Agricultural Vulnerability to Drought in China's Agro-pastoral Ecotone:A Case Study of Yulin City,Shaanxi Province

Agro-pastoral ecotone of northern China is the prominent area for agricultural production,but it is also the most typical ecological fragile area with frequent drought disasters.Taking Yulin City at Shaanxi Province in China as the case area,the paper aims to investigate the spatio-temporal changes of agricultural vulnerability to drought in China’s agro-pastoral ecotone in the period 2000 to2020.The results show that:1)the agricultural vulnerability to drought in Yulin City has shifted from high vulnerability in the period2000–2010 to low vulnerability in the period 2011–2020.2)There exist obvious spatio-temporal differences of the agricultural vulnerability to drought in Yulin City during the research period.3)Four sensitive events and 14 resilient events were identified in the research and the crops of Yulin had become more resilient to drought.Finally,the paper put forward with policy implications to make adaptive strategies of agriculture to climate change in China’s agro-pastoral ecotone in the future,e.g.,carrying out agricultural zoning based on agricultural production conditions,intensifying the construction of disaster prevention and relief system,and integrating with modern agricultural technology to develop new type agriculture.

Impact of livelihood diversification of rural households on their ecological footprint in agro-pastoral areas of northern China

Human-environment relationship is a focus of academic researches and an understanding of the rela- tionship is important for making effective policies and decisions. In this study, based on rural household survey data of Taibus Banner, Duolun county and Zhengxiangbai Banner in the Inner Mongolia autonomous region of China, we identified the impact of livelihood diversification on ecosystems in these agro-pastoral areas by using the ecological footprint theory and methodology together with the one-way analysis of variance （ANOVA） and correlation analysis methods. In 2011, the total ecological footprint of consumption （EFC） was 0.665 g hm2, and the total ecological footprint of production （EFP） was 2.045 g hm2, which was more than three times the EFC. The ecological footprint of arable land consumption （EFAC） accounted for a large proportion of the EFC, and the ecological footprint of grassland production （EFGP） occupied a large proportion of the EFP. Both the ecological footprint of grassland consumption （EFGC） and EFGP had a significant positive correlation with the income, indicating that income was mainly depended on livestock production and the households with higher incomes consumed more livestock prod- ucts. The full-time farming households （FTFHs） had the highest EFP, ecological footprint of arable land production （EFAP）, EFGP and EFGC, followed by the part-time farming households （PTFHs） and non-farming households （NFHs）, which indicated that part-time farming and non-farming employment reduced the occupancy and con- sumption of rural households on local ecosystems and natural resources to some extent. When farming households engaged in livestock rearing, both the EFAP and EFAC became smaller, while the EFP, EFC, EFGC and EFGP increased significantly. The differences in ecological footprints among different household groups should be taken into account when making ecosystem conservation policies. Encouraging the laborers who have the advantages of participating in non-farming employment to move out of the rural areas and increasing the diversification of liveli- hoods of rural households are important in reducing the environmental pressures and improving the welfare of households in the study area. Moreover, grassland should be utilized more effectively in the future.

Changes in soil carbon stocks and related soil properties along a 50-year grassland-to-cropland conversion chronosequence in an agro-pastoral ecotone of Inner Mongolia,China

Land use change significantly influences soil properties. There is little information available on the long-term effects of post-reclamation from grassland to cropland on soil properties. We compared soil carbon （C） and nitrogen （N） storage and related soil properties in a 50-year cultivation chronosequence of grassland in the agro-pastoral ecotone of Inner Mongolia. Field surveys on land use changes during the period of 1955-2002 were conducted to build a chronosequence of cropland of different ages since the conversion from grassland. The results showed that soil C and N storage, soil texture, and soil nutrient contents varied with land use types and cropland ages （P〈0.01）. In the 0-30 cm soil layer, the soil organic carbon （SOC） density was significantly lower in the crop- lands （3.28 kg C/m2 for C50 soil） than in the grasslands （6.32 kg C/m2）. After 5, 10, 15, 20, 35, and 50 years of crop planting （years since the onset of cultivation）, the SOC losses were 17%, 12%, 19%, 47%, 46%, and 48%, respec- tively, compared with the grasslands. The soil total nitrogen （TN） density of the grasslands was 65 g N/m2, and TN density of the cropland soil was 35 g N/m2 after 50 years of crop planting. Both the SOC and TN densities could be quantitatively determined by a negative exponential function of cropland age （P〈0.0001, R2=0.8528; P〈0.0001, R2=0.9637）. The dissolved organic carbon （DOC） content, pH value were decreased; and the soil bulk density and soil available potassium （AK） content, clay content, and sand content were increased since the conversion of grassland into cropland during the 50-year period. Our results show soil nutrients were higher in grassland than in cropland. The conversion of grasslands to croplands induced a loss of soil C storage and changes of related soil properties. The reclamation time of cultivated soil （cropland age） had significant effects on soil properties in the study area.

