Monitoring of soil biochemical quality parameters under greenhouse spinach cultivation through animal waste recycling

Under the intensive agricultural system, direct application of animal slurries to soils can provide a sustainable disposal of these wastes by inducing positive changes in soil quality and fertility. However, how animal wastes quantitatively affect the key nutrients (C, N, P and S) transforming soil enzymes is not clearly known. A greenhouse spinach cultivation study demonstrated that pig slurry, either in raw (RS) or processed (aerobically aged) (PS) form, significantly (p?β-glucosidase (23–39%), urease (59–103%), nitrate reductase (73–103%) and dehydrogenase (27–72%)) and microbial growth in soil as compared to the unamended control. However, it did not significantly (p?>?.05) alter the aryl sulphatase enzyme activity. Slurry applications also significantly improved the macro (N, P and K) and micronutrients (Cu, Mn, Zn and Fe) uptake by spinach plant and hence the yield (2.9–3.38 times higher than control). Similarly, compared to chemical fertilisers the application of pig slurries improved soil biological and biochemical parameters as well as plant nutrients uptake. This study demonstrated the closing of global energy and nutrient cycles through land application of animal wastes without compromising the crop yield.     

Design and use of group-specific primers and probes for real-time quantitative PCR

Real-time quantitative polymerase chain reaction (qPCR) has gained popularity as a technique to detect and quantify a specific group of target microorganisms from various environmental samples including soil, water, sediments, and sludge. Although qPCR is a very useful technique for nucleic acid quantification, accurately quantifying the target microbial group strongly depends on the quality of the primer and probe used. Many aspects of conducting qPCR assays have become increasingly routine and automated; however, one of the most important aspects, designing and selecting primer and probe sets, is often a somewhat arcane process. In many cases, failed or non-specific amplification can be attributed to improperly designed primer-probe sets. This paper is intended to provide guidelines and general principles for designing group-specific primers and probes for qPCR assays. We demonstrate the effectiveness of these guidelines by reviewing the use of qPCR to study anaerobic processes and biologic nutrient removal processes. qPCR assays using group-specific primers and probes designed with this method, have been used to successfully quantify 16S ribosomal Ribonucleic Acid (16S rRNA) gene copy numbers from target methanogenic and ammonia-oxidizing bacteria in various laboratory- and full-scale biologic processes. Researchers with a good command of primer and probe design can use qPCR as a valuable tool to study biodiversity and to develop more efficient control strategies for biologic processes.     

Evaluation of the potential methane yield of industrial wastewaters used in bioreactor landfills

To increase the moisture content of waste disposed in a bioreactor landfill, it is critical to secure the moisture source. In this study, industrial wastewater was evaluated as a potential moisture source for a bioreactor landfill with respect to the impact on methane generation. Industrial wastewater samples were collected from fishery, brewery and dairy industries. These samples were tested for basic water chemistry parameters, heavy metals, and methane generation using the regular and modified biochemical methane potential (BMP) assays. Despite high sodium and total phosphate concentrations in the fishery wastewater, a significant methane yield was observed (0.313?m³ CH₄/kg COD). However, a relatively large amount of fishery wastewater added at the phase of methane generation acceleration adversely affected microbial activity. Samples from the brewery and dairy wastewater did not indicate significant inhibitory effects on methane generation in either the regular or the modified BMP assay. This study demonstrates the utility of wastewater as an alternative to traditional moisture sources when used to enhance methane production in a bioreactor landfill.     

Effect of acute whole-body proton irradiation on hematological and intestinal variables in mice

Female C57BL/6 mice were exposed to a single dose of protons or ⁶⁰Co gamma rays at 20 mGy and 2 Gy, which represent the recommended limit for annual occupational exposure and the daily fractional dose for patients undergoing radiotherapy, respectively. A control group was not exposed to radiation. The number of peripheral blood, bone marrow, and spleen cells was assessed 24 h after radiation to investigate the marrow suppression. The number of lymphocytes and neutrophils in peripheral blood was significantly lower in mice exposed to the higher dose of radiation than in the nonirradiated mice. However, at a low dose of radiation, there were no discernable hematological effects. The frequency of micronuclei in bone marrow cells was increased only after the high dose of gamma radiation. Radiation-induced intestinal apoptosis was measured using terminal deoxynucleotide transferase labeling assay. The magnitude of damage was greater after gamma irradiation than after proton irradiation at the same dose. Among the systemic biological end point to predict whole body radiation effect, the apoptosis of intestinal crypts may be the most sensitive parameter to provide information even at low dose of radiation.     

