How does agriculture affect the hydrological cycle

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Research suggests that these changes have increased the risk of catastrophic ecosystem regime shifts. We identify and review evidence for agriculture-related regime shifts in three parts of the hydrological cycle: interactions between agriculture and aquatic systems, agriculture and soil, and agriculture and the atmosphere.

Improperly managed agricultural activities may impact surface water by contributing nutrients, pesticides, sediment, and bacteria, or by altering stream flow. Fertilizer and pesticide use, tillage, irrigation, and tile drainage can affect water quality and hydrology.

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Can agricultural changes across the hydrological cycle cause regime shifts?

The hydrological cycle can be seen as the ‘bloodstream of the biosphere’ [18], because runoff, groundwater and evapotranspiration move materials among different ecosystems and alter energy balances in landscapes. This paper examines how agricultural changes across the whole hydrological cycle can produce regime shifts.

How does agriculture affect the water cycle Quizlet?

How does agriculture affect the water cycle? Conventional agricultural techniques use a lot of water during summer time. One portion evaporates easily (there is no need for evaporation when you try to irrigate your goods). If you are using surface water bodies to irrigate your goods, you can dry up water in lakes, rivers, impoundments.

What is the hydrological cycle?

The hydrological cycle is also commonly known as the water cycle. It describes the material flow of water throughout the Earth. It comprises a series of steps that explain how water moves across the Earth and changes various forms. These steps result in continuous circulation of water between oceans, the atmosphere, and the land.

What are the problems associated with agriculture?

If you are using surface water bodies to irrigate your goods, you can dry up water in lakes, rivers, impoundments. If you are using groundwater resources, you can deplete groundwater level even finish all extractable water of your aquifer. These are the problems associated with agriculture.

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How does agriculture affect the water?

Excessive irrigation can affect water quality by causing erosion, transporting nutrients, pesticides, and heavy metals, or decreasing the amount of water that flows naturally in streams and rivers.


How does human activities affect the hydrological cycle?

Human activities can influence the hydrologic cycle in many other ways. The volumes and timing of river flows can be greatly affected by channeling to decrease the impediments to flow, and by changing the character of the watershed by paving, compacting soils, and altering the nature of the vegetation.


What are the factors affecting hydrological cycle?

Factors Affecting The Hydrological Cycle Flashcards PreviewRelief. Where precipitation falls. … Climate. How water is stored. … Geology. Permeable rocks allow for groundwater storage, percolation, base flow, through flow and infiltration. … Vegetation. … Irrigation. … Mining. … Urbanisation. … Dam building and reservoirs.More items…


How does agriculture affect water here on Earth?

Agricultural contaminants can impair the quality of surface water and groundwater. Fertilizers and pesticides don’t remain stationary on the landscape where they are applied; runoff and infiltration transport these contaminants into local streams, rives, and groundwater.


Why would farmers care about the hydrologic cycle?

The hydrologic cycle is important because it is how water reaches plants, animals and us! Besides providing people, animals and plants with water, it also moves things like nutrients, pathogens and sediment in and out of aquatic ecosystems.


How does deforestation affect hydrological cycle?

Deforestation can disrupt the water cycle by decreasing precipitation which can lead to changes in river flow and water volume. Research has shown that the Amazon needs 80% of the trees standing to continue this critical hydrological cycle.


How does vegetation affect hydrological cycle?

Vegetation plays an important role in the water cycle by preventing soil erosion and increasing groundwater levels. In areas with thick vegetation cover, the foliage cover breaks the force of precipitation falling on the ground, which may otherwise cause erosion.


What are the common agricultural practices that disrupt the hydrologic cycle?

Fertilizer and pesticide use, tillage, irrigation, and tile drainage can affect water quality and hydrology.


How does agriculture affect the water cycle for kids?

Conventional agricultural techniques use a lot of water during summer time. One portion evaporates easily (there is no need for evaporation when you try to irrigate your goods). If you are using surface water bodies to irrigate your goods, you can dry up water in lakes, rivers, impoundments.


