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The current agroecological transition of agriculture pushes to a diversification of cropping systems, which requires quantified data describing crop successions. "Crop successions indicators 2015-2021" dataset provides a set of twenty synthesis indicators to characterize crop diversity, crop seasonality, particular components of crop successions and duration of crop rotations. Indicators are computed for a seven-year period from 2015 to 2021. Data source are raw crop sequences open access dataset. Indicators are available for municipalities, departments, regions and the whole mainland France, for arable land. A group of experts in agronomy has been associated to this work, in order to define relevant themes, relevant indicators and relevant indicator definitions. This dataset could be useful to characterize agricultural practices on a given territory, for researchers, local actors as decentralized state services, water agencies, territorial collectivities, chambers of agriculture, or agricultural cooperatives. Proposed indicators could be useful for policy makers to monitor the evolution of cultivation practices, in order to design, implement or evaluate measures targeting cultivation practices.
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The arable land abandonment caused by the large-scale non-agricultural transfer of labour has attracted substantial attention from all walks of life in China. Promoting improvement in human settlement environment can accelerate the construction of infrastructure, ameliorate grassroots organization and enhance management capacities while simultaneously decelerating agricultural production costs. High level of human settlement environment can also attract the labour force to return, stimulate the vitality of rural elements and endogenous powers. Then, can improving rural human settlement environment alleviate the phenomenon of arable land abandonment caused by non-agricultural labour transfer? In order to answer this question, based on the micro-survey data of 1325 households in 5 provinces of China, this paper uses the Tobit model to empirically test the effects of rural human settlement environment and non-agricultural transfer of labour on arable land abandoned. The results revealed that rural human settlement can alleviate the arable land abandonment caused by non-agricultural transfer of labour to a certain extent. In particular, the improvement of rural human settlement environment that mainly based on the infrastructure construction and organizational management level, has significantly alleviated the arable land abandonment caused by the non-agricultural transfer of labour. Heterogeneity analysis disclosed that, compared with mountainous and hilly areas, the improvement of rural human settlement environment had a more obvious mitigation effect on arable land abandonment in plain areas. Promoting infrastructure construction and strengthening organizational management ability were effective ways to alleviate arable land abandonment in plain areas. Farmer households with high place attachment level were more likely to be attracted by the improvement of rural human settlement environment to return to their hometown, so as to make use of arable land resources. Improving infrastructure, strengthening organizational management level, and promoting cultural and community development were the main measures for farmer households with high place attachment level to reduce arable land abandonment. In addition, there were significant differences in arable land abandonment and its driving factors in different regions. In the central and eastern regions or major grain-producing areas, improving human settlement environment had a significant mitigation effect on arable land abandonment. Therefore, improving the rural human settlement environment according to local conditions, promoting the supportive policy will be inclined to mountainous and hilly areas, enhancing the attractiveness of rural areas, encouraging farmers with high place attachment level to return to their hometowns for employment and entrepreneurship, and accelerating the cultivation of new types of agricultural operators, which will help alleviate the arable land abandonment caused by non-agricultural transfer of labour.
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Sustainable intensification (SI) of agriculture can produce more food to meet the demand of a growing population while considering ecosystem health. The current SI estimation framework ignores the complex coupling between input and output intensity of arable land. A method for coupled analysis of arable land input intensity and output intensity based on sliding windows is proposed. By calculating the correlation coefficient and partial correlation coefficient between input intensity and output intensity in different value ranges as the order parameter, the phase transition and the influence process of input intensity on output intensity can be explained. Meanwhile, a python-based framework is developed. An application of the method was made to reveal the interaction process between annual provincial input intensity and output intensity in mainland China. Researchers in many fields may benefit from the method by obtaining a fast way to analysis the coupling relationship between driving and dependent variables in complex systems.â¢New method for SI estimation is presented.â¢The order parameter of the coupling relationship between input and output intensity is calculated based on sliding windows.â¢Analysis of coupling relationships between driving and dependent variables in complex systems.
