Particle Retention Capacity, Efficiency, and Mechanism of Selected Plant Species: Implications for Urban Planting for Improving Urban Air Quality

Atmospheric particulate matter (PM) has been of concern owing to its negative effects on human health and its role in environmental degradation. For mitigation purposes, it is important to select the most efficient plant species in urban greening. Here, a fast, cost-saving methodology was first added to the conventional method to investigate the size-resolved PM retention capacity and efficiency of twenty plant species. Surface PM (SPM), which can be removed by water and brushing, accounted for 44.9%−66.9% of total PM, in which the water-soluble PM (DPM) accounted for 12.9%−22.1% of total PM. A large mass proportion of in-wax PM (14.1%−31.7%) was also observed. Platycladus orientalis, Eriobotrya japonica, Viburnum odoratissimum, Magnolia grandiflora had the highest AEleaf (retention efficiency on per unit leaf area) to retain SPM within different diameter classes (DPM, PM0.1-2.5, PM2.5-10, PM>10). AEplant (retention efficiency of individual tree) varied greatly among different plant species, mainly due to the dependence on the total area of a tree. AEland (retention efficiency on per unit green area) is a suitable index for PM retention ability and efficiency. In general, P. orientalis, V. odoratissimum, Pittosporum tobira, Photinia serrulate, M. grandiflora, E. japonica were the efficient species in retaining PM at different scales (i.e., leaf, individual tree, green area). The species like Trifolium repens, Phyllostachys viridis, were the least efficient plant species. The investigated species are all evergreen species, which will remove PM throughout the whole year, even in winter. So, we recommended that the plant species with the highest PM retention efficiency can be used in urban greening. Meanwhile, horticulture practices should also be considered to improve the leaf area index to improve their PM retention and air purification abilities.

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Effect of previous cutting interval and of leaf area remaining after cutting on regrowth of Macroptilium atropurpureum cv. Siratro

Australian Journal of Experimental Agriculture ◽

10.1071/ea9740343 ◽

1974 ◽

Vol 14 (68) ◽

pp. 343 ◽

Cited By ~ 2

Author(s):

RJ Jones

Keyword(s):

Leaf Area ◽

Practical Implication ◽

Soluble Sugars ◽

Ground Level ◽

Fold Increase ◽

Water Soluble ◽

Hot Water ◽

Lag Phase ◽

Area Index ◽

Plant Yield

Experiments with Siratro were conducted at Samford, south east Queensland to study the effects of previous cutting and defoliation treatments on regrowth. In the first experiment, swards of Siratro were cut at 7.5 cm above ground level every 4 weeks, every 8 weeks or cut once at 16 weeks during spring and summer. Regrowth of all treatments over ten weeks was measured after varying (by leaf removal) the stubble leaf area index (LAI) of the plots cut every four weeks. Pattern of regrowth yield was similar for all treatments with a pronounced lag phase after cutting. Regrowth yield after 10 weeks differed between treatments and was linearly related (P < 0.01 ) to residual LAI in the stubble at the start of regrowth. In the absence of stubble leaves, plots previously cut at 16 weeks or at 8 weeks yielded marginally more than those cut every 4 weeks. There were no marked treatment differences in gross root morphology other than a two fold increase in stolon rooting for the 16-week treatment. Nitrogen content of the roots (mean 1.38 per cent) was unaffected by treatment, but the per cent hot water soluble sugars were lower for the 16 week defoliation treatment than for the 8-week and the 4-week treatments. In the second experiment individual plants were cut to a uniform stubble every 4 weeks and either 0, 5, or 10 leaves were left. Dry weight of regrowth and stolon development were greatest when most leaves were left. Two thirds of the plants died after six cuttings with complete defoliation but none died when either 5 or 10 leaves were retained. Plant survival was not related to plant yield or degree of stoloniferous development. However, there was a strong correlation between stolon number and plant yield under this intensive cutting regime. The practical implication of the results in the management of Siratro is discussed.

