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A  G R I C U L T U R A L I  N P U T R  AT E S

D4

What Is It?

BENCHMARK

Agricultural input rates are estimates of the quantities

Develop

Develop an inventory of actual

of fertilizers and pesticides applied to crops (per unit

agricultural input rates by watershed

time) in order to maintain their economic productivity.

and crop.

and

TA R G E T

These inputs will vary greatly depending on the crop

being cultivated, the intensity and productivity of the

agricultural system, and the management practices of

Reduce

Reduce agricultural input rates by at

each farm.

least

least 30% over the next 15 years.

RED FL AG

Why Do We Measure It?

Any

Any annual increase in agricultural input

The delivery of agrochemicals  -- in the form of

rates.

rates.

insecticides, fungicides, herbicides and fertilizers

-- to marine waters represents one of the most

significant and persistent direct threats to the marine

environment.  Establishing  mitigation  strategies

watersheds of the MAR region. Land use coverage

requires an understanding of the nature, volume

can be used to pinpoint the agricultural areas at the

and sources of agricultural inputs within a given

watershed scale by extent and crop class. These data

watershed, as well as the impact of runoff on the

can then be summarized into an estimate of total

marine environment.

input per hectare within the watershed, based on the

crop-specific land cover data and maps.

Estimates of agricultural input rates help identify

watershed areas that represent a current or

This type of model could be useful for providing

growing source of agrochemical contamination. This

agricultural input estimates to NOAA's Nonpoint

information can be used to pinpoint critical areas of

Source Pollution and Erosion Comparison Tool (N-

intervention where alternative management practices

SPECT) runoff model9. Flow accumulation, marine

and technologies could be introduced to reduce the

dispersion or other similar models could also be used

use of agrochemicals and mitigate potential threats

to estimate the flow and dispersion of agriculture-

to marine ecosystems.

derived pollutants into coastal and marine areas.

The amount of agrochemicals applied in a given area

Estimates of agricultural inputs can be verified in the

is influenced by crop type, soil type, the intensity of

course of direct work and interventions to develop

the cropping system and general farm management

better management practices in collaboration with

practices. Different types of crops require different

agro-industries.

kinds and quantities of agricultural inputs. Large

areas of agricultural production such as citrus groves,

Usefulness

Usefulness

banana plantations or rice fields may also indicate the

presence of high-intensity agricultural systems. Other

Estimates of agricultural inputs are useful when

considerations include substrate type, irrigation and

agriculture-based activities have been identified as

weather impacts.

a critical threat to marine ecosystems and mitigation

strategies to alter inputs (types or levels) are being

How Do We Measure It?

considered. In such cases, the indicator provides

direct information about which watersheds should

Data on fertilizer and pesticide use, if given in terms of

be targeted for agrochemical reductions. Estimating

national totals, are first converted to watershed totals,

agricultural inputismost effectivewhenusingaccurate,

based on estimated percentages of agricultural lands

GIS-based (i.e., spatially explicit) information.

within each watershed. For example, a final result

would be presented as "kg of fungicide per year per

Clearly many factors affect the percentage of

hectare of banana plantation in watershed A."

agrochemicals that actually end up in the marine

environment (e.g., slope, riparian buffers, timing of

It is recommended that a simple, GIS-based model be

use and method of application). Some of these issues

used to estimate agricultural inputs in the different

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