IB ESS REVIEW

The carrying capacity for each species depends on

- [ ] It's reproductive strategy - [ ] It's longevity - The indigenous resources of the habitat

what is contour farming

Contour farming is farming with row patterns that run nearly level around the hill -- not up and down the hill.

How Contour Stripcropping helps?

Contour stripcropping reduces soil erosion and protects water quality contour stripcropping may help reduce fertilizer costs by providing nutrient inputs naturally

Explain the relationship between soil ecosystem succession and soil fertility.

First, lichens, which grow on rock, appear in a destroyed region. The lichens help break down the rock. Then, as lichens die and decompose, and weathering breaks apart rock, soil begins to form. As soil becomes richer, small plants like mosses and ferns appear, and the lichens start to disappear. The soil continues to become richer as plants continue to die and decompose, and flowering plants and grasses appear, bringing insects to the region. In time, shrubs and small trees cover the region, creating a suitable habitat for reptiles, birds, and mammals. As the shrubs and trees grow, smaller plants die from lack of sunlight and add more organic material to the soil. Eventually, the shrubs and trees die because taller trees cover the region. This all happens gradually over a long period of time.

Why are there flash floods?

Flash floods occur when rainfall and snowmelt cannot infiltrate the soil and runs off on the surface this could be due to the land being hard-baked in hot, dry areas but more due to the impermable surfaces in the cities

UnSustainable wild fishing industry

- [ ] Fish populations can be depleted very quickly - [ ] Once we catch the larger specimens we catch smaller and smaller ones and do not leave them to mature and reproduce - [ ] Commercial farming is informed by the latest satellite technology,gps navigation and Fish finding scanning technology of military quality - [ ] Fishing fleets have become larger and with moderate refrigeration techniques they can stay at sea for weeks or for an Entire season

impacts of fish farms

- [ ] Loss of Habitats - [ ] Pollution - [ ] Spread of diseases - [ ] Escape species including genetically modified organisms which may survive to interbreed with wild fish - [ ] Escape species may also Out compete native species and cause the other population to crash

humans use for fresh water?

-domestic purposes: water used at home for drinking, washing, cleaning -agriculture: irrigation, for animals to drink -industry-including manufacturing, mining -hydroelectric power generation -transport (ships on lakes and rivers) -making boundaries between nations (rivers, lakes)

deep water currents?

-they are due to differences in water density salt and temperature -warm water can hold less salt than cold water so is less dense and rises -cold water holds more salt, is denser so it sinks -when warm water rises, cold water has to come up from the depth to replace it. these are dwellings -when the cold war rises, it too has to be replaced by warm water in dwellings

Types of water pollutants?

1. Anthropogenic (created by humans activities) or natural (volcanic eruptions,agal blossoms 2. Point source or non point source 3. Inorganic or organic 4. Direct or indirect

human impact on the water cycle?

1. Withdrawals-for domestic use, irrigation in agriculture and industry 2. Discharges- by adding pollutants to water, eg chemicals from agriculture, fertilizers, sewage 3. Changing the speed at which water can flow and where it flows- A.In cities building roads and channelling rivers underground or in concentarted areas B. Chanalizing: straightening large sections of rivers in concrete channels to facilitate mor rapid flow through sensitive areas C. With dams, barrages and dykes, making resevoirs 4.Diverting rivers or sections of rivers- A. Many are diverted away from important areas to avoid flood damage B. Some are diverted to dams to improve storage

Sources of freshwater pollutants include:

1.agricultural runoff, sewage, industrial discharge and solid domestic waste 2. Rivers,pipelines, the atmosphere and human activities at sea, both operational and accidental discharges

Maximum sustainable yield

A sustainable yield is the increase in natural capital, ie natural income that can be exploited each year without deleting the original stock or its potential for replenishment

Examples of major changes caused by humans

Aral Sea- Intense irrigation has almost stopped river flow into the sea and lowered the sea´s level (it has shrunk in the area by 90% in the last 50 yrs) Ganges basin- deforestation increases flooding as precipitation is not absorbed by vegetation Run-off from urbanizing areas causing local flooding

Food waste is prevalent in both LEDCs and more economically developed countries (MEDCs), but for different reasons.

As countries develop and consumption increases so does the amount of waste per capita, and pollution becomes a greater problem. There are global, national and local strategies in place to reduce levels of waste and minimize impact on the environment. Global waste production The amount and type of waste produced varies between countries. MEDCs have higher levels of consumption, so many produce more waste than LEDCs. Ireland and the USA produce over 700 kg of waste per person per year. In LEDCs the figure is around 150 kg per person per year. This difference is due to different levels of consumption; it is also more common to reuse items in LEDCs. As a country becomes more wealthy, the demand for consumer items increases. This means that items are replaced more frequently - leading to larger quantities of waste. For example, mobile phones and computers that still work may be discarded for a newer version. In LEDCs waste production is lower because: Less is bought because people are typically on lower incomes Less packaging is used on products Disposable items (eg razors, plastic plates and nappies) are used less Lower literacy levels means there is less production of written material

As the human population grows, along with urbanization and degradation of soil resources, the availability of land for food production per capita decreases.

