Influence of water availability in the distributions of branched glycerol dialkyl glycerol tetraether in soils of the Iberian Peninsula

Abstract. The combined application of the MBT (degree of methylation) and CBT (degree of cyclization) indices, based on the distribution of branched glycerol dialkyl glycerol tetraethers (brGDGTs) in soils, has been proposed as a paleoproxy to estimate mean annual temperature (MAT). CBT quantifies the degree of cyclization of brGDGTs and relates to soil pH. MBT and the simplified version MBT' quantify the degree of methylation of brGDGTs and relate to MAT and soil pH. However, other factors such as soil water availability have also been suggested to influence MBT' and possibly restrict the combined application of the MBT' and CBT indices as a paleotemperature proxy. To assess the effect of hydrological conditions on MBT' and CBT, a set of 23 Iberian Peninsula soil samples, covering a MAT range from 10 to 18 °C and a mean annual precipitation (MAP) range of 405 mm to 1455 mm, was analyzed. We found that the CBT was indeed significantly correlated with soil pH in our sample set. In contrast, MBT' was not correlated with MAT but had a significant correlation with the aridity index (AI), a parameter related to water availability in soils. The AI can explain 50% of the variation of the MBT', and 70% of the residuals of MAT estimated with the MBT/CBT proxy as compared to instrumentally measured MAT. We propose that, in arid settings, where water may be an ecologically limiting factor, MBT' is influenced by hydrological conditions rather than temperature. Thus, our results suggest that the combination of MBT' and CBT indices should be applied with caution in paleotemperature reconstructions in soils from dry subhumid to hyperarid environments.

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Water availability determines branched glycerol dialkyl glycerol tetraether distributions in soils of the Iberian Peninsula

Biogeosciences Discussions ◽

10.5194/bgd-10-9043-2013 ◽

2013 ◽

Vol 10 (6) ◽

pp. 9043-9068 ◽

Cited By ~ 2

Author(s):

J. Menges ◽

C. Huguet ◽

J. M. Alcañiz ◽

S. Fietz ◽

D. Sachse ◽

...

Keyword(s):

Iberian Peninsula ◽

Soil Ph ◽

Water Availability ◽

Aridity Index ◽

Mean Annual Precipitation ◽

Mean Annual Temperature ◽

Moisture Regimes ◽

Wide Range ◽

Moisture Conditions ◽

Significant Attention

Abstract. The MBT/CBT has recently gained significant attention as a novel paleotemperature proxy. It is based on the distribution of branched glycerol dialkyl glycerol tetraethers (GDGTs) in soils. The CBT quantifies the degree of cyclisation and relates to soil pH. The MBT' quantifies the degree of methylation and relates to mean annual temperature and soil pH. Combining these two indices allows estimation of mean annual temperature (MAT). However other factors such as soil water availability or moisture conditions have been suggested to influence the MBT'. To assess the effect of moisture conditions on the MBT'/CBT a set of 23 Iberian Peninsula soil samples covering a temperature range from 10–18 °C and a wide range of soil moisture regimes (405 mm to 1455 mm mean annual precipitation per year), was analyzed. We find that CBT is significantly correlated to soil pH confirming it as a robust proxy. In contrast the MBT' index was not correlated to MAT and was weakly correlated to annual mean precipitation (MAP). Instead we found a significant correlation between MBT' and the Aridity Index (AI), a parameter related to water availability in soils. The AI can explain 70% of the residuals of MAT estimation and 50% of the actual variation of the MBT'. This suggests that in dry environments or under moisture shortage the degree of methylation of branched GDGTs is not controlled by temperature but rather by the degree of water available. Our results suggest that the MBT/CBT index is not applicable as a paleotemperature proxy in dry subhumid to hyperarid environments.

