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New tree monitoring systems: from Industry 4.0 to Nature 4.0

November 2019

DOI:10.12899/asr-1847

Authors:

Riccardo Valentini

University of Tuscia

Luca Belelli Marchesini

Fondazione Edmund Mach - Istituto Agrario San Michele All'Adige

Giovanna Sala

University of Palermo

Alexey Mihailovich Yaroslavtsev

Russian State Agrarian University - Moscow Timiryazev Agricultural Academy

Show all 6 authorsHide

Recently, Internet of Things (IoT) technologies have grown rapidly and represent now a unique opportunity to improve our environmental monitoring capabilities at extremely low costs. IoT is a new system of thinking in which objects, animals or people are equipped with unique identifiers and transfer data a network without requiring human-to-human or human-to-computer interaction. IoT has evolved from the convergence of wireless technologies, microelectromechanical systems (MEMS) and the Internet. The development of these technologies in environmental monitoring domains allows real-time data transmission and numerous low-cost monitoring points. We have designed a new device, the TreeTalker©, which is capable of measuring water transport in trees, diametrical growth, spectral characteristics of the leaves and microclimatic parameters and transmit data in semi-real time. Here we introduce the device’s features, provide an example of monitored data from a field test site and discuss the application of this new technology to tree monitoring in various contexts, from forest to urban green infrastructures management and ecological research.

Tree-Talker installed for the monitoring of a tree and its power unit (battery case with photovoltaic panel).

…

Hourly data of sapflow density flux (green line) and vapor pressure deficit (VPD, blue line) measured over three days in early September 2018 at the MTAA test site. VPD was calculated from air temperature and relative humidity measured within the TT case.

…

Pattern of air temperature (blue line, hourly data) and NDVI (boxplots, daily data) measured between 1 September and 31 October 2018 capturing the progression of leaf senescence phase.

…

Stem radial growth of a Douglas fir specimen at the Piegaro forest site inferred from variations of the sensor to tree trunk distance. Original hourly data (blue line) and moving average (n=24; red line) showing the trend of radial growth.

…

Figures - uploaded by Luca Belelli Marchesini

Content may be subject to copyright.

Content uploaded by Luca Belelli Marchesini

Content may be subject to copyright.

An n A ls of silv ic u ltu rAl re s e Arc h

43 (2), 2019: 84-88

https://journals-crea.4science.it/index.php/asr

Technical Note

http://dx.doi.org/10.12899/asr-1847

1 Department for Innovation in Biological, Agro-Food and Forest Systems, University of Tuscia, Viterbo, Italy

2 Department of Sustainable Agro-ecosystems and Bioresources, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all’Adige, Italy

3 Department of Landscape Design and Sustainable Ecosystems, Agrarian‐Technological Institute, RUDN University, Moscow, Russia

4 LAMP, Russian Timiryazev State Agrarian University, Moscow, Russia

5 University of Campania “Luigi Vanvitelli”, Caserta, Italy

*Corresponding author: luca.belelli@gmail.com

Collection: “4th Italian National Congress of Silviculture” - Torino, 5-9 November 2018

Introduction

In recent years, a new trend in manufacturing

technologies, generally referred to as Industry 4.0,

has emerged, allowing to achieve a higher level of

operational efﬁciency and productivity through au-

tomated and interconnected systems (Roblek et al.

2016). This was due to the combination of the tech-

nological concepts of cyber-physical systems and

Internet of Things (IoT), a new paradigm according

to which objects, but also living beings, can transfer

univocally identiﬁed data to the internet without the

interaction of humans (Misra et al. 2018). The IoT

evolved from the convergence of wireless technolo-

gies, microelectromechanical systems (MEMS) and

the Internet.

Industry 4.0 has indeed brought a major break-

through in the ﬁeld of industrial processes monitor-

ing and it is therefore reckoned to represent a new

stage, equivalent to a “Fourth Industrial Revolution”,

from which takes its name. The translation of such

technologies into the ﬁeld of environmental moni-

toring could bring the advantage of real-time data

transmission from numerous measurement points

at low cost, however, the applications to nature un-

derstanding and management are to date generally

lacking.

Drawing inspiration from the concept of Indus-

try 4.0, we, therefore, conceived the application of a

system to the monitoring of physical and functional

parameters of trees, in what can be deﬁned as the

Nature 4.0 approach. The implementation of such an

observation system should be based on digital sen-

sors featuring continuous operability and automatic

data transmission in order to provide semi-real time

monitoring of variables. Moreover it will represent

both a decision support framework for environmen-

tal management – and a valid tool for scientiﬁc re-

search in the ﬁeld of trees ecology and ecophysiolo-

gy (Bayne et al. 2017, Subashini et al. 2018).

The interest of managers of urban green in-

frastructures or forests would lie primarily in the

constantly updated diagnosis of trees conditions

relative to their vigour, growth rate and failure risk;

spatially punctual and temporally dense data on the

microclimate surrounding trees, their canopy spec-

tral properties and functionality in terms of growth

and water transport would provide researchers with

insight on individual trees functional responses to

their environment.