Wavelet analysis of spring climate characteristics in arid aeolian area of agro-pastoral ecotone in China

The unique regional climate characteristics are among the main reasons for the frequent wind-sand activity in arid and cold areas in the agro-pastoral ecotone in Inner Mongolia, China. This paper focuses on the time series of temperature and precipitation in spring when sandstorms often occur in the area. Based on meteorological data for a 46-year period from 1959 to 2004, multi-scale variations and abrupt changes in temperature and precipitation were analyzed with the Mexican hat function （MHF） wavelet method, showing the multi-scale variation characteristics of temperature and precipitation, as well as the periods and change points at different time scales. The relationship between temperature and precipitation was obtained using the wavelet analysis method. Obvious staggered features of the variations of spring temperature and precipitation were observed in this agro-pastoral ecotone. The strongest oscillation periods of spring temperature variations were 1 and 22 years, while for precipitation, the strongest oscillation periods of variations were 2, 8, and 22 years. In addition, lower spring temperature corresponded to lower precipitation, whereas higher temperature yielded higher precipitation rate.

Livelihood Diversification of Farm Households and Its Impact on Cultivated Land Utilization in Agro-pastoral Ecologically-vulnerable Areas in the Northern China

The relationship between livelihood diversification of farm households and cultivated land utilization has become a core research topic related to global environmental change.Agro-pastoral ecologically-vulnerable areas face challenges such as insufficient ecosystem conservation,low agricultural production,and weak economies.In this study,215 farm households from Zhengxiangbai Banner,Taibus Banner,and Duolun County of Inner Mongolia were surveyed.The sustainable livelihoods framework of the United Kingdom(UK)Department for International Development(DFID)was used to measure the livelihood capital of these farm households.A one-way analysis of variance(ANOVA)was applied to examine the differences in the livelihood capital of different types households,and a correlation analysis was applied to analyze its impact on cultivated land utilization.Results showed that households with non-farming activities accounted for 64.7%of the total surveyed households,and non-farming employment was becoming more prevalent.Physical and financial capital was the driving factors for livelihood diversity.Each livelihood capital had key factors that affected household farmland use behaviors,such as the age of householder,the labor ratio,proportion of income,farmland scale,number of machines,and these had a significantly positive or negative influence on farmland use.Full-time farming households were more likely to transfer the land into cultivation and invest more labor,while non-farming households with high income were likely to transfer farmland out and invest more money to develop efficient farming or improve the employment skills.The results of this study suggest that policymakers need to fully consider livelihood changes of local households.It is effective to strengthen labor training,create farmland market and improve the efficiency of farmland utilization.We hope to achieve a win-win scenario to improve local economies and ecosystem conservation.

Impacts of Recent Climate Change on Dry-Land Crop Water Consumption in the Northern Agro-Pastoral Transitional Zone of China

Climate change has substantially impacted crop growth and development in the northern agro-pastoral transitional zone. Examination of the response of crop water consumption to climate change may provide a guide for adapting local agricultural production and ecological construction to new realities. The water consumption of three local crops （wheat, naked oats, and potatoes） is examined for Wuchuan County in the northern agro-pastoral transitional zone of China using meteorological data from 1960 to 2007 and soil moisture data from 1983 to 2007. The relationships between climate change and the crop water consumption are discussed. The results show that Wuchuan experienced both a warming trend and a reduction of precipitation between 1960 and 2007. The annual mean surface air temperature increased at a rate of 0.04℃ yr-1 and the annual precipitation decreased at a rate of 0.7 mm yr-1 . Both trends are particularly pronounced between 1983 and 2007, with an increase in annual mean temperature of 0.09℃ yr-1 and a decrease in annual mean precipitation of 2.1 mm yr-1 . Crop water consumption decreased between 1983 and 2007 for wheat （1.65 mm yr-1 ）, naked oats （2.04 mm yr-1 ）, and potatoes （3.85 mm yr-1 ）. Potatoes and naked oats consume more water than wheat. Climate change has significantly impacted crop water consumption. Water consumption and rainfall during the growing season are positively correlated, while water consumption and active accumulated temperature are negatively correlated. Compared to precipitation, accumulated temperature has little impact on crop water consumption. Recent climate change has been detrimental for crop production in Wuchuan County. Adaptation to climate change should include efforts to breed drought-resistant crops and to develop drought-resistant cultivation techniques.

