Uncultivated Land Research Articles

Impact of Land Use Conversion on Soil Structure and Hydropedological Functions in an Arid Region

ABSTRACTLand use conversion critically affects soil structure and associated functions. This study investigated variations in soil structure and hydropedological characteristics across different land use types, that is, uncultivated, cultivated, and abandoned land under an arid condition. Water‐stable aggregates in the uncultivated land were 15.4%–37.1% of those in the cultivated and abandoned lands at depths of 0–60 cm. Reclamation of the uncultivated land enhanced soil aggregate stability, while prolonged tillage led to the loss of binding organic matter, breakdown of large aggregates and decrease in aggregate stability. The mean weight diameter of aggregates at 0–40 cm depth in the cultivated land was 39.0% lower than in the abandoned land. The volume fraction of micropores (< 100 μm) in the cultivated soils was 3.7%–39.7% of that in the uncultivated soils, whereas macropores (> 1000 μm) was 1.4–1.8 times greater. Following the abandonment, soil pore diversity recovered and a hierarchical structure developed. In the abandoned land, the volume fraction of micropores (< 100 μm) was 2.4–18.9 times that of the cultivated lands, while macropores (> 1000 μm) constituted 81.4%–93.9% of those in the cultivated lands. The permeability and longitudinal dispersivity of soils in the cultivated land were significantly lower than in the uncultivated and abandoned lands, particularly at deeper soil layers. The increase in large pores in the abandoned land, important for water movement and solute transport, resulted in an order‐of‐magnitude rise in both permeability and longitudinal dispersivity compared with the cultivated lands. Overall, the abandoned land showed potential for rehabilitation from the perspectives of soil aggregates and pore structure. The findings may provide reference for land reclamation and management in arid regions.

Changes in the population and diversity of plant parasitic nematodes and their effects on sugarcane growth at Wonji‐Shoa Sugar Estate, Ethiopia

AbstractIn Wonji‐Shoa Sugar Estate (WSSE), sugarcane (Saccharum spp. hybrid) yields have declined by about 48% over the last 70 years. One of the causes for the decline is assumed to be the long‐term monoculture production system that results in the buildup of plant parasitic nematodes (PPNs). Therefore, the population and diversity of PPNs were investigated by conducting soil sampling using a biosequential method (simultaneous sampling of the soils of adjacent cultivated land [CL] and uncultivated land [UL]) and a chronosequential method (taking soil samples at different times from the same site). The samples were subjected to analysis using standard procedures to determine the change in the population, and identify the genera of PPNs. Additionally, a pot experiment that involved fumigation was conducted on top soils sampled from the CL and UL of the plantation. The results revealed that about 10 genera of PPNs (Meloidogyne, Helicotylenchus, Hoplolaimus, Rotylenchulus, Hemicycliophora, Discriconemella, Xhiphinema, Pratylenchus, Tylenchorhynchus, and Scutellonema) were detected, of which the first four were newly identified. The population density and the number of genera of PPNs found in the CL were 36‐fold and 4.5‐fold higher than those found in the UL, respectively. Furthermore, fumigation reduced the population of the PPNs by 61% and increased production of cane biomass by 63%. It is concluded that the soils of the WSSE are infested by PPNs, which consequently have detrimental effects on sugarcane growth. While amending soil fertility is crucial, reversing the decline in sugarcane yields also necessitates implementing an integrated soil management system that includes PPNs.

Effects of Agricultural Land Use on Desert Soil Classification in Holy Karbala Governorate

This study was conducted to evaluate physical, chemical, and morphological features to classify soils at the subgroup level. The research area, located west of Karbala, consists of three locations, each comprising pedons in both cultivated and uncultivated lands. GPS coordinates were recorded, and morphological descriptions of pedon horizons were made in accordance with the American Soil Survey Manual. This study investigates the effect of agricultural land use on the classification of desert soils in the Holy Karbala Governorate. The results revealed that the dry climate caused diversity in the morphological features of the soils, mainly in horizon type, thickness, and arrangement. Agricultural usage had an impact on diagnostic horizons, particularly the gypsic horizon, and features such as soil color, structure, organic matter, carbonate minerals, gypsum, and root distribution. However, there was no substantial impact on soil texture development, and soils did not show a consistent pattern of soil separation distribution with depth, indicating weak pedogenic processes. The most common texture classes were loamy sand, sandy loam, and sand, with sand contents ranged from 902.08 to 574.12 g kg. Soil bulk density differed from 1.67 to 1.30 Mg m³, with lower values in farmed areas. Chemical properties were influenced, with soil pH ranging from 8.36 to 7.54, electrical conductivity (EC) from 5.46 to 2.03 dS m, cation exchange capacity (CEC) from 15.25 to 2.05 meq.100g, organic matter from 43.51 to 1.18 g kg, carbonate minerals from 461.18 to 174.06 g kg, and calcium sulfate from 182 to 21 g kg. The soils were classed as Aridisols because they were found in a dry desert with an Aridic moisture regime. The presence of distinctive saline layers such as Calcic and Gypsic was discovered, resulting in the classification of cultivated soils as Typic Haplocalcids and uncultivated lands as Typic Calcigypsids.

