Tree height and leaf drought tolerance traits shape growth responses across droughts in a temperate broadleaf forest

AbstractRoosting behaviour in diurnal ground-dwelling birds is important to their conservation as they are particularly vulnerable to predation when on their roosts. In 2005, we studied the roosting behaviour of the globally ‘Endangered’ Sichuan Hill-partridge (Arborophila rufipectus) in Laojunshan Nature Reserve, southwest China, a site dominated by evergreen broadleaf forest. Our study showed that the birds roosted on elevated perches and roosting behaviour was associated with social organization. Breeding males roosted alone within their territories before mating or during the female's involvement in incubation, but at other times they roosted with the female bird. After hatching of the brood, the adult males roosted on the ground close to the brooding female for about two weeks. After this time the male left the female and chicks to roost elsewhere in the territory. High vegetation cover around the perch site was a key predictor of roosting sites for the partridges. Only six out of 84 tree and shrub species were typically used by the roosting birds, although individual roosting plants varied from night to night. The median height of roosting plants was 6.9 (3.8–10.5) m, which was significantly lower than many shrubs within the breeding territory. Perches were 1.7–6.4 (median = 2.7) m from the ground and independent of roost tree height, suggesting an optimum roosting height. The partridges preferred roosting sites with denser shrub vegetation. In terms of the species' conservation, our results highlight the importance of protecting primary forest that contains suitable roosting trees and shrubs.

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Impacts of Wire Basket Retention and Removal on Fraxinus americana ‘Autumn Purple’ Growth Nine Years After Transplanting

Arboriculture & Urban Forestry ◽

10.48044/jauf.2019.007 ◽

2019 ◽

Vol 45 (3) ◽

Author(s):

Ryan Klein ◽

Richard Hauer ◽

Andrew Koeser ◽

Bob Bleicher

Keyword(s):

Tree Height ◽

System Stability ◽

P Value ◽

Growth Responses ◽

Fraxinus Americana ◽

Trunk Diameter ◽

Root Regrowth ◽

Planting Material ◽

Surrounding Soil ◽

Wire Basket

The topic of wire basket removal during planting remains an area of contention among nursery growers, landscapers, and arborists who work with balled-and-burlapped planting material. Those in favor of removal fear that the burlap and wire surrounding a tree’s root ball will impede root regrowth and eventually lead to the girdling of any roots that do penetrate into the surrounding soil. Those opposed to removal believe the advantages to tree and root system stability during transplanting and establishment outweigh any negatives to leaving the root ball intact. In 2008, 45 Fraxinus Americana ‘Autumn Purple’ were randomly assigned one of three transplanting treatments: 1) transplanted by tree spade without burlap/wire; 2) transplanted as balled-and-burlapped with only burlap and string removed; or 3) transplanted as balled-and-burlapped with all packaging materials (i.e., string, burlap, wire basket) removed. All trees survived regardless of treatment. In addition to survival, trunk diameter and tree height were measured annually for nine years. Marginal differences were noted for the two growth responses over the course of the trial (min P-value = 0.0599).

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Root system architectural and growth responses of crop plants to mineral nutrition under moisture stress and its implications in drought tolerance

10.1016/b978-0-12-816091-6.00008-0 ◽

2022 ◽

pp. 171-207

Author(s):

Kirti Bardhan ◽

Vipulkumar B. Parekh ◽

Suchismita Jena ◽

Sanket J. More ◽

Duwini Padukkage

Keyword(s):

Drought Tolerance ◽

Root System ◽

Mineral Nutrition ◽

Moisture Stress ◽

Crop Plants ◽

Growth Responses

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The tree height-related spatial variances of tree sap flux density and its scale-up to stand transpiration in a subtropical evergreen broadleaf forest

Ecohydrology ◽

10.1002/eco.1979 ◽

2018 ◽

Vol 11 (7) ◽

pp. e1979 ◽

Cited By ~ 5

Author(s):

Zhenzhen Zhang ◽

Ping Zhao ◽

Xiuhua Zhao ◽

Juan Zhou ◽

Peiqiang Zhao ◽

...

Keyword(s):

Flux Density ◽

Scale Up ◽

Tree Height ◽

Sap Flux ◽

Sap Flux Density ◽

Broadleaf Forest ◽

Stand Transpiration ◽

Tree Sap

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Modeling Early Responses of Loblolly Pine Growth to Thinning in the Western Gulf Coastal Plain Region

Forest Science ◽

10.1093/forsci/fxaa009 ◽

2020 ◽

Vol 66 (5) ◽

pp. 623-633

Author(s):

Y H Weng ◽

J Grogan ◽

D W Coble

Keyword(s):