As the world population continues to grow in almost all continents, great pressure is being placed on arable land, water, energy, and biological resources to provide an adequate supply of food while maintaining the integrity of our ecosystem. As the world population grows, the food problem will become increasingly severe. The most venerable will be population in developing countries. The per capita availability of world grains, which make up 80 per cent of the world's food, has been declining for the past 25 years. Certainly with a quarter million people being added to the world population each day, the need for grains and all other food will reach unprecedented levels.

Commercial, industrialized food production systems generally tend to reduce soil fertility more than small-scale subsistence farming methods.

Commercial, industrialized food production systems generally tend to reduce soil fertility more than small-scale subsistence farming methods.

The structure and properties of sand, clay and loam soils differ in many ways, including mineral and nutrient content, drainage, water-holding capacity, air spaces, biota and potential to hold organic matter. Each of these variables is linked to the ability of the soil to promote primary productivity

Consider mineral content, drainage, water-holding capacity, air spaces, biota and potential to hold organic matter, and link these to primary productivity. Soil structure depends on: Soil texture ( the amount of sand and clay ) dead organic matter earthworm activity Soil structure affects aeration, water-holding capacity, drainage, and penetration by roots and seedlings, among other things. Soil structure refers to the arrangement of soil particles into aggregates (or peds) and the distribution of pores in between. It is not a stable property and is greatly influenced by soil management practices. Primary productivity of soils depend on mineral content drainage water-holding capacity air spaces biota potential to hold organic matter

How Contour Farming helps...

Contouring can reduce soil erosion by as much as 50% from up and down hill farming By reducing sediment and runoff, and increasing water infiltration, contouring promotes better water quality

Increased sustainability may be achieved through: altering human activity to reduce meat consumption and increase consumption of organically grown and locally produced terrestrial food products, improving the accuracy of food labels to assist consumers in making informed food choices, monitoring and control of the standards and practices of multinational and national food corporations by governmental and intergovernmental bodies, planting of buffer zones around land suitable for food production to absorb nutrient runoff.

Farming must feed more people more sustainable. Advances in agricultural science and technology have contributed to remarkable increases in food production since the mid-twentieth century. Global agriculture has grown 2.5-3 times over the last 50 years. This has let food production keep pace with human population growth so that, overall, there are enough calories produced per capita. However, progress toward reducing hunger is variable across the world

Evaluate the relative environmental impacts of two given food production systems.

Food production and the supply chain can have wide-ranging positive and negative impacts on the environment. Negative impacts include escalating water and land use, soil erosion and degradation through loss of fertility or desertification, loss of biodiversity, and intensive use of energy (for production, notably for fertiliser manufacture, and for supply, especially in transport and refrigeration) with associated greenhouse gas emissions Factory farming reduces the amount of land needed for meat production, however, these farms are a serious air and water pollutant. The waste of these animals ends up in the nature and poses a constant risk of drinking water contamination and seriously affects the air quality of the nearby areas. One solution for the problem with animal waste lays in its use for production of biofuel which can then be used for production of electricity but this practice is the exception rather than the rule. Mass meat production has shown main contributors to carbon dioxide emissions which in turn are the main cause of the climate change. The meat industry is estimated to be responsible for about 9 percent of total carbon dioxide emissions which are a result of emissions of various gases from the farms as well as from the microbial activities after application of animal waste as fertilizers. Animal husbandry poses a serious threat to the local ecosystems and biodiversity due to the use of the land for grazing and animal feed production. As much as one quarter of the Earth's surface is used for grazing and about one third of arable land is used to produce animal feed. As a result, the wildlife species struggle with lack of habitat, while some are even threatened with extinction.

Maintenance?

Keep strip widths consistent from year to year. In contour farming, establish a narrow, permanent strip of grass along each key contour line to avoid having to lay out new key lines every year.

Planning?

Longer, steeper slopes may require stripcropping rather than just contour farming. Irregular slopes may require more than one key contour line. Row crop strips need to be roughly the same width as hay or small grains; consider how many acres of row crops you need. Remember, hay strips will rotate to row crops over time. Rotating strips from corn to legumes allows corn to use the nitrogen added to the soil by the legumes. Consider whether herbicide carryover will be a problem. Replace end rows with grass or legumes, which will reduce erosion and make it easier to turn equipment. Use grass waterways where runoff is concentrated. Strip width will depend on slope, equipment and management.

