Elevation Gradient Altered Soil C, N, and P Stoichiometry of Pinus taiwanensis Forest on Daiyun Mountain

Researches focused on soil carbon (C), nitrogen (N), and phosphorus (P) content and the stoichiometry characteristics along elevation gradients are important for effective management of forest ecosystems. Taking the soil of different elevations from 900 to 1700 m on Daiyun Mountain as the object, the elevation distribution of total C, N, and P in soil and their stoichiometry characteristics were studied. Also, the driving factors resulting in the spatial heterogeneity of soil stoichiometry are presented. The results show the following: (1) The average soil C and N content was 53.03 g·kg−1 and 3.82 g·kg−1, respectively. The content of C and N at high elevation was higher than that of at low elevation. Soil phosphorus fluctuated with elevation. (2) With increasing elevation, soil C:N ratio increased initially to 17.40 at elevation between 900–1000 m, and then decreased to 12.02 at elevation 1600 m. The changing trends of C:P and N:P were similar, and they all fluctuated with elevation. (3) Elevation, soil bulk density, and soil temperature were the main factors influencing the variation of soil C, N, and C:N. Soil pH and slope position were the driving factors for soil P, C:P, and N:P. The soil is rich in C and N, and has less total phosphorus on Daiyun Mountain. Raising the level of phosphate fertilizer appropriately can help to improve soil fertility and promote plant growth as well. In light of this information, in the near future, it will be necessary to conduct separation management of C, N, and P with regular monitoring systems to maintain favorable conditions for soil.

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Shoot-soil ecological stoichiometry of alfalfa under nitrogen and phosphorus fertilization in the Loess Plateau

Scientific Reports ◽

10.1038/s41598-021-94472-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jiaoyun Lu ◽

Hong Tian ◽

Heshan Zhang ◽

Junbo Xiong ◽

Huimin Yang ◽

...

Keyword(s):

Loess Plateau ◽

Ecological Stoichiometry ◽

Effective Means ◽

Phosphorus Fertilization ◽

The Loess Plateau ◽

Nitrogen And Phosphorus ◽

Soil C ◽

Soil P ◽

P Limitation ◽

C And N

AbstractPlants and soil interactions greatly affect ecosystems processes and properties. Ecological stoichiometry is an effective means to explore the C, N, P correlation between plants and soil and the relationship between plant growth and nutrient supply. Serious soil erosion on China’s Loess Plateau has further barrenness the soil. Fertilization solves the problem of ecosystem degradation by improving soil fertility and regulating the ecological stoichiometric between soil and plants. No fertilization (CK), nitrogen fertilization (N), phosphorus fertilization (P) and N and P combined fertilization (NP) treatments were set in an alfalfa grassland. Organic carbon (C), nitrogen (N) and phosphorus (P) nutrients and their stoichiometry were measured in shoot and soil. P and NP fertilization increased shoot C concentration (3.12%, 0.91%), and all fertilization decreased shoot N concentration (6.96%). The variation of shoot C and N concentrations resulted in a greater increase in shoot C:N under the fertilization treatment than that under CK (8.24%). Most fertilization treatments increased shoot P concentration (4.63%) at each cut, which induced a decrease of shoot C:P. Shoot N:P of most treatments were greater than 23, but it was lower under N and NP fertilization than that under CK. Fertilization only increased soil C in 2014, but had no effect on soil N. Soil P content was significantly higher under P fertilization in 2014 (34.53%), and all fertilization in the second cut of 2015 (124.32%). Shoot and soil C:P and N:P having the opposite changes to shoot and soil P, respectively. Our results suggest that the change of P after fertilization largely drove the changes of stoichiometric. The growth of alfalfa in the Loess Plateau was severely restricted by P. It is an effective method to increase the biomass of alfalfa by increasing the addition of N or NP fertilizer to alleviate P limitation.