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Food security has a bearing on national development and people's livelihoods and is an important guarantee of social stability for national development. The problems of arable land abandonment and non-grain are becoming more and more serious, and national food security is difficult to guarantee, which will seriously hinder the forward development of China's society and economy. Taking Ruijin City of Jiangxi Province as an example, this study calculated the abandonment level and non-grain level of arable land in Ruijin City respectively from two aspects, and explored the spatial differentiation law of farmland abandonment and non-grain level in the hilly and mountainous areas of southern Jiangxi Province by using spatial autocorrelation and cold and hot spot analysis methods, and the causes of arable land abandonment and non-grain spatial differentiation in the hilly mountainous areas of Gannan were revealed by the methods of Geodetector factor detection and interaction detection. Conclusions of the study: (1) Ruijin City, the abandoned area was 1216.73 hm2, the abandonment rate of each village ranged from 0.01 % to 50.62 %, and the comprehensive abandonment rate was 4.90 %; the area of non-grain was 2937.27 hm2, and the rate of non-grain of each village ranged from 0.01 % to 100.00 %, and the comprehensive non-grain rate was 11.83 %. The area of non-grain was 2937.27 hm2, and the rate of non-grain in each village ranged from 0.01 % to 100.00 %, and the comprehensive rate of non-grain was 11.83 %. (2) The phenomenon of abandonment of arable land and non-grain in Gannan hilly and mountainous areas has a certain clustering and driving effect in space. Globally, the phenomena of arable land abandonment and non-grain in Ruijin City are positively correlated, with the global Moran's I of arable land abandonment rate being 0.05, and the global Moran's I of arable land non-grain being 0.73. (3) Whether or not arable land in the hilly mountainous areas of Gannan is abandoned is affected by the combination of socioeconomics, natural resources, farming conditions, and economic location, with elevation, the degree of arable land contiguity, and population density being the dominant factors. The interaction of elevation, degree of concentration and contiguity, field regularity, and per capita arable land area increased the spatial variability of arable land abandonment in the hilly mountainous areas of Gannan. Whether the phenomenon of non-grain occurs or not is affected by socio-economic conditions, farming conditions and economic location, of which the proportion of paddy fields, land transfer price, arable land area, and urban-rural gradient are the dominant factors. The proportion of paddy land, the price of land transfer, the area of arable land, and the urban-rural gradient interact with each other, and the tendency of arable land to be planted with non-grain crops is more serious.
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In this study, a Meta-analysis was used to investigate the pollution status of eight farmland soil heavy metal elements (As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn) in China. Meanwhile, their spatiotemporal changes and differences between different types of cultivated land were explored. The research data were chosen from 449 relevant literature data collected by CNKI and Web of Science from 2005 to 2021, and the Meta-analysis used a weighted method based on "sampling numbers", "study area", and "standard deviation". The results showed that the national average values of the eight heavy metal elements in Chinese farmland soil were ω(As)11.00 mg·kg-1, ω(Cd)0.350 2 mg·kg-1, ω(Cr)62.91 mg·kg-1, ω(Cu)28.87 mg·kg-1, ω(Hg)0.135 1 mg·kg-1, ω(Ni)28.91 mg·kg-1, ω(Pb)34.67 mg·kg-1,and ω(Zn)90.24 mg·kg-1. Compared with their background values, all elements except As accumulated to some extent, and Cd and Hg accumulated the most, exceeding their background values by 177.9% and 340.3%, respectively. The research results indicated that Cd and Hg were the main pollution elements in farmland soil in China, and their accumulation was mainly influenced by human activities. In terms of their temporal and spatial changes, the Yunnan-Guizhou Plateau and the eastern coast were the most concentrated areas of pollution cases, and the pollution center shifted from the middle reaches of the Yangtze River to the southwest over time. The accumulation of heavy metals in farmland soil was affected by crop planting types, and the accumulation of heavy metals in vegetable and paddy soil was significantly greater than that in other cultivated land types.
