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41.
Annelieke Hijkoop Chiara C.M.M. Lap Moska Aliasi Eduard J.H. Mulder William L.M. Kramer Hens A.A. Brouwers Robertine van Baren Eva Pajkrt Anton H. van Kaam Caterina M. Bilardo Lourens R. Pistorius Gerard H.A. Visser René M.H. Wijnen Dick Tibboel Gwendolyn T.R. Manten Titia E. Cohen-Overbeek 《黑龙江环境通报》2019,39(13):1204-1212
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Martin?HeilEmail author Birgit?Baumann Ralf?Krüger K. Eduard?Linsenmair 《Chemoecology》2004,14(1):45-52
Summary. Myrmecophytic plants use obligate ant mutualists as a constitutive
indirect defence mechanism. These plants often produce cellular food bodies (FBs) to
nourish their resident ants. Lipids, proteins, and even highly specialised compounds
such as glycogen have been reported from FBs, but detailed chemical analyses of FB
composition have so far been presented only for Southeast Asian Macaranga
and Central American Piper myrmecophytes. Here we
report the chemical composition of FBs of five myrmecophytic Acacia
(Fabaceae) species from Mexico using HPLC (carbohydrates and proteins) and GC-MS
(lipids). Feeding experiments revealed no hints on any use of external food sources
by the inhabiting Pseudomyrmex ants. These ants
obviously rely completely on FBs and extrafloral nectar provided by their hosts.
The total content of nutrients in Acacia FBs was 15-25% of FB
dry mass, being much lower than in Macaranga or
Piper FBs. Proteins were dominating (8-14 % dm)
in Acacia FBs and thus were present in higher amounts than in
Macaranga FBs, yet in lower amounts than in
Piper. Lipids contributed 1-9 %
of dry mass, showing a lower proportion than in FBs of Macaranga
or Piper. Carbohydrates made up 3-11 % dm, reaching
in most Acacia species the same range as observed in
Macaranga and in Piper FBs.
Water content was 18-24 % of FB fresh mass, and structural tissue obviously made up
a much higher proportion in Acacia FBs than in
Macaranga or Piper
FBs. Both characters might represent an adaptation to producing FBs unprotected at
the leaf tips under dry conditions. Acacia FBs
contain all amino acids and all fatty acids that are considered essential for
insects, and their contents of lipids and proteins are higher than in the leaves
from which they are ontogenetically derived. This indicates a putatively adaptive
enrichment of nutritionally valuable compounds in structures functioning as ant-food. 相似文献
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Eduard Ariza 《Journal of Coastal Conservation》2011,15(4):445-455
In the present paper, the current beach management framework in the North-Western Mediterranean coast (Catalonia, Spain) was
revised. Beach management was analyzed using the concepts of Integrated Coastal Zone Management (ICZM). The history of beach
management in the second half of the 20 century and the new developments in the academic field and in the practical beach
management sector during the last decade were studied. The revision of legal texts and strategies in the Catalan coast allowed
synthesizing all scattered information affecting beach management. A SWOT analysis was performed. The main strengths of the
beach management framework in Catalonia are the public ownership of beaches, which allows the government to carry out a comprehensive
management and the recent data and analysis provided by the adopted National and Autonomous ICZM strategies. The weaknesses
found were related to the functioning of traditional existing institutions. New opportunities are related to the possibility
of establishing new institutions that conduct a more inclusive and proactive management. The main threat is that although
the possibility for a fundamental change in beach management organization exists, resources available are not fully exploited. 相似文献
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