Identifying demographic and environmental drivers of recruitment and population growth in a cavity-nesting sea duck population

2017 ◽  
Vol 48 (11) ◽  
pp. 1394-1405 ◽  
Author(s):  
Abigail J. Lawson ◽  
James S. Sedinger ◽  
Eric J. Taylor
Keyword(s):  
Population Growth ◽  
Environmental Drivers ◽  
Cavity Nesting ◽  
Sea Duck

scholarly journals The demographic buffering strategy has a threshold of effectiveness to increases in environmental stochasticity

2020 ◽  
Author(s):  
R.C. Rodríguez-Caro ◽  
P. Capdevila ◽  
E. Graciá ◽  
J. M. Barbosa ◽  
A. Giménez ◽  
...  
Keyword(s):  
Growth Rate ◽  
Population Growth ◽  
Temporal Variation ◽  
Population Growth Rate ◽  
Environmental Stochasticity ◽  
Environmental Data ◽  
Vital Rate ◽  
Environmental Drivers ◽  
List Type ◽  
Animal Populations

AbstractAnimal populations have developed multiple strategies to deal with environmental change. Among them, the demographic buffering strategy consists on constraining the temporal variation of the vital rate(s) (e.g., survival, growth, reproduction) that most affect(s) the overall performance of the population. Given the increase in environmental stochasticity of the current global change scenario, identifying the thresholds beyond which populations are not able to remain viable -despite their potential buffering strategies- is of utmost importance.Tortoises are known to buffer the temporal variation in survival (i.e. this vital rate has the highest contribution to the population growth rate λ) at the expense of a high variability on reproductive rates (lowest contribution to λ). To identify the potential threshold in buffering ability, here we use field data collected across a decade on 15 locations of Testudo graeca along South-Eastern Spain. We analyse the effects of environmental variables (precipitation, temperature, and NDVI) on the probability of laying eggs and the number of eggs per clutch. Finally, we couple the demographic and environmental data to parametrise integral projection models (IPMs) to simulate the effects of different scenarios of drought recurrence on population growth rate.We find that droughts negatively affect the probability of laying eggs, but the overall effects on the population growth rates of T. graeca under the current drought frequencies (one per decade) are negligible. However, increasing the annual frequency of droughts decreases the buffering ability of T. graeca populations, with a threshold at three droughts per decade.Although some species may buffer current environmental regimes by carefully orchestrating how their vital rates vary through time, a demographic buffering strategy may alone not warrant population viability in extreme regimes. Our findings support the hypothesis that the buffering strategy indeed has a threshold of effectiveness. Our methodological approach also provides a useful pipeline for ecologists and managers to determine how effective the management of environmental drivers can be for demographically buffering populations, and which scenarios may not provide long-term species persistence.

scholarly journals Reduced growth with increased quotas of particulate organic and inorganic carbon in the coccolithophore <i>Emiliania huxleyi</i> under future ocean climate change conditions

2020 ◽  
Author(s):  
Yong Zhang ◽  
Sinéad Collins ◽  
Kunshan Gao
Keyword(s):  
Growth Rate ◽  
Population Growth ◽  
Ocean Acidification ◽  
Population Growth Rate ◽  
Inorganic Carbon ◽  
Inorganic Nitrogen ◽  
Emiliania Huxleyi ◽  
Environmental Drivers ◽  
Nutrient Concentrations ◽  
Organic And Inorganic Carbon

Abstract. Effects of ocean acidification and warming on marine primary producers can be modulated by other environmental factors, such as levels of nutrients and light. Here, we investigated the interactive effects of five oceanic environmental drivers (CO2, temperature, light, dissolved inorganic nitrogen and phosphate) on growth rate, particulate organic (POC) and inorganic (PIC) carbon quotas of the cosmopolitan coccolithophore Emiliania huxleyi. Population growth rate increased with increasing temperature (16 to 20 °C) and light intensities (60 to 240 μmol photons m−2  s−1), but decreased with elevated pCO2 concentrations (370 to 960 μatm) and reduced availability of nitrate (24.3 to 7.8 μmol L−1) and phosphate (1.5 to 0.5 μmol L−1). POC quotas were predominantly enhanced by combined effects of increased pCO2 and decreased availability of phosphate. PIC quotas increased with decreased availability of nitrate and phosphate. Our results show that concurrent changes in nutrient concentrations and pCO2 levels predominantly affected growth, photosynthetic carbon fixation and calcification of E. huxleyi, and imply that plastic responses to progressive ocean acidification, warming and decreasing availability of nitrate and phosphate reduce population growth rate while increasing cellular quotas of particulate organic and inorganic carbon of E. huxleyi, ultimately affecting coccolithophore-related ecological and biogeochemical processes.

