How Does Sun-Induced Chlorophyll Fluorescence Reflect Wetland Ecosystem Health?

濕(shī)地作(zuò)為地(dì)球(qiú)上重要的生(shēng)態(tài)係統，具有調節(jié)氣候，保護(hù)生物多樣(yàng)性等多種(zhǒng)功能。然(rán)而(ér)，濕地(dì)生態係統極(jí)易(yì)受到自(zì)然(rán)和(hé)人(rén)為(wéi)因(yīn)素的影響(xiǎng)，對其進(jìn)行有效(xiào)監測(cè)至關(guān)重(zhòng)要(yào)。

近(jìn)年來，日光(guāng)誘導(dǎo)葉綠素(sù)熒(yíng)光（SIF）作(zuò)為一(yī)種新興(xīng)的遙(yáo)感技(jì)術，為(wéi)濕地監(jiān)測提供了(liǎo)新(xīn)的(dí)視角。SIF在濕地監測中具(jù)有多(duō)種應用，主要包(bāo)括以(yǐ)下(xià)幾個(gè)方(fāng)麵：

As a vital ecosystem on Earth, wetlands serve multiple functions such as climate regulation and biodiversity conservation. However, wetland ecosystems are highly susceptible to both natural and anthropogenic influences, making effective monitoring essential.

In recent years, Sun-Induced Chlorophyll Fluorescence (SIF) has emerged as a novel remote sensing technology that offers new perspectives for wetland monitoring. SIF has several key applications in this context, including the following:

1. 濕地植被(bèi)生(shēng)產(chǎn)力評估(gū) / Assessment of Wetland Vegetation Productivity

SIF與植被(bèi)的總初級生(shēng)產(chǎn)力（GPP）具有(yǒu)很強(qiáng)的(dí)相關(guān)性。通(tōng)過(guò)監測SIF，可(kě)以估(gū)算濕地植被的光合速率和(hé)碳(tàn)匯能力(lì)。例如，在潮汐影響(xiǎng)的(dí)濱海(hǎi)鹽沼中，SIF可以(yǐ)用於監(jiān)測(cè)總初(chū)級生(shēng)產(chǎn)力(lì)和蒸散。最新研(yán)究(jiū)顯(xiǎn)示，SIF有潛力成為量(liáng)化沿(yán)海濕(shī)地生(shēng)態係統(tǒng)中(zhōng)碳和水循(xún)環(huán)的一種新方法。

SIF is strongly correlated with Gross Primary Productivity (GPP) in vegetation. By monitoring SIF, it is possible to estimate photosynthetic rates and carbon sequestration capacity of wetland plants. For instance, in coastal salt marshes influenced by tides, SIF can be used to monitor GPP and evapotranspiration. Recent studies suggest that SIF has the potential to become a new method for quantifying carbon and water cycles in coastal wetland ecosystems.

一項(xiàng)研(yán)究對(duì)上海(hǎi)九端(duān)沙濕地自然保護區(qū)進行了觀測和研究

A study conducted observations and research in the Shanghai Jiuduansha Wetland Nature Reserve

觀(guān)測和模(mó)擬(nǐ)的 (a)冠(guān)層(céng)太(tài)陽誘導(dǎo)葉綠素熒(yíng)光(guāng)在(zài)760nm處(chǔ)的每日變化(huà)（SIF760），(b)2019 年(nián)初級生產總生產率（GPP）和 (c)蒸散量(liáng)（ET）

Monitoring and simulating the daily variations of (a) canopy sun-induced chlorophyll fluorescence at 760 nm (SIF760), (b) gross primary productivity (GPP), and (c) evapotranspiration (ET) for the year 2019.

2.濕(shī)地(dì)生態係統健康(kāng)監(jiān)測(cè) / Monitoring Wetland Ecosystem Health

濕(shī)地(dì)生(shēng)態係(xì)統對(duì)環境變化非(fēi)常敏感(gǎn)，易(yì)受到幹旱，汙(wū)染，水位變化等(děng)因素(sù)的(dí)影(yǐng)響。SIF對這(zhè)些(xiē)環(huán)境脅迫(pò)具(jù)有(yǒu)高靈(líng)敏度，能夠(gòu)反(fǎn)映(yìng)濕地植(zhí)被(bèi)的(dí)健康狀(zhuàng)況和適應能(néng)力(lì)。例如(rú)，幹旱會導(dǎo)致(zhì)植被光(guāng)合(hé)效率(shuài)下降，SIF信號也會相應減(jiǎn)弱(ruò)。通(tōng)過監(jiān)測SIF的變(biàn)化，可以早期(qī)預(yù)警(jǐng)濕地(dì)生(shēng)態係(xì)統的(dí)退(tuì)化(huà)風(fēng)險。

Wetland ecosystems are highly sensitive to environmental changes such as drought, pollution, and water level fluctuations. SIF is highly responsive to these environmental stresses and can reflect the health status and adaptability of wetland vegetation. For example, drought leads to reduced photosynthetic efficiency, which is accompanied by a decrease in SIF signals. Monitoring changes in SIF can provide early warnings of degradation risks in wetland ecosystems.