We developed a new multifunctional device, the

“TreeTalker©”, based on IoT systems, for the re-

al-time observation of trees physical and biological

parameters applicable to the monitoring of forests,

New tree monitoring systems: from Industry 4.0 to Nature 4.0

Riccardo Valentini1,3, Luca Belelli Marchesini2,3*, Damiano Gianelle2, Giovanna Sala3, Alexey Yarovslavtsev4,

Viacheslav I. Vasenev3, Simona Castaldi 3,5

Received 31/01/2019- Accepted 3/06/2019- Published online 30/11/2019

Abstract - Recently, Internet of Things (IoT) technologies have grown rapidly and represent now a unique opportunity to improve

our environmental monitoring capabilities at extremely low costs. IoT is a new system of thinking in which objects, animals or people

are equipped with unique identiers and transfer data to a network without requiring human-to-human or human-to-computer inter-

action. IoT has evolved from the convergence of wireless technologies, microelectromechanical systems (MEMS) and the Internet.

The development of these technologies in environmental monitoring domains allows real-time data transmission and numerous low-

cost monitoring points. We have designed a new device, the TreeTalker©, which is capable of measuring water transport in trees,

diametrical growth, spectral characteristics of leaves and microclimatic parameters and transmit data in semi-real time. Here we

introduce the device’s features, provide an example of monitored data from a eld test site and discuss the application of this new

technology to tree monitoring in various contexts, from forest to urban green infrastructures management and ecological research.

Keywords - Internet of Things; tree monitoring; ecophysiology.

R. Valentini1,3, l. Belelli MaRchesini2,3*, D. Gianelle2, G. sala3, a. YaRoVslaVtseV4, V. i. VaseneV3, s. castalDi3,5

New tree monitoring systems: from Industry 4.0 to Nature 4.0

Annals of Silvicultural Research - 43 (2), 2019:

84-88

agro-forestry systems and urban green infrastruc-

tures. This device is designed to be deployed on tree

clusters and transmit data using technologies typi-

cal of the IoT systems, thus providing cost-effective,

semi-real time data from the monitored targets. The

use of TreeTalker devices can support informed de-

cision making related to trees management in differ-

ent spheres from urban settings to natural forests

and it allows the monitoring of trees applied to for-

est research. In this paper, we describe the device,

its measurement capabilities and the network archi-

tecture it makes use of. We also provide an exam-

ple of preliminary results that have been collected

at test sites where TreeTalkers have been deployed

and discuss present and potential ﬁeld of applica-

tions and device developments.

Materials and Methods

The TreeTalker (TT) consists of a microcontrol-

ler with an ATMega 328 processor chip enclosed in a

case (11.5x6.5x6 cm) acquiring signals from a num-

ber of sensors designed for the measurement of var-

iables including: water transport in the xylem of the

trunk (sapﬂow), wood temperature and humidity,

multispectral signature of light transmitted through

the canopy, tree trunk radial growth, accelerations

along a 3D coordinate system used to detect tree

movements, air temperature and relative humidity

which can be additionally complemented by soil

temperature and volumetric water content (SWC).

A TT is typically mounted on trees by means of

a belt tightened around the tree trunk, and powered

by a combination of high-efﬁciency Lithium-ion bat-

teries (3.7 V) and a small solar panel attached on the

battery case (Fig. 1). Depending on enabled meas-

urement types, acquisition frequency and installa-

tion location, the batteries autonomy is expected to

span from 3 weeks to 1 year.

The sapﬂow density is retrieved according to the

Heat Balance Method (Granier 1985) by monitoring

the temperature of two 20 mm long probes insert-

ed into the stem wood at 10 cm distance along the

trunk vertical axis. The probe in the higher position

is heated while the lower one provides the stem

wood reference temperature and is additionally

equipped with a capacitive sensor for wood mois-

ture measurements. A similar technology is used in

a dedicated probe for SWC and temperature meas-

urements. Multispectral measurements of sunlight

are performed across 12 bands covering the visible

and near infra-red spectra and centred at the wave-

lengths of 450, 500, 550, 570, 600, 610, 650, 680, 730,

760, 810 and 860 nm (full-width half-max of 40nm)

by means of a spectrometer with a ﬁeld of view

of 40˚ mounted on top of the TT case. Stem radial

growth is measured by an infra-red pulsed distance

sensor positioned at few centimetres from the tree

trunk’s surface and kept in place by a carbon ﬁbre

stick anchored in the xylem. Any stem radial incre-

ment therefore translates into a reduction of the

distance between the sensor and the targeted tree

trunk’s surface which according to laboratory tests

can be determined with a resolution of not less than

100 μm for a sensor-target distance up to 5 cm. The

TT incorporates an accelerometer providing data

on changes of the device position over time and in-

stant accelerations of the tree trunk where it is in-

stalled. This technology can be conveniently applied

to monitor the root plate tilt with an accuracy of ±

0.01°, as well as the ﬂection and the accelerations

that tree trunks receive under the force of wind for

the evaluation of tree failure risk. A thermo-hygrom-

eter, embedded on the microcontroller, completes

the set of sensors; air exchange through the device

case is allowed by a 0.6 mm wide circular hole cov-

ered with a water vapor permeable membrane.