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High Resolution of Water Availability for Emilia-Romagna Region over 1961–2015

Advances in Meteorology ◽

10.1155/2018/2489758 ◽

2018 ◽

Vol 2018 ◽

pp. 1-13 ◽

Cited By ~ 4

Author(s):

F. Cervi ◽

M. M. Nistor

Keyword(s):

Water Availability ◽

Soil Surface ◽

Mean Annual Precipitation ◽

Mean Annual Temperature ◽

North East ◽

The North ◽

Precipitation Decrease ◽

Normal Period ◽

Emilia Romagna Region ◽

Annual Water

In this study, monthly time series of precipitations and temperatures from 1024 controlled and homogeneous meteorological stations located in the Emilia-Romagna region (northern Italy) are processed in order to assess potential climate changes that occurred during the period 1961–2015. Normal period as baseline between 1961 and 1990 (1990s) and recent period between 1991 and 2015 (2010s) were adopted in this study to analyse the possible effect of climate change on water availability during long-term period. Based on monthly and annual temperature (TT), precipitation (PP), and potential (ET0), the actual evapotranspiration (AET0) and water availability (WA) were computed at high spatial resolution. Between the two analysed periods, during the 2010s, it was found an increase in the maximum mean annual temperature by 1.08°C while the maximum mean annual precipitation saw a slight decrease (from 2222 mm to 2086 mm). The precipitation decrease is more intense in the South and West sectors of area (8%) and mainly depends on negative changes taking place during the winter and the beginning of spring (from December to March). The maximum mean annual ET0 and AET0 reached values of 663 mm and 565 mm during the 1990s, while during the 2010s, the found values were 668 mm and 572 mm, respectively. Because of the decrease in precipitation and increase in the ET0 and AET0, the WA (the proportion of precipitation that is available at the soil surface for subsequent infiltration and runoff processes) shows a reduction (about 10–20%) in the whole region, with exception of the North-East part of the Emilia-Romagna region. The decrease in the mean annual water availability induces severe issues concerning the water resources management across the whole Emilia-Romagna region.

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Plant phenology in relation to water availability: herbaceous and woody species in the savannas of northern Cameroon

Journal of Tropical Ecology ◽

10.1017/s0266467400008713 ◽

1995 ◽

Vol 11 (2) ◽

pp. 237-254 ◽

Cited By ~ 68

Author(s):

J. Seghieri ◽

Ch. Floret ◽

R. Pontanier

Keyword(s):

Water Resources ◽

Water Availability ◽

Woody Plants ◽

Woody Species ◽

Mean Annual Precipitation ◽

Limiting Factor ◽

Northern Cameroon ◽

Soil Substrates ◽

Herbaceous And Woody Plants ◽

Phenological Phases

ABSTRACTPhenological patterns of herbaceous and woody plants well represented in the Sudano-Sahelian savannas of northern Cameroon were studied in relation to water availability in three contrasted soil types. Mean annual precipitation in this region is 800 mm, entirely restricted to the period May-June to September-October, but redistribution of rainwater by varying soil substrates leads to considerable heterogeneity in available water resources for plants. Results are discussed in terms of probable competition for water resources among co-occurring plants and the adaptations shown by observed patterns to prevailing environmental conditions. Water stress is seen to be a limiting factor to plant growth but does not constitute the sole trigger for the phenological phases observed, nor is it the principal factor responsible for the preponderance of annual species in the herbaceous stratum.

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Effects of environmental factors on weed species composition of cereal and stubble fields in western Hungary

Open Life Sciences ◽

10.2478/s11535-009-0079-0 ◽

2010 ◽

Vol 5 (2) ◽

pp. 283-292 ◽

Cited By ~ 10

Author(s):

Gyula Pinke ◽

Robert Pál ◽

Zoltán Botta-Dukát

Keyword(s):

Environmental Factors ◽

Species Composition ◽

Soil Ph ◽

Vegetation Period ◽

Mean Annual Precipitation ◽

Mean Annual Temperature ◽

Weed Species ◽

Factors Affecting ◽

Weed Communities ◽

Winter Annuals

AbstractMultivariate analysis of data obtained from 184 cereal and stubble fields in low-input agricultural systems located in western Hungary was undertaken in order to asses environmental factors affecting weed species composition. For each variable, the gross and net effect on weed species composition was calculated. All variables considered in this study had a significant effect on weed species composition and explained 26.99% of the total variation. Most variation in species composition was explained by the aspect (cereal vs. stubble), followed by soil pH, mean annual precipitation, soil texture, mean annual temperature, and altitude. Separating the cereals and stubbles soil pH became the most important factor. Our results suggest that during the long vegetation period, cereal weed communities dominated by winter annuals are replaced by stubble-field weed communities dominated by summer annuals. This seasonal change may also have the same important effect on weed species composition as crop types.

