Weaver (1963) index: //' = - 2 p, In p,, where P, is the 



proportion of individuals in the t'th sptecies. H' has two 

 comjHjnents: number of s{)ecies (S, hereafter termed spe- 

 cies richness), and equitability (J* = H'/H' max = H'An 

 S) (Lloyd and Ghelardi 1964). Both S and J' were com- 

 puted for each 0.1 m^ samples, as was the number of indi- 

 viduals (AO. 



Q-mode or normal cluster analyses (clustering sta- 

 tions by species) were done by James Archie, State Uni- 

 versity of New York, Stony Brook. Czekanowski's coeffi- 

 cient, Cz = 2w/a+b (Bray and Curtis 1957), was used to 

 measure faunfil similarity between each pair of stations. 

 Here a is the sum of abundances of all species found at 

 station A, b is the sum of species abundances for station 

 B, and w is the sum of the lower of the abundance values 

 for each species common to A and B. Abundances were 

 log transformed (loge x + 1), and then single linkage 

 clustering was performed via unweighted pair-group 

 method using arithmetic averages (Sneath and Sokal 

 1973). 



Subsamples were taken from the grabs for analyses of 

 sediment grain sizes, organics, carbonates, heavy metals, 

 microflora, and meiofauna. The latter three topics were 

 subjects of discrete studies, and their methodologies are 

 described elsewhere (respectively Greig et al. 1977; 

 Dudley et al. 1977; Tietjen 1977). Sedimentology studies 

 used a sediment sample collected from each grab with a 

 3.7 cm inner diameter coring tube and frozen. Analyses 

 were performed by James Parks and Alex Rugh, Lehigh 

 University, Bethlehem, Pa. For grain size anedysis, a por- 

 tion of each core sample was wet-sieved through a 62 ^m 

 screen, with retained materials then sieved through a 

 series of 12 screens with meshes from 4 mm to 62 ;^m. 

 Pi{)ette analysis was used to determine the clay and fine- 

 and coarse-silt fractions of the <62 ^lm portion. Orgtmic 

 content was determined by weight loss of dried samples 

 upon treatment with 10% hydrogen peroxide. 



RESULTS AND DISCUSSION 

 Temperature and Salinity 



Temperature and salinity on Cruises 2 and 3 followed 

 expected patterns, as described by Riley (1955), Riley et 

 al. (1952, 1956), Hardy (1970, 1972a, b), and Hardy and 

 Weyl (1970). Temperatures were quite uniform both ver- 

 tically and horizontally in April 1973 (Figs. 2,3), with all 

 values between 4° and 9°C. In late September 1973 tem- 

 peratures ranged from 14° to 22°C (Figs. 4, 5), and gen- 

 erally increased from east to west, with the exception of 

 colder water near the Connecticut River. Again, no pro- 

 nounced vertical stratification was observed. The verti- 

 cal uniformity of temperatures (and moderate bottom 

 dissolved oxygen concentrations, as mentioned below) 

 indicate that mixing of the water column was already 

 well underway by late September. 



Hardy (1972b) noted that a thermocline develops in 

 midsummer, especially in the central basin; thermal 

 layering is also seen in our measurements for July and 



August 1972 (Figs. 6, 7). These Cruise 1 data will not be 

 used in examining horizontal patterns, since the sam- 

 pling period covered 6 wk, and effects of Hurricane Agnes 

 may have obscured the typical distributions. Reflecting 

 the storm's freshwater input, salinity (Figs. 8, 9) was 

 below 22%., for most surface waters in central LIS, and 

 down to 17.8%. at station 28 (Fig. 1), a mile south of the 

 Saugatuck River mouth. 



Salinity on Cruises 2 (Figs. 10, 11) and 3 (Figs. 12, 13) 

 increased gradually from west to east (from 23 to 29.6%. 

 in April and 25.0 to 30.6%. in September). There were 

 only small increases in salinity with depth during this 

 sampling period. 



Nutrients 



Distributions of all nutrients measured in summer 

 1972 exhibit basically a single pattern: very large inputs 

 from the East River at the western end of the Sound 

 dominate nutrient distributions and water quality 

 throughout western LIS. Surface ammonium, for in- 

 stance, approaches 30 microgram-atoms/liter (^gatAiter) 

 at Throgs Neck (Fig. 14). These high levels agree with 

 those reported for August of the previous year by Hardy 

 (1972b). His study showed that to the west ammonium 

 concentrations increased in the East River, to the west of 

 Throgs Neck; a tenfold decrease in surface ammonium is 

 evident from Throgs Neck to just east of Hempstead 

 Harbor (stations 7-10, Fig. 1). Open surface waters of the 

 central basin (as defined by Hwdy 1972b) had moderate 

 ammonium levels (generally 0.5-1.0 ^gat/liter). The Long 

 Island coast east of long. 73°10'W (stations 38-43 in Fig. 

 1) showed similar concentrations. The eastern end of the 

 Sound was characterized by ammonium values of <0.5 

 Mgat/liter, again in agreement with Hardy (1972b). There 

 appear to be ammonium additions in the areas off New 

 Haven-West Haven, Oyster Bay-Northport, and the 

 Nissequogue River (station 37), and p>erhaps off New 

 London and Bridgeport. Ammonium is also presumably 

 being added in the densely populated western end, but 

 this cannot be distinguished from the East River input. 



Bottom ammonium (Fig. 15) was also most elevated in 

 the western end, with values higher than in surface 

 waters except at Throgs Neck. According to the bottom 

 ammonium values, the "plume" of East River water ex- 

 tended east to the Oyster Bay-Stamford transec. 



Surface nitrate (Fig. 16) showed much the same pat- 

 tern as ammonium, with most conspicuous inputs from 

 the East River, Bridgeport, New Haven, and New 

 London. Bottom concentrations (Fig. 17) were greatest 

 from Hempstead Harbor to Throgs Neck, and off New 

 Haven; other tireas with high surface nitrates did not 

 show comparable levels in bottom waters. Nitrite (Figs. 

 18, 19) and orthophosphorus (Figs. 20, 21) distributions 

 also had as their most significant feature elevated values 

 in western LIS. As a rule, noticeably elevated concentra- 

 tions were confined to waters west of long. 73°25' (Lloyd 

 Neck). Values in microgram-atoms per liter for these 

 three nutrients ranged from undetectable to: surface ni- 

 trate, 2.76; bottom nitrate, 2.64; surface nitrite, 3.53; 