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Mercurio , Metales Pesados , Contaminantes del Suelo , Humanos , Suelo , Granjas , China , Cadmio , Plomo , Monitoreo del Ambiente/métodos , Medición de Riesgo , Contaminantes del Suelo/análisis , Metales Pesados/análisisRESUMEN
Inter-regional trade of agricultural products based on the flow of agricultural virtual resources is of great importance for sustainable agricultural development. We focused on grain crops (rice, wheat and maize) in the North China Plain (NCP), and used the Penman-Monteith equation to simulate crop water requirements. We further analyzed the flow of virtual land and virtual water associated with the grain trade using an environmentally expanded multi-regional input-output model. The coupling coordination of land, water, and food was evaluated to assess the rationality of regional agricultural production resource allocation. Between 2007 and 2017, agricultural virtual land and virtual water embodied in the grain trade between the NCP and other areas increased by 48.10 % and 34.41 %, respectively, indicating that the NCP is gradually consolidating its position as the main production area and distribution center of crops in China. Agricultural virtual resources in the NCP were mainly transported to the southeast coastal region, with an overall trend of resource movement from north to south. The total supply of agricultural land and water resources markedly increased in the NCP, whereas the transfer of virtual resources across regions showed a decreasing trend. Because of the irrational structure of crop cultivation and unevenness of regional resource allocation, the coupling coordination of the water-land-food nexus in the NCP is much lower than the national average. This study provides important information on the trade flows and coupling relationships of virtual water and land resources of three major food crops, which will help to alleviate resource pressure in agricultural production and promote sustainable agricultural development in the NCP.
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Arable land is facing the growing challenge of land degradation due to intensive use and this is beginning to affect global food security. However, active and passive restoration can improve soil characteristics and reshape microbial communities. Despite the increasing focus on changes in microbial communities during restoration, the mechanisms underlying how microbes drive the soil quality index (SQI) in arable land restoration remain unclear. In this study, we selected conventional farmland (CF, heavily intensified) and two restoration strategies (AR, artificial restoration; NR, natural restoration), with the same context (including soil texture, climate, etc.), and measured the microbial indicators over 2 years to investigate the mechanisms driving SQI improvement on restored arable land. The AR and NR treatments resulted in a 50% and 58% increase in SQI, respectively, compared to CF as soil nutrient levels increased, resulting in higher microbial biomasses and enzyme activities. Microbial abundance on the AR land was approximately two times greater than on the NR land due to the introduction of legumes. Bacterial diversity declined, while fungi developed in a more diverse direction under the restoration strategies. The AR and NR areas were mainly enriched with rhizobium (Microvirga, Bradyrhizobium), which contribute to healthy plant growth. The pathogenic fungi (Gibberella, Fusarium, Volutella) were more abundant in the CF area and the plant pathogen guild was about five times higher in the restored areas. Following arable land restoration, microbial life history strategies shifted from r-to K-strategists due to the higher proportion of recalcitrant SOC (DOC/SOC decreased by 18%-30%). The altered microbial community in the restored areas created new levels of functionality, with a 2.6%-4.3% decrease in bacterial energy metabolism (oxidative phosphorylation, C fixation, and N metabolism decreased by 7%, 4%, and 6%, respectively). Structural equation modelling suggested that restoration strategy affected SQI either directly by increasing total soil nutrient levels or indirectly by altering the microbial community and that fungal community composition and bacterial diversity made the largest contributions to SQI. These results provided new insights into soil quality improvement from a microbial perspective and can help guide future arable land restoration.