The TreeTalker features a wireless connection

(using powerful low power chipset LoRa for data

transmission) to a node managed by another mi-

crocontroller (TT-Cloud) serving up to 48 devices in

one cluster (we suggest 20 to avoid data collision)

and data transmission is typically set at hourly fre-

Figure 1 - Tree-Talker installed for the monitoring of a tree and its

power unit (battery case with photovoltaic panel).

R. Valentini1,3, l. Belelli MaRchesini2,3*, D. Gianelle2, G. sala3, a. YaRoVslaVtseV4, V. i. VaseneV3, s. castalDi3,5

New tree monitoring systems: from Industry 4.0 to Nature 4.0

Annals of Silvicultural Research - 43 (2), 2019:

84-88

quency although customizable. The TT-Cloud is in

turn connected to the internet via the GPRS net-

work and sends data to a computer server (Tab. 1).

To date, the performance of TreeTalkers is being

tested at several sites, both in Italy and in Russia,

with distinct characteristics in terms of climate,

land cover/use, topography, exposure, tree species,

age and stand density for the particular purposes of:

(i) evaluating the reliability and operational limits

of the sensors and of the data transmission system;

(ii) estimate the battery autonomy and (iii) compile

a list of recommendations for the set-up of the de-

vices tailored to distinct installation environments.

One of the test sites is in the territory of the Mos-

cow Timiryazev Agricultural Academy (MTAA; co-

ordinates: 55°50’ N; 37°33’E), chosen to deploy the

devices in an urban setting exposed to continental

climate with cold winters (Köppen climate classi-

ﬁcation Dfb). We installed TT devices on 13 street

linden trees (Tilia cordata L.) in front of the MTAA

premises in summer 2018. The installation height

was at about 5 m, in order to prevent vandalism and

the height of the trees reached up to 20 m. A second

test site is in a mixed forest stand in the Umbria re-

gion in Italy (Piegaro forest, coordinates: 42°57’49”N

12°3’31”E, altitude: 430 m a.s.l) with a prevalent cov-

100

125

0.25

0.50

0.75

1.0

1.25

Sep 01 Sep 02 Sep 03 Sep 04

time

Sap flow desnisty l m

-2

-1

VPD, kPa

Figure 2 - Hourly data of sapflow density flux (green line) and vapor

pressure deficit (VPD, blue line) measured over three

days in early September 2018 at the MTAA test site. VPD

was calculated from air temperature and relative humidity

measured within the TT case.

0.00

0.25

0.50

0.75

Sep 01 Sep 15 Oct 01 Oct 15 Nov 01

date

NDVI

Air temperature,C

Figure 3 - Pattern of air temperature (blue line, hourly data) and

NDVI (boxplots, daily data) measured between 1 Septem-

ber and 31 October 2018 capturing the progression of

leaf senescence phase.

Table 1 - Components of the TT devices and their characteristics.

Device Component Description

TT (TreeTalker)

Sap ow Reference and heated temperature probes (±0.1 °C). Thermistors

manufacturer: Murata Electronics. Model: NCU18XH103F6SRB

Stem humidity Capacitive sensor

MicroPCB (20x3x2) mm with copper plates.

Canopy light transmission Spectrometer-12 spectral bands (450, 500, 550, 570, 600, 610,

650, 680, 730, 760, 810, 860 nm)

Full width half max: 20 nm (VIS);40 nm (NIR).

Manufacturer: AMS. Model: AS7262 (Visible range), AS7263 (Near

Infrared range)

Tree trunk radial growth Infra-red distance sensor ( min ±100 μm)

Manufacturer: SHARP. Model: GP2Y0A51SK0F

Tree trunk axis movement Accelerometer (± 0.01°)

Manufacturer: NXP/Freescale. Model: Si7006

Air temperature and humidity Thermohygrometer (±0.1 °C ;

±2 %). Manufacturer: Silicon Labs. Model: MMA8451Q

Flash memory for data storage 16Mbyte

LoRa module for data transmission Transmission 600 m (in urban/rural environment). It can reach >3

km in case line of sight

4 Li-Ion batteries + solar panel 3.7 V

TT Cloud

Modem/router LoRa protocol 868 MHz with external antenna

Modem GPRS

WiFi connection alternative to GPRS if available

Flash memory for data storage 16 Mbyte

4 Li-Ion batteries +solar panel 3.7 V

R. Valentini1,3, l. Belelli MaRchesini2,3*, D. Gianelle2, G. sala3, a. YaRoVslaVtseV4, V. i. VaseneV3, s. castalDi3,5

New tree monitoring systems: from Industry 4.0 to Nature 4.0

Annals of Silvicultural Research - 43 (2), 2019:

84-88

er of Douglas ﬁr (Pseudotsuga menziesii (Mirb.)

Franco), Scotch pine (Pinus sylvestris L.) and, to a

very minor extent, of sessile oak (Quercus petraea

(Mattuschka) Liebl.). A set of 13 Tree-Talkers was

installed at the site in October 2018 and distribut-

ed according to the forest speciﬁc composition.

