Growth, nutrient dynamics, and ectomycorrhizal development of container-grownPicea marianaseedlings in response to exponential nutrient loading

2000 ◽  
Vol 30 (2) ◽  
pp. 191-201 ◽  
Author(s):  
M Quoreshi ◽  
V R Timmer
Keyword(s):  
Steady State ◽  
Nutrient Dynamics ◽  
Nutrient Loading ◽  
Black Spruce ◽  
Growth Dynamics ◽  
High Loading ◽  
Fungal Colonization ◽  
Exponential Fertilization ◽  
N Rates ◽  
Nutrient Reserves

Containerized black spruce (Picea mariana (Mill.) BSP) seedlings fertilized conventionally (12.5 mg N/plant) or exponentially (12.5, 25, or 50 mg N/plant) and inoculated with Hebeloma crustuliniforme (Bull. Ex St-Amans) Quel. or Laccaria bicolor (R. Mre.) Orton were periodically monitored for a 20-week greenhouse rotation to assess growth dynamics, steady-state N and P nutrition, and ectomycorrhizal development. Growth and nutrient accumulation increased exponentially for the exponential regimes and more linearly for the conventional regime, although final biomass was similar except for the low-dose exponential addition. Shoot/root biomass ratios were relatively stable for most of the growing season, characterizing steady-state nutrient supply that benefits seedling outplanting performance and mycorrhizal colonization. Exponential fertilization also stimulated mycorrhiza formation even at high loading (25 or 50 mg N) rates that build up nutrient reserves in the seedlings without affecting seedling size. Plant nutrient uptake was more efficient under exponential fertilization and (or) fungal colonization, although efficiency dropped off at high loading levels. Vector nutrient diagnosis revealed marked nutrient dilution under conventional fertilization, but steady-state nutrition under exponential fertilization that coincided with satisfactory mycorrhiza development on seedlings. Dilution-free nutrient conditions for seedlings may provide stable carbohydrates for symbiosis and may develop enhanced tolerance to high fertilizer inputs.

Biomass partitioning and nitrogen retranslocation in black spruce seedlings on competitive mixedwood sites: a bioassay study

1998 ◽  
Vol 28 (2) ◽  
pp. 206-215 ◽  
Author(s):  
V Malik ◽  
V R Timmer
Keyword(s):  
Nutrient Dynamics ◽  
Nutrient Loading ◽  
Black Spruce ◽  
N Uptake ◽  
Natural Vegetation ◽  
Nursery Culture ◽  
Nitrogen Retranslocation ◽  
Nutrient Retranslocation ◽  
Herbicide Effects ◽  
Nutrient Reserves

Black spruce (Picea mariana (Mill.) BSP) seedlings were exponentially nutrient loaded by applying 3 or 6 times more fertilizer than recommended for conventional seedling production in the nursery. Loaded seedlings were similar in height and biomass to nonloaded seedlings after nursery culture, but their tissue N, P, and K content was almost twice as much as that of nonloaded seedlings. The seedlings were transplanted on intact potted substrates (bioassays) retrieved with natural vegetation from two boreal mixedwood sites and grown for one season in a greenhouse to study early- and late-season growth and nutrient dynamics, and nutrient loading and herbicide effects on N retranslocation processes. After transplanting, height and biomass growth of loaded seedlings were, respectively, 9-14% and 24-49% more than nonloaded seedlings in herbicide-treated plots, and 14-32% and 42-85% more in untreated plots, resulting in 32-39% biomass reduction in natural vegetation. The effect of nutrient loading on growth was attributed to earlier and greater biomass and N partitioning to current needles and roots that promoted N uptake (up to 20.9 ± 1.7 mg) compared with nonloaded seedlings (up to 11.8 ± 1.2 mg). Although both loading and herbicide treatments stimulated seedling growth and N uptake, N retranslocation from older to actively growing tissues was promoted by loading but reduced by herbicide treatment. The results demonstrate the high dependence of seedlings on internal nutrient reserves when planted in competitive environments, and that nutrient retranslocation is mainly driven by current growth, nutrient uptake, and internal nutrient reserves.