Efficacy of rapeseed residue and eggshell waste on enzyme activity and soil quality in rice paddy

Addition of plant residue into soils improves soil physiochemical properties and its fertility. Rapeseed residue is an emerging N source to paddy soils via rice-rape double-cropping practice. The objective of this study was to evaluate the effects of rapeseed residue and eggshell waste on chemical changes and enzyme activity in the rice paddy soil. The powdered eggshells at 0, 1, 3, and 5% were applied once to 7.0 kg paddy repacked soils in each pot treated with the rapeseed residue or the conventional N, P, and K fertilisers. Eight rice seedlings (Oriza sativa L. cv. Ilmibyeo) (40 days after sowing) were transplanted to the treated each pot. The contents of total C (TC) and N (TN), and organic matter (OM) were significantly increased in soils treated with the rapeseed residue compared to the N, P, and K fertilisers. With the addition of eggshell containing ～92% CaCO₃, a considerable increase of soil pH was observed in soils treated with the rapeseed residue and the N, P, and K fertilisers, compared to the untreated soil. Activities of β-glucosidase, urease, and arylsulfatase enzymes were higher in soils treated with the rapeseed residue than soils treated with the N, P, and K fertilisers. The eggshell additions at 1, 3, and 5% into soils treated with the rapeseed residue increased enzyme activity mainly resulting from N mineralisation, whereas no change in enzyme activity was observed in the soils treated with the NPK fertiliser. The combined use of the rapeseed residue and the eggshells can be beneficial to improve soil environment.     

Improving vulnerability assessment towards Integrated Coastal Zone Management (ICZM): a case study of small islands in Indonesia

Vulnerability assessment is one of the methods currently being used to measure the ocean and coastal sustainability in order to enable better evaluation and redesign of land-based development and policy-making. Because of different geological and geographical formations, the elements that comprise the vulnerability indicators are different from each other, and there are various vulnerability equations that have been used. At the present time, there are no unified vulnerability indicators that can be applied universally to every country. The Seribu Islands, Indonesia, also known in English as the Thousand Islands, consisting of 105 islands located to the north of Jakarta, have been chosen as a study area for vulnerability assessment according to the basic principles of Integrated Coastal Zone Management theory. The results indicate that in practice, Indonesian Integrated Coastal Zone Management legal systems do exist and that in some cases, part of the responsibility for the problems rests with legislation that imposes complex systems of administration, unrealistic sanctions and impractical solutions. This research also shows that inter-sectoral, inter-governance and spatial developments are the three components that need to be improved for the successful implementation of Integrated Coastal Zone Management in the region.     

The role of black carbon as a catalyst for environmental redox transformation

Black carbon (BC) is an important class of geosorbents that control the fate and transport of organic pollutants in soil and sediment. We previously demonstrated a new role of BC as an electron transfer mediator in the abiotic reduction of nitroaromatic and nitramine compounds by Oh and Chiu (Environ Sci Technol 43:6983–6988, 2009). We proposed that BC can catalyze the reduction of nitro compounds because it contains microscopic graphitic (graphene) domains, which facilitate both sorption and electron transfer. In this study, we assessed the ability of different types of BC—graphite, activated carbon, and diesel soot—to mediate the reduction of 2,4-dinitrotoluene (DNT) and 2,4-dibromophenol (DBP) by H₂S. All three types of BC enhanced DNT and DBP reduction. H₂S supported BC-mediated reduction, as was observed previously with a thiol reductant. The results suggest that BC may influence the fate of organic pollutants in reducing subsurface environments through redox transformation in addition to sorption.     

