Fragm. Flor. Geobot. 45(1–2): 445–456, 2000 Distribution of Triglochin maritimum (Juncaginaceae) in Poland ZOFIA SOTEK SOTEK, Z. 2000. Distribution of Triglochin maritimum (Juncaginaceae) in Poland. Fragmenta Floristica et Geobotanica 45(1–2): 445–456. Kraków. ISSN 0015–931x. ABSTRACT: The distribution map of Triglochin maritimum L. and list of localities in Poland is given, based on herbarium materials, the literature and unpublished data. In Poland T. maritimum occurs on wet and usually saline meadows along the Baltic coast and in inland localities. KEY WORDS: Triglochin maritimum, halophyte, distribution in Poland Z. Sotek, Department of Botany, University of Szczecin, Felczaka 3a, PL–71–412 Szczecin, Po- land; e-mail: [email protected] INTRODUCTION The genus Triglochin L. belongs to the family Juncaginaceae and in the Polish flora is represented by two species, Triglochin palustre L. and Triglochin maritimum L. The more often met T. palustre grows in wet meadows and on the banks of reservoirs. The much rarer T. maritimum is recorded on wet and usually saline meadows. Sometimes these two species are found together. The diagnostic features clearly differentiating the two taxa are the inflorescence (T. palustre – loose with adherent petioles; T. maritimum – dense with detached petioles), the number of stigma (T. palustre – 3; T. maritimum – 6) and the fruit (T. palustre – clavate, not appessed to scape; T. maritimum – oblong-ovoid, appessed to scape). The aim of the study was to determine the Polish distribution of Triglochin mariti- mum, which is classified as vulnerable in Western Pomerania and Greater Poland (Wiel- kopolska) (Z˙ ukowski & Jackowiak 1995). MATERIAL AND METHODS The distribution map and list of localities of Triglochin maritimum in Poland was made on the basis of revised herbarium material (13.1%), the literature (75.1%) and unpublished data (11.7%) taken from the ATPOL database. The total number of floristic data was 169. Names of villages found in German lit- erature which do not exist any longer are given in brackets and accompanied by the name of the nearest existing village or town. Names of Polish villages difficult to find on the map are also given in brackets 446 Fragm. Flor. Geobot. Ann. 45, Pars 1–2, 2000 together with the names of the nearest larger village or town. The distribution map was made using the 10 × 10 km ATPOL grid square system (Zaja˛c 1978). Information about the conditions of occurrence of T. maritimum were taken from the cited literature and from the descriptions on the herbarium labels. Abbreviations for the names of herbaria follow Mirek et al. (1997). GENERAL DISTRIBUTION According to Pawłowska’s classification (1966), Triglochin maritimum belongs to the Holarctic geographic element and Circumboreal subelement. In Europe it occurs along the coasts of the Atlantic Ocean and North Sea, Norwegian Sea and Barents Sea, as well as in scattered inland localities and on the northern coast and islands of the Mediterranean Sea. In Asia it is common in the temperate zone (e.g., the Altai and Tien Shan Mts), locally in the subarctic zone (e.g., Kolsk Peninsula, eastern Siberia), in the Caucasus and in the northern part of the Anatolia Highland. In North America this species occurs from Alaska and Labrador to about 40 N, and in the Rocky Mts reaches northern Mexico (Hul- tén & Fries 1986; Markgraf 1981; Oberdorfer 1983; Rothmaler 1990). It has been also reported on the west coast of South America from central Chile to Fiery Island (Markgraf 1981). The distribution map of T. maritimum given by Hultén and Fries (1986) presents the ranges of two subspecies: T. maritimum subsp. maritimum and T. maritimum subsp. asiaticum Kitag. The range of the former is generally in agreement with that given by Markgraf (1981) for T. maritimum, except for the area in South America. The range of T. maritimum subsp. asiaticum is restricted to Eastern Asia: the Japanese Islands, Korean Peninsula, the lower catchment of the Amur river and Sakhalin. DISTRIBUTION IN POLAND In Poland Triglochin maritimum occurs along the Baltic coast and in inland localities. It is frequently noted from saline soil along the Baltic coast. At present the largest inland populations of this species are found in the Kujawy region, Greater Poland (Wielkopol- ska) and near Łe˛czyca (Central Poland). The easternmost locations have been found on the lower Nida river and in the eastern part of the Nizina Mazowiecka lowland. Before 1945 numerous localities of T. maritimum were found in the Odra river catchment area between Wrocław and Słubice, but have not been confirmed recently. Nor has there been confirmation of the majority of inland localities in Pomerania, the Chełmin´skie and Iław- skie Lake Districts, and Warmia (Fig. 1). Triglochin maritimum is a character species of the class Asteretea tripolium Westh. & Beeft 1962 (Oberdorfer 1983) and of the association Triglochino-Glaucetum mariti- mae Wilk.