Geob 102:

Fundamental & Realized Niches

- a niche is defined by a species habitat, resources available, activity patterns and interactions - fundamental niche: the theoretical limit for a species determined by the optimal requirements for all environmental factors and absence of competition. - realized niche: actual habitats where an organism is found due to interactions and limitations on resources and presence of competition. ** A realized niche is always smaller than the fundamental niche.

outcomes of natural selection

- adaptation: a dynamic, on going, life sustaining process by which living organisms adjust to environmental changes (without evolving into a new species). - speciation: set of processes by which species are differentiated and maintained; leading to cumulative changes (drift) in genetic composition (divergence and new species). - extinction: the loss of all individuals in the population of a given species, genus, family or order.

Positive Interactions

- aka. symbiosis: benefit to one or both species - Commensalism - Mutualism

propagule

- any material used to propagate an organism to the next stage in their life cycle (e.g. plants seeds, spores) - part of an organism, individual, or group of individuals required to establish a new population (via dispersal)

bio-geography vs. ecology

- both consider relationships between organisms and environment - bio-geography emphasizes *spatial* distributions (local and regional scales) and how these change over time (temporal) - focus of bio-geography is primarily on biological/ physical processes but human interactions with the biophysical environment are also addressed.

human impacts on population distribution

- foreign species is introduced on purpose by accident by humans. The species becomes non-native, introduced. - some of these introduced species can became established and are now called naturalised species - some naturalised species can spread quickly and outcompete native species. They are now called invasive species.

low latitude forest: distribution, climate and soils

- found between the Tropic of Cancer and Capricorn. - climate: wet equatorial climate; continuously warm, high precipitation, with a distinct rainy season. - soils: oxisols, fine textured; reddish orange in colour; tree removal > hard laterite layer; also intensely weathered Ultisols on older stable tropical landscapes.

Causes of Speciation

- geographic isolation: facilitates speciation by isolating populations and preventing gene flow (migration); barriers of isolation = oceans or lakes, mountain ranges, deserts. - adaptive radiation: development of new species from a single founding species, in order to foll niches; new environment(s) provide(s) opportunity for the formation of new species adjusted to different habitats

Importance of Soils

- medium for plants - holds water/nutrients for plants - makes water/ nutrients available. - site for decomposition - key role in carbon cycle - medium for building/construction

Light: influence on animals

- metabolism - pigmentation - eating habits - daily responses - reproduction - development

Temperature: influence on plants

- photosynthesis rate - flowering and life cycle events - growth - deciduous/evergreen Example: white spruce doesn't cross the US/Canada Border because it gets too war.

Biodiversity Measurement

- species composition: list of all species present in a defined area. - species richness (R): number of species per unit area (quantity) + R = number of species / unit area - species evenness: distribution of individuals among species (equitability) - species diversity: a combination of species richness and evenness. - simpsons dominance index (C): measures dominance from 0 to 1 + 1 = dominance by one or few species or less evenness. - Simpson's diversity index (D): measures diversity from 0 to 1 (a value close to 1 = high richness and/or evenness + D = 1-C

Soil Properties

- texture - structure - porosity & permeability - color - minerals - organic matter - nutrients - moisture - depth - fertility

Permafrost processes: tundra biome

- top layer of the ground thaws each year during the mild season - active layer of seasonal that - permafrost beneath prevents water from percolating into the soil - arctic desert/wetland paradokk (low precipitation but wet conditions due to abundant serface water + low evotranspiration)

tundra biome: disturbances

- tundra biom is sensitive to disturbance due to instability of ice layer: affacted by road building and construction/ - thawing permafrost can affect plant growth, water distribution in ecosystems, create localisted ground instability and destabilise infrastructure.

elements fundamental to the evolutionary process

1. Genetic Variation: traits vary among individuals with respect to morphology, physiology and behavior (basic mechanism of evolutionary change). 2. Heritability: different genetic traits are passed onto the next generation. 3. fitness: different traits confer differential rates of survival and reproduction (i.e. some better adapted to environment/ more favorable traits) RESULT OF THREE ELEMENTS: natural selection

Tundra biome: permafrost distribution

1. continuous permafrost zone: extends without gaps under all surface features and coincides largely with the tundra climate 2. discontinuous permafrost: occurs in patches separated by frost-free zones under lakes and rivers, is common throughout the boreal forests of North America and Eurasia 3. Sub-sea permafrost: formed along arctic coastlines due to ice age/ sea-level changes 4. alpine permafrost: mountainous regions, extends range southwards.

types of evolution

1. convergent evolution: evolution of similar features through independent processes (analogous features) 2. parallel evolution: evolution of different features from a common original feature (homologous features). example: Australian marsupials and north american pacentals + example: color variation in moths, like the English peppered moth. Important for camouflage. - genetic variation -> light and dark varieties - heritability -> color is genetically controlled and thus inherited - natural selection -> color determines camouflage and therefore reproductive success. OUTCOME: ADAPTATION

processes of extinction

1. disappearance of a taxonomic group due to environmental conditions (unique genome lost forever). 2. Evolution of ancestor species into a new species.

factors affecting NPP

1. light intensity/duration 2. temperature 3. water availability. 4. nutrient availability.

