Seasonal water use by deciduous and evergreen woody species in a scrub community is based on water availability and root distribution

The seasonal water requirements of irrigated grain sorghum, the interaction between water use and applied N fertilizer, and the comparative water use efficiences of sorghum and barley were determined in southern Alberta over a 3-yr period. Peak daily water use of 6 mm for sorghum was 1 mm lower than that determined previously for barley. Seasonal water use (500 mm) was 20% greater than for barley because of sorghum’s longer growing season. Under adequate irrigation, both sorghum and barley responded linearly to applied N up to 80 kg/ha, but when water was restricted, sorghum showed less response than barley. Water-use efficiency (kg of grain/m3 of water used) decreased for both crops with increasing water availability but maximum yields were achieved under irrigation. When sorghum was favored with a long, warm growing season, it produced as much grain (6900 kg/ha) and used water as efficiently (1.25 kg/m3) as did barley.

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Water Availability--The Connection Between Water Use and Quality

Fact Sheet ◽

10.3133/fs20083015 ◽

2008 ◽

Author(s):

Robert M. Hirsch ◽

Pixie A. Hamilton ◽

Timothy L. Miller ◽

Donna N. Myers

Keyword(s):

Water Use ◽

Water Availability

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Root distribution and water use in coffee shaded with Tabebuia rosea Bertol. and Simarouba glauca DC. compared to full sun coffee in sub-optimal environmental conditions

Agroforestry Systems ◽

10.1007/s10457-015-9820-z ◽

2015 ◽

Vol 89 (5) ◽

pp. 857-868 ◽

Cited By ~ 18

Author(s):

M. P. Padovan ◽

V. J. Cortez ◽

L. F. Navarrete ◽

E. D. Navarrete ◽

A. C. Deffner ◽

...

Keyword(s):

Water Use ◽

Environmental Conditions ◽

Root Distribution ◽

Simarouba Glauca ◽

Tabebuia Rosea

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Intensified Interspecific Competition for Water after Afforestation with Robinia pseudoacacia into a Native Shrubland in the Taihang Mountains, Northern China

Sustainability ◽

10.3390/su13020807 ◽

2021 ◽

Vol 13 (2) ◽

pp. 807

Author(s):

Wanrui Zhu ◽

Wenhua Li ◽

Peili Shi ◽

Jiansheng Cao ◽

Ning Zong ◽

...

Keyword(s):

Soil Water ◽

Introduced Species ◽

Water Use ◽

Rainy Season ◽

Robinia Pseudoacacia ◽

Water Source ◽

Total Water ◽

Mountainous Areas ◽

Water Competition ◽

Seasonal Water Use

Understanding how soil water source is used spatiotemporally by tree species and if native species can successfully coexist with introduced species is crucial for selecting species for afforestation. In the rocky mountainous areas of the Taihang Mountains, alien Robinia pseudoacacia L. has been widely afforested into the native shrublands dominated by Ziziphus jujuba Mill var. spinosa and Vitex negundo L. var. heterophylla to improve forest coverage and soil nutrients. However, little is known about the water relation among species, especially seasonal water use sources in different microsites. We selected the soil and plant xylem samples of two opposite microtopographic sites (ridge and valley) monthly in the growth season to analyze isotope composition. The proportions of water sources were quantified by the MixSIAR model and compared pairwise between species, microsites and seasons. We found that deep subsoil water at a depth of 40–50 cm contributed up to 50% of the total water uptake for R. pseudoacacia and Z. jujuba in the growing season, indicating that they stably used deeper soil water and had intense water competition. However, V. negundo had a more flexible water use strategy, which derived more than 50% of the total water uptake from the soil layer of 0–10 cm in the rainy season, but majorly captured soil water at a depth of 30–50 cm in the dry season. Therefore, high niche overlaps were shown in V. negundo with the other two species in the dry season, but niche segregation was seen in the rainy season. The microtopographic sites did not shift the seasonal dynamic of the water source use patterns of the three studied species, but the water use niche overlap was higher in the valley than in the ridge. Taken together, the introduced species R. pseudoacacia intensified water competition with the native semi-arbor species Z. jujuba, but it could commonly coexist with the native shrub species V. negundo. Therefore, our study on seasonal water use sources in different microsites provides insight into species interaction and site selection for R. pseudoacacia afforestation in the native shrub community in rocky mountainous areas. It is better to plant R. pseudoacacia in the shrubland in the valley so as to avoid intense water competition and control soil erosion.

