<p>With the completion of a 3，046-kilometer green belt on the edge of the Taklamakan Desert， China's "locking-edge and fixing-sand" strategy can be said to have achieved a decisive victory. However， some people might argue， "Deserts are also beneficial to the ecosystem! Aren't you harming nature by destroying them?"</p>
Well， that’s an interesting point. Let’s get straight to the point. Deserts do have their uses， but for China and the world， we are far from being in a position where we can “afford to have too few deserts.” Today， let’s discuss the actual roles deserts play in the natural environment.
The Functions of Deserts: Regulating Global Climate Through Extreme Temperature Differences
From a global ecosystem perspective， deserts are among Earth’s crucial natural regulators. Deserts experience significant diurnal temperature variations， absorbing heat during the day and releasing it at night. This continuous injection of heat into the atmosphere drives global air circulation， pressure distribution， and other climatic system operations.
This characteristic allows deserts to act as “buffers” in the Earth’s heat cycle. For instance， the Sahara Desert in Africa is characterized by persistent low-pressure troughs and subtropical high-pressure systems overhead. These systems influence the West African monsoon， consequently affecting storm tracks in Europe and the Atlantic.
Nutrient Provider for Rainforests
Simultaneously， deserts sustain intercontinental nutrient cycles that span mountains， oceans， and even continents. The Amazon rainforest， occupying half of the world’s tropical rainforest area， truly lives up to its “lungs of the Earth” moniker.
However， the soil in the Amazon is actually extremely poor. This is primarily due to the Amazon River.
As the world’s largest river by discharge， the Amazon River’s water flow is equivalent to 88 times that of the Yellow River. While this provides abundant water， it also leads to severe soil erosion. More critically， the eroded soil contains approximately 22，000 tons of phosphorus.
Phosphorus is an essential nutrient for plant growth and is vital for the tens of thousands of plants in the rainforest. However， with soil erosion， a significant amount of phosphorus is carried into the ocean.
Without external phosphorus input， the Amazon rainforest would have long been barren given this rate of loss. Fortunately， nature seems to have orchestrated a balancing mechanism.
That mechanism is the Sahara Desert. As the world’s largest desert， the Sahara has a dry climate and is covered with vast expanses of sand.
This might seem unrelated to the lush Amazon rainforest. However， the Sahara Desert generates a large amount of dust annually， and this dust is rich in minerals like iron and phosphorus， which are essential for plant growth.
Under the influence of the northeast trade winds， massive amounts of dust traverse thousands of kilometers across the vast Atlantic Ocean each year， eventually settling in the Amazon rainforest.
According to NASA data， the dust blown from the Sahara annually reaches 182 million tons， equivalent to the transport capacity of 700，000 large trucks. Of this， approximately 27.7 million tons reach the Amazon. This dust contains nearly 22，000 tons of phosphorus， which precisely replenishes the phosphorus lost through erosion in the Amazon.
In this regard， the Sahara Desert acts as a “blood supply heart” for the Amazon rainforest， collectively completing a grand continental natural cycle.
The dust that falls into the ocean along the way also carries rich elements like iron and phosphorus， which nourish marine plankton. It can be said that the existence of deserts is indeed an indispensable part of the entire ecosystem.
Home to Extreme Ecosystems
In terms of biodiversity， deserts also possess unique vitality. The harsh environment has fostered plants with drought resistance， water storage， and soil fixation capabilities. Animals， too， must have adaptations for water conservation， salt tolerance， and heat avoidance to survive here.
Iconic examples include cacti， poplar trees， and camels. Deserts harbor a complete and unique ecological structure.
Healthy vs. Unhealthy Deserts
However， only about 10% of the world’s deserts are considered “healthy.” These deserts were naturally formed through long-term geological evolution and climate change， with ecosystems that have reached a relatively stable equilibrium. Examples include the core areas of the Sahara Desert and the hinterlands of China’s Taklamakan Desert. They are integral components of the Earth’s terrestrial ecosystem， sustaining specific biodiversity and climate regulation functions.
The remaining 90% of deserts are largely areas of degraded land caused by human activities. For instance， before its management， China’s Kubuqi Desert was contributing 160 million tons of sand to the Yellow River annually， leading to significant soil erosion.