3 sources of genetic variation

1. mutation: permanent alteration of DNA by external or internal factors. Can be neutral, negative or positive (a potential driver of evolution). 2. Gene Recombination: in sexual reproduction, a "shuffle" of genes when forming sexual cells. 3. Gene Flow: exchange of genes between individuals, populations and species.

biodiversity: global overview

1.7 million species known to science estimated: 4 - 30 million species New species mostly belong to: terrestrial invertebrates, soil and subterranean organisms, freshwater fish & other organisms, and marine organisms

Coastal temperature rainforest: adaptations and impacts

Adaptations: - large size - long life span - shade tolerant - plant nursing - gap dynamics (not large disturbances) Impacts/disturbances: -hisotrically, more than 90% of coastal forests were more than 250 years old (old growth) - urbanization: permanent change in land cover - logging: forests remain, but with different structure and composition

Types of Ecosystems

Aquatic: - Marine - Freshwater Terrestrial: (few examples of many) - forest - littoral - riparian - subsurface - desert - irban

human influences on evolution

pesticide and antibiotic resistant population can emerge as an inadvertent human-influenced artificial selection

Geographic Range:

the entire area where a species can be found regardless of whether it is common or rare.

Genetic Fundamentals

DNA Genome Chromosome Gene Genotype Phenotype

colonization

the establishment of a new reproducing population by a propagule, in an area not previously occupied by the species (true dispersal)

Theory of Tolerance

Each and every species is able to exist and reproduce successfully only within a definite range of values for a particular environmental factor. - O : optimum level; maximum performance - R : plant grows and reproduces successfully - G : plant Grows but cannot reproduce - S : plant Survives or persists but cannot grow - T : tolerance range for that factor; beyond tolerance is lethal. Example: there are palm trees in Vancouver, but they're there not naturally. They were planted and are able to grow/survive but not reproduce.

the big five

Earths five greatest extinctions - Ordovician - Devonian - Permian - Triassic - Cretaceous - Quaternary (driven by human actions)

Habitat vs. Ecological Niche

Every organism has a *habitat* and an ecological niche: Habitat: actual place where an organism lives (like an address) Ecological Niche: a multidimensional representative of the environment in which a species can potentially survive. All the things that an organism requires to live, interact, reproduce in a habitat (a total way of life) **no two species can occupy the same ecological niche even if they can occupy the same habitat.

Generalist vs. Specialist Niches

Generalist: species that can tolerate a wide range of environmental conditions Specialist: species with a restricted gradient distributions example: - rats can survive anywhere - raccoons can adapt to varied conditions - Seothyra spiders can survive 55 degrees Celsius

NPP Terrestrial Ecosystems

NPP is the highest in tropical forests but declines in arid regions where plant grwoth is limited by moisture and at high latitudes where the growing season is shortened by low temperatures.

Light: influence on plants

Light is the primary source of energy that sustains life through *photosynthesis* - intolerant: plants that grow best in sunlight - tolerant: plant that grows best in shade Light influences on plants include: - leaf size/thickness - chlorophyll content - growth regimes + perennial (shade tolerant) + annual (shade intolerant) - life cycle (seed germination, flowering) - ecological succession in forests - deciduous/evergreen

Moisture: influence on plants

Moisture has an influence on plants: - photosynthesis - metabolism - seed germination Plant tolerance to wet-dry conditions: - xerophytes: plants that tolerate dry conditions + example: Aloe Ferox = succulent leaves for water storage. - mesophytes: plants that tolerate moderate moisture conditions - hydrophytes: plants that tolerate very wet conditions + example: Water lilies: floating leaves to maximize sun and air exposure

NPP Ocean Ecosystems

NPP in the oceans is mainly limited by nutrient availability. The warm surface water in tropical oceans prevents circulation of nutrients from the depths. Production is enhanced in temperate oceans by the seasonal overturn that brings nutrients to the illuminated surface layer. Regions of high productivity are limited to narrow coastal zones of upwelling, such as along the west coast of S. America. and SW Africa.

Overlapping niches and species interactions

Overlapping niches between species generate different types of interactions that influence the realized niche: 1. Negative interactions (cost to one or both species) 2. Positive or symbiosis (benefit to one or both species) 3. Neutral (no effect)

montane forest: adaptations and disturbances

adaptations: - fire tolerant: thick bark and scarring ability - fire adapted: serotinous cones (fire melts waxy coating and releases seeds) disturbances: example: - mountain pine beetle infestation - fire

mutualism

a biological interaction in which both organisms benefit.

parasitism

a biological interaction in which one organism feeds off the other to its detriment

community dynamics: disturbance

a discrete event changing the structure and resource availability in a community - direct - indirect examples: infestation (western hemlock looper), wind damage, flooding.

