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1. Variation cascades: resource pulses and top‐down effects across time scales

Author:
Simon, Franz W.; Vasseur, David A.
Source:
Ecology 2021 v.102 no.4 pp. e03277
ISSN:
0012-9658
Subject:
primary productivity,   etc   ; ecosystems; food chain; temporal variation;     Show all 4 Subjects
Abstract:
... Top‐down and bottom‐up theories of trophic control have been fundamental to our understanding of community dynamics and structure. However, most ecological theories have focused on equilibrium dynamics and do not provide predictions for communities’ responses in temporally fluctuating environments. By deriving the frequency response of populations in different trophic communities, we extend the to ...
DOI:
10.1002/ecy.3277

2. Toward sustainable primary production through the application of lean management in South African fruit horticulture

Author:
Pearce, Darian; Dora, Manoj; Wesana, Joshua; Gellynck, Xavier
Source:
Journal of cleaner production 2021 v.313 pp. 127815
ISSN:
0959-6526
Subject:
primary productivity,   etc   ; cluster analysis; farm size; fruits; horticulture; South Africa;     Show all 6 Subjects
Abstract:
... This paper aims to understand the relationship between patterns of lean practice implementation, farm size and sustainable performance among fruit horticultural primary producers in South Africa. Utilizing a comprehensive lean framework, addressing 10 lean practice dimensions, the authors collected data from a sample of 132 fruit farming operations in South Africa. First, cluster analysis was appl ...
DOI:
10.1016/j.jclepro.2021.127815

3. Global patterns of forest autotrophic carbon fluxes

Author:
Banbury Morgan, Rebecca; Herrmann, Valentine; Kunert, Norbert; Bond‐Lamberty, Ben; Muller‐Landau, Helene C.; Anderson‐Teixeira, Kristina J.
Source:
Global change biology 2021 v.27 no.12 pp. 2840-2855
ISSN:
1354-1013
Subject:
net primary productivity,   etc   ; carbon; databases; energy; latitude; metabolism; temperature;     Show all 7 Subjects
Abstract:
... Carbon (C) fixation, allocation, and metabolism by trees set the basis for energy and material flows in forest ecosystems and define their interactions with Earth's changing climate. However, while many studies have considered variation in productivity with latitude and climate, we lack a cohesive synthesis on how forest carbon fluxes vary globally with respect to climate and one another. Here, we ...
DOI:
10.1111/gcb.15574

4. Some thoughts on the biogeochemical cycling of potassium in terrestrial ecosystems

Author:
Schlesinger, William H.
Source:
Biogeochemistry 2021 v.154 no.2 pp. 427-432
ISSN:
0168-2563
Subject:
net primary productivity,   etc   ; commodity prices; potassium; potassium fertilizers; vegetation;     Show all 5 Subjects
Abstract:
... Potassium presents a conundrum for biogeochemists. Potassium is cycled wastefully at the plant level, but it appears to be conserved in the nutrient budgets of entire ecosystems, where it sometimes limits net primary productivity. An increasing demand for K fertilizer may accompany the expansion of agriculture into highly weathered tropical soils, where limited supplies of K may control the distri ...
DOI:
10.1007/s10533-020-00704-4

5. Innovative microcosm experiments for the evaluation of the regeneration rates of nutrients in sediments of a hypersaline lagoon

Author:
Guimarães, Teresa Cristina S.M.; Montenegro, Kaylanne S.; Wasserman, Maria Angélica V.; Wasserman, Julio Cesar
Source:
Marine pollution bulletin 2021 v.166 pp. 112252
ISSN:
0025-326X
Subject:
primary productivity,   etc   ; carbonates; marine pollution; nitrogen; phosphates; seawater; sediments;     Show all 7 Subjects
Abstract:
... The aim of this study was to evaluate the regeneration of nutrients from the sediments to the water column in varying salinities, with an innovative experiment that closely simulates real environment. In vitro experiments were carried out simulating six scenarios with two sediment types (low carbonate and high carbonate). Local water and sediments were added to microcosms where circulation was for ...
DOI:
10.1016/j.marpolbul.2021.112252