Exponential fertilization increases nutrient uptake and ectomycorrhizal development of black spruce seedlings

1998 ◽  
Vol 28 (5) ◽  
pp. 674-682 ◽  
Author(s):  
A M Quoreshi ◽  
V R Timmer
Keyword(s):  
Nutrient Loading ◽  
Black Spruce ◽  
Matter Production ◽  
Seedling Biomass ◽  
Nursery Stock ◽  
Constant Rate ◽  
Greenhouse Culture ◽  
Addition Rate ◽  
Exponential Fertilization ◽  
Mycorrhizal Development

Intensive fertilization may inhibit adequate mycorrhizal development for forest nursery stock production. Containerized black spruce (Picea mariana (Mill.) BSP) seedlings exposed to four fertilization regimes (one conventional and three exponential at 12.5, 12.5, 25, and 50 mg N/seedling, respectively) and two ectomycorrhizal inoculations (Hebeloma crustuliniforme (Bull. ex St-Amans) Quel. and Laccaria bicolor (R. Mre.) Orton) were grown from seed to assess mycorrhizal formation and nutrition of young trees under intensive greenhouse culture. Exponentially increasing fertilizer additions stimulated ectomycorrhizal development (49-85%) compared with conventional constant-rate fertilization (22-26%). Exponential fertilization also increased seedling N (13-34%) and P (5-18%) uptake, although dry matter production was reduced (17-25%) at the lowest exponential addition rate. Ectomycorrhizal inoculation did not affect seedling biomass but increased uptake of N (6-17%), P (5-20%), and K (4-18%), demonstrating a potential for nutrient loading by fungi. Higher ectomycorrhizal formation found under exponential fertilization regimes was attributed to lower initial nutrient levels maintained in the growing media. Results indicate that high exponential fertilization combined with fungal inoculation may be effective for producing both nutrient-loaded and ectomycorrhizally infected planting stock.

Growth, nutrient dynamics, and interspecific competition of nutrient-loaded black spruce seedlings on a boreal mixedwood site

1996 ◽  
Vol 26 (9) ◽  
pp. 1651-1659 ◽  
Author(s):  
V. Malik ◽  
V.R. Timmer
Keyword(s):  
Interspecific Competition ◽  
Nutrient Dynamics ◽  
Nutrient Loading ◽  
Black Spruce ◽  
Nutrient Utilization ◽  
First Year ◽  
N Availability ◽  
Growing Seasons ◽  
Naturally Occurring ◽  
Nutrient Resources

Nutrient-loaded and conventionally fertilized containerized black spruce (Piceamariana (Mill.) BSP) seedlings were planted on a boreal mixedwood site in the Greater Clay Belt of Ontario to study their growth and interaction with natural vegetation. At planting, nutrient-loaded seedlings were similar in height and biomass to conventionally fertilized seedlings, but contained 39, 69, and 22% more tissue N, P, and K content, respectively. After two field growing seasons, nutrient-loaded seedlings attained 15–18% more height and 16–39% more biomass, resulting in 15–27% reduction in the biomass of neighbouring vegetation. Aboveground biomasses of seedlings and neighbouring vegetation were inversely related. Interspecific competition was more intense in the second year than in the first year of outplanting. Nutrient loading prior to planting stimulated nutrient uptake and root growth after planting, and reduced soil N availability by 6–20% during the first season, suggesting greater preemption of belowground nutrient resources. The enhanced competitive ability of loaded seedlings over naturally occurring vegetation was probably due to the contrasting nutrient utilization traits induced by greenhouse fertilization. Nutrient-loaded seedlings translocated more nutrients to actively growing parts from reserves built up during the greenhouse preconditioning phase than did conventionally fertilized seedlings. First-season growth and nutrient responses in the field and in previous greenhouse trials were significantly correlated, demonstrating the effectiveness of using intact bioassays to simulate and predict short-term field responses to competition treatments.

Steady-state nutrient preconditioning and early outplanting performance of containerized black spruce seedlings

1991 ◽  
Vol 21 (5) ◽  
pp. 585-594 ◽  
Author(s):  
V. R. Timmer ◽  
G. Armstrong ◽  
B. D. Miller
Keyword(s):  
Steady State ◽  
Nutrient Uptake ◽  
Dose Level ◽  
Nutrient Loading ◽  
Black Spruce ◽  
Nutrient Status ◽  
Shoot Biomass ◽  
Exponential Growth Phase ◽  
Nutrient Culture ◽  
Outplanting Performance

