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Bas TG, Sáez ML, Sáez N. Sustainable Development versus Extractivist Deforestation in Tropical, Subtropical, and Boreal Forest Ecosystems: Repercussions and Controversies about the Mother Tree and the Mycorrhizal Network Hypothesis. PLANTS (BASEL, SWITZERLAND) 2024; 13:1231. [PMID: 38732447 PMCID: PMC11085170 DOI: 10.3390/plants13091231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Revised: 04/23/2024] [Accepted: 04/28/2024] [Indexed: 05/13/2024]
Abstract
This research reviews the phenomenon of extractive deforestation as a possible trigger for cascade reactions that could affect part of the forest ecosystem and its biodiversity (surface, aerial, and underground) in tropical, subtropical, and boreal forests. The controversy and disparities in criteria generated in the international scientific community around the hypothesis of a possible link between "mother trees" and mycorrhizal networks in coopetition for nutrients, nitrogen, and carbon are analyzed. The objective is to promote awareness to generate more scientific knowledge about the eventual impacts of forest extraction. Public policies are emphasized as crucial mediators for balanced sustainable development. Currently, the effects of extractive deforestation on forest ecosystems are poorly understood, which requires caution and forest protection. Continued research to increase our knowledge in molecular biology is advocated to understand the adaptation of biological organisms to the new conditions of the ecosystem both in the face of extractive deforestation and reforestation. The environmental impacts of extractive deforestation, such as the loss of biodiversity, soil degradation, altered water cycles, and the contribution of climate change, remain largely unknown. Long-term and high-quality research is essential to ensure forest sustainability and the preservation of biodiversity for future generations.
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Affiliation(s)
- Tomas Gabriel Bas
- Escuela de Ciencias Empresariales, Universidad Católica del Norte, Coquimbo 1780000, Chile;
| | - Mario Luis Sáez
- Facultad de Humanidades, La Serena University, Coquimbo 1700000, Chile;
| | - Nicolas Sáez
- Escuela de Ciencias Empresariales, Universidad Católica del Norte, Coquimbo 1780000, Chile;
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2
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Costa PODA, Júnior IF, Paes ET, Ribeiro FCP, Silva JADA, Santos DCD, Cintra IHA. Proposal for the zoning of the industrial Brachyplatystoma vaillantii fisheries of the North Coast of Brazil and the influence of climatic factors on the fluctuations in the abundance of the species. AN ACAD BRAS CIENC 2021; 94:e20191320. [PMID: 34787289 DOI: 10.1590/0001-3765202120191320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Accepted: 02/02/2021] [Indexed: 11/21/2022] Open
Abstract
The present study was based on the analysis of 10,467 trawls of the industrial piramutaba (Brachyplatystoma vaillantii) fishing fleet of the Brazilian state of Pará, which were mapped by onboard GPS loggers (between February 2008 and September 2011) and the PREPS data from 40 vessels which were tracked by this system between 2008 and 2011. The variation in the mean monthly CPUE, based on Lomb's periodogram, revealed a well-defined and constant cycle with a duration of approximately one year. Three environmental factors influenced this cycle. The El Niño 3.4 index had a negative correlation with the CPUE of the piramutaba fishery, with a time lag of 15 months, while monthly rainfall and the mean discharge of the Amazon River correlated strongly (r=0.89 and 0.87, respectively; p<0.001) with the CPUE, with time lags of 12 and 11 months, respectively. The spatiotemporal analysis of the distribution of the activity of the piramutaba fishing fleet indicated that the most intense area of operation of the fleet lies between latitudes 00º N and 02° N, and longitudes 047º40' W and 049º40' W. This area was divided into four geographic quadrants, although fishery operations were concentrated in only three of these quadrants. The study proposed a quadrimester fishing cycle with zoning in three of the quadrants, where fishing would be permitted for four months (occupation period), followed by an 8-month rest period for the recuperation of stocks, aiming at the sustainability of this fishing exploration.