The devices were positioned at about 1.5 m from

the ground on trees having a stem circumference at

breast height ranging between 93 and 227 cm (mean:

134.4 cm) and a mean canopy height of 18 m.

Results and Discussion

We provide some examples of data being col-

lected in fall 2018 at the Moscow and Piegaro ﬁeld

test sites respectively in order to illustrate the ca-

pabilities of the measuring device in distinct ﬁelds

of application. The ﬁrst set of data was collected in

the period September-October 2018 from a mature

linden tree specimen with a breast height diameter

of 39 cm. The characterization of the stem water

transport variability, at hourly time step, in relation

to the surrounding microclimate for a subset of 3

days is presented in Fig. 2 . Sapﬂow density ﬂux,

retrieved from the application of the Granier tech-

nique, featured maximum values between 50 and

75 l m

-2

-1

. The diel pattern and correlation of the

sapﬂow density ﬂux and the vapor pressure deﬁcit

(VPD) appears well evident (R=0.805; P<0.0001).

The VPD, which combines the temperature and rel-

ative humidity signals measured by the integrated

thermos-hygrometer of the Tree-Talker, represents

the difference between the actual and saturation

water vapor pressure in the air (Allen et al. 1998)

and it acts as the main environmental driver of wa-

ter transpiration.

A second example, concerning the monitoring of

tree phenological dynamics (Fig. 3), illustrates the

declining pattern of the transmitted Normalized Dif-

ference Vegetation Index (NDVI) during the phase

of leaf senescence along with the decreasing trend

of air temperature which is the main driver of leaf

chlorophyll degradation (Soudani et al. 2012, Gill et

al. 2015, Yang et al. 2017).

The monitoring of a Douglas ﬁr tree (dbh: 60 cm;

height: 18 m) at the Piegaro site provided a good ex-

ample of the application of the Sharp sensor to the

estimate of stem radial growth (Fig.4). The obser-

vations allowed the detection of variations in tree

radius size in the order 0.1 mm at daily time scale,

typically associated to the diel cycle of sapﬂow

(Sevanto et al. 2008, Hermann et al. 2015). The radial

growth trend, retrieved by ﬁltering the data with 24

hour time window moving average resulted in 0.15

± 0.08 mm d-1 (mean ± std.dev).

All data were acquired directly from a web serv-

er and no problems of data transmission with the

LoRa protocol of radio communication between the

TT devices and the TT-Cloud were encountered.

The use of IoT solutions with GPRS network to

remote servers and online data processing is sug-

gested in the ﬁeld of trees monitoring. Detailed in-

formation at tree level can be potentially used for an

accurate and temporally frequent assessment of the

provided ecosystem services (e.g. climate regula-

tion, water storage, carbon sequestration, pollutants

removals, etc.) from the scale of tree to forest stand.

Continuous eco-physiological monitoring is cru-

cial for understanding the biological response of

trees to changes in the environmental condition,

however it is generally not performed except for

a limited number of instances limited to scientiﬁc

research purposes. TTs allows the monitoring of

trees in semi-real time and represent a valid tool to

estimate to assess functionality and early detection

of stress responses in trees (water stress, extreme

temperatures, disease/pest attacks) which can be

used for scientiﬁc research but also for decision

making support in the management of forests, ur-

ban green infrastructures, agroforestry systems, or-

chards, etc. In the instance of an urban area, such

data ﬂow can lead to faster and better informed de-

cisions to ensure a safe and healthy environment for

citizens (Talavera et al. 2017).

Apart from the aspect of continuity, the TT de-

vice introduces innovative aspects to the traditional

tree monitoring thanks to the technology of its sen-

sors and their novel ﬁeld of application. Continuous

observation of tree canopy under a rich number of

spectral bands (12) allows extracting information

on changes of the colour of the leaves or defoliation

which may be symptomatic of disrupted tree health.

The TreeTalker allows also the monitoring of tree

trunk diametrical growth with precision of high end

Figure 4 - Stem radial growth of a Douglas fir specimen at the

Piegaro forest site inferred from variations of the sensor

to tree trunk distance. Original hourly data (blue line) and

moving average (n=24; red line) showing the trend of

radial growth.

R. Valentini1,3, l. Belelli MaRchesini2,3*, D. Gianelle2, G. sala3, a. YaRoVslaVtseV4, V. i. VaseneV3, s. castalDi3,5

New tree monitoring systems: from Industry 4.0 to Nature 4.0

Annals of Silvicultural Research - 43 (2), 2019:

84-88

dendrometers (Drewa and Downs 2009) and when

installed at breast height (1.3 m), readings can be

directly compared with traditional dendrometric

data and used for the assessment of tree biomass

and carbon stocks. The detection of a progressive

inclination of trees or deviation from the normal

response under wind load has a great potential of

being applied in the context of an early warning sys-

tem for hazard trees (James and Hallam 2013).

Conclusions

We presented a new device, the TreeTalker©,

which is capable of measuring water transport in

trees, trunk radial growth, spectral characteristics

of the leaves, and microclimatic parameters.

The devices are typically installed in clusters of

20 units and at customizable time intervals transmit

data via radio protocol to a receiving microcontrol-

ler which in turn sends them to a web server using

the GPRS network. Near real time data from a con-

tinuous monitoring system are therefore available

on the internet for visualization and further analysis.

