Farming-pastoral Zone Research Articles

Assessing Future Ecological Sustainability Shaped by Shared Socioeconomic Pathways: Insights from an Arid Farming–Pastoral Zone of China

Assessing Future Ecological Sustainability Shaped by Shared Socioeconomic Pathways: Insights from an Arid Farming–Pastoral Zone of China

Amelioration of habitat since the early Holocene contributed to the origin of agriculture in the farming-pastoral zone of northern China

Amelioration of habitat since the early Holocene contributed to the origin of agriculture in the farming-pastoral zone of northern China

Monitoring of Cropland Abandonment and Land Reclamation in the Farming–Pastoral Zone of Northern China

The farming–pastoral zone in northern China is one of the most ecologically sensitive areas globally, having experienced extensive cropland abandonment and land reclamation over decades, primarily influenced by policy adjustment and global warming. However, the spatiotemporal patterns and suitability of long-term cropland change remain poorly understood. Using the annual China land cover dataset (CLCD), we provide a cropland abandonment and land reclamation mapping approach based on actual land use processes (rather than land cover conditions) to investigate spatiotemporal features of abandonment and reclamation and evaluate the rationality. Our findings show that: (1) Returning farmland to forest and grassland has been a clear trend in the study area over the past 30 years. Specifically, cropland use has undergone three phases of change, i.e., cropland contraction and expansion alternately (before 2000), followed by substantial abandonment (after 2000), and low-intensity reclamation (after 2010). (2) In the last decade, the intensity of the abandonment of cropland with high and moderate suitability is low. The rate of abandonment decreased, while the intensity of land reclamation was relatively high. The rate of the reclamation increased, and the spatial distribution of cropland tended to be reasonable. Our study emphasizes the importance of monitoring actual cropland changes based on land use processes, and this method can be effectively extended to regional or global long-term cropland monitoring.

Identification of rural settlement development types in the farming-pastoral zone based on social network analysis

Identification of rural settlement development types in the farming-pastoral zone based on social network analysis

Changes in Climate Factors and Their Impacts on Wind Erosion Climatic Erosivity in Farming-pastoral Zone of Northern China

Changes in Climate Factors and Their Impacts on Wind Erosion Climatic Erosivity in Farming-pastoral Zone of Northern China

Drought sensitivity of vegetation photosynthesis along the aridity gradient in northern China

Satellite remotely sensed solar-induced chlorophyll fluorescence (SIF) enjoys the intrinsic superiority to the detection of ecosystem-level photosynthetic capacity under drought stress, yet little is known about how drought accumulation and legacy effects shape vegetation photosynthetic activities as approximated by SIF. Hence, we quantified drought sensitivity of vegetation photosynthesis (DSVP) by evaluating the degree and time to which SIF responded to prolonged and previous droughts with standardized precipitation evapotranspiration index (SPEI). Divergent SIF responses to SPEI across bioclimatic zones were examined in northern China for the period of 2000 to 2017. Our results suggested that the accumulation, legacy and their combined effects spread for 9.2, 25.0 and 44.3% of the vegetated land, respectively. The dominant lag and accumulation time of SIF responses to SPEI was 9.1 and 10.5 months for all biomes, respectively. In general, patterns of the cumulative and lagged effects along an aridity gradient were similar, displaying quicker and stronger SIF responses to SPEI in regions with a lower aridity index value, but the changing rate of magnitude and time duration varied among and within biomes. Besides, we detected a nonlinear response to increasing dryness in DSVP as reflected by multiple trend breaks, which were caused by the differences among vegetation types and their drought adaptation and vulnerability. Semi-arid ecosystems were found to be highly sensitive to drought, especially in the farming-pastoral zone with an aridity index value within 0.3–0.4. At the biome level, grasslands responded to prolonged and previous droughts quicker and stronger than croplands and deserts did, whereas forests were the least responsive. This study emphasizes the demand for a prompt assessment of drought impacts on vegetation photosynthesis in a drying climate, and to focus on regions where increasing dryness leads to substantial declines in photosynthetic capacity under global warming.