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Affiliation(s)
- Pamella O DA Costa
- Universidade Federal Rural da Amazônia, Avenida Presidente Tancredo Neves, 2501, 66077-830 Belém, PA, Brazil
| | - Ivan F Júnior
- Universidade Federal Rural da Amazônia, Instituto Socioambiental e dos Recursos Hídricos, Avenida Presidente Tancredo Neves, 2501, 66077-830 Belém, PA, Brazil.,Universidade Federal Rural da Amazônia, Laboratório de Prospecção e Estatística Pesqueira, Avenida Presidente Tancredo Neves, 2501, 66077-830 Belém, PA, Brazil
| | - Eduardo T Paes
- Universidade Federal Rural da Amazônia, Instituto Socioambiental e dos Recursos Hídricos, Avenida Presidente Tancredo Neves, 2501, 66077-830 Belém, PA, Brazil
| | - Fábio C P Ribeiro
- Universidade Federal Rural da Amazônia, Instituto Socioambiental e dos Recursos Hídricos, Avenida Presidente Tancredo Neves, 2501, 66077-830 Belém, PA, Brazil
| | - Jéssica A DA Silva
- Universidade Federal Rural da Amazônia, Avenida Presidente Tancredo Neves, 2501, 66077-830 Belém, PA, Brazil
| | - Deusilene C Dos Santos
- Universidade Federal Rural da Amazônia, Avenida Presidente Tancredo Neves, 2501, 66077-830 Belém, PA, Brazil
| | - Israel H A Cintra
- Universidade Federal Rural da Amazônia, Instituto Socioambiental e dos Recursos Hídricos, Avenida Presidente Tancredo Neves, 2501, 66077-830 Belém, PA, Brazil
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Badraghi A, Ventura M, Polo A, Borruso L, Giammarchi F, Montagnani L. Soil respiration variation along an altitudinal gradient in the Italian Alps: Disentangling forest structure and temperature effects. PLoS One 2021; 16:e0247893. [PMID: 34403412 PMCID: PMC8370607 DOI: 10.1371/journal.pone.0247893] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 07/22/2021] [Indexed: 11/19/2022] Open
Abstract
On the mountains, along an elevation gradient, we generally observe an ample variation in temperature, with the associated difference in vegetation structure and composition and soil properties. With the aim of quantifying the relative importance of temperature, vegetation and edaphic properties on soil respiration (SR), we investigated changes in SR along an elevation gradient (404 to 2101 m a.s.l) in the southern slopes of the Alps in Northern Italy. We also analysed soil physicochemical properties, including soil organic carbon (SOC) and nitrogen (N) stocks, fine root C and N, litter C and N, soil bulk densities and soil pH at five forest sites, and also stand structural properties, including vegetation height, age and basal area. Our results indicated that SR rates increased with temperature in all sites, and 55–76% of SR variability was explained by temperature. Annual cumulative SR, ranging between 0.65–1.40 kg C m-2 yr-1, decreased along the elevation gradient, while temperature sensitivity (Q10) of SR increased with elevation. However, a high SR rate (1.27 kg C m-2 yr-1) and low Q10 were recorded in the mature conifer forest stand at 1731 m a.s.l., characterized by an uneven-aged structure and high dominant tree height, resulting in a nonlinear relationship between elevation and temperature. Reference SR at 10°C (SRref) was unrelated to elevation, but was related to tree height. A significant negative linear relationship was found between bulk density and elevation. Conversely, SOC, root C and N stock, pH, and litter mass were best fitted by nonlinear relationships with elevation. However, these parameters were not significantly correlated with SR when the effect of temperature was removed (SRref). These results demonstrate that the main factor affecting SR in forest ecosystems along this Alpine elevation gradient is temperature, but its regulating role can be strongly influenced by site biological characteristics, particularly vegetation type and structure, affecting litter quality and microclimate. This study also confirms that high elevation sites are rich in SOC and more sensitive to climate change, being prone to high C losses as CO2. Furthermore, our data indicate a positive relationship between Q10 and dominant tree height, suggesting that mature forest ecosystems characterized by an uneven-age structure, high SRref and moderate Q10, may be more resilient.
