scholarly journals Effect of snowmelt regime on phenology of herbaceous species at and around treeline in Western Himalaya, India

2020 ◽  
Vol 12 (4) ◽  
pp. 901-919
Author(s):  
Bhupendra S. ADHIKARI ◽  
Rahul KUMAR
Keyword(s):  
Western Himalaya ◽  
Common Species ◽  
Seed Maturation ◽  
Herbaceous Plant ◽  
Spring Phenology ◽  
Treeline Ecotone ◽  
Warming Climate ◽  
Phenological Changes ◽  
Early Snowmelt ◽  
Herb Species

The present study attempts to investigate the phenological changes of herbaceous plant species in early snowmelt microsite and late snowmelt microsite in treeline ecotone (3200-3300 m asl) at Tungnath, western Himalaya. Four sites, each with two microsites (early snowmelt: ES and late snowmelt: LS) were selected and within each microsite, 3 quadrats (1x1m each) were permanently laid and studied for phenology. Eighty-six species were recorded, of which the proportion of perennial forbs, hemicryptophytes and natives was 90, 84 and 70%, respectively. The early phenophase was noticed in the majority of species in ES microsite than that of LS microsite and the timing of different phenophases varied among microsites. The vegetative phase peaked July (75.6%), while flowering, fruiting and seed maturation phases peaked in August (72.1% and 23.3%, respectively) and 71% species attained the senescence during September. This indicates that species might adapt to the different adaptation to a warming climate. Immediately after the snowmelt 10 species were observed in flowering, while 11 species were in the bud development phase. Comparing 13 common species of the present study with those of past in same or similar study areas indicates that timing and duration of vegetative and flowering phenophase (77% and 69%, respectively) have advanced and lengthened, while fruiting and seed maturation have shortened. Furthermore, phenophase initiation has advanced for flowering (69% species), fruiting (46% species) and senescence (38% species) phases. It seems that the early snowmelt influences spring phenology of herb species on the microsite level and may continue to influence the overall phenology of species for the whole growing season in timberline.

scholarly journals Links between plant species’ spatial and temporal responses to a warming climate

2014 ◽  
Vol 281 (1779) ◽  
pp. 20133017 ◽  
Author(s):  
Tatsuya Amano ◽  
Robert P. Freckleton ◽  
Simon A. Queenborough ◽  
Simon W. Doxford ◽  
Richard J. Smithers ◽  
...  
Keyword(s):  
Species Distribution Models ◽  
Range Shifts ◽  
Niche Conservatism ◽  
Historical Records ◽  
Perennial Species ◽  
Distribution Models ◽  
Climatic Niche ◽  
Warming Climate ◽  
Phenological Changes

To generate realistic projections of species’ responses to climate change, we need to understand the factors that limit their ability to respond. Although climatic niche conservatism, the maintenance of a species’s climatic niche over time, is a critical assumption in niche-based species distribution models, little is known about how universal it is and how it operates. In particular, few studies have tested the role of climatic niche conservatism via phenological changes in explaining the reported wide variance in the extent of range shifts among species. Using historical records of the phenology and spatial distribution of British plants under a warming climate, we revealed that: (i) perennial species, as well as those with weaker or lagged phenological responses to temperature, experienced a greater increase in temperature during flowering (i.e. failed to maintain climatic niche via phenological changes); (ii) species that failed to maintain climatic niche via phenological changes showed greater northward range shifts; and (iii) there was a complementary relationship between the levels of climatic niche conservatism via phenological changes and range shifts. These results indicate that even species with high climatic niche conservatism might not show range shifts as instead they track warming temperatures during flowering by advancing their phenology.

