Species Trials of Short Rotation Woody Crops on Two Wastewater Application Sites in North Carolina,USA

Forty-two Populus spp. clones, Eucalyptus benthamii, and seven tree species native to North Carolina were evaluated for survival and height growth through the establishment phase at two municipal wastewater application sites. Groundwater was monitored at each site to determine if establishment of the species trials resulted in exceedances of nutrient mitigation requirements. At the Gibson Wastewater Treatment Facility, 26 Populus clones had 100 % survival, with mean height growths ranging between 152 to 260 cm, and basal diameters ranging between 11.4 and 28.8 mm. Green ash, planted in 2011 and 2012, had high survivorship (>95 %) with first year mean height growth of 30?±?28 cm (2012) and second year mean height growth of 101?±?52 cm (2011). Basal diameter for green ash was 33.3?±?12.6 mm. E. benthamii had moderate survivorship (>77 %) and first year mean height growth of 47?±?27 cm. At the Jacksonville Wastewater Treatment Facility, green ash and bald cypress had high survivorship (>96 %), first year mean height growths of 14?±?25 cm and 27?±?16 cm, and basal diameters of 13.1?±?3.9 mm and 11.6?±?4.8 mm, respectively. Survivorship for 12 Populus clones ranged from 50 and 94 % with mean first year height growths between 58 to 121 cm, and basal diameters between 6.8 and 12.5 mm. E. benthamii had low survivorship (43 %) with mean first year height growths of 17?±?17 cm and basal diameters of 12.0?±?7.7 mm. Groundwater concentrations of NO₃?+?NO₂ and N-NH₄ remained below regulatory requirements at both sites with one exceedance in February 2012 in Jacksonville, NC. The results show that some Populus clones are excellent candidates for woody biomass production on municipal wastewater application fields. Native green ash and bald cypress are also good candidates, but these trees may require longer rotations than Populus to achieve similar biomass yields.     

Repopulation techniques for Macrocystis integrifolia (Phaeophyceae: Laminariales) in Atacama,Chile

The giant kelp Macrocystis (integrifolia) has been intensely harvested in northern Chile for several years. In order to prevent a future disaster, we developed two different techniques for restoration of damaged Macrocystis integrifolia beds in the Atacama region of Chile. (1) Explantation: Laboratory-grown juvenile sporophytes were fixed to different substrata (plastic grids, ceramic plates, or boulders) by elastic bands or fast-drying glue (cyanoacrylate). Explants reached 150–200 cm in length within 5 months (relative growth rate?≈?1.3–1.7 % day^?1), and reproductive maturity in 5–7 months. (2) Seeding of spores: Mature sporophylls were placed at 8 m depth on the sea bottom, supported by cotton gauze sleeves attached to boulders of different origin. Sixty percent of clean boulders collected on the beach produced up to seven recruits per boulder. In contrast, 20 % of the boulders from the sea bottom, colonized by epibionts, showed up to two recruits. Relative growth rates, however, were similar (≈2.4–2.6 % day^?1). Practical applications of our findings are: laboratory-produced juvenile sporophytes fixed to various substrata by elastic bands or cyanoacrylate glue can be used to colonize rocks or artificial reefs. In cases, where laboratory-grown seedlings are unavailable, mature sporophylls from nearby Macrocystis beds can be used to establish new recruits on rocky substrata.     

Latent pulmonary hypertension in atrial septal defect: Dynamic stress echocardiography reveals unapparent pulmonary hypertension and confirms rapid normalisation after ASD closure

Objective

Closure of atrial septal defects (ASD) prevents pulmonary hypertension, right heart failure and thromboembolic stroke. The exact timing for ASD closure is controversial.

Methods

In a prospective study to address the question whether unapparent pulmonary hypertension can be revealed prior to right ventricular (RV) remodelling, patients were investigated before and 6, 12, and 24 months after ASD closure using exercise stress echocardiography (ESE) and ergospirometry (n?=?24).