Land use patterns influence in the soil microbial composition

Studies on the impact of land-use patterns on soil health and sustainability have indicated that land-use changes and unsuitable agricultural practices are key driving factors in the degradation of soil. However, the impact of land-use patterns on soil microbial diversity is not entirely consistent or known, and the specific effects of environmental factors need to be further considered. This study explored the impact of three different land-use patterns—rotation land (RL), garden land (GL), and uncultivated land (UL)—on soil health in a farming region by analyzing the soil physicochemical properties and the diversity of the soil bacterial and fungal communities. In this study, the results showed that the soil pH of GL was significantly lower than that of RL and UL, total nitrogen was lowest in GL, and available potassium and soil organic carbon were higher in RL and GL than in UL. The impact of the land-use patterns on microbial diversity was somewhat inconsistent, but greater on soil bacteria than fungi, with 17 bacterial and 4 fungal metabolic pathways showing significant differences. In particular, a decrease in the relative abundance of dominant bacteria was observed in GL. The land-use patterns had little impact on fungal functional genes; however, plant pathogen-related fungi were significantly higher in GL than in RL and UL. Overall, these results indicate that while the soil basic nutrients in different land-use patterns were high, long-term single planting (GL) still had a negative impact on the health and sustainability of the soil, especially owing to low soil pH. Therefore, when evaluating the effect of different planting systems on soil health, it is necessary to consider the true effect of local agricultural measures on soil properties and microbial community composition, and monitor for microbial diseases in the field to determine the impact of land-use patterns on crop production.

Investment of Waqf funds in Malaysia: A Descriptive Study of Cultivating Uncultivated Land from Public Interest Perspective

Investment of Waqf funds in Malaysia: A Descriptive Study of Cultivating Uncultivated Land from Public Interest Perspective

Transformation of Agriculture in Damoh District of Madhya Pradesh

India has been considered as a land of villages and from very beginning agriculture has been main means of livelihood of the residents of the country specially people living in rural areas. Agriculture plays a vital role in the nation's economy. About two third of the working population earn their living through agriculture and agriculture sector contributes about 26 per cent in the gross domestic production of the country. The present study examines the transformation of the various dimension of the agriculture in the Damoh district of Madhya Pradesh based on secondary data. With the growing pressure of population, demand for land for non-agricultural activities, implementations of rural development programmes and activities, the land use pattern, cropping pattern, irrigational facilities, farming techniques and other allied activities in the study area has transformed during the period 1990 to 2020. Damoh district is located in the Bundelkhand region of Madhya Pradesh and is part of Sagar division. Total geographical area of the district is 7306 sq.km. out of which 323386 hectares land is available for cultivation with 293599 hectares of irrigated land. The proportion of forest and fallow land has decreased in last two decades while the proportion of net shown area, other uncultivated land, land not available for agriculture and double cropped area has increased during the period. The cropping pattern of the study region, also transformed. The use of modern agricultural implements, fertilizers and pesticides too has increased during 1990-2020.

Measurement and analysis of regional water-energy-food nexus resilience with an improved hybrid kernel extreme learning machine model based on a dung beetle optimization algorithm

