Variation of plant diversity components in different scales in relation to grazing and climatic conditions

2015 ◽  
Vol 8 (4) ◽  
pp. 537-545 ◽  
Author(s):  
Reza Erfanzadeh ◽  
Reza Omidipour ◽  
Marzban Faramarzi
2006 ◽  
Vol 362 (1478) ◽  
pp. 253-262 ◽  
Author(s):  
Chengyu Weng ◽  
Henry Hooghiemstra ◽  
Joost F Duivenvoorden

Change in diversity of fossil pollen through time is used as a surrogate for biodiversity history. However, there have been few studies to explore the sensitivity of the measured pollen diversity to vegetation changes and the relationship between pollen diversity and plant diversity. This paper presents results of a study to assess the relationship between pollen diversity and relative abundance of pollen from different altitudinal vegetation belts (subandean forest, Andean forest, subparamo and grassparamo) in three records from the tropical Andes in Colombia. The results indicated that plant diversity in the vegetation declined with altitude and pollen diversity is positively correlated to the abundance of pollen from lower altitude vegetation belts and negatively correlated to that from the grassparamo. These results, therefore, suggest that pollen diversity coarsely reflects the diversity of the surrounding vegetation. Using this interpretation, we were able to predict changes in plant diversity over the past 430 000 years in the Colombian Andes. Results indicated that under warmer climatic conditions, more species-diverse vegetation of low elevation moved upslope to contribute more pollen diversity to the study sites, and under colder conditions, species-poor grassparamo moved downslope and observed pollen diversity was lower. This study concludes that fossil pollen diversity may provide an important proxy to reconstruct the temporal changes in plant diversity.


2018 ◽  
Vol 115 (33) ◽  
pp. 8400-8405 ◽  
Author(s):  
Pablo García-Palacios ◽  
Nicolas Gross ◽  
Juan Gaitán ◽  
Fernando T. Maestre

The insurance hypothesis, stating that biodiversity can increase ecosystem stability, has received wide research and political attention. Recent experiments suggest that climate change can impact how plant diversity influences ecosystem stability, but most evidence of the biodiversity–stability relationship obtained to date comes from local studies performed under a limited set of climatic conditions. Here, we investigate how climate mediates the relationships between plant (taxonomical and functional) diversity and ecosystem stability across the globe. To do so, we coupled 14 years of temporal remote sensing measurements of plant biomass with field surveys of diversity in 123 dryland ecosystems from all continents except Antarctica. Across a wide range of climatic and soil conditions, plant species pools, and locations, we were able to explain 73% of variation in ecosystem stability, measured as the ratio of the temporal mean biomass to the SD. The positive role of plant diversity on ecosystem stability was as important as that of climatic and soil factors. However, we also found a strong climate dependency of the biodiversity–ecosystem stability relationship across our global aridity gradient. Our findings suggest that the diversity of leaf traits may drive ecosystem stability at low aridity levels, whereas species richness may have a greater stabilizing role under the most arid conditions evaluated. Our study highlights that to minimize variations in the temporal delivery of ecosystem services related to plant biomass, functional and taxonomic plant diversity should be particularly promoted under low and high aridity conditions, respectively.


2020 ◽  
Author(s):  
Sebastian Fiedler ◽  
José A.F. Monteiro ◽  
Kristin B. Hulvey ◽  
Rachel J. Standish ◽  
Michael P. Perring ◽  
...  

ABSTRACTEcological restoration increasingly aims at improving ecosystem multifunctionality and making landscapes resilient to future threats, especially in biodiversity hotspots such as Mediterranean-type ecosystems. Successful realisation of such a strategy requires a fundamental mechanistic understanding of the link between ecosystem plant composition, plant traits and related ecosystem functions and services, as well as how climate change affects these relationships. An integrated approach of empirical research and simulation modelling with focus on plant traits can allow this understanding.Based on empirical data from a large-scale restoration project in a Mediterranean-type climate in Western Australia, we developed and validated the spatially explicit simulation model ModEST, which calculates coupled dynamics of nutrients, water and individual plants characterised by traits. We then simulated all possible combinations of eight plant species with different levels of diversity to assess the role of plant diversity and traits on multifunctionality, the provision of six ecosystem functions (covering three ecosystem services), as well as trade-offs and synergies among the functions under current and future climatic conditions.Our results show that multifunctionality cannot fully be achieved because of trade-offs among functions that are attributable to sets of traits that affect functions differently. Our measure of multifunctionality was increased by higher levels of planted species richness under current, but not future climatic conditions. In contrast, single functions were differently impacted by increased plant diversity. In addition, we found that trade-offs and synergies among functions shifted with climate change.Synthesis and application. Our results imply that restoration ecologists will face a clear challenge to achieve their targets with respect to multifunctionality not only under current conditions, but also in the long-term. However, once ModEST is parameterized and validated for a specific restoration site, managers can assess which target goals can be achieved given the set of available plant species and site-specific conditions. It can also highlight which species combinations can best achieve long-term improved multifunctionality due to their trait diversity.


2019 ◽  
Vol 26 (2) ◽  
pp. 75-80
Author(s):  
Kuldeep Singh Dogra ◽  
◽  
Sushmita Uniyal ◽  
Kumar Ambrish ◽  
◽  
...  