Reduced soil fertility may result in soil erosion, toxification, salination and desertification

Many poor farming and forestry operations encourage erosion. Erosion accelerates when sloping land is ploughed and when grass is removed from semi-arid land to begin dry-land farming. It accelerates when cattle, sheep and goats are allowed to overgraze and when hillside forests are felled or cut indiscriminately. While there are isolated instances of deserts being reclaimed by irrigation or of new forests being planted, man, in the majority of instances, degrades the soil when he begins agricultural operations. Poor management practices can also lead to low organic matter. This will result in poor water infiltration, poor water drainage, saturated soil, or compaction. These practices will limit the ability of water to infiltrate the soil causing an increase in the soil salinity and the soil's ability to buffer salt. Desertification is the accumulated result of ill-adapted land use and the effects of a harsh climate. Human activities that represent the most immediate causes are: over-cultivation exhausts the soil, overgrazing removes the vegetation cover that protects it from erosion deforestation destroys the trees that bind the soil to the land and poorly drained irrigation systems turn croplands salty. the lack of education and knowledge the movement of refugees in the case of war, the unfavorable trade conditions of developing countries and other socio-economic and political factors enhance the effects of desertification. Due to the lack of alternative survival strategies, farmers tend to relentlessly exploit natural resources (food crops, water for drinking and washing, firewood) to the point that they are often over-exploited and cannot regenerate naturally. Soil nutrients and organic matter begin to diminish as intensive agriculture removes quantities of nutrients greater than the soil's natural regeneration capacities. As a consequence, the soil is unable to recover, as it does during fallow periods, resulting is an ever-increasing spiral of environmental degradation and poverty, the principal causes of desertification.

U 5.4.6 The yield of food per unit area from lower trophic levels is greater in quantity, lower in cost and may require fewer resources

Most food chains do not have a fourth or fifth trophic level, because energy is not sufficient to sustain fourth or fifth trophic level. As you progress a trophic level only a percentage is passed on to the next organism (approximately 10%- as a result of the energy required to maintain homeostasis), so it would not be efficient to eat an animal that would give you a small biomass. More people on Earth could be supported for a given area of land farmed if individuals eat lower on the food chain. Eating primary producers instead of eating herbivores could support the same number of people as at present, but with less land degradation because we wouldn't need to have so much land in production. These consequences of a change in our diets result from the basic thermodynamic principles outlined above. The UN's Food and Agriculture Organization (FAO) estimates that ~ 30% of the ice-free land surface area of Earth is directly or indirectly involved in livestock production! Eating lower on the food chain, one or more of the following benefits would be likely: Not as much land and other resources raising grain to feed to animals. Overgrazing on public and private range lands could decrease. Would not have to farm or graze marginal lands as intensively More people in the world could receive an adequate diet Less fossil fuel energy (and associated emissions of CO2) would be required to produce our food.

Cultural choices may influence societies to harvest food from higher trophic levels.

Most food is harvested from low trophic levels (producers and herbivores). Systems that produce crops are more energy efficient then those which produce livestock. This is because energy is greater in proportion in the low trophic levels. Even though it is efficient to use arable systems, many cultures still use livestock as part of their farming system. Taste and cultural demand play a major role in this and the animals also provide a source protein which is essential for the human diet. Animals are also used as working animals in some cultures.

Benefits of Contour Stripcropping?

Profits Soil Erosion Water Quality Wildlife

Socio-economic, cultural, ecological, political and economic factors can be seen to influence societies in their choices of food production systems

Social influences on food intake refer to the impact that one or more persons has on the eating behavior of others, either direct or indirect, either conscious or subconscious. The relationship between low socio-economic status and poor health is complicated and is influenced by gender, age, culture, environment, social and community networks, individual lifestyle factors and health behaviors. There are clear differences in social classes with regard to food and nutrient intakes. Low-income groups in particular, have a greater tendency to consume unbalanced diets and have low intakes of fruit and vegetables. Education level and income determine food choices and behaviors that can ultimately lead to diet-related diseases. The origins of many of the problems faced by people on low incomes emphasizes the need for a multidisciplinary approach to targeting social needs and improving health inequalities.

Benefits of Contour Farming?

Soil Erosion Water Quality

Human activities that can reduce soil fertility include deforestation, intensive grazing, urbanization and certain agricultural practices (such as irrigation and monoculture).

Soil degradation is the decline in quantity and quality of soil. It is also erosion by wind and water, biological degradation (loss of humus and plant or animal life), physical degradation (loss of structure, changes in permeability), chemical degradation (acidification, declining fertility, changes in pH, salinity) Human activities such as overgrazing, deforestation, unsustainable agriculture and irrigation cause processes of degradation. These include soil erosion, toxification and salinization. Desertification (enlargement of deserts through human activities) can be associated with this degradation.

Soil system storages include organic matter, organisms, nutrients, minerals, air and water

Soil has matter in all three states: organic and inorganic matter form the solid state soil water(from precipitation, groundwater and seepage) form the liquid state soil atmosphere forms the gaseous state

Discuss the influences of human activities on soil fertility and soil erosion.