CONTEXTIn traditional water-energy-food nexus (WEFN) system analysis, the impact of resilience is insufficiently considered, and the accuracy of resilience assessment is low, which can easily lead to system imbalance. Modeling measures can yield optimal evaluation results and provide decision makers with a scientific and efficient basis for management. OBJECTIVEThe objective of this study was to provide a new research paradigm for exploring the sustainable development of WEFN systems by quantitatively and accurately assessing WEFN resilience and identifying its key driving factors. METHODSThe connotation of WEFN resilience was established, and a human-centered conceptual framework for WEFN resilience was constructed. A WEFN resilience evaluation system was scientifically and completely constructed using qualitative and quantitative index screening methods. The hybrid kernel extreme learning machine (HKELM) model was improved based on the dung beetle optimization (DBO) algorithm to measure and analyze the WEFN resilience of the China Beidahuang Group. The CRiteria Importance Through Intercriteria Correlation (CRITIC) method was adopted to calculate the evaluation index weight of the WEFN system of the Beidahuang Group. Model performance verification methods, such as application of the theory of serial number summation, were used to evaluate the performance of the DBO-HKELM model. RESULTS AND CONCLUSIONSThe results showed that over time, the Beidahuang Group's WEFN resilience exhibited a fluctuating upward trend. From 2006 to 2008, WEFN resilience declined to level II because of predatory agricultural production and management practices. From 2008 to 2018, the WEFN resilience increased to level IV due to the protection of uncultivated land, the optimization of irrigation methods, and the increasing maturity of the agricultural modernization development model. Likewise, from 2018 to 2020, the WEFN resilience stabilized at level IV because of the optimization of agricultural planting structures and the reduction in coal consumption. Spatially, the WEFN resilience of various branches of the Beidahuang Group exhibited a trend of “gradually decreasing from north to south.” Differences in certain variables, such as the proportion of area irrigated with electromechanical wells, were the most important factors related to changes in WEFN resilience over time. The DBO-HKELM model has notable advantages over the FA-HKELM and NGO-HKELM models in terms of fitting accuracy, optimization rate, reliability, rationality, and robustness. SIGNIFICANCEThese research results could enrich quantitative assessment methods for determining WEFN system recovery strength and provide scientific support for the safe operation and sustainable development of agricultural economies and societies.

Long-Term Effects of Different Tillage Systems and Their Impact on Soil Properties and Crop Yields

The scientific aim of this article is to elucidate the effects of various tillage practices on soil properties and crop yields; additionally, it seeks to highlight the significant potential of specific farming systems in enhancing soil organic carbon, thereby positively influencing CO2 emissions from soil. In the experimental station of Vytautas Magnus University, Kaunas District, Lithuania (54°52′50″ N and 23°49′41″ E), a long-term field experiment has been established since 1999, and studies have been conducted since 2003. The soil of the experimental site is classified as Epieutric Endocalcaric Planosol (Endoclayic, Episiltic, Aric, Drainic, Endoraptic, Uterquic), according to the World Reference Base (WRB, 2022). Two primary factors were assessed. Factor A incorporated practices of straw removal versus straw chopping and spreading, while Factor B evaluated a spectrum of tillage techniques: conventional deep plowing and two no-tillage practices, one of which involved cover crops. The findings from this long-term study highlight a significant increase in SOC stocks across all treatments over the 20-year period. Notably, the no-tillage practices, coupled with the spreading of chopped straw, demonstrated the most substantial growth in SOC levels, particularly in the top 0–10 cm soil layer. This trend underscores the effectiveness of minimizing soil disturbance and incorporating organic matter in boosting SOC stocks. The different tillage systems influence CO2 emissions from soil. Initially, direct sowing into uncultivated land, both with and without cover crops, led to a notable reduction in CO2 emissions compared to conventional plowing. However, this effect was found to vary over the growth cycle of the plant, highlighting the dynamic interaction between tillage practices, soil properties, and environmental conditions. Collaborative research efforts that involve farmers, scientists, policymakers, and other stakeholders are crucial for the development of holistic, practical, scalable solutions that enhance the sustainability and productivity of agricultural systems. This study contributes to the growing body of knowledge on sustainable agriculture, providing insights for farmers, agronomists, and policymakers in their quest to promote environmentally sound and productive agricultural systems.

The social integration of rural migrants in urban China: The effect of hometown land tenure

AbstractWhile rural migrants living in different housing tenures present significantly variegated levels of social integration, little is known about how land tenure in their place of origin affects their integration into the host cities. Using the 2017 China Migrants Dynamic Survey, we identified three dimensions of social integration: (1) permanent settlement intention, (2) cultural integration and (3) psychological integration. We find that migrants do not feel psychological isolation; their settlement intention is lower as a more realistic judgement of prospects. Their cultural integration is even lower, indicating it is a long‐term process. Migrants with land farming by relatives and friends and land subleasing to private are more socially integrated, while hiring someone to cultivate the land, leaving land uncultivated and other land disposal methods reduces migrants' social integration. Furthermore, land subleasing led to stronger psychological integration, even after controlling for the potential endogeneity issue. It weakens their attachment to their hometowns and increases their income to achieve stronger integration. The effect is more salient in the migrants of the new generation, in second‐tier cities and in the digital economy sector.

