SUCCESSION

	ECOLOGICAL SUCCESSION - THE 
	CHANGE IN SPECIES COMPOSITION AND 
	COMMUNITY STRUCTURE AND FUNCTION 
	OVER TIME

		CONSISTS OF A SERIES OF SERAL 
		STAGES THAT COMPRISE THE SERE 

			THE FINAL SERAL STAGE, WHICH 
			IS SELF-MAINTAINING IS THE 
			CLIMAX COMMUNITY

				CLIMAX THEORIES

					MONOCLIMAX 
					(CLIMATIC CLIMAX) - A 
					REGION HAS A SINGLE 
					CLIMATICALLY 
					DETERMINED CLIMAX 
					COMMUNITY

					POLYCLIMAX THEORY - 
					A REGIONS MAY HAVE 
					SEVERAL CLIMAX 
					COMMUNITIES 
					DETERMINED BY LOCAL 
					ENVIRONMENTAL 
					CONDITIONS

		TWO CATEGORIES OF SUCCESSION

			PRIMARY - BEGINS IN AN AREA 
			WITHOUT ANY ORGANISMS OR 
			PRODUCTS OF ORGANISMS

			SECONDARY - BEGINS IN AN 
			AREA THAT HAS SOME 
			ORGANISMS AND/OR PRODUCTS 
			OF ORGANISMS

				IN EITHER CASE

					PIONEER SPECIES - THE 
					FIRST TO BECOME 
					ESTABLISHED

						OFTEN r-SELECTED 
						GENERALISTS

		SUCCESSION MAY RESULT FROM 
		EITHER:

			A SERIES OF ENVIRONMENTAL 
			CHANGES INDUCED BY THE 
			ORGANISMS OF EACH SERAL 
			STAGE (AUTOGENIC)

			OR, CHANGES IN 
			ENVIRONMENTAL CONDITIONS 
			DUE TO SOME EXTERNAL CAUSE 
			(ALLOGENIC)

	MODELS OF SUCCESSION

		FACILITATION MODEL - 
		SUCCESSION IS DRIVEN BY
		AUTOGENIC PROCESSES

		INHIBITION MODEL - SUCCESSION 
		IS DRIVEN BY COMPETITION, THE 
		EVENTUAL WINNERS MAKE UP THE 
		³CLIMAX² COMMUNITY

		TOLERANCE MODEL - CURRENT 
		SPECIES ARE GRADUALLY REPLACED 
		BY THOSE THAT HAVE TOLERANCES 
		FOR LOWER LEVELS OF RESOURCES 

	

	THE BIG DEBATE ABOUT SUCCESSION 
	CONCERNS THE NATURE OF THE 
	COMMUNITY

		ORGANISMAL CONCEPT (HOLISTIC 
		PROCESSES)

		INDIVIDUALISTIC CONCEPT 
		(REDUCTIONISTIC PROCESSES)