Assessing the Sensitivity of Riparian Algarrobo Dulce (Prosopis flexuosa DC) Radial Growth to Hydrological Changes

Abstract Ecotones, as for example riparian zones, have long interested ecologists, due to their potential role in generating species biodiversity and evolutionary novelty, as well as their sensitivity to environmental changes. Along riparian areas, vegetation is recognized for its ecological importance in several ecosystemic processes. In the Central Monte Desert (central-west Argentina), Prosopis flexuosa grows in territories characterized by a permanent access to water reservoirs, e.g. along riverbanks, where the species forms the classic gallery forests. Despite the ecosystemic role of the different Prosopis species distributed in arid lands, thus far no analysis has been conducted regarding the relation between their radial growth and hydrological changes, namely streamflow variability, in riparian settings. To fill this gap of knowledge, we performed a dendrochronological analysis considering several riparian P. flexuosa trees differing in their spatial position in relation to the riverbank. Pointer years, correlation function, and regression analyses show differences in the dendrohydrological signal of the studied species, probably function of tree distance from the river. In this sense, radial growth of trees distributed near the riverbank is tightly coupled to spring-summer (September to March) stream-flow variability, whereas for farthest trees the ring development is driven by a combination of winter and spring river discharge and late-summer precipitation amount. The presented results demonstrate the potentiality of P. flexuosa, and in a broader sense of the Prosopis genus, in dendrohydrological studies.

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Influences of climate on the radial growth of lodgepole pine in Alberta

Botany ◽

10.1139/b07-120 ◽

2008 ◽

Vol 86 (2) ◽

pp. 167-178 ◽

Cited By ~ 17

Author(s):

Sophan Chhin ◽

E.H. (Ted) Hogg ◽

Victor J. Lieffers ◽

Shongming Huang

Keyword(s):

Radial Growth ◽

Climatic Factors ◽

Lodgepole Pine ◽

Regional Growth ◽

Regional Scale ◽

Summer Precipitation ◽

Late Summer ◽

Moisture Stress ◽

Late Winter ◽

Spring Precipitation

We examined a network of 17 lodgepole pine ( Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) sites in Alberta in the cordilleran forests along the eastern slopes of the Rocky Mountains and in western Cypress Hills, using a dendrochronological approach to identify the principal climatic factors that have influenced the historical, regional-scale pattern of radial growth of lodgepole pine. Correlation and regression analysis of the regional growth–climate relationships showed that radial growth was negatively associated with late-summer temperatures, and positively related to the late-summer precipitation totals from the previous growth season. Radial growth also responded positively to winter and spring temperatures, and was negatively related to late winter–early spring precipitation. The results suggested that the lag in response to heat and moisture stress, cold and snowy winters, and the length of the current growing season are important determinants of the radial growth of lodgepole pine in Alberta.

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Roles of anthropogenic forcings in the observed trend of decreasing late-summer precipitation over the East Asian transitional climate zone

Scientific Reports ◽

10.1038/s41598-021-84470-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Wei Zhao ◽

Wen Chen ◽

Shangfeng Chen ◽

Hainan Gong ◽

Tianjiao Ma

Keyword(s):

Asian Summer Monsoon ◽

Dominant Role ◽

East Asian ◽

Eastern China ◽

Summer Precipitation ◽

Late Summer ◽

Water Vapor Transport ◽

Anthropogenic Aerosol ◽

Climate Zone ◽

Drying Trend

AbstractObservations indicate that late-summer precipitation over the East Asian transitional climate zone (TCZ) showed a pronounced decreasing trend during 1951–2005. This study examines the relative contributions of anthropogenic [including anthropogenic aerosol (AA) and greenhouse gas (GHG)] and natural forcings to the drying trend of the East Asian TCZ based on simulations from CMIP5. The results indicate that AA forcing plays a dominant role in contributing to the drying trend of the TCZ. AA forcing weakens the East Asian summer monsoon via reducing the land-sea thermal contrast, which induces strong low-level northerly anomalies over eastern China, suppresses water vapor transport from southern oceans and results in drier conditions over the TCZ. In contrast, GHG forcing leads to a wetting trend in the TCZ by inducing southerly wind anomalies, thereby offsetting the effect of the AA forcing. Natural forcing has a weak impact on the drying trend of the TCZ due to the weak response of atmospheric anomalies.

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A Stable Isotope Approach for Estimating the Contribution of Recycled Moisture to Precipitation in Lanzhou City, China

Water ◽

10.3390/w13131783 ◽

2021 ◽

Vol 13 (13) ◽

pp. 1783

Author(s):

Fenli Chen ◽

Mingjun Zhang ◽

Xixi Wu ◽

Shengjie Wang ◽

Athanassios A. Argiriou ◽

...