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Relationships of NDVI, Biomass, and Leaf Area Index (LAI) for six key plant species in Barrow, Alaska

10.7287/peerj.preprints.913v1 ◽

2015 ◽

Cited By ~ 6

Author(s):

Santonu Goswami ◽

John Gamon ◽

Sergio Vargas ◽

Craig Tweedie

Keyword(s):

Leaf Area Index ◽

Leaf Area ◽

Plant Species ◽

Vegetation Index ◽

Plant Biomass ◽

Plant Cover ◽

Strongly Correlated ◽

Area Index ◽

Spectral Bands ◽

Biomass Plant

Here we investigate relationships between NDVI, Biomass, and Leaf Area Index (LAI) for six key plant species near Barrow, Alaska. We explore how key plant species differ in biomass, leaf area index (LAI) and how can vegetation spectral indices be used to estimate biomass and LAI for key plant species. A vegetation index (VI) or a spectral vegetation index (SVI) is a quantitative predictor of plant biomass or vegetative vigor, usually formed from combinations of several spectral bands, whose values are added, divided, or multiplied in order to yield a single value that indicates the amount or vigor of vegetation. For six key plant species, NDVI was strongly correlated with biomass (R2 = 0.83) and LAI (R2 = 0.70) but showed evidence of saturation above a biomass of 100 g/m2 and an LAI of 2 m2/m2. Extrapolation of a biomass-plant cover model to a multi-decadal time series of plant cover observations suggested that Carex aquatilis and Eriophorum angustifolium decreased in biomass while Arctophila fulva and Dupontia fisheri increased 1972-2008.

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Response of red chilli (Capsicum annuum L.) to fertigation and mulching

International Journal of Agricultural Invention ◽

10.46492/ijai/2017.2.2.11 ◽

2017 ◽

Vol 2 (02) ◽

pp. 169-173

Author(s):

G. Chandramohan Reddy ◽

S. S. Hebbar

Keyword(s):

Leaf Area ◽

Capsicum Annuum ◽

Growth Parameters ◽

Fruit Yield ◽

Water Soluble ◽

Growth And Yield ◽

Index Number ◽

Area Index ◽

Capsicum Annuum L ◽

Dry Fruit

Experiments were conducted to evaluate the performance of red chilli (Capsicum annuum L.) during 2015-16 at the Division of vegetable crops, Indian Institute of Horticulture Research, Hessaraghatta, Bangalore to determine the effect of different fertigation sources and mulching on growth parameters, yield and fertilizer use efficiency (FUE). Fertigation was done both water soluble fertilizers and normal fertilizers with different doses. The results revealed that significantly higher growth and yield parameters viz., plant height (cm), number of branches per plant, leaf area and leaf area index, number of fruits per plant, length of the fruit (cm), girth of the fruit (cm), fruit weight (g) dry fruit yield per plant (g), dry fruit yield per hectare (t) were observed by the treatments viz., application of water soluble fertilizers 100 per cent (Recommended dose of fertilizers) RDF using urea, 19:19:19 and KNO3 through fertigation with mulching, followed by Normal fertilizers 100 per cent RDF using Urea, DAP, MOP through fertigation with mulching. From this investigation it is concluded that water soluble fertilizers as well as normal fertilizers fertigation with mulching ideal for maximum growth and yield of the chilli crop.

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Leaf Area and Competition for Light between Plant Species using Direct Sunlight Transmission

Weed Technology ◽

10.1017/s0890037x00030311 ◽

1988 ◽

Vol 2 (2) ◽

pp. 159-165 ◽

Cited By ~ 33

Author(s):

Graham K. Walker ◽

Robert E. Blackshaw ◽

Jack Dekker

Keyword(s):

Leaf Area ◽

Plant Species ◽

Chenopodium Album ◽

Field Studies ◽

Individual Species ◽

Light Competition ◽

Direct Sunlight ◽

Area Index ◽

Wild Mustard ◽

Competition For Light

A technique based on the relationship between leaf area index (LAI) and the transmittance of direct sunlight was developed for thein situstudy of competition for light between plant species. Field studies were conducted in 1984 and 1985 using monocultures and mixtures of rapeseed (Brassica napusL.), wild mustard (Sinapis arvensisL. # SINAR), and common lambsquarters (Chenopodium albumL. # CHEAL). LAI estimated nondestructively by this method agreed closely with LAI determined by conventional destructive techniques. Light measurements at several heights in the canopy were used to determine the vertical distribution of canopy leaf area. Combining this information with species heights allowed the separation of the canopy LAI into individual species LAI, from which light competition could be estimated by calculating the sunlit LAI of each species. The technique permits many detailed measurements in the same canopy throughout the growing season. The light sensor required is not costly and is simple to operate and to maintain.