Soil is a non-renewable resource that once it is eroded it is not renewed. Soil erosion is the permanent change of the main characteristics of soil that could see it lose its fertility, pH, colour, humus content or structure. Soil erosion occurs naturally by wind or harsh climatic conditions but human activities include overgrazing, overcropping and deforestation. Overgrazing occurs when farmers stock too many animals such as sheep, cattle or goats on their land. The animals damage the soil surface by eating the vegetation and either digging into wet soil or compacting dry soil with their hooves. Overcropping is when the land is being continuously under cultivation and is not allowed to lie fallow between crops. This constant farming of the land reduces the soils ability to produce valuable humus for soil fertility as it is constantly being ploughed or stripped for crop growth. The soil becomes drier and less fertile. Deforestation is the cutting down of large areas of forests leaving an open, exposed landscape. Deforestation occurs for many reasons such as the sale of wood, charcoal or as a source of fuel, while cleared land is used as pasture for livestock, plantations of commodities, and settlements. The removal of trees without sufficient reforestation has resulted in damage to habitat, biodiversity loss and aridity (drying of soil).

Explain how soil can be viewed as an ecosystem.

Soil is the link between the air, water, rocks, and organisms, and is responsible for many different functions in the natural world that we call ecosystem services. These soil functions include: air quality and composition, temperature regulation, carbon and nutrient cycling, water cycling and quality, natural "waste" (decomposition) treatment and recycling, and habitat for most living things and their food. We could not survive without these soil functions. ​Billions of organisms inhabit the upper layers of the soil, where they break down dead organic matter, releasing the nutrients necessary for plant growth. The micro-organisms include bacteria, actinomycetes, algae and fungi. Macro-organisms include earthworms and arthropods such as insects, mites and millipedes. Each group plays a role in the soil ecosystem and can assist the organic farmer in producing a healthy crop. Micro-organisms can be grouped according to their function: free-living decomposers convert organic matter into nutrients for plants and other micro-organisms, rhizosphere organisms are symbiotically associated with the plant roots and free-living nitrogen fixers.

The soil system may be illustrated by a soil profile that has a layered structure (horizons).

Soils are major components of the world's ecosystems.Soil forms the Earth's atmosphere, lithosphere (rocks), biosphere (living matter) and hydrosphere (water). Soil is what forms the outermost layer of the Earth's surface, and comprise weathered bedrock (regolith), organic matter (both dead and alive), air and water. The soil interacts with the atmosphere, lithosphere, biosphere and hydrosphere. The water cycle moves through the soil by infiltration and water may evaporate from the surface. The atmosphere may contain particulate matter that is deposited on the soils and particles may blow up into the atmosphere. Rocks in the lithosphere weather to form soils, and soils at depth and pressure may form rocks. Plants in the biosphere may extract nutrients from the soils and dead plants may end up forming parts of the soil. Soils are important to humans in many ways: soil is the medium for plant growth, which most of foods for humans are grown in soil stores freshwater, 0.005% of world's freshwater soil filters materials added to the soil, keeping quality water recycling of nutrients takes place in the soil when dead organic matter is broken down soil is the habitat for billions of micro-organisms, as well as other larger animals soil provides raw material in the forms of peat, clay, sands, gravel and minerals Picture image from en.wikipedia.org Soil Horizons. O) Organic matter: Litter layer of plant residues in relatively undecomposed form. A) Surface Soil: Layer of mineral soil with most organic matter accumulation and soil life. This layer eluviates (is depleted of) iron, clay and calcium, organic compounds, and other soluble constituents. When eluviation is pronounced, a lighter colored "E" subsurface soil horizon is apparent at the base of the "A" horizon. A-horizons may also be the result of a combination of soil bioturbation and surface processes that separates fine particles from biologically mounded topsoil. In this case, the A-horizon is regarded as a "biomantle". B) Subsoil: This layer accumulates iron, clay, aluminum and organic compounds, a process referred to as illuviation. C) Parent Rock: Layer of large unbroken rocks. This layer may accumulate the more soluble compounds. R) Bedrock: The parent material in bedrock landscapes. This layer denotes the layer of partially weathered bedrock at the base of the soil profile. Unlike the above layers, R horizons largely comprise continuous masses of hard rock that cannot be excavated by hand. Soils formed in situ will exhibit strong similarities to this bedrock layer. These areas of bedrock are under 50 feet of the other profiles.

Soil conservation measures include soil conditioners (such as organic materials and lime), wind reduction techniques (wind breaks, shelter belts), cultivation techniques (terracing, contour ploughing, strip cultivation) and avoiding the use of marginal lands.

