Riparian plant species differ in sensitivity to both the mean and variance in groundwater stores

Abstract Aims Determining the ecological consequences of interactions between slow changes in long-term climate means and amplified variability in climate is an important research frontier in plant ecology. We combined the recent approach of climate sensitivity functions with a revised hydrological ‘bucket model’ to improve predictions on how plant species will respond to changes in the mean and variance of groundwater resources. Methods We leveraged spatiotemporal variation in long-term datasets of riparian vegetation cover and groundwater levels to build the first groundwater sensitivity functions for common plant species of dryland riparian corridors. Our results demonstrate the value of this approach to identifying which plant species will thrive (or fail) in an increasingly variable climate layered with declining groundwater stores. Important Findings Riparian plant species differed in sensitivity to both the mean and variance in groundwater levels. Rio Grande cottonwood (Populus deltoides ssp. wislizenii) cover was predicted to decline with greater inter-annual groundwater variance, while coyote willow (Salix exigua) and other native wetland species were predicted to benefit from greater year-to-year variance. No non-native species were sensitive to groundwater variance, but patterns for Russian olive (Elaeagnus angustifolia) predict declines under deeper mean groundwater tables. Warm air temperatures modulated groundwater sensitivity for cottonwood, which was more sensitive to variability in groundwater in years/sites with warmer maximum temperatures than in cool sites/periods. Cottonwood cover declined most with greater intra-annual coefficients of variation (CV) in groundwater, but was not significantly correlated with inter-annual CV, perhaps due to the short time series (16 years) relative to cottonwood lifespan. In contrast, non-native tamarisk (Tamarix chinensis) cover increased with both intra- and inter-annual CV in groundwater. Altogether, our results predict that changes in groundwater variability and mean will affect riparian plant communities through the differential sensitivities of individual plant species to mean versus variance in groundwater stores.

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Composition and dynamics of allochthonous organic matter inputs and benthic stock in a Brazilian stream

Marine and Freshwater Research ◽

10.1071/mf08247 ◽

2009 ◽

Vol 60 (10) ◽

pp. 990 ◽

Cited By ~ 39

Author(s):

Juliana Silva França ◽

Rener Silva Gregório ◽

Joana D'Arc de Paula ◽

José Francisco Gonçalves Júnior ◽

Fernando Alves Ferreira ◽

...

Keyword(s):

Organic Matter ◽

Plant Species ◽

Riparian Vegetation ◽

Seasonal Pattern ◽

Standing Stock ◽

Individual Plant ◽

Tropical Plants ◽

Composition And Structure ◽

The Mean ◽

Riparian Plant

Riparian vegetation provides the nutrient and energy input that maintains the metabolism and biodiversity in tropical headwater streams. In the present study, it was hypothesised that ~30% of riparian plant species contribute over 70% of coarse particulate organic matter and, because tropical plants are perennial and semi-deciduous, it was expected that leaf fall would occur year round. The aims of the present study were to evaluate the composition and structure of the plant riparian zone and the input and associated benthic stock of organic matter. The riparian vegetation was composed of 99 taxa. The most abundant plant species were Tapirira obtusa, Sclerolobium rugosum, Croton urucurana, Byrsonima sp. and Inga sp. The input and benthic stock showed a seasonal pattern, with higher values recorded at the end of the dry season and at the beginning of tropical storms. The biomass contributed monthly by the vegetation ranged from 28 ± 6 g m–2 to 38 ± 11 g m–2, and the mean monthly benthic standing stock was 138 ± 57 g m–2. The results illustrate the importance of riparian vegetation as an energy source to tropical streams and how individual plant species contribute to organic matter inputs in these ecosystems.