How is agriculture bad for rivers?

In addition, agriculture remains a major source of water pollution; agricultural fertiliser run-off, pesticide use and livestock effluents all contribute to the pollution of waterways and groundwater.


Humans have modified the water cycle through agriculture

Human transformation of global water flows has dramatically impacted ecosystems and the services they generate. Through water withdrawals, land use and land cover changes, agriculture, which covers almost 40% of the terrestrial surface [1], is arguably the major way in which humans change water quantity and quality ( Box 1 ).


Three parts of the hydrological cycle where agriculture can trigger regime shifts

The hydrological cycle can be seen as the ‘bloodstream of the biosphere’ [18], because runoff, groundwater and evapotranspiration move materials among different ecosystems and alter energy balances in landscapes. This paper examines how agricultural changes across the whole hydrological cycle can produce regime shifts.


There is large variation in the spatial scales and reversibility of regime shifts

The regime shifts we have identified as related to agricultural changes to water flows ( Table 1) operate at a wide range of spatial scales and are reversible at different temporal scales ( Figure 2 ). Agriculture–aquatic system regime shifts occur at the watershed to river basin scales but vary from years to millennia in their reversibility.


Agriculture interacts with other drives to produce water-related regime shifts

Regime shifts are triggered by the interaction of changes internally in a system and changes in external drivers ( Box 2 ). In Table 1, we identify critical internal ‘slow variables’ that strongly influence the vulnerability of an ecosystem to regime shifts.


Enhancing resilience of agricultural landscapes

Hydrological alterations due to growing agricultural demands ( Box 1) are likely to increase the risk of surprising regime shifts unless management practices are changed.


Conclusions and research challenges

There is strong evidence that agricultural modification of water flows can produce a variety of ecological regime shifts that operate across a range of spatial and temporal scales. In a world of growing demands for water, agricultural products and other ecosystem services, there will inevitably be ecological surprises.


Acknowledgements

L.J.G.’s research was funded by the Swedish Research Council for the Environment, Agricultural Sciences and Spatial Planning (Formas), and G.D.P.’s work was funded by the Canada Research Chairs Program.


irrigation

abstraction of river-water will reduce downstream flow. if water is removed from an aquifer faster than it is replaced then the water table will be lowered. this can cause surface water features such as springs, rivers and marshland to dry up.


Run off and drainage

reduced vegetation cover and soil compaction from machinery use can reduce the amount of water that drains into the soil and therefore increase run off. this can increase soil erosion and the need for irrigation.


How does farming affect the water cycle?

evapotranspiration from the crops may be reduced if the previous habitat was forest, or it may be increased if an arid area was cultivated and irrigated. this may change the rainfall in areas downwind of the farmland.


Methods of evaluation

Different approaches can be used to estimate the effect on water resources of global warming of which the main ones are:


General circulation models

A GCM model typically has four components: atmospheric, land, ocean and sea ice. As the four models are interactive, production runs must include all four model components. Initially, the atmospheric model was developed to a relatively high level of sophistication, whilst the land phase and the ocean components were very simplistic.


Recent changes in global runoff

Lake Chad is situated on the border of the Sahara between latitudes 12°N and 14°30’N and longitudes 13°E and 15°30’E. The lake has no outlet to the sea and is the main focus of an internal drainage basin of 2 500 000 km 2 that collects water from Algeria, Chad, Niger, Nigeria, Cameroon, Sudan and the Central African Republic.


Conclusions

1. The effect of climate change on available water resources in most regions, while significant, will be small compared with demands generated by population growth, industrialization, urbanization, land-use changes and improved standards of living. In many countries resources are already fully committed and water will become a scarce commodity.


Why are hydrological variables suspect?

This is because their large variability in time and space and because their ground observation network is sparse (extremely so in the case of evaporation).


Can droughts coexist?

Future droughts and “natural” climate variability. One implication of the existence of two types of drought is that the two can coexist, sometimes adding and at other times offsetting one another.

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