Strategies for combating soil degradation is not so common or widespread and to reduce this risk farmers are encouraged and informed about the processes and conservation methods. Farmers are in the need of beginning with extensive management practices like organic farming, afforestation, pasture extension, and benign (gracious) crop production. However to make this work policies need to be put into place. Consider conservation measures: soil conditioners (for example, use of lime and organic materials) wind reduction techniques (wind breaks, shelter belts, strip cultivation) cultivation techniques (terracing, contour plowing) efforts to stop plowing of marginal lands Trickle drip is a slow release of water from pipes under the surfaces which can reduce the loss of evaporation There are several methods farmers can use to reduce or prevent erosion. Mechanical methods are used to reduce water flow including bunding, terracing, and contour ploughing. The goal is to prevent and slow down the movement of rain water down the slopes. Vegetation cover methods use roots of crops to help bind the soil and decrease the action of wind and rain on the soil surface. Increased organic on the soil surface allows the soil to hold more water and reduce the mass, movement and erosion and stabilizing the soil structure. Soil husbandry is used to prevent damage to the soil structure. Care is taken to reduce the use of heavy machinery especially on wet soils and ploughing on soils that are sensitive to erosion. The three main ways of managing salt-affected soils is by: flushing the soil with water and leaching the salt away using gypsum and calcium sulfates to replace sodium ions on the clay and colloids reduction in evaporation losses to reduce the upward movement of water in the soil Both socio-economic and ecological factors have been ignored and integrated approach to soil conservation is needed, non-technological factors like population pressure, social structures, economy and ecological factors can determine the appropriate technical solutions.

terrestrial farming

Terrestrial farming systems are divided into two types: Commercial farming: for profit, often monoculture Subsistence farmer: produces only enough to feed their family with no sell for profit Both commercial and subsistence can be intensive or extensive farms Intensive farms: take a small area of land for a high input Extensive farms: large in comparison to the money and labour put into it

Analyse tables and graphs that illustrate the differences in inputs and outputs associated with food production systems.

Terrestrial farming systems can be divided into several types Commercial farming in which farming is for profit. This usually involves one crop Subsistence farming in which food is produced only to feed the farmer and family. No sale for profit Commercial and subsistence farming can be intensive or extensive Intensive farms generally take up a small area of land but aim to have very high outputs per unit area of land Extensive farms are usually large in comparison to the money and labor put into them

Inequalities exist in food production and distribution around the world

The United Nations Food and Agriculture Organization estimates that nearly 870 million people of the 7.1 billion people in the world, or one in eight, were suffering from chronic undernourishment in 2010-2012. Almost all the hungry people, 852 million, live in developing countries, representing 15 percent of the population of developing counties. There are 16 million people undernourished in developed countries. Chronic under-nourishment, during childhood leads to permanent damage: stunted growth, mental retardation, and social and developmental disorders. Many are also suffering from malnutrition (enough energy but not enough essential nutrients). In many MEDCs, the cost of food is relatively cheap and people choose food based on preference not nutritional need. Seasonal foods have almost disappeared as foods are readily available all year round. Modern technology and transport systems mean that foreign foods can be bought in almost any market. In LEDCs, many populations struggle to produce enough food to sustain them. Arable land is scarce. There may also be political agendas as well as simple environmental limitations on food production. Crops that are grown are often exported for profit (cash cropping) and not for the local communities. Arable land is in finite supply. There are large differences in food production in the world but distribution is the problem. Countries like USA, Canada, and Australia produce more food than they need but who should pay for it to be distributed to poorer countries in need such as Bangladesh, Sudan and Ethiopia. The political angle attached to this means that perhaps the receiving country maybe in the others debt, and prone to exploitation. Who decides who gets this food? These are issues that revolve around the topic of food distribution. The diets of MEDCs and LEDCs, differ as well. MEDCs average calorie intake is about 3314 whereas LEDCs is only about 2666 per day. As we adapt more and more of the net primary productivity on Earth to human needs, use and degrade more land, demand more meat, we must be reaching our limits. Agriculture in the LEDCs are in contrast and have low levels of technology, lack of capital and high levels of labour." Cause in imbalance food distribution Ecological: some climate and soils are better for food production Economic: advance technology and money can overcome ecological limitation (transportation of water) Socio-political: underinvestment in rural area and rapid area in LEDC; poor human health weaken available labor force

Soil ecosystems change through succession. Fertile soil contains a community of organisms that work to maintain functioning nutrient cycles and that are resistant to soil erosion.

The amount of time required for soil formations varies from soil to soil. Some soils develop more quickly than others. Phases of erosion and deposition also keep soils in a changing state. Organic matter releases releases acids and returns nutrients to the soil. Animals help break down organic matter, mix the soil, aerate the soil and add faces to the soil.

Compare and contrast the inputs, outputs and system characteristics for two given food production systems.