Results

At rest, RV systolic pressure (RVSP) was normal in 58.8 %, slightly elevated in 26.5 %, and moderately elevated in 11.8 %. One patient showed severe pulmonary hypertension. During ESE, all patients with normal RVSP at rest exhibited an increase (25.7?±?1.2 mmHg vs. 45.3?±?2.3 mmHg, p?<?0.001). After closure the RVSP was lower, both at rest and ESE. RV diameters decreased too. Tricuspid annulus plane systolic excursion (TAPSE) at rest remained lower after closure (24.0?±?0.9 vs. 22.0?±?0.9 mm, p?<?0.05). TAPSE in ESE was elevated, and stayed stable after closure (30.1?±?1.8 mm vs. 29.3?±?1.6 mm). Before closure, RV systolic tissue velocities (s^a) at rest were normal and decreased after closure (14.0?±?1.0 cm/s vs. 11.5?±?0.7 (6 month) vs. 10.6?±?0.5 cm/s (12 month), p?<?0.05). During ESE, s^a velocity was similar before and after closure (23.0?±?1.3 cm/s vs. 23.3?±?1.9 cm/s). Maximal oxygen uptake (VO₂/kg) did not differ between baseline and follow-ups.

Conclusion

Latent pulmonary hypertension may become apparent in ESE. ASD closure leads to a significant reduction in this stress-induced pulmonary hypertension and to a decrease in the right heart diameters indicating reverse RV remodelling. RV functional parameters at rest did not improve. The VO₂/kg did not change after ASD closure.     

Changes in bacterial CO2 fixation with depth in agricultural soils

Soils were incubated continuously in an atmosphere of ¹⁴CO₂ and the distribution of labeled C into soil organic carbon (¹⁴C-SOC) was determined at 0–1, 1–5, and 5–17 cm down the profile. Significant amounts of ¹⁴C-SOC were measured in paddy soils with a mean of 1,180.6?±?105.2 mg kg^–1 at 0–1 cm and 135.3?±?47.1 mg kg^?1 at 1–5 cm. This accounted for 5.9?±?0.7 % and 0.7?±?0.2 %, respectively, of the total soil organic carbon at these depths. In the upland soils, the mean ¹⁴C-SOC concentrations were 43 times (0–1 cm) and 11 times (1–5 cm) lower, respectively, than those in the paddy soils. The amounts of ¹⁴C incorporated into the microbial biomass (MBC) were also much lower in upland soils (5.0?±?3.6 % and 2.9?±?1.9 % at 0–1 and 1–5 cm, respectively) than in paddy soils (34.1?±?12.4 % and 10.2?±?2.1 % at 0–1 and 1–5 cm, respectively). Similarly, the amount of ¹⁴C incorporated into the dissolved organic carbon (DOC) was considerably higher in paddy soils (26.1?±?6.9 % and 6.9?±?1.3 % at 0–1 and 1–5 cm, respectively) than in upland soils (6.0?±?2.7 % and 4.3?±?2.2 %, respectively). The observation that the majority of the fixed ¹⁴C-SOC, RubisCO activity and cbbL gene abundance were concentrated at 0–1 cm depth and the fact that light is restricted to the top few millimeters of the soil profiles highlighted the importance of phototrophs in CO₂ fixation in surface soils. Phylogenetic analysis of the cbbL genes showed that the potential for CO₂ fixation was evident throughout the profile and distributed between both photoautotrophic and chemoautotrophic bacteria such as Rhodopseudomonas palustris, Bradyrhizobium japonicum, Rubrivivax gelatinosus and Ralstonia eutropha.     

Survival of kelp adjacent to areas grazed by sea urchins in New South Wales,Australia

Abstract The sea urchin Centrostephanus rodgersii grazes areas of reef free of large brown algae (the barrens habitat). Survival of the kelp Ecklonia radiata adjacent to patches of barrens habitat was compared to that in the centre of kelp forests (centre) and edges of forests not adjacent to patches of barrens habitat (ungrazed). Estimates of rates of instantaneous mortality for tagged plants, as described by the slope of a negative exponential model (± 95% CI) were: barrens, 0.078 ± 0.004; centre, 0.051 ± 0.004 and ungrazed edge, 0.065 ± 0.007. Survival of plants was greatest in the middle of forests and least on the margins of patches of barrens habitat. A significant proportion of mortality in the barrens and centre positions was caused by herbivorous fish. When these plants were excluded from analysis there were no significant differences in survival between the barrens and ungrazed positions. It is concluded that C. rodgersii has little impact on the abundance of Ecklonia outside sharply defined boundaries.     