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Monitoring crop growth inter-annual variability from MODIS time series: Performance comparison between crop specific green area index and current global leaf area index products

2011 6th International Workshop on the Analysis of Multi-temporal Remote Sensing Images (Multi-Temp) ◽

10.1109/multi-temp.2011.6005037 ◽

2011 ◽

Author(s):

Gregory Duveiller ◽

Frederic Baret ◽

Pierre Defourny

Keyword(s):

Time Series ◽

Leaf Area Index ◽

Leaf Area ◽

Crop Growth ◽

Performance Comparison ◽

Area Index ◽

Annual Variability ◽

Green Area

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Retrieval of Vertical Foliage Profile and Leaf Area Index Using Transmitted Energy Information Derived from ICESat GLAS Data

Remote Sensing ◽

10.3390/rs12152457 ◽

2020 ◽

Vol 12 (15) ◽

pp. 2457

Author(s):

Lei Cui ◽

Ziti Jiao ◽

Kaiguang Zhao ◽

Mei Sun ◽

Yadong Dong ◽

...

Keyword(s):

Radiative Transfer ◽

Leaf Area Index ◽

Leaf Area ◽

Transfer Model ◽

Simulation Data ◽

Individual Tree ◽

Area Index ◽

Transmitted Energy ◽

Modis Lai ◽

Vertical Gap

The vertical foliage profile (VFP) and leaf area index (LAI) are critical descriptors in terrestrial ecosystem modeling. Although light detection and ranging (lidar) observations have been proven to have potential for deriving the VFP and LAI, existing methods depend only on the received waveform information and are sensitive to additional input parameters, such as the ratio of canopy to ground reflectance. In this study, we proposed a new method for retrieving forest VFP and LAI from Ice, Cloud and land Elevation Satellite (ICESat) Geoscience Laser Altimeter System (GLAS) data over two sites similar in their biophysical parameters. Our method utilized the information from not only the interaction between the laser and the forest but also the sensor configuration, which brought the benefit that our method was free from an empirical input parameter. Specifically, we first derived the transmitted energy profile (TEP) through the lidar 1-D radiative transfer model. Then, the obtained TEP was utilized to calculate the vertical gap distribution. Finally, the vertical gap distribution was taken as input to derive the VFP based on the Beer–Lambert law, and the LAI was calculated by integrating the VFP. Extensive validations of our method were carried out based on the discrete anisotropic radiative transfer (DART) simulation data, ground-based measurements, and the Moderate Resolution Imaging Spectroradiometer (MODIS) LAI product. The validation based on the DART simulation data showed that our method could effectively characterize the VFP and LAI under various canopy architecture scenarios, including homogeneous turbid and discrete individual-tree scenes. The ground-based validation also proved the feasibility of our method: the VFP retrieved from the GLAS data showed a similar trend with the foliage distribution density in the GLAS footprints; the GLAS LAI had a high correlation with the field measurements, with a determination coefficient (R2) of 0.79, root mean square error (RMSE) of 0.49, and bias of 0.17. Once the outliers caused by low data quality and large slope were identified and removed, the accuracy was further improved, with R2 = 0.85, RMSE = 0.35, and bias = 0.10. However, the MODIS LAI product did not present a good relationship with the GLAS LAI. Relative to the GLAS LAI, the MODIS LAI showed an overestimation in the low and middle ranges of the LAI and a saturation at high values of approximately LAI = 5.5. Overall, this method has the potential to produce continental- and global-scale VFP and LAI datasets from the spaceborne lidar system.

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Estimating leaf area index and light extinction coefficients in stands of Douglas-fir (Pseudotsugamenziesii)

Canadian Journal of Forest Research ◽

10.1139/x93-043 ◽

1993 ◽

Vol 23 (2) ◽

pp. 317-321 ◽

Cited By ~ 24

Author(s):

Nicholas J. Smith

Keyword(s):