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Patterns of floral allocation along an elevation gradient: variation in Senecio subalpinus growing in the Tatra Mountains

Alpine Botany ◽

10.1007/s00035-021-00247-w ◽

2021 ◽

Vol 131 (1) ◽

pp. 117-124

Author(s):

Piotr Kiełtyk

Keyword(s):

Elevation Gradient ◽

High Elevation ◽

Tatra Mountains ◽

Ecological Gradient ◽

Elevation Gradients ◽

Allocation Patterns ◽

Abiotic And Biotic Factors ◽

Elevational Shift ◽

The Tatra Mountains ◽

Gradient Variation

AbstractThis study examined the morphological variation in Senecio subalpinus W.D.J. Koch. (Asteraceae) along a 950-m elevation gradient in the Tatra Mountains, Central Europe, with emphasis on floral allocation patterns. Fifteen morphological traits were measured in 200 plants collected in the field from 20 sites then the findings were modelled by elevation using linear mixed-effects models. Plant aboveground biomass and height decreased steadily with increasing elevation; however, the most distinctive feature was the elevational shift in floral allocation patterns. Low-elevation plants had greater numbers of smaller flower heads with a lower overall number of flowers, while high-elevation plants had smaller numbers of bigger flower heads and a greater overall number of flowers. Accordingly, the mean individual flower mass increased significantly with increasing elevation. Interestingly, the width of the outer ligulate flowers also increased considerably with increasing elevation, increasing the fill of the overall circumference of the flower head. Results of this study confirmed that elevation is an important ecological gradient driving variation in vegetative and floral traits of S. subalpinus. Possible causes of the observed variations are subsequently discussed, including the varying effects of both abiotic and biotic factors with elevation gradients.

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Characteristics of Soil C, N, and P Stoichiometry as Affected by Land Use and Slope Position in the Three Gorges Reservoir Area, Southwest China

Sustainability ◽

10.3390/su13179845 ◽

2021 ◽

Vol 13 (17) ◽

pp. 9845

Author(s):

Mengdie Feng ◽

Dengyu Zhang ◽

Binghui He ◽

Ke Liang ◽

Peidong Xi ◽

...

Keyword(s):

Land Use ◽

Secondary Forest ◽

Slope Position ◽

Three Gorges Reservoir Area ◽

Soil C ◽

Soil P ◽

N:P Ratios ◽

P Concentration ◽

Effects Of Land Use ◽

Lower Slope

Land use change and slope position are commonly identified as the key factors affecting the soil organic carbon (C), total nitrogen (N), and total phosphorus (P) traits in distinct ecological scales. However, the directions of these effects are still unclear in some fragile terrestrial ecosystems. This study aimed to determine the characteristics of soil C, N, and P concentrations and stoichiometry as affected by different land uses and slope positions in a representative purple soil hillslope in Three Gorges Reservoir Area (TGRA), China, which is experiencing severe soil erosion and non-point source pollution. A total of 108 soil samples were collected from secondary forest, orchard plantation, and cropland on the upper, middle, and lower slopes, respectively. Soil C, N, and P concentrations and their stoichiometric ratios were determined. The results showed that soil C concentration was not affected by land use, while soil N and P concentrations were both the highest in orchard plantation rather than in secondary forest and cropland, resulting in the lowest C:N, C:P, and N:P ratios in the orchard plantation. Soil C and N concentrations synchronously decreased from upper slope to the lower slope, and soil P concentration was not markedly different among slope positions. This also caused the insignificant difference in soil C:N ratio and the remarkably lowest C:P and N:P ratios on the lower slope. There were significant interactive effects of land use and slope position on the study soil variables except soil P concentration. Our results highlight the effects of land use and slope position on soil C, N, and P traits and point to the decoupling of linkages between soil P and soil C as well as N due to the severe soil erosion and overuse of fertilization in the TGRA.

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Turnover of Lecanoroid Mycobionts and Their Trebouxia Photobionts Along an Elevation Gradient in Bolivia Highlights the Role of Environment in Structuring the Lichen Symbiosis

Frontiers in Microbiology ◽

10.3389/fmicb.2021.774839 ◽

2021 ◽

Vol 12 ◽

Author(s):

Ian D. Medeiros ◽

Edyta Mazur ◽

Jolanta Miadlikowska ◽

Adam Flakus ◽

Pamela Rodriguez-Flakus ◽

...

