Holocene changes in forest composition in northern Patagonia responded to climate with little impact of disturbance

AbstractForests in Northeast China in the Greater and Lesser Khingan Mountains (GKM and LKM) account for nearly 1/3 of the total state-owned forests in the country. Regional and historical comparisons of forest plants and macrofungi will favor biological conservation, forest management and economic development. A total of 1067 sampling plots were surveyed on forest composition and structure, with a macrofungi survey at Liangshui and Huzhong Nature Reserves in the center of two regions. Regional and historical differences of these parameters were analyzed with a redundancy ordination of their complex associations. There were 61–76 families, 189–196 genera, and 369–384 species, which was only 1/3 of the historical records. The same dominant species were larch and birch with Korean pine (a climax species) less as expected from past surveys in the LKM. Shrub and herb species were different in the two regions, as expected from historical records. There was 10–50% lower species diversity (except for herb evenness), but 1.8- to 4-time higher macrofungi diversity in the GKM. Compared with the LKM, both tree heights and macrofungi density were higher. Nevertheless, current heights averaging 10 m are half of historical records (> 20 m in the 1960s). Edible macrofungi were the highest proportion in both regions, about twice that of other fungal groups, having important roles in the local economy. A major factor explaining plant diversity variations in both regions was herb cover, followed by shrubs in the GKM and herb-dominant species in the LKM. Factors responsible for macrofungi variations were tree density and shrub height. Vaccinium vitis-idaea and Larix gmelinii in the GKM but tree size and diversity were important factors in the LKM. Our findings highlighted large spatial and historical differences between the GKM and LKM in plant-macrofungal composition, forest structure, and their complex associations, which will favor precise conservation and management of forest resources in two region in the future.

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Seasonal Variability of SST Fronts in the Inner Sea of Chiloé and Its Adjacent Coastal Ocean, Northern Patagonia

Remote Sensing ◽

10.3390/rs13020181 ◽

2021 ◽

Vol 13 (2) ◽

pp. 181

Author(s):

Gonzalo S. Saldías ◽

Wilber Hernández ◽

Carlos Lara ◽

Richard Muñoz ◽

Cristian Rojas ◽

...

Keyword(s):

Coastal Upwelling ◽

Environmental Variability ◽

Function Analysis ◽

Coastal Ocean ◽

Dominant Mode ◽

Early Summer ◽

High Biological Activity ◽

Northern Patagonia ◽

Sst Gradient ◽

Sst Fronts

Surface oceanic fronts are regions characterized by high biological activity. Here, Sea Surface Temperature (SST) fronts are analyzed for the period 2003–2019 using the Multi-scale Ultra-high Resolution (MUR) SST product in northern Patagonia, a coastal region with high environmental variability through river discharges and coastal upwelling events. SST gradient magnitudes were maximum off Chiloé Island in summer and fall, coherent with the highest frontal probability in the coastal oceanic area, which would correspond to the formation of a coastal upwelling front in the meridional direction. Increased gradient magnitudes in the Inner Sea of Chiloé (ISC) were found primarily in spring and summer. The frontal probability analysis revealed the highest occurrences were confined to the northern area (north of Desertores Islands) and around the southern border of Boca del Guafo. An Empirical Orthogonal Function analysis was performed to clarify the dominant modes of variability in SST gradient magnitudes. The meridional coastal fronts explained the dominant mode (78% of the variance) off Chiloé Island, which dominates in summer, whereas the SST fronts inside the ISC (second mode; 15.8%) were found to dominate in spring and early summer (October–January). Future efforts are suggested focusing on high frontal probability areas to study the vertical structure and variability of the coastal fronts in the ISC and its adjacent coastal ocean.

