Search Results - (Author, Cooperation:M. L. Thompson)

2013-10-26

American Association for the Advancement of Science (AAAS)

0036-8075

1095-9203

Biology

Chemistry and Pharmacology

Computer Science

Medicine

Natural Sciences in General

Physics

Animals ; Benzimidazoles/chemistry/*pharmacology ; Caenorhabditis elegans ; Cells, Cultured ; *Cytoprotection ; Drug Evaluation, Preclinical ; Endosomal Sorting Complexes Required for Transport/*genetics ; Gene Regulatory Networks/*drug effects ; Neurodegenerative Diseases/*metabolism ; Neurons/*drug effects/metabolism ; Neuroprotective Agents/*pharmacology ; Parkinson Disease/metabolism ; Rats ; Saccharomyces cerevisiae/drug effects ; Saccharomyces cerevisiae Proteins/*genetics ; Small Molecule Libraries/chemistry/pharmacology ; Ubiquitin-Protein Ligase Complexes/*genetics ; Ubiquitin-Protein Ligases/*genetics ; alpha-Synuclein/*metabolism

2018-01-25

National Academy of Sciences

0027-8424

1091-6490

Biology

Medicine

Natural Sciences in General

1573-0662

Carbon dioxide ; interannual variations ; Southern Oscillation ; El Nino

Springer Online Journal Archives 1860-2000

Chemistry and Pharmacology

Geosciences

Abstract A method is described for the analysis of the interannual variability of background atmospheric carbon dioxide concentration. The analysis is carried out on the data from 6 observatories for which records of 〉8 years were available. A global-scale interannual variation of CO2 concentration in the troposphere with a characteristic time-scale of 2–3 years has been confirmed throughout the period of the records. These variations are estimated to be associated with carbon cycle imbalances of 2–3 Gt or annual net exchanges between the atmosphere and another carbon reservoir(s) at a rate of about 1.2 Gt of carbon per year. Lag correlations and amplitude comparisons between the records suggests a low latitude southern hemisphere origin to this phenomenon. The interannual variations of CO2 increase are found to be correlated with those observed in data for Pacific sea surface temperatures and Pacific witd stress, the Southern Oscillation Index and the Quasi-Biennial Oscillation. However multiple regression studies found that once the Southern Oscillation index is used as an explanatory variable for CO2 variations, the inclusion of additional geophysical variables does not give any significant improvement in the regression.

Electronic Resource

1572-9680

filter strip ; NPS pollution ; constructed wetland ; soil bioengineering ; best management practice

Springer Online Journal Archives 1860-2000

Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

Abstract A multi-species riparian buffer strip (MSRBS) system was designed and placed along a Central Iowa stream in 1990. Bear Creek, is typical of many streams in Central Iowa where the primary land use along the stream's length is row crop (corn and soybeans) production agriculture or intensive riparian zone grazing. The Bear Creek watershed is long (∼ 35 km), narrow (3–6 km), and drains 7,661 ha of farmland. The MSRBS system is a 20 m wide filter strip consisting of four or five rows of fast-growing trees planted closest to the stream, then two shrub rows, and finally a 7 m wide strip of switchgrass established next to the agricultural fields. The 1.0 km long system, is located on an operational farm and is laid out in a split block design on both sides of Bear Creek. An integral part of this system is a streambank stabilization soil bioengineering component and a constructed wetland to intercept NPS pollutants in field drainage tile water flow. It is hypothesized that this system will function effectively as a nutrient, pesticide, and sediment sink for NPS pollutants coming from the upslope agricultural fields. Prior to establishment of the MSRBS system, the riparian zone along Bear Creek was grazed and row cropped to the stream edge. Since 1990 there has been dramatic alteration in the appearance and functioning of this riparian zone. After four growing seasons, the fast-growing tree species (cottonwood, silver maple, willow, and green ash) range in height from 2.4 m to over 5.5 m. Mean (four-year) biomass production of silver maple was 8.4 dry Mg ha−1, more than twice to seven times the yield from other silver maple research plots in Central Iowa. The shrub species, selected because of desired wildlife benefits, have done well in terms of survival and growth with ninebark, Nannyberry viburnum and Nanking cherry doing the best. The switchgrass grass has developed into a dense stand that effectively stops concentrated flow from the agriculture fields and allows for infiltration rates well above the field rate. Early root biomass data indicate significantly more roots below the MSRBS than agricultural fields. This suggests better soil stabilization, absorption of infiltrated water, and soil-root-microbe-NPS pollutant interaction characteristics within the MSRBS system than the cropped fields. Nitrate-nitrogen concentrations in the MSRBS never exceed 2 mg l−1 whereas the levels in the adjacent agricultural fields exceed 12 mg l−1. The water quality data collected suggest that the MSRBS is effective in reducing NPS pollutants in the vadose and saturated zone below the system. The soil bioengineering revetments have stabilized the streambank and minimized bank collapse. Initial results (from 4 months of operation) from the constructed wetland (built in summer 1994) indicate nitrate-nitrogen concentrations of the tile inflow water 〉15 mg l−1 whereas, the outflow water had a nitrate-nitrogen concentration of 〈3 mg l−1. Over time this wetland should become more effective in removing excess nitrogen moving with the tile flow from the agricultural fields because of the accumulation of organic matter from the cattails. Overall the MSRBS system seems to be functioning as expected. This MSRBS system offers farmers a way to intercept eroding soil, trap and transform NPS pollution, stabilize streambanks, provide wildlife habitat, produce biomass for on-farm use, produce high-quality hardwood in the future, and enhance the aesthetics of the agroecosystem. As a streamside best management practice (BMP), the MSRBS system complements upland BMPs and provides many valuable private and public market and non-market benefits.

Electronic Resource