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How downstream sub-basins depend on upstream inflows to avoid scarcity: typology and global analysis of transboundary rivers

Hydrology and Earth System Sciences ◽

10.5194/hess-22-2795-2018 ◽

2018 ◽

Vol 22 (5) ◽

pp. 2795-2809 ◽

Cited By ~ 12

Author(s):

Hafsa Ahmed Munia ◽

Joseph H. A. Guillaume ◽

Naho Mirumachi ◽

Yoshihide Wada ◽

Matti Kummu

Keyword(s):

Water Stress ◽

Water Use ◽

Water Availability ◽

Water Scarcity ◽

Management Practices ◽

Global Analysis ◽

Water Shortage ◽

River Basins ◽

Analytical Framework ◽

Available Water

Abstract. Countries sharing river basins are often dependent upon water originating outside their boundaries; meaning that without that upstream water, water scarcity may occur with flow-on implications for water use and management. We develop a formalisation of this concept drawing on ideas about the transition between regimes from resilience literature, using water stress and water shortage as indicators of water scarcity. In our analytical framework, dependency occurs if water from upstream is needed to avoid scarcity. This can be diagnosed by comparing different types of water availability on which a sub-basin relies, in particular local runoff and upstream inflows. At the same time, possible upstream water withdrawals reduce available water downstream, influencing the latter water availability. By developing a framework of scarcity and dependency, we contribute to the understanding of transitions between system regimes. We apply our analytical framework to global transboundary river basins at the scale of sub-basin areas (SBAs). Our results show that 1175 million people live under water stress (42 % of the total transboundary population). Surprisingly, the majority (1150 million) of these currently suffer from stress only due to their own excessive water use and possible water from upstream does not have impact on the stress status – i.e. they are not yet dependent on upstream water to avoid stress – but could still impact on the intensity of the stress. At the same time, 386 million people (14 %) live in SBAs that can avoid stress owing to available water from upstream and have thus upstream dependency. In the case of water shortage, 306 million people (11 %) live in SBAs dependent on upstream water to avoid possible shortage. The identification of transitions between system regimes sheds light on how SBAs may be affected in the future, potentially contributing to further refined analysis of inter- and intrabasin hydro-political power relations and strategic planning of management practices in transboundary basins.

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Dry matter yield and water use efficiency of five perennial subtropical grasses at four levels of water availability

African Journal of Range and Forage Science ◽

10.2989/10220110609485900 ◽

2006 ◽

Vol 23 (3) ◽

pp. 165-169 ◽

Cited By ~ 3

Author(s):

D Marais ◽

N Rethman ◽

J Annandale

Keyword(s):

Water Use Efficiency ◽

Water Use ◽

Water Availability ◽

Dry Matter ◽

Dry Matter Yield ◽

Use Efficiency ◽

Four Levels

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Modelling global water stress of the recent past: on the relative importance of trends in water demand and climate variability

Hydrology and Earth System Sciences ◽

10.5194/hess-15-3785-2011 ◽

2011 ◽

Vol 15 (12) ◽

pp. 3785-3808 ◽

Cited By ~ 169

Author(s):

Y. Wada ◽

L. P. H. van Beek ◽

M. F. P. Bierkens

Keyword(s):

Water Stress ◽

Climate Variability ◽

Water Use ◽

Extreme Events ◽

Water Availability ◽

Water Scarcity ◽

Water Demand ◽

Developing Economies ◽

Blue Water ◽

Global Population

Abstract. During the past decades, human water use has more than doubled, yet available freshwater resources are finite. As a result, water scarcity has been prevalent in various regions of the world. Here, we present the first global assessment of past development of water stress considering not only climate variability but also growing water demand, desalinated water use and non-renewable groundwater abstraction over the period 1960–2001 at a spatial resolution of 0.5°. Agricultural water demand is estimated based on past extents of irrigated areas and livestock densities. We approximate past economic development based on GDP, energy and household consumption and electricity production, which are subsequently used together with population numbers to estimate industrial and domestic water demand. Climate variability is expressed by simulated blue water availability defined by freshwater in rivers, lakes, wetlands and reservoirs by means of the global hydrological model PCR-GLOBWB. We thus define blue water stress by comparing blue water availability with corresponding net total blue water demand by means of the commonly used, Water Scarcity Index. The results show a drastic increase in the global population living under water-stressed conditions (i.e. moderate to high water stress) due to growing water demand, primarily for irrigation, which has more than doubled from 1708/818 to 3708/1832 km3 yr−1 (gross/net) over the period 1960–2000. We estimate that 800 million people or 27% of the global population were living under water-stressed conditions for 1960. This number is eventually increased to 2.6 billion or 43% for 2000. Our results indicate that increased water demand is a decisive factor for heightened water stress in various regions such as India and North China, enhancing the intensity of water stress up to 200%, while climate variability is often a main determinant of extreme events. However, our results also suggest that in several emerging and developing economies (e.g. India, Turkey, Romania and Cuba) some of past extreme events were anthropogenically driven due to increased water demand rather than being climate-induced.