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Micobioma , Suelo , Bacterias/genética , Plantas , Biomasa , Hongos , Microbiología del SueloRESUMEN
The conflict between economic growth and the arable land demand poses a significant challenge to maintaining food security and achieving the Sustainable Development Goals. Meanwhile, substantial regional disparities in food consumption contribute to variations in land demand, further exacerbating constraints on food security. However, few studies have delved into regional differences in land demand related to food consumption. To bridge these gaps, this study estimated the arable land demand and associated pressures, considering food consumption patterns and the land footprint across 31 provincial districts in China. The findings reveal that grains remain the primary crop consumed by Chinese residents. Notably, the food consumption pattern exhibits substantial disparities among provincial districts, particularly concerning livestock products. Given China's vast population and escalating consumption of livestock, the country demonstrates heightened land demands. While China does not face a national-level food security threat, regional disparities are evident, with eight provincial districts facing potential food security risks. This study explored the challenges and pathways in maintaining food security and the visions to achieve it, emphasizing the importance of sustaining a balanced food consumption pattern, reducing food waste, improving environmentally friendly agriculture practices, formulating effective and continuous laws and regulations, and exploring potential land resource development to alleviate the pressure on arable land and ensure food security.
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Exploring the spatial relationship and ecological compensation mechanism of each function of arable land in poor mountainous areas is important to promote rural revitalization and enhance arable land protection. Taking the mountainous region of Western Hubei (MRWH) as an example, this study quantified the "three living" functions of arable land and its secondary functions. Using the root mean square deviation method to calculate the trade-off index, a quantitative method can more scientifically reflect the trade-off relationship between arable land functions and measure the overall ecological compensation. Studies have shown that (1) the value of the production function exhibits a growing and subsequently a falling trend, whereas the value of living function and ecological function exhibits an increasing trend over time, with an average functional value of 5310, 220 and 6496 million yuan, respectively. The spatial pattern of the "three living" functional values decreases from west to east. Among them, water conservation and soil conservation function values show a high distribution in the south and low in the north, gas purification and agricultural pollution functional values show a scattered spatial pattern, and the value of other functions shows an increasing trend from southeast to northwest; (2) among the primary functions, the trade-off between production and ecological functions is the strongest, decreasing, and then increasing over time, with an average trade-off index of 0.89. Among the secondary functions, there is the most obvious trade-off between the food supply function and the five ecological functions, which requires coordination; (3) overall, the total amount of ecological compensation has shown an upward trend, with priority areas for level I ecological compensation increasing year by year. Optimized compensation zones and potential compensation zones are concentrated in the northwest, ecological balance zones are located in the central part, and optimized development compensation zones and key development compensation zones are located in the southeast. According to the research, MRWH is oriented to ecological function, followed by the production function, supplemented by the living function. Green agriculture should be vigorously developed and ecological function space should be compressed by strictly limiting the excessive expansion of production activities. Promoting the improvement of production function through ecological function, while exploring the potential value of living function. Ecological compensation in strict accordance with the priority of ecological compensation, zoning. Realizing cross-regional cooperation, low compensation areas drive high compensation areas to achieve sustainable development of arable land.
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Conservación de los Recursos Naturales , Conservación de los Recursos Hídricos , Conservación de los Recursos Naturales/métodos , Suelo , Agricultura , Desarrollo Sostenible , China , EcosistemaRESUMEN
Agroforestry practices, such as hedgerow planting, are widely encouraged for climate change mitigation and there is an urgent need to assess their contribution to national 'net-zero' targets. This study examined the impact that planting hedgerows at different rates could make to UK net-zero goals over the next 40â¯years, with a focus on 2050. We analysed the carbon (C) content of native hedgerow species and determined hedge aboveground biomass (AGB) C stock via destructive sampling of hedges of known ages. AGB C stocks ranged from 8.34â¯Mg C ha-1 in the youngest hedges, to 40.42â¯Mg C ha-1 in old ones. Knowing the age of the hedgerows, we calculated their annual average AGB C sequestration rate, which was highest in young hedges (2.09â¯Mg C ha-1 yr-1), and lowest in 39â¯year old mature, regularly trimmed hedgerows (0.86â¯Mg C ha-1 yr-1). We present a time series of the annual AGB C sequestration rate change between hedge age categories, which increases from 2.09â¯Mg C ha-1 yr-1 in the first 6â¯years after planting, to 2.26â¯Mg C ha-1 yr-1 in the next 6â¯years, and then decreases to 0.43â¯Mg C ha-1 yr-1 between years 13 and 40. Our results indicate that, if encouraged widely, hedgerow planting can be a valuable tool for atmospheric CO2 capture and storage, contributing towards net-zero targets. However, current planting rates (1778.8â¯km yr-1) are too low to reach the net-zero goal set by the UK Climate Change Committee of increasing hedgerow length by 40â¯% by 2050. An increased planting rate of 7148.1â¯km yr-1 will achieve this goal by 2050, and, over 40â¯years, store 3.41 Tg CO2 in hedge AGB, or 10.13 Tg CO2 in hedge total biomass and in the soil, annually offsetting 1.5â¯%-4.5â¯% of UK annual agricultural CO2 emissions.