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Affiliation(s)
- Aysan Badraghi
- Faculty of Science and Technology, Free University of Bozen-Bolzano, Bolzano, Italy
| | - Maurizio Ventura
- Faculty of Science and Technology, Free University of Bozen-Bolzano, Bolzano, Italy
| | - Andrea Polo
- Faculty of Science and Technology, Free University of Bozen-Bolzano, Bolzano, Italy
| | - Luigimaria Borruso
- Faculty of Science and Technology, Free University of Bozen-Bolzano, Bolzano, Italy
| | - Francesco Giammarchi
- Faculty of Science and Technology, Free University of Bozen-Bolzano, Bolzano, Italy
| | - Leonardo Montagnani
- Faculty of Science and Technology, Free University of Bozen-Bolzano, Bolzano, Italy
- Forest Services, Autonomous Province of Bolzano, Bolzano, Italy
- * E-mail:
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Giroux A, Ortega Z, Bertassoni A, Desbiez ALJ, Kluyber D, Massocato GF, DE Miranda G, Mourão G, Surita L, Attias N, Bianchi RDC, Gasparotto VPDO, Oliveira-Santos LGR. The role of environmental temperature on movement patterns of giant anteaters. Integr Zool 2021; 17:285-296. [PMID: 33738919 DOI: 10.1111/1749-4877.12539] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Mammals can show conspicuous behavioral responses to thermal variation, including changes in movement patterns. We used an integrative approach to understand how environmental temperature can drive the movement behavior of a mammal with low capacity for physiological thermoregulation, the giant anteater (Myrmecophaga tridactyla). We tracked 52 giant anteaters in 7 areas throughout the Brazilian savannah. We estimated the distance moved, area used, use of forest areas, and mean environmental temperature for each monitoring day of each individual. We modeled these data with Mixed Structural Equations - considering the possible interactions between our variables and controlling for sex and body mass. Giant anteaters reduced displacement and increased forest use with decreasing environmental temperature, probably because of their low body heat production. It is possible that they reduce distance moved and area used by reducing the duration of activity. With decreasing temperature, forest habitats become warmer than open ones, besides buffer rain and chilly winds. Reducing displacement and using forests are important strategies to reduce body heat loss and the energetic costs of thermoregulation. However, decreasing movement can limit food access and, consequently, fitness. Therefore, we highlight the importance of forests as thermal shelters. With increasing frequency and intensity of extreme weather events, we showed the need to preserve forest patches to offer suitable conditions for tropical mammals' behavioral thermoregulation. In this context, policies favoring deforestation on Brazilian territory are especially worrisome. Finally, we emphasize the need of integrative approaches to understand the complex interactions between organisms and the environment.
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Affiliation(s)
- Aline Giroux
- Ecology Department, Federal University of Mato Grosso do Sul (UFMS), Campo Grande, Mato Grosso do Sul, Brazil
| | - Zaida Ortega
- Ecology Department, Federal University of Mato Grosso do Sul (UFMS), Campo Grande, Mato Grosso do Sul, Brazil
| | - Alessandra Bertassoni
- Post Graduate Program of Ecology and Evolution, Federal University of Goiás (UFG), Goiânia, Goiás, Brazil.,Institute of Research and Conservation of Anteaters in Brazil (PROJETO TAMANDUÁ), Parnaíba, Piauí, Brazil
| | - Arnaud Léonard Jean Desbiez
- Institute for the Conservation of Wild Animals (ICAS), Campo Grande, Mato Grosso do Sul, Brazil.,Royal Zoological Society of Scotland (RZSS), Murrayfield, Edinburgh, UK.,Institute for Ecological Research (IPÊ), Nazaré Paulista, São Paulo, Brazil
| | - Danilo Kluyber
- Institute for the Conservation of Wild Animals (ICAS), Campo Grande, Mato Grosso do Sul, Brazil.,Institute for Ecological Research (IPÊ), Nazaré Paulista, São Paulo, Brazil.,Naples Zoo at Caribbean Gardens, Naples, Florida, USA
| | - Gabriel Favero Massocato
- Institute for the Conservation of Wild Animals (ICAS), Campo Grande, Mato Grosso do Sul, Brazil.,Institute for Ecological Research (IPÊ), Nazaré Paulista, São Paulo, Brazil.,The Houston Zoo, Houston, Texas, USA
| | | | | | - Luciana Surita
- Natural Resources Graduate Program (PRONAT) - Federal University of Roraima (UFRR), Boa Vista, Roraima, Brazil
| | - Nina Attias
- Institute for the Conservation of Wild Animals (ICAS), Campo Grande, Mato Grosso do Sul, Brazil.,Animal Biology Graduate Program, Federal University of Mato Grosso do Sul (UFMS), Campo Grande, Mato Grosso do Sul, Brazil
| | - Rita de Cassia Bianchi