This sediment not only exacerbated siltation in the lower reaches of the Yellow River， raising the riverbed and increasing flood risks but also continuously diminished local soil fertility， leading to reduced crop yields and a desperate situation of “desert encroaching and people retreating.”
The relentless expansion of deserts， swallowing fertile land， is desertification.
China’s Desertification Control: Eliminating Desertification， Not Deserts
Therefore， what we have been doing all along is not simply “eliminating deserts，” but rather “eliminating desertification.”
“Desertification” is the process by which grasslands and forest lands gradually degrade into sandy land due to human activities disrupting ecological balance. It is essentially a “human-induced ecological wound.” Consequently， the core of desertification control is not to fight against nature but to repair the damaged ecosystem and prevent the uncontrolled expansion of desert boundaries.
Unique Desertification Control Technologies and China’s Desertification Challenges
In 1977， a significant event occurred at a United Nations conference on desertification: Beijing was listed as a “city on the edge of the desert.” At that time， the Mu Us Desert was 800 kilometers away from Beijing， the Kubuqi Desert was 700 kilometers away， and the Hunshandake Sandy Land was a mere 200 kilometers away.
The national forest coverage rate was only 12%， with one-third of the country facing threats of drought and desertification. Dust storms were a frequent occurrence.
How Did Desertification Control Projects Solve the Problem?
In 1978， the “Three-North Shelterbelt Program” (Sannbei Program) was officially launched. This is a large-scale artificial forestry ecological project in China aimed at addressing the ecological fragility of the Northwest， North， and Northeast regions.
It spans 4，480 kilometers from east to west and up to 1，460 kilometers from north to south， covering 13 provinces with a total area of 4.069 million square kilometers， accounting for 42.4% of China’s land area.
The planned duration is from 1978 to 2050， representing a relay race across three to four generations. This monumental， “wonder-level” super project was initiated to curb the expansion of desertification and improve climate and soil and water conservation.
The recently completed “locking-edge” project on the periphery of the Taklamakan Desert is one of the flagship campaigns of the Three-North Program.
The Taklamakan is the world’s second-largest shifting sand desert， where the wind can move entire sand dunes， shifting like waves.
Under traditional approaches， planting trees would be the solution to block sandstorms. However， due to the shifting sand dunes and extremely scarce water resources， tree planting is not feasible， creating a vicious cycle!
This is where straw checkerboards， a “divine artifact” against drifting sand， come into play. It might seem peculiar: with entire sand dunes moving in the wind， what good can planting a bit of straw in the sand do?
Remarkably， it is indeed effective!
Desertification control workers use reeds， straw， or other locally suitable plant materials， embedding them 15-20 cm deep into the sand surface to form a dense “straw checkerboard” grid structure.
Initially， wind blows directly across the ground， picking up sand. With straw checkerboards， these grids act like miniature fortresses， effectively reducing wind speed. The wind force at the surface is blocked by the checkerboards， creating vortexes within the squares.
This prevents the sand from being blown away. Over time， the sand within the checkerboards naturally forms a bowl-shaped depression， higher around the edges and lower in the center. This facilitates sand deposition， retains rainfall， and slows evaporation. As the straw decomposes， it naturally enriches the soil with nutrients and increases its water-holding capacity.
The size of each straw checkerboard is also crucial; if too large， the central depression can be eroded by wind into a deep pit， hindering plant root establishment. If too small， it cannot form this sand-trapping structure and may be easily destroyed by wind despite appearing dense. Therefore， they are typically 1m x 1m in size.
Simultaneously， drought-resistant plants like *Caragana korshinskii*， *Hedysarum scoparium*， or other suitable species can be sown within the checkerboards. The plant roots further stabilize the sand dunes. Through these small straw checkerboards， China achieves an annual net sand fixation of 1，980 square kilometers. If we were to build a 100-square-meter small house on this area， it could accommodate 19.8 million houses!
Of course， afforestation is also an effective method. For example， in areas like Zhanggutai in Liaoning and Tongyu in Jilin， where annual precipitation can reach over 500 millimeters， making them semi-arid to semi-humid transition zones， far exceeding the dry desert conditions we typically associate with deserts.
