scholarly journals The Relationship between Diaspore Characteristics with Phylogeny, Life History Traits, and Their Ecological Adaptation of 150 Species from the Cold Desert of Northwest China

2014 ◽  
Vol 2014 ◽  
pp. 1-19 ◽  
Author(s):  
Hui-Liang Liu ◽  
Dao-Yuan Zhang ◽  
Shi-Min Duan ◽  
Xi-Yong Wang ◽  
Ming-Fang Song
Keyword(s):  
Life History ◽  
Life History Traits ◽  
Northwest China ◽  
Biological Characteristics ◽  
Ecological Adaptation ◽  
Gurbantunggut Desert ◽  
Cold Desert ◽  
Dispersal Syndromes ◽  
Gurbantünggüt Desert ◽  
The Relationship

Diaspore characteristics of 22 families, including 102 genera and 150 species (55 represented by seeds and 95 by fruits) from the Gurbantunggut Desert were analyzed for diaspore biological characteristics (mass, shape, color, and appendage type). The diaspore mass and shape were significantly different in phylogeny group (APG) and dispersal syndromes; vegetative periods significantly affected diaspore mass, but not diaspore shape; and ecotypes did not significantly affect diaspore mass and shape, but xerophyte species had larger diaspore mass than mesophyte species. Unique stepwise ANOVA results showed that variance in diaspore mass and shape among these 150 species was largely dependent upon phylogeny and dispersal syndromes. Therefore, it was suggested that phylogeny may constrain diaspore mass, and as dispersal syndromes may be related to phylogeny, they also constrained diaspore mass and shape. Diaspores of 85 species (56.67%) had appendages, including 26 with wings/bracts, 18 with pappus/hair, 14 with hooks/spines, 10 with awns, and 17 with other types of appendages. Different traits (mass, shape, color, appendage, and dispersal syndromes) of diaspore decided plants forming different adapted strategies in the desert. In summary, the diaspore characteristics were closely related with phylogeny, vegetative periods, dispersal syndromes, and ecotype, and these characteristics allowed the plants to adapt to extreme desert environments.

scholarly journals Seed Dispersal and Germination Traits of 70 Plant Species Inhabiting the Gurbantunggut Desert in Northwest China

2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
Huiliang Liu ◽  
Daoyuan Zhang ◽  
Xuejun Yang ◽  
Zhenying Huang ◽  
Shimin Duan ◽  
...  
Keyword(s):  
Seed Dispersal ◽  
Seed Size ◽  
Seed Mass ◽  
Northwest China ◽  
Germination Percentage ◽  
Gurbantunggut Desert ◽  
Seed Shape ◽  
Dispersal Syndromes ◽  
Gurbantünggüt Desert ◽  
Germination Traits

Seed dispersal and germination were examined for 70 species from the cold Gurbantunggut Desert in northwest China. Mean and range (3 orders of magnitude) of seed mass were smaller and narrower than those in other floras (5–8 orders of magnitude), which implies that selection favors relatively smaller seeds in this desert. We identified five dispersal syndromes (anemochory, zoochory, autochory, barochory, and ombrohydrochory), and anemochorous species were most abundant. Seed mass (F=3.50,P=0.01), seed size (F=8.31,P<0.01), and seed shape (F=2.62,P=0.04) differed significantly among the five dispersal syndromes and barochorous species were significantly smaller and rounder than the others. There were no significant correlations between seed mass (seed weight) (P=0.15), seed size (P=0.38), or seed shape (variance) (P=0.95) and germination percentage. However, germination percentages differed significantly among the dispersal syndromes (F=3.64,P=0.01) and seeds of ombrohydrochorous species had higher germination percentages than those of the other species. In the Gurbantunggut Desert, the percentage of species with seed dormancy was about 80%. In general, our studies suggest that adaptive strategies in seed dispersal and germination of plants in this area are closely related to the environment in which they live and that they are influenced by natural selection forces.