Isotherm

a line on a map connecting points with same temperature at a given time or on average over a given period

Indirect Disturbance

a non-lethal disturbance that changes resource availability to individuals.

formation class

a subdivision of biome - defined by climate soils and vegetation

dispersal

ability to move from birth site to a new site: - passive dispersal: by external forces like wind or gravity - active dispersal: by motion of the organism itself kinds of dispersal: ecological, geographical, jump dispersal

types of biomes

forest savanna grassland desert desert tundra

Soil Development Processes

aka. Pedogenic Processes 1. Enrichment: addition by organic matter, sediment, deposition or volcanic material 2. Removal: loss of material from the soil, by: - surface erosion: physical removal, or - leaching: materials dissolved in water. 3. Translocation: movement of material between horizons, mainly by: - eluviation: downward transport of fine particles (leaving sand and silt), which results in Ae horizon.. - illuviation: accumulation of clay, humus, and minerals in B horizon 4. transformation: chemical changes by: a. mineral alteration: primary --> secondary b. humification: organic matter --> humus c. mineralization: organic matter --> humus

population

all individuals of a given species in a prescribed area

Ice sheet climate

all months are below freezing, with the lowest global temperatures on Earth experienced during the Antarctic winter. very low precipitation, but snow accumulates since temperatures are always below freezing

ecosystem

all of the interacting biological and physical components of a prescribed area.

Environmental Resources

all things consumed by an organism: - what composes an ecological niche: + PLANTS NEED: - sunlight - CO2 from the atmosphere - H20 from soil - O2 from the atmosphere - nutrients from soils - space + ANIMALS NEED: - O2 from the atmosphere - H2O from the atmosphere - Nutrients and energy sources - Space

types of speciation

allopatric speciation: formation of new species through geographic isolation. sympatric speciation: development of a new species in the same geographic area through adaptive radiation. - example" cichlid fish (lake victoria, Africa): 300 species have evolved from a few ancestral species in less than 12,000 years adapted to many habitats and food types. EXAMPLE: Galapagos finches - an example of both allopatric (first) and sympatric (later) speciation

individual organism

an individual form of life, such as a plant or an animal

International Union for Conservation of Nature (IUCN)

an international organization dedicated to finding environmental solutions to various issues, famous for the publication of the IUCN Red List of Threatened Species; founded in 1948.

genome

an organism's complete set of DNA (Book of life)

seasonal migration

annual movements of organisms from one regularly occupied geographic region to another to avoid harsh conditions or for feeding and/or mating - (not true dispersal/colonization) example: Knot (Bird)

ecosystem disturbances

any situation that affects one or more of the ecosystem processes: example: - drought (water cycle) - exotic species invasion (biological functions) - dumping toxic waste that kills soil biota (decomposers) - volcanic eruption that covers leaves with ash (primary production). - air or water pollution (biological functions).

tundra biome: distribution

arctic circle to tropic of cancer

tundra formation clas

arctic tundra -> alpine tundra

dry desert

arid deserts; can be hot-dry or cold-dry

Commensalism

association between two organisms where one benefits and the other is neutral

sweepstake routes

barriers that must be crossed by rare, chance interchanges.

gene

basic unit of heredity carried and transmitted by chromosomes; associated with specific traits

agricultural (neolitihic) revolution

began 10,000 years ago in middle east, increases abandonment of nomadic & migratory lifestyles.

soil formation: biological material

biological activity: nutrient cycling and exchanges, organic matter decomposition and even soil structure is favoured by a wide range of organisms in the soil. example: insects, plant roots, fungi, microbes, burrowing animals

high latitude climates

boreal forest tundra ice sheet

nitrogen cycle

building block of life; bacteria on legume roots "fix" atmospheric nitrogen and provide it to the plant in a useful form; processes of ploughing, decomposition returns nitrogren to the soil.

population dynamics

change in the number of individuals in a population - between locations (spatial) - at one location over time (temporal)

community dynamics: succession

changes in species composition, vegetation structure and environment over time successional change can be influenced or triggered by: - plants: changes in light availability, temperature or humidity as they grow, changes in nutrients from leaf litter, biochemical effects, diseases, etc. - animals: biotic waste, feeding, seed dispersal, physical changes, etc. - differences between species: growth rates, lifespan, maximum size, etc. - new disturbances

Growth form

characteristic physical structure, size and shape of a plane or assemblage of plants. Can be perrenial or annual