Keyword(s):

Dna Sequences ◽

Species Turnover ◽

Elevation Gradient ◽

Single Species ◽

High Elevation ◽

Regional Patterns ◽

Elevation Gradients ◽

Clade C ◽

Community Shifts ◽

Molecular Dataset

Shifts in climate along elevation gradients structure mycobiont–photobiont associations in lichens. We obtained mycobiont (lecanoroid Lecanoraceae) and photobiont (Trebouxia alga) DNA sequences from 89 lichen thalli collected in Bolivia from a ca. 4,700 m elevation gradient encompassing diverse natural communities and environmental conditions. The molecular dataset included six mycobiont loci (ITS, nrLSU, mtSSU, RPB1, RPB2, and MCM7) and two photobiont loci (ITS, rbcL); we designed new primers to amplify Lecanoraceae RPB1 and RPB2 with a nested PCR approach. Mycobionts belonged to Lecanora s.lat., Bryonora, Myriolecis, Protoparmeliopsis, the “Lecanora” polytropa group, and the “L.” saligna group. All of these clades except for Lecanora s.lat. occurred only at high elevation. No single species of Lecanoraceae was present along the entire elevation gradient, and individual clades were restricted to a subset of the gradient. Most Lecanoraceae samples represent species which have not previously been sequenced. Trebouxia clade C, which has not previously been recorded in association with species of Lecanoraceae, predominates at low- to mid-elevation sites. Photobionts from Trebouxia clade I occur at the upper extent of mid-elevation forest and at some open, high-elevation sites, while Trebouxia clades A and S dominate open habitats at high elevation. We did not find Trebouxia clade D. Several putative new species were found in Trebouxia clades A, C, and I. These included one putative species in clade A associated with Myriolecis species growing on limestone at high elevation and a novel lineage sister to the rest of clade C associated with Lecanora on bark in low-elevation grassland. Three different kinds of photobiont switching were observed, with certain mycobiont species associating with Trebouxia from different major clades, species within a major clade, or haplotypes within a species. Lecanoraceae mycobionts and Trebouxia photobionts exhibit species turnover along the elevation gradient, but with each partner having a different elevation threshold at which the community shifts completely. A phylogenetically defined sampling of a single diverse family of lichen-forming fungi may be sufficient to document regional patterns of Trebouxia diversity and distribution.

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Changes in Soil C, N, and P Concentrations and Stoichiometry in Karst Trough Valley Area under Ecological Restoration: The Role of Slope Aspect, Land Use, and Soil Depth

Forests ◽

10.3390/f12020144 ◽

2021 ◽

Vol 12 (2) ◽

pp. 144

Author(s):

Tianyang Li ◽

Jiangmin Zeng ◽

Binghui He ◽

Zhanpeng Chen

Keyword(s):

Land Use ◽

Ecological Restoration ◽

Soil Depth ◽

Interactive Effects ◽

Slope Aspect ◽

Soil C ◽

Soil P ◽

Soil C And N ◽

C And N ◽

Valley Area

This study aims to investigate the roles of slope aspect, land use and soil depth in altering the soil organic carbon (C), total nitrogen (N), and total phosphorus (P) traits in the karst trough valley area experiencing extensive ecological restoration. A total of 54 soil samples were collected at 0–10, 10–20, and 20–30 cm soil depths from secondary forest, plantation forest, and grassland on the relatively more shaded east-facing slope and the contrasting west-facing slope, respectively. The independent and interactive effects of slope aspect, land use, and soil depth on soil C, N, and P concentrations and stoichiometry were determined. The results show that soil C and N concentrations were markedly higher on the east-facing slope than on the west-facing slope, and soil P concentrations showed an opposite trend, leading to significant differences in soil C:P and N:P but not in C:N ratios between the two aspects. Soil C and N concentrations were not affected by land use, and soil P concentration was significantly higher in plantation forest than in secondary forest and grassland. Soil C and N concentrations significantly decreased with increasing soil depth, but soil P concentration presented no significant changes with soil depth. Both the land use and soil depth did not differ in terms of their elemental stoichiometry. There were no significant interactive effects of slope aspect, land use and soil depth on soil C, N, and P traits. Our results indicate that soil C, N, and P changes are more sensitive to slope aspect rather than land use and soil depth in the karst trough valley area under ecological restoration.