Conventional fertilization of black spruce (Piceamariana (Mill.) B.S.P.) container stock usually does not conform to steady-state nutrient conditions and may limit subsequent outplanting performance. Steady-state nutrient preconditioning of seedlings, characterized by maintaining stable tissue nutrient (N, P, and K) concentrations during the exponential growth phase, was induced by an exponentially based fertilization regime that compensated for low nutrient reserves in germinating seeds. By the end of the greenhouse rotation, this regime reduced the shoot/root ratio of the trees, but fell short of increasing seedling growth and nutrient status when compared with seedlings conventionally fertilized with equivalent amounts of nutrients. However, first-season height growth and shoot biomass of trees outplanted on different surface soils in pot bioassays were significantly improved by steady-state nutrient preconditioning and were accompanied by increased plant nutrient uptake, particularly N at the half-dose level and P at the full-dose level. Out-planting performance was higher on an upland site type, although relative response was greater on nutrient-poorer, lowland substrates. The preconditioning response from exponentially based fertilization was attributed to lower shoot/root mass ratio and more effective nutritional adaptation of the seedlings to the field environment. Under steady-state nutrient culture, seedling nutrient uptake conforms more closely with stable nutrient supply in nature, since expanding root systems exploit new soil volumes exponentially. Field performance of exponentially fertilized seedlings may be further enhanced when combined with balanced nutrient loading in the greenhouse phase.

scholarly journals Aquatic macrophytes can be used for wastewater polishing but not for purification in constructed wetlands

2017 ◽  
Vol 14 (4) ◽  
pp. 755-766 ◽  
Author(s):  
Yingying Tang ◽  
Sarah F. Harpenslager ◽  
Monique M. L. van Kempen ◽  
Evi J. H. Verbaarschot ◽  
Laury M. J. M. Loeffen ◽  
...  
Keyword(s):  
Plant Species ◽  
Constructed Wetlands ◽  
Aquatic Macrophytes ◽  
Nutrient Dynamics ◽  
Nutrient Loading ◽  
Controlled Study ◽  
Ceratophyllum Demersum ◽  
Nutrient Distribution ◽  
Azolla Filiculoides ◽  
Sediment Types

Abstract. The sequestration of nutrients from surface waters by aquatic macrophytes and sediments provides an important service to both natural and constructed wetlands. While emergent species take up nutrients from the sediment, submerged and floating macrophytes filter nutrients directly from the surface water, which may be more efficient in constructed wetlands. It remains unclear, however, whether their efficiency is sufficient for wastewater purification and how plant species and nutrient loading affects nutrient distribution over plants, water and sediment. We therefore determined nutrient removal efficiencies of different vegetation (Azolla filiculoides, Ceratophyllum demersum and Myriophyllum spicatum) and sediment types (clay, peaty clay and peat) at three nutrient input rates, in a full factorial, outdoor mesocosm experiment. At low loading (0.43 mg P m−2 d−1), plant uptake was the main pathway (100 %) for phosphorus (P) removal, while sediments showed a net P release. A. filiculoides and M. spicatum showed the highest biomass production and could be harvested regularly for nutrient recycling, whereas C. demersum was outcompeted by spontaneously developing macrophytes and algae. Higher nutrient loading only stimulated A. filiculoides growth. At higher rates ( ≥  21.4 mg P m−2 d−1), 50–90 % of added P ended up in sediments, with peat sediments becoming more easily saturated. For nitrogen (N), 45–90 % was either taken up by the sediment or lost to the atmosphere at loadings  ≥  62 mg N m−2 d−1. This shows that aquatic macrophytes can indeed function as an efficient nutrient filter but only for low loading rates (polishing) and not for high rates (purification). The outcome of this controlled study not only contributes to our understanding of nutrient dynamics in constructed wetlands but also shows the differential effects of wetland sediment types and plant species. Furthermore, the acquired knowledge may benefit the application of macrophyte harvesting to remove and recycle nutrients from both constructed wetlands and nutrient-loaded natural wetlands.

Vector competition analysis of black spruce seedling responses to nutrient loading and vegetation control

1999 ◽  
Vol 29 (4) ◽  
pp. 474-486 ◽  
Author(s):  
Moses Imo ◽  
Victor R Timmer
Keyword(s):  
Nutrient Loading ◽  
Black Spruce ◽  
Forest Site ◽  
Herbicide Application ◽  
Competition Analysis ◽  
Vegetation Control ◽  
Weed Growth ◽  
Forest Sites ◽  
Seedling Biomass ◽  
Site Field

