Search Results - (Author, Cooperation:S. Miao)

2018-11-03

American Association for the Advancement of Science (AAAS)

2375-2548

Natural Sciences in General

2016-03-05

American Association for the Advancement of Science (AAAS)

0036-8075

1095-9203

Biology

Chemistry and Pharmacology

Computer Science

Medicine

Natural Sciences in General

Physics

1526-100X

Blackwell Publishing Journal Backfiles 1879-2005

Biology

Understanding Cladium jamaicense (sawgrass) seedling establishment is an important component of an Everglades restoration program because the degree of sawgrass recovery and concurrent Typha domingensis (cattail) decline will be used to evaluate restoration success. To understand sawgrass recovery at locations with increased soil nutrients, we tested the effects of transplanting sawgrass seedlings to pots at different densities and investigated how nutrient additions affect seedling growth. Survivorship of seedlings transplanted into moist commercial potting soil at three densities ranged from 61% to 95%. After 6 months, maximum survivorship (90%) occurred at medium densities (2–4 seedlings per pot 16 cm in diameter). Nutrient additions, totaling 6.5 N g/m2, 9.8 P g/m2, 6.5 g/m2, were applied approximately 4 months after seedlings were transplanted. The biomass of the plants receiving nutrient additions (pulsed) was significantly higher (by over 30%) than plants with no nutrient addition (control). Photosynthetic rates for nutrient-enriched plants (measured 6-weeks after the nutrient additions) were significantly greater (by 32–45%) than for control plants. Instantaneous leaf water use efficiency increased significantly (by more than 20%) in pulsed plants. The results suggest that preventing root damage is crucial for the success of trans planted sawgrass seedlings and that nutrient additions enhanced seedling growth.

Electronic Resource

1750-3841

Blackwell Publishing Journal Backfiles 1879-2005

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

Process Engineering, Biotechnology, Nutrition Technology

: Nonenzymatic browning (NEB) rates of amorphous, carbohydrate-based, freeze-dried and spray-dried food model systems containing L-lysine and D-xylose as reactants (5% w/w) were investigated at different temperatures (40 °C, 50 °C, 60 °C, 70 °C, 80 °C, 90 °C). Samples were exposed to various relative vapor pressure levels (11%, 23%, and 33%) to adjust water contents. Water sorption was determined gravimetrically, and data were modeled using the Brunauer-Emmett-Teller and Guggenheim-Anderson-deBoer equations. Glass transition, Tg, was observed by differential scanning calorimetry. NEB was followed spectrophotometrically. The surface structures of freeze-dried and spray-dried models were observed by scanning electron microscopy. The freeze-dried samples and the spray-dried samples showed different surface structures and slight differences in thermal behavior. Crystallization of component sugars in the freeze-dried samples was slightly more delayed than in spray-dried samples. The glass transition temperatures in spray-dried samples were higher than those of the freeze-dried samples at the same water activity. The temperature dependence of NEB rate in both systems followed the Arrhenius kinetics, but the activation energies were different. Williams-Landel-Ferry equation could be used to model the NEB kinetics in the freeze-dried system, but for the spray-dried system, negative constant values were not within the allowable range.

Electronic Resource

0304-3800

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Biology

Electronic Resource

0044-8486

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

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

Electronic Resource

0040-4039

Alkaloid ; Ascidian ; Trididemnum

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Chemistry and Pharmacology

Electronic Resource

0040-4039

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Chemistry and Pharmacology

Electronic Resource

0040-4020

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Chemistry and Pharmacology

Electronic Resource

1432-1939

Elevated CO2 atmospheres ; Forest productivity ; Quercus ; Betula ; Acer

Springer Online Journal Archives 1860-2000

Biology

Abstract To elucidate how enriched CO2 atmospheres, soil fertility, and light availability interact to influence the long-term growth of tree seedlings, six co-occurring members of temperate forest communities including ash (Fraxinus americana L.), gray birch (Betula populifolia), red maple (Acer rubrum), yellow birch (Betula alleghaniensis), striped maple (Acer pensylvanicum), and red oak (Quercus rubra L.) were raised in a glasshouse for three years in a complete factorial design. After three years of growth, plants growing in elevated CO2 atmospheres were generally larger than those in ambient CO2 atmospheres, however, magnitudes of CO2-induced growth enhancements were contingent on the availability of nitrogen and light, as well as species identity. For all species, magnitudes of CO2-induced growth enhancements after one year of growth were greater than after three years of growth, though species' growth enhancements over the three years declined at different rates. These results suggest that CO2-induced enhancements in forest productivity may not be sustained for long periods of time. Additionally, species' differential growth responses to elevated CO2 may indirectly influence forest productivity via long-term species compositional changes in forests.