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Dióxido de Carbono , Secuestro de Carbono , Biomasa , Dióxido de Carbono/análisis , Agricultura , Suelo , Plantas , CarbonoRESUMEN
The countryside is a complex regional system with population and land as the core elements, and it is of great significance to study the coordination of the rural human-land relationship for promoting rural ecological protection and high-quality development. The Yellow River Basin (Henan section) is an important grain-producing area with dense population, fertile soil, and rich water resources. Based on the rate of change index and Tapio decoupling model, this study took county-level administrative region as the evaluation unit to explore the characteristics of the spatio-temporal correlation model of rural population/arable land/rural settlements in the Yellow River Basin (Henan section) from 2009 to 2018 and the optimal path of coordinated development. The results show the following: (1) The decrease of rural population, the increase of arable land in a relatively large part of non-central cities, the decrease of arable land in central cities, and the general increase in the area of rural settlements are the most important characteristics of the Yellow River Basin (Henan section) for the change of rural population/arable land/rural settlements. (2) There are spatial agglomeration characteristics of rural population changes, arable land changes, and rural settlements changes. Areas with a high degree of change in arable land have a certain degree of spatial consistency with areas with a high degree of change in rural settlements. (3) The type of T3 (rural population and arable land)/T3 (rural population and rural settlement) is the most important temporal and spatial combination mode, and rural population outflow is serious. In general, the spatio-temporal correlation model of rural population/arable land/rural settlements in the eastern and western sections of the Yellow River Basin (Henan section) is better than that in the middle section. The research results are helpful to deeply understand the relationship between rural population and land in the period of rapid urbanization and can provide reference for the classification and sub-standard policies of rural revitalization. It is urgent to establish sustainable rural development strategies for improving the human-land relationship, narrowing the rural-urban disparity, innovating rural residential land area policies, and revitalizing the rural area.
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Ríos , Población Rural , Humanos , Urbanización , Suelo , Desarrollo Sostenible , China , Conservación de los Recursos Naturales/métodosRESUMEN
For mountainous areas in different regions, the study of the spatial coupling relationship between rural settlements and arable land resources is a key aspect of coordinated rural development. In this study, a spatial coupling relationship model and a Geodetector are introduced to explore the spatial coupling relationship and driving factors of rural settlements and arable land in the alpine canyon region. The nearest neighbor index, Voronoi diagram, and landscape pattern index system based on the geographic grid are used to analyze the spatial differentiation characteristics of rural settlements in the alpine canyon region, and the spatial coupling relationship model is introduced to explore the spatial coupling relationship between rural settlements and arable land. Finally, the driving factors of the coupling relationship are detected based on Geodetector. The results show that (1) the spatial distribution of rural settlements in the study area is "T-shaped" with a relatively regular settlement shape; (2) the population in the alpine canyon region is relatively small, and the conflict between people and land is not prominent in most areas, so the overall coupling situation between rural settlements and farming land is dominated by fewer people and more land; and (3) the spatial coupling between rural settlements and arable land in the alpine canyon region is mainly affected by four types of factors: terrain topography, meteorology, soil and population, and economy. The interaction between the factors has a synergistic enhancement effect. The results of the study provide theoretical support for the development of rural settlements in the alpine canyon region.