Ongoing tests have so far demonstrated the ca-

pability of the device of successfully monitoring

trees parameters and send data at hourly time step

with an autonomy of not less than 3 weeks, also in

the case high latitude autumnal conditions, as those

encountered at the test site in Moscow city.

The application of Internet of Things technology,

at the base of the TreeTalker, the monitoring of trees

opens new opportunities in the ﬁeld of forest and

green urban infrastructures management as well as

ecophysiological research.

Acknowledgements

We acknowledge the technical support of Dro-

mo Elettronical s.r.l (Italy) and we wish to thank

Syed Wasif Ahmed and Nafeesa Samad from Univer-

sity of Tuscia for their help with Tree-Talkers instal-

lation and data collection at the site of Piegaro. The

experimental activities in Moscow were supported

by the Russian Science Foundation (project n°. 19-

77-30012) while the manuscript preparation was

possible thanks to the “RUDN University program

5-100”

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Full-text available

Jul 2024

El desarrollo de nuevos sensores con tecnologías inalámbricas y la gestión de datos en la nube permiten, en la actualidad, sustituir o complementar fácilmente las evaluaciones ecofisiológicas en masas forestales. Estos sensores facilitan la monitorización de parámetros biofísicos relacionados con variables fisiológicas con una precisión y frecuencia cada vez mayor y un coste cada vez menor. Este capítulo repasa los principios y la aplicación de la sensorización próxima autónoma de la vegetación a través de cuatro bloques: i) el contexto general sobre sensorización ambiental, ii) la descripción de los tipos de colectores de datos, iii) los conceptos y ejemplos de programación y procesado de datos de sensores en entornos forestales, y iv) las aplicaciones a ecosistemas forestales. También se detallan las consideraciones más generales que deben tenerse en cuenta en el diseño del trabajo de campo para estudios ecofisiológicos, destacando los compromisos de diseño (en sentido amplio, no sólo estadístico) y enfatizando las ventajas de una planificación adecuada, así como las diferentes opciones en cuanto a equipos disponibles. Por la especificidad de este libro, el capítulo se orienta a las variables biofísicas de mayor interés en teledetección forestal y a su relación con otras variables estructurales. Por tanto, el objetivo del capítulo es ofrecer información actualizada sobre sensorización forestal como una herramienta de trabajo para todos aquellos interesados en los aspectos más prácticos de la ecofisiología forestal y su relación con la teledetección. Se ofrece, además, información sobre sensorización en estudios de "campo" y sobre las limitaciones o requerimientos que su uso impone en el diseño experimental a diferentes escalas espaciales y temporales en función de las variables que se estudian. Palabras clave: ecofisiología forestal, datos continuos, sensorización, series temporales, integración de datos.

Forest hydrology in Chile: Past, present, and future

Article

Nov 2022
J HYDROL

This paper reviews the current knowledge of hydrological processes in Chilean temperate forests which extend along western South America from latitude 29° S to 56° S. This geographic region includes a diverse range of natural and planted forests and a broad sweep of vegetation, edaphic, topographic, geologic, and climatic settings which create a unique natural laboratory. Many local communities, endangered freshwater ecosystems, and downstream economic activities in Chile rely on water flows from forested catchments. This review aims to (i) provide a comprehensive overview of Chilean forest hydrology, to (ii) review prior research in forest hydrology in Chile, and to (iii) identify knowledge gaps and provide a vision for future research on forest hydrology in Chile. We reviewed the relation between native forests, commercial plantations, and other land uses on water yield and water quality from the plot to the catchment scale. Much of the global understanding of forests and their relationship with the water cycle is in line with the findings of the studies reviewed here. Streamflow from 2 forested catchments increases after timber harvesting, native forests appear to use less water than plantations, and streams draining native forest yield less sediment than streams draining plantations or grassland/shrublands. We identified 20 key knowledge gaps such as forest groundwater systems, soil-plant-atmosphere interactions, native forest hydrology, and the effect of forest management and restoration on hydrology. Also, we found a paucity of research in the northern geographic areas and forest types (35-36° S); most forest hydrology studies in Chile (56%) have been conducted in the southern area (Los Rios Region around 39-40° S). There is limited knowledge of the geology and soils in many forested areas and how surface and groundwater are affected by changes in land cover. There is an opportunity to advance our understanding using process-based investigations linking field studies and modeling. Through the establishment of a forest hydrology science "society" to coordinate efforts, regional and national-scale land use planning might be supported. Our review ends with a vision to advance a cross-scale collaborative effort to use new nationwide catchment-scale networks Long-term Ecosystem Research (LTER) sites, to promote common and complementary techniques in these studies, and to conduct transdisciplinary research to advance sound and integrated planning of forest lands in Chile.