Electronic Resource

1432-1939

Clonal integration ; Compensatory growth ; Fertilizer application ; Root removal ; Solidago canadensis

Springer Online Journal Archives 1860-2000

Biology

Summary Compensatory growth in response to simulated belowground herbivory was studied in the old-field clonal perennialSolidago canadensis. We grew rootpruned plants and plants with intact root systems in soil with or without fertilizer. For individual current shoots (aerial shoot with rhizome and roots) and for whole clones the following predictions were tested: a) root removal is compensated by increased root growth, b) fertilizer application leads to increased allocation to aboveground plant organs and increased leaf turnover, c) effects of fertilizer application are reduced in rootpruned plants. When most roots (90%) were removed current shoots quickly restored equilibrium between above-and belowground parts by compensatory belowground growth whereas the whole clone responded with reduced aboveground growth. This suggests that parts of a clone which are shared by actively growing shoots act as a buffer that can be used as source of material for compensatory growth in response to herbivory. Current shoots increased aboveground mass and whole clones reduced belowground mass in response to fertilizer application, both leading to increased allocation to aboverground parts. Also with fertilizer application both root-pruned and not root-pruned plants increased leaf and shoot turnover. Unfertilized plants, whether rootpruned or not, showed practically no aboveground growth and very little leaf and shoot turnover. Effects of root removal were as severe or more severe under conditions of high as under conditions of low nutrients, suggesting that negative effects of belowground herbivory are not ameliorated by abundant nutrients. Root removal may negate some effects of fertilizer application on the growth of current shoots and whole clones.

Electronic Resource

1432-1939

Elevated CO2 ; Moisture gradient ; Biomass ; Niche breadth ; Gray birch

Springer Online Journal Archives 1860-2000

Biology

Summary To determine the effects of elevated CO2 and soil moisture status on growth and niche characteristics of birch and maple seedlings, gray birch (Betula populifolia) and red maple (Acer rubrum) were experimentally raised along a soil moisture gradient ranging from extreme drought to flooded conditions at both ambient and elevated atmospheric CO2 levels. The magnitude of growth enhancement due to CO2 was largely contingent on soil moisture conditions, but differently so for maple than for birch seedlings. Red maple showed greatest CO2 enhancements under moderately moist soil conditions, whereas gray birch showed greatest enhancements under moderately dry soil conditions. Additionally, CO2 had a relatively greater ameliorating effect in flooded conditions for red maple than for gray birch, whereas the reverse pattern was true for these species under extreme drought conditions. For both species, elevated CO2 resulted in a reduction in niche breadths on the moisture gradient; 5% for gray birch and 23% for red maple. Species niche overlap (proportional overall) was also lower at elevated CO2 (0.98 to: 0.88: 11%). This study highlights the utility of of experiments crossing CO2 levels with gradients of other resources as effective tools for elucidating the potential consequences of elevated CO2 on species distributions and potential interactions in natural communities.

Electronic Resource

1432-1939

Global Change ; Forest regeneration ; Osmotic adjustment ; Cell wall elasticity

Springer Online Journal Archives 1860-2000

Biology

Abstract The effect of increasing atmospheric CO2 concentrations on tissue water relations was examined in Betula populifolia, a common pioneer tree species of the northeastern U.S. deciduous forests. Components of tissue water relations were estimated from pressure volume curves of tree seedlings grown in either ambient (350 μl l−1) or elevated CO2 (700 μl l−1), and both mesic and xeric water regimes. Both CO2 and water treatment had significant effects on osmotic potential at full hydration, apoplasmic fractions, and tissue elastic moduli. Under xeric conditions and ambient CO2 concentrations, plants showed a decrease in osmotic potentials of 0.15 MPa and an increase in tissue elastic moduli at full hydration of 1.5 MPa. The decrease in elasticity may enable plants to improve the soil-plant water potential gradient given a small change in water content, while lower osmotic potentials shift the zero turgor loss point to lower water potentials. Under elevated CO2, plants in xeric conditions had osmotic potentials 0.2 MPa lower than mesic plants and decreased elastic moduli at full hydration. The increase in tissue elasticity at elevated CO2 enabled the xeric plants to maintain positive turgor pressures at lower water potentials and tissue water contents. Surprisingly, the elevated CO2 plants under mesic conditions had the most inelastic tissues. We propose that this inelasticity may enable plants to generate a favorable water potential gradient from the soil to the plant despite the low stomatal conductances observed under elevated CO2 conditions.

Electronic Resource

1573-5117

Mangrove ; Kandelia candel ; seedling ; growth ; wastewater ; pollution

Springer Online Journal Archives 1860-2000

Biology

Abstract A greenhouse experiment wad performed to evaluate the effects of synthethic wastewater in three different strengths, NW, MW and CW, on the growth of the one-year old Kandelia candel (L.) Druce plants. NW had the characteristics and strength similar to natural municipal wastewater while MW and CW contained five and ten times of the nutrients and heavy metals in NW, respectively. Artificial seawater was used as the control. During one year wastewater treatment experiment, Kandelia were found to withstand wastewater of high strength and toxic symptoms were not detected in all plants. Synthethic wastewater with strength similar to the natural municipal sewage (NW) stimulated plant growth. The plants treated with NW had significantly higher aerial and root biomass, taller stem than those found in the CW, MW and the control. Maximum growth, in terms of both stem height and total biomass, of all plants occured in summer months, from June to September. With respect to the physiological and biochemical activities, CW and MW treated plants had significantly lower levels of chlorophyll a, total chlorophyl and catalase activity than those found in NW and control groups. In contrast, the proline content of plants treated with wastewater was similar to that of the control. These result suggest that normal wastewater (NW), attributed to its nutrients and trace elements, enhanced plant growth. The medium (MW) and concentrated wastewater (CW) supported similar amount of plant growth as the control but the physiological and biochemical parametes indicate that these treated plants might have been exposed to some kind of stress, probably due to the heavy metals present in MW and CW.

Electronic Resource

2018-03-06

The American Society for Microbiology (ASM)

0099-2240

1098-5336

Biology