Water availability and forest growth in coarse-textured soils

2011 ◽  
Vol 91 (2) ◽  
pp. 199-210 ◽  
Author(s):  
Mingbin Huang ◽  
S. Lee Barbour ◽  
Amin Elshorbagy ◽  
Julie Zettl ◽  
Bing Cheng Si

Huang, M., Barbour, S. L., Elshorbagy, A., Zettl, J. D. and Si, B. C. 2011. Water availability and forest growth in coarse-textured soils. Can. J. Soil Sci. 91: 199–210. A method of evaluating the influence of soil layering and climatic variability on plant available water for forest growth is presented. This method enables species-specific levels of maximum sustainable plant transpiration to be evaluated. A calibrated HYDRUS-1D model was used with a 60-yr meteorological record to simulate actual evapotransipration (ETa) of dominant tree species with different values of leaf area index (LAI) for three sites in northern Alberta. A probability distribution of ETa was developed for each case. The relationships between LAI, plant above-ground primary production (ANPP), and ETa were used to estimate the minimum water demand to support plant growth at specific sites. The developed frequency curves of ETa and the minimum water demand can be used to determine the maximum sustainable LAI and the risk associated with revegetating a particular site with a dominant tree species. The effect of different tree species on the minimum water demand and the maximum sustainable LAI was also illustrated. The results indicated that layering of coarse-textured soils can provide more plant available water and support a higher maximum sustainable LAI than homogeneous soils of a similar texture.

2012 ◽  
Vol 28 (5) ◽  
pp. 519-522 ◽  
Author(s):  
M. A. Sobrado

The landscape of the upper Rio Negro basin (North Amazon) exhibits distinctive habitats that are associated with differential soil characteristics and topographical conditions as well as species composition (Herrera et al. 1978). The mixed forests thrive on well-structured oxisols on slightly more elevated areas. The valleys with sandy podzols are occupied by the ‘Amazon caatinga’ complex with three distinct zones: the bottom valley and the gentle slopes, both of which have closed forests, and the sandy domes with open forests (‘bana’ or sclerophyllous forest; Breimer 1985). From the mixed forest towards the caatinga valley-slope-dome habitats, the leaf δ15N signatures become increasingly negative, suggesting a trend in N limitation in the same direction (Sobrado 2010). Thus, negative leaf δ15N signatures depleted in 15N compared with the soil indicate a very tight N cycle in all of the habitats. Water availability follows a similar pattern from the top of the oxisol towards the flooded valley bottom of the caatinga, with extreme water-table fluctuations in the sandy domes (Klinge 1978). Thus, parallel variation in nutrient and water availabilities exist in this area that are associated with soil characteristics and topography. Under such contrasting habitats, species-specific responses would be linked to particular conditions of the habitat at a local scale (Comita & Engelbrecht 2009, Engelbrecht et al. 2007). A number of studies in these habitats have shown that this is the case for soil fertility (Coomes 1997, Medina et al. 1990, Sobrado 2010, Sobrado & Medina 1980). Similarly, the hydraulic characteristics and long-term water use are species specific and related to particular conditions of the habitat at the local scale (Sobrado 2010). In this report, it was hypothesized that the leaf tissue water relations of species thriving in different habitats may reflect the water availability at the particular sites as well. The leaf tissue water relations of species thriving in the extreme nutrient and water-supply conditions of the sandy domes from the caatinga complex have been previously studied in detail (Sobrado 2009a). However, these data are currently not available for the species that thrive in the surrounding area of the closed forests, and importantly, such information would allow for a comparison across habitats. Therefore, the present study assessed the minimum leaf water potential (midday) under field conditions as well as the leaf tissue water relations by using pressure-volume analysis of dominant tree species in the top canopy of these high-stature forests.


1993 ◽  
Vol 44 (6) ◽  
pp. 1389 ◽  
Author(s):  
SE Ockerby ◽  
DJ Lyons ◽  
GD Keefer ◽  
FPC Blamey ◽  
DF Yule

Four irrigation frequencies and six nitrogen (N) fertilizer rates (0-300 kg ha-1) were applied to cotton (Gossypium hirsutum L.) grown on three Vertisols in the Emerald Irrigation Area, central Queensland. The purpose was to describe lint production responses to the plant available water before irrigation and N fertilizer, in terms of the crop N content and the efficiency of crop N use for lint production. Lint yield was greatest when the plant available water before irrigation was 50-80010 of the plant available water capacity (PAWC) of each soil. The rate of N fertilizer for maximum yield varied with plant available water and soil type. Plant available water before irrigation >60% and <37% PAWC, and rain after irrigation reduced the crop N content at the time of maximum leaf area index. Relative yield generally responded to 130 kg crop N ha-', although the range from 101 to 141 kg crop N ha-1 reflected differences in the maximum yield of each treatment. If the crop N was <130 kg ha-1, yield was mostly determined by the crop N content, whereas if the crop N content was >130 kg ha-1, yield and the efficiency of crop N use for lint production was determined by the plant available water before irrigation and soil type. Nitrogen fertilizer strategies to achieve the maximum yield of cotton (var. Deltapine 61) should focus on obtaining 130 kg crop N ha-1. This crop N content produced maximum yields for a range of plant available water contents before irrigation, and for three soil types.