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Groundwater management based on monitoring of land subsidence and groundwater levels in the Kanto Groundwater Basin, Central Japan

Proceedings of the International Association of Hydrological Sciences ◽

10.5194/piahs-372-53-2015 ◽

2015 ◽

Vol 372 ◽

pp. 53-57 ◽

Cited By ~ 4

Author(s):

K. Furuno ◽

A. Kagawa ◽

O. Kazaoka ◽

T. Kusuda ◽

H. Nirei

Keyword(s):

Sea Level ◽

Groundwater Resources ◽

Sustainable Use ◽

Ground Subsidence ◽

Groundwater Levels ◽

Monitoring Wells ◽

Chiba Prefecture ◽

Groundwater Basin ◽

Term Monitoring

Abstract. Over 40 million people live on and exploit the groundwater resources of the Kanto Plain. The Plain encompasses metropolitan Tokyo and much of Chiba Prefecture. Useable groundwater extends to the base of the Kanto Plain, some 2500 to 3000 m below sea level. Much of the Kanto Plain surface is at sea level. By the early 1970s, with increasing urbanization and industrial expansion, local overdraft of groundwater resources caused major ground subsidence and damage to commercial and residential structures as well as to local and regional infrastructure. Parts of the lowlands around Tokyo subsided to 4.0 m below sea level; particularly affected were the suburbs of Funabashi and Gyotoku in western Chiba. In the southern Kanto Plain, regulations, mainly by local government and later by regional agencies, led to installation of about 500 monitoring wells and almost 5000 bench marks by the 1990's. Many of them are still working with new monitoring system. Long-term monitoring is important. The monitoring systems are costly, but the resulting data provide continuous measurement of the "health" of the Kanto Groundwater Basin, and thus permit sustainable use of the groundwater resource.

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Hydrological processes and water resources management in a dryland environment IV: Long-term groundwater level fluctuations due to variation in rainfall

Hydrology and Earth System Sciences ◽

10.5194/hess-3-353-1999 ◽

1999 ◽

Vol 3 (3) ◽

pp. 353-361 ◽

Cited By ~ 20

Author(s):

J. A. Butterworth ◽

R. E. Schulze ◽

L. P. Simmonds ◽

P. Moriarty ◽

F. Mugabe

Keyword(s):

Groundwater Resources ◽

Water Levels ◽

Shallow Aquifer ◽

Balance Model ◽

Specific Yield ◽

Evaporative Demand ◽

Groundwater Levels ◽

Groundwater Level Fluctuations ◽

Modelling Methods

Abstract. To evaluate the effects of variations in rainfall on groundwater, long-term rainfall records were used to simulate groundwater levels over the period 1953-96 at an experimental catchment in south-east Zimbabwe. Two different modelling methods were adopted. Firstly, a soil water balance model (ACRU) simulated drainage from daily rainfall and evaporative demand; groundwater levels were predicted as a function of drainage, specific yield and water table height. Secondly, the cumulative rainfall departure method was used to model groundwater levels from monthly rainfall. Both methods simulated observed groundwater levels over the period 1992-96 successfully, and long-term simulated trends in historical levels were comparable. Results suggest that large perturbations in groundwater levels area a normal feature of the response of a shallow aquifer to variations in rainfall. Long-term trends in groundwater levels are apparent and reflect the effect of cycles in rainfall. Average end of dry season water levels were simulated to be almost 3 m higher in the late 1970s compared to those of the early 1990s. The simulated effect of prolonged low rainfall on groundwater levels was particularly severe during the period 1981-92 with a series of low recharge years unprecedented in the earlier record. More recently, above average rainfall has resulted in generally higher groundwater levels. The modelling methods described may be applied in the development of guidelines for groundwater schemes to help ensure safe long-term yields and to predict future stress on groundwater resources in low rainfall periods; they are being developed to evaluate the effects of land use and management change on groundwater resources.

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Effects of salinisation on riparian plant communities in experimental catchments on the Collie River, Western Australia

Australian Journal of Botany ◽

10.1071/bt02119 ◽

2003 ◽

Vol 51 (6) ◽

pp. 667 ◽

Cited By ~ 24

Author(s):

A. J. Lymbery ◽

R. G. Doupé ◽

N. E. Pettit

Keyword(s):