Winter Precipitations of Northern Part of Farming-Pastoral Zone and Hulunbuir Grassland

In January 2018, a high record of monthly total precipitation in northern China drew our attention. The precipitation amount is 4 times more than that in normal winters over the past 30 years. Up to now, many researches over the world focus on the intensity of precipitations or the number of intense precipitations, however, no sufficient study is investigated in the continuous moderate precipitations. The abnormal precipitation in January 2018 in northern China is a typical case of the continuous moderate precipitation. The research region is composed by the northern part of the farming-pastoral zone and the Hulunbuir Grassland. The main method in this study consists of analyzing the abnormal precipitation month by identifying the precipitation types and locations, and exploring the atmospheric circulations at the moment of typical precipitations. The research found that the continuity is the key point for high precipitation amount in January 2018 in Northern China. Besides, this continuity is caused by frequent appearance of cyclones in the vicinity.

The Environmental Impacts of the Grassland Agricultural System and the Cultivated Land Agricultural System: A Comparative Analysis in Eastern Gansu

“Introducing grass into fields”, the major approach to modern grassland agriculture, is the crucial direction of agricultural structure adjustment in the farming-pastoral zone of Northern China. However, there have been few studies on the environmental impacts of agricultural production in this pattern. We used the life cycle assessment (LCA) method for the first time from the perspective of the entire industry chain from agricultural material production to livestock marketing, which involves the combination of planting and breeding. A comparative analysis of the environmental impact processes of beef and pork, the main products of the two existing agricultural systems in Eastern Gansu, was conducted. The findings showed that based on the production capacity of the 1 ha land system, the comprehensive environmental impact benefit of the grassland agricultural system (GAS) in the farming-pastoral zone was 21.82%, higher than that of the cultivated land agricultural system (CLAS). On Primary energy demand (PED) and environmental acidification potential (AP), the GAS needs improvement because those values were 38.66% and 22.01% higher than those of the CLAS, respectively; on global warming potential (GWP), eutrophication potential (EP), and water use (WU), the GAS performed more environment-friendlily because those values were 25.00%, 68.37%, and 11.88% lower than those of the CLAS, respectively. This indicates that a change in land use will lead to a change in environmental impacts. Therefore, PED and AP should be focused on the progress of grassland agriculture modernization by “introducing grass into fields” and new agricultural technologies.

Reconstruction of cropland cover using historical literature and settlement relics in farming areas of Shangjing Dao during the Liao Dynasty, China, around 1100 AD

To improve the accuracy of historical cropland data, we reconstructed cropland cover in the northern China’s farming–pastoral zone during the Liao dynasty using historical literature and settlement relics. We first reconstructed the total cropland area using historical household data based on the cropland area per household. Next, we allocated the cropland area into 5′ grid cells weighted by settlement density to generate a cropland data. Our main findings were as follows: (1) Data on settlement relics enabled not only the identification of ancient farming areas but also the allocation of cropland cover within high resolution grids in the study area. (2) In the flourishing period of the Liao dynasty, the total cropland area was 0.39 × 104 km2. The cropland grids comprised 28.30% of the total grids, with average and maximum values of cropland fractions of 6.61% and 31.18%, respectively. (3) Compared with our result, we found that the PJ overestimate the cropland area of the study area in 1100 AD, whereas the HYDE 3.2 underestimate it. The area of anthropogenic land use in KK 10 was larger than the cropland area in this study too. None of the three global datasets revealed the mosaic spatial distribution pattern of cropland cover in this study area. (4) The orders of land suitability for cultivation during the Liao dynasty and the present period were almost the identical, even in the farming–pastoral zone of northern China, which has fragile ecological environment.

Impacts of land conversion and management measures on net primary productivity in semi-arid grassland

ABSTRACT Ecological restoration measures implemented in China have profoundly impacted vegetation NPP. This study aimed to estimate the effects of the land conversion and management measures on the grassland ecosystem in semi-arid regions. Land use data were employed from 2000 to 2015 to compare land conversion and coverage changes in Xilingol grassland. Then, the contributions of land conversion and management policies were quantified by assessing the difference between actual NPP and climate-induced NPP changes. The results indicated that the grassland area had a net loss of 534.42 km2, and the net area of increased vegetation coverage was 74,683.05 km2. Furthermore, the total NPP increased by 8,010.73 Gg C·yr−1 (1 Gg = 109 g), of which the human activities, including grazing management measures (+6,809.40 Gg C·yr−1) and land conversion (45.72 Gg C·yr−1) contributed to 85.58% of the increase in NPP. Transformation from desert and farmland dominated grassland expansion and NPP increase, while urbanization and desertification caused large grassland reduction and NPP loss. The grazing management increased vegetation NPP in most regions except for some regions in the desert steppe and the farming-pastoral zone. Related policies should be further adjusted to strengthen the management of the desert steppe and farming-pastoral regions.

