Evaluation of Various DEMs for Quantifying Soil Erosion Under Changing Land Use and Land Cover in the Himalaya

Soil erosion is one of the serious environmental threats in the Himalayas, primarily exacerbated by the steep slopes, active tectonics, deforestation, and land system changes. The Revised Universal Soil Loss Equation was employed to quantify soil erosion from the Vishav watershed in the Kashmir Himalaya, India. Topography and land use/land cover (LULC) are important driving factors for soil erosion. Most often, a Digital Elevation Model (DEM) is used in erosion models without any evaluation and testing which sometimes leads to erroneous estimates of soil erosion. For the best topographic characterization of the watershed, four publicly available DEMs with almost identical resolution (∼30 m), were evaluated. The DEMs were compared with GPS measurements to determine the most reliable among the tested DEMs for soil erosion estimation. Statistical evaluation of the DEMs with GPS data indicated that the CARTO DEM is better with root mean square error (RMSE) of 18.2 m than the other three tested DEMs viz., Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), Shuttle Radar Topography Mission (SRTM), and Advanced Land Observing Satellite (ALOS). Slope length and slope steepness factors were computed from the DEMs. Crop cover and management factors were generated from the satellite-derived LULC. Moreover, rainfall data of the nearest stations were used to compute rainfall erosivity and soil erodibility factor was derived from the soil texture data generated from 375 soil samples. The simulated erosion estimates from SRTM, ALOS, and CARTO DEMs showed similar spatial patterns contrary to the ASTER estimates which showed somewhat different patterns and magnitude. The mean erosion in the study area has almost doubled from 2.3 × 106 tons in 1981 to 4.6 × 106 tons in 2019 mainly driven by the anthropogenic LULC changes. The increased soil erosion is due to the degradation of forest cover, urbanization, steep slopes, and land system changes observed during the period. In absence of the observations, the simulated soil erosion was validated with the land degradation map of the watershed which showed a good correspondence. It is hoped that the results from this work would inform policymaking on soil and water conservation measures in the data-scarce mountainous Kashmir Himalaya.

Land Tenure and Cotton Farmers’ Land Improvement: Evidence from State-Owned Farms in Xinjiang, China

The land system of state-owned farms in China is different from that in rural areas. Whether the land tenure of state-owned farms can play a role in protecting cultivated land is an important issue for the high-quality development of state-owned agriculture in China. This article develops a dynamic model to examine how land tenure influences farmers’ decisions on land improvement. It then analyzes this relationship based on cotton farmers’ household-level data from state-owned farms of Xinjiang in China. We applied methods that take into account the possible endogeneity of the land tenure. The results reveal that the stability of land tenure in the past will not affect the current behavior of farmers for they have a relatively stable expectation of current land tenure and a high degree of trust in the government and its policies. The intergenerational transfer of land tenure is not the key factor that affects farmers’ land conservation, and the relatively long-term duration of land tenure (possibly five years or more) during their careers is more important. Our findings also reveal that non-property factors, such as government intervention (e.g., technology promotion) that alleviates the limited rationality of farmers, cannot be ignored because they played a crucial role in past land improvement when land tenure was less stable.

Spatio-Temporal Pattern and Influence Mechanism of Cultivated Land System Resilience: Case from China

The study of cultivated land systems from the perspective of resilience is of great significance for the innovation of the research paradigm of cultivated land use and the rational utilization and protection of cultivated land. This study aims to explain the theoretical connotations of cultivated land system resilience (CLSR), construct an evaluation system and zoning rules for CLSR, and take 30 provinces of China as case study areas to explore the influencing factors of CLSR, so as to provide a reliable governance plan for the sustainable development of cultivated land. The results show that: (1) CLSR refers to a sustainable development ability that CLS—by adjusting the structure and scale of internal elements—absorbs and adapts to internal and external disturbances and shocks to the maximum possible extent, abandons the original inapplicable state, creates a new recovery path, achieves a new balance, and avoids system recession. (2) The overall CLSR of the 30 provinces showed an upward trend, and the degree of polarization of the distribution pattern was gradually intensified and experienced a transition process from “leading by resource and ecological resilience—equilibrium of each resilience—leading by production and scale structural resilience”. (3) In the north, east, and south coastal areas of China, CLSR mainly consists of the major evolution areas and the stable development areas; the potential excitation areas of CLSR are mainly concentrated in the central and western regions of China; the CLSR-sensitive lag areas and degraded vulnerable areas are mainly distributed in the northwest and southwest of China. (4) Water resource endowment has a strong influence on CLSR, while social economy mainly influences CLSR through ‘economic foundation-superstructures’ and ‘economic development-factor agglomeration’. (5) According to the different CLSR zones, CLSR was strengthened mainly from the aspects of driving factor agglomeration, building factor free-flow systems, and multi-means support.