Montane forest - location climate and soils

climate: continental; cold winters and hot summers, low precipitation (rain shadow); water deficit in growing season. soils: brunisols common in forests of cooler, dryer regions. Lack horizon development found in other soil orders.

coastal temperate rainforest: location, climate and soils

climate: mild and wet winters, warm and relatively dry summers (water deficit in summer) soils: generally podzols with leach Ae horizon and abundant leaf litter

tundra biome: climate soils

climate: no true summer, but there is a short mild season, otherwise temperatures are cold. Annual precipitation is small, falling mostly during the mild season. very cold, long winters with short milder season with long days; low daily but high annual temperature tange; low precipitation with mild season wetter soils: cryosols: permafrost soils: permanently frozen but have an active layer, which freezes and thaws seasonally; organic layers decay slowly and accumulate; subject to cryoturbation soil-forming processes "frost churning"

Savanna Biome: climate and soils

climate: tropical wet-dry, less precipitation than other tropical climates. Dry cooler winters, wet hotter summer soils: varying fertility; nutrient poor oxisols in wetter savannas and alfisols more common in dryer savannas.

Negative Interactions

competition: predation/herbivory: parasitism:

Savanna Biome: distribution

consists of a combination of trees and grassland in various proportions. *largest expanses in Africa and Brazil.

ecological hierarchy

definition: - describes the arrangement of living organisms in relation to each other and the environment. smallest to largest: - individual organism - population - community - ecosystem - biome - biosphere

geography

definition: the study of the evolving character and spatial organization of the earth's surface. kinds of geography: systematic, physical, bio-geography.

low-latitude forest: disturbances

deforestation: permanent conversion of forest to non-forest area. main causes of deforestation: - logging - cattle ranching - agricultural intensification - fires - fuelwood/charcoal harvesting - roads -amazonian deforestation relates to complex cycles of degradation (decrease in productivity of an environment through depletion of resources) and marginalisation (displacement of societies most disempowered groups into ecologically vulnerable spaces and/or economically constrained roles)

DNA

deoxyribonucleic acid is the molecule responsible for encoding the genetic instructions used in the development and functioning of living organisms

formation

describes community in relation to a specific

Tropic Heirarchy

describes the position of organisms in a food chain. top to bottom: + Heterotrophs - Carnivores (tertiary consumers) - Omnivores (secondary consumers) - Herbivores (primary consumers) + Autotrophs - Photosynthesis (producers) +Heterotrophs - soil (decomposers)

Soil Classification System

developed to suit its soils, based on soil properties and emphasis on the recognitions of horizons and subhorizons. example: podsol - found in forests in cool, moist regions where abundant precipitation causes pronounced leaching - one of the most common soils in British Columbia. - podsol formation involves decomposition of organic matter and transformatin of primary minerals: 1. leaves add organic matter to litter layer. 2. humification follows as leaves decompose > dark humus layer. 3. leaching of organic acids > bleaching in ash-grey subsurface (Ae) eluviated mineral soil horizon. 4. redisposition of organic matter in darker coloured mineral soil horizon (B).

ecological dispersal

dispersal within the geographic range

community distribution

distribution of series of different communities in space based on topography and soils (toposequence)

Direct Disturbance

disturbance causing death, increasing space for survivors

sclerophyll forest

dry climates with long summer droughts (e.g. mediterranean) generally smaller trees, thick barks, small leaves; evergreen

desert biomes: climate and soils

dry tropical deserts: hot summers, moderate winters, highest annual/daily temperature ranges; very low precipitation, high evapotranspiration cold dry deserts: higher elevation or continental; more moderate temperature range, low precipitation; high water deficit CLIMATE: transitions between extreme arid, semi arid, and wet-dry climates in africa. Semi-arid regions have a short wet season wher the ITCZ is nearby during the high sun season Soils: variable from fine clay soils to coars sandy, mainly airidisols (soils of dry climates, low in organic matter and often having subsurface horizons of carbonate mineral or soluble salt accumulation) and entisols (soils lacking horizons, very dry areas, usually because their parent material has accumulated only recently.

biomass

dry weight of living organic matter in an ecosystem within a designated surface area. (e.g. grams per square meter, tonnes per ha.)

ecosystem distribution

ecoregions: a geographic grouping of landscapes, each comprised of a mosaic of ecosystems.

ecosystem services

ecosystem services are the benefits that human beings derive from a healthy ecosystem.

importance of forests

ecosystem services: - watershed services (water purification and provision) - atmosphere and climate effects ( a major CO2 sink, increases rainfall in some areas. biggest contributor of oxygen to the atmosphere. - soil maintenance and protection (soil production and recycling of nutrients; reduction of soil erosion) - disturbance regulation: protection from storm damage, especially in coastal areas. - food and habitat form biodiversity: a rich storehouse of genes that might prove useful to imrpove our crops or provide as yet undiscovered medicines. economic value: - goods: provides many of the basic goods we depend on (food, fuel, building materials, other products suchs as rubber and cork, raw material for paper and other industrial products, medicines) - jobs, recreation and ecotourism *forests provide so many ecosystem services and economic and sociocultural benefits that human needs are often pitted against forest conservation goals.

