Is 'Green' the right way to combat desertification and control erosion? Shelterbelt in Northern China was originally planted to function as an ecological barrier against the Northeastern wind and sand storm. In 2009, large extent of Populus deltoides die-off within one year. In the competition entry of WLA 2017, my study investigates the reasons for their die-off and eventually leads to a heated debate to the conservative approach of plantation forest. Whether plantation ('Greening') is the right way to control erosion and climate change. 

The debate comprises 4 dialogues:-

Dialogue 1 - Is shelterbelt forest capable to resist wind and drought? (critique on monoculture practice)

Dialogue 2 - Is drought simply a consequence from climate change?

Dialogue 3 - A physical margin or perceptive margin?

Dialogue 4 -To plant or not to plant?

This study was made to investigate the reason for shelterbelt plantation die-off reported in the year 2009. Under the “Three-North Shelterbelt Plantation Programme”, large-scale plantations (i.e. ‘Green’) were widely used to combat desertification. Official records stress the importance of increasing the number of trees planted each year and the extent of green cover reclaimed. Regardless, the most common species planted, poplar, continues to experience high death rates. 

In Zhangbei, Northern China, extensive plantation areas declined following the 2009 drought. The issue of plantation die-off was widely reported in media, local county government explained the death resulted from forest age and drought. Is the issue simply a consequence of intensifying drought? Is this related to the design of shelterbelt plantation or others? 

Admittedly, the monoculture practice of shelterbelt plantation has a part to play. These plantation patches were designed in high density with porosity 60 to 70%. Plantation forests in Zhangbei were established nearly 40 years. (Wang et.al. 2012) With spacing 1m per tree and 2m per row, trees are all planted at the same time to resist strong wind. The simple structure and monotonous gene increase their vulnerability to climate change and pest attack. Populus simonii, a water-demanding specie exotic to Zhangbei. Over years of plantation, the tree lowered the water table by 0.3m every year. Eventually, the land dries up and trees fell. (Yang Jian-Wei, et.al. 2004)​​​​​​​

Though climate records did reveal much extreme climate in recent years, drought in Zhangbei is greatly the result of land mismanagement and agro-pastoral intensification. Zhangbei is an agro-pastoral zone primarily a savannah grassland ecosystem. Historically, the land was used extensively by the nomads for grazing. It is not until the Mao’s era, the land was opened up for agricultural use. With one-third of land converted to farmland, irrigation systems consumed almost 90% of water resources. Drought became visual with the drying-up of Angulinao lake, which showed record of occasional dry-up in the past and completely disappeared in 2004. Acknowledging the problems created by agricultural intensification, the county government introduced the “Grain for Green” as a strategy to restore green cover in the region. 

Zhangbei sits at the transitional zone between the northern Mongolian desert and Daxingshan ranges where the semi-arid meets with non-arid region. Preserving such boundary receives high attention by the state because it is widely believed by preserving the ranges, the impact of desertification can be eliminated and nearby cities can be protected, including the capital Beijing. At the lee side of the ranges, patches of plantation forests were established under the “Three-North” for soil stabilization. 

The issue of Poplar’s die-off rejects this common belief. Apart from creating instant green effect, the approach is not resolving desertification. It fails to address the underlying causes that exacerbate the change. This margin of desertification is physically unstable and the ‘Green’ is rather political measure instead of ecological. Green plantation area remains fragmented regardless the government’s effort in reclaiming land from farmland.

The issue of plantation die-off reveals shelterbelt’s failure to stop the desert. The above questions need to be rethink with a critical eye on the principle of ‘green’. The case in Zhangbei demonstrates a fundamental fallacy of using shelterbelt as a tool to modify landscape and microclimate to sustain local agriculture, where the real cause of drought remains intensive farming on marginal landscape.

In fact, the successfulness of restoration does not come in terms of what to plant or where to plant. It underlies decision making in the entire process of recovery. Starting with the trees, it is more important to design a community-based system to sustain with the process, to balance the need for local people during the process of recovery. The above images suggest a less intensive use of marginal landscape, under careful consideration on the productivity of savannah grassland.