Conservation-oriented, sustainable grassland management in Saxony-Anhalt for the promotion of habitat types 6210(*), 6440, 6510 and the responsibility species Dactylorhiza majalis (NaturGrüST)

The results of the project contribute to a sound scientific basis for the management of habitat types (LRT) 6210(*) (calcareous dry grasslands), 6440 (fireweed floodplain meadows), and 6510 (lowland hay meadows), as well as wet and marshy meadows. The findings and recommendations can be used to derive measures for regulations, management plans, or maintenance and development plans. They can also be used in the further development of funding guidelines. Furthermore, the practical measures of the project have a direct positive impact on the species Dactylorhiza majalis (broad-leaved marsh orchid).

Project priorities

• Investigation of the influence of management factors on the conservation status of grassland communities on two sample areas of LRT 6510 (submontane fresh meadow in the southern Harz Mountains) and 6440 (floodplain grassland of the Elbe floodplain near Dessau)
• Revitalization of wet and marshy meadows with current or historical occurrences of the species Dactylorhiza majalis (broad-leaved marsh orchid)
• Influence of management factors on population development and reintroduction of Dactylorhiza majalis (broad-leaved marsh orchid)
• Updating and expanding (LRT 6210) the grassland guide, public relations work, and knowledge transfer

Project region

Areas in Hayn, Dessau, Südharz and Burgenlandkreis

Further project details

• Hayn management trial (submontane fresh grassland - LRT 6510)

  Area characteristics

  Elevation: approx. 440 m above sea level	pH value: 5.28 (± 0.18)
  Annual precipitation: 600 mm	Phosphorus: 4.63 (± 1.08) (mg/100 g soil)
  Annual temperature: 6.5 °C	Potassium: 15.72 (± 3.94) (mg/100 g soil)

   

  In 2017, LRT 6510 (low-nutrient lowland hay meadow) was sown in submontane and mesotrophic forms on shallow soil at the Hayn experimental station of the Landesanstalt für Landwirtschaft und Gartenbau. The seed mixture consisted of 12 grasses, 27 herbs, and 5 legumes. The seed density of the target species was 1.9 g/m². In addition, a mixture of buckwheat (Fagopyrum esculentum), gold-of-pleasure (Camelina microcarpa), and cress (Lepidium sativum) was sown as companion seeds at a seed density of 2 g/m². This allowed the soil to be covered quickly and created improved germination conditions for the target species. The seeds came exclusively from regional propagation.

  After preparing a fine seedbed by plowing, harrowing, and leveling, the seed mixture mixed with corn meal was scattered on the surface (not worked into the soil!) and rolled. Sowing took place very late at the end of June and was therefore not at the optimal time. However, several weeks of rainfall and the protective function of the cover crop led to successful emergence. As part of development maintenance, the crop was cut back to a height of approx. 15-20 cm eight weeks after sowing and mowed after 12 weeks (cutting height approx. 10 cm). In the following year, the trial area presented itself with a closed vegetation cover and abundant flowering.

  

  

  

  

  

  

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  Since 2018, the management trial has been investigating practice-relevant combinations of mowing and fertilization in a fully randomized trial design on a productive grassland site with utilization interest (taking into account the grassland premium, nature conservation support through agri-environmental programs, and standard practice). The following usage variants are being tested with different fertilizer application rates (N, P, K):

  • Single-cut mowing
  • Two-cut mowing
  • Three-cut mowing
  • Mulching in summer (July)
  • Mulching in autumn (October)
  • Mulching twice

  

  

  

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  Composition of the seed mixture for establishing a fresh meadow (submontane form of LRT 6510) in Hayn

  

  

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• Management trial in Dessau (burning umbel meadows - LRT 6440)

  Area characteristics

  Elevation: approx. 59 m above sea level	pH value: 4.85 (± 0.15)
  Annual precipitation: 584 mm	Phosphorus: 0.93 (± 0.33) (mg/100 g soil)
  Annual temperature: 9 °C	Potassium: 11.27 (± 2.05) (mg/100 g soil)

   

  The Fischerhüttenwiesen near Dessau are located east of Waldersee and north of the federal highway to Vockerode. They are largely surrounded by Lake Löbben, an oxbow lake. They are located in the „Mittelelbe“ Biosphere Reserve and the „Dessau-Wörlitzer Elbauen“ FFH area. This is a large area of seasonally wet grassland (approx. 67 ha) with a constant occurrence of characteristic seasonally wet meadow species (e.g. Selinum dubium, Galium boreale, Sanguisorba officinalis). At least in the northern part, it can be classified as habitat type 6440. It has a high species diversity and a high proportion of species characteristic of this habitat type. In terms of plant sociology, the area can be classified as Sanguisorbo officinalis-Silaetum silai Klapp 1951 (silene-meadow grass meadow). The area is located in the recent floodplain, but is rarely flooded.

