Primary productivity and nitrogen, carbon, and biomass distribution in a dense Myrica gale stand

1983 ◽  
Vol 61 (11) ◽  
pp. 2943-2948 ◽  
Author(s):  
Christa R. Schwintzer
Keyword(s):  
Aboveground Biomass ◽  
Male Flower ◽  
Growing Season ◽  
Reproductive Organs ◽  
Biomass Distribution ◽  
Flower Buds ◽  
Myrica Gale ◽  
Net Production ◽  
Nitrogen Contents ◽  
N Requirement

Aboveground vascular vegetation was harvested in twenty 0.25-m2 plots at the end of the growing season in a weakly minerotrophic, central Massachusetts peatland. The materials were separated by species and component and the Myrica gale fractions analyzed for N and C content. Myrica gale strongly dominated the site, contributing 66% of the total aboveground biomass and 74% of the main canopy leaf area. Its shoots had a mean density of 69 stems m−2 and mean height of 63 cm and reached a maximum age of 7 years. Myrica gale aboveground biomass was 604 g m−2 with stems contributing 75%, leaves 24%, and reproductive organs 2%. Similar patterns of biomass distribution have been reported in other peatland low shrubs. Above-ground net production was 392 g m−2 year−1 and total net production estimated to be 549 g m−2 year−1. Nitrogen contents were higher than in other peatland shrubs and ranged from 0.94% in stems ≥ 3 years old to about 2.4% in leaves, nodules, and male flower buds. Carbon contents ranged from 50% in stems s ≥ 3 years old to 56% in male flower buds. The N content of total annual net production was estimated to be 8.6 g m−2 and the C content 281 g m−2. Nitrogen fixation provided 43% of the estimated annual N requirement.

Seasonal pattern of energy use, respiration, and nitrogenase activity in root nodules of Myrica gale

1983 ◽  
Vol 61 (11) ◽  
pp. 2937-2942 ◽  
Author(s):  
Christa R. Schwintzer ◽  
John D. Tjepkema
Keyword(s):  
Energy Cost ◽  
Energy Use ◽  
Nitrogenase Activity ◽  
Root Nodules ◽  
Seasonal Pattern ◽  
Uptake Ratio ◽  
Experimental Conditions ◽  
Myrica Gale ◽  
Net Production ◽  
N Requirement

Annual CO2 evolution, H2 evolution, and C2H2 reduction were measured in root nodules from a vigorous Myrica gale stand in a Massachusetts peatland at 3-week intervals in 1980. Nodule activity was approximately the same under the experimental conditions (excised nodules reducing C2H2) as in nature (attached nodules reducing N2) and the CO2 evolution to O2 uptake ratio averaged 1.07. Nitrogenase activity was first detectable in late May, reached its maximum [Formula: see text] in mid-July, and disappeared in late October. The seasonal pattern of CO2 evolution was similar except that it continued at low rates when nitrogenase activity was absent. Hydrogen evolution was barely detectable. The energy cost of nitrogen fixation, expressed as the molar CO2:C2H4 ratio, was relatively low [Formula: see text] throughout the period of substantial nitrogenase activity and had a mean annual value of 4.9. Annual N2 fixation was estimated to be 2.8 g N m−2year−1, contributing about 33% of the annual N requirement measured in 1979. Annual C use by nodules was about 21.0 g C m−2 year−1. If this C were available for additional net production, it would increase it by about 5.5%.

scholarly journals Formation of reproductive organs in an early-ripening soybean variety, depending on the daylight duration

2021 ◽  
Vol 36 ◽  
pp. 02005
Author(s):  
Valentina Sinegovskaya ◽  
Anna Levina
Keyword(s):  
Growth And Development ◽  
Growing Season ◽  
Vegetation Period ◽  
Reproductive Organs ◽  
Light Conditions ◽  
Soybean Variety ◽  
Seed Productivity ◽  
Early Ripening ◽  
Soybean Plants ◽  
Sowing Period

To study the reaction of an early-ripening soybean variety to the formation of plant reproductive organs under the influence of different length of daylight hours, studies of 2 sowing periods in a growing house with a new early-ripening variety Sentyabrinka of the FSBSI FRC VNII of Soybean were conducted. Artificial reduction of the daylight duration to 8 hours was established from the phase of the 3rd triple leaf with alternating day and night periods in each variant 7 times during the growing season. The control was plants whose growth and development took place in natural light conditions. According to the research results, it was found that the change in the daylight duration during the vegetation period had a significant impact on the duration of the phases of plant growth and development, the growing season as a whole. When sowing soybeans on May 28 with a natural daylight, the height of plants and their seed productivity were higher than those of plants with a shortened daylight. At this sowing period, the highest productivity was obtained from one plant – 9.3 g, which is 1.0 g more compared to soybean plants with a sowing period of June 3. The growth of plants, the formation of reproductive organs and the seed productivity of the early-repining variety Sentyabrinka depended on the duration of daylight, which can be regulated by the sowing period.

