Impacts of Urban Expansion on the Loss and Fragmentation of Cropland in the Major Grain Production Areas of China

The continuous expansion of urban land has led to massive encroachment upon cropland. To examine the impacts of urban expansion on the loss and fragmentation of cropland in China’s nine major grain production areas (MGPAs), we used standard deviation ellipse, land use transfer matrix, land use dynamic degree, and landscape metric to explore the spatio-temporal evolutions, mutual transfer, and landscape patterns of cropland and urban land. The results show the following: (1) From 1995 to 2018, the areas of cropland in MGPAs showed a trend of “short-term increase—long-term decrease—short-term increase”, while that of urban land grew continuously; (2) Urban expansion is the main cause of cropland loss. The cropland area converted to urban land accounts for a large proportion (49.26%) of the total transfer of cropland to other land types, especially in the densely populated, rapidly urbanizing and industrializing Taihu Lake Plain, Jianghuai Region, and Pearl River Delta; (3) In most MGPAs, urban expansion has led to fragmentation of cropland, especially in the Pearl River Delta, as indicated by the significant change of patch density. However, in the Sanjiang Plain and Songnen Plain, a less pronounced or even reduced cropland fragmentation was observed due to the significant conversion of other land types to cropland under specific land policies. From these results, we suggest that the government should regulate the encroachment of urban land on cropland and the transfer of natural land to it, and encourage the rural land consolidation to increase the cropland.

Effect of variety and nitrogen fertilizer managements on the growth and yield of Transplant aman rice managements

Varietal selection and appropriate placement of nitrogen fertilizer could reduce the magnitude of nitrogen losses to a considerable extent and improve its use efficiency for better grain production. An experiment was carried out during the period from July to December at the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh to evaluate the effect of variety and nitrogen fertilizer management on the growth and yield of transplant aman rice. The treatments consisted of three varieties viz. BR11, BRRI dhan49 and Binadhan-7, and five nitrogen fertilizer managements viz. two depth of placement of USG (Urea Super Granule) and three split applications of prilled urea. The experiment was laid out in a randomized complete block design with three replications. The results showed that the effect of variety and nitrogen fertilizer management significantly influenced all the yield contributing characters except weight of 1000- grains, non-effective tillers hill-1 and panicle length. The highest grain yield (3.69 t ha-1) was obtained from Binadhan-7. In the case of nitrogen fertilizer management, the highest grain yield (4.32 t ha-1) was found from the 6 cm depth placement of USG. The highest grain yield (4.82 t ha- 1) was observed from the interaction of Binadhan-7 with the 6 cm depth of placement of USG. It may be concluded that Binadhan-7 with 6 cm depth of placement of USG appeared as the promising practice to maximize the yield of transplant aman rice. Res. Agric., Livest. Fish.8(3): 281-289, December 2021

Assessment of the sustainability of multipliers as the core of the region's agroeconomic system

This article examines the role of multipliers – subsectors of agriculture, as the core of the agroeconomic system of any region, using the example of the Ural Federal Okrug, and also evaluates their sustainability based on materials from 2010-2015. Three basic subsectors are analyzed as multipliers: grain production, dairy farming and poultry farming. As a result of the author's calculations using the appropriate methods, a conclusion was drawn about the dependence of the basic industries on each other, as well as on the market model in a particular territory.

Produksi Dan Kualitas Jerami Padi Sumber Hijauan Pakan Dengan Waktu Panen Dan Dosis Pupuk Berbeda

This study was aimed to analyze the fertilizer dosage and harvest age in Ciherang rice varieties to increase the rice straw production and quality. This study used a block randomized design with 3 x 4 blocks divided based on harvest age H1 = 114 days, H2 = 118 days and H3 = 122 days. The treatment was fertilizer dose level which consists of 4 levels, namely: P0 (control) = Urea 55 g+SP-36 5 g+KCl 6 g, P1= Urea 63,25 g+SP-36 5 g+KCl 6 g, P2= Urea 71,50 g+SP-36 5 g+KCl 6 g dan P3= Urea 79,75 g+SP-36 5 g+KCl 6 g. The variables observed were straw production, grain production, filled grain production, empty grain production, crude protein (CP), crude fiber (CF), Acid Detergent Fiber (ADF) and Neutral Detergent Fiber (NDF). Data were analyzed using analysis of variance followed by Duncan's Multiple Range Test. The results showed that P3 was significantly (p< 0.05) the highest among fertilizer dose level treatments on the straw production (27.63 tons ha-1), filled grain production (5.52 tons ha-1), and reduced empty grain (0.15 tons ha-1). The Quality of rice straw were CP 7.49%, CF 20.35%, ADF 55.03 %). While at harvest age, H1 was significantly (p< 0.05) the highest among harvest ages treatments on the variables of straw production 28.18%, empty grain production 0.21 tons ha-1) and NDF 69.11%. It can be concluded that the best fertilizer dosage was an addition of urea by 45% with harvesting age of 114 days. Key words: fertilizer, harvest age, production, quality, rice straw