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Variation in ant-mediated seed dispersal along elevation gradients

10.7287/peerj.preprints.26783 ◽

2018 ◽

Author(s):

Israel Del Toro ◽

Relena R Ribbons

Keyword(s):

Seed Dispersal ◽

Elevation Gradient ◽

High Elevation ◽

Seed Removal ◽

Species Identity ◽

Insect Communities ◽

Removal Rates ◽

Elevation Gradients ◽

Ant Community ◽

Lower Elevation

Ant-mediated seed dispersal, also known as myrmecochory, is a widespread and important mutualism that structures both plant and insect communities. However the extent to which myrmecochory is driven by abiotic and biotic environmental factors remains unclear. We used a replicated standardized seed removal experiment along elevation gradients in four mountain ranges in the southwestern United States to test predictions that: (1) seed removal rates would be greater at lower elevations, and (2) seed species identity influences seed removal rates, (i.e. seeds from their native elevation range would be removed at higher rates than seeds outside of their range). Both predictions were supported. Seed removal rates were ~25% higher at lower elevation sites than at higher elevation sites. The low elevation Datura and high elevation Iris were removed at higher rates in their respective native ranges. We attribute observed differences in dispersal rates to changes in ant community composition, functional diversity, and abundance, suggesting that temperature variation along the elevation gradient.

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Differential phenotypic and genetic expression of defence compounds in a plant–herbivore interaction along elevation

Royal Society Open Science ◽

10.1098/rsos.160226 ◽

2016 ◽

Vol 3 (9) ◽

pp. 160226 ◽

Cited By ~ 5

Author(s):

Ana L. Salgado ◽

Tomasz Suchan ◽

Loïc Pellissier ◽

Sergio Rasmann ◽

Anne-Lyse Ducrest ◽

...

Keyword(s):

Gene Expression ◽

Host Plant ◽

De Novo ◽

Alternative Hypothesis ◽

Elevation Gradient ◽

High Elevation ◽

Elevation Gradients ◽

Tissue Replacement ◽

Plant Herbivore ◽

Optimal Defence

Elevation gradients impose large differences in abiotic and biotic conditions over short distances, in turn, likely driving differences in gene expression more than would genetic variation per se , as natural selection and drift are less likely to fix alleles at such a narrow spatial scale. As elevation increases, the pressure exerted on plants by herbivores and on arthropod herbivores by predators decreases, and organisms spanning the elevation gradient are thus expected to show lower levels of defence at high elevation. The alternative hypothesis, based on the optimal defence theory, is that defence allocation should be higher in low-resource habitats such as those at high elevation, due to higher costs associated with tissue replacement. In this study, we analyse variation with elevation in (i) defence compound content in the plant Lotus corniculatus and (ii) gene expression associated with defence against predators in the specific phytophagous moth, Zygaena filipendulae . Both species produce cyanogenic glycosides (CNglcs) such as lotaustralin and linamarin as defence mechanisms, with the moth, in addition, being able to sequester CNglcs from its host plant. Specifically, we tested the assumption that the defence-associated phenotype in plants and the gene expression in the insect herbivore should covary between low- and high-elevation environments. We found that L. corniculatus accumulated more CNglcs at high elevation, a result in agreement with the optimal defence theory. By contrast, we found that the levels of expression in the defence genes of Z. filipendulae larvae were not related to the CNglc content of their host plant. Overall, expression levels were not correlated with elevation either, with the exception of the UGT33A1 gene, which showed a marginally significant trend towards higher expression at high elevation when using a simple statistical framework. These results suggest that the defence phenotype of plants against herbivores, and subsequent herbivore sequestration machineries and de novo production, are based on a complex network of interactions.