Indian Western Himalaya has a rich plant diversity/ bio-resources due to the large variations in the altitude (300 to 6000 ms) and climatic conditions from tropical, temperate to alpine. The paper sheds light on the issues and challenges of climate change in the Western Himalaya; its impact on the plant diversity (wild plants, crops, fruits); loss of plant diversity and livelihood of the local communities; impact on the phenology of plant species; possible mitigation strategies to combat the impact of climate change. The Western Himalayan region has a rich diversity of plant diversity or bio resources. These bio resources (wild plants, crops, fruits) have been used by the local communities in the form of traditional medicines and foods from pre-historic periods or since the settlement of human communities in this region. These communities used these bio-resources as a source of income by their cultivation and selling in the markets. They are also involved in the traditional agriculture and horticulture practices and for that dependent on the climatic conditions (rate of precipitation, temperature, humidity) throughout the year. Hence stable environment conditions a pre requisite for better production and productivity. But in the last 100 years an increased in the temperature on earth brought large variation in the climate of Himalayan region too. The extreme climatic conditions will make Himalayan ecosystem more fragile, less productive and more prone towards disasters or natural calamities. Long term planning is required to understand the impact of climate change in the Western Himalaya along with some new strategies to mitigate its impact.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Lotte Korell ◽  
Harald Auge ◽  
Jonathan M. Chase ◽  
W. Stanley Harpole ◽  
Tiffany M. Knight

AbstractMitigating and adapting to climate change requires an understanding of the magnitude and nature by which climate change will influence the diversity of plants across the world’s ecosystems. Experiments can causally link precipitation change to plant diversity change, however, these experiments vary in their methods and in the diversity metrics reported, making synthesis elusive. Here, we explicitly account for a number of potentially confounding variables, including spatial grain, treatment magnitude and direction and background climatic conditions, to synthesize data across 72 precipitation manipulation experiments. We find that the effects of treatments with higher magnitude of precipitation manipulation on plant diversity are strongest at the smallest spatial scale, and in drier environments. Our synthesis emphasizes that quantifying differential responses of ecosystems requires explicit consideration of spatial grain and the magnitude of experimental manipulation. Given that diversity provides essential ecosystem services, especially in dry and semi-dry areas, our finding that these dry ecosystems are particular sensitive to projected changes in precipitation has important implications for their conservation and management.


Planta Medica ◽  
2016 ◽  
Vol 81 (S 01) ◽  
pp. S1-S381
Author(s):  
MD López ◽  
P Jara ◽  
S Fischer ◽  
R Wilckens ◽  
H Serri ◽  
...  

2020 ◽  
pp. 50-64
Author(s):  
Kuladeep Kumar Sadevi ◽  
Avlokita Agrawal

With the rise in awareness of energy efficient buildings and adoption of mandatory energy conservation codes across the globe, significant change is being observed in the way the buildings are designed. With the launch of Energy Conservation Building Code (ECBC) in India, climate responsive designs and passive cooling techniques are being explored increasingly in building designs. Of all the building envelope components, roof surface has been identified as the most significant with respect to the heat gain due to the incident solar radiation on buildings, especially in tropical climatic conditions. Since ECBC specifies stringent U-Values for roof assembly, use of insulating materials is becoming popular. Along with insulation, the shading of the roof is also observed to be an important strategy for improving thermal performance of the building, especially in Warm and humid climatic conditions. This study intends to assess the impact of roof shading on building’s energy performance in comparison to that of exposed roof with insulation. A typical office building with specific geometry and schedules has been identified as base case model for this study. This building is simulated using energy modelling software ‘Design Builder’ with base case parameters as prescribed in ECBC. Further, the same building has been simulated parametrically adjusting the amount of roof insulation and roof shading simultaneously. The overall energy consumption and the envelope performance of the top floor are extracted for analysis. The results indicate that the roof shading is an effective passive cooling strategy for both naturally ventilated and air conditioned buildings in Warm and humid climates of India. It is also observed that a fully shaded roof outperforms the insulated roof as per ECBC prescription. Provision of shading over roof reduces the annual energy consumption of building in case of both insulated and uninsulated roofs. However, the impact is higher for uninsulated roofs (U-Value of 3.933 W/m2K), being 4.18% as compared to 0.59% for insulated roofs (U-Value of 0.33 W/m2K).While the general assumption is that roof insulation helps in reducing the energy consumption in tropical buildings, it is observed to be the other way when insulation is provided with roof shading. It is due to restricted heat loss during night.


2020 ◽  
pp. 7-10
Author(s):  
Vasiliy P. Petropavlovsky ◽  
◽  
Vyacheslav V. Marchenko ◽  
Lyudmila S. Vikulova ◽  
Olga D. Chepeleva ◽  
...  

Summary. Data on distribution of hypodermatosis among large horned cattle in Stavropol region are presented in the article. It was proved that this pathology is widespread in this region. From 12% to 38% of animals from the total number of examined livestock are affected. Ordinary subcutaneous botfly (stroma) Hypoderma bovis de Geer and south subcutaneous botfly (pischevodnik) Hypoderma lineatum de Villers parasites on large horned cattle. The species ratio of gadflies is: Hypoderma bovis (de Gee - 61.1%, Hypoderma lineatum de Villers - 38.9%). The disease is widespread in all climatic zones of Stavropol region. Animals of all age and sex groups are infected, but young animals are more often affected. Linear relationship between the indicators of the transformation of climatic conditions in Stavropol region, the spread of hypodermatosis and the timing of treatment and preventive measures were determined. Authors proved that the complete death of H. bovis and H. lineatum imago (regardless of the time of their hatching) was noted when the temperature drops to -3°C for two days. Thus, this temperature determines the start of treatment and preventive measures against hypodermatosis in the area of animal welfare. When analyzing the histomorphological changes caused by H. bovis and H. lineatum in the body of large horned cattle, perforation of the skin, swelling of adjacent tissues, disorganization of the stroma and structural elements, erythrocyte aggregation, hemorrhages, hydropic degeneration of cellular elements, tissue necrosis, polymorphonuclear leukocyte infiltration of affected organs and tissues were observed. The data on pathogenesis were presented, the analysis of economic damage and the veterinary and sanitary assessment of the products of slaughter of cattle with hypodermatosis were carried out.


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