  Since 2010, the management trial has been analyzing and evaluating the effects of various grassland management factors on species composition, vegetation structure, conservation status, yield, feed value, and soil chemical properties.

  The following usage variants are being tested with different fertilizer variants (N, P, K):

  • Two-cut mowing with a short break between uses
  • Two-cut mowing with long break between uses
  • Three-cut mowing at silage maturity
  • Three-cut mowing with first cut to pasture maturity

  

• Dactylorhiza majalis (broad-leaved marsh orchid) in the Karstlandschaft Südharz Biosphere Reserve

  Situation in the South Harz Biosphere Reserve

  The Arbeitskreis heimische Orchideen Sachsen-Anhalt e. V. (AHO) provided data on 109 locations with current or historical occurrences of the species Dacytlorhiza majalis in the Biosphere Reserve Karstlandschaft Südharz. Of these, 81 areas were visited in spring and early summer 2017.

  

  Dactylorhiza majalis was confirmed in 43 of the 81 meadows mapped (53%). Almost a third of the areas now only have very small populations with a maximum of 50 individuals. Only four meadows have orchid populations with more than 500 individuals.

  

  Vegetation structures and associated plant species

  The meadows with recent occurrences can be divided into six different types in terms of their species composition and vegetation structure:

  Wet and marshy meadows
  (1) with higher coverage of Carex panicea (> 10%)
  (2) with higher coverage of Carex nigra (> 20%)
  (3) with high coverage of Scirpus sylvaticus (> 30%)
  (4) with classic wet meadow species (indifferent mixed group)
  (5) dominated by Filipendula ulmaria
  (6) dominated by Petasites hybridus

  

  

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  Plant species associated with Dactylorhiza majalis within vegetation structure types (consistency class III = 40-60%, IV = 61-80%) (n = 49)

   

  

  Condition and use of the meadows

  At 58%, the majority of the areas were in moderate to poor condition. These areas were characterized by an increased occurrence of tall forb species or the dominance of large sedges or wood rushes and denser and higher litter layers. Woody plants played a rather minor role. Only in a few areas was the occurrence of black alder or raspberry observed.

  As expected, the mowed areas were generally in very good condition, while abandoned areas were only in moderate to poor condition.

  

• Dactylorhiza majalis – “Struthwiese” management trial

  Area charakteristik

  Elevation: approx. 422 m above sea level	pH value: 4.67 (± 0.12)
  Annual precipitation: 500-700 mm¹	Phosphorus: 1.27 (± 0.21) (mg/100 g soil)
  Annual temperature: 7-7.8 ˚C¹	Potassium: 7.86 (± 1.16) (mg/100 g soil)

   

  Since 2017, the effects of five different management variants on the orchid species Dactylorhiza majalis (broad-leaved marsh orchid) have been tested in the eastern part of the South Harz Karst Landscape Biosphere Reserve near Wettelrode. The fully randomized plot trial includes the following management variants of different types, intensities, and timing:

  • One-year waiver of use
  • mulching
  • Single cut – early mowing (before flowering)
  • Single cut – summer mowing (at seed maturity)
  • Two cuts – early mowing/late mowing

  ¹ Angaben für Südliches Harzvorland (LE 4.6) in Reichhoff, L.; Patzak, U.; Lamottke, M.; Reichhoff, K. & G. Warthemann (2001): Die Landschaftsgliederung Sachsen-Anhalts. Ein Beitrag zur Fortschreibung des Landschaftsprogrammes des Landes Sachsen-Anhalt. – Auftraggeber: Ministerium für Raumordnung, Landwirtschaft und Umwelt des Landes Sachsen-Anhalt & Landesamt für Umweltschutz Sachsen-Anhalt. – Magdeburg/ Halle: 331 S.

  

  

  In addition to the impact of cultivation on existing populations, spontaneous recolonization of open ground patches is also being investigated. To this end, at the time of seed ripening of Dactylorhiza majalis, the topsoil and vegetation were completely removed (plagged) from 1 m² of the plots in the cultivation variants. It remains to be seen whether the orchid will establish itself in the area of open ground that has been created. The formation of protocorms has already been confirmed.

  

  

  

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  Since 2017, success has been monitored annually in May/June by recording vegetation data. In addition, Dactylorhiza majalis individuals are counted and population biology characteristics are recorded (growth height, number of leaves, maximum leaf length, length of inflorescence, number of individual flowers, number of seed heads).

   

  In cooperation with the Jugendwaldheim (JWH) Wildenstall, a meadow ditch was restored in April 2018.

  

  

• Dactylorhiza majalis – Active reintroduction trial at “Rote Wiese”

  Area charakteristik

  Elevation: approx. 379 m above sea level	pH value: 4.69 (± 0.46)
  Annual precipitation: 500-700 mm¹	Phosphorus: 0.72 (± 0.7) (mg/100 g soil)
  Annual temperature: 7-7.9 ˚C¹	Potassium: 10.18 (± 4.48) (mg/100 g soil)

   

  In 2017, an experiment was set up on a second test site in the eastern part of the biosphere reserve (Rote Wiese) to actively reintroduce Dactylorhiza majalis. The aim here is to investigate the conditions under which D. majalis can be successfully established through sowing. The test area is subject to the land management practices used to date (mowing once a year in July with removal of the mowed material). As there is already a population on the site, it can generally be assumed that the location is suitable for the species.