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SPLINE MODELS OF CONTEMPORARY, 2030, 2060 AND 2090 CLIMATES FOR MICHOACÁN STATE, MÉXICO. IMPACTS ON THE VEGETATION

Revista Fitotecnia Mexicana ◽

10.35196/rfm.2012.4.333 ◽

2012 ◽

Vol 35 (4) ◽

pp. 333

Author(s):

Cuauhtémoc Sáenz-Romero ◽

Gerald E. Rehfeldt ◽

Nicholas L. Crookston ◽

Pierre Duval ◽

Jean Beaulieu

Keyword(s):

General Circulation ◽

Climate Models ◽

Climate Model ◽

Aridity Index ◽

General Circulation Models ◽

Annual Precipitation ◽

Mean Annual Precipitation ◽

Mean Annual Temperature ◽

Emission Scenarios ◽

Weather Stations

Climate data from 149 weather stations of Michoacán State, at Western México, were extracted from a spline climate model developed for México’s contemporary climate (1961-1990), and for climate projected for the decades centered in years 2030, 2060 and 2090. The model was constructed using outputs from three general circulation models (GCMs: Canadian, Hadley and Geophysical Fluid Dynamics) from two emission scenarios (A “pessimistic” and B “optimistic”). Mean annual temperature (MAT), mean annual precipitation (MAP), annual degree days > 5 °C (DD5), and annual aridity index (DD50.5/MAP) were mapped for Michoacán at an 1 km2 scale, and means were estimated averaging all weather stations. The state average in GCMs and emission scenarios point out that mean annual temperature would increase 1.4 °C by year 2030, 2.2 °C by year 2060 and 3.6 °C by year 2090; whereas annual precipitation would decrease 5.6 % by year 2030, 5.9 % by year 2060 and 7.8 % by year 2090. Climate models can be used for inferring plant-climate relationships and for developing programs to counteract global warming effects. Climate variables were estimated also at Pinus hartwegii and Pinus pseudostrobus growth locations, at Pico de Tancítaro in Central Western Michoacán and Nuevo San Juan Parangaricutiro (near Tancítaro), respectively. According to the annual aridity index values estimated for such locations, it is necessary to conduct assisted migration to match current genotypes to projected climates. This translates into an altitudinal shift of 400 to 450 m higher to match 2030 climates predicted by Canadian Model scenario A2, and 600 to 800 m to match 2060 climates.

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Lupinus elegans KUNTH ASSISTED MIGRATION IN COMMON GARDEN FIELD TESTS

Revista Fitotecnia Mexicana ◽

10.35196/rfm.2014.2.107 ◽

2014 ◽

Vol 37 (2) ◽

pp. 107

Author(s):

José C. Soto-Correa ◽

Roberto Lindig-Cisneros ◽

Cuauhtémoc Sáenz-Romero

Keyword(s):

Plant Height ◽

Field Tests ◽

Aridity Index ◽

Common Garden ◽

Field Trials ◽

Mean Annual Precipitation ◽

Mean Annual Temperature ◽

Assisted Migration ◽

Lower Altitude ◽

Place Of Origin

Lupinus elegans is a species used in ecological restoration and agroforestry programs, because it is tolerant to stress and fixes nitrogen. Genetic variation in quantitative traits was studied in six populations of L. elegans collected along an altitudinal gradient (2312 to 2885 m) in the Mil Cumbres region, east-central Michoacán state, México. Provenance tests were planted at 2600 and 2800 m altitude in two common garden field trials. Tests aimed to evaluate the performance at a different altitude than the site of the seed source, simulating an altitudinal-assisted migration. Survival, plant height growth and aerial biomass were measured. For each provenance and experimental sites, climatic variables were estimated for contemporary climate (average 1961-1990) and future climate (decade centered in 2030, by averaging six model scenarios). It was estimated that by the year 2030 there will be, on average, an increment of 1.4 °C in mean annual temperature, an increase of 518 degree-days > 5 °C (DD5), a 90 mm decrease in mean annual precipitation (MAP) (-7.3 % of contemporary MAP), and a 0.0077 increase in an aridity index (DD50.5/MAP). An ANOVA for each site revealed that in the higher altitude site (2800 m) populations exhibited a pronounced pattern of genetic differentiation (P = 0.0001), in which plant height and biomass are associated with the transfer distance between their place of origin and the experimental site. This distance can be expressed in difference in altitude, mean annual temperature, or aridity index. At the site at higher altitude, plants originated from populations growing at higher altitudes were taller and had more biomass than those originated grown at lower altitudes (R2 ≥ 0.85, P ≤ 0.0302). In contrast, in the lower altitude site (2600 m), although there were nearly significant differences (P ≤ 0.0615) between populations for all of the variables, there was no clinal pattern. In general, the populations grew less when they were moved away from their original climate: those from the higher altitudes grew less in the 2600 m site, and those from the lower altitudes grew less in the 2800 m site. This indicates that climate change will likely induce less growth in several populations, thus it is recommended to promote gradual assisted migration.

