scholarly journals Synthesis of agricultural land system change in China over the past 40 years

2018 ◽  
Vol 13 (5) ◽  
pp. 473-479 ◽  
Author(s):  
Zhanli Sun ◽  
Liangzhi You ◽  
Daniel Müller
2020 ◽  
pp. 37-43
Author(s):  
B.I. KORZHENEVSKIY ◽  
◽  
N.V. KOLOMIYTSEV ◽  
G.YU. TOLKACHEV

Putting out of using large areas of agricultural lands in the central region over the past years has led to worsening the prospects of their purposed use, although the problem of the relevance of their restoration still remains. For many years the unused land was exposed to both natural exogenous processes such as erosion, suffusion, etc. and biological and chemical changes, usually for the worse for agriculture. There are considered elements of monitoring aimed at assessing the prospects or lack of perspectives of rehabilitation of degraded lands. An energy approach to assessing the state of slopes and soils located within these slopes is presented. The main factors of natural and anthropogenic character in assessing the prospects for land restoration are their steepness, excess relative to local bases of erosion other morphological characteristics of slopes which in general is reduced to an assessment of the energy provision of slopes and soils. So the higher the energy capacity of slopes – they are less promising for development, for soils – there is a reverse picture – the higher their energy reserves, the more promising is their use. Approaches to zoning the territory for monitoring from larger taxons of natural and anthropogenic genesis to the sites of special surveillance within which the prospects for rehabilitation of the agricultural land are evaluated. The most important factor is the material expediency of such actions, i.e. before starting the restoration work it is necessary to assess the profitability or loss of the proposed event. In cases of the material expediency it is feasible as further actions to include energy assessments of slopes and soils; zoning of the object according to the steepness and oriented characteristics of soil washout; and the possibility of obtaining agronomic and meteorological data on a timely basis. The result of the work is a forecast assessment of the prospects for restoring degraded land for the intended purpose using modern databases and WEB-systems.


Atmosphere ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 281
Author(s):  
Stuart L. Joy ◽  
José L. Chávez

Eddy covariance (EC) systems are being used to measure sensible heat (H) and latent heat (LE) fluxes in order to determine crop water use or evapotranspiration (ET). The reliability of EC measurements depends on meeting certain meteorological assumptions; the most important of such are horizontal homogeneity, stationarity, and non-advective conditions. Over heterogeneous surfaces, the spatial context of the measurement must be known in order to properly interpret the magnitude of the heat flux measurement results. Over the past decades, there has been a proliferation of ‘heat flux source area’ (i.e., footprint) modeling studies, but only a few have explored the accuracy of the models over heterogeneous agricultural land. A composite ET estimate was created by using the estimated footprint weights for an EC system in the upwind corner of four fields and separate ET estimates from each of these fields. Three analytical footprint models were evaluated by comparing the composite ET to the measured ET. All three models performed consistently well, with an average mean bias error (MBE) of about −0.03 mm h−1 (−4.4%) and root mean square error (RMSE) of 0.09 mm h−1 (10.9%). The same three footprint models were then used to adjust the EC-measured ET to account for the fraction of the footprint that extended beyond the field of interest. The effectiveness of the footprint adjustment was determined by comparing the adjusted ET estimates with the lysimetric ET measurements from within the same field. This correction decreased the absolute hourly ET MBE by 8%, and the RMSE by 1%.


2021 ◽  
Vol 126 ◽  
pp. 102380
Author(s):  
Marc Schmid ◽  
Andreas Heinimann ◽  
Julie G. Zaehringer

Author(s):  
Gennadiy A. Polunin ◽  

The article is devoted to substantiating the prospects for increasing the marginal volumes of agricultural production for export in the next four years. Two scenarios of such production are considered: 1) expansion and 2) intensification of the use of land resources. As part of the development of the first scenario, an analysis of the distribution of unused agricultural land, including arable land, by federal districts was carried out. Also, based on the forecast of the introduction of additional annual volumes of acreage in the subjects of the Federation, the calculation of additional volumes of agricultural production, which can be expected in the next four years, was carried out. The analysis of data on the increase in the yield of export-oriented crops over the past five years has been carried out, in the framework of the second scenario, the calculation of the projected additional yield due to the intensification of agriculture is presented. The results of the study indicate that the intensification of agriculture will have the greatest impact on the growth of production and export of agricultural products in the near future.


2020 ◽  
pp. 5-20
Author(s):  
G. A. Polunin ◽  
V V. Alakoz

The results of scientifi c research on the state of agricultural land use in the subjects of the Russian Federation included in the Non-Chernozem Economic Zone of the European part of the country are considered in this article. The paper consists of data on distribution of currently unused arable land; the area of land plots in common shared ownership, the boundaries of which are not available in the Real Estate Cadastre; information about especially valuable productive agricultural land; economic prerequisites for the use of land by agricultural producers on the basis of lease or ownership, as well as changes over the past fi ve years in sown areas, the productivity of arable land in farms of all categories, data on the level of profi tability of agricultural organizations, unprofi table agricultural organizations etc.


