Quantifying the dynamics of rocky intertidal sessile communities along the Pacific coast of Japan: implications for ecological resilience

AbstractLong-term patterns in trajectories of natural communities provide insights into ecological resilience, but their assessment requires long-term census data. We analyzed 16-year census data for intertidal communities from 30 rocky shores along Japan’s Pacific coast to assign community change to four possible trajectories (stable, reversible, abrupt, or linear) representing different aspects of ecological resilience, and to estimate multiple metrics of temporal invariability (species richness, species composition, and community abundance). We examined (1) how the prevalence of the four trajectories differs among regions, (2) how the features (model coefficients) of each trajectory vary among regions, and (3) how the temporal invariabilities differ among trajectories and regions. We found that the stable trajectory was the most common. Its features differed among regions, with a faster recovery to steady-state equilibrium in low-latitude regions. Furthermore, trajectories and temporal invariabilities both varied among regions, seemingly in association with the strength of ocean current fluctuations. Thus, the relationship between community temporal invariability and trajectory may be weak or absent, at least at the regional scale.

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Similarity of rocky intertidal assemblages along the Pacific coast of Japan: effects of spatial scales and geographic distance

Ecological Research ◽

10.1007/s11284-005-0138-6 ◽

2005 ◽

Vol 21 (3) ◽

pp. 425-435 ◽

Cited By ~ 45

Author(s):

Masahiro Nakaoka ◽

Norihiko Ito ◽

Tomoko Yamamoto ◽

Takehiro Okuda ◽

Takashi Noda

Keyword(s):

Pacific Coast ◽

Spatial Scales ◽

Geographic Distance ◽

Rocky Intertidal ◽

The Pacific ◽

Pacific Coast Of Japan

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Long-term abundance trends of the northern form of the short-finned pilot whale (Globicephala macrorhynchus) along the Pacific coast of Japan

Marine Mammal Science ◽

10.1111/j.1748-7692.2010.00410.x ◽

2010 ◽

Vol 27 (3) ◽

pp. 477-492 ◽

Cited By ~ 11

Author(s):

Yu Kanaji ◽

Hiroshi Okamura ◽

Tomio Miyashita

Keyword(s):

Pacific Coast ◽

Pilot Whale ◽

The Pacific ◽

Abundance Trends ◽

Pacific Coast Of Japan

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Development of a time-series shotgun metagenomics database for monitoring microbial communities at the Pacific coast of Japan

Scientific Reports ◽

10.1038/s41598-021-91615-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Kazutoshi Yoshitake ◽

Gaku Kimura ◽

Tomoko Sakami ◽

Tsuyoshi Watanabe ◽

Yukiko Taniuchi ◽

...

Keyword(s):

Time Series ◽

Microbial Communities ◽

Pacific Coast ◽

Three Dimensional ◽

Amplicon Sequencing ◽

Metagenomic Data ◽

Shotgun Metagenomics ◽

Functional Features ◽

Pacific Coast Of Japan ◽

Marine Microbial Communities

AbstractAlthough numerous metagenome, amplicon sequencing-based studies have been conducted to date to characterize marine microbial communities, relatively few have employed full metagenome shotgun sequencing to obtain a broader picture of the functional features of these marine microbial communities. Moreover, most of these studies only performed sporadic sampling, which is insufficient to understand an ecosystem comprehensively. In this study, we regularly conducted seawater sampling along the northeastern Pacific coast of Japan between March 2012 and May 2016. We collected 213 seawater samples and prepared size-based fractions to generate 454 subsets of samples for shotgun metagenome sequencing and analysis. We also determined the sequences of 16S rRNA (n = 111) and 18S rRNA (n = 47) gene amplicons from smaller sample subsets. We thereafter developed the Ocean Monitoring Database for time-series metagenomic data (http://marine-meta.healthscience.sci.waseda.ac.jp/omd/), which provides a three-dimensional bird’s-eye view of the data. This database includes results of digital DNA chip analysis, a novel method for estimating ocean characteristics such as water temperature from metagenomic data. Furthermore, we developed a novel classification method that includes more information about viruses than that acquired using BLAST. We further report the discovery of a large number of previously overlooked (TAG)n repeat sequences in the genomes of marine microbes. We predict that the availability of this time-series database will lead to major discoveries in marine microbiome research.