Keyword(s):

Environmental Changes ◽

Water Cycle ◽

Summer Precipitation ◽

Northwest China ◽

Plant Transpiration ◽

Surface Evaporation ◽

Lanzhou City ◽

Water Vapors ◽

Spatial Differences ◽

Dependent Parameter

The proportional contribution of recycled moisture to local precipitation is a geographically dependent parameter that cannot be ignored in water budgets. Stable hydrogen and oxygen isotopes are sensitive to environmental changes and can be applied to investigate the modern water cycle. In this study, a three-component mixing model is used to calculate the contribution of different water vapors (advection, evaporation and transpiration) to summer precipitation in Lanzhou city, Northwest China. The results show that for all sampling sites in Lanzhou, the contribution of advection vapor to precipitation is the largest, followed by the plant transpiration vapor, and the contribution of surface evaporation water vapor is usually the least, with the average values of 87.96%, 9.1% and 2.9%, respectively. The spatial differences of plant transpiration vapor are generally larger than those of advection vapor and surface evaporation vapor, and the high values appear in Yongdeng, Daheng and Gaolan.

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Atmospheric Thermal and Dynamic Vertical Structures of Summer Hourly Precipitation in Jiulong of the Tibetan Plateau

Atmosphere ◽

10.3390/atmos12040505 ◽

2021 ◽

Vol 12 (4) ◽

pp. 505

Author(s):

Yonglan Tang ◽

Guirong Xu ◽

Rong Wan ◽

Xiaofang Wang ◽

Junchao Wang ◽

...

Keyword(s):

Wind Speed ◽

Tibetan Plateau ◽

Precipitation Amount ◽

Summer Precipitation ◽

The Tibetan Plateau ◽

Hourly Precipitation ◽

Air Convection ◽

Precipitation Variation ◽

Long Term Observation

It is an important to study atmospheric thermal and dynamic vertical structures over the Tibetan Plateau (TP) and their impact on precipitation by using long-term observation at representative stations. This study exhibits the observational facts of summer precipitation variation on subdiurnal scale and its atmospheric thermal and dynamic vertical structures over the TP with hourly precipitation and intensive soundings in Jiulong during 2013–2020. It is found that precipitation amount and frequency are low in the daytime and high in the nighttime, and hourly precipitation greater than 1 mm mostly occurs at nighttime. Weak precipitation during the daytime may be caused by air advection, and strong precipitation at nighttime may be closely related with air convection. Both humidity and wind speed profiles show obvious fluctuation when precipitation occurs, and the greater the precipitation intensity, the larger the fluctuation. Moreover, the fluctuation of wind speed is small in the morning, large at noon and largest at night, presenting a similar diurnal cycle to that of convective activity over the TP, which is conductive to nighttime precipitation. Additionally, the inverse layer is accompanied by the inverse humidity layer, and wind speed presents multi-peaks distribution in its vertical structure. Both of these are closely related with the underlying surface and topography of Jiulong. More studies on physical mechanism and numerical simulation are necessary for better understanding the atmospheric phenomenon over the TP.

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Radial Growth Decline of White Spruce (Picea glauca) During Hot Summers without Drought: Preliminary Results from a Study Site South of a Boreal Forest Border

Canadian Journal of Forest Research ◽

10.1139/cjfr-2021-0268 ◽

2022 ◽

Author(s):

Andrei Lapenis ◽

George Robinson ◽

Gregory B. Lawrence

Keyword(s):

New York ◽

Boreal Forest ◽

Picea Glauca ◽

Radial Growth ◽

Summer Precipitation ◽

White Spruce ◽

Southern Limit ◽

Central New York ◽

Growth Decline ◽

Hot Days

Here we investigate the possible<sup></sup> future response of white spruce (Picea glauca) to a warmer climate by studying trees planted 90 years ago near the southern limit of their climate tolerance in central New York, 300 km south of the boreal forest where this species is prevalent. We employed high-frequency recording dendrometers to determine radial growth phenology of six mature white spruce trees during 2013-2017. Results demonstrate significant reductions in the length of radial growth periods inversely proportional to the number of hot days with air temperature exceeding 30 oC. During years with very hot summers, the start of radial growth began about 3 days earlier than the 2013-2017 average. However, in those same years the end of radial growth was also about 17 days earlier resulting in a shorter (70 versus 100 day), radial growth season. Abundant (350-500 mm) summer precipitation, which resulted in soil moisture values of 20-30% allowed us to dismiss drought as a factor. Instead, a likely cause of reduced radial growth was mean temperature that exceeded daily average of 30<sup> o</sup>C that lead to photoinhibition.

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Detectable Anthropogenic Influence on Changes in Summer Precipitation in China

Journal of Climate ◽

10.1175/jcli-d-19-0285.1 ◽

2020 ◽

Vol 33 (13) ◽

pp. 5357-5369

Author(s):

Chunhui Lu ◽

Fraser C. Lott ◽

Ying Sun ◽

Peter A. Stott ◽

Nikolaos Christidis

Keyword(s):

