scholarly journals Effects of management thinning on CO<sub>2</sub> exchange by a plantation oak woodland in south-eastern England

2016 ◽  
Vol 13 (8) ◽  
pp. 2367-2378 ◽  
Author(s):  
Matthew Wilkinson ◽  
Peter Crow ◽  
Edward L. Eaton ◽  
James I. L. Morison
Keyword(s):  
Photosynthetic Rate ◽  
Carbon Balance ◽  
Forest Canopy ◽  
Ecosystem Respiration ◽  
Management Practice ◽  
Canopy Structure ◽  
Soil Surface ◽  
Ground Vegetation ◽  
Significant Difference ◽  
Peak Summer

Abstract. Forest thinning, which removes some individual trees from a forest stand at intermediate stages of the rotation, is commonly used as a silvicultural technique and is a management practice that can substantially alter both forest canopy structure and carbon storage. Whilst a proportion of the standing biomass is removed through harvested timber, thinning also removes some of the photosynthetic leaf area and introduces a large pulse of woody residue (brash) to the soil surface, which potentially can alter the balance of autotrophic and heterotrophic respiration. Using a combination of eddy covariance (EC) and aerial light detection and ranging (lidar) data, this study investigated the effects of management thinning on the carbon balance and canopy structure in a commercially managed oak plantation in the south-east of England. Whilst thinning had a large effect on the canopy structure, increasing canopy complexity and gap fraction, the effects of thinning on the carbon balance were not as evident. In the first year post thinning, the peak summer photosynthetic rate was unaffected by the thinning, suggesting that the better illuminated ground vegetation and shrub layer compensated for the removed trees. Peak summer photosynthetic rate was reduced in the thinned area between 2009 and 2011, but there was no significant difference between sectors. Ecosystem respiration fluxes increased in the thinned relative to the unthinned area in the post-thinning phase.

scholarly journals Effects of management thinning on CO<sub>2</sub> exchange by a plantation oak woodland in south-eastern England

2015 ◽  
Vol 12 (19) ◽  
pp. 16197-16232 ◽  
Author(s):  
M. Wilkinson ◽  
P. Crow ◽  
E. L. Eaton ◽  
J. I. L. Morison
Keyword(s):  
Carbon Balance ◽  
Forest Canopy ◽  
Ecosystem Respiration ◽  
Management Practice ◽  
Canopy Structure ◽  
Net Ecosystem Exchange ◽  
Soil Surface ◽  
Ground Vegetation ◽  
Large Pulse ◽  
Individual Trees

Abstract. Forest thinning, which removes some individual trees from a forest stand at intermediate stages of the rotation, is commonly used as a silvicultural technique and is a management practice that can substantially alter both forest canopy structure and carbon storage. Whilst a proportion of the standing biomass is removed through harvested timber, thinning also removes some of the photosynthetic leaf area and introduces a large pulse of woody residue (brash) to the soil surface which potentially can alter the balance of autotrophic and heterotrophic respiration. Using a combination of eddy covariance (EC) and aerial light detection and ranging (LiDAR) data, this study investigated the effects of management thinning on the carbon balance and canopy structure in a commercially managed oak plantation in the south-east of England. Whilst thinning had a large effect on the canopy structure, increasing canopy complexity and gap fraction, the effects of thinning on the carbon balance were not as evident. In the first year post thinning, Net Ecosystem Exchange (NEE) was unaffected by the thinning, suggesting that the better illuminated ground vegetation and shrub layer partially compensated for the removed trees. NEE was reduced in the thinned area but not until two years after the thinning had been completed (2009); initially this was associated with an increase in ecosystem respiration (Reco). In subsequent years, NEE remained lower with reduced carbon sequestration in fluxes from the thinned area, which we suggest was in part due to heavy defoliation by caterpillars in 2010 reducing GPP in both sectors of the forest, but particularly in the east.