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Abiotic Parameters and Pedogenesis as Controlling Factors for Soil C and N Cycling Along an Elevational Gradient in a Subalpine Larch Forest (NW Italy)

Forests ◽

10.3390/f10080614 ◽

2019 ◽

Vol 10 (8) ◽

pp. 614

Author(s):

Emanuele Pintaldi ◽

Davide Viglietti ◽

Michele Eugenio D’Amico ◽

Andrea Magnani ◽

Michele Freppaz

Keyword(s):

Snow Cover ◽

Abiotic Factors ◽

Elevation Gradient ◽

Climatic Conditions ◽

N Cycling ◽

Soil Freezing ◽

Soil C ◽

C And N ◽

Snow Cover Duration ◽

C And N Cycling

Mountain regions are vulnerable to climate change but information about the climate sensitivity of seasonally snow-covered, subalpine ecosystems is still lacking. We investigated the impact of climatic conditions and pedogenesis on the C and N cycling along an elevation gradient under a Larch forest in the northwest (NW) Italian Alps. The environmental gradient that occurs over short distances makes elevation a good proxy for understanding the response of forest soils and nutrient cycling to different climatic conditions. Subalpine forests are located in a sensitive elevation range—the prospected changes in winter precipitation (i.e., shift of snowfalls to higher altitude, reduction of snow cover duration, etc.) could determine strong effects on soil nitrogen and carbon cycling. The work was performed in the western Italian Alps (Long-Term Ecological Research- LTER site Mont Mars, Fontainemore, Aosta Valley Region). Three sites, characterized by similar bedrock lithology and predominance of Larix decidua Mill., were selected along an elevation gradient (1550–1900 m above sea level-a.s.l.). To investigate the effects on soil properties and soil solution C and N forms of changing abiotic factors (e.g., snow cover duration, number of soil freeze/thaw cycles, intensity and duration of soil freezing, etc.) along the elevation gradient, soil profiles were opened in each site and topsoils and soil solutions were periodically collected from 2015 to 2016. The results indicated that the coldest and highest soil (well-developed Podzol) showed the highest content of extractable C and N forms (N-NH4+, DON, DOC, Cmicr) compared to lower-elevation Cambisols. The soil solution C and N forms (except N-NO3−) did not show significant differences among the sites. Independently from elevation, the duration of soil freezing, soil volumetric water content, and snow cover duration (in order of importance) were the main abiotic factors driving soil C and N forms, revealing how little changes in these parameters could considerably influence C and N cycling under this subalpine forest stand.

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Climate Sensitivity of Tropical Trees Along an Elevation Gradient in Rwanda

Forests ◽

10.3390/f9100647 ◽

2018 ◽

Vol 9 (10) ◽

pp. 647 ◽

Cited By ~ 1

Author(s):

Myriam Mujawamariya ◽

Aloysie Manishimwe ◽

Bonaventure Ntirugulirwa ◽

Etienne Zibera ◽

Daniel Ganszky ◽

...

Keyword(s):

