PENGERTIAN
Ekologi : studi tentang tumbuhan dan hewan dalam hubungannya dengan tempat hidupnya dan lingkungan eksternalnya. Istilah penting : Oikos, “a house or a place to live in”.
Skala penyelidikan ekologi :
1. Skala individu respon individu thd lingkungan
2. Skala populasi respon populasi satu spesies thd lingkungan dgn mempertimbangkan proses yang berlangsung.
3. Skala komunitas menyelidiki komposisi dan struktur pop.
4. Skala ekosistem menyelidiki kombinasi antara komunitas dan komponen lingkungan abiotik.
ECOLOGY
1. Ecology is the study of the interactions between organisms and their environment.
The “environment” is a combination of the physical environment (temperature, water availability, wind speed, soil acidity, etc) and any influences on an organism exerted by other organisms – the biotic environment.
2. Field study of ecology :
RULE 1
ECOLOGY IS A SCIENCE
Ecology is a purely scientific discipline which aims to
understand the relationships between oeganisms and their
wider environment. It is important to segregate political and
social impacts of ecological understanding from the
RULE 2
Ecology is only understandable in the light of evolution
The huge diversity of organisms, and the wealth of variety in their morphologies, physiologies and behavior are all the result of many millions of years of evolution. This evolutionary history has left an
indelible impression on each and every individual. It is only possible to make sense of the patterns we find to day in the light of this
RULE 3
Nothing happens “for the good of species”
A very common misconception is the idea that patterns of behavior in organisms which appear to be costly to an individual occur “for the
good of the species”. This is absolutely and completely wrong. Natural selection will favor those genes which are passed on to the most
RULE 4
Genes and Environment are both important
The environment an organism finds itself in plays an important role in Determining the options open to that individual. The genes which
define
an organism’s makeup are also of fundamental importance. To
RULE 5
Understanding complexity requires models
Ecology is a complex subject, with huge variation at almost every scale –millions of species, each with considerable genetic variation, varying numbers and ever-changing behaviors in a complex and dynamic environment. To understand it, it is necessary to clearly
identify specific questions and then formulate hypotheses which can be tested. It is often very useful to frame the hypothesis in
RULE 6
‘Story-telling’ is dangerous
RULE 7
There are hierarchies of explanations
For any observationthere is often an immediate cause
that can be diagnosed. Often this causal explanation is
sufficiently informative and we need to probe deeper to
reach a fuller grasp of the situation. Even if a
phenomenon is ‘explained’ there may well be further and
deeper explanations which allow us to see the fuller
RULE 8
There are multiple constraints on organism
Whilst the total diversity of form, function &
environmental resilience exhibited by organisms is
awe-inspiring, each individual (and, to a slightly lesser extent,
each species) operates within a relatively narrow range
of constraints. Constraints fundamentally take two forms,
(i) physical and (ii) evolutionary. Evolution can never
RULE 9
Chance is important
Chance events play a critical role in ecology. The opening of
a gap in a forest canopy or the breaching of a sand dune
after a storm will have a major impact on the ecology of
the local fauna and flora, but both are unpredictable in
either time and location. The role of chance is also integral
to the evolutionary past of organisms. The important of
chance events in ecology does not mean ecological
RULE 10
The boundaries of ecology are in the mind of ecologist
Ecology is a broad science, covering both organisms and
physical environments and hence excludes little as
PELAJARI DAN BERIKAN PENJELASAN
SINGKAT DARI RULE OF ECOLOGY
TERSEBUT
DISKUSIKAN DENGAN SELURUH TEMAN
TEMAN DI KELAS UNTUK MEMBUAT SATU
RUMUSAN YANG PALING LENGKAP
• Geografi : studi tentang “the earth as the home of humanity”, “human – environment interrelation & interaction”.
Ecological analysis salah satu pendekatan dalam analisis geografi di samping Spatial analysis dan Regional Complex analysis.
Prinsip prinsip ekologi dan lingkungan sangat penting dalam analisis geografi :
1. “oikos” – “tempat hidup” organisme (tumbuhan dan hewan) dan interrelasinya dengan lingkungan.
2. “interdependensi” antar organisme dalam suatu komunitas membentuk “rantai makanan” dalam suatu siklus.
3. “rantai makanan” (food-chain) mengikuti hirarki tertentu. 4. Putusnya mata rantai biasanya akan menimbulkan masalah.
Ekosistem
danau
Siklus dalam ekosistem
Siklus enersi dalam ekosistem
• Diagram alir enersi (siklus) dalam ekosistem hutan : - dimanfaatkan oleh tumbuhan sebesar 21%
Siklus karbon secara global
• Siklus karbon dapat dijelaskan dalam proses fotosintesa tumbuhan melalui proses ekstraksi CO2 dan H2O dari lingkungan:
Radiasi matahari + nCO2+nH2O -(CH2O)n+nO2 (ketersediaan unsur chlorophyll)
Proses fotosintesa paling maksimal terjadi pada daerah katulistiwa dengan kelembaban tanah tinggi (misalnya di Indonesia).
- Indonesia memiliki keanekaragaman hayati sangat tinggi di dunia di samping Brasil.
Fotosintesis merupakan elemen kritis dalam suatu siklus carbon global.
Rantai makanan (food-chain) dalam
Ekosistem
• Diagram rantai makanan membentuk piramida yang disebut trophic level ( trophe food ):
- level 1(T1) merupakan dasar piramida terdiri dari hijauan vegetasi dengan enersi yg dikandung dalam tumbuhan.
- level 2 (T2) terdiri dari hewan pemakan tumbuhan yg disebut herbivora.
- level 3 (T3) terdiri dari hewan pemakan daging (kelompok herbivora) yang disebut hewan karnivora
- level 4 (T4) terdiri dari hewan karnivora (termasuk manusia) yaitu pemakan hewan karnivora dan semua level organisme dibawahnya - level 5 (T5) adalah kelompok dekomposer yang merubah
