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    Landscape ecology.

    Ecology often assumes a similar blend of environment (homogenous) but an environment is highly differentiated. Interactions between organisms are affected by distance and landscape structure. A landscape is a mixed area composed of distinctive ecosystem patches arranged as a mosaic. Patches are the elements that make up a landscape, pattern is the arrangement and composition of patches that make up a landscape. Landscape ecology is the study of relationship between spatial pattern and ecological processes at a range of scales. Landscape ecology may also focus on larger spatial extents than traditionally examined in ecology, and often focuses on the role of humans in affecting patterns and processes.

    Elements of landscape structure

    The size, shape, composition, number and position of patches in a landscape determine the landscape structure. The background in this mosaic is called the matrix, the element that is most spatially continuous.

    How landscape develops

    Environmental variation causes patches of different ecosystems with critical temperature and moisture levels demarcating boundaries. May be abrupt substrate changes e.g. timberlines, wetlands, frost flats. Disturbance occurs patchily through landscapes and different landscape patterns can result from different disturbances. Some organisms act as ecosystem engineers and affecting landscape structure e.g. beavers, termites, disease outbreak, humans. Humans are the largest causes of changes in landscape heterogeneity.
    How landscape influences ecological processes and distribution and abundance of organisms.

    Edge Effects.

    Borders between patches include the edge zone, which if wide enough can be a habitat in its own right. Edges can be inherent, set by geographical features, or induced, created by disturbance (natural or human). Edges of patches can be influenced by the proximity of a contrasting ecosystem creating a zone that differs from the patch interior in both environment and biota (microhabitats, microclimate). Some species are edge or interior specialists. Effect of edge can extend tens of meters into the forest. This takes place over time after an edge is created. Initially there is physical damage and an exchange of energy, matter and species. Increased productivity, evapotranspiration, nutrient cycling, decomposition and dispersal lead to increased sapling and understory density.

    Compositional differences occur between edges and interiors (Young and Mitchell 1994 at Warkworth). 33 pecies on edge, 23 in interior, 12 edge only, 2 interior only. Canopy dominants changed.


    Many forest ecosystems are fragmented by humans agricultural development. Natural vegetation has changed from being the matrix to the patch. This has reduced the area, and increased the proportion of edge habitat in the remaining patches with subsequent changes on biota. Most NZ forests are fragments isoalated for at least 80-100 years. The only remnants of indigenous biodiversity in some lowland rural landscapes. Most are privately owned and degraded through understory grazing by farm animals and canopy possum browsing. Many are being restored > 300 covenants in 2009.
    Some bird species vary in sensitivity to habitat size, isolation and condition. Focal species approach suggests using most sensitive species to determine management guidelines for landscapes. Near Canberra, hooded robin were deemed most sensitive, fragment size minimum 10 ha, and gaps between patches no more that 1.5 km.
    The total proportion of remnants in a landscape that will continue to support local habitat opportunities including immigration and seed recruitment from other areas maintaining biodiversity is not known. A threshold may exist where landscape scale connectivity is eroded and biodiversity is dependent on remnant patch size.

    Habitat corridors.

    Connect two patches across a matrix. Often proposed in conservation plans e.g. migration routes for ruminants. Much debate over their effectiveness. Meta analysis: increase of migration between habitat patches by 50%. More important for invertebrates non avian vertebrates and plants than birds. Highly dependent on species characteristics.
    I'm in it for the tomatoes. I been growing tomatoes for a long long time. Sometimes I get to thinking I know everything about tomatoes.
    My tomatoes make me completely delusional.


      Very informative thread, thanks for sharing


        death thread? aweosme info shit like this rocks


          Originally posted by MrFista View Post
          More Mosses: Division Bryophyta.

          All moss gametophytes have two distinct phases as the protonema (see moss life cycle picture in previous post) and the leafy gametophyte. In true mosses, the protonema cells are in a single layer, and the branching resembles filamentous green algae. Leafy gametophytes develop from bud like structures on the protonema. In some mosses the protonemata (plural) persist and assume the major photosynthetic role, and the gametophytes are minute. Protonemata are characteristic of all mosses, some liverworts, but not hornworts.

          The True Mosses: Class Bryidae.

          View Image

          The true moss gametophyte is leafy and typically upright rather than flattened as in the leafy liverworts. Three initial ranks of leaves after axial twisting resemble a spiral arrangement - like phyllotaxy, but instead the stem twists. Not so apparent in some aquatic mosses. In many species the stems of gametophytes and sporophytes have a strand of water conducting hydroid cells (dead when mature, become empty and thus useful as a pipe). In some genera, leptoids – living food conducting cells, surround the hydroids.