Environmental Sources

environmental factors influencing life: - global climate - micro-climate - soil & landforms

Irruption

episodic explosions in the population size and geographic ranges of organisms example: desert locust

low-latitude rainforest

equatorial wet climate; tall dense trees with lianasand epiphytes, diverse and evergreen.

Theory of Evolution

evolution: genetically-controlled changes in physiology, anatomy, and behavior that occur to a taxonomic group over time. Evolution is the mechanism that resulted in the thousands of species that live on Earth (diversity)

habitat destruction

examples: conversion of wild habitat to lands for agriculture, or the harvesting of resources such as trees is the main cause of species endangerment

geographical dispersal

expansion of geographic range example: Armadillo - South America --> North America - Spread naturally through geographical dispersal and introduced by introduced by humans (invasion)

carbon cycling

fate of carbohydrates in plants: - direct energy source - store for later use - convert to other carbon compounds - organisms in food webs pass the carbon on.

Micro-climatic Influence

fine-scale environmental regime - micro-climatic data are critical for accurate assessment of species distribution and vulnerability to climate change.

grasslands: climate and soils

focus: canadaian praries climate: continental with variable daily/annual temperature range; relatively low precipitation; distinct wet-dry season (dry summer); enough rainfall to support grass but not trees. soil: temperature grassland soils usually deep and dark. often chernozems with thick fertile upper layer, nutrient rich from the growth and decay of deep, many branched grass roots.

needle leaf forest

generally colder climates, dominated by conifers, mostly evergreen kinds of needle leaf forests: - coastal temperate rainforest - montane forest - boreal forest

genotype

genetic constitution of an individual organism

biodiversity hotspot:

geographic areas in which biodiversity is especially high, with at least 0.5% of 1500 species of endemic vascular plants, and with 70% loss of primary vegetation through human impact.

Invasion

geographical dispersal caused by the introduction of exotic species by humans example: European starling - Europe --> North America - introduced by humans = invasion example: purple loosestrife plant - eurasia --> north america - invasion

desert biome: animal characteristics

granivory: (the consumption of seeds) rather than herbivory (the consumption of leaves) is at the base of the food chain in most deserts, as those few plants that maintain leaves during dry spells usually endow them with toxic conmpounds or protect them with spines. xerocoles: (animals adapted to living in deserts) include those: primarily active at night (nocturnal) or during dawn and dusk (crepuscular); efficient at storing/conserving water; residing in burrows for cooler microclimate; avoiding sweating

grassland biome: distribution

grasslands occur in midlatitude and tropical/sub-tropical zones with pronounced seasonal variations in climate tropical grasslands: rainy/dry seasons, warm year round (savanna grasslands) temperate grasslands: seasonal climate (cold winters/hot summers) many species of perennial plants underlain by fertile soils (prairies, pampas) cold grasslands: cold most of the year, very short growing season, ultrathin layers of soils

savanna biome: disturbance

grazing: savannas are home to largge herds of migratory, grazing ungulates and their predators. can lead to desertification. fire: natural and anthropogenic - fire frequency: 2 - 10 years - fire susceptibility: during spring drought (end of winter dry season)

species

group of individuals that are morphologically similar and can interbreed freely under natural conditions, producing fertile offspring.

community

group of populations of multiple species that live and interact in a prescribed area at a specific time. an assemblage of populations of different species living in the same place at the same time and interacting with each other.

coastal temperate rainforest: vegetation characteristics (high productivity)

growth forms: - trees, shrubs, herbs, epiphytic bryophytes - large trees and multiple canopy layers Common species: - douglass fir - sitka spruce - western hemlock - western red cedar - grand fir

Montane forest: vegetation - momderate productivity

growth forms: trees, shrubs, herbs, epiphytes, bryophytes -generally smaller trees and less structural complexity than coastal forests. COmmon species: - douglass fir - trembling aspen - lodgepole pine - white spruce - engelmann spruce - subalpine fir

human influence on evolution

humans directly affect the evolution of a population through genetic modification and artificial selection (e.g. domestic pets, farm animals and plant/crop species).

tundra biome: landscape

ice wedges: form where ice accumulates in deep cracks in the sediment and undergoes seasonal freeze-thaw cycles over times thermokarst landscape and lakes: - freeze-thaw action of the soil also results in thermokarst -thermokarst lake formation results from melting of ice and settling of ground.

