Steppes
Steppes are temperate grassland plains characterized by a semi-arid climate, experiencing distinct seasonal changes, with hot summers and cold winters. These ecosystems receive between ten and twenty inches of rainfall annually, which supports the growth of short grasses but is insufficient for taller vegetation or trees. Despite harsh conditions, steppes are home to various plant and animal species, including grazing animals like horses and cattle, as well as smaller animals such as marmots. The Eurasian steppe is the largest and historically significant, serving as a key trade route along the Silk Road and a vital area for equestrian cultures, especially during the time of Genghis Khan. Other notable steppes include the short-grass prairie in North America, which is crucial for livestock farming. However, human activities such as overgrazing and intensive agriculture can lead to soil degradation, threatening the ecological balance of these regions. Additionally, steppes are facing challenges from climate change, including biodiversity loss and increased drought conditions, highlighting the need for sustainable management practices to preserve these unique ecosystems.
Subject Terms
Steppes
Steppes are mostly dry grassland plains located in temperate climate zones. Steppes experience four seasons, but the weather swings greatly from intensely hot summers to excessively cold winters. No matter the temperature, steppes are always semi-arid, with enough annual rainfall to support the growth of abundant short grasses but generally insufficient precipitation for taller grasses and never enough for trees. Despite these seemingly extreme conditions, steppes worldwide still provide homes to some animal and plant species.
The Steppe Environment
To qualify as a steppe, a grassland or prairie must be located in a temperate zone, or a climate region between the Earth's poles and the warm, humid tropics. This geographical placement ensures that steppes undergo four seasonal changes a year, though summers can be extremely hot and winters bitterly cold. Steppes receive between ten and twenty inches of rain annually and are therefore referred to as semi-arid. In winter, the coldest areas of a steppe experience their precipitation in the form of heavy snowfalls.
The rainfall that steppes receive is just enough to allow short grasses to grow across almost the entire plain. However, few taller grasses or other vegetation, such as trees, can survive there. For this reason, with mostly short grass and no obstructions on the horizon, steppes generally provide high visibility in all directions.
Despite steppes' lack of abundant vegetation, these grasslands sustain certain kinds of life in their own ways. Small lark, pipit, and bunting birds all live primarily on European steppes, feeding on what insects they can find and nesting in the safety of thick grasses at night. The plentiful grasses of the steppes also provide an endless source of food to a few wild grazing animals, including horses, cattle, sheep, goats, and, on some steppes, camels. Smaller animals, such as marmots, eat the vegetation and dig burrows underground for homes.
Such animals can survive in these often harsh environments because the leaves of steppe grasses grow from the plant base rather than from any branch. This means that even after animals eat away the leaves, the grass can perpetually replenish itself from its base. For this reason, grassy steppes are also fairly resistant to wildfires.
Human Activity on Steppes
Steppes are located on nearly every continent on Earth. The largest and most well known of these is the Eurasian steppe, or simply the Steppe. This stretches from Hungary in Eastern Europe to China in the Far East, with a large portion located in Mongolia. This plain served as the most vital commercial route between Europe and Asia for thousands of years. Merchants from both continents traveled the famous Silk Road across the Eurasian steppe to trade with one another, sharing the open prairie with large herds of wild donkeys, horses, and camels. This steppe continued to play a significant role in world history in the 1200s, when Mongolian warlord Genghis Khan conquered it almost in its entirety, from China, west across Central Asia, and up to the Western Asian border at the Caspian Sea. Genghis Khan relied heavily on tamed horses for transportation and battle, participating in a long-established steppe tradition of equestrianism. Horse riding was a primary part of life for most inhabitants of the Eurasian steppe, both before and after the time of Genghis Khan. It provided efficient transport while serving as the focus of many games and contests held among steppe communities. These cultures and traditions continue to survive, flourishing, for example, on the Eastern Steppe of Mongolia, the world's most extensive stretch of grassland prairie. Here, nomadic tribes shepherd domestic livestock among the few other animals of this steppe, such as gray wolves, Daurian hedgehogs, and saker falcons.
Another of the world's large steppes is the North American short-grass prairie, a subsection of the Great Plains. This extends from western Texas north to the Canadian province of Saskatchewan. The prairie sits entirely in the rain shadow of the Rocky Mountains to the west. This means that the moisture from air blowing east across the continent is blocked by the mountains, preventing much precipitation from falling on the steppe. The rain shadow effect keeps the grass on this prairie short.
As with most other temperate steppes worldwide, the North American steppe is a fertile feeding ground for farmers' livestock. However, too much human activity can deplete a steppe's natural resources before it can replenish itself. Too many animals in an area can lead to overgrazing, while repeatedly plowing soil for agriculture uproots and destroys the rich natural minerals needed to support healthy crops.
Because steppes receive so little annual rainfall, overgrazing and excessive cultivation that degrades the quality of the ground can eventually make grasslands look like deserts. Steppes can never become true deserts because of the precipitation they do receive, but their nutrient-poor soil will prevent new grasses from growing and deny food and shelter to the animals native to this environment. Given the opportunity to exist mostly unspoiled, however, steppes can rejuvenate themselves and survive indefinitely, as they have for thousands of years.
In the twenty-first century, the effects of global climate change could be seen on steppes worldwide. The Eurasian Steppe has experienced decreases in biodiversity directly related to climate change. Pollution, increased drought conditions, more frequent and intense wildfires, soil erosion, changes in vegetation, and the decline of permafrost are all changes to steppes that result from global climate change. Addressing these issues through research, scientific study, and land management is crucial to formulating adaptive management strategies for steppe ecosystems worldwide.
Bibliography
"Eastern Steppe." Wildlife Conservation Society, mongolia.wcs.org/Wild-Places/Eastern-Steppe.aspx. Accessed 7 Oct. 2024.
Robinson, Sarah. "Review of Eurasian Steppes. Ecological Problems and Livelihoods in a Changing World, Edited by Marinus JA Werger and Marja A Van Staalduinen (Springer Series: Plant and Vegetation No. 6)." Pastoralism: Research, Policy and Practice, vol. 3, no. 1, 2013, pp. 1-4, doi.org/10.1186/2041-7136-3-2. Accessed 7 Oct. 2024.
"Steppe." National Geographic Society, 19 Oct. 2023, education.nationalgeographic.org/resource/steppe. Accessed 7 Oct. 2204.
"Steppe (Grassland)." University of Puget Sound, www.pugetsound.edu/academics/academic-resources/slater-museum/biodiversity-resources/world-biomes/characteristics-of-bioclimatic/steppe-grassland. Accessed 7 Oct. 2024.