2019 ◽  
Vol 11 (3) ◽  
pp. 471-488 ◽  
Author(s):  
Liu Shouying

Purpose The purpose of this paper is to analyze the structure and changes of China’s land system. To achieve this aim, the paper is divided into four parts. The first part gives a brief introduction to the structural characteristics of the Chinese land institutional arrangements; the second part analyzes the reform process of the land system in the past 40 years and its path of change; the third part engages the discussion about the historic contribution made by the land institutional change to rapid economic growth and structural changes; and the final part is conclusion and some policy implications. Design/methodology/approach After 40 years of reforms and opening up, China has not only created a growth miracle unparalleled for any major country in human history, but also transformed itself from a rural to an urban society. Behind this great transformation is a systemic reform in land institutions. Rural land institutions went from collectively owned to household responsibility system, thereby protecting farmers’ land rights. This process resulted in long-term sustainable growth in China’s agriculture, a massive rural-urban migration and a historical agricultural transformation. The conversion of agricultural land to non-agricultural uses and the introduction of market mechanisms made land a policy tool in driving high economic growth, industrialization and urbanization. Findings Research shows that the role of land and its relationship with the economy will inevitably change as China’s economy enters a new stage of medium-to-high speed growth. With economic restructuring, low-cost industrial land will be less effective. Urbanization is also shifting from rapid expansion to endogenous growth so that returns on land capitalization will decrease and risks will increase. Therefore, China must abandon land-dependent growth model through deepening land reforms and adapt a new pattern of economic development. Originality/value This paper gives a brief introduction to the structural characteristics of the Chinese land institutional arrangements, analyzes the reform process of the land system in the past 40 years and its path of change, and evaluates the historic contribution made by the land institutional change to rapid economic growth and structural changes.


Clay Minerals ◽  
2009 ◽  
Vol 44 (2) ◽  
pp. 161-176 ◽  
Author(s):  
M. Calabi Floody ◽  
B. K. G. Theng ◽  
P. Reyes ◽  
M. L. Mora

AbstractBecause of their large potential for agricultural, industrial and medicinal applications, nanomaterials have been the focus of much research during the past few decades. Nanoclays are natural nanomaterials that occur in the clay fraction of soil, among which montmorillonite and allophane are the most important species. Montmorillonite is a crystalline hydrous phyllosilicate (layer silicate). Organically-modified montmorillonites or ‘organoclays’, formed by intercalation of quaternary ammonium cations, have long been used as rheological modifiers and additives in paints, inks, greases and cosmetics and as carriers and delivery systems for the controlled release of drugs. Perhaps the largest single usage of organoclays over recent years has been in the manufacture of polymer-clay nanocomposites. These organic–inorganic hybrid materials show superior mechanical, thermal and gas-barrier properties. Organoclays are also useful in pollution control and water treatment. Allophane is a non-crystalline aluminosilicate derived from the weathering of volcanic ash. A large proportion of the agricultural land in Chile is covered by volcanic soils,the clay fraction of which is dominated by allophane. Consisting of nanosize (3.5–5.0 nm) hollow spherules, allophane is a suitable support material for enzyme immobilization. Allophane is also effective at adsorbing phenolic compounds and colour from kraft mill effluents and phosphate from water and wastewater.


2018 ◽  
Vol 19 (1) ◽  
pp. 73-88
Author(s):  
Rihlah Nur Aulia ◽  
Izzatul Mardhiah ◽  
Dian Bagus ◽  
Ade Gunawan ◽  
Dian Elvira Nanda Sari

This research is backgrounded by some environmental problems which increasingly worries day plus the problem of management of natural resources that are not friendly and tend to be greedy. The rapid pace of development and population growth in the past decade has led to the conversion of forest and agricultural land into industrial, plantation and residential areas, resulting in degradation of uncontrolled environmental damage and pollution. The main purpose of this research is to know how environmental management conducted by Pondok Pesantren SPMAA Lamongan, East Java. In addition, the purpose of this study to find out how the implementation of environmental management conducted by the boarding school as a mirror of concern for the surrounding environment. This research uses qualitative approach. This means that the data collected is not a number, but the data comes from interviews, personal documents, memo notes, field notes, and other official documents. So that the purpose of this study is to describe the empiric reality behind the phenomenon in depth, detailed, and thorough. This research concludes that every pesantren has its own characteristic in running the concept of ekopesantren that exist, and in this pesantrenen pesantren SPMAA ekopesantren understood as pesantren that can coexist with nature and full of lesson will utilize resources wisely and wisely. Although this boarding school has not fully implemented ekopesantren. This is seen from ecopesantren indicator that has been fulfilled and that has not been fulfilled.      


1975 ◽  
Vol 7 (1) ◽  
pp. 131-136
Author(s):  
H. Evan Drummond

Property tax systems have undergone rapid change in almost every state during the past few years. Consequently, their distributional impact merits investigation. The incidence of the property tax is at the heart of the distributional question. It is generally felt that land owners bear the full burden of property taxes and that changes in it are capitalized into property values. Usually it is assumed that property taxes are not shifted forward to the consumer, but there has been little empirical verification of this notion. This paper will develop a simple model of the land market to test several alternative hypotheses concerning the incidence of property taxes on agricultural land in the United States.


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