2015 ◽  
Vol 12 (9) ◽  
pp. 2773-2790 ◽  
Author(s):  
J. Guillemot ◽  
N. K. Martin-StPaul ◽  
E. Dufrêne ◽  
C. François ◽  
K. Soudani ◽  
...  

Abstract. The extent to which wood growth is limited by carbon (C) supply (i.e. source control) or by cambial activity (i.e. sink control) will strongly determine the responses of trees to global changes. Nevertheless, the physiological processes that are responsible for limiting forest growth are still a matter of debate. The aim of this study was to evaluate the key determinants of the annual C allocation to wood along large soil and climate regional gradients over France. The study was conducted for five tree species representative of the main European forest biomes (Fagus sylvatica, Quercus petraea, Quercus ilex, Quercus robur and Picea abies). The drivers of stand biomass growth were assessed on both inter-site and inter-annual scales. Our data set comprised field measurements performed at 49 sites (931 site-years) that included biometric measurements and a variety of stand characteristics (e.g. soil water holding capacity, leaf area index). It was complemented with process-based simulations when possible explanatory variables could not be directly measured (e.g. annual and seasonal tree C balance, bioclimatic water stress indices). Specifically, the relative influences of tree C balance (source control), direct environmental control (water and temperature controls of sink activity) and allocation adjustments related to age, past climate conditions, competition intensity and soil nutrient availability on growth were quantified. The inter-site variability in the stand C allocation to wood was predominantly driven by age-related decline. The direct effects of temperature and water stress on sink activity (i.e. effects independent from their effects on the C supply) exerted a strong influence on the annual stand wood growth in all of the species considered, including deciduous temperate species. The lagged effect of the past environmental conditions (e.g. the previous year's water stress and low C uptake) significantly affected the annual C allocation to wood. The C supply appeared to strongly limit growth only in temperate deciduous species. We provide an evaluation of the spatio-temporal dynamics of the annual C allocation to wood in French forests. Our study supports the premise that the growth of European tree species is subject to complex control processes that include both source and sink limitations. The relative influences of the growth drivers strongly vary with time and across spatial ecological gradients. We suggest a straightforward modelling framework with which to implement these combined forest growth limitations into terrestrial biosphere models.


2020 ◽  
Vol 3 (1) ◽  
pp. 49
Author(s):  
Edgaras Linkevičius ◽  
Gerda Junevičiūtė

Climate change and warming will potentially have profound effects on forest growth and yield, especially for pure stands in the near future. Thus, increased attention has been paid to mixed stands, e.g., pine and beech mixtures. However, the interaction of tree species growing in mixtures still remains unknown. Thus, the aim of this study was to investigate the impact of the interspecific and intraspecific competition to diameter, height, and crown width of pine and beech trees growing in mixtures, as well as to evaluate the impact of climatic indicators to the beech radial diameter increment. The data was collected in 2017 at the mixed mature pine beech double layer stand, located in the western part of Lithuania. The sample plot of 1.2 hectare was established and tree species, diameter at the breast height, tree height, height-to-crown base, height-to-crown width, and position were measured for all 836 trees. Additionally, a representative sample of radial diameter increments were estimated only for the beech trees by taking out core discs at the height of 1 m when the stand was partially cut. Competition analysis was based on the distance-dependent competition index, which was further based on crown parameters. Climatic effect was evaluated using classification and regression tree (CART) analysis. We found almost no interspecific competition effect to diameter, height, or crown width for both tree species growing in the first layer. However, it had an effect on beeches growing in the second layer. The intraspecific competition effect was important for pine and beech trees, showing a negative effect for both of them. Our results show the possible coexistence of these tree species due to niche differentiation. An analysis of climatic indicators from 1991–2005 revealed that precipitation from February–May of the current vegetation year and mean temperatures from July to September expressed radial diameter increment effects for beech trees. Low temperatures during March and April, as well as high precipitation during January, had a negative effect on beech radial increments. From 2006–2016, the highest effect on radial diameter increments was the mean temperatures from July to September, as well as the precipitation in January of the current year. From 1991–2016, the highest effect on radial diameter increments was the temperature from July to September 1991–2016 and the precipitation in June 1991–2016. Generally, cool temperatures and higher precipitation in June had a positive effect on beech radial increments. Therefore, our results show a sensitivity to high temperatures and droughts during summer amid Lithuanian’s growth conditions.