Calibration of a new Transient Thermal Dissipation based IoT-Sensor for xylem sap flow density measurements for three different temperate tree species

Article

Full-text available

Apr 2025
TREE PHYSIOL

Measuring xylem sap flow is crucial for calculating water use in trees and forests, but remote measurements are challenging, especially regarding power supply. The Transient Thermal Dissipation (TTD) system addresses these challenges by being power-efficient and robust. This study assesses the TreeTalker© system (version TT+), a newly developed battery-powered, IoT-based measurement system with new probes in terms of structure and material compared to previous versions. To calibrate the system, different flow indices (Ki) were derived for various heating/cooling cycles at several sap flow densities (SFD) using an artificial hydraulic column made of sawdust. To provide a calibration equation for different species, freshly cut stem segments with three distinct xylem structures of temperate trees were used under controlled conditions: Quercus robur L. (oak, ring-porous), Abies alba MILL. (fir, coniferous) and Fagus sylvatica L. (beech, diffuse-porous). A linear model best described the relationship between Ki and SFD for sawdust and oak, while a power function suited fir and beech. Compared to literature, the regression steepness increased with the conduit size. Using the sawdust equation for oak resulted in a 55 ± 3% underestimation of SFD. For fir and beech, using the sawdust equation overestimated daily water use by 149 ± 116% and 71 ± 41%, respectively. A multi-media equation across all tested media reduced the underestimation in oak to 19 ± 3% but increase the overestimation for fir and beech compared to the sawdust equation to 352 ± 210% and 209 ± 75%, respectively. For more accurate estimation of absolute values, species-specific calibration equations are recommended assess SFD using the TTD method. However, there appears to be a dependency when comparing different linear calibration equations with the corresponding conduit sizes of the tree species.

Differing seasonal trends in water use and water status between park and street trees

Article

Full-text available

Mar 2025

Ecophysiology of Mediterranean Chestnut (Castanea sativa Mill.) Forests: Effects of Pruning Studied through an Advanced IoT System

Article

Full-text available

Sep 2024

Chestnut (Castanea sativa Mill.) forests in the Mediterranean region are facing increasing abandonment due to a combination of factors, ranging from climate change to socioeconomic issues. The recovery of chestnut ecosystems and their preservation and valorization are key to ensuring the supply of the wide spectrum of ecosystem services they provide and to preventing detrimental environmental shifts. The study’s objective was to provide evidence on the effects of different management options on the ecophysiology of chestnut forests, with diverse pruning intensities (low, medium, and high intensity versus no pruning) tested in an abandoned chestnut stand in central Italy with the aim of recovering and rehabilitating it for fruit production. Innovative Internet of Things (IoT) ‘Tree Talker’ devices were installed on single trees to continuously monitor and measure ecophysiological (i.e., water transport, net primary productivity, foliage development) and microclimatic parameters. Results show a reduction in water use in trees subjected to medium- and high-intensity pruning treatments, along with a decrease in the carbon sequestration function. However, interestingly, the results highlight that trees regain their usual sap flow and carbon sink activity at the end of the first post-pruning growing season and fully realign during the following year, as also confirmed by the NDVI values. As such, this paper demonstrates the efficacy of recovering and managing abandoned chestnut forests, and the initial setback in carbon sequestration resulting from pruning is rapidly remedied with the advantage of reviving trees for fruit production. Additionally, the reduced water demand induced by pruning could represent a promising adaptation strategy to climate change, bolstering the resilience of chestnut trees to prolonged and intensified drought periods, which are projected to increase under future climate scenarios, particularly in the Mediterranean region.

Continuous Plant-Based and Remote Sensing for Determination of Fruit Tree Water Status

Article

Full-text available

May 2024

Climate change poses significant challenges to agricultural productivity, making the efficient management of water resources essential for sustainable crop production. The assessment of plant water status is crucial for understanding plant physiological responses to water stress and optimizing water management practices in agriculture. Proximal and remote sensing techniques have emerged as powerful tools for the non-destructive, efficient, and spatially extensive monitoring of plant water status. This review aims to examine the recent advancements in proximal and remote sensing methodologies utilized for assessing the water status, consumption, and irrigation needs of fruit tree crops. Several proximal sensing tools have proved useful in the continuous estimation of tree water status but have strong limitations in terms of spatial variability. On the contrary, remote sensing technologies, although less precise in terms of water status estimates, can easily cover from medium to large areas with drone or satellite images. The integration of proximal and remote sensing would definitely improve plant water status assessment, resulting in higher accuracy by integrating temporal and spatial scales. This paper consists of three parts: the first part covers current plant-based proximal sensing tools, the second part covers remote sensing techniques, and the third part includes an update on the on the combined use of the two methodologies.