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Long-term changes in the plant ecology of an African savanna landscape and the implications for ecosystem theory and conservation management

Ecological Processes ◽

10.1186/s13717-021-00286-5 ◽

2021 ◽

Vol 10 (1) ◽

Author(s):

David Western ◽

Victor N. Mose ◽

David Maitumo ◽

Caroline Mburu

Keyword(s):

Human Impact ◽

National Parks ◽

Conservation Management ◽

Plant Ecology ◽

Ecological Resilience ◽

Pasture Production ◽

Ecosystem Theory ◽

The Impact

Abstract Background Studies of the African savannas have used national parks to test ecological theories of natural ecosystems, including equilibrium, non-equilibrium, complex adaptive systems, and the role of top-down and bottom-up physical and biotic forces. Most such studies have excluded the impact of pastoralists in shaping grassland ecosystems and, over the last half century, the growing human impact on the world’s rangelands. The mounting human impact calls for selecting indicators and integrated monitoring methods able to track ecosystem changes and the role of natural and human agencies. Our study draws on five decades of monitoring the Amboseli landscape in southern Kenya to document the declining role of natural agencies in shaping plant ecology with rising human impact. Results We show that plant diversity and productivity have declined, biomass turnover has increased in response to a downsizing of mean plant size, and that ecological resilience has declined with the rising probability of extreme shortfalls in pasture production. The signature of rainfall and physical agencies in driving ecosystem properties has decreased sharply with growing human impact. We compare the Amboseli findings to the long-term studies of Kruger and Serengeti national parks to show that the human influence, whether by design or default, is increasingly shaping the ecology of savanna ecosystems. We look at the findings in the larger perspective of human impact on African grasslands and the world rangelands, in general, and discuss the implications for ecosystem theory and conservation policy and management. Conclusions The Amboseli study shows the value of using long-term integrated ecological monitoring to track the spatial and temporal changes in the species composition, structure, and function of rangeland ecosystems and the role of natural and human agencies in the process of change. The study echoes the widespread changes underway across African savannas and world’s rangelands, concluding that some level of ecosystem management is needed to prevent land degradation and the erosion of ecological function, services, and resilience. Despite the weak application of ecological theory to conservation management, a plant trait-based approach is shown to be useful in explaining the macroecological changes underway.

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Long-term ocean acidification trends in coastal waters around Japan

Scientific Reports ◽

10.1038/s41598-021-84657-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Hiroshi Ishida ◽

Ryosuke S. Isono ◽

Jun Kita ◽

Yutaka W. Watanabe

Keyword(s):

Pacific Ocean ◽

Ocean Acidification ◽

Sea Of Japan ◽

Ocean Current ◽

The Sea Of Japan ◽

Marginal Seas ◽

The Pacific ◽

Activity Measurements ◽

The Pacific Ocean

AbstractThis study examines long-term ocean pH data to evaluate ocean acidification (OA) trends at two coastal research institutions located on the Sea of Japan and the Pacific Ocean. These laboratories are located away from the influences of large rivers and major industrial activity. Measurements were performed daily for the past 30 years (1980s–2010s). The average annual ocean pH for both sites showed generally negative trends. These trends were – 0.0032 and – 0.0068 year–1 (p < 0.001) at the Sea of Japan and Pacific Ocean sites, respectively. The trends were superimposed onto approximately 10-year oscillations, which appear to synchronize with the ocean current periodicity. At the Sea of Japan site, the ocean pH in the summer was higher, and the rate of OA was higher than during other seasons. Our results suggest that seasonality and ocean currents influence OA in the coastal areas of open oceans and can affect the coastal regions of marginal seas.