Impacts of Organic and Non-Organic Cultivation Practices on Soil Fertility Parameters of Selected Paddy Lands Based on the Duration of Cultivation in Wet and Intermediate Climate Zones of Sri Lanka

Sri Lanka has been practicing the cultivation of rice as its main staple food in two major agricultural techniques; organic and non-organic. The major aim of the present study was to analyze and compare the time duration-based impacts of the above two agricultural practices on paddy soil fertility indicators as the preliminary step of a long-term research project. Organic and non-organic paddy fields that have been cultivated for 2 seasons in Thorapitiya in the Matale district were selected as short-term cultivated lands. Land cultivated for 10 years organically in Homagama and land with a non-organic cultivation history of 20 years in Kottawa was selected as long-term cultivated lands. A total number of 35 samples were collected including the control samples from adjacent uncultivated land during the first phase of the Maha season 2021/2022. The samples were dried, sieved and then analyzed in their physical and chemical properties; color, texture, particle size distribution, pH, electrical conductivity (EC), organic carbon content (OCC), total nitrogen content (TNC), available phosphorus content (APC), exchangeable potassium content (EPC), and exchangeable magnesium content (EMC). The soil samples from Thorapitiya had a reddish-brown nature while most of the samples from Kottawa and Homagama had a grayish-brown color. Higher clay percentages were found in the soil samples from long-term organically cultivated lands in Homagama. The uniformity coefficient (Cu) values for soils from study areas except Homagama lie in the range for well-graded soil while the coefficient of gradation (Cc) values of all three areas were not in the above range. Short-term cultivation using organic and non-organic fertilizers did not show a significant difference in soil texture, pH, EC, APC, EPC, and EMC values. Most of their cultivated lands had a lower pH (~5.5–6.0) than the corresponding control plots (~5.8–6.4). The TNC levels in non-organically cultivated lands were significantly higher than in organic lands. Practicing agricultural activities for a prolonged period has resulted in significant differences in soil texture, pH, EC, OCC, TNC and APC between organic and non-organic lands. Higher OCC and lower pH, EC and APC values have been obtained for long-term organically cultivated lands than their non-organic counterparts. The TNC, APC and EPC levels were higher in most of the long- term organic and non-organic lands than in their control samples. Several amendments have to be made to bring the fertility parameters to an optimum level in long-term cultivated lands. 
 Keywords: Soil fertility, Paddy soil, Cultivation history, Organic cultivation, Non-organic cultivation

Bird species richness and diversity responses to land use change in the Lake Victoria Basin, Kenya

The increasing demand for cultivated lands driven by human population growth, escalating consumption and activities, combined with the vast area of uncultivated land, highlight the pressing need to better understand the biodiversity conservation implications of land use change in Sub-Saharan Africa. Land use change alters natural wildlife habitats with fundamental consequences for biodiversity. Consequently, species richness and diversity typically decline as land use changes from natural to disturbed. We assess how richness and diversity of avian species, grouped into feeding guilds, responded to land use changes, primarily expansion of settlements and cultivation at three sites in the Lake Victoria Basin in western Kenya, following tsetse control interventions. Each site consisted of a matched pair of spatially adjacent natural/semi-natural and settled/cultivated landscapes. Significant changes occurred in bird species richness and diversity in the disturbed relative to the natural landscape. Disturbed areas had fewer guilds and all guilds in disturbed areas also occurred in natural areas. Guilds had significantly more species in natural than in disturbed areas. The insectivore/granivore and insectivore/wax feeder guilds occurred only in natural areas. Whilst species diversity was far lower, a few species of estrildid finches were more common in the disturbed landscapes and were often observed on the scrubby edges of modified habitats. In contrast, the natural and less disturbed wooded areas had relatively fewer estrildid species and were completely devoid of several other species. In aggregate, land use changes significantly reduced bird species richness and diversity on the disturbed landscapes regardless of their breeding range size or foraging style (migratory or non-migratory) and posed greater risks to non-migratory species. Accordingly, land use planning should integrate conservation principles that preserve salient habitat qualities required by different bird species, such as adequate patch size and habitat connectivity, conserve viable bird populations and restore degraded habitats to alleviate adverse impacts of land use change on avian species richness and diversity.