Impacts of methods to overcome competing vegetation (fertilization, herbicide application, and shading) on conventional and nutrient-loaded black spruce (Picea mariana (Mill.) BSP) seedlings were examined on six forest site types in northeastern Ontario using vector competition analysis. Four sites (Alnus; hardwood; mixedwood, herb rich; and mixedwood, herb poor) were selected to represent high competition, and two sites (feathermoss and Vaccinium) to represent low-competition forest sites. Although similar in biomass before planting, loaded seedlings had greater N, P, and K content than nonloaded seedlings. After planting, loaded seedlings outperformed growth of nonloaded seedlings under all vegetation-control treatments on all sites. Herbicide application eliminated noncrop vegetation but resulted in significantly higher seedling biomass only on the high-competition Alnus site. Field fertilization stimulated weed growth resulting in seedling suppression on the high-competition sites, while nutrient loading countered weed competition on most sites. Interpretation of these results by vector competition analysis revealed that, without fertilization, competition for nutrients was the primary factor limiting seedling growth, while competition for light and (or) moisture was greater after fertilizer addition on weed-prone sites. Similar interpretation revealed no seedling-weed interactions in the less competitive sites.

Interaction of nutrient-loaded black spruce seedlings with neighbouring vegetation in greenhouse environments

1995 ◽  
Vol 25 (6) ◽  
pp. 1017-1023 ◽  
Author(s):  
Vikram Malik ◽  
Victor R. Timmer
Keyword(s):  
Negative Correlation ◽  
Competitive Ability ◽  
Black Spruce ◽  
Biomass Accumulation ◽  
Growing Season ◽  
Significant Negative Correlation ◽  
Biomass Growth ◽  
Naturally Occurring ◽  
Nutrient Reserves ◽  
Accumulation Slope

The interaction of newly planted, nutrient-loaded black spruce (Piceamariana (Mill.) B.S.P.) seedlings with naturally occurring vegetation was investigated for one growing season under greenhouse conditions using bioassays retrieved from a boreal mixedwood site. Nutrient-loaded seedlings were similar in height and biomass to conventionally fertilized seedlings at planting, but contained 43, 76, and 33% more tissue N, P, and K content due to higher nursery fertilization, which induced luxury consumption. Nutrient-loaded seedlings outperformed conventionally fertilized seedlings in respective height and biomass growth by 35 and 28% in herbicide-treated plots, and by 44 and 37% in untreated plots, resulting in a 27% reduction in neighbouring vegetation biomass by the end of the season. The loading treatments stimulated nutrient uptake after planting, although the depletion of preplant nutrient reserves was greater. A significant negative correlation was observed between tree and weed biomass accumulation. Slope differences indicated that loaded trees were less sensitive to neighbouring vegetation than conventionally fertilized trees. The enhanced competitive ability of loaded seedlings against naturally occurring vegetation was probably due to the translocation of more nutrients to actively growing parts from reserves built up during the nursery preconditioning phase.

Growth and nitrogen retranslocation of nutrient loaded Picea mariana seedlings planted on boreal mixedwood sites

2001 ◽  
Vol 31 (8) ◽  
pp. 1357-1366 ◽  
Author(s):  
Moses Imo ◽  
Victor R Timmer
Keyword(s):  
Picea Mariana ◽  
Nutrient Loading ◽  
Black Spruce ◽  
N Uptake ◽  
Nutrient Mobilization ◽  
N Accumulation ◽  
Northern Ontario ◽  
Nursery Culture ◽  
Forest Sites ◽  
Seedling Biomass

Enhanced nutrient mobilization from old to current growth is a key mechanism that confers competitive ability to nutrient-loaded black spruce (Picea mariana (Mill.) BSP) seedlings planted on high-competition forest sites in northern Ontario. This study examines effects of nutrient loading and differing vegetation management (herbicide, fertilization, shading) on growth, partitioning, and net retranslocation of N between current and old shoots of newly planted black spruce seedlings on six contrasting boreal sites. Nutrient loading during nursery culture improved seedling growth and N uptake and retranslocation after transplanting. Herbicide application accelerated growth and N uptake only on the high-competition Alnus, hardwood, and mixedwood sites but had no effect on the less competitive feathermoss and Vaccinium sites. Weed removal on competitive sites reduced N retranslocation significantly. Field fertilization reduced N retranslocation in seedlings and promoting tree growth and N uptake on the less competitive feathermoss and Vaccinium sites. However, fertilization stimulated weeds on high-competition sites suppressing seedling biomass and N uptake. Factors that seem to affect net N retranslocation include the type and level of internal N reserves, biomass and N accumulation and partitioning, external N supply, and other stresses that limit plant growth such as competition.

Sign in / Sign up

Export Citation Format

Share Document