A New Flood Index for Use in Evaluation of Local Flood Severity: A Case Study of Small Ungauged Catchments in Korea1

Ahn, Jae Hyun and Hyun Il Choi, 2013. A New Flood Index for Use in Evaluation of Local Flood Severity: A Case Study of Small Ungauged Catchments in Korea. Journal of the American Water Resources Association (JAWRA) 49(1): 1‐14. DOI: 10.1111/jawr.12025 Abstract: The aim of this article is to develop a new index measuring the severity of floods in small ungauged catchments for initial local flood information by the regression analysis between the new flooding index and rainfall patterns. Although a rapid local flood caused by heavy storm in a short period of time is now one of common natural disasters worldwide, such a sudden and violent hydrologic event is difficult to forecast. As local flooding rises rapidly with little or no advance warning, the key to local flood forecasting is to quickly identify when and where local flooding above a threshold is likely to occur. The new flooding index to characterize local floods is measured by the three normalized relative severity factors for the flood magnitude ratio, the rising curve gradient, and the flooding duration time, quantifying characteristics of flood runoff hydrographs. The new flooding index implemented for the two selected small ungauged catchments in the Korean Peninsula shows a very high correlation with logarithm of the 2‐h maximum rainfall depth. This study proposes 30 mm of rainfall in a 2‐h period as a basin‐specific guidance of precaution for the incipient local flooding in the two study catchments. It is expected that the best‐fit regression equation between the new flooding index and a certain rainfall rate can provide preliminary observations, the flood threshold, and severity information, for use in a local flood alert system in small ungauged catchments. Editor's note: This paper is part of a featured series on Korean Hydrology. The series addresses the need for a new paradigm of river and watershed management for Korea due to climate and land use changes.     

Effects of the simultaneous application of potassium and calcium on the soil-to-Chinese cabbage transfer of radiocesium and radiostrontium

Pot experiments were carried out in a greenhouse to investigate how effectively the transfer of radiocesium and radiostrontium from soil to Chinese cabbage could be reduced by applying K and Ca simultaneously to the soil. The sources of these elements were KCl and Ca(OH)(2) at agrochemical grades. Varying dosages of K and Ca were tested for an acid loamy soil treated with a mixed solution of (137)Cs and (85)Sr at two different times - 3 d before sowing and 32 d after sowing. For the pre-sowing deposition, the soil-to-plant transfer of (137)Cs decreased sharply with increasing dosages of K and Ca (K/Ca, g m(-2)) from 4.8/46 up to 22.4/215 but the (85)Sr transfer had the greatest reduction at a dosage of 12.8/123. At this dosage, an about 60% reduction occurred for each radionuclide. Plant growth was inhibited from the dosage of 22.4/215, above which all the plants died young. Both dosages of 4.8/46 and 12.8/123 tested following the growing-time deposition produced around 95% reductions for (137)Cs and 50% reductions for (85)Sr. In the second year after the 12.8/123 applications, the effects for (85)Sr were almost the same as in the first year, whereas those for (137)Cs were diminished slightly for the pre-sowing deposition and markedly for the growing-time deposition. Considerably (K) or slightly (Ca) higher doses than 12.8/123 would be allowable for the maximum TF reductions achievable without a growth inhibition.     

Predictive model for the (14)C radioactivity in a plant following an exposure to airborne (14)CO(2) gas

This paper provides details of a dynamic compartment model for estimating the (14)C radioactivity in an agricultural plant exposed to an amount of airborne (14)CO(2) gas. The plant, in the model, is divided into two compartments, the plant body (shoot and root) and ears, to predict the radioactivity of different parts of a plant. The carbon transports from, to and between the compartments are described by the processes of a photosynthesis, respiration, and translocation. The carbon transport fluxes of these processes are determined from the growth rates of a plant, which are usually easily attained. The model predictions showed that the present model could converge to a region where the specific activity model is applicable when the elapsed exposure time was extended up to the harvest time of a plant. The (14)C activity of a plant was greatly affected by the elapsed exposure time, the developmental stages of a plant at an exposure time, and the airborne (14)C activity during an exposure. It was expected that the peak of the ears' (14)C activity appeared when the exposure time was close to the ears-maturity date. The model predictions agreed reasonably well with the measured (14)C radioactivity of the rice plants that were artificially exposed to (14)CO(2) of a high (14)C source for a short period of time in an exposure box.