Characterizing Growing Season Length of Subtropical Coniferous Forests with a Phenological Model

Understanding plant phenological change is of great concern in the context of global climate change. Phenological models can aid in understanding and predicting growing season changes and can be parameterized with gross primary production (GPP) estimated using the eddy covariance (EC) technique. This study used nine years of EC-derived GPP data from three mature subtropical longleaf pine forests in the southeastern United States with differing soil water holding capacity in combination with site-specific micrometeorological data to parameterize a photosynthesis-based phenological model. We evaluated how weather conditions and prescribed fire led to variation in the ecosystem phenological processes. The results suggest that soil water availability had an effect on phenology, and greater soil water availability was associated with a longer growing season (LOS). We also observed that prescribed fire, a common forest management activity in the region, had a limited impact on phenological processes. Dormant season fire had no significant effect on phenological processes by site, but we observed differences in the start of the growing season (SOS) between fire and non-fire years. Fire delayed SOS by 10 d ± 5 d (SE), and this effect was greater with higher soil water availability, extending SOS by 18 d on average. Fire was also associated with increased sensitivity of spring phenology to radiation and air temperature. We found that interannual climate change and periodic weather anomalies (flood, short-term drought, and long-term drought), controlled annual ecosystem phenological processes more than prescribed fire. When water availability increased following short-term summer drought, the growing season was extended. With future climate change, subtropical areas of the Southeastern US are expected to experience more frequent short-term droughts, which could shorten the region’s growing season and lead to a reduction in the longleaf pine ecosystem’s carbon sequestration capacity.

Download Full-text

Effects of climate change on evapotranspiration and soil water availability in Norway spruce forests in southern Finland: an ecosystem model based approach

Ecohydrology ◽

10.1002/eco.276 ◽

2011 ◽

Vol 6 (1) ◽

pp. 51-63 ◽

Cited By ~ 13

Author(s):

Zhen-Ming Ge ◽

Seppo Kellomäki ◽

Xiao Zhou ◽

Kai-Yun Wang ◽

Heli Peltola ◽

...

Keyword(s):

Climate Change ◽

Soil Water ◽

Norway Spruce ◽

Water Availability ◽

Ecosystem Model ◽

Soil Water Availability ◽

Spruce Forests ◽

Model Based

Download Full-text

Effects of short-term ozone exposure and soil water availability on the carbon economy of juvenile Douglas-fir

Tree Physiology ◽

10.1093/treephys/14.6.647 ◽

1994 ◽

Vol 14 (6) ◽

pp. 647-657 ◽

Cited By ~ 17

Author(s):

A. Gorissen ◽

N. N. Joosten ◽

S. M. Smeulders ◽

J. A. van Veen

Keyword(s):

Soil Water ◽

Water Availability ◽

Douglas Fir ◽

Ozone Exposure ◽

Soil Water Availability ◽

Short Term ◽

Carbon Economy

Download Full-text

Modeling Productivity in Mangrove Forests as Impacted by Effective Soil Water Availability and Its Sensitivity to Climate Change Using Biome-BGC

Ecosystems ◽

10.1007/s10021-010-9365-y ◽

2010 ◽

Vol 13 (7) ◽

pp. 949-965 ◽

Cited By ~ 17

Author(s):

Zhongkui Luo ◽

Osbert Jianxin Sun ◽

Enli Wang ◽

Hai Ren ◽

Hualin Xu

Keyword(s):

Climate Change ◽

Soil Water ◽

Water Availability ◽

Soil Water Availability ◽

Mangrove Forests

Download Full-text

Differences in the environmental control of leaf senescence of four Quercus species coexisting in a Mediterranean environment

Forest Systems ◽

10.5424/fs/2015242-07263 ◽

2015 ◽

Vol 24 (2) ◽

pp. e027

Author(s):

Teresa Del Río García ◽

Sonia Mediavilla ◽

Fernando Silla ◽

Alfonso Escudero

Keyword(s):