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Volcanic and environmental impacts on subfossil chironomids from Northern Patagonia (Argentina) over the last 700 years

Limnology ◽

10.1007/s10201-021-00660-4 ◽

2021 ◽

Author(s):

M. Noel Serra ◽

Julieta Massaferro ◽

Gustavo Villarosa

Keyword(s):

Environmental Impacts ◽

Northern Patagonia ◽

Subfossil Chironomids

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Multiple-scale processes shape the population genetics of Tehuelche scallop, Aequipecten tehuelchus, in Northern Patagonia

Fisheries Research ◽

10.1016/j.fishres.2021.105971 ◽

2021 ◽

Vol 240 ◽

pp. 105971

Author(s):

Leandro Nicolás Getino Mamet ◽

Gaspar Soria ◽

Adrián Munguía Vega

Keyword(s):

Population Genetics ◽

Multiple Scale ◽

Northern Patagonia

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A New Furileusaurian Abelisaurid from La Invernada (Upper Cretaceous, Santonian, Bajo De La Carpa Formation), Northern Patagonia, Argentina

Journal of Vertebrate Paleontology ◽

10.1080/02724634.2020.1877151 ◽

2021 ◽

pp. e1877151

Author(s):

Federico A. Gianechini ◽

Ariel H. Méndez ◽

Leonardo S. Filippi ◽

Ariana Paulina-Carabajal ◽

Rubén D. Juárez-Valieri ◽

...

Keyword(s):

Upper Cretaceous ◽

Northern Patagonia

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Over half of western United States' most abundant tree species in decline

Nature Communications ◽

10.1038/s41467-020-20678-z ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Hunter Stanke ◽

Andrew O. Finley ◽

Grant M. Domke ◽

Aaron S. Weed ◽

David W. MacFarlane

Keyword(s):

United States ◽

Tree Species ◽

Tree Mortality ◽

Temperate Forests ◽

Size Structure ◽

Forest Disturbance ◽

Population Decline ◽

Western United States ◽

Scale Transformation ◽

Forest Composition

AbstractChanging forest disturbance regimes and climate are driving accelerated tree mortality across temperate forests. However, it remains unknown if elevated mortality has induced decline of tree populations and the ecological, economic, and social benefits they provide. Here, we develop a standardized forest demographic index and use it to quantify trends in tree population dynamics over the last two decades in the western United States. The rate and pattern of change we observe across species and tree size-distributions is alarming and often undesirable. We observe significant population decline in a majority of species examined, show decline was particularly severe, albeit size-dependent, among subalpine tree species, and provide evidence of widespread shifts in the size-structure of montane forests. Our findings offer a stark warning of changing forest composition and structure across the western US, and suggest that sustained anthropogenic and natural stress will likely result in broad-scale transformation of temperate forests globally.

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Corallimorpharians (Anthozoa: Corallimorpharia) from the Argentinean Sea

Zootaxa ◽

10.11646/zootaxa.4688.2.5 ◽

2019 ◽

Vol 4688 (2) ◽

pp. 249-263

Author(s):

DANIEL LAURETTA ◽

MARIANO I. MARTINEZ

Keyword(s):

Deep Sea ◽

Submarine Canyon ◽

Sister Group ◽

Southwestern Atlantic ◽

Sea Anemones ◽

Northern Patagonia ◽

Stony Corals ◽

Internal Morphology ◽

Southwestern Atlantic Ocean ◽

First Time

Corallimorpharians are a relative small group of anthozoan cnidarians, also known as jewel sea anemones. They resemble actiniarian sea anemones in lacking a skeleton and being solitary, but resemble scleractinian corals in external and internal morphology, and they are considered to be the sister group of the stony corals. Corynactis carnea (=Sphincteractis sanmatiensis) is a small, common and eye catching species that inhabits the shallow water of northern Patagonia and the Argentinean shelf up to 200 m depth. Corallimorphus rigidus is registered for the first time from the southwestern Atlantic Ocean. It is a rather big and rare species that inhabits only the deep sea. Only two specimens were found at 2934 m depth in Mar del Plata submarine canyon, in an area under the influence of the Malvinas current, which may explain its occurrence. These two species are the only two known jewel sea anemones in the Argentinean sea and are reported and described herein.

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