The chemistry, mineralogy, and rates of transport of sediments in the ...

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22 these "known" watersheds . This could be done best, in our opinion, by establishing experimental research watersheds in a variety of representative areas along the route of development . Some experimental research watersheds should be in areas where intensive and widespread technological disturbance will occur, and some should be in areas that are not likely, to be greatly disturbed (for natural history and experimental control purposes, or controlled experimental manipulation of parts of the watershed) . Where possible, these experimental research watersheds should become calibration sites for development in undisturbed regions . For example, estimates of the increase in sediment supply (per unit area of disturbance) to streams caused by technological development of roads or pipelines could have been obtained by designating the Martin and Rengleng Rivers watersheds as experimental research watersheds before the construction of highways and pipelines . Detailed and synthetic studies, involving the disciplines of wildlife, aquatic ecology, hydrology, geology, meteorology, vegetation, soils, permafrost, geomorphology, and engineering would likely allow a more quantative and predictive approach to development in undisturbed regions . Specifically, and for the purpose of using and testing the information and hypotheses in this paper, we recommend the following : 1) that experimental research watersheds be designated in a variety of suitable and representative areas of the Mackenzie Valley and northern Yukon ; 2) that the network of discharge and suspended sediment monitoring stations be increased and maintained in this region for the duration of construction and at least 5 years after completion of the development of roads and pipelines, and that this expansion of Q and SS stations include representative small watersheds within and outside of areas of development ; 3) that meteorological data gathering stations accompany all discharge and suspended sediment stations ; 4) that research into the importance port of sediments be encouraged, and and, and magnitude of bedload transthat it be monitored seasonally ; 5) that the chemistry of suspended sediments be more fully studied, specifically the annual rates of sediment transport of selected heavy metals, pesticides, dissolved and particulate organic matter, and naturally-occurring hydrocarbons . 9
23 CONCLUSIONS 1 . For selected rivers in the Mackenzie and Porcupine drainages, a positive logarithmic relationship was found between a) the annual mass, and the annual mass per unit watershed area of suspended sediments, particulate carbon, nitrogen, and phosphorus, and b) annual discharge . 2 . The magnitude of annual transport rates particulate carbon, nitrogen, and phosphorus controlled by watershed area, relief, forest according to a multiple linear regression of of suspended sediments, and were found to be largely cover, and precipitation, data from selected watersheds . 3 . The slopes (b) of regression lines relating instantaneous suspended sediment concentrations and instantaneous discharge for selected rivers were positively and significantly related to mean annual erosion rates for these same rivers . We propose that these slope values are indices of the erosive power of the river, or the capacity of the river to carry away added sediment . 4 . The intercepts (a) of regression lines relating instantaneous suspended sediment concentrations and instantaneous discharge for selected rivers were interpreted to be indices of the susceptibility of the terrestrial portion of the watershed to erosion by streams and rivers . These intercept values may also be indices of average watershed sensitivity to terrain disturbance from technological development . This hypothesis requires verification by experiments'or-case history studies . 5 . Undisturbed small rivers and streams (Ad 1) transport annually larger amounts of suspe ded sediment, particulate carbon, nitrogen, and phosphorus, per unit water'S}ied area, than do small (Ad
Page 1 and 2: Department of the Environment Minis
Page 3 and 4: iii TABLE OF-CONTENTS Page List of
Page 5 and 6: V TABLE 8 . Page Mean annual rates
Page 7 and 8: vii LIST OF FIGURES Page Figure 1 .
Page 9 and 10: ix ABSTRACT Brunskill, G . J ., P .
Page 11 and 12: xi RESUMt Brunskill, G . J ., P . C
Page 13 and 14: 1 INTRODUCTION In regions of northe
Page 15 and 16: 3 Stream and river bottom sediments
Page 17 and 18: Annual rates of transport were obta
Page 19 and 20: 7 The total mass of sediments remov
Page 21 and 22: 9 Only two clay minerals were found
Page 23 and 24: 11 increased sediment concentration
Page 25 and 26: 13 changes in albedo, and the gener
Page 27 and 28: 15 Increases in the concentrations
Page 29 and 30: 17 which is positively related to w
Page 31 and 32: 19 and velocity (Fig . 1) . For the
Page 33: 21 It will be necessary to quantify
Page 37 and 38: 25 REFERENCES Abrahams, A . D . and
Page 39 and 40: 27 Corbel, J . 1964 . L erosion ter
Page 41 and 42: 29 Hughes, 0 . L ., J . J . Veillet
Page 43 and 44: 33 McRoberts, E . C . and N . R . M
Page 45 and 46: 33 Tarnocai, C . 1973 . Soils of th
Page 47 and 48: , 35 e TABLE 2a . Slopes ') and int
Page 49 and 50: 37 i TABLE 2c . Slopes (b) and inte
Page 51 and 52: i 39 b TABLE 3 . Average annual mas
Page 53 and 54: 41 v b TABLE 5 . Cation exchange ca
Page 55 and 56: N c . P TABLE 7a . Ranges of concen
Page 57 and 58: I a m r TABLE 8 . Mean annual rates
Page 59 and 60: 01 TABLE 10. Mean annual rates of t
Page 61 and 62: 49 TABLE 12 . Significance of regre
Page 63 and 64: TABLE 14 . Mean concentrations of s
Page 65 and 66: 9 Q TABLE 16 . A comparison of annu
Page 67 and 68: TABLE 17 . cont'd River Year Date S
Page 69 and 70: S TAME 17 . cont'd River Year Date
Page 71 and 72: TABLE 17 . cont'd River Year Date Q
Page 73 and 74: It • TABLE 17 . cont'd River Year
Page 75 and 76: TABLE 17 . cant 'd River Year Date
Page 77 and 78: 2 =0.67 100,000- N E Y a 10,000- Y
Page 79 and 80: c 11 I C- 10 - E n I, 0 10- E e 0.1
Page 81: II (m 3 vnnr - ' v In'6 1 r r, m A

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