Climate Change ◽

Environmental Factors ◽

Soil Water ◽

Leaf Senescence ◽

Water Availability ◽

Mortality Rates ◽

Soil Water Availability ◽

Deciduous Species ◽

Evergreen Species ◽

N Resorption

Aims of study: Our aim is to check the effect of different environmental factors on the leaf senescence of four Quercus species with different leaf longevities, to help us better understand the implications of climate change on leaf demography.Area of study: The study was carried out in two sites of theprovince of Salamanca (central-westernSpain), both sites showing differences in their temperatures and soil water availability.Material and Methods: Over four years (2007-2010) we monitored the number of leaves of the different cohorts labelled on five specimens of each species at both sites to elaborate life-tables and calculate mortality rates. Mortality rates were then related to several other variables measured during the same period: air temperature, soil water availability, precipitation, predawn water potentials (Ypd) and leaf N resorption.Main results: In the two deciduous species maximum daily temperatures and the time during which their values remain above a certain threshold (between 11 and12ºC of maximum daily temperature) are the main factors controlling the timing of leaf abscission. In the evergreen species abscission of old leaves showed no relationship with the environmental factors analyzed. By contrast, mortality rates of old leaves were related to seasonal N resorption values, with the maximum mortality of old leaves coinciding in time with the maximum withdrawal of N from shed leaves and also with the emergence of the new leaf cohort.Research highlights: The increase in the duration of the leaves of the two deciduous species, as a result of the delayed senescence by warmer autumnal temperatures, could contribute to reducing the differences in the length of the productive leaf life with respect to the evergreen species. This could improve the competitive capacity of deciduous species as opposed to that of evergreen species, and thus alter their respective distribution patterns.Keywords: climate change; deciduous; evergreen; leaf abscission; temperature; water availability.

Download Full-text

Response of lentil to high temperature under variable water supply and carbon dioxide enrichment

Crop and Pasture Science ◽

10.1071/cp18004 ◽

2018 ◽

Vol 69 (11) ◽

pp. 1103 ◽

Cited By ~ 6

Author(s):

Audrey Delahunty ◽

James Nuttall ◽

Marc Nicolas ◽

Jason Brand

Keyword(s):

Climate Change ◽

Carbon Dioxide ◽

High Temperature ◽

Soil Water ◽

Elevated Co2 ◽

Water Availability ◽

Significant Interaction ◽

Heat Waves ◽

Soil Water Availability ◽

Grain Number

Lentil (Lens culinaris Medik.) production in arable, Mediterranean-type climates is limited by heat waves and unreliable rainfall. Under climate change scenarios, increased atmospheric carbon dioxide (CO2) concentration will increase plant growth; however, the net effect of increasing occurrence and intensity of heat waves and drought is unclear. This study tested the response of combined acute high temperature (>32°C) at the early pod-filling stage and (i) crop-available soil water, and (ii) elevated CO2 on three lentil genotypes in two experiments. The three lentil genotypes selected were commercial cultivar PBA Bolt and two landraces sourced from the Australian Grains Genebank, AGG 71457 and AGG 73838. High soil-water availability (0.42 Mg m–3) throughout the growing season increased yield by 28% compared with low soil-water availability (0.35 Mg m–3). Across contrasting water treatments, there was no difference in patterns of crop response to high temperature during the early pod-filling phase (5 days at 42°C daytime, 25°C night), where yields were reduced by 45%. A significant interaction between high temperature response and genotype was observed, where reduction in grain number was higher for AGG 73838 (0.20% per degree-hour >32°C) than for AGG 71457 (0.07% per degree-hour >32°C) or PBA Bolt (0.10% per degree-hour >32°C). For heat and CO2 effects, there was no significant interaction between high temperature (3 days at 38°C daytime, ambient night temperature) and CO2 treatment on yield components. There was, however, an overall trend of increased biomass, grain number and yield due to elevated CO2. Although non-limiting soil water did not reduce the impact of high temperature in this study, the range in response across genotypes to high temperature supports opportunity for increased adaptation of lentil toward increasing yield stability under effects of climate change.

Download Full-text