Tugas Softskill 'Active-Passive Voice'

Environmental Impact of Fishing and Irrigation

Fishing

The environmental impact of fishing can be divided into issues that involve the availability of fish to be caught. Such as overfishing, sustainable fisheries, and fisheries management; and issues that involve the impact of fishing on other elements of the environment, such as by-catch.

These conservation issues are part of marine conservation. These conservations are addressed in fisheries science programs. There is a growing gap between how many fish are available to be caught and humanity’s desire to catch them. A problem that gets worse as the world population grows.

Similar to other environmental issues, there can be conflict between the fishermen who depend on fishing for their livelihoods and fishery scientists who realize that if future fish populations are to be sustainable then some fisheries must reduce or even close.

The journal Science published a four-year study in November 2006, which predicted that, at prevailing trends, the world would run out of wild-caught seafood in 2048. The scientists stated that the decline was a result of overfishing, pollution and other environmental factors that were reducing the population of fisheries at the same time as their ecosystems were being degraded. Yet again the analysis has met criticism as being fundamentally flawed, and many fishery management officials, industry representatives and scientists challenge the findings, although the debate continues. Many countries, such as Tonga, the United States, Australia and New Zealand, and international management bodies have taken steps to appropriately manage marine resources.

Irrigation

The environmental impact of irrigation includes the changes in quantity and quality of soil and water as a result of irrigation and the ensuing effects on natural and social conditions at the tail-end and downstream of the irrigation scheme.

The impacts stem from the changed hydrological conditions owing to the installation and operation of the scheme.

An irrigation scheme often draws water from the river and distributes it over the irrigated area. As a hydrological result it is found that:

• The downstream river discharge is reduced.
• The evaporation in the scheme is increased.
• The groundwater recharge in the scheme is increased.
• The level of the water table rises.
• The drainage flow is increased.

These may be called direct effects.
The effects thereof on soil and water quality are indirect and complex. Water logging and soil salination are part of these, whereas the subsequent impacts on natural, ecological and socio-economic conditions is very intricate.

Irrigation can also be done extracting groundwater by (tube) wells. As a hydrological result it is found that the level of the water descends. The effects may be water mining, land/soil subsidence, and, along the coast, saltwater intrusion.

Irrigation projects can have large benefits, but the negative side effects are often overlooked. Agricultural irrigation technologies such as high powered water pumps, dams, and pipelines are responsible for the large-scale depletion of fresh water resources such as aquifers, lakes, and rivers. Humans appropriate more than 50% of the planet’s fresh water, mostly for use in irrigation. As a result of this massive diversion of freshwater, lakes, rivers, and creeks are running dry, severely altering or stressing surrounding ecosystems, and contributing to the extinction of many aquatic species. 

(http://en.wikipedia.org/wiki/Human_impact_on_the_environment) 

Active Sentences
1.      These conservation issues are part of marine conservation. (This is an active sentence because the sentence is not contained be + past participle.)
2.      The journal Science published a four-year study in November 2006, which predicted that, at prevailing trends, the world would run out of wild-caught seafood in 2048. (This sentence contains a few past participles but this sentence is active sentence because this is a past tense.)
3.      The effects thereof on soil and water quality are indirect and complex. (This is an active sentence because the sentence is not contained be + past participle.)
4.      Many countries, such as Tonga, the United States, Australia and New Zealand, and international management bodies have taken steps to appropriately manage marine resources. (This is an active sentence because the sentence is contained have + taken {present perfect}.)
5.      Humans appropriate more than 50% of the planet’s fresh water, mostly for use in irrigation. (This is an active sentence because the sentence is not contained be + past participle.)
 
Passive Sentences
1.      The environmental impact of fishing can be divided into issues that involve the availability of fish to be caught. (This is a passive sentence because the sentence contains be and past participles {divided and caught}.)
2.      These conservations are addressed in fisheries science programs. (This is a passive sentence because the sentence contains be and past participles {are + addressed}.) 
 
3. The groundwater recharge in the scheme is increased.
(This is a passive sentence because the sentence contains be and past participles {is + increased}.)
4.      These may be called direct effects. (This is a passive sentence because the sentence contains be and past participles {be + called}.)
5.      Irrigation can also be done extracting groundwater by (tube) wells. (This is a passive sentence because the sentence contains be and past participles {be + done}.)