Critical Influences.

Ambient temperature

A certain water temperature is usually necessary for an algal bloom to occur, although some species bloom in different locations in the world over a broad range of temperatures. A number of inter-related issues affect the amount of energy available for growth of submersed aquatic vegetation and algae. Although water issuing from the springs tends to a certain temperature year round, distance from the spring head, cloudiness, the angle of the sun in the sky and prevailing wind direction according to weather conditions, allow air temperature to influence water temperature and consequently water clarity.

Water clarity can be seen to change for the better over night, say, as a cold front reduces ambient temperature as it moves through, especially had the sun moved southwards late in the year. With less energy available, suspended matter in the water column, reducing visibility, ceases to grow and falls to the bottom to increase water clarity.

A further effect of water temperature is its use as a winter thermal refuge for the manatee which is a function of the amount of fresh water discharge from the springs. A reduction of this fresh water input by the effect of drought, over pumping or withdrawals for bottling, will reduce the amount of warmer water available as thermal refuge.

Stream velocity

Stream velocity is often overlooked as a prime contributor to the degree to which algal blooms form. In faster moving streams algal elements which are attached to the bottom (benthic) or to plants are exposed to nutrients of the water column for less time and grow less quickly. Algal elements suspended in the faster moving streams tend to disperse as opposed to linking with benthic or attached alga elements. In slower moving streams or in stagnant waters algae tend to grow more aggressively.

Persistent bioaccumulative substances

The need to control bioaccumlative substances in sediments is becoming increasingly important. Over time, whether administered in excess as pesticides or weedkillers on land, or to kill submersed aquatic vegetation or algae in our water bodies, chemical poisons accumulate in sediment even though they may become undetectable in water. In combination with each other, and others from, for example, power plant effluent, vehicle emissions and golf courses, they can make a toxic "soup", poisonous to o-microrganisms, the marine food web, consuming biota and eventually also humans. Methyl mercury from power plant effluent, arsenic from golf course run off, products of combustion from motor vehicles and agriculture chemical additives are among the harmful additives as persistent bioaccumlative substances.

Chemical controls

Among the chemical compounds applied to Citrus County water bodies to control submersed plants or algae, are Peroxide, Diquat dibromide, Dipotassium of endothall and Glyphosate that are found in Reward, Aquathol K, Aquathol Super K, and Aqua-star respectively, which are acknowledged to combine to become bioaccumulative substances.

Moreover, there is a tendency for target species to develop resistance to the chemicals requiring increased dosage or frequency of application, adding to costs and making bioaccumulation affects worse.

In the period In 1978/9 six tons of elemental copper were applied to deal with invasive SAV in Kings Bay and Crystal River. Anecdotally, dramatic increases in sediment muck followed, with reduced fish stocks, decreased water clarity, and algae blooms noticeably increased. Manatees were found to have traces of copper in tissues. Some areas of the bay have remained devoid of SAV almost thirty years later, rumor has it that copper in the sediment is the culprit. Consequently, there is citizen reaction against applying chemicals again.

Sovereignty land issues

Springs and spring runs affected tidally suffer erosion from the twice a day scouring of tides which accentuate affects of sedimentation, pollutant run off and erosion, and special protective measures have been enacted into law in F.A.C. 18-21.004. Ms. Connie Bersok, Head of the Florida Springs Initiative at FDEP, Tallahassee, on 18 October, 2007, wrote:

"In addition, the comprehensive plan should reference Chapter 18-21.004(6), F.A.C. This rule section addresses minimal protective measures for those springs that are sovereign submerged lands (not private). Normally, these provisions would be implemented by the WMD or DEP during the environmental resource permit (ERP) review. However, there may be projects that do not require an ERP but would still be subject to these state land management criteria."

Springshed buffering

The Florida Department of Environmental Protection, The Department of Community Affairs, and 1000 Friends of Florida, have together published a manual entitled, "Protecting Florida's Springs - Land Use Planning Strategies and Best Management practices". It advocates local government create Overlay Protection Districts, having delineated primary and secondary zones, even in developed springsheds, to contain damage being done to water quality and restrict added damage by neglectful development. Strategies to be employed include, zoning and stewardship practices, land acquisition and conservation easements, and voluntary stewardship programs which should be reflected in local government comprehensive plan policies.

Permeability of recharge areas (Percolation rates)

The easterly slopes of the Brookesville Ridge overlay a poorly contained area of the Floridian and Surficial Aquifers, meaning that rainfall quickly collects excess nutrients and pollutants as it percolates through sandy soils into the groundwater supplying the sovereignty spring sources for the river systems which empty westwards into the Gulf of Mexico. These river systems as sovereignty spring runs contribute millions of dollars annually to the economy of Citrus County. Each has been determined to be set upon a process of eutrophication which will not only further harm the ecology of the rivers themselves, but will degrade the offshore seagrass meadows inexorably in due time.

Relative to the National Geodetic Vertical Datum (NVGD) of 1929, potentiometric contours show altitude at which water would have stood in tightly cased wells. Contour interval is usually ten (10) feet. They are hashed where approximately located, and hachures indicate depressions.

As is discussed below, the increase in salinity in the spring outlets in Kings Bay emphasizes the need to preserve the source of the fresher water entering the river system in the northeast section of the bay area. The watershed map above shows both the recharge areas and the "contours" of potentiometric underground flows, which suggest that the surviving source of fresh water may well be from the north as opposed to the common belief from the east. It is important that geochemical analysis be used to identify the most probable source of the fresh water so that protective decisions may be taken.

It follows that developments in these recharge areas, and interrupting flows from the north, must be actively discouraged. Otherwise destruction of the very ambiance and quality of life that draws people to Citrus County would be compromized.

Specific conductance (an indication of saltiness)

Kings Bay Sampling Stations	Average of Kings Bay Sampling Stations
	Specific Conductance at Kings Bay Springs

Specific conductance measured in micro siemens per centimeter provides, inter alia, a standardized indication of salinity which allows reliable comparisons to be made over time and from place to place. Ocean salinity has a measure of 50,000 units, equivalent to 34 parts per thousand of salt.

Over a three year period the average SC for Kings Bay has increased steadily by two and a half times. From February to June the SC for the main vent at Tarpon Spring increased by more than four times. From February to June 2007 the SC for Black Spring increased eight times to over 12,000 units, which was four times higher than readings in the bordering SW part of Kings Bay, indicating that the spring discharge was heavily influenced by up-welling of salt water normally laying under the fresh water from which the vent is served with aquifer water - a serious condition arising from drought and over pumping inland. It is interesting to note from the following graphic how saltiness of a spring in Kings Bay changed with the state of tide. In all probability the increases were due to subterranean pressures rather than surface water movements. The rises lagged the tidal highs.

(See also section on Saltiness of Crystal River/Kings Bay under the Current Issues page).