AN ALTERNATE GROWTH PATTERN FOR LAMINARIA LONGICRURIS1,2

A population of Laminaria longicruris de la Pylaie was followed for a year at Bic Island, Quebec, Canada where nutrient levels in the seawater were elevated throughout the year. Tagged kelp were measured each month for growth and analyzed for alginic acid, laminaran, mannitol, carbon, nitrogen, and nitrate. Maximum growth (3.5 cm · d^?1) was observed in June, and minimal growth (0.18 cm · d^?1) from December to February, when ice cover limited light levels. No reserves of carbon or nitrate were formed. Laminaran levels remained below 2.7% dry weight while tissue nitrate did not exceed 0.75 μmol · g^?1 dry weight. Total carbon produced per plant was 40 g C · yr^?1. Nutrient availability enables the kelp to take advantage of summer light and temperature conditions to grow rapidly.     

Tree Species Composition, Structure, and Aboveground Wood Biomass of a Riparian Forest of the Lower Miranda River, Southern Pantanal, Brazil

The aboveground wood biomass (AWB) of tropical forests plays an important role in the global carbon cycle, and local AWB estimates provide essential data that enable the extrapolation of biomass stocks to ecosystem or biome-wide carbon cycle modelling. Few AWB estimates exist in Neotropical freshwater floodplains, where tree species distribution and forest structure depend on the height and duration of periodic inundations. We investigated tree species composition, forest structure, wood specific gravity, and AWB of trees ≥10 cm dbh in 16 plots totalling an area of 1 ha in a seasonally inundated riparian forest of the lower Miranda River, southern Pantanal, Brazil. The 443 tree individuals belonged to 46 species. Four species (Inga vera, Ocotea suaveolens, Tabebuia heptaphylla and Cecropia pachystachya) comprised more than 50% of the Total Importance Values (TIV), and floristic similarities between the plots averaged 38%. Although we detected an overall increase in species diversity correlated with decreasing flood levels, the most important tree species had almost identical distribution patterns along the flooding gradient. The stand basal area per plot (±?s.d.) amounted to 3.0?±?1.1 m² (47.8?±?18.1 m²/ha), and the tree heights averaged 10.9?±?1.4 m. Multiplying the individual basal areas by individual tree heights and a form factor of 0.6, we estimated the aboveground wood volume (AWV) for each individual, and for each plot (24.4?±?11.7 m³, 391.1?±?188 m³/ha). Wood specific gravity (SG) varied between 0.39 g/cm³ (Cecropia pachystachya) and 0.87 g/cm³ (Tabebuia heptaphylla), with a stand level average of 0.63?±?0.12 g/cm³. Multiplying the individual AWV with species SG, we estimated the plot AWB to be 16.2?±?6.4 Mg (259.4?±?102 Mg/ha). This value is comparable to that reported for late-successional forest stands of Amazonian floodplain forests, and it is close to the worldwide tropical average AWB. Because tree heights in the present forest were comparatively low when compared to other Neotropical forests, we found that resprouting of stems accounted for comparatively high basal areas. We argue that stem resprouting is an adaptation of tree species originating in non-flooded Cerrado to the seasonal inundations of riparian forests.     

