scholarly journals Tropical islands of the Anthropocene: Deep histories of anthropogenic terrestrial–marine entanglement in the Pacific and Caribbean

2021 ◽  
Vol 118 (40) ◽  
pp. e2022209118 ◽  
Author(s):  
Scott M. Fitzpatrick ◽  
Christina M. Giovas
Keyword(s):  
Tropical Forests ◽  
Model Systems ◽  
Anthropogenic Effects ◽  
Tropical Islands ◽  
Deep Time ◽  
Environmental Interactions ◽  
The Pacific ◽  
Near Shore ◽  
Cultural Responses

Islands are useful model systems for examining human–environmental interactions. While many anthropogenic effects visible in the archaeological and paleoecological records are terrestrial in nature (e.g., clearance of tropical forests for agriculture and settlement; introduction of nonnative flora and fauna), native peoples also relied heavily on marine environments for their subsistence and livelihood. Here we use two island case studies—Palau (Micronesia) and the Lesser Antilles (Caribbean)—and approach their long-term settlement history through a “ridge-to-reef” perspective to assess the role that human activity played in land- and seascape change over deep time. In particular, we examine the entanglement of terrestrial and marine ecosystems resulting from anthropogenic effects and cultural responses to socio-environmental feedback. We suggest that on the humanized tropical islands of the Anthropocene, mangroves, near shore and littoral areas, and coral reefs were major sites of terrestrial–marine interface chronicling and modulating anthropogenic effects.

scholarly journals Long-Term Nitrogen Addition Decreases Soil Carbon Mineralization in an N-Rich Primary Tropical Forest

Forests ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 734
Author(s):  
Xiankai Lu ◽  
Qinggong Mao ◽  
Zhuohang Wang ◽  
Taiki Mori ◽  
Jiangming Mo ◽  
...  
Keyword(s):  
Microbial Biomass ◽  
Organic Carbon ◽  
Tropical Forest ◽  
Soil Carbon ◽  
Tropical Forests ◽  
Carbon Mineralization ◽  
N Deposition ◽  
Soil Carbon Mineralization ◽  
N Additions

Anthropogenic elevated nitrogen (N) deposition has an accelerated terrestrial N cycle, shaping soil carbon dynamics and storage through altering soil organic carbon mineralization processes. However, it remains unclear how long-term high N deposition affects soil carbon mineralization in tropical forests. To address this question, we established a long-term N deposition experiment in an N-rich lowland tropical forest of Southern China with N additions such as NH4NO3 of 0 (Control), 50 (Low-N), 100 (Medium-N) and 150 (High-N) kg N ha−1 yr−1, and laboratory incubation experiment, used to explore the response of soil carbon mineralization to the N additions therein. The results showed that 15 years of N additions significantly decreased soil carbon mineralization rates. During the incubation period from the 14th day to 56th day, the average decreases in soil CO2 emission rates were 18%, 33% and 47% in the low-N, medium-N and high-N treatments, respectively, compared with the Control. These negative effects were primarily aroused by the reduced soil microbial biomass and modified microbial functions (e.g., a decrease in bacteria relative abundance), which could be attributed to N-addition-induced soil acidification and potential phosphorus limitation in this forest. We further found that N additions greatly increased soil-dissolved organic carbon (DOC), and there were significantly negative relationships between microbial biomass and soil DOC, indicating that microbial consumption on soil-soluble carbon pool may decrease. These results suggests that long-term N deposition can increase soil carbon stability and benefit carbon sequestration through decreased carbon mineralization in N-rich tropical forests. This study can help us understand how microbes control soil carbon cycling and carbon sink in the tropics under both elevated N deposition and carbon dioxide in the future.

scholarly journals Long Term Memory Outcome of Repetitive, Low-Level Dietary Exposure to Domoic Acid in Native Americans

2021 ◽  
Vol 18 (8) ◽  
pp. 3955
Author(s):  
Lynn M. Grattan ◽  
Laura Kaddis ◽  
J. Kate Tracy ◽  
John Glenn Morris
Keyword(s):  
Native Americans ◽  
Domoic Acid ◽  
Dietary Exposure ◽  
Long Term Memory ◽  
Shellfish Poisoning ◽  
Amnesic Shellfish Poisoning ◽  
The Pacific ◽  
Small Decline ◽  
Speed And Accuracy

Domoic acid (DA) is a marine-based neurotoxin that, if ingested via tainted shellfish, is associated with Amnesic Shellfish Poisoning (ASP). These acute effects of elevated DA exposure in humans have been well described. In contrast, the long-term impacts of lower level, repetitive, presumably safe doses of DA (less than 20 ppm) are minimally known. Since Native Americans (NA) residing in coastal communities of the Pacific NW United States are particularly vulnerable to DA exposure, this study focuses on the long-term, 8-year memory outcome associated with their repeated dietary consumption of the neurotoxin. Measures of razor clam consumption, memory, clerical speed and accuracy, and depression were administered over eight years to 500 randomly selected adult NA men and women ages 18–64. Data were analyzed using GEE analyses taking into consideration the year of study, demographic factors, and instrumentation in examining the association between dietary exposure and outcomes. Findings indicated a significant but small decline in total recall memory within the context of otherwise stable clerical speed and accuracy and depression scores. There is reason to believe that a continuum of memory difficulties may be associated with DA exposure, rather than a unitary ASP syndrome.

scholarly journals Long-term ocean acidification trends in coastal waters around Japan

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.

