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Arthropod biomass increase in spring correlates with NDVI in grassland habitat

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Data from remote sensing are often used as proxies to quantify biological processes, especially at large geographical scales. The normalized difference vegetation index (NDVI) is the most frequently used proxy for primary productivity. Assuming a direct, positive interrelation between primary and secondary production in terrestrial habitats, NDVI is often used to predict food availability for higher trophic levels. However, the relationship between NDVI and arthropod biomass has rarely been tested. In this study, we analyzed extensive datasets of arthropod communities from semi-natural grasslands in central Europe to test the relationship between arthropod biomass of consumer trophic levels ("herbivores," "mixed," and "carnivores") in grassland communities and NDVI during the spring season. We found that arthropod biomass generally increased with NDVI. The same positive relationship between biomass and NDVI was observed for each individual trophic level. Cross-correlation analyses did not show statistically significant lags between the NDVI and biomass of herbivores and carnivores. All in all, our study provides correlational evidence for the positive relation of primary and secondary productivity in temperate terrestrial habitats during spring. Moreover, it supports the applicability of NDVI data as a suitable habitat-specific proxy for the food availability of insectivores during spring.
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ORIGINAL PAPER
Arthropod biomass increase in spring correlates with NDVI
in grassland habitat
Mario Fernández-Tizón
1,2
&Tamara Emmenegger
1
&Jörg Perner
3
&Steffen Hahn
1
Received: 30 April 2020 /Revised: 7 September 2020 /Accepted: 14 September 2020
#Springer-Verlag GmbH Germany, part of Springer Nature 2020
Abstract
Data from remote sensing are often used as proxies to quantify biological processes, especially at large geographical scales. The
normalized difference vegetation index (NDVI) is the most frequently used proxy for primary productivity. Assuming a direct,
positive interrelation between primary and secondaryproductioninterrestrial habitats, NDVI is often used to predict food availability
for higher trophic levels. However, the relationship between NDVI and arthropod biomass has rarely been tested. In this study, we
analyzed extensive datasets of arthropod communities from semi-natural grasslands in central Europe to test the relationship between
arthropod biomass of consumer trophic levels (herbivores,”“mixed,and carnivores) in grassland communities and NDVI during
the spring season. We found that arthropod biomass generally increased with NDVI. The same positive relationship between biomass
and NDVI was observed for each individual trophic level. Cross-correlation analyses did not show statistically significant lags
between the NDVI and biomass of herbivores and carnivores. All in all, our study provides correlational evidence for the positive
relation of primary and secondary productivity in temperate terrestrial habitats during spring. Moreover, it supports the applicability of
NDVI data as a suitable habitat-specific proxy for the food availability of insectivores during spring.
Keywords Primary productivity .Secondary productivity .Proxy .Food abundance .Insects .Remote sensing
Introduction
The availability of nutritional resources can critically influ-
ence community composition and species richness
(Mittelbach et al. 2001; Ribas et al. 2003). Animals in season-
al habitats must deal with temporal variation in resource avail-
abilities caused by periodic changes in vegetation structure
(Stinson and Brown 1983) and habitat quality (Wiegand
et al. 2008). However, estimating resource availability is often
difficult to achieve, especially when large and/or remote areas
should be sampled. Thus, ecologists frequently use proxies
derived from remotely sensed data (Pettorelli et al. 2011;
Stephens et al. 2015). Their application requires knowledge
about the underlying relationship between the measured and
the predicted traits. Such interrelation is relatively easy to
establish if these traits are directly linked, as occurs between
marine primary productivity and phytoplankton abundance
(Marshall and Nesius 1996) or primary productivity and plant
biomass in terrestrial ecosystems (Scurlock et al. 2002).
However, approximations encompassing multiple trophic
levels are harder to evaluate.
In ecology, a frequently used indicator for resource approx-
imations is the normalized difference vegetation index
(NDVI), a measure of primary productivity used for many
years in remote sensing. NDVI distinguishes the reflectance
properties of the vegetation (NIR-Red)/(NIR + Red), with
NIR representing the near-infrared and red the visible red light
reflected by the surface (Myneni et al. 1995). Nowadays,
NDVI data are globally available (e.g., www.star.nesdis.
noaa.gov). The temporal and spatial resolutions of these data
have improved over time and are, therefore, ideal for the
analysis of vegetation dynamics at large scales.