- Animal Biology Department, São Paulo State University (UNESP), São José do Rio Preto, São Paulo, Brazil
| | - Vinícius Peron de Oliveira Gasparotto
- Institute of Research and Conservation of Anteaters in Brazil (PROJETO TAMANDUÁ), Parnaíba, Piauí, Brazil.,Department of Preventive Veterinary Medicine and Animal Health, School of Veterinary Medicine, University of São Paulo (USP), São Paulo, SP, Brazil.,Brazilian Institute for Conservation Medicine (TRÍADE), Recife, Pernambuco, Brazil
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Remotely sensed thermal decay rate: an index for vegetation monitoring. Sci Rep 2020; 10:9812. [PMID: 32555210 PMCID: PMC7299984 DOI: 10.1038/s41598-020-66193-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 05/08/2020] [Indexed: 11/08/2022] Open
Abstract
Vegetation buffers local diurnal land surface temperatures, however, this effect has found limited applications for remote vegetation characterization. In this work, we parameterize diurnal temperature variations as the thermal decay rate derived by using satellite daytime and nighttime land surface temperatures and modeled using Newton's law of cooling. The relationship between the thermal decay rate and vegetation depends on many factors including vegetation type, size, water content, location, and local conditions. The theoretical relationships are elucidated, and empirical relationships are presented. Results show that the decay rate summarizes both vegetation structure and function and exhibits a high correlation with other established vegetation-related observations. As proof of concept, we interpret 15-year spatially explicit trends in the annual thermal decay rates over Africa and discuss results. Given recent increases in availability of finer spatial resolution satellite thermal measurements, the thermal decay rate may be a useful index for monitoring vegetation.
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Kovács B, Tinya F, Németh C, Ódor P. Unfolding the effects of different forestry treatments on microclimate in oak forests: results of a 4-yr experiment. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2020; 30:e02043. [PMID: 31758609 PMCID: PMC7900960 DOI: 10.1002/eap.2043] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 09/23/2019] [Accepted: 10/21/2019] [Indexed: 05/11/2023]
Abstract
A stable below-canopy microclimate of forests is essential for their biodiversity and ecosystem functionality. Forest management necessarily modifies the buffering capacity of woodlands. However, the specific effects of different forestry treatments on site conditions, the temporal recovery after the harvests, and the reason for the contrasts between treatments are still poorly understood. The effects of four different forestry treatments (clear-cutting, retention tree group, preparation cutting, and gap-cutting) on microclimatic variables were studied within a field experiment in a managed oak-dominated stand in Hungary, before (2014) and after (2015-2017) the interventions by complete block design with six replicates. From the first post-treatment year, clear-cuts differed the most from the uncut control due to the increased irradiance and heat load. Means and variability of air and soil temperature increased, air became dryer along with higher soil moisture levels. Retention tree groups could effectively ameliorate the extreme temperatures but not the mean values. Preparation cutting induced slight changes from the original buffered and humid forest microclimate. Despite the substantially more incoming light, gap-cutting could retain the cool and humid air conditions and showed the highest increase in soil moisture after the interventions. For most microclimate variables, we could not observe any obvious trend within 3 yr. However, soil temperature variability decreased with time in clear-cuts, while soil moisture difference continuously increased in gap- and clear-cuts. Based on multivariate analyses, the treatments separated significantly based mainly on the temperature maxima and variability. We found that (1) the effect sizes among treatment levels were consistent throughout the years, (2) the climatic recovery time for variables appears to be far more than 3 yr, and (3) the applied silvicultural methods diverged mainly among the temperature maxima. Based on our study, the spatially heterogeneous and fine-scaled treatments of continuous cover forestry (gap-cutting, selection systems) are recommended. By applying these practices, the essential structural elements creating buffered microclimate could be more successfully maintained. Thus, forestry interventions could induce less pronounced alterations in environmental conditions for forest-dwelling organism groups.