Impact of thinning on leaf economics, plant hydraulics, and growth dynamics

Article

Full-text available

Apr 2024
FOREST ECOL MANAG

Integrating climate change concerns into forest management strategies remains challenging. Among management strategies, thinning has been proven to alter major components underlying the carbon and water cycles over the short term. However, the functional adaptability of managed forests to cope with long-term drought remains unclear. This study aims to quantify the influence of thinning on key plant functional traits for two pine species, and their impacts on the fundamental processes of tree growth and transpiration. We conducted an experimental silvicultural trial with varying thinning intensities in two Pinus sylvestris and Pinus nigra plantations with the following specific objectives: i) to assess the impact of thinning on major traits involved in the leaf economic spectrum (LES), and hydraulic relations, and ii) to understand which of these traits reflect fundamental aspects of plant growth and transpiration, and their relations with environment. We used a combination of dendrochronological (basal area increment, BAI), sapflow (Fd), and tree ring isotope (δ13C) data, along with key functional and physiological traits including photosynthesis (A), leaf mass area (LMA), Huber value (Hv), sapwood density (Wd), and predawn to midday water potential (Ψpd, Ψmd). Our results revealed species-specific responses, with P. nigra exhibiting a conservative growth strategy, whereas P. sylvestris displayed increased growth after thinning. Despite thinning influenced both BAI and wood δ13C with notable species-dependent variations, we evidenced a general convergence in the relationships between LES traits and Hv across species, treatments and seasons (p <0.01). BAI responses to thinning translated into predictable changes in key hydraulic traits and adaptive changes in physiological performance. For instance, BAI was inversely related to LMA and Hv. Consistent with LES, variations in LMA influenced A. In turn, seasonal variations in LMA scaled negatively with Ψpd, and Ψmd (p <0.01). Such a functional adaptation suggests that thinning promotes growth while favouring forest resilience in the long term. This study provides practical implications for the implementation of a trait-based approach into silvicultural frameworks and anticipating the consequences of climate change for managed forest ecosystems.

Development and Application of an Automated System for Early Detection of Stress and Damage in Poplar Clone Plantations Using Eco-Physiological Sensors and IoT

Conference Paper

Nov 2023

Knowledge discovery for enabling smart Internet of Things: A survey

Article

Full-text available

Jul 2018

The use of knowledge discovery on the Internet of Things (IoT) and its allied domains is undeniably one of the most indispensable ones, which results in optimized placement architectures, efficient routing protocols, device energy savings, and enhanced security measures for the implementation. The absence of knowledge discovery in IoT results in just an implementation of large‐scale sensor networks, which generates a huge amount of data, and which needs, an often under‐optimized, processing for actionable outputs. In this survey, we explore various domains of IoT for which knowledge discovery is inseparable from the application, and show how it benefits the overall implementation of the IoT architecture. This article is categorized under: • Fundamental Concepts of Data and Knowledge > Knowledge Representation • Technologies > Machine Learning • Application Areas > Internet and Web‐Based Applications • Algorithmic Development > Spatial and Temporal Data Mining

Internet of Things based Wireless Plant Sensor for Smart Farming

Article

Full-text available

May 2018

About 10% of the world’s workforce is directly dependent on agriculture for income and about 99% of food consumed by humans comes from farming. Agriculture is highly climate dependent and with global warming and rapidly changing weather it has become necessary to closely monitor the environment of growing crops for maximizing output as well as increasing food security while minimizing resource usage. In this study, we developed a low cost system which will monitor the temperature, humidity, light intensity and soil moisture of crops and send it to an online server for storage and analysis, based on this data the system can control actuators to control the growth parameters. The three tier system architecture consists of sensors and actuators on the lower level followed by an 8-bit AVR microcontroller which is used for data acquisition and processing topped by an ESP8266 Wi-Fi module which communicates with the internet server. The system uses relay to control actuators such as pumps to irrigate the fields; online weather data is used to optimize the irrigation cycles. The prototyped system was subject to several tests, the experimental results express the systems reliability and accuracy which accentuate its feasibility in real-world applications. © 2018 Institute of Advanced Engineering and Science. All rights reserved.

Seasonal variations of leaf and canopy properties tracked by ground-based NDVI imagery in a temperate forest

Article

Full-text available

Dec 2017

Changes in plant phenology affect the carbon flux of terrestrial forest ecosystems due to the link between the growing season length and vegetation productivity. Digital camera imagery, which can be acquired frequently, has been used to monitor seasonal and annual changes in forest canopy phenology and track critical phenological events. However, quantitative assessment of the structural and biochemical controls of the phenological patterns in camera images has rarely been done. In this study, we used an NDVI (Normalized Difference Vegetation Index) camera to monitor daily variations of vegetation reflectance at visible and near-infrared (NIR) bands with high spatial and temporal resolutions, and found that the infrared camera based NDVI (camera-NDVI) agreed well with the leaf expansion process that was measured by independent manual observations at Harvard Forest, Massachusetts, USA. We also measured the seasonality of canopy structural (leaf area index, LAI) and biochemical properties (leaf chlorophyll and nitrogen content). We found significant linear relationships between camera-NDVI and leaf chlorophyll concentration, and between camera-NDVI and leaf nitrogen content, though weaker relationships between camera-NDVI and LAI. Therefore, we recommend ground-based camera-NDVI as a powerful tool for long-term, near surface observations to monitor canopy development and to estimate leaf chlorophyll, nitrogen status, and LAI.