Understory species interactions in mature boreal mixedwood forests

Botany ◽  
2010 ◽  
Vol 88 (10) ◽  
pp. 912-922 ◽  
Author(s):  
Virginia Chávez ◽  
S. Ellen Macdonald
Keyword(s):  
Environmental Factors ◽  
Species Interactions ◽  
Common Species ◽  
Herbaceous Layer ◽  
Competition Intensity ◽  
Understory Species ◽  
Mixedwood Forests ◽  
Natural Logarithm ◽  
Cornus Canadensis ◽  
Herb Species

We explored interactions among plant growth forms in the understory of mature boreal mixedwood forests in western Canada by investigating the competitive influence of erect shrubs on herbs (forbs and grasses). We established 10 pairs of plots; all erect shrubs were removed in one plot of each pair (removals) and left intact in the other plot (controls). Two years later, we harvested all aboveground biomass of the herbaceous layer (herb biomass: this included graminoids, forbs, trailing shrubs, and species with a woody base but not woody stems) from the 20 plots. We tested for significant differences in understory species biomass and composition between control and removal plots and examined the influence of 25 environmental factors on species composition of the herbaceous layer. Competition intensity was measured by the natural logarithm of response ratio (ln RR) index based on herb biomass. After erect shrub removal, there was a significant increase in herb biomass, mostly due to an increase of the most common species (e.g., Cornus canadensis Linnaeus, Linnaea borealis Linnaeus). The values of competition intensity (ln RR) varied among herb species but were, overall, positive, indicating a release from competition following shrub removal. Composition of the herbaceous layer was significantly different between removal and control plots and was also significantly related to seven environmental factors, which explained 40% of the variation in composition. Our study suggests that there is asymmetric competition for light between erect shrub and herb species in boreal ecosystems.

Experimental removal of a dominant species at two levels of soil fertility

1989 ◽  
Vol 67 (12) ◽  
pp. 3470-3477 ◽  
Author(s):  
Jessica Gurevitch ◽  
Robert S. Unnasch
Keyword(s):  
Species Richness ◽  
Species Diversity ◽  
Soil Fertility ◽  
Dominant Species ◽  
Dactylis Glomerata ◽  
Common Species ◽  
Herbaceous Plant ◽  
Old Field ◽  
Steep Decline ◽  
Dactylis Glomerata L

Fertilization of the soil in herbaceous plant communities has been observed to lead to an increase in productivity but a decline in species richness and diversity. We tested the hypothesis that the decline in diversity is due to increased competition from a dominant species by removing the dominant species, Dactylis glomerata L., from an old field community with and without fertilization. Fertilization without the removal of Dactylis resulted in a steep decline in species numbers and in species diversity. The removal of Dactylis when fertilizer was added prevented the decline in species richness. Removal of this dominant species led to an increase in species diversity, an increase in either the frequency or the abundance of almost half of the common species in the system, and an increase in the combined biomass of uncommon species. The response to the removal of Dactylis was greater at higher than at low soil fertility for most but not all variables. Key words: old-field, fertilization, competition, species diversity, community structure, Dactylis glomerata.

scholarly journals Vascular plants, Kinnaur, Himachal Pradesh, India

Check List ◽  
2012 ◽  
Vol 8 (3) ◽  
pp. 321 ◽  
Author(s):  
Amit Chawla ◽  
Om Parkash ◽  
Varun Sharma ◽  
S. Rajkumar ◽  
Brij Lal ◽  
...  
Keyword(s):  
Plant Communities ◽  
Vascular Plants ◽  
Growth Habit ◽  
Western Himalaya ◽  
Himachal Pradesh ◽  
Baseline Data ◽  
Conservation Areas ◽  
Rich Family ◽  
Quantitative Studies ◽  
Herb Species

In the present study, we provide a checklist of the vascular plants of Kinnaur district situated in the Himachal Pradesh state of India in the western Himalaya. This checklist includes 893 taxa (viz., species, subspecies and varieties) belonging to 881 species of angiosperms and gymnosperms distributed among 102 families and 433 genera, and 30 species of pteridophytes. Information about the growth habit, threat and endemicity status is also provided. Our results show that family Compositae is by far the most species rich family with 122 species, followed by Poaceae (69), Rosaceae (58), Leguminosae (49) and Lamiaceae (38). Among the genera, Artemisia is the most diverse genus with 19 species, followed by Potentilla (14), Saussurea (13), Polygonum (11), Astragalus (10), Lonicera (10) and Nepeta (10). Similar to other regions in the western Himalayan range, family-to-genera ratio was 1:4.25 and the genera-to-species ratio was 1:2.04. Out of 893 taxa, our checklist includes 606 herb species, 63 trees, 108 shrubs, 28 climbers, 67 graminoids and 21 sedges and rushes. Of all the species recorded, 108 (12.2%) are endemic to western Himalaya and 27 (3%) are placed under IUCN threatened categories. The present checklist on the flora of Kinnaur provides an important baseline data for further quantitative studies on the characteristics of plant communities in this region and will help in the identification of priority conservation areas.