          Cushiony mosses (below and above). Gametophytes are erect and little branching, usually bearing terminal sporophytes.

          View Image

          Feathery Mosses. (below) Plants are creeping, leaves typically branched often superficially resembling ferns, often hanging as epiphytes from trees.

          View Image

          The Granite Mosses: Class Andreaeidae. (below)

          Occurring in mountainous or arctic regions, often on granite rocks, the genus Andreaea consist of only about 100 species. The gametophytes closely resemble true mosses but the sporophyte lacks a true seta (stem) and is raised instead on a stalk of gametophyte tissue, the pseudopodium. The spore release mechanism also differs from other mosses with 4 ‘slits’ (vertical lines of weaker cells among stronger cells) that open widely when the capsule is dry, releasing windborne spores, and closing when it is moist. A second genus found in Alaska, Andreaobryum, has one (discovered) species. It has a sporophyte with a true seta, and its capsule splits to the apex.

          View Image

          The Peat Mosses: Class Sphagnidae.

          Diverging from the main line of moss evolution very early, the genus Sphagnum holds approximately 350 species of mosses. The gametophyte stems bear clusters of branches, often five per node, resembling a ‘mop like’ head. The plants form bright green or reddish clumps in boggy ground. The leaves lack midribs and consist of large dead cells surrounded by a narrow band of green, or red, living cells. The dead cells are what gives sphagnum it’s water holding capacity (20 times the dried weight), the pores and thickenings in these readily fill with water. In living plants the dead cells keep them turgid.

          Sphagnum sporophytes are also distinctive with spherical red to blackish brown capsules raised on a pseudopodium which is part of the gametophyte as with the granite mosses.

          An estimate of 1% of the worlds soil (1/2 the land mass of the United States) is peat bog. Peat bog can have a pH as low as 4 due to sphagnum releasing H+ ions and altering their environment. Peat is the accumulation of sphagnum, as well as sedges, grasses, reeds and other plants that grow with sphagnum. Recent experimentation and microscopy by IC Mag member Microbeman shows peat is also loaded with microbial life.

          mmmmm, i love me some
          Hylocomium splendens
          otherwise known as
          Stair-step Moss
          with leaves2 - 3 mm long, oval, smooth-edged, wide base, narrows abruptly to tip. how could you resist such a BEAUTIFUL PLANT


            Dicksonia antarctica grow to 15 m (49 ft) in height, but more typically grow to about 4.5–5 m (15–16 ft) The "trunk" of this fern is merely the decaying remains of earlier growth of the plant and forms a medium through which the roots grow. The trunk is usually solitary, without runners, but may produce offsets.
            They can be cut down and, if they are kept moist, the top portions can be replanted and will form new roots.


              This is exactly what I needed; seems like everyone in this industry is just concerned with getting quick answers and knowledge only pertaining to cannabis without taking time to look deeper into the biological side of the picture; things like why and how certain nutrients, grow styles, etc... work the way they do. Keep up with the great thread!!!


                Nice 1


                  I feel enlightened right now. I wanted to add my thanks to the bunch. This is an awesome thread.


                    Originally posted by MrFista View Post
                    The Earth is 4.5 Billion years old, give or take a few days. For 600 million years there was nothing but meteoric bombardment. Imagine that. Every morning you get up and draw the curtains, bombardment again, can’t go out. Turn on the news – bombardment, the weather, more freakin bombardment, for 600 million years nothing but bombardment happening till finally, one side must have surrendered or something, and the bombardment stopped. Somewhere shortly after this time life poked a figurative cilia up, some single celled, suspected anaerobic, self replicating assembly of organic molecules, and life was born.
                    Allow me to illustrate:
                    or, if you like remixes

                    Cool stuff here. Your intro made me lol.


                      Love it!

                      Thank you for bringing some cake science to the table! Peace and love!


                        This is awesome! Thank you!
                        "He who is unable to live in society, or who has no need because he is sufficient for himself, must be either a beast or a god."aristotle
                        "Nature does nothing uselessly."aristotle
                        "Beware lest you lose the substance by grasping at the shadow." Aesop


                          "Botany For Gardeners" it's a great book that has everything about development of flowering annuals. It was cheap too. Like $10. The author is Brian Capon