Widespread decline in Central European plant diversity across six decades

Abstract

Based on plant occurrence data covering all parts of Germany, we investigated changes in the distribution of 2136 plant species between 1960 and 2017. We analyzed 29 million occurrence records over an area of ~350,000 km2 on a 5 × 5 km grid using temporal and spatiotemporal models and accounting for sampling bias. Since the 1960s, more than 70% of investigated plant species showed declines in nationwide occurrence. Archaeophytes (species introduced before 1492) most strongly declined but also native plant species experienced severe declines. In contrast, neophytes (species introduced after 1492) increased in their nationwide occurrence but not homogeneously throughout the country. Our analysis suggests that the strongest declines in native species already happened in the 1960s–1980s, a time frame in which often few data exist. Increases in neophytic species were strongest in the 1990s and 2010s. Overall, the increase in neophytes did not compensate for the loss of other species, resulting in a decrease in mean grid cell species richness of −1.9% per decade. The decline in plant biodiversity is a widespread phenomenon occurring in different habitats and geographic regions. It is likely that this decline has major repercussions on ecosystem functioning and overall biodiversity, potentially with cascading effects across trophic levels. The approach used in this study is transferable to other large‐scale trend analyses using heterogeneous occurrence data.

Phytosociological Analysis of Natural and Artificial Pine Forests of the Class Vaccinio-Piceetea Br.-Bl. in Br.-Bl. et al. 1939 in the Sudetes and Their Foreland (Bohemian Massif, Central Europe)

“…Their high share in forest plantations creates a serious risk of transition to native forest communities in the closest vicinity, as previously reported from many forests of tropical [81] and subtropical zones [84]. [72,86]. It should be emphasized that the majority of the analyzed patches are located within larger forest complexes, and the Polish rules of forest management do not require additional fertilization of plantations established in such areas.…”

Crowd‐sourced plant occurrence data provide a reliable description of macroecological gradients

“…For instance, Mahecha and Schmidtlein (2008) reported sampling biases in Florkart due to inaccurate naming conventions in particular in times where Germany was politically divided. Recently, Eichenberg et al (2020) reported that, with the exception of neophytes, many species groups have declined in Germany over the past decades. Their study is mainly based on Florkart data and reports a negative trends in species richness of −0.19 [% year −1 ] after correcting for multiple potential taxonomic and sampling issues.…”

“…The known data artefacts and species range shifts have been mostly reported for individual species, i.e. singular dimensions in the high‐dimensional binary vector space (Eichenberg et al 2020). As we have shown here, the few underlying dimensions are related to gradients in climate conditions and soil properties along which species niches are oriented.…”

Floral Cues of Non-host Plants Attract Oligolectic Chelostoma rapunculi Bees

“…Follow-up studies and monitoring events are needed to fully understand the interaction between C. rapunculi bees and Malva and Geranium flowers. As more than 70% of plant species, including several of C. rapunculi's host species, have declined in Germany during the last decades (Eichenberg et al, 2020), a broadening of the host range might reduce the high dependence of C. rapunculi on Campanula plants.…”