gross and net photosynthesis

in plants, photosynthesis must be larger than respiration for plants to survive in the long term. - gross photosynthesis: total amount of carbohydrates produced by photosynthesis. - net photosynthesis: gross photosynthesis minus respiration (total amount of carbohydrates stored after using some as energy sources for metabolism). + net photosynthesis rate rises rapidly as light intensity and temperature increase but it then decreases as high light intenity heats leaves & increases respiration > offsets gross production

role of humans in ecological systems

individual organism/populations: artificial selection, genetic engineering communities/ecosystems: habitat fragmentation and destruction; degradation of ecosystems biome/biosphere: air pollution in biosphere.

competition

interaction between organism or species in which the fitness of one is lowered by the presence of another

species composition

lists of all species that exist at a location (can be classified into plants, mammals, insects, etc.)

extinction

local extinction: disappearance of a taxonomic group in one ore more geographic areas, but not it all global extinction: loss of a taxonomic group over its entire range of distribution. *extinction is the fate of all species: 98% of species that have ever lived on Earth are now extinct. - ex. woolly mammoth, sabre-toothed cat, dodo, north american buffalo.

jump dispersal

long-distance dispersal (infrequent) example: Cattle Egret - africa --> Americas - natural jump dispersal, then colonization + diffusion assisted by domestic cattle.

forest formation class

low latitude rainforest -> subtropical evergreen forest -> monsoon forest midlatitude deciduous forest -> sclerophyll forest -> needleleaf forest

thornttree semi-desert

low-latitude; tropical and subtropical deserts

soil properties: minerals

mineral: natural inorganic substance with a defined chemical composition and atomic structure Mineral fraction of soils is composed of: - primary minerals: larger, unaltered fragments from bedrock or parent material; mainly quartz and silicates. Secondary minerals: smaller particles resulting from chemical weathering or mineral alteration; mainly clay minerals; key to soil fertility because they can hold essential nutrients.

midlatitude deciduous forest

moist continental climate with adequate precipitation, warm summers & cool winters; mostly broadleaf, deciduous

subtropical evergreen forest

moist subtropical climate, mild winter, abundant rain; mostly broadleaf, evergreen

Moisture: influence on animals

moisture has an influence on all animals: - all functions example: - invasive goats can drink sea water in the Galapagos Islands - Kangaroo Rats can obtain all their water from dry foods. They don't urinate, do not sweat; active at night.

hunter-gatherer existence:

nomads wandering from place to place in small family groups; took advantage of changing opportunites; relatively small population but fundamentally altered the environment through fire and hunting (sometimes to extinction)

Soil properties: nutrients

nutrients come from parent material and/or mineralized organic matter but must be dissolved in H2O for plant absorption macronutrients: - primary = Nitrogen (N), phosphorus (P) and potassium (K); - secondary = calcium (Ca), magnesium (Mg), and sulfur (S). Micronutrients: essential but very small quantities required. - boron (B) - copper (Cu) - Iron (Fe) - chloride (Cl) - manganese (Mn) - molybdenum (Mo) - zinc (Zn)

soil properties: organic matter

organic matter: partially decayed remains of living organisms - humus: very fine and amorphous organic matter; major source of nutrients; contributes to improve soil structure and nutrient retention. - humification: transformation of coarse organic matter into humus. - mineralization: transformation of organic matter into inorganic minerals.

Carbohydrate

organic molecule consisting of carbon (C) hydrogen (H) and oxygen (O), which constitute the primary source of energy for living organisms H2O + CO2 + light energy = CxH2yOy +O2 soil + atmosphere + sun = plant + atmosphere

ecosystem processes

organisms in an ecosystem interact with the physical environment such that a flow of energy leads to an exchange of materials (water cycling, nutrient cycling) between living and non-living parts

food chain/web and energy flows

organization of an ecosystem into steps or levels through which energy flows as the organisms at each level consume energy stored in the tissues of organisms of the next lower level. example: energy flows in a salt-marsh (coastal ecosystem flooded by tides, with salt tolerant plants) 10 to 50% of energy can be transferred from one level to another. the rest of the energy is lost in respiration, heat exchange, metabolism and tissue building.

soil structure: porosity & permeability

porosity: proportion of volumetric space between solid particles (low density = high porosity) permeability: refers to how well water flows through a material, controlled by porosity and pore connectivity. porosity and permeability are fundamental for plant growth; plants need air (respiration) and water in pores.

photosynthesis

process by which plants and other organisms convert solar energy to chemical energy (production of carbohydrate by union of water with carbon dioxide while absorbing light energy).

natural selection

process by which the genes for genetically-controlled traits become more common in a population over time because individuals with those traits are re-productively more successful than other.

grasslands: vegetation characteristics

productivity: variable, depending on precipitation and water balance; limited by soil moisture in dry period growth forms: herbs and forbs (broad-leaved herbs in sunflower and legum families) - trees only occur in riparian zones - streamside forests. dominant vegetation types: sod (turf) grasses: below ground sttems (rhizomes) grazing tolerant bunch grasses: erect stems in clusters, less grazingtolerant. moist tall-grass prairie contains a rich diversity of herbs, such as the pruple-flowered blazing star; in drier mized prairie, herbs such as the yellow prairie cone flower and occasional colour.