-Mich. 1963 (Wilkon´-Michalska 1963; Matuszkiewicz 1982; Nienartowicz & Wilkon´-Michalska 1993). Along the coast it is a constant component of communities growing on wet and salty meadows belonging to the association Armerion maritimae Br.-Bl. & De Leeuw 1936. On both marine and inland saline soil this species is often accompanied by Juncus gerardi Lois. and Glaux maritima L. Z. Sotek: Distribution of Triglochin maritimum in Poland 447 Fig. 1. Distribution of Triglochin maritimum L. in Poland. ● – current locality; ❍ – locality from the literature or herbaria not confirmed after 1945. The degree of affinity of Triglochin maritimum to saline soils changes within its range. In Central Europe it is considered an obligatory halophyte, and in Southeastern Europe a facultative halophyte. It is reported mainly from wet salty meadows, pastures and saline marshes. The inland localities occur near salt springs, salt works and sodium works. WHY TRIGLOCHIN MARITIMUM LOCALITIES DISAPPEAR AND NEW ONES EMERGE The disappearance of Triglochin maritimum localities is often a result of drainage of meadows, desalting and fertilization of soils, increasing urbanization, and cultivation of new land (Wilkon´-Michalska 1963; Piotrowska 1974, 1976; Bosiacka 1999). On the other hand, secondary localities favoring growth of halophytes appear as a result of human activity, for example when soil is polluted by chlorine compounds in industrial waste, when salt is used on to melt snow on roads, or when sewage is disposed in rivers. One illustration of this is the increased number of T. maritimum localities near Gdan´sk Bay and Puck Bay relative to the number given at the turn of the 19th/20th centuries. This 448 Fragm. Flor. Geobot. Ann. 45, Pars 1–2, 2000 increase in particularly seen near the Martwa Wisła river, from its mouth to the Wisła Przekop river (Piotrowska 1980). At present it is difficult to predict the further fate of this species in Poland: along with reports of new localities there has been a gradual reduction of the number of known localities due to the instability of its habitats. The scale of the phenomenon can be illus- trated by the fact that 119 of 308 Triglochin maritimum sites have not been confirmed since 1945, but 155 have been reported for the first time. The high number of sites reported for the first time after 1945 certainly reflects increased interest in studying halophytes in some regions of the country. List of localities in Poland Explanations: env. – environs; Germ. – German; n. – near; unpubl. – unpublished; val. – val- ley, Schrs. Naturf. Ges. Danzig – Schriften der Naturforschenden Gesellschaft zu Danzig. GRID SQURAE AB: PROV. ZACHODNIOPOMORSKA. 08 –N from Włodarka (Czubin´ski 1951), Trze- busz-Mrzez˙yno, leg. H. Piotrowska 1968 (UGDA), Mrzez˙yno (Piotrowska 1974); 09 – Dz´wirzyno (Olesin´ski L. 1968 – unpubl. ATPOL); 14 – Mie˛dzywodzie (Piotrowska 1966), Dziwnów – Mie˛dzy- wodzie (Zaja˛c A. & Zaja˛c M. 1993 – unpubl. ATPOL); 15 – Dziwnów (Piotrowska 1966), between Łowno and Zalew Kamien´ski (Zaja˛c A. & Zaja˛c M. 1993 – unpubl. ATPOL); 17 – Niechorze (C´ wiklin´ski E. 1978 – unpubl. ATPOL), n. Lake Liwia Łuz˙a (Holzfuss 1942); 21 – S´ winoujs´cie (Piotrowska 1966); 22 – Mierzeja Przytór (Piotrowska 1966), Łunowo (Piotrowska 1974); 23 – Droz˙kowe Ła˛ki (Jasnowski 1962), leg. H. Piotrowska 1968 (UGDA), Mie˛dzyzdroje (Jasnow- ski 1962), Warnowo (Piotrowska 1966), Lubiewo (Piotrowska 1974); 24 – Sierosław (Jasnowski 1962), Kołczewo (Piotrowska 1966), Dusin (Zaja˛c A. & Zaja˛c M. 1993 – unpubl. ATPOL), Ku- kułowo (Zaja˛c A. & Zaja˛c M. 1993 – unpubl. ATPOL), Koprzywskie Łe˛gi (Zaja˛c A. & Zaja˛c M. 1993 – unpubl. ATPOL); 25 – Chrza˛szczewo Island (C´ wiklin´ski 1988), Grabowo (Zaja˛c A. & Zaja˛c M. 1993 – unpubl. ATPOL), Chrza˛szczewko (Zaja˛c A. & Zaja˛c M. 1993 – unpubl. ATPOL), Kanał S´ winiec N from Kamien´ Pomorski, leg. F. Celin´ski 1961 (POZ); 26 – S´ wierzno (C´ wiklin´ski E. 1978 – unpubl. ATPOL); 31 – Mielin (Jasnowski 1962), Mierzeja Karsiborska (Piotrowska 1966); 32 – Kon´ski Smug (Jasnowski 1962), La˛dko (Jasnowski 1962), Karsiborska Ke˛pa (Jasnowski 1962, Sotek & Rogalski 1998), Przytór, leg. A. Kornas´ 1953 (KRA); 33 – Płoci- no (Jasnowski 1962), Dargoba˛dz´ (Piotrowska 1966); 34 – Wolin, leg. K. Rostan´ski 1958 (KTU), (Piotrowska 1966), Rozwarowo (Zaja˛c A.& Zaja˛c M. 1993 – unpubl. ATPOL), Sibin – 0.5 km N (Zaja˛c A. & Zaja˛c M. 1993 – unpubl. ATPOL), Recław (Zaja˛c A. & Zaja˛c M. 1993 – unpubl. ATPOL), Nowe Rekowo (Zaja˛c A. & Zaja˛c M. 1993 – unpubl. ATPOL); 35 – Bagno Rozwarowo, from Rekowo (Zaja˛c A. & Zaja˛c M. 1992 – unpubl. ATPOL); 42 – Podgrodzie (Zaja˛c et al. 1993), Karczno – Nowe Warpno (Zaja˛c et al. 1993), Nowe Warpno (Zaja˛c A. & Zaja˛c M. 1992 – unpubl. ATPOL); 44 – Zatoka Skoszewska (Jasnowski 1962); 51 – Zatoka Nowowarpien´ska (Jasnowski 1962), Karczno (Zaja˛c A. & Zaja˛c M. 1992 – unpubl. ATPOL); 62 – We˛gornik (C´ wiklin´ski E. 1978 – unpubl.