IMPACT OF HUMAN ACTIVITIES IN
AN ECOSYSTEM
For SCIENCE Grade 8
Quarter 4 / Week 7
1
FOREWORD
This self – learning kit will serve as a guide on
how to demonstrate an understanding of the oneway flow of energy and the cycling of materials in
an ecosystem and identify the different human
activities that affect the ecosystem. Students shall
be able to enumerate the suggested ways to
minimize human impact on the environment. The
latter part of this learning material shall allow
students to propose a plan on how to help in
conserving and protecting the environment.
2
OBJECTIVES:
K:
S:
A:
Identify the different human activities that affects the
ecosystem
Enumerate suggested ways to minimize human impact on
the environment
Propose a plan on how to help in conserving and
protecting the environment.
LEARNING COMPETENCY
Determine how do human activities affect the Ecosystem
and suggest ways to minimize human impact on the environment.
(S8LT-IVj-25)
I. WHAT HAPPENED
dreamstime.com
3
PRE-TEST
Modified Multiple Choice
DIRECTIONS: Read the following questions and choose the correct
answer from the box provided. Write your answers on your
notebook/paper.
Eutrophication,
Monoculture,
Insecticide and Pesticide,
grazing,
Water Pollution,
climate change Chemical fertilizer,
Deforestation,
Plasticulture,
Antibiotics
__________1. This is the cultivation of a single crop in large areas.
Vast tracts of land are converted to rice farms, sugar farms, and
coconut farms.
__________2. Farmers spray these chemicals to kill insect pests and
weeds.
__________3. Monocrops usually require large amounts of
_____________. Continuous and uncontrolled use of chemical
fertilizers may increase soil acidity, thus destroying soil structure.
__________4. It is clearing the Earth's forests on a large scale
worldwide and resulting in many land damages. One of the
causes of deforestation is to clear land for pasture or crops.
__________5. Is the use of plastic mulch in agriculture. Farmers use
plastic sheets as mulch to cover 50-70% of the soil and allow them
to use drip irrigation systems to have better control over soil
nutrients and moisture.
___________6. A huge amount of agricultural territory is used
primarily as pasture for cattle and other livestock.
___________7. Antimicrobial resistant bacteria can move from farms
to humans through food and airborne dust.
___________8. Resulting from conventional agricultural practices is
wide-reaching, affecting both surface and groundwater sources,
in agricultural communities and those located downstream
___________9. Influences social and environmental determinants of
health, including air and water quality and food security.
Agriculture and related activities contribute significantly to climate
change through greenhouse gas (GHG) emissions.
__________10. The gradual increase in the concentration
of phosphorus, nitrogen, and other plant nutrients in an aging
aquatic ecosystem such as a lake.
4
II. WHAT I NEED TO KNOW
DISCUSSION
Humans are the top consumers in many food pyramids. To increase food
production, they use methods that have an effect on food chains and food
webs. Some of the farming practices are described as follows:
Monoculture. This is the
cultivation of a single crop in large
areas. Vast tracts of land are
converted to rice farms, sugar
farms, and coconut farms. By
limiting the cultivation of different
kinds of plants, people also
deprive many animals of their food
and home. These animals, some of
which feed on insect pests, move
to other places. Only the insect
pests that eat the monocrop
remain in the area.
sustainbiodiversity.weebly.com
Herbicides and Insecticides.
Farmers spray their crops with
insecticides
to kill insect pests, and
sciencemag.org
with herbicides to kill weeds. However,
the chemicals also destroy other
organisms, including beneficial insects
and soil organisms which help in
decay.
Insecticides move up the
food pyramid and accumulate in the
body of organisms. The smallest
concentration of the chemical is at
the base of the pyramid occupied by
producers. The amount increases
towards the top. The greatest
concentration is found in the top
consumers such as birds, mammals,
and humans.
5
Chemical Fertilizers.
Continuous
and
uncontrolled
use
of
chemical fertilizers may
increase soil acidity, thus
destroying soil structure.
Findings show that more
fertilizers are needed for the
same amount of yield after
years
of
monoculture.
Fertilizers may run off to
rivers, ponds, and lakes.