Relationships among burn severity, forest canopy structure and bat activity from spring burns in oak–hickory forests

2017 ◽  
Vol 26 (11) ◽  
pp. 963 ◽  
Author(s):  
Michael J. Lacki ◽  
Luke E. Dodd ◽  
Nicholas S. Skowronski ◽  
Matthew B. Dickinson ◽  
Lynne K. Rieske
Keyword(s):  
Laser Scanning ◽  
Forest Canopy ◽  
Management Practice ◽  
Canopy Structure ◽  
Forest Stand ◽  
Burn Severity ◽  
Prescribed Fires ◽  
Insectivorous Bats ◽  
Conflicting Objectives ◽  
Stand Characteristics

The extent to which prescribed fires affect forest structure and habitats of vertebrate species is an important question for land managers tasked with balancing potentially conflicting objectives of vegetation and wildlife management. Many insectivorous bats forage for insect prey in forested habitats, serving as the primary predators of nocturnal forest insects, and are potentially affected by structural changes in forests resulting from prescribed fires. We compared forest-stand characteristics of temperate oak–hickory forests, as measured with airborne laser scanning (light detection and ranging, LiDAR), with categorical estimates of burn severity from prescribed fires as derived from Landsat data and field-based Composite Burn Indices, and used acoustic monitoring to quantify activity of insectivorous bats in association with varying degrees of burn severity (unburned habitat, low severity and medium severity). Forest-stand characteristics showed greatest separation between low-severity and medium-severity classes, with gap index, i.e. open-air space, increasing with degree of burn severity. Greater mid-storey density, over-storey density and proportion of vegetation in the understorey occurred in unburned habitat. Activity of bats did not differ with burn severity for high-frequency (clutter-adapted or closed-space foragers) or low-frequency (edge or open-space foragers) bats. Results indicate that differing degrees of burn severity from prescribed fires produced spatial variation in canopy structure within stands; however, bats demonstrated no shifts in activity levels to this variation in canopy structure, suggesting prescribed fire during the dormant season, used as a management practice targeting desired changes in vegetation, is compatible with sustaining foraging habitat of insectivorous bats.

scholarly journals Inter-annual variation of carbon uptake by a plantation oak woodland in south-eastern England

2012 ◽  
Vol 9 (7) ◽  
pp. 9667-9710 ◽  
Author(s):  
M. Wilkinson ◽  
E. L. Eaton ◽  
M. S. J. Broadmeadow ◽  
J. I. L. Morison
Keyword(s):  
Carbon Balance ◽  
Forest Canopy ◽  
Annual Variation ◽  
Ecosystem Respiration ◽  
Growing Season ◽  
Co2 Uptake ◽  
Operophtera Brumata ◽  
Area Index ◽  
Growing Season Length ◽  
Net Co2 Uptake

Abstract. The carbon balance of an 80 yr old deciduous oak plantation in the temperate oceanic climate of the south-east of Britain was measured by eddy covariance over 12 yr (1999–2010). The mean annual net ecosystem productivity (NEP) was 486 g C m−2 y−1 (95% CI of ±73 g C m−2 y−1), and this was partitioned into a Gross Primary Productivity (GPP) of 2034 ± 145 g C m−2 y−1, over a 165 (±6) day growing season, and an annual loss of carbon through respiration and decomposition (ecosystem respiration, Reco) of 1548 ± 122 g C m−2 y−1. The interannual variation of NEP was large (coefficient of variation (CV) 23%), although the variation for GPP and Reco was smaller (12%) and the ratio of Reco/GPP was relatively constant (0.76 ± 0.02 CI). Some anomalies in the annual patterns of the carbon balance could be linked to particular combinations of anomalous weather events, such as high summer air temperature and low soil moisture content. The Europe-wide heat-wave and drought of 2003 had little effect on the C balance of this woodland on a surface water gley soil. Annual variation in precipitation (CV 18%) was not a main factor in the variation in NEP. The inter-annual variation in estimated intercepted radiation only accounted for ~ 47% of the variation in GPP, although a significant relationship (p<0.001) was found between peak leaf area index and annual GPP which in turn played an important role in modifying the efficiency with which incident radiation was used in net CO2 uptake. Whilst the spring start and late autumn end of the net CO2 uptake period varied substantially (range of 24 and 27 days, respectively), annual GPP was not related to growing season length. Severe outbreaks of defoliating moth caterpillars, mostly Tortrix viridana L. and Operophtera brumata L., caused considerable damage to the forest canopy in 2009 and 2010, resulting in reduced GPP in these years.