3.濕地恢(huī)復評估與管(guǎn)理(lǐ) / Evaluation and Management of Wetland Restoration

在(zài)濕(shī)地(dì)生(shēng)態恢復過(guò)程中，SIF可以(yǐ)作為(wéi)一(yī)種重要(yào)的評估(gū)工(gōng)具。通(tōng)過監測恢(huī)復區域的SIF信號，可以快(kuài)速(sù)評估植被的(dí)光合(hé)效(xiào)能和覆蓋(gài)情(qíng)況(kuàng)，了解(jiě)恢復措施(shī)的效果。例如(rú)，在(zài)植(zhí)被重建區域，SIF可以(yǐ)用於評(píng)估新種植植(zhí)物的生長狀(zhuàng)態(tài)和(hé)光合(hé)能力。

During ecological restoration of wetlands, SIF can serve as an important evaluation tool. By monitoring SIF signals in restored areas, it is possible to quickly assess vegetation photosynthetic performance and coverage, thereby evaluating the effectiveness of restoration measures. For instance, in revegetated zones, SIF can be used to monitor the growth status and photosynthetic capacity of newly planted vegetation.

日(rì)光(guāng)誘(yòu)導(dǎo)葉綠素熒(yíng)光(guāng)（SIF）監測具有多(duō)個(gè)顯著特點：

它(tā)能夠(gòu)直接(jiē)反映(yìng)光合作用，因為(wéi)SIF直(zhí)接來(lái)源於葉綠素的光化學(xué)反應，從而(ér)更準確(què)地(dì)表(biǎo)征植物的(dí)光合效率(shuài)與碳(tàn)吸收能(néng)力。與此同(tóng)時，SIF對環境(jìng)脅迫非(fēi)常敏(mǐn)感(gǎn)，可早(zǎo)期響(xiǎng)應(yīng)水(shuǐ)分(fēn)，溫(wēn)度(dù)及養分等環(huán)境(jìng)因(yīn)素的變(biàn)化，及(jí)時反(fǎn)映植被所受的脅迫(pò)狀(zhuàng)態。此外(wài)，該(gāi)監測(cè)方(fāng)法(fǎ)屬於非接觸(chù)式測量，不(bù)會(huì)對植(zhí)被造成(chéng)任何損傷(shāng)，具(jù)有(yǒu)非破壞性的優(yōu)勢。在可擴展(zhǎn)性(xìng)方(fāng)麵，SIF技(jì)術易(yì)於與遙感(gǎn)技(jì)術結合(hé)，支持(chí)大範圍(wéi)，長時間序列的連續監(jiān)測。

Sun-Induced Chlorophyll Fluorescence (SIF) monitoring exhibits several notable characteristics:

It directly reflects photosynthesis, as S originates from the photochemical reactions of chlorophyll, enabling more accurate characterization of plant photosynthetic efficiency and carbon uptake capacity. At the same time, SIF is highly sensitive to environmental stresses and can provide an early response to changes in factors such as water availability, temperature, and nutrient conditions, promptly reflecting the stress status of vegetation. Furthermore, this monitoring method is non-contact and non-destructive, causing no harm to plants. In terms of scalability, SIF technology can be easily integrated with remote sensing techniques, supporting large-scale and long-term continuous monitoring.

這(zhè)些監測(cè)任(rèn)務(wù)可通過多種技(jì)術(shù)手段(duàn)實現，包(bāo)括葉(yè)片測量，塔(tǎ)基測量，航空(kōng)遙(yáo)感(gǎn)及衛(wèi)星(xīng)遙(yáo)感(gǎn)等；愛博能推(tuī)出的日光誘導(dǎo)葉綠(lǜ)素熒光(guāng)監測係統，就(jiù)提(tí)供(gōng)了在(zài)綫(xiàn)式和(hé)無(wú)人(rén)機載(zǎi)係統(tǒng)，覆蓋從地麵(miàn)到(dào)低(dī)空(kōng)的不(bù)同測量尺度(dù)。該係統(tǒng)適用於(yú)濕(shī)地生態監測，其(qí)優勢在(zài)於能夠高效(xiào)，精(jīng)準(zhǔn)地獲取(qǔ)大範圍濕地(dì)植(zhí)被(bèi)的(dí)生理(lǐ)狀態和脅(xié)迫響應(yīng)，幫助(zhù)客(kè)戶(hù)實(shí)時掌握生(shēng)態(tài)係(xì)統(tǒng)健(jiàn)康動態(tài)，為(wéi)濕地保(bǎo)護，恢復與管(guǎn)理(lǐ)提(tí)供關(guān)鍵(jiàn)的(dí)數(shù)據支(zhī)撐和決(jué)策依(yī)據(jù)。

These monitoring tasks can be achieved through various technical means, including leaf-level measurements, tower-based platforms, aerial remote sensing, and satellite remote sensing.The Sun-Induced Chlorophyll Fluorescence Monitoring System launched by ExponentSci includes both online and UAV-borne systems, covering measurement scales from the ground to low-altitude airspace. This system is well-suited for wetland ecological monitoring due to its ability to efficiently and accurately capture the physiological status and stress responses of vegetation across large wetland areas. It enables clients to monitor ecosystem health dynamics in real time and provides critical data support and decision-making basis for wetland conservation, restoration, and management.

案(àn)例來(lái)源 / Source：

Lai, J., & Huang, Y. (2024). Potential of Solar-Induced Chlorophyll Fluorescence for Monitoring Gross Primary Productivity and Evapotranspiration in Tidally-Influenced Coastal Salt Marshes. Remote Sensing, 16(24), 4636.