The relationship between proportion of endemics and species diversity on islands: expectations from a null model

Ecography ◽  
2008 ◽  
Vol 0 (0) ◽  
pp. 080227084236895-0
Author(s):  
Ayşegül Birand ◽  
Daniel J. Howard
Keyword(s):  
Species Diversity ◽  
Null Model ◽  
The Relationship

scholarly journals Soil Nutrient and Vegetation Diversity Patterns of Alpine Wetlands on the Qinghai-Tibetan Plateau

2021 ◽  
Vol 13 (11) ◽  
pp. 6221
Author(s):  
Muyuan Ma ◽  
Yaojun Zhu ◽  
Yuanyun Wei ◽  
Nana Zhao
Keyword(s):  
Species Diversity ◽  
Tibetan Plateau ◽  
Soil Properties ◽  
Soil Ph ◽  
Plant Biomass ◽  
Principal Component ◽  
Vegetation Diversity ◽  
Vegetation Biomass ◽  
Relative Contribution ◽  
The Relationship

To predict the consequences of environmental change on the biodiversity of alpine wetlands, it is necessary to understand the relationship between soil properties and vegetation biodiversity. In this study, we investigated spatial patterns of aboveground vegetation biomass, cover, species diversity, and their relationships with soil properties in the alpine wetlands of the Gannan Tibetan Autonomous Prefecture of on the Qinghai-Tibetan Plateau, China. Furthermore, the relative contribution of soil properties to vegetation biomass, cover, and species diversity were compared using principal component analysis and multiple regression analysis. Generally, the relationship between plant biomass, coverage, diversity, and soil nutrients was linear or unimodal. Soil pH, bulk density and organic carbon were also significantly correlated to plant diversity. The soil attributes differed in their relative contribution to changes in plant productivity and diversity. pH had the highest contribution to vegetation biomass and species richness, while total nitrogen was the highest contributor to vegetation cover and nitrogen–phosphorus ratio (N:P) was the highest contributor to diversity. Both vegetation productivity and diversity were closely related to soil properties, and soil pH and the N:P ratio play particularly important roles in wetland vegetation biomass, cover, and diversity.

The relationship between species diversity and functional diversity along aridity gradients in semi-arid rangeland

2021 ◽  
Vol 195 ◽  
pp. 104632
Author(s):  
Guy Dovrat ◽  
Ehud Meron ◽  
Moshe Shachak ◽  
Yosef Moshe ◽  
Yagil Osem
Keyword(s):  
Species Diversity ◽  
Functional Diversity ◽  
The Relationship ◽  
Semi Arid ◽  
Arid Rangeland

scholarly journals Data assimilation in Agent-based models using creation and annihilation operators

2019 ◽  
Author(s):  
Daniel Tang
Keyword(s):  
Real World ◽  
Null Model ◽  
The State ◽  
Actual State ◽  
Agent Based Models ◽  
Agent Based ◽  
Predator Prey ◽  
Predator Prey Model ◽  
The One ◽  
The Relationship

Agent-based models are a powerful tool for studying the behaviour of complex systems that can be described in terms of multiple, interacting ``agents''. However, because of their inherently discrete and often highly non-linear nature, it is very difficult to reason about the relationship between the state of the model, on the one hand, and our observations of the real world on the other. In this paper we consider agents that have a discrete set of states that, at any instant, act with a probability that may depend on the environment or the state of other agents. Given this, we show how the mathematical apparatus of quantum field theory can be used to reason probabilistically about the state and dynamics the model, and describe an algorithm to update our belief in the state of the model in the light of new, real-world observations. Using a simple predator-prey model on a 2-dimensional spatial grid as an example, we demonstrate the assimilation of incomplete, noisy observations and show that this leads to an increase in the mutual information between the actual state of the observed system and the posterior distribution given the observations, when compared to a null model.