scholarly journals Cajander larch (<i>Larix cajanderi</i>) biomass distribution, fire regime and post-fire recovery in northeastern Siberia

2012 ◽  
Vol 9 (10) ◽  
pp. 3943-3959 ◽  
Author(s):  
L. T. Berner ◽  
P. S. A. Beck ◽  
M. M. Loranty ◽  
H. D. Alexander ◽  
M. C. Mack ◽  
...  
Keyword(s):  
Satellite Imagery ◽  
Aboveground Biomass ◽  
Forest Biomass ◽  
Burned Area ◽  
Forest Disturbances ◽  
Biomass Distribution ◽  
Fire Size ◽  
Northeastern Siberia ◽  
Fire Activity ◽  
Larix Cajanderi

Abstract. Climate change and land-use activities are increasing fire activity across much of the Siberian boreal forest, yet the climate feedbacks from forest disturbances remain difficult to quantify due to limited information on forest biomass distribution, disturbance regimes and post-disturbance ecosystem recovery. Our primary objective here was to analyse post-fire accumulation of Cajander larch (Larix cajanderi Mayr.) aboveground biomass for a 100 000 km2 area of open forest in far northeastern Siberia. In addition to examining effects of fire size and topography on post-fire larch aboveground biomass, we assessed regional fire rotation and density, as well as performance of burned area maps generated from MODIS satellite imagery. Using Landsat imagery, we mapped 116 fire scar perimeters that dated c. 1966–2007. We then mapped larch aboveground biomass by linking field biomass measurements to tree shadows mapped synergistically from WorldView-1 and Landsat 5 satellite imagery. Larch aboveground biomass tended to be low during early succession (≤ 25 yr, 271 ± 26 g m−2, n = 66 [mean ± SE]) and decreased with increasing elevation and northwardly aspect. Larch aboveground biomass tended to be higher during mid-succession (33–38 yr, 746 ± 100 g m−2, n = 32), though was highly variable. The high variability was not associated with topography and potentially reflected differences in post-fire density of tree regrowth. Neither fire size nor latitude were significant predictors of post-fire larch aboveground biomass. Fire activity was considerably higher in the Kolyma Mountains (fire rotation = 110 yr, fire density = 1.0 ± 1.0 fires yr−1 × 104 km−2) than along the forest-tundra border (fire rotation = 792 yr, fire density = 0.3 ± 0.3 fires yr−1 × 104 km−2). The MODIS burned area maps underestimated the total area burned in this region from 2000–2007 by 40%. Tree shadows mapped jointly using high and medium resolution satellite imagery were strongly associated (r2 &amp;approx; 0.9) with field measurements of forest structure, which permitted spatial extrapolation of aboveground biomass to a regional extent. Better understanding of forest biomass distribution, disturbances and post-disturbance recovery is needed to improve predictions of the net climatic feedbacks associated with landscape-scale forest disturbances in northern Eurasia.

scholarly journals Crosstalk Pathway between Trehalose Metabolism and Cytokinin Degradation for the Determination of the Number of Berries per Bunch in Grapes

Cells ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 2378
Author(s):  
Ayane Moriyama ◽  
Chiho Yamaguchi ◽  
Shinichi Enoki ◽  
Yoshinao Aoki ◽  
Shunji Suzuki
Keyword(s):  
Cultured Cells ◽  
Growing Season ◽  
Cytokinin Oxidase ◽  
Flower Formation ◽  
Bud Break ◽  
Flower Buds ◽  
New Information ◽  
Trehalose Metabolism ◽  
Cultivation Techniques

In grapes, the number of flowers per inflorescence determines the compactness of grape bunches. Grape cultivars with tight bunches and thin-skinned berries easily undergo berry splitting, especially in growing areas with heavy rainfall during the grapevine growing season, such as Japan. We report herein that grape cytokinin oxidase/dehydrogenase 5 (VvCKX5) determines the number of berries per inflorescence in grapes. The number of berries per bunch was inversely proportional to the VvCKX5 expression level in juvenile inflorescences among the cultivars tested. VvCKX5 overexpression drastically decreased the number of flower buds per inflorescence in Arabidopsis plants, suggesting that VvCKX5 might be one of the negative regulators of the number of flowers per inflorescence in grapes. Similarly, the overexpression of grape sister of ramose 3 (VvSRA), which encodes trehalose 6-phosphate phosphatase that catalyzes the conversion of trehalose-6-phosphate into trehalose, upregulated AtCKX7 expression in Arabidopsis plants, leading to a decrease in the number of flower buds per Arabidopsis inflorescence. VvCKX5 gene expression was upregulated in grapevine cultured cells and juvenile grape inflorescences treated with trehalose. Finally, injecting trehalose into swelling buds nearing bud break using a microsyringe decreased the number of berries per bunch by half. VvCKX5 overexpression in Arabidopsis plants had no effect on the number of secondary inflorescences from the main inflorescence, and similarly trehalose did not affect pedicel branching on grapevine inflorescences, suggesting that VvCKX5, as well as VvSRA-mediated trehalose metabolism, regulates flower formation but not inflorescence branching. These findings may provide new information on the crosstalk between VvSRA-mediated trehalose metabolism and VvCKX-mediated cytokinin degradation for determining the number of berries per bunch. Furthermore, this study is expected to contribute to the development of innovative cultivation techniques for loosening tight bunches.