Accumulation of fertilizers
may cause the death of
these bodies of water.
Fertilizers in the water will
cause increased growth of
algae and other water
plants.
fertilizer-machinery.com
Deforestation is clearing the
Earth's forests on a large scale
worldwide and resulting in many
land damages. One of the causes
of deforestation is to clear land for
pasture or crops. According to
British
environmentalist Norman
Myers, 5% of deforestation is due
to cattle ranching, 19% due to
over-heavy logging, 22% due to
the
growing
sector
of palm
oil plantations, and 54% due
to slash-and-burn farming.
iunc.org
Plasticulture is
the
use
of plastic
mulch in
agriculture.
Farmers use plastic sheets as mulch
to cover 50-70% of the soil and allow
them to use drip irrigation systems to
have
better
control
over soil
nutrients and moisture. Rain is not
required in this system, and farms
that use plasticulture are built to
encourage the fastest runoff of rain.
The
use
of pesticides with
plasticulture allows pesticides to be
transported easier in the surface
runoff towards wetlands or tidal
creeks.
6
canr.msu.edu
Livestock Grazing - A huge
amount of agricultural territory is used
primarily as pasture for cattle and
other livestock. In the western United
States,
counting
both
federally
managed and privately owned
grazing lands, hundreds of millions of
acres are set aside for this purpose—
more than for any other type of land
use.
Agricultural
livestock
are
responsible for a large proportion of
theguiardians.com
global greenhouse gas emissions, most
notably
methane.
In
addition,
overgrazing is a major problem
Antibiotics Large-scale use
regarding environmental sustainability.
of antibiotics in agriculture (for nontherapeutic purposes) compromises
drug effectiveness in humans.
Antimicrobial resistant bacteria can
move from farms to humans
through food and airborne dust.
These bacteria have also been
found
in
raw
and
treated
drinking water sources, although the
presence
cannot
be
directly
Fo
attributed to agriculture.
foodnavigator.com
Water pollution resulting from
conventional agricultural practices
is wide-reaching, affecting both
surface and groundwater sources, in
agricultural communities and those
located downstream.
. Water
quality standards for agriculturerelated
pollution
levels
include microbial
pathogens, nutrient
pollution,
and pesticides.
blog.ipleaders.in
7
Climate
change influences
social
and
environmental
determinants of health, including air
and water quality and food security.
Agriculture and related activities
contribute significantly to climate
change
through greenhouse
gas (GHG)
emissions.
The
total
accumulated emissions associated
with
agriculture
constitutes
approximately one-third of
GHG
emissions worldwide.
cocoalife.org
onlinesciencenotes.com
Eutrophication,
the
gradual
increase
in
the
concentration
of phosphorus, nitrogen, and other
plant
nutrients
in
an
aging
aquatic ecosystem such as a lake. The
productivity or fertility of such an
ecosystem naturally increases as the
amount of organic material that can
be broken down into nutrients
increases. This material enters the
ecosystem primarily by runoff from
land that carries debris and products
of the reproduction and death of
terrestrial organisms.
Whalecoastconservation.org
8
Top 5 sustainable and eco-friendly farming practices
With the rising awareness about the environmental harm caused by
large-scale agriculture, eco-friendly farming has become a priority. The
solution which can offset damages such as forest clearings, destruction of
habitats, the negative impact of pesticides and intense carbon outputs is
sustainable farming. Both policymakers and environmentalists are actively
promoting eco-friendly and sustainable farming solutions to overcome these
damages. Here are the top 5 sustainable farming practices which guarantee
a green and environmentally friendly growth of vegetables and plants.
1.Permaculture is a food production system which mimics how vegetables
and plants grow in natural ecosystems. It applies natural principles which
combine intention, smart farming and design to reduce waste of resources
and increase production efficiency. The design techniques in permaculture
include growing grains and vegetables without tillage, each plant
undertaking various purposes, herb and plant spirals, hügelkultur beds and
developing swales to hold water.
motherearthnews.com
2. Aquaponics & Hydroponics are innovative farming methods which involve
soilless plant and vegetable growth, feeding the plants with nutrients which
are carried by the water. Hydroponics systems involve using mineral solutions
to feed the plants' roots directly in a passive medium such as perlite or gravel.