UniFHy v0.1: A community framework for the terrestrial water cycle in Python

Land surface, hydrological, and groundwater modelling communities all have expertise in simulating the hydrological processes at play in the land system, but these communities have largely remained distinct with limited collaboration between disciplines. In order to address key societal questions regarding the future availability of water resources and the intensity of extreme events such as floods and droughts in a changing climate, these communities must build on the strengths of one another. The development of a common modelling infrastructure, a framework, can contribute to stimulating cross-fertilisation between them. By allowing (parts of) their existing models to be coupled together, improved land system models can be built to better understand and simulate the terrestrial hydrological cycle. This paper presents a Python implementation of such a framework named the Unified Framework for Hydrology (unifhy). The framework aims to provide the technical infrastructure required to couple models, taking into account the specific needs of a land system model. Its conceptual design and technical capabilities are outlined first, before its usage and useful characteristics are demonstrated through case studies. The limitations of the current framework and necessary future developments are finally presented as a road map for later versions and/or other implementations of the framework.

Quantifying Earth system interactions for sustainable food production: an expert elicitation

Several safe boundaries of critical Earth system processes have already been crossed by human perturbations. Recent research indicates that not accounting for the interactions between these processes may further narrow the safe operating space for humanity. Yet existing work accounts only for transgression of single boundaries and only a few studies take some of the boundary interactions into account. For future sustainability assessments, it is essential to understand boundary transgressions and their interactions more comprehensively. Here, we explore quantitatively how strongly seven variables, representing Earth system processes relevant to food production, interact with each other, using a structured expert knowledge elicitation. We identify Green water and Land system change as crucial interactive processes through their impacts on multiple relevant processes, while Biosphere integrity-land, freshwater and ocean components appear to be most affected by other Earth system processes, most notably Blue water and Biogeochemical flows. The elicitation also enabled us to map the complex network of mechanisms mediating interactions, to support integrated Earth system and planetary boundaries modelling and assessments. Finally, we created a prioritisation scheme for future research according to the interaction strengths and existing knowledge gaps. Our analysis improves our understanding of Earth system interactions, with clear implications for sustainable use of natural resources such as the biophysical limits for food production.

Institutional Diversity of Transferring Land Development Rights in China—Cases from Zhejiang, Hubei, and Sichuan

With the continuous urbanization, China is facing a dilemma of achieving two conflicting targets in land governance, i.e., the continuous supply of urban construction land to support urbanization and the preservation of cultivated land for food security. Under China’s dual land system, the implementation of the “Linkage between Urban-land Taking and Rural-land Giving” (Linkage) policy is of great significance in promoting more inclusive urbanization by commodifying the land development right and connecting urban and rural land markets. In the specific land property right system and changing land governance of China, this policy appears to provide an opportunity for stakeholders other than the state to compete for the value from the transfer of development rights (TDR) and triggers the emergence of diversified approaches in organizing land projects in rural China. Based on the theoretical perspective of New Institutional Economics and empirical evidence from Zhejiang Province, Hubei Province, and Sichuan Province, this paper conducts a comparative institutional analysis for China’s TDR practice and argues that the diversified operational approaches in China’s practice have aligned various interests of the stakeholders through flexible participation methods and elaborate reallocation of land property rights, in order to fit various institutional environments and material conditions