2021 ◽  
Vol 13 (2) ◽  
pp. 303
Author(s):  
Shi Hu ◽  
Xingguo Mo

Using the Global Land Surface Satellite (GLASS) leaf area index (LAI), the actual evapotranspiration (ETa) and available water resources in the Mekong River Basin were estimated with the Remote Sensing-Based Vegetation Interface Processes Model (VIP-RS). The relative contributions of climate variables and vegetation greening to ETa were estimated with numerical experiments. The results show that the average ETa in the entire basin increased at a rate of 1.16 mm year−2 from 1980 to 2012 (36.7% of the area met the 95% significance level). Vegetation greening contributed 54.1% of the annual ETa trend, slightly higher than that of climate change. The contributions of air temperature, precipitation and the LAI were positive, whereas contributions of solar radiation and vapor pressure were negative. The effects of water supply and energy availability were equivalent on the variation of ETa throughout most of the basin, except the upper reach and downstream Mekong Delta. In the upper reach, climate warming played a critical role in the ETa variability, while the warming effect was offset by reduced solar radiation in the Mekong Delta (an energy-limited region). For the entire basin, the available water resources showed an increasing trend due to intensified precipitation; however, in downstream areas, additional pressure on available water resources is exerted due to cropland expansion with enhanced agricultural water consumption. The results provide scientific basis for practices of integrated catchment management and water resources allocation.


Water ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2009
Author(s):  
Caroline Ednah Mwebaze ◽  
Jackson-Gilbert Mwanjalolo Majaliwa ◽  
Joshua Wanyama ◽  
Geoffrey Gabiri

Limited studies in East Africa and particularly in Uganda have been carried out to determine and map water use and demands. This study aimed at assessing the impact of management options on sustainable water allocation in environmentally sensitive catchments of Mubuku and Sebwe of Lake Edward-George basin in Western Uganda. We used hydro-meteorological data analysis techniques to quantify the available water. We applied Mike Hydro model to allocate water to the different ongoing developments in the catchment based on 2015 and 2040 water demand management scenarios. We used the Nile Basin Decision Support System to assess the sustainability of the different water management scenarios for sustainable water resources use. Reliability computation did not consider hydropower in this study. Results show that water available in 2015 was 60 MCM/YR and 365 MCM/YR for Sebwe and Mubuku, respectively and is projected to decrease by 15% and 11% by the year 2040 under climate scenario RCP8.5. We project water demand to rise by 64% for domestic, 44% for livestock, 400% for industry, 45% for hydro power and 66% for irrigation by 2040. Mubuku water demand is projected to increase from 5.2 MCM in 2015 to 10.7 MCM in 2040. Mubuku available water is projected to fall from 364.8 to 329.8 MCM per annum. Sebwe water demand is projected to increase from 9.7 MCM in 2015 to 22.2 MCM in 2040 and its available water is projected to fall from 60 to 52 MCM per annum by the year 2040 from 2015. Water managers ought to allocate water based on the reliable water allocation which prioritizes domestic and environmental water demands, allocates 90% of industrial demand, 70% of irrigation and 60% of livestock demand. We recommend institutionalizing this model to guide water allocation in the Mubuku-Sebwe sub catchments. Water users should employ more efficient water use techniques to achieve high reliability and sustainable water resources management.


1995 ◽  
Vol 12 (3) ◽  
pp. 115-120 ◽  
Author(s):  
David B. Kittredge ◽  
P. Mark S. Ashton

Abstract Browsing preferences by white-tailed deer were evaluated for 6 tree species in northeastern Connecticut. Deer density averaged 23/mile². Deer exhibited no species-specific preferences for seedlings greater than 19 in. For seedlings less than 19 in., hemlock and black birch were preferred. Red maple, sugar maple, and white pine seedlings were avoided. Red oak seedlings were neither preferred nor avoided. A much higher proportion of seedlings greater than 19.7 in. in height was browsed, regardless of species. Browsing preferences for species in the smaller seedling class, combined with a lack of preference for species in the larger class may result in future stands with less diverse tree species composition. Deer densities in excess of 23/mile² may be incompatible with regeneration of diverse forests in southern New England. North. J. Appl. For. 12(3):115-120.


Sign in / Sign up

Export Citation Format

Share Document