However, aquaponics farming
systems
combine
aquaculture
and
hydroponics elements. Water which contains nutrients resulted from the
mineralization of fish waste feeds the roots of plants and vegetables which
can grow in various mediums. The water is purified by the plants and returns
to the hydroponics section of the system.
9
Freshwater.com
3. Using Renewable Energy Resources Sustainable farming involves the use of
alternative energy sources such as hydropower, solar power or wind farms
which are eco-friendly. Solar panels can be used to run pumping and heating
systems. Also, hydroelectric power sourced from river water can be used for
various farming machinery. Farmers can compare energy consumption rates
by using an online energy compare site to identify the best suitable power
sources.
countrysideonline.co.uk
10
4. Crop Rotation & Polycultures Farmers can decrease the chances of plant
and vegetable diseases through crop diversification on a surface of land and
through crop rotation techniques. The practices can also reduce the amount
of pesticides and chemical fertilizers required
alamy.com
5. Trees Can Increase Crop Yields Agroforestry is a farming method which
involves growing shrubs and trees among other plants and vegetables. It
combines forestry and agricultural practices to guarantee a sustainable and
highly productive approach to land use. The system mimics forest ecosystems
found in nature and it's designed to comprise multiple layers of food forests. It
includes perennial plants such as fruit trees, perennial herbs, mushrooms, and
other vegetables on the ground level and underground root vegetables.
Compared to traditional farming systems, agroforestry can double crop yields
and significantly decreases the need for chemical fertilizers or pesticide. Just
like below, agroforestry in rice production.
fao.org
11
III. WHAT HAVE I LEARNED
POST-TEST
Multiple choice: Choose the letter of the best answer. Write your answers in
your notebook/paper.
1. This is the cultivation of a single crop in large areas. Vast tracts of land are
converted to rice farms, sugar farms, and coconut farms.
a. Water pollution b. Monoculture c. insecticide d. antibiotics
2. Farmers spray these chemicals to kill insect pests and weeds.
a. Water pollution b. Monoculture c. insecticide d. antibiotics
3. Continuous and uncontrolled use of ______________ may increase soil acidity,
thus destroying soil structure.
a. Water pollution b. Chemical fertilizer c. insecticide d. antibiotics
4. It is clearing the Earth's forests on a large scale worldwide and resulting in many
land damages. One of the causes of deforestation is to clear land for pasture or
crops.
a. Deforestation b. Chemical fertilizer c. insecticide d. antibiotics
5. Is the use of plastic mulch in agriculture. Farmers use plastic sheets as mulch to
cover 50-70% of the soil and allow them to use drip irrigation systems to have
better control over soil nutrients and moisture.
a. Deforestation
b. chemical fertilizer c. plasticulture d. Antibiotics
6. A huge amount of agricultural territory is used primarily as pasture for cattle and
other livestock.
a. Grazing
b. deforestation c. pesticide d. antibiotics
7. Antimicrobial resistant bacteria can move from farms to humans
through food and airborne dust.
a. Grazing
b. deforestation c. pesticide d. antibiotics
8. Resulting from conventional agricultural practices is wide-reaching, affecting
both surface and groundwater sources, in agricultural communities and those
located downstream.
a. Water pollution b. Monoculture c. insecticide d. antibiotics
9. Influences social and environmental determinants of health, including air and
water quality and food security. Agriculture and related activities contribute
significantly to climate change through greenhouse gas (GHG) emissions.
a. Water pollution b. Monoculture c. climate change d. antibiotics
10. The gradual increase in the concentration of phosphorus, nitrogen, and other
plant nutrients in an aging aquatic ecosystem such as a lake.
a. Water pollution
b.
Monoculture
c. climate change
d.
eutrophication
11. Farmers can decrease the chances of plant and vegetable diseases through
crop diversification on a surface of land and through crop rotation techniques.
a. crop rotation
b. agroforestry
c. using renewable energy resources
d. hydrophonics
12
12.
