HABITATS

Table 2. Relative significance of impacts of land-based activities on marine habitats based on selected attributes. Spatial scope indicates number of jurisdictions where problem exists (3 states, ME, NH and MA, and 2 provinces NB and NS; 5 indicates all). Temporal scope indicates probable recovery time after stress removed (short-term <1 yr., mid-term 1-5 yr., long-term >5 yr.). Ecological impact indicates nature of stress and likely ecological effect. Socioeconomic impact indicates particular resources or economic considerations possibly at risk. General trend indicates present tendency for activity: increasing, decreasing or stable; historic indicates activity occurred many decades or more ago, but effects persist. A question mark indicates uncertainty and general lack of reliable information.

	HABITATS	SCOPE		IMPACT		GENERAL	OVERALL
ACTIVITY	AT RISK	SPATIAL	TEMPORAL	ECOLOGICAL	SOCIOECONOMIC	TREND	RANKING
sewage	inshore benthic mudflat eelgrass beds	5 5 3 ME NH MA	short	anoxia eutrophication diversity ?	shellfish closures	variable by region	high
dams	salt marsh mudflats	5 4 NB NS ME NH	long ?	sediment dynamics ?	marine productivity? anadromous fish	stable	high
subtidal harvest	inshore benthic eelgrass beds kelp beds	5 3 ME NH MA 5	short ?	habitat loss, structure diversity?	fishery impacts ? marine productivity	increasing	high
tidal restrictions	salt marsh	5	mid ?	habitat loss, invasive plants ? productivity?	marine productivity?	increasing	high
forestry	inshore benthic	3 ME NB NS	long	wood wastes, anoxia smothering?	shellfish?	historical	low
residential development	salt marsh eelgrass beds sand beaches coast. islands	5 3 ME NH MA 3 ME NH MA 5	mid ?	habitat loss disturbance ? erosion, eutrophication	fishery impacts ? marine productivity? seabirds ? wildlife	increasing south stable north	high
intertidal harvest	mud flats rockweed beds	4 NS NB ME NH 2 NS NB	short mid ?	disturbance ? biodiversity ?	shellfish? finfish production?	stable increasing	medium
aquaculture	inshore benthic	3 NS NB ME	short?	anoxia biodiversity	fishery impacts? shellfish?	increasing	medium? high?
dredging	inshore benthic salt marsh eelgrass beds	5 3 ME NH MA 3 ME NH MA	mid?	habitat loss, erosion degradation spoil disposal	marine productivity? fisheries impacts	increasing?	medium
tourism recreation	eelgrass beds sand beach coastal islands	3 ME NH MA 3 ME NH MA 5	mid	disturbance degradation erosion?	marine productivity? seabirds, wildlife disturbance?	increasing rapidly	medium
agriculture	salt marsh	5	mid?	ditching, grazing, salt hay harvest	marine productivity wildlife?	decreasing	medium
diking	salt marsh	2 NS NB	long?	marine detritus loss sediment dynamics	marine productivity? storm surges	historical	high
infilling	salt marsh	5	long?	loss of habitat, burial sediment dynamics?	marine productivity?	decreasing	medium
jetties/groins	sand beach	3 ME NH MA	mid?	erosion, sediment dynamics, currents	tourism impacts habitat loss/gain?	decreasing	medium
coastal armoring	sand beach	3 ME NH MA	mid?	dune dynamics	coastal protection habitat loss?	stable	medium