Savanna biom: vegetation

productivity: variable, depending on precipitation and water balance; limited by soil moisture in dry period. Growth forms: trees, shrubs and herbs adapted to moisture extremes, especially drought, including xerophytic species. example: savanna woodlands - open forest, widely spaced trees with grass understory; variable mixture of woody and herbaceous plants. rain-green vegetation: produce leaves and flowers during the wet season

desert biome: vegetation

productivity: very low growth forms: herbs, shrubs, tree-like cacti phreatophytes: plants with long tap roots to access groundwater xerophytes: plants adapted to drought by: - water storage (succulents), desiccation-tolerant. - spines protect against herbivores - reduced water loss due to small, waxy leaves - shiny surfaces or white hairs -> high albedo -> reduce temperature - deciduous leaves nurse plants: drought-tolerant plants create microclimate suitable for other species (important for succession) ephermerals: short life-cycle triggered by precipitation; adaptation for quick-use of resources when available; myriad propagules, seeds persist during drought to continue life-cycle wen conditions improve key role in desert food chain.

types of ecosystem services

provisioning: production of food, fuel or water, etc. regulating: climate control, water purification, etc. supporting: photosynthesis, soil formation cultural: e.g. spiritual, aesthetic, recreational benefits.

Ecological niches and distribution

range limits of species and patterns of distribution within that range are defined by interacting biotic and abiotic factors. example: leather flower has a highly specific ecological niche.. clusters on limestone prairies, thieves in full sun/part shade on alkaline, well drained soils, adapted to 500-600 mm precipitation zone.

Net Primary Production (NPP)

rate at which carbohydrate is accumulated in the tissues of plants within a given ecosystem VARIES among ecosystems: - wetlands > forests > prairies > deserts

habitat fragmentation

reduces usable habitat; many speices have minimum space requirements and will not move between the patches that remain (core species) while others are adapted to life at the juncture of two habitats (edge species)

growth form

refers to structure of trees, shrubs, herbs, epiphytes, lianas and bryophytes.

savanna formation class

savanna woodland -> thorntree-tall grass savanna

desert formation class

semi desert -> thorntree semi desert -> dry desert

phenotype

set of an organisms observable characteristics (genetics + environment)

community structure.

shows both species composition and growth forms in a particular forest community. example: - canopy layer: upper layer formed by mature tree crowns and including other organisms - understory layer: plant life growing beneath the forest canopy, such as shrubs, herbs and mosses. (generally shade tolerant).

monsoon forest

similar to low-latitude rainforest but deciduous due to extreme dry seasons

taxa

singular: taxon groups used for classifications

diffusion

slow extension of range over time (populations, longer term) example: Oak Trees - Natural diffusion in Great Britain - slow diffusion after glaciation

Taxonomy Hierarchy

small to large: - species - genus - family - order - class - phylum - kingdom

Soil Components

soil = the uppermost layer of earth's crust constituted by dynamic natural material made of fine mineral and organic particles pedology: study of soils. five key components: 1. minerals 2. organic matter 3. biota 4. air 5. water

soil properties: colour

soil color: indicative of composition and chemistry - dark: high in organic matter - white/pale: silica and aluminum oxides - reds and yellows: iron oxides and minerals

Soil Properties: Depth

soil depth: depths to which the roots of a plant can readily penetrate in order to reach water and nutrients.

soil properties: fertility

soil fertility: the sum of characteristics that determines the soil's capacity to sustain life. It relates to nutrient exchange capacity, organic matter, pH, structure, moisture retention, total depth and biological activity.

soil development: horizons

soil horizons: distinct horizontal layers in the soil's cross-section, with specific soil properties (texture, strcture, color, composition, etc.) Top to bottom: O: pure organic matter - L: leaf litter - F: fibric material - H: humus A: mineral soil with organic matter influence, rich in biological activity - Ah: high humic influence, nutrient rich, high biological activity. - Ae: A with removal of minerals and organic matter. B: mineral soil that has undergone sufficient changes to be different from parent material. C: weathered parent material little affected by soil forming processes. R: consolidated bedrock.