  The reintroduction trial comprises six different variants, including two different intensities of open ground creation:

  • Sod cutting flat
  • Sod cutting deep
  • Sod cutting flat + seeding
  • Sod cutting deep + seeding
  • Without sod cutting+ seeding
  • Control

  In addition, the study examines whether the Dactylorhiza seeds sown on the plots, which have been disturbed to varying degrees, actually germinate. The investigations are based on the method described by Rasmussen & Whigham (1993). For this purpose, approximately 700 seeds were placed in a small bag made of plankton net. This was stretched across a slide frame. Ten slide frames were used per variant and repetition. After each draw, two slide frames were removed and examined under a microscope.

  ¹ Angaben für Südliches Harzvorland (LE 4.6) in Reichhoff, L.; Patzak, U.; Lamottke, M.; Reichhoff, K. & G. Warthemann (2001): Die Landschaftsgliederung Sachsen-Anhalts. Ein Beitrag zur Fortschreibung des Landschaftsprogrammes des Landes Sachsen-Anhalt. – Auftraggeber: Ministerium für Raumordnung, Landwirtschaft und Umwelt des Landes Sachsen-Anhalt & Landesamt für Umweltschutz Sachsen-Anhalt. – Magdeburg/ Halle: 331 S.

  ² Rasmussen, H.N. & D.F. Whigham (1993): Seed ecology of dust seeds in situ: A new study technique and its application in terrestrial orchids. American Journal of Botany 80 (12): 1374-1378.

  

  

  

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  On the variants without topsoil disturbance (without sod cutting), the first protocorms could be counted just a few weeks after application. Protocorms were only detected in the stripped variants during the following growing season.

  Since 2018, success has been monitored annually in May/June by means of vegetation surveys. In addition, Dactylorhiza majalis individuals are counted and population biology characteristics are recorded (growth height, number of leaves, maximum leaf length, length of inflorescence, number of individual flowers, number of seed heads).

• Dactylorhiza majalis – Reintroduction and population enhancement

  Measures for the reintroduction and population enhancement of Dactylorhiza majalis in the Karstlandschaft SüdharzBiosphere Reserve

  In fall 2018, five 1 x 1 m sowing plots were created on ten meadows with extinct or low-density populations. To create low-competition conditions, the topsoil was simply turned over and then 10,000 seeds were sown in each plot. In preparation for sowing, parts of the meadows were restored (e.g., deep motor-manual mowing followed by clearing, restoration of a meadow ditch). Accompanying germination studies are also being conducted here. The sowing plots were then protected from wild boars by placing wire mesh over them.

  

  

  

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• Dactylorhiza majalis – Germ test

  As part of species conservation issues relating to the Dactylorhiza majalis species in the “South Harz Karst Landscape” biosphere reserve in Saxony-Anhalt, studies were conducted on the germination rate as a vitality parameter for the species. For this purpose, seed samples from various locations were surface-sterilized under laboratory conditions and placed without mycorrhiza (asymbiotic) on a nutrient medium that had been tested in a preliminary experiment. After 42 days, the germinated and non-germinated seeds were counted under a binocular microscope and the germination rate was determined.

  

  

  

  

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• Dactylorhiza majalis – vitality studies

  In 2018, the following vitality parameters were analyzed in 20 randomly selected Dactylorhiza majalis individuals from 20 populations of varying sizes in the biosphere reserve: plant height, inflorescence length, number of flowers and leaves, maximum leaf area, and number of filled seed capsules. These were then examined for correlations with population size. Possible influencing factors were also included in the evaluation.

  Due to the small sample size, the populations were divided into two classes for the evaluation: populations with ≤ 100 individuals and > 100 individuals. Populations with > 100 individuals were found to have significantly longer inflorescences than populations with ≤ 100 individuals. In contrast, small populations had a slightly significantly higher number of filled seed capsules and also a slightly significantly higher ratio of flowers to filled seed capsules. No direct correlation between population size and plant vitality could be demonstrated.

  Furthermore, it was examined whether the two population size classes differed in terms of biotic structure parameters. Small populations with ≤ 100 individuals had less favorable growth conditions. Significantly higher vegetation and higher litter thickness and cover were detected.

  

  

  

  

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  ¹ Klingmann, L. (2019): Vitalität von Dactylorhiza majalis (RCHB.) P.F. HUNT ET SUMMERH. in unterschiedlich großen Populationen des Südharzes. Masterarbeit. Hochschule Anhalt, Bernburg. 60 S. –Unveröffentlicht.