scholarly journals Allocation of the diet of the Argentine Islands’ inshore ichthyofauna

2021 ◽  
Vol 29 (1) ◽  
pp. 67-72
Author(s):  
A. V. Zinkovskyi ◽  
I. V. Dykyy ◽  
V. M. Trokhymets
Keyword(s):  
Dominant Species ◽  
Common Species ◽  
Ecosystem Change ◽  
Hepatosomatic Index ◽  
Fish Diets ◽  
Phenological Changes ◽  
Pagothenia Borchgrevinki ◽  
Notothenia Coriiceps ◽  
Trematomus Bernacchii ◽  
Access To Food

Fish diets are important indicators of ecosystem change. This aspect of the ichthyofauna of the coast of the Argentine Islands has been insufficiently studied in comparison with other regions. This article presents the results of comparison of dietary and somatic parameters of the dominant species Notothenia coriiceps depending on the point, depth and season of catch. The sample was collected between February 2006 and February 2007. In the year of study, N. coriiceps, Trematomus bernacchii, Chaenocephalus aceratus (common species), Harpagifer antarcticus and Pagothenia borchgrevinki (rare species in this region) were caught. The average fish size in this region does not differ from other places in the Southern Ocean. In Cornice Channel and Stella Creek, N. coriiceps was smaller than at other points due to the narrowness and shallow depth of these places. In winter, large individuals apparently migrated from the coast. The diet of N. coriiceps consisted mainly of crustaceans and seaweeds, with a small number of mollusks (especially limpets), which are common. The number of fish in the diet of N. coriiceps is relatively low for this region. Access to food was relatively the same at different points and depths of the catch. The lowest amount of food was in the fall, the highest amount of food was in the spring and summer. The condition and hepatosomatic index also did not change depending on the point and depth of the catch, but they were low in spring and high in summer. Perhaps this is due to the low energy value of food, which is not compensated by the amount. It is necessary to conduct studies of the diet of N. coriiceps in other years to clarify the specificity of fish in the diet and phenological changes in somatic parameters. Similar studies are needed for other species in the region if catches are sufficient to collect a representative sample.

scholarly journals Composition, richness and floristic diversity along an elevational gradient in a semi-disturbed treeline ecotone, Bhaderwah, Jammu and Kashmir

2019 ◽  
Vol 11 (1) ◽  
pp. 23-34
Author(s):  
Dinesh Singh ◽  
Anu Sharma ◽  
Neeraj Sharma
Keyword(s):  
Plant Species ◽  
Elevational Gradient ◽  
Plant Species Richness ◽  
Tree Line ◽  
Lesser Himalaya ◽  
Jammu And Kashmir ◽  
Treeline Ecotone ◽  
Field Surveys ◽  
Alpine Zone ◽  
Herb Species

The paper deals with plant species richness - diversity relationship along the rising elevation in a semi-disturbed tree line ecotone in upper Bhaderwah, a part of lesser Himalaya. 253 plant species distributed over 170 genera and 62 families were recorded during the intensive field surveys carried during May 2014 to September 2016. These included 11 trees, 29 shrubs and 213 herb species with 247 angiosperms and 6 gymnosperms. Family Asteraceae with 37 species dominated the study area. Maximum richness (179) was observed at sub-alpine zone (Site IV) while the trees (H'=1.74) and shrubs (H'=2.48) revealed maximum diversity at Site III and herbs at Site IV (H'=4.60). The maximum evenness for trees, shrubs and herbs was exhibited by sites III (J'=0.79), V (J'=0.87) and VI (J'=0.94), respectively. The diversity and evenness showed an incremental rise along the rising elevation reaching maxima at the mid elevation with Site-IV being the species rich and Site-VII species deficit, which implies that sub-alpine and alpine forests need effective monitoring and conservation.

