Hydro-ecological relations in the Delta Waters
Hydro-ecological relations in the Delta Waters Hydro-ecological relations in the Delta Waters
The monthly bird-counts in the whole Delta area between 1976 and 1986 have been summarized in PleLninger, et al, 1984. 1985; Meininger asd Van Haperen, 1988, and Baptist and ~ ~ g e1989. r , The average number per species per month pez basin was calculated asd used in further wal~sis. The total number is the sum of these average rnofitbly cows of each spedes in the period 1976-1984. It is the best measure of bird use of w area siace it ie not biased by seasonal patterns. In rrlnter up to 700 000 waterbirde cm be present in the Belta area. Much maller numbers Cccur in summet @ig. 2). Approaimately 80 species MONTH Figure 2 Pattern ~f occurrence of waterbirde in Khe Delta area. The average monthly totals of the period 1976-1984 are given. (Black, waders; hatched, ducks; wbtte, ether wacerbirda)
of waterbirds occur regulsrly. The wst important groups are ducks, waders, geese, gulls and tern; less abundant are grebes, cormorants etc. For all these bim3 species, occurring regdarly, the Delta area has a very important funetion in several stages of their life cycles. Figure 3 Map W£ the World, showing the major migration routes of birds occurring in the Delta area. (Horizontal hatching: major fptertidal areas; vertical hatchins: breeding a d wintering range qf birds using the Delta area) Figure 3 suomlari~qs Chs migins and destinations of birds occurrim in the Delta. In summer important numbers of breeding bads a£ several speeies are present (Meiniqger, 1986). After the breeding season most of these birds migrAte south, some to tPle we6.t coasts of Afrioa, lJfrile other speties are more or less resident. Birds breeding in the .boreal. Subatetic and arctic zone of Europe, Asia. Greenland and North America use the Delta either as B refuelling site on migration between the breeding areas and the wintering grounds [in spring and autumn), or as a wintering site. Many species also moult in che heea. All bhese species have in common a large energy denand a d are hence dependent on an abundant food supply md low levels of disturbance. Their wcurrence show that the Delta area acts as a turntable in large scale movements
- Page 74 and 75: macrophytes livkg on or rooting in
- Page 76 and 77: less predictable for water managers
- Page 78 and 79: ILWNEWIJK, A.. KEIP, C., 1988. De v
- Page 80 and 81: XBE CHANGING TmAL LAMXiCAPE I N TEE
- Page 82 and 83: The storm surke of L&Z1 A.D., knorm
- Page 84 and 85: osi* rn@8IOIP m .SL 4 Has F~~ULB 3
- Page 86 and 87: During the 19th century man starts
- Page 88 and 89: mudflats have retreated some 100-20
- Page 90 and 91: aq811~33a.e~ pue 3pTatlJS uxaJsafi
- Page 92 and 93: Erosion by waves of sandy shoals (c
- Page 94 and 95: Lt has been estimated that the sedi
- Page 96 and 97: Implementafion of the Delta Project
- Page 98 and 99: ECOLOGICAL DEVELOWdENT OF SALT MAKS
- Page 100 and 101: fn tidal water systems sedimentatio
- Page 102 and 103: hierarchical position. Tn the egtua
- Page 104 and 105: Of course. tke environmental change
- Page 106 and 107: wind erasson, desaliuation, aeratio
- Page 108 and 109: Fonner tirtal flats with saltmarsh
- Page 110 and 111: Grevelingen. Lake Veere and Krammer
- Page 112 and 113: As mentioned above aa important que
- Page 114 and 115: A seaond important perspective for
- Page 116: BEEEXNX, W.D. and 80ZBf&. J. L9M. T
- Page 119 and 120: are determining the dfstrlbution af
- Page 121 and 122: this volume or in Duutsaa, et aL, 1
- Page 123: artificial waterflow was created af
- Page 127 and 128: . DISTRIBUXIOBI OF WATEJBIRoS OVER
- Page 129 and 130: small bird$ extludiag them vill net
- Page 131 and 132: In order to lsok for relatiouehips
- Page 133 and 134: Table 3 Biomass of macroroobenthos
- Page 135 and 136: freshwater basins. Clearly the pres
- Page 137 and 138: scmthem bottueary o-f the winter di
- Page 139 and 140: OCLURRENCE AND DIET QF B ~T .tUQ 80
- Page 141 and 142: 5.2 H- factors Next to all fartors
- Page 143 and 144: Bewick's Swans (Cygnus columbariusl
- Page 145 and 146: m's activiries do not always have t
- Page 147 and 148: measure affecting food supply or av
- Page 149 and 150: DOQiWT$QS, G. 4 TWISK, F., 1987. De
- Page 151 and 152: MEININGEB, P.L. and HAPEREX, A.M.M.
- Page 153 and 154: PISCIVORES Litfle Grebe Great Crest
- Page 156 and 157: IPYBRO-EGOLOOIOAL BELATIONB ZN THE
- Page 158 and 159: apart from upstream purification; -
- Page 160 and 161: Storm surge barrier Eastern Scheldt
- Page 162 and 163: - In addition to existing managemen
- Page 164 and 165: Nature is pliable. Belattvely young
- Page 166 and 167: Ro. 1. No. 2. SQ. 3. Investigations
- Page 168 and 169: 25. The relation between water quan
The monthly bird-counts <strong>in</strong> <strong>the</strong> whole <strong>Delta</strong> area between 1976 and 1986<br />
have been summarized <strong>in</strong> PleLn<strong>in</strong>ger, et al, 1984. 1985; Me<strong>in</strong><strong>in</strong>ger asd Van<br />
Haperen, 1988, and Baptist and ~ ~ g e1989. r , The average number per<br />
species per month pez bas<strong>in</strong> was calculated asd used <strong>in</strong> fur<strong>the</strong>r<br />
wal~sis. The total number is <strong>the</strong> sum of <strong>the</strong>se average rnofitbly cows<br />
of each spedes <strong>in</strong> <strong>the</strong> period 1976-1984. It is <strong>the</strong> best measure of bird<br />
use of w area siace it ie not biased by seasonal patterns.<br />
In rrlnter up to 700 000 waterbirde cm be present <strong>in</strong> <strong>the</strong> Belta area.<br />
Much maller numbers Cccur <strong>in</strong> summet @ig. 2). Approaimately 80 species<br />
MONTH<br />
Figure 2 Pattern ~f occurrence of waterbirde <strong>in</strong> Khe <strong>Delta</strong> area. The<br />
average monthly totals of <strong>the</strong> period 1976-1984 are given.<br />
(Black, waders; hatched, ducks; wbtte, e<strong>the</strong>r wacerbirda)
Change language