Comparing soil carbon sequestration in coastal freshwater wetlands with various geomorphic features and plant communities in Veracruz,Mexico

Background and aims

Wetlands are important carbon sinks across the planet. However, soil carbon sequestration in tropical freshwater wetlands has been studied less than its counterpart in temperate wetlands. We compared carbon stocks and carbon sequestration in freshwater wetlands with various geomorphic features (estuarine, perilacustrine and depressional) and various plant communities (marshes and swamps) on the tropical coastal plain of the Gulf of Mexico in the state of Veracruz, Mexico. These swamps are dominated by Ficus insipida, Pachira aquatic and Annona glabra and the marshes by Typha domingensis, Thalia geniculata, Cyperus giganteus, and Pontederia sagittata.

Methods

The soil carbon concentration and bulk density were measured every 2 cm along 80 cm soil profiles in five swamps and five marshes. Short-term sediment accretion rates were measured during a year using horizontal makers in three of the five swamps and marshes, the carbon sequestration was calculated using the accretion rates, and the bulk density and the percentage of organic carbon in the surficial layer was measured.

Results

The average carbon concentration ranged from 50 to 150 gC kg^?1 in the marshes and 50 to 225 gC kg^?1 in the swamps. When the wetlands were grouped according to their geomorphic features, no significant differences in the carbon stock (P?=?0.095) were found (estuarine (25.50?±?2.26 kgC m^?2), perilacustrine (28.33?±?2.74 kgC m^?2) and depressional wetlands (34.93?±?4.56 kgC m^?2)). However, the carbon stock was significantly higher (P?=?0.030) in the swamps (34.96?±?1.3 kgC m^?2) than in the marshes (25.85?±?1.19 kgC m^?2). The average sediment accretion rates were 1.55?±?0.09 cm yr^?1 in the swamps and 0.84?±?0.02 cm yr^?1 in the marshes with significant differences (P?=?0.040). The rate of carbon sequestration was higher (P?=?0.001) in swamp soils (0.92?±?0.12 kgC m^?2 yr^?1) than marsh soils (0.31?±?0.08 kgC m^?2 yr^?1). Differences in the rates of carbon sequestration associated with geomorphic features were found between the swamp ecosystems (P?<?0.05); i.e., higher values were found in the swamps than in the marshes in perilacustrine and estuarine wetlands (P?<?0.05). However, no significant differences (P?=?0.324) in carbon sequestration rates were found between the marsh and swamp areas of the depressional site.

Conclusions

Swamp soils are more important contributors to the carbon stock and sequestration than are marsh soils, resulting in a reduction in global warming, which suggests that the plant community is an important factor that needs to be considered in global carbon budgets and projects of restoration and conservation of wetlands.     

Ecosystem respiration derived from 222Rn measurements on Rishiri Island, Japan

We evaluated the nighttime CO₂ flux (ecosystem respiration) on Rishiri Island, located at the northern tip of Hokkaido, Japan, from 2009 to 2011, by using the relationship between atmospheric ²²²Rn and CO₂ concentrations. The annual mean CO₂ flux was 1.8 μmol m^?2 s^?1, with a maximum monthly mean in July (4.6 ± 2.6 μmol m^?2 s^?1) and a broad minimum from December to March (0.33 ± 0.29 μmol m^?2 s^?1). The annual mean was comparable to fluxes at the JapanFlux sites in northern Japan. During the season of snow cover (mid-December to early April), the CO₂ flux was low (0.45 ± 0.43 μmol m^?2 s^?1). Total annual respiration was estimated at 679 ± 174 g cm^?2, about 8 % of which occurred during the season of snow cover.     

The Influences of Chromium Supplementation on Glycemic Control,Markers of Cardio-Metabolic Risk,and Oxidative Stress in Infertile Polycystic ovary Syndrome Women Candidate for In vitro Fertilization: a Randomized,Double-Blind,Placebo-Controlled Trial