Biodiversity, Distributions, and Extinction

2013 ◽  
Author(s):  
Eric Post
Keyword(s):  
Climate Change ◽  
Species Diversity ◽  
Time Scales ◽  
Upper And Lower Bounds ◽  
Ecosystem Goods And Services ◽  
Goods And Services ◽  
Local Diversity ◽  
Rapid Climate Change ◽  
The Subject ◽  
The Relationship

This chapter examines the relationship between species diversity and ecosystem function and stability. This subject is currently one of the most intensely studied topics in ecology. It is also of paramount importance in the study of the ecological consequences of climate change, most probably because of its obvious relevance to ecosystem goods and services. More classically, however, the subject of biodiversity response to climate change relates to what factors set limits to the upper and lower bounds of species diversity and how those factors might be altered by rapid climate change. Of the two processes generating diversity—speciation and immigration—the latter obviously operates at shorter time scales and is likely to respond more immediately to climate change. Of the processes reducing local diversity—extinction and emigration—the latter is, again, likely to operate at shorter time scales, but both processes are likely to be influenced by climate change, although at potentially different timescales.

Sprouting, succession and tree species diversity in a South African coastal dune forest

2011 ◽  
Vol 27 (2) ◽  
pp. 195-203 ◽  
Author(s):  
Emmanuel Fred Nzunda
Keyword(s):  
Species Diversity ◽  
South African ◽  
Coastal Dune ◽  
Regeneration Pattern ◽  
Disturbance Frequency ◽  
Structural Variables ◽  
Chronic Disturbance ◽  
Diameter Frequency Distribution ◽  
Shifting Cultivators ◽  
The Relationship

Abstract:Sprouting may play a significant role in maintenance of plant diversity where prevailing disturbance frequency and severity allows. When disturbance frequency and severity decrease, strong sprouters may be outcompeted. As a result, species composition and diversity may change. This study was carried out to investigate the relationship between sprouting, succession and species diversity in a coastal dune forest that currently suffers from low-severity, chronic disturbance due to sea winds and loose sand substrate. Historically, the site was occupied by shifting cultivators who left the site about 80 y ago. Data on trees that were at least 1.3 m tall from 42 sample plots measuring 20 × 20 m were used. The plots were ranked in order of advancement of succession using the first axis of Principal Components Analysis of forest structural variables. Regeneration pattern was examined using analysis of stem diameter frequency distribution. Abundance and regeneration of strong basal sprouters, incidence of basal sprouting and species diversity decreased with advancement of succession. Only a few species could regenerate under the canopy of late-successional sites. Basal sprouts decreased with advancement of succession whereas trunk sprouts increased. These results suggest that maintenance of high species diversity may need a level of disturbance that allows regeneration and maintenance of strong basal sprouters.

Species diversity: a new null model

Cladistics ◽  
2002 ◽  
Vol 18 (5) ◽  
pp. 537-538
Author(s):  
E PIANKA
Keyword(s):  
Species Diversity ◽  
Null Model

The Care Work of Balance

Inner Asia ◽  
2020 ◽  
Vol 22 (2) ◽  
pp. 237-254
Author(s):  
Alex Oehler
Keyword(s):  
Species Diversity ◽  
Ethic Of Care ◽  
Domestic Animals ◽  
Care Work ◽  
Hybrid Breeding ◽  
Breeding Practices ◽  
Anthropological Literature ◽  
The Relationship

Abstract This paper explores the relationship between herding and hunting practices in the mountainous environment of Indigenous Soyots of Okinskii Raion (Oka), Buryatia. It traces an animistic approach to the concept of balance among sentient entities, including landscapes, identifying it as an underlying ethic governing the relationships of domestic and non-domestic animals with humans. Drawing on this ethic of care, the paper identifies practices directed at achieving balance as a form of resistance to assertions of outright control over living beings. The author begins by problematising the concept of care, pointing to basic ontological differences identified in anthropological literature, before addressing how care and balance are related. Here care is understood as a matter of attentiveness: a skill that links herding and hunting practices. The paper then delves into three concrete areas of care: the care of creating life in living and calving spaces; the care of holding life together through material implements and invocation of intangible protective forces; and, finally, care for species diversity in local yak and hybrid breeding practices.

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