CONSEQUENCES OF LAND REFORM IN UKRAINE ON THE EXAMPLE OF GEORGIA AND MOLDOVA

The article is aimed at investigating the expediency of land reform in Ukraine. The process and consequences of land reforms in Georgia and Moldova are considered. The indicators of development of the agricultural sector and the degree of involvement of the population in it are revealed. The world experience of land distribution was analysed. The most effective strategy of land reform development by analysing the research in the dependence of efficiency of land plots utilization on the size of households that cultivate them was revealed. The efficiency of agroholdings and family farms is compared. Determined trends in the distribution and size of plots in developed countries. Analysed the gradual adoption of decisions in the development of land reform and their effects on the success of such reform in Georgia and Moldova. The current decisions of the Ukrainian government on the way to reforming land distribution and use of land resources are considered. Parallels of the current Ukrainian land reform based on the experience of Moldova and Georgia are identified. The assumption of success and expediency of the decisions taken, which could potentially come into force when the Verkhovna Rada of Ukraine discusses the format of the land reform, was put forward. Analysed the further development of the land sector according to the gradual entry into force of the adopted legislation. The issues of expediency of opening the land market to foreigners were considered. Penetrated the experience of international partners and countries already decided on the admission or non-admission of foreign contractors to the national land market. The degree of development of accounting and inventory of existing land plots and completeness of filling the land cadastre of the three countries under study was determined. The research method was the analysis of the current land system of Georgia and Moldova by studying articles on the dynamics of changes in local legislation. The main economic indicators that may indicate the degree of success of the reforms in these countries are considered. Due to such indicators, a detailed analysis of the latest changes in the legislation of Ukraine predicted and assessed the feasibility of the reforms.

An Integrated CNN Model for Reconstructing and Predicting Land Use/Cover Change: A Case Study of the Baicheng Area, Northeast China

Land use and land cover change (LUCC) modeling has continuously been a major research theme in the field of land system science, which interprets the causes and consequences of land use dynamics. In particular, models that can obtain long-term land use data with high precision are of great value in research on global environmental change and climate impact, as land use data are important model input parameters for evaluating the effect of human activity on nature. However, the accuracy of existing reconstruction and prediction models is inadequate. In this context, this study proposes an integrated convolutional neural network (CNN) LUCC reconstruction and prediction model (CLRPM), which meets the demand for fine-scale LUCC reconstruction and prediction. This model applies the deep learning method, which far exceeds the performance of traditional machine learning methods, and uses CNN to extract spatial features and provide greater proximity information. Taking Baicheng city in Northeast China as an example, we verify that CLRPM achieved high-precision annual LUCC reconstruction and prediction, with an overall accuracy rate 9.38% higher than that of the existing models. Additionally, the error rate was reduced by 49.5%. Moreover, this model can perform multilevel LUCC classification category reconstructions and predictions. This study casts light on LUCC models within the high-precision and fine-grained LUCC categories, which will aid LUCC analyses and help decision-makers better understand complex land-use systems and develop better land management strategies.

The Politics of Land Law: Poverty and Land Legislation in Bangladesh

<p>This thesis examines the major colonial and post-colonial land laws of Bangladesh and their relationship with poverty. It interprets them in the light of historical developments and social realities. The thesis argues that land laws in Bangladesh are essentially anti-poor. They contribute to the perpetuation of poverty. At present, two-thirds of the poor in Bangladesh are land-related poor. The land system that prevailed in colonial Bengal during the British period deprived the peasants of their land rights. This situation demanded a radical land reform based on a distributive approach upon decolonisation in 1947. Unfortunately, in the post-colonial political and legal settings of Bangladesh, land distribution has been unequal. Such inequality coupled with a weak land tenure system and fragile institutional reform created widespread poverty. The Bangladeshi land laws are complex and vague and dominated by politics. Its land law regime has structural loopholes and ideological drawbacks, which are enough to make reform attempts dysfunctional. Poverty in Bangladesh is a result of cumulative and mutually reinforcing deprivations. Land law is a major participant in it. Poverty will persist unless law addresses the true reasons of the poverty and a pro-poor approach to land reform is pursued. The gap between “law” and “land” is exposed and a distributive land law reform model is proposed.</p>