Human Life ◽

Eastern China ◽

Precipitation Amount ◽

Summer Precipitation ◽

Heavy Precipitation ◽

Observation Data ◽

Anthropogenic Influence ◽

Anthropogenic Forcing ◽

The Future ◽

Light Precipitation

AbstractIn China, summer precipitation contributes a major part of the total precipitation amount in a year and has major impacts on society and human life. Whether any changes in summer precipitation are affected by external forcing on the climate system is an important issue. In this study, an optimal fingerprinting method was used to compare the observed changes of total, heavy, moderate, and light precipitation in summer derived from newly homogenized observation data with the simulations from multiple climate models participating in phase 5 of the Coupled Model Intercomparison Project (CMIP5). The results demonstrate that the anthropogenic forcing signal can be detected and separated from the natural forcing signal in the observed increase of seasonal accumulated precipitation amount for heavy precipitation in summer in China and eastern China (EC). The simulated changes in heavy precipitation are generally consistent with observed change in China but are underestimated in EC. When the changes in precipitation of different intensities are considered simultaneously, the human influence on simultaneous changes in moderate and light precipitation can be detected in China and EC in summer. Changes attributable to anthropogenic forcing explain most of the observed regional changes for all categories of summer precipitation, and natural forcing contributes little. In the future, with increasing anthropogenic influence, the attribution-constrained projection suggests that heavy precipitation in summer will increase more than that from the model raw outputs. Society may therefore face a higher risk of heavy precipitation in the future.

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Spatial and temporal variation in abundance, group size and behaviour of bottlenose dolphins in the Florida coastal Everglades

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s002531541700090x ◽

2017 ◽

Vol 98 (5) ◽

pp. 1097-1107 ◽

Cited By ~ 2

Author(s):

Robin E. Sarabia ◽

Michael R. Heithaus ◽

Jeremy J. Kiszka

Keyword(s):

Temporal Variation ◽

Environmental Changes ◽

Bottlenose Dolphins ◽

Ecosystem Restoration ◽

Spatial And Temporal Variation ◽

Coastal Oceans ◽

Inland Bays ◽

Long Time ◽

Time Periods ◽

Ecological Importance

Bottlenose dolphins (Tursiops truncatus) are abundant in many coastal ecosystems, including the coastal Everglades. Understanding spatial and temporal variation in their abundance and group sizes is important for estimating their potential ecological importance and predicting how environmental changes (e.g. ecosystem restoration) might impact their populations. From August 2010 to June 2012, we completed a total of 67 belt transects covering a total of 2650 linear km and an area of 1232 km2. Dolphin densities varied spatially and temporally. The highest densities of dolphins were found in coastal oceans and inland bays and were lowest in rivers. Use of rivers, however, increased during the dry season while densities in other habitats remained similar across seasons. Dolphins appeared to prefer portions of bays close to mangrove-covered islands over open waters. A resighting rate of 63.6% of individuals across the 2-year study suggests that at least a portion of the population is probably resident within study regions over long time periods. The largest groups (mean 6.28, range 1–31) were found in open waters and bays despite apparently low predation pressure. Indeed, shark bite scars – likely the result of unsuccessful predation attempts – were conclusively observed on only 1% of individuals. Although further studies are warranted, the high densities of dolphins suggest that they are an important upper trophic level predator in the coastal Everglades, but their ecological importance probably varies in space and time.

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Importance of Algarrobo Trees Prosopis flexuosa for Territory Establishment of Three Seed-Eating Passerine Species in the Central Monte Desert

Ardea ◽

10.5253/arde.v109i3.a6 ◽

2021 ◽

Vol 109 (2) ◽

Author(s):

M. Cecilia Sagario ◽

Víctor R. Cueto

Keyword(s):

Monte Desert ◽

Passerine Species ◽

Seed Eating ◽

Prosopis Flexuosa

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Revisiting extreme precipitation amounts over southern South America and implications for the Patagonian Icefields

Hydrology and Earth System Sciences ◽

10.5194/hess-24-2003-2020 ◽

2020 ◽

Vol 24 (4) ◽

pp. 2003-2016 ◽

Cited By ~ 3

Author(s):

Tobias Sauter

Keyword(s):

Sea Level ◽

Environmental Changes ◽

Net Primary Production ◽

Precipitation Amount ◽

Moisture Flux ◽

Polar Regions ◽

Surface Mass ◽

Precipitation Estimates ◽

Modelling Studies ◽

New Perspective

Abstract. Patagonia is thought to be one of the wettest regions on Earth, although available regional precipitation estimates vary considerably. This uncertainty complicates understanding and quantifying the observed environmental changes, such as glacier recession, biodiversity decline in fjord ecosystems and enhanced net primary production. The Patagonian Icefields, for example, are one of the largest contributors to sea-level rise outside the polar regions, and robust hydroclimatic projections are needed to understand and quantify current and future mass changes. The reported projections of precipitation from numerical modelling studies tend to overestimate those from in situ determinations, and the plausibility of these numbers has never been carefully scrutinized, despite the significance of this topic to our understanding of observed environmental changes. Here I use simple physical arguments and a linear model to test the plausibility of the current precipitation estimates and its impact on the Patagonian Icefields. The results show that environmental conditions required to sustain a mean precipitation amount exceeding 6.09±0.64 m yr−1 are untenable according to the regional moisture flux. The revised precipitation values imply a significant reduction in the surface mass balance of the Patagonian Icefields compared to previously reported values. This yields a new perspective on the response of Patagonia's glaciers to climate change and their sea-level contribution and might also help reduce uncertainties in the change of other precipitation-driven environmental phenomena.

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