scholarly journals Hydraulic acclimation in a Mediterranean oak subjected to permanent throughfall exclusion results in increased stem hydraulic capacitance

2020 ◽  
Vol 43 (6) ◽  
pp. 1528-1544
Author(s):  
Roberto L. Salomón ◽  
Kathy Steppe ◽  
Jean M. Ourcival ◽  
Selwyn Villers ◽  
Jesús Rodríguez‐Calcerrada ◽  
...  
Keyword(s):  
Hydraulic Capacitance ◽  
Throughfall Exclusion

scholarly journals A Novel Approach to Measure the Hydraulic Capacitance of a Microfluidic Membrane Pump

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Chun-Hui Wu ◽  
Chia-Wei Chen ◽  
Long-Sheng Kuo ◽  
Ping-Hei Chen
Keyword(s):  
Linear Correlation ◽  
Experimental Results ◽  
Membrane Thickness ◽  
Membrane Pump ◽  
Novel Approach ◽  
Hydraulic Capacitance ◽  
Linear And Nonlinear ◽  
Center Deflection ◽  
Membrane Deflection ◽  
Good Agreement

A novel approach was proposed to measure the hydraulic capacitance of a microfluidic membrane pump. Membrane deflection equations were modified from various studies to propose six theoretical equations to estimate the hydraulic capacitance of a microfluidic membrane pump. Thus, measuring the center deflection of the membrane allows the corresponding pressure and hydraulic capacitance of the pump to be determined. This study also investigated how membrane thickness affected the Young’s modulus of a polydimethylsiloxane (PDMS) membrane. Based on the experimental results, a linear correlation was proposed to estimate the hydraulic capacitance. The measured hydraulic capacitance data and the proposed equations in the linear and nonlinear regions qualitatively exhibited good agreement.

scholarly journals Change in hydraulic traits of Mediterranean Quercus ilex subjected to long-term throughfall exclusion

2010 ◽  
Vol 30 (8) ◽  
pp. 1026-1036 ◽  
Author(s):  
J.-M. Limousin ◽  
D. Longepierre ◽  
R. Huc ◽  
S. Rambal
Keyword(s):  
Quercus Ilex ◽  
Throughfall Exclusion

Responses of Soil Microbes to Hydrological Perturbations in Tropical Forest Soils

2021 ◽  
Author(s):  
Stephany S Chacon ◽  
Aizah Khurram ◽  
Markus Bill ◽  
Hans Bechtel ◽  
Jana Voriskova ◽  
...  
Keyword(s):  
Tropical Forest ◽  
Forest Soils ◽  
Climate Change Impacts ◽  
Cell Extracts ◽  
Microbial Response ◽  
Intact Soil Cores ◽  
Throughfall Exclusion ◽  
The Tropics ◽  
Meso Scale ◽  
Precipitation Cycles

<p>Model projections predict that climate change impacts on the tropics will include an increased frequency of drought and precipitation cycles. Such environmental fluctuations at the soil pore-scale play an important role in shaping microbial adaptive capacity, and trait composition of a community, which feeds back on to the breakdown and formation of soil organic matter (SOM). Understanding the factors controlling the carbon balance of humid tropical forest soils remains a social imperative. Microbial feedback to SOM pools is critical. Herein, we examine the microbial response to drought perturbations across  3 different, but complementary scales. At the largest scale, we explored the impacts of drought across a 1 m precipitation gradient spanning four sites from the Caribbean coast to the interior of Panama. At each site 4, throughfall exclusion plots (10 x 10 m) were established to reduce precipitation by 50 %. In addition, 4 corresponding control plots were also constructed. At the meso-scale, we incubated intact soil cores from one of these sites (P12) under 3 different hydrological treatments (control, drought, rewetting-drying cycles) for over a 5-month period. For the field and meso-scale experiments, we evaluated changes imparted by hydrological perturbations using multi-omic approaches, and physico-chemical measurements.   In order to identify the traits involved in response to drought at the field and meso-scale, we isolated a range of bacteria to subject to stress at the scale of the single-cell and simple communities.  Cell extracts were subjected to osmotic or matric stress and the short-term physiological responses determined using non-destructive synchrotron radiation-based Fourier Transform-Infrared spectromicroscopy. Through this approach, we identified changes in metabolic allocation within different cells, in particular to the secondary metabolome of the different bacteria. Our contribution will discuss the outcomes of these multi-scale experiments.  Specifically focusing on how shifts in the microbial community and physiological changes may influence tropical soil carbon stability under future scenarios of altered drought and precipitation cycles.</p>

Trade-offs between xylem water and carbohydrate storage among 24 coexisting subtropical understory shrub species spanning a spectrum of isohydry

2020 ◽  
Author(s):  
Peipei Jiang ◽  
Frederick C Meinzer ◽  
Xiaoli Fu ◽  
Liang Kou ◽  
Xiaoqin Dai ◽  
...  
Keyword(s):  
Photosynthetic Performance ◽  
Dry Season ◽  
Adaptation Strategies ◽  
Wet Season ◽  
Drought Adaptation ◽  
Drought Avoidance ◽  
Carbohydrate Storage ◽  
Trade Offs ◽  
Volume Curve ◽  
Hydraulic Capacitance