scholarly journals Forest floor temperature and greenness link significantly to canopy attributes in South Africa’s fragmented coastal forests

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e6190
Author(s):  
Marion Pfeifer ◽  
Michael J.W. Boyle ◽  
Stuart Dunning ◽  
Pieter I. Olivier
Keyword(s):  
Land Use ◽  
Surface Temperature ◽  
Habitat Quality ◽  
Forest Canopy ◽  
Canopy Structure ◽  
Ground Surface ◽  
Ground Vegetation ◽  
Canopy Closure ◽  
Ground Surface Temperature ◽  
Vegetation Greenness

Tropical landscapes are changing rapidly due to changes in land use and land management. Being able to predict and monitor land use change impacts on species for conservation or food security concerns requires the use of habitat quality metrics, that are consistent, can be mapped using above-ground sensor data and are relevant for species performance. Here, we focus on ground surface temperature (Thermalground) and ground vegetation greenness (NDVIdown) as potentially suitable metrics of habitat quality. Both have been linked to species demography and community structure in the literature. We test whether they can be measured consistently from the ground and whether they can be up-scaled indirectly using canopy structure maps (Leaf Area Index, LAI, and Fractional vegetation cover, FCover) developed from Landsat remote sensing data. We measured Thermalground and NDVIdown across habitats differing in tree cover (natural grassland to forest edges to forests and tree plantations) in the human-modified coastal forested landscapes of Kwa-Zulua Natal, South Africa. We show that both metrics decline significantly with increasing canopy closure and leaf area, implying a potential pathway for upscaling both metrics using canopy structure maps derived using earth observation. Specifically, our findings suggest that opening forest canopies by 20% or decreasing forest canopy LAI by one unit would result in increases of Thermalground by 1.2 °C across the range of observations studied. NDVIdown appears to decline by 0.1 in response to an increase in canopy LAI by 1 unit and declines nonlinearly with canopy closure. Accounting for micro-scale variation in temperature and resources is seen as essential to improve biodiversity impact predictions. Our study suggests that mapping ground surface temperature and ground vegetation greenness utilising remotely sensed canopy cover maps could provide a useful tool for mapping habitat quality metrics that matter to species. However, this approach will be constrained by the predictive capacity of models used to map field-derived forest canopy attributes. Furthermore, sampling efforts are needed to capture spatial and temporal variation in Thermalground within and across days and seasons to validate the transferability of our findings. Finally, whilst our approach shows that surface temperature and ground vegetation greenness might be suitable habitat quality metric used in biodiversity monitoring, the next step requires that we map demographic traits of species of different threat status onto maps of these metrics in landscapes differing in disturbance and management histories. The derived understanding could then be exploited for targeted landscape restoration that benefits biodiversity conservation at the landscape scale.

scholarly journals Changes in peanut canopy structure and photosynthetic characteristics induced by an arbuscular mycorrhizal fungus in a nutrient-poor environment

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yinli Bi ◽  
Huili Zhou
Keyword(s):  
Net Photosynthetic Rate ◽  
Leaf Area ◽  
Photosynthetic Rate ◽  
Mycorrhizal Fungus ◽  
Canopy Structure ◽  
Arbuscular Mycorrhizal ◽  
Photosynthetic Characteristics ◽  
Total Leaf Area ◽  
Tiller Angle ◽  
Amf Inoculation