Water Use Efficiency ◽

Water Use ◽

Climate Sensitivity ◽

Elevation Gradient ◽

High Elevation ◽

Dry Season ◽

Nutrient Ratios ◽

Wet Season ◽

Elevation Gradients ◽

Use Efficiency

Elevation gradients offer excellent opportunities to explore the climate sensitivity of vegetation. Here, we investigated elevation patterns of structural, chemical, and physiological traits in tropical tree species along a 1700–2700 m elevation gradient in Rwanda, central Africa. Two early-successional (Polyscias fulva, Macaranga kilimandscharica) and two late-successional (Syzygium guineense, Carapa grandiflora) species that are abundant in the area and present along the entire gradient were investigated. We found that elevation patterns in leaf stomatal conductance (gs), transpiration (E), net photosynthesis (An), and water-use efficiency were highly season-dependent. In the wet season, there was no clear variation in gs or An with elevation, while E was lower at cooler high-elevation sites. In the dry season, gs, An, and E were all lower at drier low elevation sites. The leaf-to-air temperature difference was smallest in P. fulva, which also had the highest gs and E. Water-use efficiency (An/E) increased with elevation in the wet season, but not in the dry season. Leaf nutrient ratios indicated that trees at all sites are mostly P limited and the N:P ratio did not decrease with increasing elevation. Our finding of strongly decreased gas exchange at lower sites in the dry season suggests that both transpiration and primary production would decline in a climate with more pronounced dry periods. Furthermore, we showed that N limitation does not increase with elevation in the forests studied, as otherwise most commonly reported for tropical montane forests.

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Continental scale climate, land-use and geological controls of soil P cycling and relations with soil C and N

10.5194/egusphere-egu2020-10893 ◽

2020 ◽

Author(s):

Wolfgang Wanek ◽

Daniel Wasner ◽

Johann Püspök ◽

Theresa Böckle ◽

Lisa Noll ◽

...

Keyword(s):

Land Use ◽

Land Uses ◽

Soil C ◽

Soil P ◽

P Pools ◽

P Cycling ◽

Physico Chemical ◽

P Mineralization ◽

Soil C And N ◽

C And N

Despite the importance of phosphorus (P) as a nutrient for all life, its availability is highly constrained in terrestrial ecosystems. The availability of P to plants and microbes is regulated by abiotic processes (e.g. P sorption/desorption, precipitation/dissolution) and biological activities (microbial P immobilization/organic P mineralization). Due to the strong geochemical component of the P cycle, it can be expected that soil C, N and P cycling may differ in terms of effects of geology, climate and management. Despite advances in our understanding of physico-chemical controls on P availability, there is still little mechanistic understanding of large scale controls on soil P cycling and its relation to soil C and N cycling, due to a lack of broad scale studies using common methodologies.Here we aimed to investigate soil physicochemical and biological factors that drive soil P cycling and may cause a (de)coupling of C, N and P processes. We therefore sampled mineral topsoils (0-10 cm, n=95) across a continental transect in Europe (Southern Spain to Northern Scandinavia), covering major geological, climatic and land use gradients. The soils derived from different land uses (cropland, grassland, forest/woodland) and bedrock types (silicate, sediment, calcareous). We analyzed a wide range of potentially relevant physico-chemical and biological properties and measured gross rates of soil N and P processes by short term (24 h) incubations of soils with 33P and 15N following isotope pool dilution approaches.(i) Across the whole transect land-use effects on soil P pools and processes exceeded those of geology, reflecting the accumulation of fertilizer P in soils of managed ecosystems. Cropland (and grasslands) had higher values of soil total P and soil inorganic P (Pi), available Pi (Olsen P), and gross Pi mobilization rates by abiotic and biotic processes compared to forests. Soil phosphatase activity did not vary between land-uses. Soils on silicate bedrock had significantly higher total and labile P than calcareous soils.(ii) Climate differentially affected P pools and processes. Soil total P, dissolved organic P, and gross Pi desorption decreased with mean annual temperature (MAT; these properties were not sensitive to mean annual precipitation - MAP), while soil phosphatase activity and gross total Pi mobilization through abiotic and biotic processes increased with MAP but were insensitive to MAT. This clearly points to adverse climatic controls of biotic and abiotic soil P processes.(iii) We found strong interlinkages between soil C, N and P pools (soil organic matter and microbial biomass) and soil enzymes (beta-glucosidase, chitinase, phosphatase) but not in related gross processes (respiration, N and P mineralization). Interestingly the slopes of C-P and N-P relations of pools and enzymes differed systematically between land-uses, indicating that land management causes a partial decoupling of P from C and N cycles, reflecting the P-richness of croplands.

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