were evaluated periodically over one year and 18 months, respectively. Results showed compost blankets provided an average of 2.75 times more vegetative cover than hydroseed after three months. After one year, cover was similar, but hydroseed had significantly greater weed biomass than compost and a greater ratio of weed biomass relative to Bermuda grass biomass. One type of compost blanket increased surface soil extractable organic carbon, and another type increased organic matter in 0 to15 cm (0 to 6 in) soil depths relative to hydroseed treated soils. A one-time application of hydroseed that included mineral phosphorus (P) fertilizer elevated surface soil P after 18 months. On construction sites where disturbed soils are prone to erosion and vegetation establishment is required, compost applications will promote quicker vegetation cover with less weed growth than hydroseeding. Some compost erosion control blankets have the ability to increase soil quality characteristics relative to hydroseed applications within 18 months of application.

The Silt-Saver Belted Strand Retention Fence (BSRF) was compared with the traditional type C silt fence to determine whether it would be acceptable for use as a sediment barrier. ASTM standard methods were used to evaluate flow-through and sediment removal efficiency using three different soils. For flow without sediment, there were no statistical differences, although the BSRF showed a slightly higher flow rate than the type C fence. Flow rates with sediment were generally 30% to 85% lower on the BSRF than the type C fence with greater differences observed with finer particle sizes and double concentration runs. This indicates the influence of soil particles on flow rate and suggests that sediment trapped behind the fence is controlling flow rate more than the fence itself. Results from analysis of effluent and sediment removal efficiency indicated that BSRF was more effective at retaining sediment behind the fence. Both suspended solids content and turbidity of the effluent were lower using the BSRF material than type C fence material for all test conditions. Sediment removal efficiencies for BSRF were significantly higher for all three tested soils. Additional tests were conducted using variations of the ASTM standard, and these tests showed similar trends. Testing also indicated that design of the supporting apparatus was sufficient for withstanding overtopping with water. While no testing program can provide results to prove an application will function under all conditions that will be encountered in the field, this testing indicates that the Silt-Saver BSRF should be an effective alternative to the standard type C silt fence.

Rainfall patterns, soil factors, topography, climate, and land use may all influence runoff. To minimize environmental concerns, excessive runoff should be avoided on areas where manure has been applied. Management practices used to control runoff include contouring, strip cropping, conservation tillage, terraces, and buffer strips. In some cases, secondary containment systems, sedimentation basins, or ponds may be necessary to collect runoff. More than one runoff-control practice may be necessary for protection in areas with high runoff potential. Soil properties, including infiltration, may be improved by manure application. The method, rate and timing of manure application should be considered to reduce environmental impacts. The transport of nutrients and pathogens by overland flow is influenced by manure characteristics, loading rates, incorporation, and the time between manure addition and the first rainfall. Through proper management, manure can serve as a valuable nutrient source and soil amendment without causing environmental concerns.

A win-win saving situation Conservation tillage systems affect infiltration rates by increasing crop residue and soil organic matter at the soil surface. In addition to other irrigation conservation measures, conservation tillage systems can save water by increasing the infiltration rate and water holding capacity, providing good stewardship of both soil and water resources.

Cotton, the crop that for over 150 years defined both the culture and economy of the South, has once again returned to the region after decades of decline. In 1995, the state of Georgia recorded a monumental harvest of nearly 2 million bales, the largest output in the state since 1918. Predictions for 1996 call for an even greater cotton harvest. Cotton once again has become a prominent crop in Georgia and throughout the South. Increase in cotton production can be attributed to high prices, increased demand, worldwide shortages, and eradication of the boll weevil. Whether this growth is merely a cyclical response to changing global conditions or represents a significant structural change remains to be seen, but there is no doubt that cotton—once the region's dominant crop—has returned to prominence in Georgia and in the South.