Communicated by: Matthias Waltert
Electronic supplementary material The online version of this article
(https://doi.org/10.1007/s00114-020-01698-7) contains supplementary
material, which is available to authorized users.
*Mario Fernández-Tizón
mario.fdez.tizon@gmail.com
1
Department of Bird Migration, Swiss Ornithological Institute, CH
6204 Sempach, Switzerland
2
Department of Biology, Geology, Physics and Inorganic Chemistry,
University Rey Juan Carlos, Móstoles, Spain
3
U.A.S. Umwelt- und Agrarstudien GmbH, 07743 Jena, Germany
https://doi.org/10.1007/s00114-020-01698-7
/ Published online: 24 September 2020
The Science of Nature (2020) 107: 42
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
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For example, the loss of area of 'short vegetation' appears detrimental, although recent gains in this respect have favoured the bird in the Chornobyl Exclusion Zone and around, where Landsat images show the change from a previously vibrant agricultural and forestry economy, when crops have been replaced by grasslands. Threats posed to the roller by habitat and land use change are also likely to be compounded by the effects of global climate change. In summary, we suggest climate change, in particular velocity, have been responsible for shaping the contemporary home range of the European roller in Ukraine and perhaps beyond. key words Coracias garrulus, species distribution modelling, ecological niche, climate change, velocity of climate change. cite as Shupova, T., V. Tytar. 2022. Long-term monitoring of the European roller (Coracias garrulus) in Ukraine: is climate behind the changes? GEO&BIO, 23: 154-171. Резюме. 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Ми застосували підхід, заснований на принципах моделювання поширення видів (SDM), також відомий як «моделювання екологічної ніші», для ретроспективного вивчення змін ареалу сиворакши протягом історичного часу по всій України та отримання просторових прогнозів екологічно придатних для виду територій як за умов поточного клімату, так і минулого клімату, та впливу низки факторів, які за припущенням мають важливе значення для перебування сиворакши та сприяють забезпеченню достатньої бази для живлення птахів. Моделі були створені для трьох ча-сових інтервалів (до) з використанням відповідних кліматичних даних. Моделі показують скорочення екологічно придатних для птахів територій з 86 до 44%. Було розгля-нуто кілька факторів, які могли сприяти погіршенню ситуації для виду в Україні. Наприклад, втра-та площі «низькорослої рослинності» по країні є негативним фактором. Лише у Чорнобильській зоні відчуження та поблизу неї цей процес, як показують знімки Landsat, є зворотній, що сприяло птахам. Загрози, пов'язані зі зміною середовища існування та землекористування, можуть також посилюватися впливом глобальної зміни клімату. Підводячи підсумок, ми припускаємо, що зміна клімату, зокрема її швидкість, спричинила формування сучасного ареалу сиворакші в Україні та, можливо, за її межами. Ключові слова: Coracias garrulus, моделювання поширення видів, екологічна ніші, зміна клімату, швидкість кліматичних змін. Адреса для зв'язку: Володимир Титар; Інститут зоології ім. І. І. Шмальгаузена НАН України; вул. Бог-дана Хмельницького, 15, Київ, 01601 Ukraine;
... In line with previous studies, we assumed that visually restricted and more three-dimensional (i.e., lusher and greener) habitats are structurally more complex, as animals living here will need to process and store more environmental information, while filtering out relevant cues from irrelevant background noise (Safi and Dechmann 2005;Powell and Leal 2014;Calisi et al. 2017;Steck and Snell-Rood 2018). The NDVI is an index of primary productivity (Pettorelli et al. 2011); higher NDVI values correspond to greener, healthier vegetation and higher plant biomass (Lafage et al. 2014) and have also been linked to arthropod abundance (Roiz et al. 2015;Sweet et al. 2015;Fernandez-Tizon et al. 2020). It can thus be used as an indicator of both resource availability (Pettorelli et al. 2011) and habitat complexity (Lassau et al. 2005;Miranda et al. 2018). ...
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