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Affiliation(s)
- Bence Kovács
- MTA Centre for Ecological ResearchInstitute of Ecology and BotanyAlkotmány út 2‐4VácrátótH‐2163Hungary
- MTA Centre for Ecological ResearchGINOP Sustainable Ecosystems Research GroupKlebelsberg Kuno utca 3TihanyH‐8237Hungary
- Department of Plant Systematics, Ecology and Theoretical BiologyEötvös Loránd UniversityPázmány Péter sétány 1/CBudapestH‐1117Hungary
| | - Flóra Tinya
- MTA Centre for Ecological ResearchInstitute of Ecology and BotanyAlkotmány út 2‐4VácrátótH‐2163Hungary
| | - Csaba Németh
- MTA Centre for Ecological ResearchGINOP Sustainable Ecosystems Research GroupKlebelsberg Kuno utca 3TihanyH‐8237Hungary
| | - Péter Ódor
- MTA Centre for Ecological ResearchInstitute of Ecology and BotanyAlkotmány út 2‐4VácrátótH‐2163Hungary
- MTA Centre for Ecological ResearchGINOP Sustainable Ecosystems Research GroupKlebelsberg Kuno utca 3TihanyH‐8237Hungary
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Moura MM, Dos Santos AR, Pezzopane JEM, Alexandre RS, da Silva SF, Pimentel SM, de Andrade MSS, Silva FGR, Branco ERF, Moreira TR, da Silva RG, de Carvalho JR. Relation of El Niño and La Niña phenomena to precipitation, evapotranspiration and temperature in the Amazon basin. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 651:1639-1651. [PMID: 30360289 DOI: 10.1016/j.scitotenv.2018.09.242] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 08/28/2018] [Accepted: 09/18/2018] [Indexed: 05/18/2023]
Abstract
Weather phenomena El Niño and La Niña are observed by meteorological variables, which allows you to track climate change and its possible effects in certain regions. The objective of this study was to analyze the behavior of rainfall, temperature and evapotranspiration in the Amazon river basin (Latitudes 5° N to 20° S and Longitudes 50° W to 80° W), comparing them with the occurrence of El Niño and La Niña phenomena, from January 2000 to December 2016. The values referring to the meteorological variables were obtained from the TRMM and MODIS orbital sensors. After data pre-processing, the data were separated into monthly and annual scales and per period according to the presence or absence of El Niño and La Niña phenomena. Based on the results obtained, it was observed that the studied variables were affected by modification of both phenomena. The modifications are more noticeable in the distinction between the more and less rainy periods. Among the variables studied, the evapotranspiration was severely affected in the rainiest months, the La Niña phenomenon, and the least rainy months, El Niño. Thus, it was possible to conclude that, in general, the presence of La Niña increased precipitation values in comparison to the Neutral period, but the inverse occurs in the presence of El Niño. The methodology applied in the present study was adequate for the analysis of the modifications of the meteorological variables coming from the El Niño and La Niña phenomena, being able to be adapted to other variables and regions.