Exploring the spatio-temporal impacts of farmland reforestation on ecological connectivity using circuit theory:A case study in the agro-pastoral ecotone of North China

Farmland reforestation can contribute substantially to ecological restoration.Previous studies have extensively examined the ecological effects of farmland reforestation,but few of them have investigated the spatiotemporal responses of broad-scale landscape connectivity to reforestation.By using a typical agro-pastoral ecotone in northern China as a case study,we addressed this issue based on an innovative integration of circuit theory approach and counterfactual analysis.The forest connectivity through multiple dispersal pathways was measured using the circuit theory approach,and its spatiotemporal changes after reforestation were evaluated by counterfactual analysis.The results showed that from 2000–2015,the reforested farmland occupied 2095 km^2,and 12.5% was on steeply sloped land.Farmland reforestation caused a greater increase in ecological connectivity by adding new ecological corridors and stepping stones in scattered forest areas rather than in areas with dense forest distributions.The newly added corridors and stepping stones were fragmented,short and narrow and thus deserve powerful protection.Future reforestation to improve landscape connectivity should highlight pinch point protection and obstacle removal as well as the tradeoff between farmland loss and farmer survival.Our findings are expected to inform the optimization of the Grain for Green policy from the perspective of broad-scale biodiversity conservation.

Impacts of regional land-use patterns on ecosystem services in the typical agro-pastoral ecotone of northern China

A comprehensive understanding of the spatial-temporal evolution and driving forces on ecosystem services(ES)is essential for the agro-pastoral ecotone’s ecological security in northern China.However,the land-use pattern(LULC)agglomeration with spatial differentiation in the pastoral and agricultural areas has been rarely concerned.Taking distinct LULC(1980-2018)in Chifeng as an example,we compared four crucial categories of ESs with InVEST.Using SEM,we further contrasted the effects of several variables on regional ES variations in pastoral-dominated(North)and agriculture-dominated(South)regions,respectively.Results revealed the conversion between forest and grassland oriented the LULC transformation in the North.In contrast,human-activitiy-oriented land tended to occupy environmentally sensitive places in the South.Similar ES variations were supplied with the North outperforming the South when soil conservation was omitted.As for the impacts of regional ES variations,the natural and LULC policies both showed positive effects,whereas the anthropogenic factors showed positive in the North,which was negative in the South.Therefore,the ecologicallymaintained-dominant and ecologically-restored-dominant strategies should be separately adopted in the North and South.Our study provided appropriate regional ecological management suggestions for balancing the LULC-driven conflicts between ecological protection and regional development.

The effects of land-use types and conversions on desertification in Mu Us Sandy Land of China

Based on multi-temporal remotely sensed materials of both 1985 and 2000, we analyzed the effects of land-use types and their conversions on desertification in Mu Us Sandy Land in the agro-pastoral transitional zone of north central China. In this study, the desertified land was classified into five degrees： potential, light, medium, severe and extreme. The results indicate that the extent of desertification expands slightly, while desertification degree is enhanced significantly. About 22.35% of the total land area in the study area is in the desertification course, and the expanded area of both severely and extremely desertified land accounts for 3.67% of the total area of Mu Us Sandy Land. About 9053 klTl2 of area witnessed changes in land-use types between 1985 and 2000, which accounted for 10.75% of the total. More importantly, the area of conversions among cultivated land, forestland and rangeland added up to 971.6 km^2. This research reveals that both improper land-use types and conversions could accelerate the desertification process. Both cultivated land and forestland have more effects on the desertification development than rangeland. Some land-use type conversions, such as rangeland to cultivated land, rangeland to forestland and forestland to cultivated land, are attributed to the acceleration of the desertification development while the opposite can control the desertification development.

Strategies for Prioritizing Ecological Construction with Consideration of Agricultural Industry Development in Northern China’s Agro- pastoral Ecotone : A Perspective of Opportunity Cost

In northern China’s agro-pastoral ecotone,there are conflicts between agricultural industry and ecological construction resource competition,and also problems urgently to be solved for economic growth and sustainable ecological improvement.Taking the development concept of"lucid waters and lush mountains being mountains of gold and silver"as the guiding principle of prioritizing ecological and green development,this paper studied the strategies for prioritizing ecological construction with consideration of economic development of agricultural industry from the perspective of opportunity cost.Through the analysis of opportunity cost,externality,and Pareto optimal theory,and using the calculation method of the unit equivalent factor value of terrestrial ecological service function,this paper calculated the ecological service value of forest,grassland,and farmland.It found that the ecological value of forest and grassland per unit area was greater than the ecological value of agricultural industry.This indicates that the opportunity cost of farmland for ecological construction was less than that of agricultural industry.Based on the theoretical and quantitative analysis,it came up with recommendations for establishing a comprehensive system for prioritizing ecological construction with consideration of agricultural industry development and establishing and improving the incentive mechanism of ecological construction.