Loblolly Pine ◽

Basal Area ◽

Tree Height ◽

Height Growth ◽

Growth Responses ◽

Individual Tree ◽

Large Trees ◽

The Difference ◽

Pinus Taeda L ◽

Stand Basal Area

Abstract Growth response to thinning has long been a research topic of interest in forest science. This study presents the first 3–4 years of response of loblolly pine (Pinus taeda L.) growth to thinning at different intensities. Data were collected from the East Texas Pine Research Project’s region-wide loblolly pine thinning study, which covers a wide variety of stand conditions. Four treatments, light, moderate, and heavy thinning, respectively having 370, 555, and 740 residual trees per hectare after thinning, and an unthinned control, were included. Individual tree diameter at breast height (dbh) and total height were recorded annually for the first 3–4 years after thinning. Results indicate significant differences between treatments in dbh growth in each year after thinning, as well as for all years combined. Each thinning treatment had significantly greater dbh growth than the control in the first growing season with this positive response being more evident in the case of the heavier thinning or at the later years post-thinning. Conversely, the thinning effect on tree height growth was initially negligibly negative, then becoming positive after 2–4 years, with the heavier thinning becoming positive sooner. Tree size class, assigned based on prethinning dbh, had a significant effect on both dbh and height growth responses. Compared to the control, small trees had a greater response both in dbh and in height growth than the medium and large trees over the measurement period. At the stand level, the heavier thinning had significantly less stand basal area per hectare, but the difference in stand basal area per hectare between the thinned and the unthinned plots decreased with years post-thinning. Results from this study can improve our understanding in thinning effects and help forest managers make accurate decisions on silvicultural regimes.

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Growth responses of Picea abies and Larix decidua to elevation in subalpine areas of Tyrol, Austria

Canadian Journal of Forest Research ◽

10.1139/x02-202 ◽

2003 ◽

Vol 33 (4) ◽

pp. 653-662 ◽

Cited By ~ 41

Author(s):

Mai He Li ◽

Jian Yang ◽

Norbert Kräuchi

Keyword(s):

Picea Abies ◽

Tree Growth ◽

Ground Surface ◽

Tree Height ◽

Larix Decidua ◽

Growth Responses ◽

Local Climate ◽

Subalpine Zone ◽

Tree Canopies ◽

Key Factor

Microsites related to microenvironmental conditions, including microclimate, seem to be a key factor for the restoration of forests in the subalpine area. Tree growth was studied in Picea abies (L.) Karst. (Norway spruce) and Larix decidua Mill. (European larch) on 30 plots located at different microsites (i.e., different elevations and micro top o graphies combined) within the subalpine zone (16801940 m) of the Schmirn Valley (Tyrol, Austria). The age of the trees studied was 27 years for larch and 28 years for spruce. The mean height and biomass growth decreased significantly with increasing elevation. The effect of elevation and microtopography on growth varied with tree size (age): (1) elevation had little effect on growth of trees less than 0.5 m in height; (2) both elevation and microtopography affected tree growth significantly when the tree height was between 0.5 and 3 m; (3) as trees exceed 3 m in height, tree canopies can fully cover the ground surface and create a forest microclimate causing growth to decline with increasing elevation, irrespective of microtopography. We conclude that the microclimate, associated with microsite, controls growth during the early stages of tree development, but following canopy closure, the local climate (mesoclimate) associated with topography begins to determine tree growth.

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ESTIMATION OF OPTIMAL CROWN COVERAGE AND CANOPY SHAPE FOR SHADOW ESTIMATION ON TROPICAL MOIST BROADLEAF FOREST

ISPRS Annals of Photogrammetry Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-annals-v-3-2021-211-2021 ◽

2021 ◽

Vol V-3-2021 ◽

pp. 211-217

Author(s):

T. Fujiwara ◽

W. Takeuchi

Keyword(s):

3D Model ◽

Gross Primary Production ◽

Tree Height ◽

Diurnal Variations ◽

Optimal Combination ◽

Physical Parameters ◽

Broadleaf Forest ◽

Voxel Model ◽

The Mean ◽

Sentinel 2

Abstract. Shadow fraction is essential for improving the estimation of gross primary production, but it is difficult to be observed by satellite due to the diurnal variations. Therefore, it is necessary to estimate the 3D model with physical parameters by simulating virtual forest reflectance. In this study, we aim to estimate the optimal combination of canopy shape and Crown Coverage (CC) through simulating virtual forests reflectance. First, satellite-derived Tree Height (TH) and CC for virtual forests were compared with the ones obtained by Canopy Hight Model (CHM). Second, virtual forests with different CC and canopy shapes were created, and the reflectance and shadow fraction were simulated. The canopy shape used were cylinder, ellipsoid, half-ellipsoid, and inverted half-ellipsoid. Finally, the simulated reflectance and shadow fraction were validated with Sentinel-2 reflectance and shadow fraction from voxel model. Our results show that the mean TH is 15 ± 2 m, and the CC was increased from 10% to 60% in 10% intervals. TH and CC obtained from the satellite had the Root Mean Square Error (RMSE) of 5m and 40%. Ellipsoid with 20% CC shows the lowest RMSE and the smallest discrepancy for shadow fractions at the same sun position. However, other combinations were more accurate in estimating mean daily shadow fraction. This would be caused by only one image adopted in validation, which could be improved by using multi-season images in the future.