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Población Rural , Suelo , Humanos , ChinaRESUMEN
The abandonment phenomenon is familiar in China. It threatens food security and seriously affects the sustainable development of society, the economy, and the natural environment. However, monitoring and mapping abandoned cropland on a large scale remains a challenge because of its complex land-use change process. According to the World Food and Agriculture Organization, cropland not used for agricultural production for more than 5 years is defined as abandoned cropland. This study uses the Landsat high-precision long-time series product to detect cropland nationwide from 1990 to 2019 by using the sliding window method on Google Earth Engine to profile the spatial distribution, intensity, trend, frequency, and recultivation of abandoned cropland. Between 1992 and 2015, the results illustrate that the total area of abandoned cropland in China was 559,170.26 km2, 18.59 % of the cropland area. Excluding the recultivated cropland area, China's abandoned cropland area amounted to 392,156.24 km2, 13.03 % of the total cropland. Cropland abandonment is mainly distributed in the second terrain gradient in midwestern and southwestern regions such as Inner Mongolia and Gansu. It rarely happens in western and eastern coastal areas. A high abandonment rate area usually has high elevation and slope. The light index is negatively correlated with the abandonment rate in suburban areas. This study is the first to map the spatiotemporal distribution of abandoned cropland in China with high precision at 30 m resolution. It provides an important basis for policies regarding the recultivation of abandoned cropland.
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Agricultura , Productos Agrícolas , Agricultura/métodos , ChinaRESUMEN
Arable land protection is critical to the sustainable development of agriculture in China and acceleration of the realization of the trinity protection goal of the quantity, quality, and ecology of arable land. As a new program of behavioral science to promote social development, nudge has gradually gained the favor of researchers and policy makers due to its unique advantages of small cost and substantial effect. However, current research and practical exploration of arable land protection behavior intervention based on the idea of nudging are still lacking. Implicit nudging strategies directly target the heuristic and analytic systems of arable land protection behavior of each stakeholder and possess more advantages than traditional intervention strategies. Therefore, this article designs six arable land protection behavior nudging strategies from the perspectives of cognition and motivation to realize the theoretical discussion of "generating medium-scale returns with nano-level investment". The nudging strategies of the cognitive perspective include default options, framing effects, and descriptive norms, while those of the motivation perspective aim to stimulate home and country, and heritage and benefit motives to promote arable land protection behavior of various stakeholders. The utility of nudge to arable land protection behavior may be controversial in practice. Therefore, the implementation in China should be based on the division of farmers, the number of options should be appropriate, and the external environment of arable land protection behavior should be fully considered.
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Agricultura , Conservación de los Recursos Naturales , China , Ecología , Agricultores , HumanosRESUMEN
Arable land abandonment has been occurring in China in recent years. Although an emerging number of studies have investigated the impacts of urbanization and labor migration on arable land abandonment, little is known about what roles agricultural outsourcing services play in reducing arable land abandonment. Based on the data from the China Labor-force Dynamics Survey (CLDS) in both 2014 and 2016, this study employs a two-stage least squares method to address the potential endogeneity issue and sheds some light on the impact of agricultural outsourcing services for controlling disease and pests in arable land abandonment in China. The empirical results show that disease and pest control outsourcing services (DPCOS) significantly decrease the size of household-level arable land abandonment by 6.59% on average. More specifically, DPCOS mainly reduce the arable land abandonment in regions with the labor shortages, while this does not lead to a significant decrease in arable land abandonment in regions characterized by poor soil quality and steep slopes. Therefore, we may conclude that DPCOS could contribute to the reuse of farmlands suitable for cultivation and the exit of farmlands unsuitable for cultivation.