Changes in microbial dynamics during long-term decomposition in tropical forests

2013 ◽  
Vol 66 ◽  
pp. 60-68 ◽  
Author(s):  
Kristen M. DeAngelis ◽  
Dylan Chivian ◽  
Julian L. Fortney ◽  
Adam P. Arkin ◽  
Blake Simmons ◽  
...  
Keyword(s):  
Tropical Forests ◽  
Microbial Dynamics

Agrodeforestation and the loss of agrobiodiversity in the Pacific Islands: a call for conservation

2014 ◽  
Vol 20 (2) ◽  
pp. 180 ◽  
Author(s):  
Randolph Thaman
Keyword(s):  
Biodiversity Conservation ◽  
Sustainable Management ◽  
Pacific Islands ◽  
Agricultural Land ◽  
Ecosystem Goods And Services ◽  
Livelihood Security ◽  
Goods And Services ◽  
The Pacific ◽  
Aichi Biodiversity Targets

Our ability to conserve biodiversity and to adapt to climate, environmental and economic change in the Pacific Islands will be greatly dependent on the conservation, restoration and enrichment of biodiversity within traditional multispecies agricultural land use systems. “Agrobiodiversity” is the most well-known, culturally-useful and accessible biodiversity on most islands and constitutes the most important foundation for ecosystem goods and services that support food, health, energy and livelihood security. This rich Pacific agrobiodiversity heritage, including associated ethnobiodiversity is highly threatened and deserves more prominence in mainstream conservation initiatives as a foundation for long-term sustainability. Such action is in line with Aichi Biodiversity Targets 7 and 13 which set goals for sustainable management of agriculture, fisheries and forestry, and the maintenance of genetic diversity as critical for successful biodiversity conservation globally. It is also supported by the findings of the Japan Satoyama-Satoumi Assessment, which stresses the critical importance of biodiversity conservation and ecosystem services provided by traditional agricultural and village landscapes.

“The ice has gone”: Vernacular meteorology, fisheries and human–ice relationships on Sakhalin Island

Polar Record ◽  
2021 ◽  
Vol 57 ◽  
Author(s):  
Nadezhda Mamontova
Keyword(s):  
Well Being ◽  
Community Based ◽  
Rural People ◽  
The Past ◽  
Weather Observations ◽  
The Pacific ◽  
Management Policies ◽  
Subsistence Activities ◽  
Human Subsistence

Abstract This paper examines vernacular weather observations amongst rural people on Sakhalin, Russia’s largest island on the Pacific Coast, and their relationship to the ice. It is based on a weather diary (2000–2016) of one of the local inhabitants and fieldwork that the author conducted in the settlement of Trambaus in 2016. The diary as a community-based weather monitoring allows us to examine how people understand, perceive and deal with the weather both daily and in the long-term perspective. Research argues that amongst all natural phenomena, the ice is the most crucial for the local inhabitants as it determines human subsistence activities, navigation and relations with other environmental forces and beings. People perceive the ice as having an agency, engage in a dialogue with it, learn and adjust themselves to its drifting patterns. Over the past decade, the inability to predict the ice’s behaviour has become a major problem affecting people’s well-being in the settlement. The paper advocates further integrating vernacular weather observations and their relations with natural forces into research on climate change and local fisheries management policies.

Northeast Atlantic storminess in centennial reanalyses

2021 ◽  
Author(s):  
Oliver Krueger ◽  
Frauke Feser ◽  
Christopher Kadow ◽  
Ralf Weisse
Keyword(s):  
Climate Models ◽  
Numerical Models ◽  
Geostrophic Wind ◽  
Model Systems ◽  
Storm Activity ◽  
Northeast Atlantic ◽  
Wind Speeds ◽  
Long Term Trends ◽  
Storm Index

&lt;p&gt;Global atmospheric reanalyses are commonly applied for the validation of climate models, diagnostic studies, and driving higher resolution numerical models with the emphasis on assessing climate variability and long-term trends. Over recent years, longer reanalyses spanning a period of more than hundred years have become available. In this study, the variability and long-term trends of storm activity is assessed over the northeast Atlantic in modern centennial reanalysis datasets, namely ERA-20cm, ERA-20c, CERA-20c, and the 20CR-reanalysis suite with 20CRv3 being the most recent one. All reanalyses, except from ERA-20cm, assimilate surface pressure observations, whereby ERA-20C and CERA-20c additionally assimilate surface winds. For the assessment, the well-established storm index of higher annual percentiles of geostrophic wind speeds derived from pressure observations at sea level over a relatively densely monitored marine area is used.&lt;/p&gt;&lt;p&gt;The results indicate that the examined centennial reanalyses are not able to represent long-term trends of storm activity over the northeast Atlantic, particularly in the earlier years of the period examined when compared with the geostrophic wind index based on pressure observations. Moreover, the reanalyses show inconsistent long-term behaviour when compared with each other. Only in the latter half of the 20th century, the variability of reanalysed and observed storminess time series starts to agree with each other. Additionally, 20CRv3, the most recent centennial reanalysis examined, shows markedly improved results with increased uncertainty, albeit multidecadal storminess variability does not match observed values in earlier times before about 1920.&lt;/p&gt;&lt;p&gt;The behaviour shown by the centennial reanalyses are likely caused by the increasing number of assimilated observations, changes in the observational databases used, and the different underlying numerical model systems. Furthermore, the results derived from the ERA-20cm reanalysis that does not assimilate any pressure or wind observations suggests that the variability and uncertainty of storminess over the northeast Atlantic is high making it difficult to determine storm activity when numerical models are not bound by observations. The results of this study imply and reconfirm previous findings that the assessment of long-term storminess trends and variability in centennial reanalyses remains a rather delicate matter, at least for the northeast Atlantic region.&lt;/p&gt;

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