Species Richness ◽

Plant Species ◽

Western Australia ◽

Soil Salinity ◽

Riparian Vegetation ◽

Plant Species Richness ◽

Perennial Herb ◽

Groundwater Levels ◽

Riparian Plant Communities ◽

Riparian Plant

Although the salinisation of streams has long been recognised as one of Western Australia's most serious environmental and resource problems, there is very little published information on the effects of salinisation on riparian flora and fauna. We studied riparian vegetation in three experimental catchments on the Collie River in Western Australia. The catchments are situated within a 5-km area of state forest and are geologically and botanically similar, but differ in the extent of clearing, groundwater levels and stream salinity. In each catchment, transects were taken perpendicular to the direction of streamflow, and 4-m2 quadrats taken along each transect. Within each quadrat, soil salinity was measured, all plants were identified to species level and percentage cover estimated. The catchments differed significantly in soil salinity, with salinity being greatest in the most extensively cleared catchment and increasing towards the floor of the valley. Plant-species richness, species diversity and species composition were significantly related to soil salinity, both among catchments and among quadrats within the most extensively cleared catchment. Plant-species richness and diversity decreased with increasing soil salinity, an effect that may be partly due to a decline in perennial herb and shrub species. This may have an impact on other components of the riparian ecosystem.

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Prediction of rates of inbreeding in selected populations

Genetics Research ◽

10.1017/s0016672300025180 ◽

1990 ◽

Vol 55 (1) ◽

pp. 41-54 ◽

Cited By ~ 97

Author(s):

Naomi R. Wray ◽

Robin Thompson

Keyword(s):

Selective Advantage ◽

Mass Selection ◽

Effective Population ◽

The Matrix ◽

Mean And Variance ◽

Unselected Population ◽

The Mean ◽

Number Of Individuals ◽

The Relationship

SummaryA method is presented for the prediction of rate of inbreeding for populations with discrete generations. The matrix of Wright's numerator relationships is partitioned into ‘contribution’ matrices which describe the contribution of the Mendelian sampling of genes of ancestors in a given generation to the relationship between individuals in later generations. These contributions stabilize with time and the value to which they stabilize is shown to be related to the asymptotic rate of inbreeding and therefore also the effective population size, where N is the number of individuals per generation and μr and are the mean and variance of long-term relationships or long-term contributions. These stabilized values are then predicted using a recursive equation via the concept of selective advantage for populations with hierarchical mating structures undergoing mass selection. Account is taken of the change in genetic parameters as a consequence of selection and also the increasing ‘competitiveness’ of contemporaries as selection proceeds. Examples are given and predicted rates of inbreeding are compared to those calculated in simulations. For populations of 20 males and 20, 40, 100 or 200 females the rate of inbreeding was found to increase by as much as 75% over the rate of inbreeding in an unselected population depending on mating ratio, selection intensity and heritability of the selected trait. The prediction presented here estimated the rate of inbreeding usually within 5% of that calculated from simulation.

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Models of long-term artificial selection in finite population with recurrent mutation

Genetics Research ◽

10.1017/s001667230002485x ◽

1986 ◽

Vol 48 (2) ◽

pp. 125-131 ◽

Cited By ~ 27

Author(s):

William G. Hill ◽

Jonathan Rasbash

Keyword(s):

Population Size ◽

First Generation ◽

Finite Population ◽

Effective Population ◽

Term Selection ◽

Cumulative Response ◽

Mean And Variance ◽

The Mean ◽

Selection For

SummaryThe effects of mutation on mean and variance of response to selection for quantitative traits are investigated. The mutants are assumed to be unlinked, to be additive, and to have their effects symmetrically distributed about zero, with absolute values of effects having a gamma distribution. It is shown that the ratio of expected cumulative response to generation t from mutants, , and expected response over one generation from one generation of mutants, , is a function of t/N, where t is generations and N is effective population size. Similarly, , is a function of t/N, where is the increment in genetic variance from one generation of mutants. The mean and standard deviation of response from mutations relative to that from initial variation in the population, in the first generation, are functions of . Evaluation of these formulae for a range of parameters quantifies the important role that population size can play in response to long-term selection.