scholarly journals Induction of 2n pollen by colchicine in Populus × popularis and its triploids breeding

2011 ◽  
Vol 60 (1-6) ◽  
pp. 155-160 ◽  
Author(s):  
X. J. Xi ◽  
X. B. Jiang ◽  
D. Li ◽  
L. Q. Guo ◽  
J. F. Zhang ◽  
...  
Keyword(s):  
Treatment Process ◽  
Orthogonal Design ◽  
Male Flower ◽  
Colchicine Treatment ◽  
2N Pollen ◽  
Chromosome Counting ◽  
Flower Buds ◽  
Diakinesis Stage ◽  
Populus Popularis ◽  
Different Levels

AbstractInduction of 2n pollen is a required technique for cultivating polyploid via sexual polyploidy. Orthogonal design or Taguchi Design was applied to select the best treatment process of 2n pollen induction inPopulus×popularisfrom different levels of the meiosis stage of male flower buds, colchicine concentration, times of injection, and interval between injections. Flow cytometry and chromosome counting were used to identify the triploids from the offspring ofP.×euramericana. (Dode) Guinier pollinated with induced pollen ofP.×popularis. The results showed that high 2n pollen rate can be achieved by selecting the flower buds during diakinesis stage in meiosis, and then injecting 0.6% colchicine 4 times with 2 hours interval. The 2n pollen rate reached 62.10% by this process, and two triploids were obtained, which indicates that it is possible for cultivating triploids via 2n pollen induction by colchicine treatment in poplar. Results and protocol related to 2n pollen induction, polyploid identification and effect of 2n pollen in this study might be applicable in polyploidy breeding in sectionAigeirosandTacamahacaof poplar.

scholarly journals The response of grassland productivity, soil carbon content and soil respiration rates to different grazing regimes in a desert steppe in northern China

2014 ◽  
Vol 36 (6) ◽  
pp. 573 ◽  
Author(s):  
Xiangyang Hou ◽  
Zhen Wang ◽  
Schellenberg P. Michael ◽  
Lei Ji ◽  
Xiangjun Yun
Keyword(s):  
Soil Respiration ◽  
Soil Carbon ◽  
Net Primary Productivity ◽  
Growing Season ◽  
Northern China ◽  
Rotational Grazing ◽  
Carbon And Nitrogen ◽  
Continuous Grazing ◽  
Significant Difference ◽  
Nitrogen Contents

Soil respiration is a major process for organic carbon losses from arid ecosystems. A field experiment was conducted in 2010 and 2012 on the responses to continuous grazing, rotational grazing and no grazing on desert steppe vegetation in northern China. The growing season in 2010 was relatively dry and in 2012 was relatively wet. The results showed that mean soil respiration was the highest with no grazing in both growing seasons. Compared with no grazing, the soil respiration was decreased by 23.0% under continuous grazing and 14.1% under seasonal rotational grazing. Soil respiration increased linearly with increasing soil water gravimetric content, aboveground net primary productivity (ANPP), belowground net primary productivity (BNPP) and soil carbon and nitrogen contents across the 2 years, whereas a negative correlation was detected between soil respiration and soil temperature. A significant decrease in soil respiration was observed under both continuous grazing and in seasonal rotational grazing in the dry growing season, but no significant difference was detected in the wet growing season. In the wet year, only a non-significant difference in soil respiration was observed between different grazing types. Patterns of seasonal precipitation strongly affected the temporal changes of soil respiration as well as its response to different grazing types. The findings highlight the importance of differences in abiotic (soil temperature, soil water gravimetric content and soil carbon and nitrogen contents) and biotic (ANPP, BNPP and litter mass) factors in mediating the responses of soil respiration to the different grazing regimes.