This study was carried out to investigate the effects of chromium intake on glycemic control, markers of cardio-metabolic risk, and oxidative stress in infertile polycystic ovary syndrome (PCOS) women candidate for in vitro fertilization (IVF). This randomized double-blind, placebo-controlled trial was done among 40 subjects with infertile PCOS candidate for IVF, aged 18–40 years old. Individuals were randomly allocated into two groups to take either 200 μg/day of chromium (n?=?20) or placebo (n?=?20) for 8 weeks. Biochemical parameters were assessed at baseline and at end-of-trial. Compared with the placebo, taking chromium supplements led to significant reductions in fasting plasma glucose (??2.3?±?5.7 vs. +?0.9?±?3.1 mg/dL, P?=?0.03), insulin levels (??1.4?±?2.1 vs. +?0.4?±?1.7 μIU/mL, P?=?0.004), homeostatic model of assessment for insulin resistance (??0.3?±?0.5 vs. +?0.1?±?0.4, P?=?0.005), and a significant increase in quantitative insulin sensitivity check index (+?0.004?±?0.008 vs. ??0.001?±?0.008, P?=?0.03). In addition, chromium supplementation significantly decreased serum triglycerides (??19.2?±?33.8 vs. +?8.3?±?21.7 mg/dL, P?=?0.004), VLDL- (??3.8?±?6.8 vs. +?1.7?±?4.3 mg/dL, P?=?0.004) and total cholesterol concentrations (??15.3?±?26.2 vs. ??0.6?±?15.9 mg/dL, P?=?0.03) compared with the placebo. Additionally, taking chromium supplements was associated with a significant increase in plasma total antioxidant capacity (+?153.9?±?46.1 vs. ??7.8?±?43.9 mmol/L, P?<?0.001) and a significant reduction in malondialdehyde values (?0.3?±?0.3 vs. +?0.1?±?0.2 μmol/L, P?=?0.001) compared with the placebo. Overall, our study supported that chromium administration for 8 weeks to infertile PCOS women candidate for IVF had beneficial impacts on glycemic control, few variables of cardio-metabolic risk, and oxidative stress.     

Effect of Mg, Si, and Sr on growth and antioxidant activity of the marine microalga Tetraselmis suecica

Efforts to increase the productivity of microalgal cultures have been focused on the improvement of photobioreactors, but little attention has been paid to the nutritional requirements of microalgae in order to improve culture media formulation. In this study, the main goal was obtaining a high productivity for Tetraselmis suecica (Chlorophyta) in semicontinuous culture by adding magnesium (Mg), silicon (Si), and strontium (Sr) at concentrations from 0.01 to 10 mM; at the time, the effect on steady-state cell density, biochemical composition, and antioxidant activity of T. suecica was evaluated. Because productivity is higher in high-density cultures, the work was focused many times to cell density. Mg (3 mM) and Sr (0.1 mM) added separately reached the highest steady-state cell density (7.0?×?10⁶?±?0.4 cells mL^?1) in comparison to control (4.2?±?0.1 cells mL^?1), but simultaneous addition had a synergic effect, achieving 8.7?×?10⁶?±?0.6 cells mL^?1. Silicon (3 mM) significantly affected the steady-state cell density, reaching 6.0?±?0.3 cells mL^?1 and increased the cell ash-free dry weight, reaching 127?±?7.9 pg cell^?1 in comparison to control (102.7?±?5.0 pg cell^?1), resulting in an ash-free dry weight productivity of 0.75?±?0.07 g?L^?1 day^?1. The highest fatty acids content and antioxidant activity, measured by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) method were obtained with Sr 10 mM. Sr treatments showed a high correlation (R ²?=?0.98) between DPPH inhibition and polyphenolic content, explaining its high antioxidant activity. Therefore, the addition of Mg, Si, and Sr to culture medium of T. suecica is recommended to achieve high steady-state cell density in semicontinuous cultures.     