Ecological adaptation drives wood frog population divergence in life history traits

Heredity ◽  
2021 ◽  
Author(s):  
Emily H. Le Sage ◽  
Sarah I. Duncan ◽  
Travis Seaborn ◽  
Jennifer Cundiff ◽  
Leslie J. Rissler ◽  
...  
Keyword(s):  
Life History ◽  
Life History Traits ◽  
Ecological Adaptation ◽  
Wood Frog ◽  
Population Divergence

Characteristic on the Stability of Haloxylon Ammodendron Plantation in the Southern Fringe of Gurbantunggut Desert, Northwest China

2021 ◽  
Author(s):  
Qinghong Luo ◽  
Qimin Chen ◽  
Miao He ◽  
Na Li
Keyword(s):  
Northwest China ◽  
Gurbantunggut Desert ◽  
Haloxylon Ammodendron ◽  
Coordinated Development ◽  
Soil System ◽  
Management Measures ◽  
Gurbantünggüt Desert ◽  
The Stability ◽  
Southern Fringe ◽  
System Coupling

Using chronosequence theory and method, the characteristics of vegetation-soil coupling and structure stability of Haloxylon ammodendron plantations in the southern fringe of Gurbantunggut Desert were analyzed. The results showed, the canopy storey of H. ammodendron plantation experienced three stages, rapid growth (the age of 7 to 20), then slow growth (the age of 20 to 28) and last decline (over the age of 28). The best natural regeneration started from 17-yr-old plantation. Vegetation-soil system coupling degree (C) and coupling coordinative degree (D) of plantations with different age were not one-to-one correspondence. The system of H. ammodendron plantations always stayed in disorder recession, vegetation and soil were prone to loss type during the process of sand-fixation. Five principal components evaluated that the first rank was 42-yr-old plantation. It was inferred that the trend of the vegetation and soil system was from senescence to harmonious development. So the trend of coordinated development between vegetation and soil would be promoted, if the artificial tending and management measures strengthened.

scholarly journals Optimal immune specificity at the intersection of host life history and parasite epidemiology

2021 ◽  
Vol 17 (12) ◽  
pp. e1009714
Author(s):  
Alexander E. Downie ◽  
Andreas Mayer ◽  
C. Jessica E. Metcalf ◽  
Andrea L. Graham
Keyword(s):  
Life History ◽  
Life History Traits ◽  
Reproductive Maturity ◽  
Structured Population ◽  
Specificity And Sensitivity ◽  
Population Dynamics Model ◽  
Structured Population Dynamics ◽  
Host Life ◽  
The Relationship ◽  
Shed Light

Hosts diverge widely in how, and how well, they defend themselves against infection and immunopathology. Why are hosts so heterogeneous? Both epidemiology and life history are commonly hypothesized to influence host immune strategy, but the relationship between immune strategy and each factor has commonly been investigated in isolation. Here, we show that interactions between life history and epidemiology are crucial for determining optimal immune specificity and sensitivity. We propose a demographically-structured population dynamics model, in which we explore sensitivity and specificity of immune responses when epidemiological risks vary with age. We find that variation in life history traits associated with both reproduction and longevity alters optimal immune strategies–but the magnitude and sometimes even direction of these effects depends on how epidemiological risks vary across life. An especially compelling example that explains previously-puzzling empirical observations is that depending on whether infection risk declines or rises at reproductive maturity, later reproductive maturity can select for either greater or lower immune specificity, potentially illustrating why studies of lifespan and immune variation across taxa have been inconclusive. Thus, the sign of selection on the life history-immune specificity relationship can be reversed in different epidemiological contexts. Drawing on published life history data from a variety of chordate taxa, we generate testable predictions for this facet of the optimal immune strategy. Our results shed light on the causes of the heterogeneity found in immune defenses both within and among species and the ultimate variability of the relationship between life history and immune specificity.

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