Sustainable farming involves the use of alternative energy sources such as
hydropower, solar power or wind farms which are eco-friendly.
a. crop rotation
b. agroforestry
c. using renewable energy resources
d. hydrophonics
13. A farming method which involves growing shrubs and trees among other plants
and vegetables.
a. crop rotation
b. agroforestry
c. using renewable energy resources
d. hydrophonics
14. Is a food production system which mimics how vegetables and plants grow in
natural ecosystems.
a. permaculture
b. agroforestry
c. hydroponics
d. crop rotation
15. Are innovative farming methods which involve soilless plant and vegetable
growth, feeding the plants with nutrients which are carried by the water.
a. permaculture
b. agroforestry
c. hydroponics
d. crop rotation
13
REFERENCES:
Books:
Department of Education (2013) Science - Grade 8 Learner’s Module First
Edition, 2nd Floor Dorm G, Philsports Complex Meralco Avenue, Pasig
City, Philippines. 1600
Vibal Publishing House (2003) Science and Technology Series, Functional
Biology, Modular Approach. Vibal Publishing House, 1253, G. Araneta
Ave., Quezon City
Websites
alamy.com
blog.ipleaders.in
canr.msu.edu
cocoalife.org
countrysideonline.co.uk
dreamstime.com
fao.com
fertilizer-machinery.com
foodnavigator.com
Freshwater.com
hortidaily.com
iunc.org
motherearthnews.com
14
DEPARTMENT OF EDUCATION
SCHOOLS DIVISION OF NEGROS ORIENTAL
SENEN PRISCILLO P. PAULIN, CESO V
Schools Division Superintendent
FAY C. LUAREZ, TM, Ed.D., Ph.D.
OIC - Assistant Schools Division Superintendent
Acting CID Chief
NILITA L. RAGAY, Ed.D.
OIC - Assistant Schools Division Superintendent
ROSELA R. ABIERA
Education Program Supervisor – (LRMS)
ARNOLD R. JUNGCO
PSDS - Division Science Coordinator
MARICEL S. RASID
Librarian II (LRMDS)
ELMAR L. CABRERA
PDO II (LRMDS)
JUSTIN PAUL ARSENIO C. KINAMOT
Writer
KEENJI L. ARMENTANO
Layout Artist
_________________________________
ALPHA QA TEAM
MA. ALETTA AARONA R. GAJELOMO
JUSTIN PAUL ARSENIO C. KINAMOT
MIEL C. PACULANANG
PETER PAUL A. PATRON
LYN-NO A. REGALADO
BETA QA TEAM
LIEZEL A. AGOR
JOAN Y. BUBULI
LIELIN A. DE LA CERNA
PETER PAUL A. PATRON
THOMAS JOGIE U. TOLEDO
DISCLAIMER
The information, activities and assessments used in this material are designed to provide
accessible learning modality to the teachers and learners of the Division of Negros Oriental. The contents
of this module are carefully researched, chosen, and evaluated to comply with the set learning
competencies. The writers and evaluator were clearly instructed to give credits to information and
illustrations used to substantiate this material. All content is subject to copyright and may not be
reproduced in any form without expressed written consent from the division.
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SYNOPSIS
ANSWER KEY
This student learning kit
deals the categories of the
one-way flow of energy and
the cycling of materials in an
ecosystem. This learning kit
identifies the different human
activities that affects the
ecosystem. This kit enumerates
the
suggested
ways
to
minimize human impact on the
environment. Propose a plan
on how to help in conserving
and
protecting
the
environment.
This lesson is in line with
the latest Most Essential
Learning
Competency
prepared by our department
for this pandemic.
AUTHOR
Author: JUSTIN PAUL ARSENIO C.KINAMOT, MAEd Gen. Sci. A
graduate of Bachelor in Secondary Education major in General
Science from St. Paul University Dumaguete in 2004. He has finished
his Graduate Studies from Foundation University with the degree
Master of Arts in Education Major in General Science in 2014 and has
recently Completed his Academic Requirement of Doctor of Education
major in Science Education at Negros Oriental State University.. A
consistent writer for Unified Lesson Plans and Modules in Science for
the Department of Education, Division of Negros Oriental and the
current focal person for Biology Subject. A teacher III, presently
connected at Crisostomo O. Retes National High School having an
advisory in Grade 8.
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