The systems selected should be both terrestrial or both aquatic. In addition, the inputs and outputs of the two systems should differ qualitatively and quantitatively (not all systems will be different in all aspects). The pair of examples could be North American cereal farming and subsistence farming in some parts of South‑East Asia, intensive beef production in the developed world and the Maasai tribal use of livestock, or commercial salmon farming in Norway/Scotland and rice‑fish farming in Thailand. Other local or global examples are equally valid. Picture Factors to be considered should include: inputs, such as fertilizers (artificial or organic); water (irrigation or rainfall); pest control (pesticides or natural predators); labour (mechanized and fossil-fuel dependent or physical labour); seed (genetically modified organisms—GMOs—or conventional); breeding stock (domestic or wild); livestock growth promoters (antibiotics or hormones vs organic or none) outputs - outputs, such as food quality, food quantity, pollutants (air, soil, water), consumer health, soil quality (erosion, degradation, fertility); common pollutants released from food production systems include fertilizers, pesticides, fungicides, antibiotics, hormones and gases from the use of fossil fuels; transportation, processing and packaging of food may also lead to further pollution from fossil fuels system characteristics—selective breeding, genetically engineered organisms, monoculture versus polyculture, sustainability, system characteristics - such as diversity (monoculture versus polyculture); sustainability; indigenous versus introduced crop species socio‑cultural—the Maasai cattle equals wealth and quantity is more important than quality; environmental impact—pollution (air, soil, water); habitat loss; biodiversity loss; soil erosion or degradation; desertification; disease epidemics from high-density livestock farming socio-economic factors - arming for profit or subsistence, for export or local consumption, for quantity or quality; traditional or commercial farming.The systems selected should be both terrestrial or both aquatic. In addition, the inputs and outputs of the two systems should differ qualitatively and quantitatively (not all systems will be different in all aspects). The pair of examples could be North American cereal farming and subsistence farming in some parts of South‑East Asia, intensive beef production in the developed world and the Maasai tribal use of livestock, or commercial salmon farming in Norway/Scotland and rice‑fish farming in Thailand. Other local or global examples are equally valid. Picture Factors to be considered should include: inputs, such as fertilizers (artificial or organic); water (irrigation or rainfall); pest control (pesticides or natural predators); labour (mechanized and fossil-fuel dependent or physical labour); seed (genetically modified organisms—GMOs—or conventional); breeding stock (domestic or wild); livestock growth promoters (antibiotics or hormones vs organic or none) outputs - outputs, such as food quality, food quantity, pollutants (air, soil, water), consumer health, soil quality (erosion, degradation, fertility); common pollutants released from food production systems include fertilizers, pesticides, fungicides, antibiotics, hormones and gases from the use of fossil fuels; transportation, processing and packaging of food may also lead to further pollution from fossil fuels system characteristics—selective breeding, genetically engineered organisms, monoculture versus polyculture, sustainability, system characteristics - such as diversity (monoculture versus polyculture); sustainability; indigenous versus introduced crop species socio‑cultural—the Maasai cattle equals wealth and quantity is more important than quality; environmental impact—pollution (air, soil, water); habitat loss; biodiversity loss; soil erosion or degradation; desertification; disease epidemics from high-density livestock farming socio-economic factors - arming for profit or subsistence, for export or local consumption, for quantity or quality; traditional or commercial farming. Terrestrial Systems: Intensive Charolais beef production in France: In Western Europe the Charolais beef is one of the beef brands chosen. Through selective breeding and genetic engineering bloodlines that puts weight on exist but has a low fat cover. Charolais lives under controlled conditions, they are fed with high proteins and treated with antibiotics to make sure they are healthy. Lots of energy is used in transporting and processing the finished meat. Cattle raised outdoors however grown on single monoculture ( cultivation of a single crop on a farm or in a region or country) grass land in large fields with a high stock rate. To keep the productivity of these fields going, large amounts of fertilizer are used. This intensified farming e the 1940′s with the aim of producing cheaper meat has led to habitat loss as they have been removed to make bigger fields and cases of Eutrophication have increased as excess use of fertilizers and large amounts of slurry produced in the system enter water courses. Fear of causing antibiotic resistance in human bacteria through bioaccumulation. Inputs: energy for food distribution food supplements selective breeding and genetic engineering (system characteristics) indoor rearing fertilizers to maximize grass production antibiotics and hormones Outputs: cheap meat (socio-cultural) habitat destruction to make bigger fields (environmental impact) antibiotic resistance Eutrophication

Outline the transfers, transformations, inputs, outputs, flows and storages within soil systems

There are four basic processes that occur in the formation of soils, inputs - physical movement of material within soil. outputs - occur both from the surface and from the deep subsoil. Water lost by evapotranspiration translocations - translocation of materials within the soil profile is primarily due to gradients in water potential and chemical concentrations within the soil pores. transformations - change of some soil constituent without any physical displacement. The two driving forces for these processes are climate (temperature and precipitation) and organisms, (plants and animals). Parent material is usually a rather passive factor in affecting soil processes because parent materials are inherited from the geologic world. Topography (or relief) is also rather passive in affecting soil processes, mainly by modifying the climatic influences of temperature and precipitation.

The sustainability of terrestrial food production systems is influenced by factors such as scale; industrialization; mechanization; fossil fuel use; seed, crop and livestock choices; water use; fertilizers; pest control; pollinators; antibiotics; legislation; and levels of commercial versus subsistence food production.