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Biological and extrinsic correlates of extinction risk in Chinese lizards

Current Zoology ◽

10.1093/cz/zoab040 ◽

2021 ◽

Author(s):

Yuxi Zhong ◽

Chuanwu Chen ◽

Yanping Wang

Keyword(s):

Body Size ◽

Extinction Risk ◽

Species Traits ◽

Geographic Range ◽

Range Size ◽

Habitat Specialization ◽

Mean Annual Precipitation ◽

Mean Annual Temperature ◽

Small Range ◽

Extrinsic Factors

Abstract China is a country with one of the most species rich reptile faunas in the world. However, nearly a quarter of Chinese lizard species assessed by the China Biodiversity Red List are threatened. Nevertheless, to date, no study has explicitly examined the pattern and processes of extinction and threat in Chinese lizards. In this study, we conducted the first comparative phylogenetic analysis of extinction risk in Chinese lizards. We addressed the following three questions: 1) What is the pattern of extinction and threat in Chinese lizards? 2) Which species traits and extrinsic factors are related to their extinction risk? 3) How can we protect Chinese lizards based on our results? We collected data on ten species traits (body size, clutch size, geographic range size, activity time, reproductive mode, habitat specialization, habitat use, leg development, maximum elevation, and elevation range) and seven extrinsic factors (mean annual precipitation, mean annual temperature, mean annual solar insolation, normalized difference vegetation index (NDVI), human footprint, human population density, and human exploitation). After phylogenetic correction, these variables were used separately and in combination to assess their associations with extinction risk. We found that Chinese lizards with small geographic range, large body size, high habitat specialization, and living in high precipitation areas were vulnerable to extinction. Conservation priority should thus be given to species with the above extinction-prone traits so as to effectively protect Chinese lizards. Preventing future habitat destruction should also be a primary focus of management efforts because species with small range size and high habitat specialization are particularly vulnerable to habitat loss.

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Habitat features of settlement areas used by floaters of Bonelli’s and Golden Eagles

Bird Conservation International ◽

10.1017/s0959270910000213 ◽

2010 ◽

Vol 21 (1) ◽

pp. 59-71 ◽

Cited By ~ 10

Author(s):

JESÚS CARO ◽

DIEGO ONTIVEROS ◽

MANUEL PIZARRO ◽

JUAN M. PLEGUEZUELOS

Keyword(s):

Iberian Peninsula ◽

Habitat Heterogeneity ◽

Habitat Characteristics ◽

Mean Annual Temperature ◽

Habitat Features ◽

Ecological Requirements ◽

Bonelli’S Eagle ◽

Declining Species ◽

Dispersal Period ◽

Settlement Areas

SummaryBonelli’s Eagle Hieraaetus fasciatus and Golden Eagle Aquila chrysaetos are two declining species, in which floaters tend to be located outside of breeding territories during the dispersal period, in so-called settlement areas. We studied settlement areas for both these long-lived raptors in the southern Iberian Peninsula, to gain a better understanding of the ecological requirements of the eagles during their long pre-adult stage, a period accounting for around 80% of the species’ mortality. Eagle abundance was calculated by road censuses, and habitat characteristics of settlement and non-settlement areas compared by General Discriminant Analysis (GDA) and Logistic Regression (LR). The best model of GDA and LR incorporated the abundance of main prey for eagles (rabbits, partridges) and orchard surface area, and explained 100% of eagle presence; the best model selected by GDA also included habitat heterogeneity. Both eagles tended to share settlement areas in the southern Iberian Peninsula and, when they did not, the mean annual temperature and slope appeared to explain the segregation between the two species. Management measures for the conservation of both threatened species during the dispersal period should be focused on identifying settlement areas, maintaining high prey densities and maximum habitat heterogeneity.

