Abstract This paper examines the role that compensation plays in determining plant response to stress. In addition exploring compensatory responses individual stresses, multiple stresses induce different strategies are considered. To do this we have utilized results of many experiments conducted by Response Plants Interacting Stresses (ROPIS) project. Similarities and differences plants considered as a function growth habits viz. herbaceous annuals, deciduous evergreen perennials. The...

The proliferation of roots in soil microenvironments was studied to gain an understanding how nitrogen (N) stress affects root growth. By placing one major lateral (<10% the system) a Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) seedling into small pot (microenvironment) and remaining large pot, it possible manipulate growth part system while having only minor effects on entire seedling. Nitrogen successfully induced by large-pot treatments resulted greatly decreased foliage slightly...

We established Populus deltoides Bartr. stands differing in nitrogen (N) availability and tested if: (1) N-induced carbon (C) allocation could be explained by developmental controls; (2) N uptake per unit root mass, i.e., specific N-uptake rate, increased with availability. Closely spaced (1 × 1 m) were treated 50, 100 200 kg ha −1 year of time-release balanced fertilizer (50N, 100N 200N) compared unfertilized controls (0N). Measurements made during two complete growing seasons from May 1998...

Abstract This paper addresses common patterns of plant C allocation in response to stress. The ROPIS studies used species ranging from slow growing, long‐lived evergreen trees (red spruce [ Picea rubens Sarg.] and ponderosa pine Pinus Dougl.]), fast growing deciduous (loblolly taeda L.] aspen Populus tremulaides Michx.]) annuals (radish Raphanus sativus L.]). Several factors helped explain the effects ozone, stress all experiments, on these diverse species. Species with high relative growth...

Root morphology, biomass, and (14)C distribution were studied in two 2-year-old Populus trichocarpa x P. deltoides hybrids, which originated from hardwood cuttings, to determine the pattern of root a plantation refine methods for recovery. The trees labeled with (14)CO(2) harvested after 72-hour chase period. Roots attached each tree analyzed morphological traits at time harvest. Detached roots within 1-m(3) volume soil surrounding separated sorted on basis rooting depth diameter. Lateral >...

A closely spaced (1 x 1 m) cottonwood (Populus deltoides Bartr.) plantation was established to evaluate the effects of nutrient availability on fine root dynamics. Slow-release fertilizer (17:6:12 N,P,K plus micronutrients) applied 225-m(2) plots at 0, 50, 100 and 200 kg N ha(-1), were monitored for two growing seasons. Fine production, mortality, live standing crop life span analyzed based monthly minirhizotron observations. biomass measured in soil cores. dynamics controlled more by...

Carbon (C) allocation to the perennial coarse-root system of trees contributes ecosystem C sequestration through formation long-lived live wood biomass and, following senescence, by providing a large source nutrient-poor detrital C. Our understanding controls on growth is rudimentary, but it has important implications for projecting belowground net primary production responses global change. Age-related changes in coarse roots represent critical uncertainty modeling landscape-scale storage...

Abstract We analyzed growth data from model aspen ( Populus tremuloides Michx.) forest ecosystems grown in elevated atmospheric carbon dioxide ([CO 2 ]; 518 μL L −1 ) and ozone concentrations ([O 3 1.5 × background of 30–40 nL during daylight hours) for 7 years using free‐air CO enrichment technology to determine how interannual variability present‐day climate might affect responses either gas. also tested whether effects those gasses were sustained over time. Elevated [CO ] increased tree...

To explore the physiological mechanisms underlying ozone-induced growth reductions in loblolly pine (Pinus taeda L.), seedlings were exposed to sub-ambient (charcoal-filtered), ambient or twice-ambient ozone open-top chambers for three growing seasons. In final year of exposure, current-year needle fascicles labeled with (14)CO(2) and incorporation (14)C into biochemical fractions was followed 48 hours. Irrespective treatment, losses (14)C-assimilates from foliage respiration translocation...

Forestland application of poultry manure offers an alternative to the conventional practice pastureland application. Before such a is considered viable, however, it must be demonstrated that forest ecosystem capable absorbing nutrients contained in manure, especially nitrogen (N) and phosphorus (P). From forestry perspective, also tree growth not diminished. We investigated these questions using loblolly pine (Pinus taeda L.) stands growing central Mississippi area high production....

Maximization of short-rotation forest plantation yield requires frequent applications nutrients, especially nitrogen (N). Whole-plant growth is known to be sensitive the proportion ammonium nitrate (NH4:NO3). However, extent which N form affects root growth, branching and morphology poorly understood, these variables may have substantial impacts on plant nutrient water acquisition. We used rooted cuttings cottonwood (Populus deltoides Bartr. ex Marsh.) investigate effect various NH4:NO3...

Seasonal patterns of biomass accumulation and carbon allocation were determined for 1-year-old loblolly pine (Pinustaeda L.) seedlings grown in soil having either 15 or 35 μg Mg•g −1 exposed to subambient, ambient, twice ambient levels ozone (O 3 ) simulated rainfall at pH 3.8 5.2 open-top chambers. Seedlings harvested during the 1988 dormancy period, immediately prior bud break 1989, first third foliar growth flushes end 1989 growing season. At each harvest, individual seedling components...

Under experimental conditions, the growth of loblolly pine (Pinus taeda L.) is often responsive to ozone at near-ambient concentrations. However, little known biochemical changes associated with this or other pollutants. Loblolly seedlings in open-top chambers were exposed combinations (sub-ambient, ambient, twice-ambient), acidic precipitation (pH 3.8 pH 5.2) and soil magnesium (0.15 0.32 microg g(-1) exchangeable Mg) for three growing seasons. The effects these treatments greater foliage...

Aluminum (Al) distribution among several cellular fractions was investigated in root tips of seedlings one Al-resistant and Al-sensitive family slash pine (Pinus elliottii Engelm.) loblolly taeda L.) grown nutrient solution containing 100 μM AlCl3 (pH 4) for 167 h. present 5-mm-long fractionated into cell-wall-labile (desorbed 0.5 mM citric acid), cell-wall-bound (retained after filtering disrupted cells through 20-μm mesh) symplasmic (filtrate following cell disruption) fractions. When...

In response to concerns about aluminum and HCl exposure associated with rocket motor testing launches, survival growth of full-sib families loblolly pine (Pinus taeda L.) slash elliottii Engelm.) were evaluated in a nursery bed experiment. Each species was exposed single soil application chloride (0.33 M AlCl3, pH 2.5), hydrochloric acid (0.39 HCl, 0.6) or water, without mycorrhizal inoculation Pisolithus tinctorius (Coker Couch). After 20 weeks inoculation, AlCl3 treatments averaged 52% for...

A complex of nine invasive weevils has established in the northern hardwood forests Great Lakes Region. These have become numerically dominant arthropod fauna lower vegetation strata this ecosystem. Effects these folivorous adults and rhizophagous larvae on seedling survival density are unknown. We measured impact adult weevil defoliation individual sugar maple (Acer saccharum Marshall) seedlings, flora stands. Over 14 500 seedlings were to examine effects larval abundance, dynamics during...

(1999). Genetic Linkage Mapping of Genomic Regions Conferring Tolerance to High Aluminum in Slash Pine. Journal Sustainable Forestry: Vol. 10, No. 1-2, pp. 69-78.