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Ecological Factors Preventing Restoration of Degraded Short Tussock Landscapes in New Zealand’s Dryland Zone

Open Agriculture ◽

10.1515/opag-2017-0048 ◽

2017 ◽

Vol 2 (1) ◽

Author(s):

Anna P. Rodrigues ◽

Elena Moltchanova ◽

David A. Norton ◽

Matthew Turnbull

Keyword(s):

Water Availability ◽

Ecological Factors ◽

Woody Species ◽

Biotic Factors ◽

Introduced Herbivores ◽

Physical Chemical ◽

Native Woody Species ◽

Dryland Ecosystems ◽

Survival And Growth ◽

Chemical Conditions

AbstractBiotic factors such as the presence of invasive animal and/or plant species are well known as major causes of ecological degradation and as limiting either natural or assisted (human-induced) ecological restoration. However, abiotic aspects of the landscape, such as water availability and soil physical/chemical conditions can also potentially limit restoration and should be considered. Dryland ecosystems are amongst the world’s most threatened and least protected. New Zealand’s drylands have been drastically changed, initially through burning, agricultural and grazing practices and the impacts of introduced herbivores and plants. This research aimed at identifying some of the key environmental factors preventing the reestablishment of native woody species in a New Zealand dryland ecosystem. The experiments involved a combination of shading, irrigation and grazing exclusion. The results showed that supplemental water was not beneficial for the survival and growth of the native seedlings, unless combined with shade. Fencing proved important for establishment, even though the species used are regarded in the literature as unpalatable to herbivores. The results indicated that the presence of shade was fundamental for the establishment and growth of the native seedlings likely due to improvements in the microclimate, soil aeration, and water availability to seedlings.

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Apparent Tolerance of Low Water Availability in Temperate Asian Bamboos1

Journal of Environmental Horticulture ◽

10.24266/jeh-d-17-00009.1 ◽

2018 ◽

Vol 36 (1) ◽

pp. 7-13

Author(s):

Melissa C. Smith ◽

Richard N. Mack

Keyword(s):

Stomatal Conductance ◽

Water Use Efficiency ◽

Water Use ◽

North American ◽

Water Availability ◽

Irrigation Treatment ◽

Bamboo Species ◽

Intrinsic Water Use Efficiency ◽

Use Efficiency ◽

Pleioblastus Chino

Abstract Suitable plant water dynamics and the ability to withstand periods of low moisture input facilitate plant establishment in seasonally arid regions. Temperate bamboos are a major constituent of mixed evergreen and deciduous forests throughout temperate East Asia but play only an incidental role in North American forests and are altogether absent in the Pacific Northwest forest. Many bamboo species are classified as mesic or riparian, but none are considered drought tolerant. To assess their ability to withstand low water, we subjected five Asian temperate and one North American temperate bamboo species to three irrigation treatments: 100%, 50%, and 10% replacement of water lost through evapotranspiration. Plants were irrigated every four days over a 31-day period. Plant response to treatments was measured with stomatal conductance, leaf xylem water potentials, and intrinsic water use efficiency (iWUE). Pleioblastus distichus and Pseudosasa japonica showed significant reductions in conductance between high and low irrigation treatments. Sasa palmata had significantly lower stomatal conductance in all treatments. Pleioblastus chino displayed significantly higher iWUE in the mid irrigation treatment and Arunindaria gigantea displayed significantly lower iWUE than P. chino and S. palmata in the low irrigation treatment. The Asian bamboo species examined here tolerate low water availability and readily acclimate to different soil moisture conditions. Index words: Temperate bamboos, irrigation response, stomatal conductance, intrinsic water use efficiency. Species used in this study: Giant Cane [Arundinaria gigantea (Walt.) Muhl.]; Pleioblastus chino (Franchet & Savatier) Makino; Pleioblastus distichus (Mitford) Nakai; Pseudosasa japonica (Makino); Sasa palmata (Bean) Nakai.

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