The internet of things - wireless sensor networks and their application to forestry

Article

Full-text available

Feb 2017

Small wireless sensor networks (WSNs) have the potential to change the way forests are managed in the future. Already used widely in agricultural and horticultural situations to monitor and control production, what basis do they have as a tool for the modern forest manager? We propose that WSNs could enable a transformation in the way forests are managed in future, by collecting and relaying key management data in real time, as well as helping to better understand complex relationships within forest ecosystems. However, forested environments pose some challenges to deployment, such as reduced signals from vegetation, loss of connectivity and the scale-up factors. http://www.nzjf.org.nz/abstract.php?volume_issue=j61_4&first_page=37

Une nouvelle methode pour la mesure dy flux de seve brute dans le trons des arbres

Article

Full-text available

Jan 1985

A. Granier

La méthode décrite dans cet article utilise un capteur thermique composé de deux sondes insérées radialement dans le bois d’aubier du tronc. Une de ces sondes est chauffée à puissance constante, l’autre sert de référence de température. Une équation simple permet de calculer le flux de sève en fonction de la différence de température entre les deux éléments. Un étalonnage a été effectué sur des échantillons de tronc de différentes essences. Le faible coût et la sensibilité de ce système doivent permettre d’aborder la mesure quantitative de la transpiration et de sa variabilité en forêt.

A complexity view of Industry 4.0

Article

Full-text available

Jun 2016

This article is focused on the importance and influence of Industry 4.0 and consequently the Internet-connected technologies for the creation of value added for organizations and society. The contribution of the article is mainly conceptual. With the development of the Internet, the Internet of things that is central to the new industrial revolution has led to ?Industry 4.0.? The aim of this article is to synthesize the known theory and practices of Industry 4.0, and to investigate the changes that will result from Industry 4.0 and with the development of the Internet of things.

Changes in autumn senescence in northern hemisphere deciduous trees: A meta-analysis of autumn phenology studies

Article

Full-text available

May 2015
ANN BOT-LONDON

Background and Aims Many individual studies have shown that the timing of leaf senescence in boreal and temperate deciduous forests in the northern hemisphere is influenced by rising temperatures, but there is limited consensus on the magnitude, direction and spatial extent of this relationship. Methods A meta-analysis was conducted of published studies from the peer-reviewed literature that reported autumn senescence dates for deciduous trees in the northern hemisphere, encompassing 64 publications with observations ranging from 1931 to 2010. Key Results Among the meteorological measurements examined, October temperatures were the strongest predictors of date of senescence, followed by cooling degree-days, latitude, photoperiod and, lastly, total monthly precipitation, although the strength of the relationships differed between high- and low-latitude sites. Autumn leaf senescence has been significantly more delayed at low (25° to 49°N) than high (50° to 70°N) latitudes across the northern hemisphere, with senescence across high-latitude sites more sensitive to the effects of photoperiod and low-latitude sites more sensitive to the effects of temperature. Delays in leaf senescence over time were stronger in North America compared with Europe and Asia. Conclusions The results indicate that leaf senescence has been delayed over time and in response to temperature, although low-latitude sites show significantly stronger delays in senescence over time than high-latitude sites. While temperature alone may be a reasonable predictor of the date of leaf senescence when examining a broad suite of sites, it is important to consider that temperature-induced changes in senescence at high-latitude sites are likely to be constrained by the influence of photoperiod. Ecosystem-level differences in the mechanisms that control the timing of leaf senescence may affect both plant community interactions and ecosystem carbon storage as global temperatures increase over the next century.

Review of IoT applications in agro-industrial and environmental fields

Article

Sep 2017
COMPUT ELECTRON AGR

This paper reviews agro-industrial and environmental applications that are using Internet of Things (IoT). It is motivated by the need to identify application areas, trends, architectures and open challenges in these two fields. The underlying survey was developed following a systematic literature review using academic documents written in English and published in peer-reviewed venues from 2006 to 2016. Selected references were clustered into four application domains corresponding to: monitoring, control, logistics, and prediction. Implementation-specific details from each selected reference were compiled to create usage distributions of sensors, actuators, power sources, edge computing modules, communication technologies, storage solutions, and visualization strategies. Finally, the results from the review were compiled into an IoT architecture that represents a wide range of current solutions in agro-industrial and environmental fields.

Stability of urban trees in high winds

Article

Feb 2013

Ken James

The stability of trees in storms and high winds was assessed with newly developed tilt instruments that measure the structural properties of tree root plates and their anchorage strength in the ground. Tree root plates flex slightly in the ground when strong winds blow and the tilt instruments measure this flexure continuously. Tilt accuracy of 0.01° was measured at 20 samples per second, which is sufficient to record the dynamic response of the tree in high winds. The instrument has battery power for up to 20 days recording and is simply connected to a computer via a USB cable. Five Norfolk Island pines (Araucaria heterophylla) at Burnie, Tasmania were monitored during a period of high winds. Each tree had one tilt sensor attached to the trunk at ground level and another approximately 3 m above the ground. Tilt data during high winds for the five trees are presented. Tree 5 recorded maximum tilt of 0.40°, which was higher than nearby trees (0.10–0.15°) but is still within acceptable limits that are considered stable. The results indicate that Tree 5 has re-established a root system after previous construction damage and has now stabilised. It is planned to remove the supporting cables and use the tilt sensors annually to monitor the stability of trees.

Ground-based Network of NDVI measurements for tracking temporal dynamics of canopy structure and vegetation phenology in different biomes

Article