APES - Unit 5: Land and Water Uses Modules 32-34

Sustainability

-Being able to use a resource or engage in an activity without jeopardizing the ability of future generations to engage in similar activities.

-The most important factor in this problem is population size

Sustainability requirements

-Environmental systems must be monitored so they are not damaged beyond their ability to recover.

-Renewable resources must not be depleted faster than they regenerate.

-Nonrenewable resources should be used sparingly.

Sustainable development

-Development that balances current human well-being and economic advancement with resource management for the benefit of future generations should be the goal

Maximum sustainable yield (MSY).

-How much can be taken of a resource in order to continue harvesting it indefinitely

-The best way to do this is to keep a resource population at half of the carrying capacity.†

Problems w/ MSY

-Once a MSY is set, it may take several years/seasons to determine if the set harvest rate was too large.

-Difficulty of calculating birth rates, death rates, and the carrying capacity of the system.

-Externalities are not considered

Externalities

-Costs or benefits affecting third parties not involved

-Reduction of habitat, pollution, or other factors that might affect a population other than harvest amounts

Environmental indicators

-Measurements that describe the current state of an environmental system or the Earth.

Global-scale environmental indicators are:

-Biodiversity

-Food production

-Global surface temperature & CO2 concentration in the atmosphere

-Human population

-Resource depletion

Indicators: Biodiversity

-Worldwide biodiversity (genetic, species, and habitat diversity) has been declining globally, indicating systems are not healthy and humans are not living sustainably.

Indicators: Food production

-Food production has steadily grown since the innovations of the Green Revolution, and has kept pace with population growth.

-There have been some signs of stress, with grain reserves depleting and environmental degradation (Ex: climate change reducing where some crops can grow)

-Future = uncertain. †is†

Indicators: Global surface temperature & CO2 concentration in the atmosphere

-Solar energy is trapped by the thickness of the atmosphere, allowing the planet to become livable.

-Additional greenhouse gasses in the atmosphere trap more of this heat, leading to a warmer planet.

-Additional carbon dioxide from human activities, such as fossil fuel burning, have led to anthropogenic (caused by humans) climate change.

Integrated pest management (IPM)

-Uses a variety of techniques to control pest species while minimizing pesticide inputs into the environment and increasing agricultural output.

-Methods:

-^Crop rotation & intercropping

-^Biocontrols

-^Minimal pesticide controls

Crop rotation

-A planting strategy where different types of crop species are planted from season to season on the same plot of land.

-Prevents pests from getting used to one crop, and prevents crop-specific diseases from settling in.

Intercropping

-A strategy allowing for spacing crops growing at the same time to promote biological interactions. -^In this situation, one crop can attract insect predators for another crop.

Biocontrols

-Allow biological factors to control agricultural pests.

-^Natural predators are predators that occur naturally in the environment, and are ideal for IPM.

Sustainable agriculture

-Fulfills the need for food and fiber while enhancing the quality of the soil, minimizing the use of nonrenewable resources, and allowing economic viability for farmers.

Soil conservation:

-Preventing soil erosion while increasing soil depth, and increasing nutrients and organic matter.

-Methods of sustainable agriculture require more labor and cost, but allow for land to be more productive long-term.

Agroforestry

-Vegetation planted as a windbreak, to prevent wind and soil erosion

-Traditional sustainable farming

Strip cropping

-A form of intercropping that uses different spacing and rooting characteristics to prevent soil erosion

-Traditional sustainable farming

Contour plowing

-Plowing and harvesting parallel to the topographic contours of the land

-Reduces erosion

-Traditional sustainable farming

Terracing

-Farms shape sloping land into flat, step-like terraces

-Traditional sustainable farming

Perennial plants

-Plants that live for multiple years and do not need to be replanted each season

-Modern sustainable farming technique

No-till agriculture

-Annual crop land that is not tilled or plowed in between seasons

-Modern sustainable farming technique

Green manure

-Plant material grown with the intention of plowing it under at the end of the season

-Modern sustainable farming technique

Use of limestone

-Calcium carbonate sedimentary rock that has been ground up or crushed to be used as a fertilizer

-Modern sustainable farming technique

-aka diatomaceous earth

Rotational grazing

-Rotating farm animals to different pastures and fields so overgrazing doesn't occur

-Modern sustainable farming technique

-Negative --> Need a lot of land

Organic agriculture:

-Production of crops to sustain or improve the soil w/o using synthetic pesticides or fertilizers.

-Uses natural/ecological systems

-Inc soil mass, organic matter, and biological activity

-Retains as much organic matter and nutrients in the soil as possible

-Reduces adverse environmental effects of agriculture (ex: loss of nutrients)

The Delaney Clause in the Food, Drug, and Cosmetic Act

-Designed to prevent potentially harmful, cancer-causing food ingredients.

Aquaculture.

-The cultivation of seafood

-Allows for an increase of fish production for food without depleting or collapsing fisheries.

-Demand for fish is increasing with population, but the increase in food provided comes primarily from aquaculture.

Aquaculture can be done by floating nets in:

-Near-coastal marine waters

-Coastal ponds (brackish water)

-Inland ponds (fresh water)

-Totally enclosed land structures

Benefits of aquaculture

-Inc in food production

-No need to take extra from fisheries

-Above ground tanks dont allow for escapes or disease spreading

Criticism of aquaculture

-Excessive need for filtering and pumping food and medication

-Disease may proliferate and spread from wastewater

-Nonnative fish may escape

Reforestation

-Restocking trees after clear-cutting allows for repopulation of the forest, erosion reduction, and starts to remove carbon dioxide from the atmosphere

Sustainable forestry

-The method of managing forests to produce wood while also providing clean water, maximum biodiversity, and maximum carbon sequestration.

Sustainable forestry can be achieved by:

-Logging with animals instead of fossil-fuel powered machinery

-Choosing specific species of trees to maintain species evenness and richness

-Avoiding habitat fragmentation

-Minimizing use of wood and lumber in construction and consumer products

Prescribed burns

-Fires deliberately set under controlled conditions, preventing worse fires in the future.

-Originally, the goal was to suppress fires, but this led to large quantities of dead biomass, making forest fires worse.