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Servicios Externos , Agricultura , China , Control de Plagas , Suelo , UrbanizaciónRESUMEN
Vegetated land areas play a significant role in determining the fate of carbon (C) in the global C cycle. Riparian buffer vegetation is primarily implemented for water quality purposes as they attenuate pollutants from immediately adjacent croplands before reaching freashwater systems. However, their prevailing conditions may sometimes promote the production and subsequent emissions of soil carbon dioxide (CO2). Despite this, the understanding of soil CO2 emissions from riparian buffer vegetation and a direct comparison with adjacent croplands they serve remain elusive. In order to quantify the extent of CO2 emissions in such an agro system, we measured CO2 emissions simultaneously with soil and environmental variables for six months in a replicated plot-scale facility comprising of maize cropping served by three vegetated riparian buffers, namely: (i) a novel grass riparian buffer; (ii) a willow riparian buffer, and; (iii) a woodland riparian buffer. These buffered treatments were compared with a no-buffer control. The woodland (322.9 ± 3.1 kg ha- 1) and grass (285 ± 2.7 kg ha- 1) riparian buffer treatments (not significant to each other) generated significantly (p = < 0.0001) the largest CO2 compared to the remainder of the treatments. Our results suggest that during maize production in general, the woodland and grass riparian buffers serving a maize crop pose a CO2 threat. The results of the current study point to the need to consider the benefits for gaseous emissions of mitigation measures conventionally implemented for improving the sustainability of water resources.
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Agriculture contributes considerably to the increase of global greenhouse gas (GHG) emissions. Hence, magnitude and drivers of temporal variations in carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4) fluxes in croplands are urgently needed to develop sustainable, climate-smart agricultural practices. However, our knowledge of GHG fluxes from croplands is still very limited. The eddy covariance technique was used to quantify GHG budgets and N2O emission factors (EF) for pea and maize in Switzerland. The random forest technique was applied for gap-filling N2O and CH4 fluxes as well as to determine the relevance of environmental, vegetation vs. management drivers of the GHG fluxes during two cropping seasons. Environmental (i.e., net radiation, soil water content, soil temperature) and vegetation drivers (i.e., vegetation height) were more important drivers for GHG fluxes at field scale than time since management for the two crop species. Both crops acted as GHG sinks between sowing and harvest, clearly dominated by net CO2 fluxes, while CH4 emissions were negligible. However, considerable N2O emissions occurred in both crop fields early in the season when crops were still establishing. N2O fluxes in both crops were small later in the season when vegetation was tall, despite high soil water contents and temperatures. Results clearly show a strong and highly dynamic microbial-plant competition for N driving N2O fluxes at the field scale. The total loss was 1.4 kg N2O-N ha-1 over 55 days for pea and 4.8 kg N2O-N ha-1 over 127 days for maize. EFs of N2O were 1.5 % (pea) and 4.4 % (maize) during the cropping seasons, clearly exceeding the IPCC Tier 1 EF for N2O. Thus, sustainable, climate-smart agriculture needs to consider crop phenology and better adapt N supply to crop N demand for growth, particularly during the early cropping season when competition for N between establishing crops and soil microorganisms modulates N2O losses.