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Affiliation(s)
- Marks Melo Moura
- Federal University of Espírito Santo/UFES, Center of Agricultural Sciences and Engineering, Alto Universitário, s/n 29500-000 Alegre, ES, Brazil
| | - Alexandre Rosa Dos Santos
- Federal University of Espírito Santo/UFES, Center of Agricultural Sciences and Engineering, Alto Universitário, s/n 29500-000 Alegre, ES, Brazil.
| | - José Eduardo Macedo Pezzopane
- Federal University of Espírito Santo/UFES, Center of Agricultural Sciences and Engineering, Alto Universitário, s/n 29500-000 Alegre, ES, Brazil
| | - Rodrigo Sobreira Alexandre
- Federal University of Espírito Santo/UFES, Center of Agricultural Sciences and Engineering, Alto Universitário, s/n 29500-000 Alegre, ES, Brazil
| | - Samuel Ferreira da Silva
- Federal University of Espírito Santo/UFES, Center of Agricultural Sciences and Engineering, Alto Universitário, s/n 29500-000 Alegre, ES, Brazil
| | - Stefania Marques Pimentel
- Federal University of Espírito Santo/UFES, Center of Agricultural Sciences and Engineering, Alto Universitário, s/n 29500-000 Alegre, ES, Brazil
| | - Maria Sueliane Santos de Andrade
- Federal University of Espírito Santo/UFES, Center of Agricultural Sciences and Engineering, Alto Universitário, s/n 29500-000 Alegre, ES, Brazil
| | - Felipe Gimenes Rodrigues Silva
- Federal University of Espírito Santo/UFES, Center of Agricultural Sciences and Engineering, Alto Universitário, s/n 29500-000 Alegre, ES, Brazil
| | - Elvis Ricardo Figueira Branco
- Federal University of Espírito Santo/UFES, Center of Agricultural Sciences and Engineering, Alto Universitário, s/n 29500-000 Alegre, ES, Brazil
| | - Taís Rizzo Moreira
- Federal University of Espírito Santo/UFES, Center of Agricultural Sciences and Engineering, Alto Universitário, s/n 29500-000 Alegre, ES, Brazil
| | - Rosane Gomes da Silva
- Federal University of Espírito Santo/UFES, Center of Agricultural Sciences and Engineering, Alto Universitário, s/n 29500-000 Alegre, ES, Brazil
| | - José Romário de Carvalho
- Federal University of Espírito Santo/UFES, Center of Agricultural Sciences and Engineering, Alto Universitário, s/n 29500-000 Alegre, ES, Brazil
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The Short-Term Effects of Experimental Forestry Treatments on Site Conditions in an Oak–Hornbeam Forest. FORESTS 2018. [DOI: 10.3390/f9070406] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Qu L, Chen J, Dong G, Shao C. Heavy mowing enhances the effects of heat waves on grassland carbon and water fluxes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 627:561-570. [PMID: 29426179 DOI: 10.1016/j.scitotenv.2018.01.287] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 01/21/2018] [Accepted: 01/29/2018] [Indexed: 06/08/2023]
Abstract
Heat waves (HWs) are a type of extreme weather event that is of growing concern in the scientific community. Yet field data based on sound experiment on the variation of ecosystem CO2 levels under HWs remain rare. Additionally, ecosystems react to HWs and the coupled human activities (such as grazing in grasslands) are unknown. Thus, a 3-year field experiment was conducted to simulate HWs in conjunction with different mowing intensities that mimicking grazing in a Stipa krylovii steppe on the Mongolian Plateau. HWs significantly decreased ecosystem exchange (NEE) of CO2, ecosystem respiration (Re) and gross ecosystem productivity (GEP) by 31%, 5% and 16%, respectively, over the three years. Continuous HWs over multiple years produced cumulative effects by reducing NEE at 20%, 34% and 40% in the first, second and third HW years, respectively. During three pre-defined three periods of HWs (during HW period, after HW period in the same year, and after HW period in the next year), variations in water use efficiency indicated that the grassland ecosystem exhibited a strategy for adapting to the continuous HWs to a certain extent, by adjusting community structure or increasing litter biomass. Finally, mowing increased the effects of HWs by extending the legacy effect, such that restoration of the grassland required a greater amount of time under the combination of HWs and mowing.
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Affiliation(s)
- Luping Qu
- Forest Ecology Stable Isotope Center, Forestry College, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Jiquan Chen
- Center for Global Changes and Earth Observation/Department of Geography, Environment, and Spatial Sciences, Michigan State University, East Lansing, USA
| | - Gang Dong
- School of Life Science, Shanxi University, Taiyuan, China
| | - Changliang Shao
- Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China.
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