6. Assessing invertebrate response to an extreme flood event at a regional scale utilizing past survey data

Author:
Miyake, Yo; Makino, Hiroto; Fukusaki, Kenta
Source:
Limnology 2021 v.22 no.2 pp. 169-177
ISSN:
1439-8621
Subject:
primary productivity,   etc   ; Japan; climate change; limnology; rain; streams; surveys; watersheds;     Show all 8 Subjects
Abstract:
... Climate change is causing frequent and large floods, creating a need for information regarding the impact of severe flood disturbances on stream invertebrates. We briefly describe the response of invertebrate assemblages to an extreme flood event in 2018 in the western Ehime Prefecture of Japan. We compared invertebrate data collected in past regional-scale surveys with those gathered by revisitin ...
DOI:
10.1007/s10201-021-00651-5

7. Performance Assessment of Posidonia oceanica (L.) Delile Restoration Experiment on Dead matte Twelve Years after Planting—Structural and Functional Meadow Features

Author:
Calvo, Sebastiano; Calvo, Roberta; Luzzu, Filippo; Raimondi, Vincenzo; Assenzo, Mauro; Cassetti, Federica Paola; Tomasello, Agostino
Source:
Water 2021 v.13 no.5
ISSN:
2073-4441
Subject:
primary productivity,   etc   ; Posidonia oceanica; humans; meadows; reforestation; seagrasses; water; Sicily;     Show all 8 Subjects
Abstract:
... Following the restoration of natural conditions by reducing human pressures, reforestation is currently considered a possible option to accelerate the recovery of seagrass habitats. Long-term monitoring programs theoretically represent an ideal solution to assess whether a reforestation plan has produced the desired results. Here, we report on the performance of a 20 m² patch of Posidonia oceanica ...
DOI:
10.3390/w13050724

8. Multitrophic diversity sustains ecological complexity by dampening top‐down control of a shallow marine benthic food web

Author:
O’Gorman, Eoin J.
Source:
Ecology 2021 v.102 no.3 pp. e03274
ISSN:
0012-9658
Subject:
primary productivity,   etc   ; crabs; ecosystems; field experimentation; predation; shrimp; species richness;     Show all 7 Subjects
Abstract:
... Biodiversity is typically considered as a one‐dimensional metric (e.g., species richness), yet the consequences of species loss may be different depending on where extinctions occur in the food web. Here, I used a manipulative field experiment in a temperate subtidal marine system to explore the implications of diversity loss at multiple trophic levels for ecosystem functioning and food web struct ...
DOI:
10.1002/ecy.3274

9. Precipitation–productivity relationships and the duration of precipitation anomalies: An underappreciated dimension of climate change

Author:
Felton, Andrew J.; Knapp, Alan K.; Smith, Melinda D.
Source:
Global change biology 2021 v.27 no.6 pp. 1127-1140
ISSN:
1354-1013
Subject:
primary productivity,   etc   ; Biological Sciences; climate change; grasslands; models;     Show all 5 Subjects
Abstract:
... In terrestrial ecosystems, climate change forecasts of increased frequencies and magnitudes of wet and dry precipitation anomalies are expected to shift precipitation–net primary productivity (PPT–NPP) relationships from linear to nonlinear. Less understood, however, is how future changes in the duration of PPT anomalies will alter PPT–NPP relationships. A review of the literature shows strong pot ...
DOI:
10.1111/gcb.15480

10. Circular bioeconomy and environmental benignness through microbial recycling of e-waste: A case study on copper and gold restoration

Author:
Ilyas, Sadia; Srivastava, Rajiv R.; Kim, Hyunjung; Das, Subhankar; Singh, Vinay K.
Source:
Waste management 2021 v.121 pp. 175-185
ISSN:
0956-053X
Subject:
primary productivity,   etc   ; bioeconomics; case studies; copper; electronic wastes; gold; models;     Show all 7 Subjects
Abstract:
... This study has attempted to ascertain the linkages between circular bio-economy (CirBioeco) and recycling of electronic (e-)waste by applying microbial activities instead of the smelter and chemical technologies. To build the research hypothesis, the advances on biotechnology-driven recycling processes for metals extraction from e-waste has been analyzed briefly. Thereafter, based on the potential ...
DOI:
10.1016/j.wasman.2020.12.013

11. Determining dominating control mechanisms of inland water carbon cycling processes and associated gross primary productivity on regional and global scales