However， due to thousands of years of human activity， the original grasslands and forests here have severely degraded. Once the protective layer of vegetation is lost， the land becomes susceptible to rainwater erosion， and the exposed surface is further eroded by strong winds， leading to desertification. Despite sufficient rainfall， the soil lacks water retention capacity， and each rain event causes more soil and water loss.
In such areas， desertification controllers have opted for mixed forests of *Pinus sylvestris var. mongolica* and poplar trees as the core of their treatment. The deep root system of *Pinus sylvestris var. mongolica* can penetrate the sandy layer to absorb groundwater， playing a role in sand fixation and soil improvement. Poplar trees grow rapidly， quickly forming a canopy layer that acts as a windbreak.
The Three-North Shelterbelt Program covers an immense area. The desertification control methods vary across different regions based on local climate and soil conditions; a one-size-fits-all approach is not applicable. Tailoring strategies to local circumstances is paramount.
With the advancement of the times， technologies such as remote sensing， precision irrigation， and forest ecosystem monitoring are increasingly being utilized.
Today， desertification control has entered a virtuous cycle.
For instance， the “planting licorice under photovoltaic panels” model in the Kubuqi Desert demonstrates this. Densely arranged photovoltaic panels not only efficiently absorb solar energy for electricity generation but also create shaded strips.
Technicians leverage this microenvironment to plant plants like licorice beneath the panels. These plants have developed root systems that firmly anchor the sandy soil and possess economic value. The vegetation helps reduce temperatures， lowering the operating temperature of the photovoltaic panels and thus improving their efficiency. Furthermore， the cultivation of licorice enhances sand fixation， achieving a synergistic effect where 1 + 1 > 2.
Additionally， you may have heard of “farming seafood in the desert.” While it sounds far-fetched， it is indeed possible.
The saline-alkali lake water in the Taklamakan Desert， unlivable for most plants and animals， can be treated to simulate a marine environment for cultivating various seafood. Fish feces are converted by microorganisms into amino acids， calcium， magnesium， potassium， and other nutrients， which are then absorbed by algae and become food for shellfish. The shellfish， in turn， purify the water， forming an ecological cycle.
Combined with the desert’s long daylight hours and significant diurnal temperature variations， the luster and quality of pearls produced can even rival those from many traditional pearl farming regions.
Xinjiang also utilizes meltwater from the Tianshan Mountains and spring water to farm salmon， achieving an annual output of 200-300 tons in 2024. While these farming projects might not be directly part of the Three-North Program， they complement each other.
Historically， desertification control was viewed as an endeavor with only costs and no immediate returns， with benefits only observable in terms of broader ecology or long-term development. However， with these new approaches， desertification control itself is now generating tangible and substantial rewards. This signifies a shift from “campaign-style” governance to sustainable development.
Achievements in Desertification Control
According to UN data， over the past decade， China has contributed a quarter of the world’s newly greened land， with desertification control accounting for over 30% of this contribution.
Over 47 years， the forest coverage rate in the Three-North regions has increased from 5.05% to 13.57%， with a cumulative afforested and preserved area of 30.14 million hectares， equivalent to 4.5 times the size of Taiwan Island.
Furthermore， it has driven economic development. For instance， in Xinjiang， the planting area for cash crops like red dates and walnuts around the shelterbelts has reached 6 million mu， with an annual output value exceeding 20 billion yuan. In Ningxia， economic forests such as goji berries and apples have helped boost the income of 300，000 households， with an average annual per capita income increase of over 5，000 yuan. In addition to ecological restoration， these initiatives have created over a million job opportunities.
In summary:
While deserts possess ecological value， when they expand uncontrollably， active intervention is the responsible approach to environmental protection. On the journey to transform yellow sand into green oases， we have gained far more than just vegetation recovery. From micro-scale biological sand fixation to the construction of grand ecological barriers; from meticulous water resource management to developing photovoltaic industries tailored to local conditions， it truly demonstrates that ecological protection and economic development can go hand in hand.
So， why are we so persistent in controlling deserts? Not because it is easy， but because it is necessary. And perhaps， this is the best answer to the question， “What is the use of deserts?”
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