Above- and be Bow-ground biomass of precompetitive red pine in northern Michigan

1995 ◽  
Vol 25 (7) ◽  
pp. 1064-1069 ◽  
Author(s):  
David D. Reed ◽  
Glenn D. Mroz ◽  
Hal O. Liechty ◽  
Elizabeth A. Jones ◽  
Peter J. Cattelino ◽  
...  
Keyword(s):  
Aboveground Biomass ◽  
Growth Index ◽  
Tree Height ◽  
Growing Season ◽  
Height Growth ◽  
Red Pine ◽  
Basal Diameter ◽  
Total Height ◽  
Ground Biomass ◽  
Northern Michigan

In 1984, red pine (Pinusresinosa Ait.) plantations were established at three sites in northern Michigan. From 1985 through 1992, 3083 individual trees from these stands were destructively sampled to determine aboveground biomass. The root systems were excavated on a subset of these trees (975 individuals). There were no significant differences in the relationships between either above- or below-ground biomass and groundline diameter and tree height across the range of biomass (3–6720 g for aboveground biomass and 1–319 g for belowground biomass), basal diameter (0.3–10.1 cm), or height (10–417 cm) of the sampled trees. There were also no significant differences in these relationships among the three sites. Relative height growth (the ratio of total height increment in a year and the total height at the beginning of the growing season) was found to have a very well defined maximum that was a function of total height at the beginning of the growing season. This maximum relative growth rate was used to develop a new height growth index that can be used to identify precompetitive red pine that are approaching their potential height growth in field situations.

scholarly journals The growth of flower bud, life history, and population structure of Rafflesia arnoldii (Rafflesiaceae) in Bengkulu, Sumatra, Indonesia

2020 ◽  
Vol 21 (2) ◽  
Author(s):  
AGUS SUSATYA
Keyword(s):  
Population Structure ◽  
Life History ◽  
Male Flower ◽  
Female Flower ◽  
Exponential Model ◽  
Flower Buds ◽  
Flower Bud ◽  
Dynamics Of Population ◽  
History Of ◽  
Two Populations

Abstract. Susatya A. 2020. The growth of flower bud, life history, and population structure of Rafflesia arnoldii (Rafflesiaceae) in Bengkulu, Sumatra, Indonesia. Biodiversitas 21: 792-798. The life history of Rafflesia arnoldii R.Br. is the reflection of the complex interaction between flower bud development and the external environments in order to reach its optimal survivorship. The objectives of the study were to determine the growth of flower buds at various development stages, to reconstruct the life history, and to know the population structure of R. arnoldii. The study was carried out at Taba Penanjung, Bengkulu Province, Indonesia. Two populations consisting of 17 individual buds of R. arnoldii were selected for the research. All buds were categorized into six visible stages, mapped, measured their diameters, and recorded their fates every two weeks for six months. The exponential model of growth development was applied to reconstruct the life history. The results showed that buds from the perigone stage respectively grew 3.5 and 12 times faster than those from the bract and cupule stages. The exponential growth of flower bud was confirmed, and explained by Y = 0.785 e0.0052 X, where Y and X were respectively diameter and age of flower bud. The complete life history of R. arnoldii required 3.5 to 5 years, where a female flower needed a longer time than a male flower. The population structure of R. arnoldii was not constant, but changed dynamically over time. The dynamics of population structure was mainly caused by the high mortality of small buds and the low flower bud recruitment.

scholarly journals ALLOMETRIC MODELS FOR ESTIMATING ABOVEGROUND BIOMASS AND BIOMASS ALLOCATION OF CAPIXINGUI TREES (Croton floribundus Spreng.) IN AN AGRISILVICULTURAL SYSTEM

2016 ◽  
Vol 40 (2) ◽  
pp. 279-288 ◽  
Author(s):  
Maria Luiza Franceschi Nicodemo ◽  
Marcelo Dias Muller ◽  
Antônio Aparecido Carpanezzi ◽  
Vanderley Porfírio-da-Silva
Keyword(s):  
Aboveground Biomass ◽  
Stem Diameter ◽  
Distribution Model ◽  
Biomass Estimation ◽  
Total Biomass ◽  
Biomass Distribution ◽  
Residual Distribution ◽  
Allometric Models ◽  
Crown Diameter ◽  
Bole Biomass

ABSTRACT The objective of this study was to select allometric models to estimate total and pooled aboveground biomass of 4.5-year-old capixingui trees established in an agrisilvicultural system. Aboveground biomass distribution of capixingui was also evaluated. Single- (diameter at breast height [DBH] or crown diameter or stem diameter as the independent variable) and double-entry (DBH or crown diameter or stem diameter and total height as independent variables) models were studied. The estimated total biomass was 17.3 t.ha-1, corresponding to 86.6 kg per tree. All models showed a good fit to the data (R2ad > 0.85) for bole, branches, and total biomass. DBH-based models presented the best residual distribution. Model lnW = b0 + b1* lnDBH can be recommended for aboveground biomass estimation. Lower coefficients were obtained for leaves (R2ad > 82%). Biomass distribution followed the order: bole>branches>leaves. Bole biomass percentage decreased with increasing DBH of the trees, whereas branch biomass increased.

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