Reply to the comment on “Effects of grazing exclusion on carbon sequestration in China's grassland”

How to understand the interactive influence of environmental changes on the total grasshopper density (TGD) becomes an urgent issue in grassland ecosystems. Large-scale studies are ideal for assessing the relative contributions of multiple factors on grasshopper community dynamics. Using data from 634 sites, linkages of community habitats (plant functional groups (PFGs), vegetative litter (VT) and soil types (ST)) and grasshopper occurrence were studied in a farming-pastoral zone across Inner Mongolia. Each of the three primary grassland ecosystem drivers influenced total grasshopper density. The absence of VT (VTabsence) can decrease the total grasshopper density by degrading the habitat conditions. Similarly, grasshopper communities prefer to feed on legumes and forbs rather than grasses due to the plant-trait variance in PFGs. Moreover, total grasshopper density was driven by complex interactions, caused by PFGs, soil types and vegetation litter. Our results improve the understanding of where grasshoppers might occur and provide helpful strategies to prevent the outbreak of grasshoppers.

Spatial variability of soil organic carbon in the West Liao River Basin

Quantification of the pattern and spatial distribution of soil organic carbon (SOC) is essential to comprehending many eco-hydrological processes. To obtain a better understanding of the spatial variability of SOC in a typical farming-pastoral zone, 270 soil samples were collected at 45 sampling sites from every 20 cm soil layer. Semi-variance function theory and ordinary Kriging interpolation were applied to identify the spatial variability of SOC. The results showed that SOC in the area was relatively low and decreased with depth and from the basin edge to the centre with a measured mean content of 0.07–0.65 g/kg. The strongest variability in the zone in the top soil layer (0–40 cm) was in the centre part of the zone, which was supposed to be the most concentrated area of human activities in the zone. As soil depth increase, the degree of variation of SOC decreased. Gaussian, exponential, and spherical models were suggested to successfully simulate SOC in different soil depth zones. The spatial distribution of SOC showed strong variability in the same soil depth zone, with a nugget to sill ratio of less than 14% and a range of 30–160 km.

Historical Arable Land Change in an Eco-Fragile Area: A Case Study in Zhenlai County, Northeastern China

Long-term land changes are cumulatively a major driver of global environmental change. Historical land-cover/use change is important for assessing present landscape conditions and researching ecological environment issues, especially in eco-fragile areas. Arable land is one of the land types influenced by human agricultural activity, reflecting human effects on land-use and land-cover change. This paper selected Zhenlai County, which is part of the farming–pastoral zone of northern China, as the research region. As agricultural land transformation goes with the establishment of settlements, in this research, the historical progress of land transformation in agricultural areas was analyzed from the perspective of settlement evolution, and the historical reconstruction of arable land was established using settlement as the proxy between their inner relationships, which could be reflected by the farming radius. The results show the following. (1) There was little land transformation from nonagricultural areas into agricultural areas until the Qing government lifted the ban on cultivation and mass migration accelerated the process, which was most significant during 1907–1912; (2) The overall trend of land transformation in this region is from northeast to southwest; (3) Taking the topographic maps as references, the spatial distribution of the reconstructed arable land accounts for 47.79% of the maps. When this proxy-based reconstruction method is applied to other regions, its limitations should be noticed. It is important to explore the research of farming radius calculations based on regional characteristics. To achieve land-system sustainability, long-term historical land change trajectories and characteristics should be applied to future policy making.

Linkages of plant-soil interface habitat and grasshopper occurrence of typical grassland ecosystem

How to understand the interactive influence of environmental changes on the total grasshopper density (TGD) becomes an urgent issue in grassland ecosystems. Large-scale studies are ideal for assessing the relative contributions of multiple factors on grasshopper community dynamics. Using data from 634 sites, linkages of community habitats (plant functional groups (PFGs), vegetative litter (VT) and soil types (ST)) and grasshopper occurrence were studied in a farming-pastoral zone across Inner Mongolia. Each of the three primary grassland ecosystem drivers influenced total grasshopper density. The absence of VT (VTabsence) can decrease the total grasshopper density by degrading the habitat conditions. Similarly, grasshopper communities prefer to feed on legumes and forbs rather than grasses due to the plant-trait variance in PFGs. Moreover, total grasshopper density was driven by complex interactions, caused by PFGs, soil types and vegetation litter. Our results improve the understanding of where grasshoppers might occur and provide helpful strategies to prevent the outbreak of grasshoppers.