Author:
Gao, Yang; Jia, Junjie; Lu, Yao; Yang, Tiantian; Lyu, Sidan; Shi, Kun; Zhou, Feng; Yu, Guirui
Source:
Earth-science reviews 2021 v.213 pp. 103497
ISSN:
0012-8252
Subject:
gross primary productivity,   etc   ; carbon; carbon sequestration; climate; inland waters;     Show all 5 Subjects
Abstract:
... Inland water carbon (C) sequestration rates play a potentially important role in the balance between C supplies from the atmosphere and associated watersheds and the net demand of primary producers. This study conducts a comprehensive analysis of influencing factors associated with inland water C cycling processes as well as their C sequestration potential and gross primary productivity (GPP). Add ...
DOI:
10.1016/j.earscirev.2020.103497

12. Effects of phosphorus control on primary productivity and deep-water oxygenation: insights from Lake Lugano (Switzerland and Italy)

Author:
Lepori, Fabio; Capelli, Camilla
Source:
Hydrobiologia 2021 v.848 no.3 pp. 613-629
ISSN:
0018-8158
Subject:
primary productivity,   etc   ; eutrophication; lakes; models; oxygen; phosphorus; plankton; Italy; Switzerland;     Show all 9 Subjects
Abstract:
... Attempts to restore Lake Lugano, Switzerland and Italy, from eutrophication have produced weak responses in the target variables (primary productivity and hypolimnetic oxygen concentrations), indicating shortcomings in the underlying eutrophication model. An analysis of monitoring data showed that the decrease in phosphorus concentration, although nearly compliant with restoration targets, produce ...
DOI:
10.1007/s10750-020-04467-9

13. Monitoring biomass in two heterogeneous mountain pasture communities by image based 3D point cloud derived predictors

Author:
Passalacqua, Nicodemo G.; Aiello, Simona; Bernardo, Liliana; Gargano, Domenico
Source:
Ecological indicators 2021 v.121 pp. 107126
ISSN:
1470-160X
Subject:
primary productivity,   etc   ; aboveground biomass; conservation status; data collection; ecosystems; pastures;     Show all 6 Subjects
Abstract:
... Primary productivity is a robust indicator of ecosystem functioning because of its close relationships with the stability of the ecological systems. In ecological research, the above ground biomass (AGB) is the most commonly used proxy of primary productivity. However, despite their ecological relevance, the estimates of primary productivity are not addressed by current protocols for monitoring th ...
DOI:
10.1016/j.ecolind.2020.107126

14. Tracing the upwelling process in the northern Benguela upwelling system (nBUS) by 129I

Author:
López-Gutiérrez, José María; Louw, Deon C.; Rožmarić, Martina; Lérida-Toro, Victoria
Source:
Chemosphere 2021 v.265 pp. 129065
ISSN:
0045-6535
Subject:
primary productivity,   etc   ; coasts; mass spectrometry; nuclear fuels; seawater; Monaco; Namibia;     Show all 7 Subjects
Abstract:
... New data on the presence of ¹²⁹I in seawater in the Southern Hemisphere measured by Accelerator Mass Spectrometry (AMS) is presented. The samples were collected in 2014 along the Namibian coast during a cruise organised by the National Marine Information and Research Centre (NatMIRC), the national laboratories of the Ministry of Fisheries and Marine Resources (MFMR) in Namibia, and the IAEA Enviro ...
DOI:
10.1016/j.chemosphere.2020.129065

15. Assessing the degradation of grassland ecosystems based on the advanced local net production scaling method—The case of Inner Mongolia, China

Author:
Lang, Yanqing; Yang, Xiaohuan; Cai, Hongyan
Source:
Land degradation & development 2021 v.32 no.2 pp. 559-572
ISSN:
1085-3278
Subject:
net primary productivity,   etc   ; animal husbandry; ecosystems; grasslands; land degradation; China;     Show all 6 Subjects
Abstract:
... The gradual degradation of grasslands on a global scale goes hand‐in‐hand with significant challenges for agriculture and animal husbandry development. Numerous relevant policies and projects have been implemented to protect and restore Chinese ecosystems, but it is still unclear to what degree grassland ecosystems can be recovered. In view of this, we constructed an advanced local net production ...
DOI:
10.1002/ldr.3741