scholarly journals Drivers of large-scale spatial demographic variation in a perennial plant

2020 ◽  
Author(s):  
Gesa Römer ◽  
Ditte M. Christiansen ◽  
Hendrik de Buhr ◽  
Kristoffer Hylander ◽  
Owen R. Jones ◽  
...  
Keyword(s):  
Growth Rate ◽  
Population Dynamics ◽  
Environmental Factors ◽  
Population Growth ◽  
Spatial Variation ◽  
Population Growth Rate ◽  
Forest Understory ◽  
Environmental Drivers ◽  
Vital Rates ◽  
The Impact

AbstractTo understand how the environment drives spatial variation in population dynamics, we need to assess the effects of a large number of potential drivers on the vital rates (survival, growth and reproduction), and explore these relationships over large geographical areas and long environmental gradients. In this study, we examined the effects of a broad variety of abiotic and biotic environmental factors, including intraspecific density, on the demography of the forest understory herb Actaea spicata between 2017 and 2019 at 40 sites across Sweden, including the northern range margin of its distribution. We assessed the effect of potential environmental drivers on vital rates using generalized linear mixed models (GLMMs), and then quantified the impact of each important driver on population growth rate (λ) using integral projection models (IPMs). Population dynamics of A. spicata were mostly driven by environmental factors affecting survival and growth, such as air humidity, soil depth and forest tree species composition, and thus those drivers jointly determined the realized niche of the species. Soil pH had a strong effect on the flowering probability, while the effect on population growth rate was relatively small. In addition to identifying specific drivers for A. spicata’s population dynamics, our study illustrates the impact that spatial variation in environmental conditions can have on λ. Assessing the effects of a broad range of potential drivers, as done in this study, is important not only to quantify the relative importance of different drivers for population dynamics but also to understand species distributions and abundance patterns.

scholarly journals Reduced growth with increased quotas of particulate organic and inorganic carbon in the coccolithophore <i>Emiliania huxleyi</i> under future ocean climate change conditions

2020 ◽  
Vol 17 (24) ◽  
pp. 6357-6375
Author(s):  
Yong Zhang ◽  
Sinéad Collins ◽  
Kunshan Gao
Keyword(s):  
Growth Rate ◽  
Population Growth ◽  
Ocean Acidification ◽  
Population Growth Rate ◽  
Inorganic Carbon ◽  
Inorganic Nitrogen ◽  
Emiliania Huxleyi ◽  
Environmental Drivers ◽  
Nutrient Concentrations ◽  
Organic And Inorganic Carbon

Abstract. Effects of ocean acidification and warming on marine primary producers can be modulated by other environmental factors, such as levels of nutrients and light. Here, we investigated the interactive effects of five oceanic environmental drivers (CO2, temperature, light, dissolved inorganic nitrogen and phosphate) on the growth rate, particulate organic carbon (POC) and particulate inorganic carbon (PIC) quotas of the cosmopolitan coccolithophore Emiliania huxleyi. The population growth rate increased with increasing temperature (16 to 20 ∘C) and light intensities (60 to 240 µmolphotonsm-2s-1) but decreased with elevated pCO2 concentrations (370 to 960 µatm) and reduced availability of nitrate (24.3 to 7.8 µmol L−1) and phosphate (1.5 to 0.5 µmol L−1). POC quotas were predominantly enhanced by the combined effects of increased pCO2 and decreased availability of phosphate. PIC quotas increased with decreased availability of nitrate and phosphate. Our results show that concurrent changes in nutrient concentrations and pCO2 levels predominantly affected the growth, photosynthetic carbon fixation and calcification of E. huxleyi and imply that plastic responses to progressive ocean acidification, warming, and decreasing availability of nitrate and phosphate reduce the population growth rate while increasing cellular quotas of particulate organic and inorganic carbon of E. huxleyi, ultimately affecting coccolithophore-related ecological and biogeochemical processes.