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Long-Term Projections of the Natural Expansion of the Pine Wood Nematode in the Iberian Peninsula

Forests ◽

10.3390/f12070849 ◽

2021 ◽

Vol 12 (7) ◽

pp. 849

Author(s):

Begoña de la Fuente ◽

Santiago Saura

Keyword(s):

Iberian Peninsula ◽

Tree Species ◽

Average Rate ◽

Limiting Factor ◽

Pine Wood Nematode ◽

Individual Tree ◽

Pine Wood ◽

Pine Tree ◽

Informative Content

The invasive pine wood nematode (PWN), Bursaphelenchus xylophilus, causal agent of pine wilt disease, was first reported in Europe, near Lisbon, in 1999, and has since then spread to most of Portugal. We here modelled the spatiotemporal patterns of future PNW natural spread in the Iberian Peninsula, as dispersed by the vector beetle Monochamus galloprovincialis, using a process-based and previously validated network model. We improved the accuracy, informative content, forecasted period and spatial drivers considered in previous modelling efforts for the PWN in Southern Europe. We considered the distribution and different susceptibility to the PWN of individual pine tree species and the effect of climate change projections on environmental suitability for PWN spread, as we modelled the PWN expansion dynamics over the long term (>100 years). We found that, in the absence of effective containment measures, the PWN will spread naturally to the entire Iberian Peninsula, including the Pyrenees, where it would find a gateway for spread into France. The PWN spread will be relatively gradual, with an average rate of 0.83% of the total current Iberian pine forest area infected yearly. Climate was not found to be an important limiting factor for long-term PWN spread, because (i) there is ample availability of alternative pathways for PWN dispersal through areas that are already suitable for the PWN in the current climatic conditions; and (ii) future temperatures will make most of the Iberian Peninsula suitable for the PWN before the end of this century. Unlike climate, the susceptibility of different pine tree species to the PWN was a strong determinant of PWN expansion through Spain. This finding highlights the importance of accounting for individual tree species data and of additional research on species-specific susceptibility for more accurate modelling of PWN spread and guidance of related containment efforts.

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Spatial Patterns and Drivers of Soil Chemical Properties in a Typical Hickory Plantation

10.21203/rs.3.rs-845777/v1 ◽

2021 ◽

Author(s):

Mengjiao Sun ◽

Enqing Hou ◽

Jiasen Wu ◽

Jianqin Huang ◽

Xingzhao Huang

Keyword(s):

Random Forest ◽

Soil Nutrients ◽

Spatial Patterns ◽

Abiotic Factors ◽

Soil Nutrient ◽

Parent Material ◽

Mean Annual Precipitation ◽

Nutrient Concentrations ◽

Available Phosphorus ◽

Mean Annual Temperature

Abstract Background: Soil nutrients play critical roles in regulating and improving the sustainable development of economic forests. Consequently, an elucidation of the spatial patterns and drivers of soil nutrients in these forests is fundamental to their management. For this study, we collected 314 composite soils at a 0-30 cm depth from a typical hickory plantation in Lin 'an, Zhejiang Province, China. We determined the concentrations of macronutrients (i.e., soil organic carbon, hydrolyzed nitrogen, available phosphorus, and available potassium) and micronutrients (i.e., iron, manganese, zinc, and copper.) of the soils. We employed random forest analysis to quantify the relative importance of soil-forming factors to predict the soil nutrient concentrations, which could then be extrapolated to the entire hickory region. Results: Random forest models explained 61%–88% of the variations in soil nutrient concentrations. The mean annual temperature and mean annual precipitation were the most important predictor of soil macronutrient and micronutrient concentrations. Moreover, parent material was another key predictor of soil available phosphorus and micronutrient concentrations. Mapping results demonstrated the importance of climate in controlling the spatial distribution of soil nutrient concentrations at finer scales, as well as the effect of parent material, topography, stand structure, and management measures of hickory plantations. Conclusions: Our study highlights the biotic factors, abiotic factors, and management factors control over soil macronutrient and micronutrient concentrations, which have significant implications for the sustainability of soil nutrients in forest plantations.

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