AbstractA well-developed canopy structure can increase the biomass accumulation and yield of crops. Peanut seeds were sown in a soil inoculated with an arbuscular mycorrhizal fungus (AMF) and uninoculated controls were also sown. Canopy structure was monitored using a 3-D laser scanner and photosynthetic characteristics with an LI-6400 XT photosynthesis system after 30, 45 and 70 days of growth to explore the effects of the AMF on growth, canopy structure and photosynthetic characteristics and yield. The AMF colonized the roots and AMF inoculation significantly increased the height, canopy width and total leaf area of the host plants and improved canopy structure. AMF reduced the tiller angle of the upper and middle canopy layers, increased that of the lower layer, reduced the leaf inclination of the upper, middle and lower layers, and increased the average leaf area and leaf area index after 45 days of growth, producing a well-developed and hierarchical canopy. Moreover, AMF inoculation increased the net photosynthetic rate in the upper, middle and lower layers. Plant height, canopy width, and total leaf area were positively correlated with net photosynthetic rate, and the inclination angle and tiller angle of the upper leaves were negatively correlated with net photosynthetic rate. Overall, the results demonstrate the effects of AMF inoculation on plant canopy structure and net photosynthetic rate.

Drone-acquired data reveal the importance of forest canopy structure in predicting tree diversity

2022 ◽  
Vol 505 ◽  
pp. 119945
Author(s):  
Jian Zhang ◽  
Zhaochen Zhang ◽  
James A. Lutz ◽  
Chengjin Chu ◽  
Jianbo Hu ◽  
...  
Keyword(s):  
Forest Canopy ◽  
Canopy Structure ◽  
Tree Diversity

scholarly journals The Relationship between Sport Organizational Management Practices and Coaching Leadership Style of Primer League Football Clubs in Ethiopian

2018 ◽  
Vol 7 (1) ◽  
pp. 25-31
Author(s):  
Biruk Hundito ◽  
N Vijay Mohan
Keyword(s):  
Data Analysis ◽  
Leadership Style ◽  
Management Practices ◽  
Management Practice ◽  
Organizational Management ◽  
Football Clubs ◽  
Leadership Behaviour ◽  
Significant Difference ◽  
Coaching Leadership ◽  
The Relationship

The major purpose of this study was to investigate the relationship between sport organizational management practices and coaching leadership style of Ethiopian primer league football clubs. To this end descriptive survey method were employed. The data collected by two Questionnaires the first one from sport organizational management practices and the second one Leadership Scale for Sport (LSS) from selected football club players. Assess the validity and reliability of the questionnaires by areas of professional expertise. The target population of this study were all 14 Ethiopian primer league football club players. Based on Ethiopian football federation rules and regulations 25 players registered for one year computation 25x14(N=350).The researcher selected only 4(28.57%) top two and bottom tow clubs from 2015/2016 computation year by using purposive sampling techniques. The total number of participants in this study was 4x25(N=100). The research approach applied for this study were quantitative approach in nature. The Statistical Package for Social Science (SPSS) version 20 used for data analysis Depending on the nature of the basic questions, appropriate statistical techniques such as mean, standard deviation, ANOVA (analysis of variance) ,and Pearson correlation were used for data analysis. The level of significance is set at 0.05. The researcher assumption/hypothesis was: - There is no significant difference in sport organizational management practices, Perceive and Prefer of coaching leadership behaviour of player’s indices in Ethiopian premier league football clubs. The study findings indicated that, there is significant difference between clubs and sport organizational management practice, there is significant difference between clubs and perceive coaching leadership style and there is no significant difference between clubs and prefer coaching leadership style. Finally there was positive relationship in sport organizational management practice, perceive and prefer of coaching leadership behaviour.

scholarly journals Development of а matrix of food industry capacity for making management decisions in the formation of sustainable development of agroecosystems

2021 ◽  
Vol 2 (13 (110)) ◽  
pp. 16-27
Author(s):  
Kateryna Andriushchenko ◽  
Oleksandr Datsii ◽  
Oksana Lavruk ◽  
Ruslan Dmytrenko ◽  
Igor Kutashev ◽  
...  
Keyword(s):  
Sustainable Development ◽  
Food Industry ◽  
System Analysis ◽  
Agricultural Sector ◽  
Financial Analysis ◽  
Management Practice ◽  
Sensitivity Factor ◽  
Management Decisions ◽  
Significant Difference ◽  
The Matrix

