scholarly journals Planting Density and Site Effects on Stem Dimensions, Stand Productivity, Biomass Partitioning, Carbon Stocks and Soil Nutrient Supply in Hybrid Poplar Plantations

Forests ◽  
2018 ◽  
Vol 9 (6) ◽  
pp. 293 ◽  
Author(s):  
Benoit Truax ◽  
Julien Fortier ◽  
Daniel Gagnon ◽  
France Lambert
Keyword(s):  
Site Effects ◽  
Hybrid Poplar ◽  
Soil Nutrient ◽  
Nutrient Supply ◽  
Carbon Stocks ◽  
Biomass Partitioning ◽  
Planting Density ◽  
Stand Productivity ◽  
Poplar Plantations

Have repeated applications of nitrogen and phosphorus to a loblolly pine plantation changed stand productivity and soil nutrient supply?

2008 ◽  
Vol 38 (3) ◽  
pp. 637-644 ◽  
Author(s):  
Jennifer (Bennett) Phelan ◽  
H. Lee Allen
Keyword(s):  
Loblolly Pine ◽  
Soil Nutrient ◽  
Nutrient Supply ◽  
Biologically Active ◽  
Nutrient Concentrations ◽  
Total System ◽  
P Fertilization ◽  
Stand Growth ◽  
Stand Productivity

To develop a nitrogen (N) and phosphorus (P) fertilization regime that produces long-term increases in stand productivity and soil nutrient supply in loblolly pine plantations, a series of N + P fertilizer studies were established in the Southeastern United States. One of these installations was examined partway through the study to determine if changes to stand productivity and soil nutrient supply had already been achieved. Stand growth and foliar nutrient concentrations were measured for 6 years, and during the third year, a seedling bioassay was conducted with soil collected from the highest fertilization and nonfertilized treatments. Annual stand growth was increased by 14%–27% in the fertilized plots suggesting that the fertilizer regime improved stand productivity. However, results from the seedling bioassay showed that only P fertilization had caused changes in soil nutrient supply. Seedling P contents in the fertilized treatments were 3.6 times larger than those in the nonfertilized treatments. In contrast, total system N contents were equivalent in the fertilized and nonfertilized systems, and extractable nitrate (NO3–), ammonium (NH4+), and biologically active N were higher in the nonfertilized soils. Future measurements and seedlings bioassay assessments should be conducted to determine when and if long-term changes in soil quality and stand productivity are achieved.

On the importance of including soil nutrient feedback effects for predicting ecosystem carbon exchange

2003 ◽  
Vol 30 (2) ◽  
pp. 223 ◽  
Author(s):  
Miko U. F. Kirschbaum ◽  
Guillaume Simioni ◽  
Belinda E. Medlyn ◽  
Ross E. McMurtrie
Keyword(s):  
Soil Nutrient ◽  
Nutrient Supply ◽  
Carbon Stocks ◽  
Carbon Gain ◽  
Feedback Effects ◽  
Ecosystem Carbon ◽  
Foliar Nutrient ◽  
And Storage ◽  
Ecosystem Carbon Exchange

To grow, plants need both carbon, which is fixed in photosynthesis, and inorganic nutrients, which are generally obtained from the soil. Much interest currently exists in trying to understand the uptake and storage of carbon by terrestrial ecosystems. This paper investigates to what extent carbon gain and storage are modified by soil nutrient availability. This issue is investigated in relation to both short-term carbon fluxes on the time scale of interannual variability and long-term ecosystem carbon stocks on time scales of several thousand years.We conclude from simulations with an ecosystem model (CenW) that interannual variations in carbon gain can be significantly affected by feedback effects through the nutrient cycle. This feedback effect operates principally through an imbalance between carbon and nutrient dynamics. In years that allow high carbon gain, nutrient supply typically does not match the increased carbon supply so that foliar nutrient concentrations are reduced. This lowers productivity below that which could be expected if foliar nutrient concentration remained the same. The importance of these feedback effects is shown to be greatest at intermediate levels of water availability and nutrient supply, and is relatively more important for net ecosystem carbon exchange than for net primary production.We conclude that the long-term build-up of carbon stocks in ecosystems is often controlled by the rate at which nutrients can be gained. This conclusion is based on data from published studies showing that the slow build-up of carbon matches the gain in nitrogen, phosphorus and sulfur, and on our simulations of system carbon stocks in response to fertiliser addition.The paper concludes with a discussion of the importance and feasibility of including these processes into models at different scales, including the broad continental scale. For modelling net ecosystem exchange for Australia, it is regarded as feasible and desirable to use models that are constrained by these system-internal feedback effects. Such models have already been used for large-scale simulations in Australia and other countries.

Public perceptions of hybrid poplar plantations: trees as an alternative crop

2007 ◽  
Vol 9 (5) ◽  
pp. 468 ◽  
Author(s):  
Pamela D. Neumann ◽  
Naomi T. Krogman ◽  
Barb R. Thomas
Keyword(s):  
Hybrid Poplar ◽  
Public Perceptions ◽  
Alternative Crop ◽  
Poplar Plantations

scholarly journals SOIL NUTRIENT SUPPLY AND CHIONOCHLOA GRASSES

2012 ◽  
Vol 93 (3) ◽  
pp. 229-232
Author(s):  
Andrew J. Tanentzap ◽  
William G. Lee ◽  
David A. Coomes
Keyword(s):  
Soil Nutrient ◽  
Nutrient Supply

Do soil properties with elevation affect alpine "grass-line"? Findings from Haibei, northern Tibetan Plateau

2021 ◽  
Author(s):  
Zuonan Cao ◽  
Zhenhuan Guan ◽  
Peter Kühn ◽  
Jinsheng He ◽  
Thomas Scholten
Keyword(s):  
Global Warming ◽  
Tibetan Plateau ◽  
Soil Properties ◽  
Growth Parameters ◽  
Soil Nutrient ◽  
Nutrient Supply ◽  
High Mountain ◽  
Northern Tibetan Plateau ◽  
Upper Limit ◽  
Grass Growth

<p>Many species showed that their richness and distribution shifts climate-driven towards higher elevation in Tibetan Plateau. However, vegetation and soil data from alpine grassland elevational gradients are rare (Huang et al., 2018). It is mostly unknown how the "grass-line" will respond to global warming and whether soils play a significant role in the vegetation pattern in high-altitude regions. At a local scale, the growth and distribution of vegetation at its upper limit may depend on nutrient limitation, as shown for treelines from the Himalayas. For example, the limited nutrient supply of soil N, K, Mg, and P becomes more intense with elevation, which declines in nutrient supply spatially coincides with abrupt changes in vegetation composition and growth parameters (Schwab et al., 2016). And low soil nutrient availability could affect tree growth in the Rolwaling Himal, Nepal treeline ecotone (Drollinger et al., 2017). To better understand the interrelationship between soil properties and grass growth at this upper limit, we took random soil samples in 3 altitudes, 3 geomorphic positions with 3 depth increments from Haibei grassland, northern Tibetan Plateau. Soil properties, like texture, bulk density, total C, N, and P fractions, were analyzed and compared to vegetation data.<br>Further, soil and vegetation data from open-top chambers (OTC) experiments to simulate global warming were analyzed better to understand the role of temperature for grass line-shift. The first results show that species composition change with altitude towards grassland plant communities with lower demands for P, which can be compared with the nutrient addition experiment that P addition alone significantly affects species diversity and biomass in the same area (Ren et al., 2016). We suppose that specific combinations of soil properties could limit grass growth and be even more marked than the warming, which controls biodiversity and biomass production in high mountain grassland ecosystems. </p>

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