scholarly journals Susceptibility of Eight Herbs to Common Root-Knot Nematodes

2002 ◽  
Vol 20 (2) ◽  
pp. 101-103
Author(s):  
Jerry T. Walker
Keyword(s):  
Meloidogyne Incognita ◽  
Mass Production ◽  
Root Systems ◽  
Common Species ◽  
Egg Mass ◽  
Common Root ◽  
Root Knot Nematode ◽  
Root Knot Nematodes ◽  
Gall Index ◽  
Herb Species

Abstract Eight herb species were inoculated with two common species of root-knot nematode and grown for 2 months in a greenhouse. Root systems were examined for galls and egg mass production. All herb species were susceptible but developed fewer galls and had lower gall indices than Rutgers tomato. Burnet, chives, valerian and winter savory had few galls or low gall indices. Eggs were produced on all. Chamomile had a high gall index. Chicory, parsley, and sorrel had intermediate indices. Herbs were equally susceptible to the southern (Meloidogyne incognita) and peanut root-knot nematodes (M. arenaria), particularly at the highest inoculum densities. Mean dry weights of inoculated herbs were not always significantly less than the non-inoculated plants, suggesting that some herbs may be tolerant to root-knot nematodes.

Vegetation dry matter dynamics along treeline ecotone in Western Himalaya, India

2020 ◽  
Vol 61 (1) ◽  
pp. 116-127 ◽  
Author(s):  
Ishwari Datt Rai ◽  
Hitendra Padalia ◽  
Gajendra Singh ◽  
Bhupendra Singh Adhikari ◽  
Gopal Singh Rawat
Keyword(s):  
Dry Matter ◽  
Western Himalaya ◽  
Treeline Ecotone

scholarly journals Effects of temperature variability and extremes on spring phenology across the contiguous United States from 1982 to 2016

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Lingling Liu ◽  
Xiaoyang Zhang
Keyword(s):  
United States ◽  
Interannual Variation ◽  
Vegetation Index ◽  
Climate Modeling ◽  
Terrestrial Ecosystems ◽  
Spring Phenology ◽  
Warming Climate ◽  
Spring Temperatures ◽  
Term Data

Abstract Warming climate and its impact on vegetation phenological trends have been widely investigated. However, interannual variability in temperature is considerably large in recent decades, which is expected to trigger an increasing trend of variation in vegetation phenology. To explore the interannual phenological variation across the contiguous United States (CONUS), we first detected the onset of vegetation greenup using the time series of the daily two-band Enhanced Vegetation Index (EVI2) observed from the AVHRR Long-Term Data Record (1982–1999) and the MODIS Climate Modeling Grid (2000–2016). We then calculated the interannual variation in greenup onset during four decadal periods: 1982–1989, 1990–1999, 2000–2009 and 2010–2016. Further, the trend of interannual variation in greenup onset from 1982 to 2016 was analyzed at pixel and state levels. Extreme phenological events were also determined using a greenup onset anomaly for each pixel. Similar approaches were applied to spring temperatures to detect extreme years and to the temporal trend of interannual variation to explain the phenological variation. The results revealed that 62% of pixels show an increasing interannual variation in greenup onset, and in 44% of pixels, this variation could be explained by the temperature. Although extreme phenology occurred locally in different years, three nationwide extreme phenological years were distinguished. The extreme warm spring that occurred in 2012 resulted in the occurrence of greenup onset as much as 20 days earlier than normal in large parts of the CONUS. In contrast, greenup onset was much later (up to 30 days) in 1983 and 1996 due to cool spring temperatures. These findings suggest that interannual variation in spring phenology could be much stronger in the future in response to climate variation, which could have more significant impacts on terrestrial ecosystems than the regular long-term phenological trend.

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