Abstract Hydraulic capacitance and carbohydrate storage are two drought adaptation strategies of woody angiosperms. However, we currently lack information on their associations and how they are associated with species’ degree of isohydry. We measured total stem xylem nonstructural carbohydrate (NSC) concentration in the dry and wet seasons, xylem hydraulic capacitance, native leaf water potentials, pressure–volume curve parameters and photosynthetic performance in 24 woody understory species differing in their degree of isohydry. We found a trade-off between xylem water and carbohydrate storage both in storage capacitance and along a spectrum of isohydry. Species with higher hydraulic capacitance had lower native NSC storage. The less isohydric species tended to show greater NSC depletion in the dry season and have more drought-tolerant leaves. In contrast, the more isohydric species had higher hydraulic capacitance, which may enhance their drought avoidance capacity. In these species, leaf flushing in the wet season and higher photosynthetic rates in the dry season resulted in accumulation rather than depletion of NSC in the dry season. Our results provide new insights into the mechanisms through which xylem storage functions determine co-occurring species’ drought adaptation strategies and improve our capacity to predict community assembly processes under drought.

scholarly journals VvPIP2;4Naquaporin involvement in controlling leaf hydraulic capacitance and resistance in grapevine

2016 ◽  
Vol 158 (3) ◽  
pp. 284-296 ◽  
Author(s):  
Marco Vitali ◽  
Hervé Cochard ◽  
Giorgio Gambino ◽  
Alexandre Ponomarenko ◽  
Irene Perrone ◽  
...  
Keyword(s):  
Hydraulic Capacitance

scholarly journals The ratio of transpiration to evapotranspiration in a rainfed maize field on the Loess Plateau of China

2016 ◽  
Vol 17 (1) ◽  
pp. 221-228 ◽  
Author(s):  
Shanshan Zhou ◽  
Wenzhao Liu ◽  
Wen Lin
Keyword(s):  
Linear Relationship ◽  
Loess Plateau ◽  
Flow Rate ◽  
Sap Flow ◽  
Crop Production ◽  
The Loess Plateau ◽  
Area Index ◽  
Hydraulic Capacitance ◽  
Weighing Method ◽  
Field Water Balance

Maize (Zea mays L.) is a major crop on the Loess Plateau, and calculating the ratio of transpiration to evapotranspiration (T/ET) of maize is important for estimating field water balance. In this study, the sap flow method was adopted to measure transpiration (T) characteristics of maize. In order to calibrate the sap flow gauge, the sap flow rate was compared to the leaf T determined by the weighing method. The sap flow value was measured per hour for 3 days and the mean of the hourly values for each day was taken as the daily value to avoid the influence of hydraulic capacitance. There was a significant linear relationship between leaf T and sap flow rate. The slope and intercept of linear regression were 0.764 and 4.944, with an R2 of 0.97 (p < 0.01). We also analyzed the T and ET of maize under field conditions. The T/ET of maize was 63.3% from July to September 2012. The T/ET and leaf area index had a good linear relationship. Partitioning of ET into soil evaporation (E) and T may have important implications for analyzing crop water use efficiency, evaluating the crop production potential of precipitation and optimizing field water management.

Effect of summer throughfall exclusion, summer drought, and winter snow cover on methane fluxes in a temperate forest soil

2006 ◽  
Vol 38 (6) ◽  
pp. 1388-1395 ◽  
Author(s):  
Werner Borken ◽  
Eric A. Davidson ◽  
Kathleen Savage ◽  
Eric T. Sundquist ◽  
Paul Steudler
Keyword(s):  
Snow Cover ◽  
Forest Soil ◽  
Temperate Forest ◽  
Summer Drought ◽  
Winter Snow ◽  
Methane Fluxes ◽  
Throughfall Exclusion

scholarly journals The effects of an experimental drought on the ecophysiology and fruiting phenology of a tropical rainforest palm

2020 ◽  
Vol 13 (6) ◽  
pp. 744-753
Author(s):  
Nara O Vogado ◽  
Michael J Liddell ◽  
Susan G W Laurance ◽  
Mason J Campbell ◽  
Alexander W Cheesman ◽  
...  
Keyword(s):  
Climate Change ◽  
Soil Moisture ◽  
Stomatal Conductance ◽  
Photosynthetic Rate ◽  
Tropical Rainforest ◽  
Future Climate Change ◽  
Fruiting Phenology ◽  
Physiological Processes ◽  
Throughfall Exclusion ◽  
The Impact

Abstract Aims Anthropogenic climate change is predicted to increase mean temperatures and rainfall seasonality. How tropical rainforest species will respond to this climate change remains uncertain. Here, we analysed the effects of a 4-year experimental throughfall exclusion (TFE) on an Australian endemic palm (Normambya normanbyi) in the Daintree rainforest of North Queensland, Australia. We aimed to understand the impact of a simulated reduction in rainfall on the species’ physiological processes and fruiting phenology. Methods We examined the fruiting phenology and ecophysiology of this locally abundant palm to determine the ecological responses of the species to drought. Soil water availability was reduced overall by ~30% under a TFE experiment, established in May 2015. We monitored monthly fruiting activity for 8 years in total (2009–2018), including 4 years prior to the onset of the TFE. In the most recent year of the study, we measured physiological parameters including photosynthetic rate, stomatal conductance and carbon stable isotopes (δ 13C, an integrated measure of water use efficiency) from young and mature leaves in both the dry and wet seasons. Important Findings We determined that the monthly fruiting activity of all palms was primarily driven by photoperiod, mean solar radiation and mean temperature. However, individuals exposed to lower soil moisture in the TFE decreased significantly in fruiting activity, photosynthetic rate and stomatal conductance. We found that these measures of physiological performance were affected by the TFE, season and the interaction of the two. Recovery of fruiting activity in the TFE palms was observed in 2018, when there was an increase in shallow soil moisture compared with previous years in the treatment. Our findings suggest that palms, such as the N. normanbyi, will be sensitive to future climate change with long-term monitoring recommended to determine population-scale impacts.

Sign in / Sign up

Export Citation Format

Share Document