Red Heart Disease in Pines Caused by Porodaedalea (Phellinus) pini in Florida

EDIS ◽  
2020 ◽  
Vol 2020 (1) ◽  
pp. 3
Author(s):  
Yin-Tse Huang ◽  
Jeffrey Eickwort ◽  
Jiri Hulcr
Keyword(s):  
Heart Disease ◽  
Forest Resources ◽  
Fact Sheet ◽  
Cavity Nesting ◽  
Pine Species

All pine species in Florida are susceptible to red heart disease. The disease can decrease timber value and weaken trees, making them threats to people and property. In forests, however, the same disease can be beneficial to cavity-nesting animals like red-cockaded woodpeckers. This 3-page fact sheet written by Yin-Tse Huang, Jeffrey Eickwort, and Jiri Hulcr and published by the UF/IFAS School of Forest Resources and Conservation describes the disease and provides some tips to manage it in areas where it could cause problems for people.http://edis.ifas.ufl.edu/fr425

İstanbul İlçelerinin Nüfus Değişimi ve Kütük Bilgilerinin Analizi

2019 ◽  
Vol 6 (1) ◽  
pp. 37-72
Author(s):  
Ulaş Sunata ◽  
Dila Ergül
Keyword(s):  
Population Growth ◽  
Population Growth Rate ◽  
Population Change ◽  
Urban Migration ◽  
Specific Population ◽  
Related Factors ◽  
Internal Migrant ◽  
Level Analysis ◽  
Study District ◽  
Demographic Features

39 ilçesiyle Türkiye’nin en büyük nüfusuna sahip ili İstanbul aynı zamanda Türkiye’nin en çok iç göç alan şehridir. Özellikle kırdan kente göç bağlamında sosyo-ekonomik ve demografik özellikleriyle birçok araştırmaya konu olmuştur. Fakat İstanbul yerleşik nüfusunun Türkiye’nin diğer şehirlerine kayıtlı olma yoğunluğu da önemlidir. Bu çalışmanın amacı 2012 ve 2017 yıllarındaki nüfus değişimini göz önünde bulundurarak İstanbul ilçelerinin ayrıntılı nüfus yoğunluğu ve büyüme analizini yapmak, ilgili faktörleri değerlendirmek, hemşehri ağlarını okumak adına yerleşik nüfus kütük bilgileri bakımından inceleyerek elde edilen örüntüler doğrultusunda ilçe tipolojileri oluşturmaktır. Çalışmanın birinci bölümünde ilgili beş yıllık nüfus değişimlerine göre İstanbul ilçe nüfusları analiz edilmiştir. Ardından her bir ilçe için nüfusa kayıtlı olunan kente göre nüfus büyüme hızlarına bakılarak ilçelerin ağırlıklı olarak barındırdığı hemşehri ağları belirlenmiştir. İkinci bölümde ise ilçeler nüfus değişim özelliklerine göre belirli kategorilere ayrılmış ve bu kategoriler doğrultusunda ilçe tipolojileri oluşturulmuştur..ABSTRACT IN ENGLISHA District Level Analysis of Istanbul’s Population Change (2012-2017)Istanbul having the largest population of Turkey with its 39 districts is the most internal-migrant-receiving city in Turkey. Particularly in the context of rural-to-urban migration, Istanbul has been became a subject of various researches with its socio-economic and demographic features. However, the density of Istanbul’s settled population who registered other cities of Turkey is important. The main aim of this study is to analyse population growth of all districts considering the population change between 2012 and 2017, to evaluate the related factors and to develop a district typology by using the data of settled population according to their family registration in the name of reading the current countryman networks. In the first section of the study, district populations of Istanbul are examined regarding the related five-year change. Afterwards, most repeated countryman networks of all Istanbul’s districts are specified regarding the population growth rate of the registered cities. In the latter section of the study, districts were divided into categories regarding the specific population change features which help to create district typology.

Sign in / Sign up

Export Citation Format

Share Document