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Impact of Climate Change on Groundwater Resources

Advances in Environmental Engineering and Green Technologies - Handbook of Research on Climate Change Impact on Health and Environmental Sustainability ◽

10.4018/978-1-4666-8814-8.ch010 ◽

2016 ◽

pp. 196-221 ◽

Cited By ~ 3

Author(s):

C. P. Kumar

Keyword(s):

Climate Change ◽

Water Resources ◽

Groundwater Resources ◽

Climate Variables ◽

Groundwater Levels ◽

Impact Of Climate Change ◽

Surface Water Resources ◽

The Impact ◽

The Relationship

Climate change poses uncertainties to the supply and management of water resources. While climate change affects surface water resources directly through changes in the major long-term climate variables such as air temperature, precipitation, and evapotranspiration, the relationship between the changing climate variables and groundwater is more complicated and poorly understood. The greater variability in rainfall could mean more frequent and prolonged periods of high or low groundwater levels, and saline intrusion in coastal aquifers due to sea level rise and resource reduction. This chapter presents the likely impact of climate change on groundwater resources and methodology to assess the impact of climate change on groundwater resources.

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Long-term warming results in species-specific shifts in seed mass in alpine communities

PeerJ ◽

10.7717/peerj.7416 ◽

2019 ◽

Vol 7 ◽

pp. e7416

Author(s):

Chunhui Zhang ◽

Zhen Ma ◽

Huakun Zhou ◽

Xinquan Zhao

Keyword(s):

Global Warming ◽

Plant Species ◽

Life History Theory ◽

Seed Mass ◽

Tibet Plateau ◽

Alpine Plant ◽

Trade Off ◽

The Mean ◽

Species Specific

Background Global warming can cause variation in plant functional traits due to phenotypic plasticity or rapid microevolutionary change. Seed mass represents a fundamental axis of trait variation in plants, from an individual to a community scale. Here, we hypothesize that long-term warming can shift the mean seed mass of species. Methods We tested our hypothesis in plots that had been warmed over 18 years in alpine meadow communities with a history of light grazing (LG) and heavy grazing (HG) on the Qinghai-Tibet plateau. In this study, seeds were collected during the growing season of 2015. Results We found that warming increased the mean seed mass of 4 (n = 19) species in the LG meadow and 6 (n = 20) species in the HG meadow, while decreasing the mean seed mass of 6 species in the LG and HG meadows, respectively. For 7 species, grazing history modified the effect of warming on seed mass. Therefore, we concluded that long-term warming can shift the mean seed mass at the species level. However, the direction of this variation is species-specific. Our study suggests that mean seed mass of alpine plant species appears to decrease in warmer (less stressful) habitats based on life-history theory, but it also suggests there may be an underlying trade-off in which mean seed mass may increase due to greater thermal energy inputs into seed development. Furthermore, the physical and biotic environment modulating this trade-off result in complex patterns of variation in mean seed mass of alpine plant species facing global warming.

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Contributions to groundwater from National Forest lands in the Mississippi Embayment: a century-long simulation

Water Practice & Technology ◽

10.2166/wpt.2020.098 ◽

2020 ◽

Author(s):

Ying Ouyang ◽

Theodor D. Leininger ◽

Sudhanshu S Panda ◽

Wayne C. Zipperer ◽

Timothy L. Stroope

Keyword(s):

Groundwater Resources ◽

National Forest ◽

Forest Land ◽

Groundwater Abstraction ◽

Mississippi Embayment ◽

Groundwater Levels ◽

Hydrologic Processes ◽

The Us ◽

Forest Lands

Abstract Very little effort has been devoted to analyzing the contributions of National Forests to groundwater resources in the US and around the world. In this study, the US Geological Survey's MERAS (Mississippi Embayment Regional Aquifer Study) model was used in the ModelMuse simulating system to estimate more than a century of subsurface hydrologic processes, groundwater budgets, and spatial-temporal groundwater level distributions in three forests in Mississippi, US. The results showed that groundwater recharge and stream leakage are important for groundwater storage in this region. All three forests served as groundwater sinks at times and sources at others, but the volume changes were relatively small. Groundwater levels declined over the simulation period – 1900 to 2014 – beneath all three forests, especially around the DNF (Delta National Forest) where groundwater abstraction is relatively intense. Knowledge gained from long-term hydrologic simulations and water budgets is useful when managing forest land groundwater resources.

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