Ulva lactuca and U. flexuosa (Chlorophyta,Ulvophyceae) cultivation in Brazilian tropical waters: recruitment,growth, and ulvan yield

Ulva spp. are used in a wide range of commercial applications, including bioremediation, food, bioenergy, pharmaceuticals, and agriculture. The sulfated polysaccharide ulvan obtained from Ulva spp. is of interest for triggering plant defenses against disease. However, the cultivation of Ulva spp. is still in its infancy. This study verified the feasibility of cultivating Ulva lactuca and Ulva flexuosa at two sites on the tropical Brazilian coast. We investigated the following: (a) methods to induce sporulation, (b) comparison of seeding ropes inoculated in vitro versus seeding at sea over 40 days, (c) production and harvest cycles at 15 and 30 days, (d) growth productivity of U. flexuosa at sea and in outdoor tanks, and (e) comparison of ulvan yields from biomass cultivated in tanks and the sea. High nutrient treatment was the most efficient method to induce sporulation (7,540?±?3,133 spores m^?1). Sea-based cultivation of U. flexuosa was only successful at one site. Seeding of ropes in vitro was more efficient than seeding at sea (0.31?±?0.20 g m^?2 day^?1), and 15-day harvest cycles were most efficient (20.1?±?1.8 % day^?1; 0.46?±?0.11 g m^?2 day^?1). Despite differences in plant growth in tanks (27.9?±?4.4 % day^?1) and at sea (20.1?±?1.8 % day^?1), the dry biomass and ulvan yields (17.7?±?5.0 %) did not differ between these systems. Cultivation of U. flexuosa was feasible at sea using in vitro seeding with a production cycle of 15 days in Brazilian tropical waters and tanks with high irradiance and enriched seawater.     

Comparison of RNA- and DNA-based bacterial communities in a lab-scale methane-degrading biocover

Methanotrophs must become established and active in a landfill biocover for successful methane oxidation. A lab-scale biocover with a soil mixture was operated for removal of methane and nonmethane volatile organic compounds, such as dimethyl sulfide (DMS), benzene (B), and toluene (T). The methane elimination capacity was 211?±?40 g?m^?2 d^?1 at inlet loads of 330–516 g?m^?2 d^?1. DMS, B, and T were completely removed at the bottom layer (40–50 cm) with inlet loads of 221.6?±?92.2, 99.6?±?19.5, and 23.4?±?4.9 mg m^?2 d^?1, respectively. The bacterial community was examined based on DNA and RNA using ribosomal tag pyrosequencing. Interestingly, methanotrophs comprised 80 % of the active community (RNA) while 29 % of the counterpart (DNA). Types I and II methanotrophs equally contributed to methane oxidation, and Methylobacter, Methylocaldum, and Methylocystis were dominant in both communities. The DNA vs. RNA comparison suggests that DNA-based analysis alone can lead to a significant underestimation of active members.     

Home range and habitat use of translocated endangered species,Cottus koreanus,in South Korea

The home range and characteristics of Cottus koreanus were investigated using passive integrated transponder (PIT) telemetry in the Gulji Stream, Korea, where the target species was artificially translocated. After release, tagged individuals moved up to 78?m away from the release site in search of proper habitats. The average distance moved until settlement was 17.1?m. The observed home range of settled individuals had longitudinal sections of 9.9?±?3.6?m and surface areas of 7.2?±?2.7?m². This is comparable to congeneric species that inhabit similar ecological habitats. Once individuals had settled, they rarely moved from that site except during the spring season. The typical microhabitat characteristics of the sites where the released individuals settled are: water depth of 5–10?cm, water velocity of 0.1–0.3?m?s^?1, and the size of boulders and cobbles of 10–20?cm in diameter. This study of translocated C. koreanus individuals provides detailed information about habitats that can be used for effective habitat restoration and successful translocations attempts of this species.     

Comparative Analysis of Serum Zinc, Copper, Manganese, Iron, Calcium, and Magnesium Level and Complexity of Interelement Relations in Generalized Anxiety Disorder Patients