16. Analysis of Long-Term Changes in Anoxic Zones in the Mozhaisk Reservoir Based on Model Calculations

Author:
Datsenko, Yu. S.; Puklakov, V. V.
Source:
Water resources 2021 v.48 no.1 pp. 48-55
ISSN:
0097-8078
Subject:
primary productivity,   etc   ; ecosystems; eutrophication; hydrologic models; space and time; water;     Show all 6 Subjects
Abstract:
... The results of model calculations of the characteristics of anoxic zones in the Mozhaisk Reservoir over a 57-year period have been analyzed. A two-dimensional box hydrological model of the reservoir has been used to calculate variations of the values of ecological variables with a daily time step. The main regularities in the formation and development of anoxic conditions in different parts of the ...
DOI:
10.1134/S0097807821010139

17. Impacts of two types of errors on the predictability of terrestrial carbon cycle

Author:
Sun, Guodong; Mu, Mu
Source:
Ecosphere 2021 v.12 no.1 pp. e03315
ISSN:
2150-8925
Subject:
net primary productivity,   etc   ; carbon cycle; photosynthesis; prediction; uncertainty; China;     Show all 6 Subjects
Abstract:
... Initial errors and model parameter errors are two of the main factors that produce uncertainties in numerical simulations and predictions. It is crucial to determine in advance which of these types of errors should be reduced to improve numerical simulations and increase their prediction skill. In this study, a fundamental issue related to studies of the predictability about terrestrial carbon cyc ...
DOI:
10.1002/ecs2.3315

18. Investigating factors driving phytoplankton growth and grazing loss rates in waters around Peninsular Malaysia

Author:
Lim, Joon Hai; Lee, Choon Weng; Bong, Chui Wei
Source:
Journal of oceanology and limnology 2021 v.39 no.1 pp. 148-159
ISSN:
2096-5508
Subject:
primary productivity,   etc   ; chlorophyll; eutrophication; limnology; oceanography; phytoplankton; systematic review; Malaysia;     Show all 8 Subjects
Abstract:
... In tropical waters where temperatures are relatively stable, we investigated whether the relationship between phytoplankton growth and grazing loss rate across different habitats around Peninsular Malaysia can be attributed to its eutrophication states. We measured phytoplankton growth (μ) and grazing loss (g) rates in waters off Bachok Marine Research Station (BMRS), located northeast of Peninsul ...
DOI:
10.1007/s00343-020-9227-1

19. Photosynthesis, carbon acquisition and primary productivity of phytoplankton: a review dedicated to Colin Reynolds

Author:
Dokulil, Martin T.; Qian, Kuimei
Source:
Hydrobiologia 2021 v.848 no.1 pp. 77-94
ISSN:
0018-8158
Subject:
primary productivity,   etc   ; algae; carbon; climate change; freshwater; photosynthesis; phytoplankton; rivers;     Show all 8 Subjects
Abstract:
... The review intends to give an overview on developments, success, results of photosynthetic research and on primary productivity of algae both freshwater and marine with emphasis on more recent discoveries. Methods and techniques are briefly outlined focusing on latest improvements. Light harvesting and carbon acquisition are evaluated as a basis of regional and global primary productivity and alga ...
DOI:
10.1007/s10750-020-04321-y

20. The response of productivity and its sensitivity to changes in precipitation: A meta‐analysis of field manipulation experiments

Author:
Zhang, Jiayang; Li, Junyong; Xiao, Rui; Zhang, Jiajia; Wang, Dong; Miao, Renhui; Song, Hongquan; Liu, Yinzhan; Yang, Zhongling; Liu, Mengzhou
Source:
Journal of vegetation science 2021 v.32 no.1 pp. e12954
ISSN:
1100-9233
Subject:
net primary productivity,   etc   ; atmospheric precipitation; forbs; grasses; grasslands; meta-analysis;     Show all 6 Subjects
Abstract:
... QUESTIONS: Changes in precipitation can influence grassland productivity and its sensitivity to precipitation variation, but general patterns remain elusive. METHODS: Using data from 59 studies of experimental precipitation manipulations in grasslands, we tested the effect of increases and decreases in precipitation on above‐ground net primary productivity (ANPP), below‐ground net primary producti ...
DOI:
10.1111/jvs.12954