Spatial and temporal variations of wind erosion climatic erosivity in the farming-pastoral zone of Northern China

Wind erosion climatic erosivity is an important parameter to assess the possible effects of climatic conditions on wind erosion. In this paper, the wind erosion climatic factor (C-factor), which was used to quantify the wind erosion climatic erosivity, was calculated for the period 1960–2014 based on monthly meteorological data collected from 101 stations in the farming-pastoral zone of Northern China. The Mann-Kendall (M-K) test, trend analysis, and geostatistical analysis methods were used to explore the spatial and temporal characteristics of the wind erosion climatic erosivity in this region. The result suggests that the annual C-factor, with a maximum of 76.05 in 1969 and a minimum of 26.57 in 2007, has a significant decreasing trend over the past 55 years. Strong seasonality in the C-factor was found, with the highest value in spring, which accounts for a significant proportion of the annual C-factor (41.46%). However, the coefficient of variation of the seasonal C-factor reaches a maximum in winter and a minimum in spring. The mean annual C-factor varies substantially across the region. Areas with high values of the mean annual C-factor (C ≥ 100) are located in Ulanqab and Dingxi, while areas with low values (C ≤ 10) lie in Lanzhou, Linxia, Dingxi, Xining, and Chengde. Spatial analysis on the trend of the C-factor reveals that 81% of the stations show statistically significant decreases at a 90% confidence level. An examination of the concentration ratio of the C-factor shows that the wind erosion climatic erosivity is concentrated in spring, especially in April, which makes this period particularly important for implementing soil conservation measures.

Accuracy assessment of seven global land cover datasets over China

Land cover (LC) is the vital foundation to Earth science. Up to now, several global LC datasets have arisen with efforts of many scientific communities. To provide guidelines for data usage over China, nine LC maps from seven global LC datasets (IGBP DISCover, UMD, GLC, MCD12Q1, GLCNMO, CCI-LC, and GlobeLand30) were evaluated in this study. First, we compared their similarities and discrepancies in both area and spatial patterns, and analysed their inherent relations to data sources and classification schemes and methods. Next, five sets of validation sample units (VSUs) were collected to calculate their accuracy quantitatively. Further, we built a spatial analysis model and depicted their spatial variation in accuracy based on the five sets of VSUs. The results show that, there are evident discrepancies among these LC maps in both area and spatial patterns. For LC maps produced by different institutes, GLC 2000 and CCI-LC 2000 have the highest overall spatial agreement (53.8%). For LC maps produced by same institutes, overall spatial agreement of CCI-LC 2000 and 2010, and MCD12Q1 2001 and 2010 reach up to 99.8% and 73.2%, respectively; while more efforts are still needed if we hope to use these LC maps as time series data for model inputting, since both CCI-LC and MCD12Q1 fail to represent the rapid changing trend of several key LC classes in the early 21st century, in particular urban and built-up, snow and ice, water bodies, and permanent wetlands. With the highest spatial resolution, the overall accuracy of GlobeLand30 2010 is 82.39%. For the other six LC datasets with coarse resolution, CCI-LC 2010/2000 has the highest overall accuracy, and following are MCD12Q1 2010/2001, GLC 2000, GLCNMO 2008, IGBP DISCover, and UMD in turn. Beside that all maps exhibit high accuracy in homogeneous regions; local accuracies in other regions are quite different, particularly in Farming-Pastoral Zone of North China, mountains in Northeast China, and Southeast Hills. Special attention should be paid for data users who are interested in these regions.

Research on land use optimization for reducing wind erosion in sandy desertified area: a case study of Yuyang County in Mu Us Desert, China

Desertification land occupies vast area of world, which is a big threat to eco-environmental safety and brings huge economic losses. Wind erosion is a key process and ecological problem of land desertification in arid and semi-arid area, where unreasonable land use is one of major causes. Therefore, optimizing land use is a substantially effective approach to eco-environmental safety and development of sandy area. Yuyang County, located in Mu Us Desert of semi-arid sandy area and farming-pastoral zone in North China, was selected as a typical study area. The principles and methods on environmentally friendly land use planning surrounding urban area for combating soil wind erosion were constructed, and a “tri-circle” land use paradigm around Yulin City was worked out. It was predicted that by the year of 2020, farmland will be only 10 percent of total area of Yuyang County, which are able to meet the need of food and meat. The proportion of ecological land, productive land and living land would be 2.27:12.09:85.64, which will lead to a reasonable land use system for ecological security and social-economic sustainable development of the region. It shows that this research will help construct the sustainable land use system under ecological security, and ensure habitat environmental safety in urban area.