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Role of reservoir regulation and groundwater feedback in a simulated ground‐soil‐vegetation continuum: A long‐term regional scale analysis

Hydrological Processes ◽

10.1002/hyp.14341 ◽

2021 ◽

Author(s):

Jianhui Wei ◽

Ningpeng Dong ◽

Benjamin Fersch ◽

Joël Arnault ◽

Sven Wagner ◽

...

Keyword(s):

Regional Scale ◽

Scale Analysis ◽

Reservoir Regulation ◽

Vegetation Continuum

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Calcareous nannoplankton ecology and community change across the Paleocene-Eocene Thermal Maximum

Paleobiology ◽

10.1666/12050 ◽

2013 ◽

Vol 39 (4) ◽

pp. 628-647 ◽

Cited By ~ 19

Author(s):

Leah J. Schneider ◽

Timothy J. Bralower ◽

Lee R. Kump ◽

Mark E. Patzkowsky

Keyword(s):

Nutrient Availability ◽

Multivariate Analyses ◽

Geochemical Modeling ◽

Community Change ◽

Open Ocean ◽

Data Set ◽

Long Term Effect ◽

Term Change ◽

Thermal Maximum

The Paleocene-Eocene Thermal Maximum (PETM; ca. 55.8 Ma) is thought to coincide with a profound but entirely transient change among nannoplankton communities throughout the ocean. Here we explore the ecology of nannoplankton during the PETM by using multivariate analyses of a global data set that is based upon the distribution of taxa in time and space. We use these results, coupled with stable isotope data and geochemical modeling, to reinterpret the ecology of key genera. The results of the multivariate analyses suggest that the community was perturbed significantly in coastal and high-latitudes sites compared to the open ocean, and the relative influence of temperature and nutrient availability on the assemblage varies regionally. The open ocean became more stratified and less productive during the PETM and the oligotrophic assemblage responded primarily to changes in nutrient availability. Alternatively, assemblages at the equator and in the Southern Ocean responded to temperature more than to nutrient reduction. In addition, the assemblage change at the PETM was not merely transient—there is evidence of adaptation and a long-term change in the nannoplankton community that persists after the PETM and results in the disappearance of a high-latitude assemblage. The long-term effect on communities caused by transient warming during the PETM has implications for modern-day climate change, suggesting similar permanent changes to nannoplankton community structure as the oceans warm.

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THE RAILWAY NETWORK AND THE PROCESS OF POPULATION CONCENTRATION IN SPAIN, 1900-2001

Revista de Historia Económica / Journal of Iberian and Latin American Economic History ◽

10.1017/s0212610914000160 ◽

2014 ◽

Vol 32 (3) ◽

pp. 351-379 ◽

Cited By ~ 2

Author(s):

Xavier Franch-Auladell ◽

Mateu Morillas-Torné ◽

Jordi Martí-Henneberg

Keyword(s):

Total Population ◽

Census Data ◽

Population Distribution ◽

Historical Analysis ◽

Railway Network ◽

Population Concentration ◽

Central Hypothesis ◽

Municipal Level

ABSTRACTThis paper proposes a methodology for quantifying the territorial impact on population distribution of the railway. The central hypothesis is that access to railway services provides the best-connected areas with a long-term comparative advantage over others that are less accessible. Carrying out a historical analysis and providing comparable data at the municipal level allows us to determine the extent to which the railway has fostered the concentration of population within its immediate surroundings. The case study presented here is that of Spain between 1900 and 2001, but the same methodology could equally be applied to any other country for which the required data are available. In this case, key data included a Geographic Information System with information about both the development of the railway network and census data relating to total population at the municipal level. The results obtained suggest the relevance of this methodology, which makes it possible to identify the periods and areas in which this influence was most significant.

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