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Contaminantes Atmosféricos , Gases de Efecto Invernadero , Agricultura/métodos , Contaminantes Atmosféricos/análisis , Dióxido de Carbono/análisis , Productos Agrícolas , Gases de Efecto Invernadero/análisis , Metano/análisis , Óxido Nitroso/análisis , Pisum sativum , Estaciones del Año , Suelo , Agua , Zea maysRESUMEN
Since the adoption of the open-door policy, the Chinese dietary pattern has changed greatly. Based on the dietary changes, this study analyzed the arable land and water footprints (WFs) for the food consumption of urban and rural residents in China. The results showed that the arable land demand and WFs for meat, vegetable oil, soybeans and liquor exceeded those for other foods, and the per capita arable land and WFs for food consumption of urban residents were higher than those of rural residents. The total arable land and WFs for the food consumption of residents increased by 16.9 million ha (from 91.1 to 108 million ha) and 214.5 billion m3 (from 457.9 to 672.4 billion m3), respectively, from 1983 to 2017. Specifically, the total arable land and WFs for the food consumption of urban residents increased by 45.9 million hm2 (from 22.6 to 68.5 million hm2) and 318.3 billion m3 (from 113.2 to 431.5 billion m3), respectively. Additionally, those of rural residents decreased by 29.7 million hm2 (from 69.2 to 39.5 million hm2) and 103.9 billion m3 (344.8 to 240.9 billion m3), respectively, mainly due to the migration of the rural population to cities and the reductions in per capita arable land and WFs due to increased crop yields. The arable land and blue WFs required for food consumption will reach 127.7 million hm2 and 221.1 billion m3, respectively, in 2030. However, these values will be reduced by approximately 23% and 20%, respectively, to 98.9 million hm2 and 177.8 billion m3 under a balanced dietary pattern. Measures such as improving the investment in agricultural research and development, advocating a balanced diet, and increasing the import of resource-intensive foods could alleviate the pressure on land and water resources.
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Conservación de los Recursos Naturales , Población Rural , Agricultura , China , Conservación de los Recursos Naturales/métodos , Humanos , Agua , Recursos HídricosRESUMEN
Food security remains a major issue for developing countries. Reducing arable land abandonment (ALA) is crucial to ensuring food security. In China, the 'decline in both quantity and quality' of arable land resources, especially in major grain-producing areas, has become increasingly serious. This study uses fuzzy set qualitative comparative analysis (fsQCA) to explore the core conditions and combinations of paths leading to explicit and implicit abandonment using 30 typical cases in the main grain-producing areas of Hubei Province. The results show that (1) three combined pathways lead to explicit ALA (EALA) and that two pathways lead to implicit ALA (IALA); (2) laborer health (LH) is the core condition leading to EALA; and (3) LH, agricultural laborer (AL), per capita income (PCI) and social relationships (SRs) are the core conditions leading to IALA. To effectively alleviate ALA, the government should improve production conditions, pay attention to laborer health issues, improve agricultural returns and strengthen food security publicity and guidance, thereby promoting the rational use of arable land in these areas. The findings in this study link the changes in arable land use and provide a reference for other developing countries in ensuring food security.
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Agricultura , Conservación de los Recursos Naturales , China , Conservación de los Recursos Naturales/métodos , Grano Comestible , RentaRESUMEN
Manure amendments to agricultural soils is an excellent opportunity for sustainable utilization of agricultural waste while providing multiple benefits to improve soil quality and increase the availability of nutrients to plants, including phosphorus (P). In this study, a meta-analysis of published data from 411 independent observations based on 133 peer-reviewed papers was performed for an in depth understanding of various factors affecting the transformation of soil P pools with manure application. Manure application increased all soil inorganic P (Pi) by 58.0%-282% and organic P (Po) by 65.0%-105%, while decreasing Po/total P (TP), compared to those in unamended soils. Manure types, soil TP, and manure application rates were the important factors that influenced soil P fractions. Elevation of soil labile Pi was more pronounced with compost application, while poultry and pig manure were more beneficial for promoting soil Pi fractions and stable Po contents compared with other manure types. The manure application rate had pronounced effect on increasing the stable Po fractions. The effects of manure application on increasing soil P fractions were greater in soils with lower TP contents as compared to that in high TP soils. Manure effects on enhancing soil labile Pi and moderately labile Pi were greater in acidic soil than that in neutral and alkaline soils. In addition, soil P fractions showed significant correlation with latitude and mean annual precipitation (MAP). By integrating the impacts of manure types, soil properties, and climate, this meta-analysis would help to develop the management of manure application in a specific region of agriculture as well as promote the interpretation of the interfering factors on the soil P fractions changes in the manure-amended soils.