Decoupling and Decomposition Analysis of Agricultural Carbon Emissions: Evidence from Heilongjiang Province, China

Ensuring food security and curbing agricultural carbon emissions are both global policy goals. The evaluation of the relationship between grain production and agricultural carbon emissions is important for carbon emission reduction policymaking. This paper took Heilongjiang province, the largest grain-producing province in China, as a case study, estimated its grain production-induced carbon emissions, and examined the nexus between grain production and agricultural carbon emissions from 2000 to 2018, using decoupling and decomposition analyses. The results of decoupling analysis showed that weak decoupling occurred for half of the study period; however, the decoupling state and coupling state occurred alternately, and there was no definite evolving path from coupling to decoupling. Using the log mean Divisia index (LMDI) method, we decomposed the changes in agricultural carbon emissions into four factors: agricultural economy, agricultural carbon emission intensity, agricultural structure, and agricultural labor force effects. The results showed that the agricultural economic effect was the most significant driving factor for increasing agricultural carbon emissions, while the agricultural carbon emission intensity effect played a key inhibiting role. Further integrating decoupling analysis with decomposition analysis, we found that a low-carbon grain production mode began to take shape in Heilongjiang province after 2008, and the existing environmental policies had strong timeliness and weak persistence, probably due to the lack of long-term incentives for farmers. Finally, we suggested that formulating environmental policy should encourage farmers to adopt environmentally friendly production modes and technologies through taxation, subsidies, and other economic means to achieve low-carbon agricultural goals in China.

Irrigation efficiency depending on water cost

The article provides an analytical review of the achieved crop yields under irrigation in experimental and production conditions. For today, the best production experience in the use of irrigated land indicates that, subject to all agrotechnical requirements, the yield of early grain crops reaches 8-10 t / ha, corn - 10-14 t / ha, oilseeds - 4-6 t / ha, vegetable crops - over 60 t / ha, which is about 90% of their productivity achieved in the experiments of scientific institutions. The comparative assessment of grain production in different climatic zones of Ukraine for the period of the most intense climatic change shows that over the past thirty years, the share of grain production in the Steppe zone has decreased from 45 to 35% of the total in Ukraine. The analysis of service cost for the transportation of water for irrigation in the southern regions of Ukraine is given. It was revealed that, despite a unified standard method for calculating the cost of water transportation, its price varies significantly by operational units of the State Agency for Water Resources of Ukraine. The main factors of fluctuations in the cost and fees for the transportation services of water for irrigation are the budgetary funding level of operating organizations, providing these services, the number of water transfers, the volume of actual irrigation on irrigated lands, the share of irrigated areas in the service area. The economic assessment of irrigation efficiency when having different water and other technological costs, taking into account the depreciation of capital investments, indicates that having a water price of 4,0-5,0 UAH/m3, the gross profit from growing the most profitable field crops is 35-40 % higher than the efficiency in rainfed agriculture. At the cost of water is 3,0-3,5 UAH/m3 and the use of the production capacity of the inter-farm irrigation network by 60-70%, financial prerequisites will be created for the effective operation of these networks.

Characteristics and Driving Forces of Non-Grain Production of Cultivated Land from the Perspective of Food Security

A large proportion of the cultivated land in China has been used for non-grain production purposes. As food insecurity is worsening worldwide, this issue has attracted attention from the Chinese government. In order to curb this trend and to ensure food security, this paper explores the quantitative characteristics and spatial distribution of cultivated land used for non-grain purposes in Liyang City, Jiangsu Province, and discusses the clustering characteristics and mechanisms behind this based on spatial autocorrelation analysis and geographically weighted regression (GWR). The results show that most of the cultivated land in Liyang City has not been used for non-grain purposes, and the cultivated land reserve is abundant. Among all land types, irrigable land has the largest non-grain production rate of cultivated land. There is no significant spatial correlation of cultivated land for non-grain purposes in most towns in Liyang, among which Kunlun Street is in the High-High (HH) zone and Daibu Town in the Low-High (LH) zone. It is also found that the same factor has various impacts on the non-grain production of cultivated land in different towns, and the number of enterprises is the core factor that leads to the non-grain use of cultivated land in Liyang city. Low food prices lead some farmers to plant other crops with higher economic benefits, and also lead to the outflow of the rural labor force. This will not only accelerate the non-grain production of cultivated land, but also cause a large amount of cultivated land to be in a state of unmanned cultivation, further aggravating the proportion of non-grain production in cultivated land.