The purpose of the study was to determine the concentration of serum trace and other essential elements of generalized anxiety disorder patients and to find out the relationship between element levels and nutritional status or socioeconomic factors. The study was conducted among 50 generalized anxiety disorder patients and 51 healthy volunteers. Patients were selected and recruited in the study with the help of a clinical psychologist by random sampling. The concentrations of serum trace elements (Zn, Cu, Mn, and Fe) and other two essential elements (Ca and Mg) were determined by graphite furnace and flame atomic absorption spectroscopy. Data were analyzed by independent t test, Pearson’s correlation analysis, regression analysis, and analysis of variance. The serum concentrations of Zn, Cu, Mn, Fe, Ca, and Mg in generalized anxiety disorder patients were 1.069?±?0.40, 1.738?±?0.544, 1.374?±?0.750, 3.203?±?2.065, 108.65?±?54.455, and 21?±?4.055 mg/L, while those were 1.292?±?0.621, 0.972?±?0.427, 0.704?±?0.527, 1.605?±?1.1855, 101.849?±?17.713, and 21.521?±?3.659 mg/L in control subjects. Significantly decreased (p?<?0.05) serum Zn concentration was found in the patient group compared to the control group while serum level of Cu, Mn, and Fe was significantly (p?<?0.05) higher, but the differences of the concentration of Ca and Mg between the patient and control groups were not significant (p?>?0.05). Socioeconomic data revealed that most of the patients were in the lower middle class group and middle-aged. Mean BMI of the control group (23.63?±?3.91 kg/m²) and the patient group (23.62?±?3.77 kg/m²) was within the normal range (18.5–25.0 kg/m²). The data obtained from different interelement relations in the generalized anxiety disorder patients and control group strongly suggest that there is a disturbance in the element homeostasis. So changes in the serum trace element level in generalized anxiety disorder patients occur independently and they may provide a prognostic tool for the diagnosis and treatment of this disease.     

Factors correlating with deterioration of giant kelp Macrocystis pyrifera (Laminariales, Heterokontophyta) in an aquarium setting

Survival of the giant kelp, Macrocystis pyrifera (Linnaeus) C. Agardh, in its natural habitat is governed by abiotic and biotic factors such as temperature, light, nutrients, current velocity, and predators. Factors affecting the survival of the alga in an aquarium setting, however, have not been investigated. The National Museum of Marine Biology and Aquarium (NMMBA), in subtropical Taiwan, is the only aquarium in the world that displays giant kelp that does not have naturally occurring specimens in nearby waters. Giant kelp displayed in aquaria often deteriorates within a 3-month period, yet the cause of this mortality is unknown. We investigated abiotic and biotic parameters affecting survival of giant kelp in aquaria over a 3-month period. The results indicated that temperature, salinity, pH, light, and nutrient concentrations did not affect giant kelp survival. However, the massive proliferation of epiphytic diatoms on kelp blades (from 7?×?10² cells cm^?2 initially to 3?×?10⁴ cells cm^?2 after 1 month) was identified as being the most likely candidate affecting survival of giant kelp in an aquarium setting. Potential factors that may stimulate epiphyte proliferation include lack of epiphytic algae control via predation, high nutrient concentrations, a weak current, and a generally stable environment.     

Habitat utilization, movement and use of groundwater seepages by larval and juvenile Black Redhorse, Moxostoma duquesnei

Black Redhorse (Moxostoma duquesnei) larval and juvenile habitat was characterized in the Grand River, Ontario from June to September 2007–2012. Similar to adult Black Redhorse and their congeners, larval Black Redhorse were most likely to be located in clean, clear, stable runs with low to moderate flow, over pebble, gravel and cobble substrate, mixed with sand. Areas (n?=?22) where 0+ Black Redhorse were observed and collected were 1.4?±?0.2 m from shore, with a mean water temperature of 22.0?±?0.5 °C, mean depth of 0.20?±?0.02 m and mean water velocity of 0.12?±?0.05 m/s. Larval and juvenile Black Redhorse occupied riffles, runs, pools and backwater areas; however, there was a strong preference for runs. Juvenile Black Redhorse moved upstream in the early evening and at night to overwintering areas in the Grand River in November when water temperature approached 5 °C. The persistence of Black Redhorse populations in the Grand River may be related to the presence of groundwater, which provides refuge from extreme temperature and poor water quality during the summer.     