A theoretical and methodological study was carried out to determine the need and features of developing a matrix of food industry capacity for making management decisions in the formation of sustainable development of agroecosystems, which will increase the operational efficiency of companies and food security of the country. The paper uses the following research methods: historical – in the process of studying modern views on understanding the importance of the agricultural sector for the economy; system analysis – when building a model of innovative business improvement. Methods of comparison and analysis of trends – the study of trends in the agricultural sector of Ukraine with the identification of important areas for improving their activities. Methods of financial analysis – for the analytical assessment of financial and economic activities of the investigated enterprises; forecasting methods – to substantiate the expected results of implementing the author's proposals in management practice. It is proposed to take into account the significant difference in the technology of their processing and production (number of advanced technologies used per 100 thousand people). The paper reveals the dependence of production technologies in agriculture on natural and weather conditions (share of technological innovation costs, %). Criteria for innovation skills in the development of agricultural engineering were proposed. The criteria were determined, which were divided into development groups. The tools for constructing a matrix of food industry capacity were substantiated. Note that for each indicator, the optimal value was determined taking into account the sensitivity factor and the rating of enterprises, which determined their place in the matrix. In the course of the study and the matrix of innovative development, the proposed technology was tested at leading domestic enterprises

scholarly journals High Rates of Ecosytem Metabolism in Five Western Rivers

2011 ◽  
Vol 33 ◽  
pp. 115-118
Author(s):  
Robert Hall ◽  
Jennifer Tank ◽  
Michelle Baker ◽  
Emma Rosi-Marshall ◽  
Michael Grace ◽  
...  
Keyword(s):  
Organic Carbon ◽  
Primary Production ◽  
Carbon Cycling ◽  
Carbon Balance ◽  
Carbon Fixation ◽  
Higher Plants ◽  
Ecosystem Respiration ◽  
Gross Primary Production ◽  
Total Rate ◽  
Global Carbon

Primary production and respiration are core functions of river ecosystems that in part determine the carbon balance. Gross primary production (GPP) is the total rate of carbon fixation by autotrophs such as algae and higher plants and is equivalent to photosynthesis. Ecosystem respiration (ER) measures rate at which organic carbon is mineralized to CO2 by all organisms in an ecosystem. Together these fluxes can indicate the base of the food web to support animal production (Marcarelli et al. 2011), can predict the cycling of other elements (Hall and Tank 2003), and can link ecosystems to global carbon cycling (Cole et al. 2007).

scholarly journals Water repellency of clay, sand and organic soils in Finland

2008 ◽  
Vol 16 (3) ◽  
pp. 267 ◽  
Author(s):  
K. RASA ◽  
R. HORN ◽  
M. RÄTY
Keyword(s):  
Preferential Flow ◽  
Management Practice ◽  
Soil Surface ◽  
Water Repellency ◽  
Organic Soil ◽  
Water Infiltration ◽  
Organic Soils ◽  
Water Repellent ◽  
Moisture Regime ◽  
Wetting Process

Water repellency (WR) delays soil wetting process, increases preferential flow and may give rise to surface runoff and consequent erosion. WR is commonly recognized in the soils of warm and temperate climates. To explore the occurrence of WR in soils in Finland, soil R index was studied on 12 sites of different soil types. The effects of soil management practice, vegetation age, soil moisture and drying temperature on WR were studied by a mini-infiltrometer with samples from depths of 0-5 and 5-10 cm. All studied sites exhibited WR (R index >1.95) at the time of sampling. WR increased as follows: sand (R = 1.8-5.0) < clay (R = 2.4-10.3) < organic (R = 7.9-undefined). At clay and sand, WR was generally higher at the soil surface and at the older sites (14 yr.), where organic matter is accumulated. Below 41 vol. % water content these mineral soils were water repellent whereas organic soil exhibited WR even at saturation. These results show that soil WR also reduces water infiltration at the prevalent field moisture regime in the soils of boreal climate. The ageing of vegetation increases WR and on the other hand, cultivation reduces or hinders the development of WR.;

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