There are many factors that affect food production. The post-war 'second agricultural revolution' in developed countries, and the 'green revolution' in developing nations in the mid-1960s transformed agricultural practices and raised crop yields dramatically, but the effect is levelling off and will not meet projected demand At the same time, many other factors are having severe impacts on food production: water stress and desertification is reducing the amount of arable land; many pests are becoming resistant to insecticides, but many of the most effective chemical agents are now banned under environmental regulations; underdeveloped infrastructure means that losses increase further during transport and storage; consumption patterns are changing and developing nations such as India and China have an increased appetite for meat, and climate change is bringing new microbial diseases to food-growing regions along with more extreme and unpredictable weather patterns. Increases in global populations and changes in diet have put pressure on terrestrial food production systems. Arable land is becoming limited due to increasing human settlements and urbanization. Soils are becoming degraded through intensive farming. Increased agriculture has led to the loss of biodiversity as native habitats have been cleared.

Discuss the links that exist between sociocultural systems and food production systems.

This could be illustrated through the use of examples, such as: the way in which the low population densities and belief systems of shifting cultivators links with the ecosystem of "slash and burn" agriculture; the relationship between high population densities, culture, soil fertility and the wetrice ecosystem of South‑East Asia; the link between the political economy of modern urban society, corporate capitalism and agro-ecosystems. There are many factors that come into consideration as to the method and level of sustainability of food production methods. Population density/size, culture, soil fertility, and method of agriculture are some of these factors. Shifting cultivation is an agricultural system in which plots of land are cultivated temporarily, then abandoned and allowed to revert to their natural vegetation while the cultivator moves on to another plot. The period of cultivation is usually terminated when the soil shows signs of exhaustion or, more commonly, when the field is overrun by weeds. The length of time that a field is cultivated is usually shorter than the period over which the land is allowed to regenerate by lying fallow. Of these cultivators, many use a practice of slash-and-burn as one element of their farming cycle. Others employ land clearing without any burning, and some cultivators are purely migratory and do not use any cyclical method on a given plot. Sometimes no slashing at all is needed where regrowth is purely of grasses, an outcome not uncommon when soils are near exhaustion and need to lie fallow. One land-clearing system of shifting agriculture is the slash-and-burn method, which leaves only stumps and large trees in the field after the standing vegetation has been cut down and burned, its ashes enriching the soil. Cultivation of the earth after clearing is usually accomplished by hoe or digging stick and not by plough.

what are surface currents?

are moved by the wind. The Earth's rotation deflects them and increases their circular movement

renewable water

atmosphere and rivers

Measuring water pollution

biochemical oxygen demand- is a measure of the amount of dissolved oxygen required to break down the organic material in a given volume of water through aerobic biological activity by microorganisms 2.biotic indices and indicator species - [ ] Indicator species:are plants and animals that show something about the environment by their presence, absence, abundance or scarcity - [ ] A biotic index- indirectly measures pollution by assaying the impact on species within the community according to their tolerance, diversity, and relative abundance Indicator species are the most sensitive to change so they are the early warning signs that something may have changed

the water cycle

energy from solar radiation and the force of gravity drive the water cycle. the water cycle drives the world´s weather systems

Evaluate the soil management strategies of a given commercial farming system and of a given subsistence farming system.

image from en.wikipedia.org The North American Prairies and Commercial Farming The problems occurred were increasing salinity, soil erosion and loss of soil fertility. Farmers managed to reduce salinity and erosion, to reduce salinity summer fallowing or leaving bare soil for long periods were stopped or reduced. Snow fences or barriers enabled snowdrifts to pile up which provide water then they melt in. And to reduce erosion is used contour ploughing- along the contour lines instead of up and down slopes traps soil and water. Strip Cropping - growing as flax and tall wheatgrass at right angles to the wind

There are inputs of organic material including leaf litter and inorganic matter from parent material, precipitation and energy. Outputs include uptake by plants and soil erosion.

image from www.gov.mb.ca Inputs 1. Weathering Rock weathering is one of the most important long-term sources for nutrients. However, this process adds nutrients to ecosystems in relatively small quantities over long periods of time. Important nutrients released by weathering include: Calcium, magnesium, potassium, sodium, silicon, iron, aluminum, and phosphorus. ​ 2. Atmospheric Input Large quantities of nutrients are added to ecosystems from the atmosphere. This addition is done either through precipitation or by a number of biological processes. Carbon - absorbed by way of photosynthesis. Nitrogen - produced by lightning and precipitation. Sulfur, chloride, calcium, and sodium - deposited by way of precipitation. 3. Biological Nitrogen Fixation Biological nitrogen fixation is a biochemical process where nitrogen gas from the atmosphere is chemically combined into more complex solid forms by metabolic reactions in an organism. This ability to fix nitrogen is restricted to a symbiotic associations with legumes and other microorganisms. Outputs 1. Erosion Soil erosion is probably the most import means of nutrient loss to ecosystems. Erosion is very active in agricultural and forestry systems, where cultivation, grazing, and clearcutting leaves the soil bare and unprotected. When unprotected, the surface of the soil is easily transported by wind and moving water. The top most layers of a soil, which have an abundance of nutrient rich organic matter, are the major storehouse for soil nutrients like phosphorus, potassium, and nitrogen. 2. Leaching Leaching occurs when water flowing vertically through the soil transports nutrients in solution downward in the soil profile. Many of these nutrients can be completely lost from the soil profile if carried into groundwater and then horizontally transported into rivers, lakes, or oceans. Leaching losses are, generally, highest in disturbed ecosystems. In undisturbed ecosystems, efficient nutrient cycling limits the amount of nutrients available for this process. 3. Gaseous Losses High losses of nutrients can also occur when specific environmental conditions promote the export of nutrients in a gaseous form. When the soil is wet and anaerobic, many compounds are chemically reduced to a gas from solid forms in the soil. This is especially true of soil nitrogen.