Leaf Area Index ◽

Leaf Area ◽

Extinction Coefficient ◽

Photosynthetically Active Radiation ◽

Douglas Fir ◽

Regression Equations ◽

Individual Tree ◽

Area Index ◽

Active Radiation ◽

Wide Range

Both photosynthetically active radiation penetrating the overstory canopy and overstory leaf area index were determined in forty-three 12 × 12 m plots in even-aged Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) stands. Stands were located on the east side of Vancouver Island, British Columbia, between 300 and 800 m on flat to south-facing slopes and were from a wide range of stem densities and stocking levels. In nine core plots total tree leaf area index was estimated using regression equations from individual-tree stem diameter and stand relative density. A single extinction coefficient did not govern the attenuation of photosynthetically active radiation with respect to leaf area index. For a given leaf area index, the extinction coefficient was smaller at low relative densities because of the presence of canopy gaps. Light attenuation models assuming a single extinction coefficient seriously underpredict stand leaf area index, especially at low stand densities. A modified Beer's Law model was used to predict light penetration, which implicitly accounted for foliage clumping.

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Relationships of NDVI, Biomass, and Leaf Area Index (LAI) for six key plant species in Barrow, Alaska

10.7287/peerj.preprints.913 ◽

2015 ◽

Cited By ~ 3

Author(s):

Santonu Goswami ◽

John Gamon ◽

Sergio Vargas ◽

Craig Tweedie

Keyword(s):

Leaf Area Index ◽

Leaf Area ◽

Plant Species ◽

Vegetation Index ◽

Plant Biomass ◽

Plant Cover ◽

Strongly Correlated ◽

Area Index ◽

Spectral Bands ◽

Biomass Plant

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Stand Delineation of Pinus sylvestris L. Plantations Suffering Decline Processes Based on Biophysical Tree Crown Variables: A Necessary Tool for Adaptive Silviculture

Remote Sensing ◽

10.3390/rs13030436 ◽

2021 ◽

Vol 13 (3) ◽

pp. 436

Author(s):

Mª Ángeles Varo-Martínez ◽

Rafael M. Navarro-Cerrillo

Keyword(s):

Pinus Sylvestris ◽

Leaf Area Index ◽

Leaf Area ◽

Vegetation Index ◽

Vegetation Indices ◽

Classification Model ◽

Similar Response ◽

Tree Crown ◽

Individual Tree ◽

Area Index

Many planted Pinus forests are severely affected by defoliation and mortality processes caused by pests and droughts. The mapping of forest tree crown variables (e.g., leaf area index and pigments) is particularly useful in stand delineation for the management of declining forests. This work explores the potential of integrating multispectral WorldView-2 (WV-2) and Airborne Laser Scanning (ALS) data for stand delineation based on selected tree crown variables in Pinus sylvestris plantations in southern Spain. Needle pigments (chlorophyll and carotenes) and leaf area index (LAI) were quantified. Eight vegetation indices and ALS-derived metrics were produced, and seven predictors were selected to estimate and map tree crown variables using a Random Forest method and Gini index. Chlorophylls a and b (Chla and Chlb) were significantly higher in the non-defoliated and moderately defoliated trees than in severely defoliated trees (F = 14.02, p < 0.001 for Chla; F = 13.09, p < 0.001 for Chlb). A similar response was observed for carotenoids (Car) (F = 14.13, p < 0.001). The LAI also showed significant differences among the defoliation levels (F = 26.5, p < 0.001). The model for the chlorophyll a pigment used two vegetation indices, Plant Senescence Reflectance Index (PSRI) and Carotenoid Reflectance Index (CRI); three WV-2 band metrics, and three ALS metrics. The model built to describe the tree Chlb content used similar variables. The defoliation classification model was established with a single vegetation index, Green Normalized Difference Vegetation Index (GNDVI); two metrics of the blue band, and two ALS metrics. The pigment contents models provided R2 values of 0.87 (Chla, RMSE = 12.98%), 0.74 (Chlb, RMSE = 10.39%), and 0.88 (Car, RMSE = 10.05%). The cross-validated confusion matrix achieved a high overall classification accuracy (84.05%) and Kappa index (0.76). Defoliation and Chla showed the validation values for segmentations and, therefore, in the generation of the stand delineation. A total of 104 stands were delineated, ranging from 6.96 to 54.62 ha (average stand area = 16.26 ha). The distribution map of the predicted severity values in the P. sylvestris plantations showed a mosaic of severity patterns at the stand and individual tree scales. Overall, the findings of this work underscore the potential of WV-2 and ALS data integration for the assessment of stand delineation based on tree health status. The derived cartography is a relevant tool for developing adaptive silvicultural practices to reduce Pinus sylvestris mortality in planted forests at risk due to climate change.

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