Enhancement of Saccharina kelp production by nutrient supply in the Sea of Japan off southwestern Hokkaido,Japan

Apart from certain studies on Macrocystis pyrifera (Linnaeus) C. Agardh, very few in situ experimental studies on production have been carried out to verify that “bottom–up effects” (relating to nutrient supply) are more important than “top–down” effects (relating to herbivory) in temperate kelp forests. The effects of nutrient supply on recruitment and production of hatchery-raised gametophytes of Saccharina japonica, cultivated on a rope, and wild Saccharina religiosa, cultivated on a rope and on new concrete reefs placed at the sea bottom, were examined at an experimental site with artificial nutrient addition continuously from October 2008 to May 2009 and compared to kelp that was cultivated from October 2008 to May 2009 without nutrient supply, at a natural site in Tomari (Sea of Japan, southwestern Hokkaido, Japan). At both sites, sea urchins were removed for exclusion of top–down effect. At the natural site, no hatchery-raised S. japonica and wild S. religiosa grew on the rope. No wild S. religiosa grew on the porous-concrete reefs and rocks. At the nutrient-enhanced site, S. japonica and S. religiosa grew rapidly on the rope, at rates of 47.7 and 33.3 plants/10 cm length rope, respectively. S. religiosa grew on the concrete reefs at a concentration of 9.7 plants/0.3 m². At the nutrient-enhanced site, the concentrations of NH₄-N, NO₃-N, NO₂-N, and PO₄-P ranged from 35.2–173.2, 2.1–10.9, 0.3–1.5, and 0.8–2.6 μmol L^?1, respectively, being markedly higher than those at the natural site, where these nutrient concentrations were almost equal to the averages off Tomari. These results indicate that the production of Saccharina kelp is restricted by bottom–up effects (at a low nutrient concentration) in the Sea of Japan, southwestern Hokkaido. Nutrient supply would be essential for growth enhancement of Saccharina kelp production in a marine environment around Japan where, in recent times, water temperatures have increased by ca. 0.5 °C and nutrient concentrations have decreased.     

Usefulness of an aluminized polyester film for reducing heat in polyethylene calf hutches

This study determined the efficacy of a radiant barrier material used in the construction industry to moderate summer temperatures in polyethylene calf hutches. The cover consisted of a single layer of two-sided reflective aluminized polyester film with a center polyester scrim reinforcement (reflectivity?=?95 %). At each of two dairies, six hutches containing a young calf were either uncovered (control) or had reflective covers across the top and sides of the hutch, leaving the front, back, and 1.2?×?1.8-m attached outdoor wire pen exposed. Duplicate loggers mounted 20 cm above the flooring in the center of each hutch recorded interior temperature at 30-min intervals over 22 days during late August to early September. The mean daily interior peak temperatures in each of the hutches over 21 days of observation were significantly less (P?P?=?0.77) between dairies. The mean daily interior peak temperatures in each of the hutches over the warmest 10 days of observation were significantly less (P?P?相似文献   

Effects of different nitrogen, phosphorus, and iron concentrations and salinity on lipid production in newly isolated strain of the tropical green microalga, Scenedesmus dimorphus KMITL

The fatty acid composition, the effect of different concentrations of nitrogen (16.5-344 mg ?L^?1), phosphorus (9–45 mg? L^?1), iron (9–45 mg? L^?1) and salinity levels (0–20 psu) on lipid production in the green microalga Scenedesmus dimorphus KMITL, a new strain isolated from a tropical country, Thailand, were studied. The alga was isolated from a freshwater fish pond, and cultured in Chlorella medium by varying one parameter at a time. The main fatty acid composition of this strain was C16–C18 (97.52 %) fatty acids. A high lipid content was observed in conditions of 16.5 mg? L^?1-N, or 22 mg ?L^?1-P, or 45 mg ?L^?1-Fe, or 5 psu salinity, which accumulated lipids to 20.3?±?0.4, 19.4?±?0.2, 24.7?±?0.5, and 14.3?±?0.2 % of algal biomass, respectively. Increasing lipid content and lipid productivity was noted when the alga was cultured under high iron concentration and high salinity, as well as under reduced phosphorus conditions, whereas nitrogen limitation only resulted in an increased lipid content.