2.1. Area Description
The IMAR is located in the southern part of the Mongolian Plateau, which covers an area of approximately 11.8 million km2
with an elevation between 86–3522 m. The IMAR is characterized by an arid to semi-arid continental climate [16
] with strong climatic gradients and grass land-use dominated practices (Figure 1
). Precipitation decreases and temperature increases from east to west ranged from 100 mm to 500 mm. The annual mean, minimum and maximum temperatures in the IMAR are 1.6, −18.3, and 18.7 °C, respectively [17
]. The IMAR is more than 70% covered with native grassland ecosystems, which corresponds to 20% of China’s total grassland area [18
]. Typical steppe and meadow steppe are the major types of grassland ecosystems found in the IMAR, and are most commonly used for grazing and animal production, especially in the last 20 years [11
]. In the northeast, meadow steppe is the most productive type of grassland ecosystem [16
], developing in areas with moist fertile soils rich in organic matter and includes Stipa baicalensis
, L. chinensis
, and Cleistogenes mucronata
]. The north central area of the IMAR borders the semi-desert and is dominated by typical steppe [20
]. Typical steppe is capable of drought tolerance, and includes Stipa grandis
, Leymus chinensis
, and multiple species of Artemisia
. The southwestern area is dominated by semi-desert steppe, in which is the most arid ecosystem, with the least biomass [16
]. Some of the species found include perennials such as Stipa krylovii
, Stipa bungeana
, and Artemisia ordosica
The geographic location and coverage rate of grassland in the IMAR.
The geographic location and coverage rate of grassland in the IMAR.
Grassland degradation is a widely observed problem, and estimates for the IMAR’s grassland reported 30%–50% to be degraded [20
]. In a semi-arid region like the IMAR, available water through the hydrological process undoubtedly plays a key role in the functioning of the grassland ecosystems. The effects of water use mechanisms are extremely important to grassland degradation. For example, water shortages affect water transport through changing the soil physical structure and energy balance of the soil, affecting the performances of plant species and root architecture, with consequences for degradation [3
].To reverse the increasing tendency toward water stress and grassland degradation, a series of policies and countermeasures have been put forward and enforced to alleviate the anthropogenic stress at national to household levels in the last decade, the most important of which implemented in badly degraded areas is called the “Returning Grazing to Grassland” restoration policy [22
]. The grassland restoration policy was brought out around 1998 and broadly extended after several years of experimentation, and the herders’ livelihood has been significantly affected through the implementation of the policy. The main measures of this policy are seasonal grazing and rotational grazing (e.g., in Hulun Buir), grazing prohibition and limiting thenumber of livestock according to the carrying capacity of degraded grassland (e.g., in Xilin Gol and Ordos).
Increasef agriculture water consumption for food provision will increase the water stress on the grassland ecosystems. From the statistics in 2010 and 1995, the IMAR’s total water resources amounted to 412.1 billion m3
, with a decrease of 24.5% from the level in 1995 (513 billion m3
). The region’s total water consumption in 2010 was 175.8 billion m3
, including agriculture irrigation water to 70.2% (123.4 billion m3
); next was industrial water consumption and urban domestic water consumption, which were 11.7% (20.5 billion m3
) and 4.8% (8.5 billion m3
); the ecological water consumption (water used directly for physiological processes of the ecosystem) was only 3.7% (6.5 billion m3
). Compared to the level in 1995, water consumption for agriculture increased significantly, three times higher (43.1 billion m3
in 1995) in 2010. We selected three typical sub-regions from southwest to northeast in the IMAR to capture gradient discrepancies in water resource consumption, including Dongsheng District and Ejin Horo Banner (in Ordos), located in the south-west of the IMAR and mainly characterized by semi-desert steppe, Zhangxiangbai Banner (in Xilin Gol) located in the central IMAR and characterized by typical steppe, and Evenk Banner (in Hulun Buir) located northeast of the IMAR and characterized by meadow steppe (Figure 1
). The spatial distribution of water resources is different. In Hulun Buir has abundant water resources, but utilization is extremely low and about 60%–80% of total annual precipitation falls between June and September; Ordos has serious problems with water shortages due to the dry climate. In Xilin Gol, the proportion of agricultural water (agriculture water includes three parts: (1) irrigation water (rainfall, artificial watering); (2) water use for animal husbandry (animal drinking water, animal and manure cleaning); and (3) cleaning water for agricultural product processing.) is large, in which leads to issues from excessive extraction of groundwater for most cities and rural areas [23
]. Therefore, water resource stress is serious, especially in the central and western areas of the IMAR.
Major land use types include grassland, arable land, forest and others (including unban area, water body and wetland) (Figure 1
and Table 1
). The percentages of land use in the three sub-regions are distributed differently and statistical data of invested banners or districts were explored to distinguish the differences between land uses. In Evenk Banner, the grassland and forest are the majority of land use and occupied 56.8% and 34.6% of total land. The arable land only accounts 0.9% of total land. Evenk Banner is a traditional pastoral area and is famous for livestock and poultry cultivation. The Hulun Buir has become the largest milk and meat export center in China. In Zhengxiangbai Banner, the grassland dominates 94% of total land, and the percentage of arable land is larger than Evenk Banner (accounts 2.2%); more than half of them grow grains. The forest area in Zhengxiangbai Banner has a lowest percentage, only 1.5%. Half of Zhengxingbai Banner is a traditional pastoral area and half is a farming area. In recent years, the scale of cultivation has been greatly increased, from livestock husbandry from traditional farming to modern cultivation. Dongsheng District and Ejin Horo Banner in Ordos were investigated; grassland was still the dominant land use, 67.4% and 60.7%, respectively. The second largest area was forest, 27.1% in Dongsheng District and 33.1% in Ejin Horo Banner. Dongsheng District and Ejin Horo Banner take the leading role for booming economic development with the rapid development of mining. The general trend in livestock husbandry and crop farming activities is moving away from individual participation to larger-scale operations, and the population engaged in husbandry and farming has decreased greatly over the last 15 years.