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(452) Growth Responses of Salvia greggii and Dalea frutescens to Drought Stress

HortScience ◽

10.21273/hortsci.40.4.1036a ◽

2005 ◽

Vol 40 (4) ◽

pp. 1036A-1036

Author(s):

Genhua Niu ◽

Denise S. Rodriguez

Keyword(s):

Water Stress ◽

Drought Stress ◽

Drought Tolerance ◽

Water Potential ◽

Water Content ◽

Water Status ◽

Irrigation Management ◽

Growth Responses ◽

Shoot Number ◽

Dry Down

Salvia greggii (salvia) and Dalea frutescens (dalea) are two popular shrubs. However, little information is available on their drought tolerance. The objectives of this study were to investigate the effect of various degrees of water stress on growth and to characterize the dynamics of water relations to root substrate water content for developing best irrigation management. Salvia and dalea plants in 12-L plastic containers were grown in a greenhouse and pruned to one node at the base of the soft shoots for salvia or at the same height for dalea prior to the start of the experiment. There were three irrigation regimens: plants were irrigated daily (control), or irrigation was withheld until moderate or severe water stress signs exhibited. After several weeks of intermittent cyclic dry-down irrigation regimens, total shoot number per container was reduced by 40% to 50% for salvia and 35% to 40% for dalea. Average shoot length was reduced by 35% to 45% for salvia and 50% to 65% for dalea in moderate and severe stressed treatments compared to the control. Drought stress resulted in less shoot elongation and fewer new shoots in both species. To examine the relationship between plant water status and substrate water content, a dry down test was performed on five well-watered plants by withholding irrigation until midday water potential dropped to below –4 MPa. As substrate water contents in both species reached 8%, the predawn water potentials did not recover from the midday water potential of the previous day, indicating there was no available water in the substrate for roots to take up. The drought tolerance of these two species needs further study using various growing media.

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Early growth responses of blue gums on the basaltic plains to ripping, mounding and fertiliser application

Australian Journal of Experimental Agriculture ◽

10.1071/ea99113 ◽

2000 ◽

Vol 40 (7) ◽

pp. 987 ◽

Cited By ~ 3

Author(s):

R. R. Bird ◽

D. W. Jowett ◽

T. T. Jackson ◽

G. A. Kearney ◽

M. J. Waters ◽

...

Keyword(s):

Tree Height ◽

Seed Orchard ◽

Stem Volume ◽

First Year ◽

Growth Responses ◽

The Mean ◽

Fertiliser Application ◽

Western Victoria ◽

Source Site ◽

Nitrogen Phosphorus

The effect of ripping, mounding and fertiliser application on growth of E. globulus spp. globulus (Tasmanian blue gum) was assessed on 2 sites on the basaltic plains in south-western Victoria. The sites were gravelly loam duplex soils on a well-drained hillcrest and a clay–loam duplex soil on a valley flat that has impeded drainage in winter. The ground preparation treatments comprised a control (herbicide only), ripping to 65 cm, ripping plus small mounds (20 by 40 cm) and ripping plus large mound (60 by 150 cm). The fertiliser treatments were nil, 125, 250 and 500 g of fertiliser (nitrogen, phosphorus, potassium, sulfur) applied per tree 2 months after planting. The basal phosphorus, sulfur and potassium content of topsoil was 8–11, 11–14 and 140–220 mg/kg, respectively, for both sites. Rainfall in 1996, 1997 and 1998 was 695, 497 and 697 mm, respectively. This paper reports growth of 2 seedlots of blue gums (Yeodene Seed Orchard and Otway Ranges, Lorne) at 10 and 23 months after planting in Sep.–Oct. 1996 at 4 by 2 m spacing. The mean height of trees on the hillcrest site was 1.5 and 4.2 m at these times, respectively. For the valley flat, the mean heights were 0.9 and 3.0 m, respectively. On the hillcrest, ripping significantly increased tree height in the first year, but after 23 months neither height nor stem volume was greater than on unripped lines. Use of small mounds did not affect growth of trees at this site, whereas large mounds increased growth. At 10 months, tree height was greater (P<0.05) on the ripped plus large mounds than on the ripped only treatment, but this effect was lost at 23 months. Stem volume was 15% greater than on the ripped only treatment at 23 months, and 22% greater than the control. Trees from the Otway Ranges seedlot were taller and had 17% greater stem volume than trees from the Yeodene Seed Orchard seedlot at 23 months. For the valley flat, there were significant seedling source × site preparation interactions for height at 10 and 23 months (P<0.05), and for stem diameter and volume at 23 months (P<0.01), with the Otway seedlot performing better on the large mounds. There were no effects of fertiliser application on height, diameter or stem volume at 23 months on either site. The results indicate that planting on large mounds can improve early tree growth on farmland sites on the basaltic plains, but ripping without mounding, or fertiliser application in the first 2 years, is unlikely to improve performance.

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