water budget

is a quantitative estimate of the amounts of water in storages and flows of water cycle

what is contour stripcropping

is crop rotation and contouring combined in equal-width strips of corn or soybeans planted on the contour and alternated with strips of oats, grasses, or legumes.

Eutrophication

is when excess nutrients are added to an aquatic ecosystem

what are deep water currents

make up 90% of ocean currents and cause the conveyor belt

Optimal sustainable yield

maximizes the difference between total revenue and total cost - [ ] Has a greater saftey margin then the maximum sustainable yield - [ ] Fishing quota is often set a percentage rather than a number

Harvesting the maximum sustainable yield ?

normally leads to population decline and thus loss of resource base and an unsustainable industry or fishery - [ ] The populations dynamics are being guess rather then bring quantitatively measure (counted) - [ ] It is often impossible to know the exact size of population - [ ] Estimates are made on previous experiences - [ ] Disease may strike the population - [ ] The model does not allow for monitoring of the dynamic nature of the harvest in terms of age and sex ratio

what are ocean currents?

ocean currents are movements of water both vertically and horizontally. they are found in the deep water or on the surface

why are ocean currents important?

ocean currents have an important role in the global distribution of energy

non-renewable water

oceans, icecaps

issue with desalination?

salt is a by-product and is often return to the ocean, increasing the density of the water which then sinks and damages ocean-bottom ecosystems

sources of freshwater?

surface fresh waters (lakes,streams,resevoirs, rivers)

sustainability of freshwater resource usage?

sustainable use of resources allows full natural replacement of the resources exploited and full recovery of the ecosystems affected by their extraction and use

example of water scarcity

the danbue river basin is shared by 19 countries and 81 million people

the water cycle consists of storages of water and the flows of water between the various storages., what are they?

transfers, when it stays in the same state: -flooding -surface run-off -advection (wind blow movement) -infiltration and percolation (when the water runs into and through the soil or rocks) -streamflow current transformations, when it changes state to or from liquid water, are: -Evapotranspiration- liquid to water vapour -condensation-water vapour to liquid -freezing-into solid snow and ice the storages include the: -oceans -soil -groundwater (aquifers) -lakes -rivers and streams -atmosphere -glaciers and ice caps

ocean currents and climate?

water masses heat up and cool down more slowly then land masses as a result, land close to seas and oceans has a mild climate with moderate winters and cool summers

Evaluate strategies to increase sustainability in terrestrial food production systems.

​Altering human activity Local produce Food Labels Monitoring multi-nationals Buffer zones (nutrient run-off)

A 5.1.3 Compare and contrast the structure and properties of sand, clay and loam soils, with reference to a soil texture diagram, including their effect on primary productivity.

​Soil structure depends on: Soil texture ( the amount of sand and clay ) dead organic matter earthworm activity For optimum structure, variety of pure sizes are required to allow root prevention, free drainage and water storage. Pore spaces over 0.1 mm allow roots growth, oxygen diffusion and water movement where as pore spaces below 0.5 mm help store water. Clay: fertile in temperate locations in tropical areas clay is permeable and easily penetrated by roots nutrient deficient / easily leached in tropics The more clay present in soil the higher the force needed to pull a plough. Different soil types have different levels of primary productivity: sandy soil - low clay soil - quite low loam soil - high ​ Primary productivity of soil depends on: mineral content drainage water-holding capacity airspaces biota potential to hold organic materials *Shrinking limit: state which the soil passes from having a moist to a dry appearance. *Plastic limit: occurs when each ped is surrounded by a film of water sufficient to act as a lunricant. *Liquid limit: occurs when there is sufficient water to reduce cohesion between the peds. *Field capacity: maximum amount of water that a particular soil can hold.

Transformations include decomposition, weathering and nutrient cycling.

​The transformation and movement of materials within soil organic matter pools is a dynamic process influenced by climate, soil type, vegetation and soil organisms. All these factors operate within a hierarchical spatial scale. Soil organisms are responsible for the decay and cycling of both macronutrients and micronutrients, and their activity affects the structure, tilth and productivity of the soil.

Transfers of material within the soil, including biological mixing and leaching (minerals dissolved in water moving through soil), contribute to the organization of the soil

​Translocation involves the movement of soil-forming materials through the developing soil profile. Translocation occurs by water running through the soil transferring materials from upper to lower portions of the profile. Burrowing animals like earth worms, ants, etc., move soil materials within the profile. Burrowing animals create passage ways through which air and water can travel promoting soil development.