Land use patterns in the study sites.
Land use patterns in the study sites.
|Land Use||Hulun Buir (ha)||Xilin Gol (ha)||Ordos (ha)|
|Evenk Banner||Zhengxiangbai Banner||Dongsheng District||Ejin Horo Banner|
|Grassland||1,063,013 (56.8%)||585,700 (94.0%)||203,000 (67.4%)||435,593 (60.7%)|
|Arable land||16,436 (0.9%)||13,867 (2.2%)||7865 (2.6%)||31,891 (4.4%)|
|Of which: grain||9245 (0.5%)||7066 (1.1%)||5735 (1.9%)||21,621 (3.0%)|
|fruit-vegetable||269 (0.0%)||2667 (0.4%)||103 (0.0%)||3841 (0.5%)|
|Forest||647,160 (34.6%)||9087 (1.5%)||81,670 (27.1%)||238,000 (33.1%)|
|Others *||143,386 (7.7%)||14,246 (2.3%)||8654 (2.9%)||12,471 (1.7%)|
In the past two decades, the IMAR’s human population and its GDP grew significantly. According to the Chinese sixth census, the total population of the IMAR was 24.71 million people in 2010, compared with the fourth census of 21.46 million people in 1990, a total increase of 3.25 million people, with a growth rate of 13.15%. However, the rural population has decreased, especially in Ordos. According to the report of Chinese National Statistic Bureau, the total immigrated population in the IMAR from rural to city increased by 0.48 million from 1997 to 2006. In 2013 the IMAR’s GDP totaled 2.71 × 1012
USD, an enormous increase from the estimated 2.56 × 109
USD in 1987 [24
]. Farming and animal husbandry, particularly sheep and goat herding, are the traditional approaches for subsistence. However, emphasis on industrial and economic growth during the last two decades has greatly transformed in the IMAR, and caused increasing pressure on natural ecosystems. The ability to maintain a balance between economic growth and ecosystem stability, and thus foster long term societal sustainability, has become a serious challenge facing the people of the IMAR.
2.2. Research Design, Questionnaire and Data Collection
A survey of 209 households (n ≈ 70 per sites) was conducted by questionnaire surveys to assess their direct water and food consumption. In addition, information on household characteristics and major production activities were collected to assess the total water consumption per household. We used a stratified random sampling method [26
] to select the villages in our study. We selected three villages in Hulun Buir (Evenk Banner), two villages in Xilin Gol (Zhengxiangbai Banner) and four villages in Ordos (Dongsheng District and Ejin Horo Banner). The survey was conducted from June to July 2010; simple random sampling was adopted for the household survey. For each household we visited, we asked the head of each household or a family member who was familiar with the household to answer the questions. We interviewed over 65% of total households and 70% of total population of each village with appropriate sample sizes based on the suggestion of Tabachnick and Fidell [27
] that a sample should be over 50% when the total households of the survey unit group are lower than 100. Because the survey was carried out using face-to-face interviewing of the respondents or having the respondents complete the questionnaires under the research group members’ guidance, we obtained a high response rate of 90.5%.
Prior to the formal surveys, we conducted test surveys using individual interviews and family group discussions with herders and other key informants, and the information collected in the test surveys guided the development of the formal questionnaire. Closed-ended questions were primarily applied for a formal survey, which included questions in the following areas: (a) demographics, land characteristics, financial conditions and the socioeconomic characteristics of the households related to household composition, levels of education, livestock owned, the area cultivated and crops grown; (b) their consumption of domestic water and food in 2010; (c) their consumption of domestic water and food around the year 1995 (as recalled by the respondents). Because a series of policies and counter-measures of grassland restoration have been put forward and enforced around 1998, this intervention may cause great changes in the use of natural recourses and its subsequent issues. In China, many data are updated every 5 years. This is why 1995 (before restoration policy) and 2010 (recent, after restoration policy) have been chosen to make comparisons. In the survey, we asked the households to categorize and quantify the foods they had consumed in the year prior to the survey (2010) and 15 years ago (1995). In this case, 15 foods as basic food types for consumption have identified according quantities of household food consumption for the analysis, namely wheat, rice, glutinous millet, potatoes, vegetables, fruit, cooking oil, bean products, mutton, beef, pork, chicken, fish, milk products and eggs. The respondents reported the variety and quantity of the consumed foods. These 15 foods were further grouped into seven categories based on clarification of Chinese dietary guidelines (2007), namely staple foods (wheat, rice and glutinous millet), potatoes, vegetable-fruit, mutton-beef, other meats (pork, chicken and fish), oil-bean products and milk-eggs. Quantities of consumed food include home grown food and purchased. The survey revealed that households could accurately recall their consumptions in the year prior to the survey and the main consumption patterns in 1995.