Multi-Agent Modeling and Simulation of Farmland Use Change in a Farming–Pastoral Zone: A Case Study of Qianjingou Town in Inner Mongolia, China

Farmland is the most basic material condition for guaranteeing rural livelihoods and national food security, and exploring management strategies that take both stable rural livelihoods and sustainable farmland use into account has vital significance in theory and practice. Farmland is a complex and self-adaptive system that couples human and natural systems, and natural and social factors that are related to its changing process need to be considered when modeling farmland changing processes. This paper uses Qianjingou Town in the Inner Mongolian farming–pastoral zone as a study area. From the perspective of the relationship between household livelihood and farmland use, this study establishes the process mechanism of farmland use change based on questionnaire data, and constructs a multi-agent simulation model of farmland use change using the Eclipse and Repast toolbox. Through simulating the relationship between natural factors (including geographical location) and household behavior, this paper systematically simulates household farmland abandonment and rent behaviors, and accurately describes the dynamic interactions between household livelihoods and the factors related to farmland use change. These factors include natural factors (net primary productivity, road accessibility, slope and relief amplitude) and social factors (household family structures, economic development and government policies). Ultimately, this study scientifically predicts the future farmland use change trend in the next 30 years. The simulation results show that the number of abandoned and sublet farmland plots has a gradually increasing trend, and the number of non-farming households and pure-outworking households has a remarkable increasing trend, whereas the number of part-farming households and pure-farming households has a decreasing trend. Household livelihood sustainability in the study area is confronted with increasing pressure, and household non-farm employment has an increasing trend, while regional appropriate-scale agricultural management is maintained. The research results establish the theoretical foundation and a basic method for developing sustainable farmland use management that can meet the willingness of households and guarantee grain and ecological security.

Impacts of land use and land cover changes on biogenic emissions of volatile organic compounds in China from the late 1980s to the mid-2000s: implications for tropospheric ozone and secondary organic aerosol

Based on the MEGAN (Model of Emissions of Gases and Aerosols from Nature) module embedded within the global chemical transport model (GEOS-Chem), we estimate the changes in emissions of biogenic volatile organic compounds (BVOCs) and their impacts on surface-layer O3 and secondary organic aerosols (SOA) in China between the late 1980s and the mid-2000s by using the land cover dataset derived from remote sensing images and land use survey. The land cover change in China from the late 1980s to the mid-2000s can be characterised by an expansion of urban areas (the total urban area in the mid-2000s was four times that in the late 1980s) and a reduction in total vegetation coverage by 4%. Regionally, the fractions of land covered by forests exhibited increases in southeastern and northeastern China by 10–30 and 5–15%, respectively, those covered by cropland decreased in most regions except that the farming–pastoral zone in northern China increased by 5–20%, and the factions of grassland in northern China showed a large reduction of 5–30%. With changes in both land cover and meteorological fields, annual BVOC emission in China is estimated to increase by 11.4% in the mid-2000s relative to the late 1980s. With anthropogenic emissions of O3 precursors, aerosol precursors and aerosols fixed at year 2005 levels, the changes in land cover and meteorological parameters from the late 1980s to the mid-2000s are simulated to change the seasonal mean surface-layer O3 concentrations by −4 to +6 ppbv (−10 to +20%) and to change the seasonal mean surface-layer SOA concentrations by −0.4 to +0.6 µg m−3 (−20 to +30%) over China. We find that the decadal changes in meteorological parameters had larger collective effects on BVOC emissions and surface-layer concentrations of O3 and SOA than those in land cover and land use alone. We also perform a sensitivity simulation to compare the impacts of changes in anthropogenic emissions on concentrations of O3 and SOA with those of the changes in meteorological parameters and land cover.

Research on the Morphological Evolution of Sanye House Village Located in Farming-Pastoral Zone of Eastern Inner Mongolia

San ye House Village are located in Farming-pastoral zone of eastern Inner Mongolia after a hundred years of development history, from mainly nomadic settlements into agricultural and pastoral settlements. The evolution of the settlements' pattern experienced a total of three stages. With the combination of different periods of settlement pattern analysis, the characteristics of San ye House village settlement pattern development is studied and the reasons for its formation and evolution process are presented.