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Biomes. A distinct ecological community of plants and animals living together in a particular climate is called a "biome. The concept of an ecosystem.
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Biomes A distinct ecological community of plants and animals living together in a particular climate is called a "biome.
The concept of an ecosystem An ecosystem consists of the biological community that occurs in some locale, and the physical and chemical factors that make up its non-living or abiotic environment.
Organisation within an ecosystem population community habitat niche
Niche A given animal or plant lives in a particular place, is active at particular times and eats particular things, and these factors define its ecological niche. The environment is divided into millions of ecological niches, each of which represents a potential 'home' for life. Animals and plants will always try and take advantage of new opportunities, and so will always attempt to make a 'home' in an empty niche. In general, only one animal or plant can occupy a particular ecological niche - when two organisms try to occupy the same niche they will compete for the same resources, and one will always out-compete the other. However, when a niche becomes vacant - for example when the species which occupied it becomes extinct - there is a race to try and fill it. Mass extinctions open up a multitude of niches, and there is an evolutionary explosion as animals and plants adapt to fill the vacant 'homes'. As the Earth's environment changes over time some niches may be destroyed, driving the species which occupied them to extinction - they literally lose their ecological home.
Physical factors temperature humidity water salinity light pH soils nutrients Wind
temperature The whale is normally seen in the deep northern Atlantic. Scientists have said fluctuating ocean temperatures, predators, lack of food and even sonar from ships can send whales into waters that are dangerous for the mammals
salinity Concentration of dissolved salts found in a sample of water. Measured as the total amount of dissolved salts in parts per thousand. Seawater has an average salinity of about 34 parts per thousand (ppt).
pH Scale used to measure the alkalinity or acidity of a substance through the determination of the concentration of hydrogen ions in solution. A pH of 7.0 is neutral. Values below 7.0, to a minimum of 0.0, indicate increasing acidity. Values above 7.0, to a maximum of 14.0, indicate increasing alkalinity.Soil pH (a measure of the acidity or alkalinity of the soil)ﾊﾊ･Soil pH is one of the most important soil properties that affects the availability of nutrients. Macronutrients tend to be less available in soils with low pH.Micronutrients tend to be less available in soils with high pH.Lime can be added to the soil to make it less sour (acid) and also supplies calcium and magnesium for plants to use. Lime also raises the pH to the desired range of 6.0 to 6.5.In this pH range, nutrients are more readily available to plants, and microbial populations in the soil increase. Microbes convert nitrogen and sulfur to forms that plants can use. Lime also enhances the physical properties of the soil that promote water and air movement.
soils Soil Texture (the amount of sand, silt, clay, and organic matter in the soil). Soil texture affects how well nutrients and water are retained in the soil. Clays and organic soils hold nutrients and water much better than sandy soils. As water drains from sandy soils, it often carries nutrients along with it. This condition is called leaching. When nutrients leach into the soil, they are not available for plants to use.An ideal soil contains equivalent portions of sand, silt, clay, and organic matter. Soils across North Carolina vary in their texture and nutrient content, which makes some soils more productive than others. Sometimes, the nutrients that plants need occur naturally in the soil. Othertimes, they must be added to the soil as lime or fertilizer.
nutrients Non-Mineral Nutrients The Non-Mineral Nutrients are hydrogen (H), oxygen (O), & carbon (C). These nutrients are found in the air and water. In a process called photosynthesis, plants use energy from the sun to change c carbon dioxide (CO2 - carbon and oxygen) and water (H2O- hydrogen and oxygen) into starches and sugars. These starches and sugars are the plant's food. Photosynthesis means "making things with light"
The 13 mineral nutrients, which come from the soil, are dissolved in water and absorbed through a plant's roots. There are not always enough of these nutrients in the soil for a plant to grow healthy. This is why many farmers and gardeners use fertilizers to add the nutrients to the soil. The mineral nutrients are divided into two groups: macronutrients and micronutrients. Macronutrients Macronutrients can be broken into two more groups: primary and secondary nutrients. The primary nutrients are nitrogen (N), phosphorus (P), and potassium (K). These major nutrients usually are lacking from the soil first because plants use large amounts for their growth and survival. The secondary nutrients are calcium (Ca), magnesium (Mg), and sulfur (S). There are usually enough of these nutrients in the soil so fertilization is not always needed. Also, large amounts of Calcium and Magnesium are added when lime is applied to acidic soils. Sulfur is usually found in sufficient amounts from the slow decomposition of soil organic matter, an important reason for not throwing out grass clippings and leaves.
Micronutrients Micronutrients are those elements essential for plant growth which are needed in only very small (micro) quantities . These elements are sometimes called minor elements or trace elements, but use of the term micronutrient is encouraged by the American Society of Agronomy and the Soil Science Society of America. The micronutrients are boron (B), copper (Cu), iron (Fe), chloride (Cl), manganese (Mn), molybdenum (Mo) and zinc (Zn). Recycling organic matter such as grass clippings and tree leaves is an excellent way of providing micronutrients (as well as macronutrients) to growing plants.
Relationships of living organisms • producers • consumers • food chains and webs • competition • predation • pollination • dispersal • vegetational succession
consumers Consumers get their energy from the carbon bonds made by the producers. Another word for a consumer is a heterotroph. Based on what they eat, we can distinguish between 4 types of heterotrophs: consumer trophic level food source Herbivores primary plants Carnivores secondary or higher animals Omnivores all levels plants & animals Detritivores --------------- detritus
competition 2 species compete for the same resource if there is not enough to support both. Examples: A Douglas Fir & Western Hemlock grow together in the mixed conifer forests of Oregon, competing for minerals, water, and light. A scrub jay and a gray squirrel compete for nuts and seeds within the oak forest.
predation A consumer feeds on another consumer. Examples: The cougar is a predator of black-tailed deer. The great white shark is a predator of harbor seals.
pollination Pollination is an important step in the reproduction of seed plants: the transfer of pollen grains (male gametes) to the plant carpel, the structure that contains the ovule (female gamete).
dispersal The movement of organisms from one place to another is called dispersal. Whirling Nut (Gyrocarpus)
Vegetational succession SuccessionDirectional cumulative change in the types plantspecies that occupy a given area, through time.
Energy flows photosynthesis respiration food chains food webs
respiration Glucose + Oxygen = Carbon Dioxide + Water + Energy Aerobic respiration is the release of energy from glucose or another organic substrate in the presence of Oxygen. Strictly speaking aerobic means in air, but it is the Oxygen in the air which is necessary for aerobic respiration. Anaerobic respiration is in the absence of air.
Food chains A food chain is the path of food from a given final consumer back to a producer. For instance, a typical food chain in a field ecosystem might be: grass ---> grasshopper --> mouse ---> snake ---> haw
Nutrient cycling carbon cycle nitrogen cycle
Nitrogen cycle Biological Fixation Legumes, a special group of plants, are able to make or "fix" nitrogen. Special bacteria live on the roots of legumes. The bacteria receive "food" in the form of carbohydrates from the plants. In return, the bacteria use elemental nitrogen (N2) and change it to organic forms of nitrogen that the plant can use.
Resource potential biodiversity as a genetic resource and as a food base
Biodiversity as a genetic resource Wild varieties possess genetic resistance to pests, therefore represent a form of biological insurance. Monocultures are susceptible to pest attacks. Many major drugs come from tropical plants. Undiscovered drugs may be found.
Biodiversity as food base Plant species need to be maintained as a potential source of food.