Study on Management Practices and Constraints of Black Head Somali Sheep Reared in Awbarre District of Fafen Zone, Somali Region, Ethiopia

The study was conducted to assess management practices and constraints of Black head Somali sheep in Awbarre district of Fafen zone, Somali regional state, Ethiopia. A total of 120 households were purposively selected for this study using purposive sampling technique. The data were collected through the questionnaire, key informants interview, focus group discussions & field observations. The primary purpose of keeping sheep was for income generation followed by saving, meat production, milk, social and cultural functions. The main feeds for sheep during wet season were communal & private natural pastures. In dry season, communal natural pasture, crop residues & private natural pasture were used. The major source of water during wet season was dam/pond, whereas in the dry season spring & pipe water were used. The majority of the respondents (85.8%) used houses enclosed with thorn woody trees and houses enclosed with stone/brick fence were also reported. Majority of the respondents used controlled mating system and sheep are bred to lamb when forage is plentiful because they are less drought tolerant than goats and to avoid unwanted lambing in dry season. Majority (90%) of respondents own their breeding ram and those who have no breeding males used their neighbors’ rams and borrow from others. The breeding rams were born in the flock implying that animals within the flock are very closely related which leads to inbreeding. The most important health problems affecting sheep were circling disease, sheep pox, tick lameness (tick paralysis), Peste des Petits Ruminants (PPR), bloating, and Foot & mouth disease (FMD). The major constraints hindering sheep production in the study area were shortage of veterinary service, feed shortage, scarcity of water, predators, diseases, and marketing. Therefore, to improve and increase the productivity of sheep production in the study area, better management practices and establishing of veterinary service centers are necessary.

Canopy structure:An intermediate factor regulating grassland diversity-function relationships under human disturbances

Grasslands are one of the largest coupled human-nature terrestrial ecosystems on Earth,and severe anthropogenic-induced grassland ecosystem function declines have been reported recently.Understanding factors influencing grassland ecosystem functions is critical for making sustainable management policies.Canopy structure is an important factor influencing plant growth through mediating within-canopy microclimate(e.g.,light,water,and wind),and it is found coordinating tightly with plant species diversity to influence forest ecosystem functions.However,the role of canopy structure in regulating grassland ecosystem functions along with plant species diversity has been rarely investigated.Here,we investigated this problem by collecting field data from 170 field plots distributed along an over 2000 km transect across the northern agro-pastoral ecotone of China.Aboveground net primary productivity(ANPP)and resilience,two indicators of grassland ecosystem functions,were measured from field data and satellite remote sensing data.Terrestrial laser scanning data were collected to measure canopy structure(represented by mean height and canopy cover).Our results showed that plant species diversity was positively correlated to canopy structural traits,and negatively correlated to human activity intensity.Canopy structure was a significant indicator for ANPP and resilience,but their correlations were inconsistent under different human activity intensity levels.Compared to plant species diversity,canopy structural traits were better indicators for grassland ecosystem functions,especially for ANPP.Through structure equation modeling analyses,we found that plant species diversity did not have a direct influence on ANPP under human disturbances.Instead,it had a strong indirect effect on ANPP by altering canopy structural traits.As to resilience,plant species diversity had both a direct positive contribution and an indirect contribution through mediating canopy cover.This study highlights that canopy structure is an important intermediate factor regulating grassland diversity-function relationships under human disturbances,which should be included in future grassland monitoring and management.

土地工程及其在农牧交错区可持续农业中的作用——以陕西省榆林市为例（英文）

With global climate change, the agricultural light-temperature potential productivity in the agro-pastoral ecotone has increased. This offers a good opportunity to develop agriculture in the agro-pastoral ecotone. However, the agro-pastoral ecotone is also an ecologically fragile area in which land degradation challenges agricultural development. As population grows and the need for food increases, the land carrying capacity of the agro-pastoral ecotone becomes insufficient, and the human–land relationship is not harmonious. Such conditions have limited the agricultural and rural development in the ecotone. The paper demonstrates how land engineering may improve land quality and support agricultural development in the ecotone based on studies at a research station established in 2015 in Yulin,Shaanxi Province, China. The studies target three factors: soil improvement, crop selection,and field management. The results show that:(1) The highest yield of crops planted on improved land is close to or even higher than that achieved under previous crop growth conditions. For instance, the corn yields can exceed 25%.(2) The potatoes grown on the improved land yield the highest gross income, reaching 67,200 yuan/ha. By way of land engineering,input costs can be balanced in 3–5 years.(3) As a result of land engineering, some villages in Yulin City have realized sustainable agricultural and even rural development, and promotion of this model will support the sustainable development of agriculture in the agro-pastoral ecotone.