Soil Properties: Moisture

soil moisture is the amount of water present in the soil at any iven time (expressed as the fraction between mass of water and weight of solids) Soil water is a critical resource needed for plant growth. - amount available at any given time is determined by soil water balance (includes gain, loss and storage) - water stored in soil water zone is increased by recharge during precipitation (P) but decreased through evapo-transportation (E) - Surplus water is disposed of by downward percolation to the groundwater zone or by surface flow.

soil properties: structure

soil structure: how soil grains are grouped together in larger aggregates. aggregate form influences: - size of pore spaces & flow of water, gases, pollutants, etc. - growth of plants (root penetration, aeration, etc.)

soil properties: texture

soil texture: descriptive property of the mineral portion of the soil based on varying proportions of sand, silt and clay. Soil texture determines capacity of soil to retain, conduct and release water. Soil particles are classified according to size (largest to smallest): gravel -> sand -> silt -> clay -> any smaller and theyre called *colloids*

Temperature: influence on animals:

some animals are *cold blooded* (amphibians, reptiles, fish, insects), and some are *warm blooded* (mammals, birds) Temperature has an influence on (animals): - metabolism - growth - reproduction - migration example: Eastern Phoebe = range from texas border to the tip of Tenafly because the temperature is warm enough there.

agricultural transformation of maintaining land/soil fertility:

spreading animal manure on the fields and crop rotation with legumes planted for 3 out of 5 years

natural vegetation

stable, mature plant cover characteristic of a given area of land surface, largely free from the influences and impacts of human activities.

taxonomy

sub-discipline of biology concerned with classification and naming organisms based on shared characteristics.

biome classification (common names and synonyms)

taiga: refers to the boreal forest, a subdivision of the needleleaf forest. steppe/prairie/pampa: transitional formation between savanna and forest, consisting of widely spaced trees with canopy coverage from 25-60% shrubland/scrubland: formation dominated by shrubs, which could be a transition between anytype of biome and sometimes classified as a separate biome.

grassland formation class

tall-grass prairie -> short-grass prairie

Respiration

the chemical reaction that breaks the high-energy bounds of carbohydrates to release energy for an organism's metabolism - opposite of photosynthesis; all organisms respire. plant + atmosphere = exhale/transpiration + biologically usable energy.

bio-geography

the distribution and dynamics of organisms (plants and animals) and their environments and the processes influencing these.

biodiversity

the number, variety, and variability of living organisms. It is often simply defined as the number of different species that live in a give geographic area; the greater the number of species, the greater the biodiversity.

physical geography

the part of systematic geography that studies the natural processes that provide the physical setting for human activities

predation/herbivory

the preying of one animal against others

population density

the relative abundance of a species within its geographic range

Habitat

the specific environment in which a species can be found

systematic geography

the study of physical, economic, and social processes that differentiate the Earth's surface into places.

biogeography

the study of the distributions of organisms at varying spatial/temporal scales and the processes that produce these distribution patterns.

soil processes: formation and development

the type of soil that forms and develops in a region is a function of these five main factors: - organisms - topography - time - climate - parent material

Chromosome

threadlike structures containing DNA within cells, upon which genes are arranged. (chapter in a book)

biosphere

totality of all living things on Earth i.e. sum of all biomes, ecosystems

semi desert

transitional; from tropical midlatitude zones

tundra biome: vegetation

tundra = "treeless land" productivity: very low, limitedby cold temperature, short growing season and permafrost patters: growth in pockets/polygons to take advantage of soil/moisture conditions; moisture adapted plants in peatlands (decaying organic matter under conditions of permanent water saturation) growth forms: herbaceous plants (grasses, sedges) bryophytes (mosses) lichens some small shrubs. adaptations: - dwarf growth to withstand wind/ice - drought resistance/dormancy (mosses/lichens) - 99% perennial; growing season too short for annuals - fast growth species take advantage summer sunlight - short roots adapted to active layer.

green revolution

use of intensive methods, new crops and chemical fertilizers to greatly increase world agricultural output after WWII benefits: produced dramatic increases in yields enabling LDCs to keep pace with population growth costs: displaced natural cycle of fertility with a system reliant on chemicals & fossil feuls; need for legums/ manure to keep fertile declined sharply; monoculture and loss of species diversity resulted as did environmental degradation

low-latitude rainforst: vegetation and ecosystem services

vegetation: high productivity, plant growth throughout the year, tall, closely set trees; crows of the trees arranged in 2-3 layers with vary levels of shade tolerance growth forms/adaptations: large evergreen leaves, emergent species with wide buttress roots for support, woody lianas and epiphytes. example: Amazon Rainforest - houses at least 10% of the worlds known biodiversity, including endemic and endangered flora and fauna. - important role as a global carbon sink

biome

very large areas of the Earth's surface that have similar climate and vegetation

Wind: Influences on Life

wind is another key climatic factor influencing vegetation structure, especially in highly exposed areas, and also acting as a dispersal vector for seeds to help plants reproduce

facilitators and inhibitors of dispersal

windblown fruits, adherent fruits, fleshy fruits, PASSIVE DISPERSAL CORRIDORS: - regions of similar climate and vegetation structure that facilitate dispersal. BARRIERS: - elements that inhibit species from dispersing, resulting from biotic interactions or physical obstacles.