The Influence of Intensive Agriculture on Soil Properties and Nutrient Availability in Kauwi and Zombe Wards of Kitui County, Kenya

Soils perform various functions for the purpose of supporting agroecosystems. Numerous agroecosystem support functions rely on the properties of soils. Inappropriate agricultural techniques and land usage have led to a global 12.5% drop in soil health during the previous few decades. Inappropriate cultivation, nutrient mining, and overuse of inorganic chemical treatments are some of the activities that may have degraded soil quality. A study on the influence of intensive agriculture on soil properties and nutrient availability under different cropping systems and locations was done in the years 2018 and 2019 in Kauwi and Zombe Wards of Kitui County, Kenya. Four commonly occurring cropping systems, namely, vegetable, cereal, fruit, and agroforestry, were selected in the two locations. Uncultivated land in the area was considered as control. In total, there were five treatments, which were replicated five times in each of the locations. During the typical long (March, April, May) and short (October, November, December) rainfall seasons, composite soil samples were randomly taken from the cropping systems. Analysis of the results revealed that the influence of cropping systems on locational variation of soil quality parameters varied significantly (p<0.05). Further, the interaction between cropping strategies and locations significantly influenced soil pH and soil organic carbon. In Zombe, the vegetable cropping system registered the lowest soil pH and electrical conductivity values. Similarly, Soil Organic Carbon, Nitrogen, Phosphorus, and Potassium mean values under the vegetable farming system were higher in Zombe compared to Kauwi ward, probably due to the heavy application of fertilisers. Based on the results from the study, farmers in the area should be sensitised to embrace sustainable agricultural practices that promote moderate application of fertilisers to maintain healthy soils

«Par plains ne par forez»: lineamenti del territorio forestale nei romanzi di Chrétien de Troyes

The vulgate idea of the medieval forest as uncultivated and remote land does not correspond to the reality of the documentation: since the early Middle Ages, in fact, the forest was part of the human consortium and was intensively exploited for its resources, also thanks to the systematic agricultural conversion of some of its portions. However, the image that emerges from the works of courtly narrative is decidedly the opposite and is rather influenced by the cultural heritage responsible for the literary portrayal as a disturbing place, in which supernatural forces stir. This image, certainly preponderant and thus privileged in studies, has overshadowed the observation of the actual features of the wilderness in the authors of the Western Middle Ages. In this essay, an attempt is made to detect traces of the real woodland landscape in the novels of Chrétien de Troyes.

The Influence of Intensive Agriculture on Soil Properties and Nutrient Availability in Kauwi and Zombe Wards of Kitui County, Kenya

Soils perform various functions for the purpose of supporting agroecosystems. Numerous agroecosystem support functions rely on the properties of soils. Inappropriate agricultural techniques and land usage have led to a global 12.5% drop in soil health during the previous few decades. Inappropriate cultivation, nutrient mining, and overuse of inorganic chemical treatments are some of the activities that may have degraded soil quality. A study on the influence of intensive agriculture on soil properties and nutrient availability under different cropping systems and locations was done in the years 2018 and 2019 in Kauwi and Zombe Wards of Kitui County, Kenya. Four commonly occurring cropping systems, namely, vegetable, cereal, fruit, and agroforestry, were selected in the two locations. Uncultivated land in the area was considered as control. In total, there were five treatments, which were replicated five times in each of the locations. During the typical long (March, April, May) and short (October, November, December) rainfall seasons, composite soil samples were randomly taken from the cropping systems. Analysis of the results revealed that the influence of cropping systems on locational variation of soil quality parameters varied significantly (p<0.05). Further, the interaction between cropping strategies and locations significantly influenced soil pH and soil organic carbon. In Zombe, the vegetable cropping system registered the lowest soil pH and electrical conductivity values. Similarly, Soil Organic Carbon, Nitrogen, Phosphorus, and Potassium mean values under the vegetable farming system were higher in Zombe compared to Kauwi ward, probably due to the heavy application of fertilisers. Based on the results from the study, farmers in the area should be sensitised to embrace sustainable agricultural practices that promote moderate application of fertilisers to maintain healthy soils

Impact of Diverse Agricultural Land Uses on Soil Organic Matter Fractions: A Comprehensive Evaluation

Organic matter is a crucial component of soil that influences various soil properties and functions, including nutrient cycling, soil structure, water holding capacity and microbial activity. Different agricultural land uses significantly influence the quantity and quality of soil organic matter (SOM) fractions. The primary constituent of SOM is humic substances, also known as humus. These are stable compounds originating from the decomposition of organic matter derived from plants, animals, and microorganisms. The soil humic fraction is categorized into humic acid (HA), fulvic acid (FA) and humin (HN) based on the solubility in acid and alkaline medium. The structural arrangement, chemical constitution and stability of the humic substances in soil are affected by various factors, including climate, parent material, altitude, vegetation and the management practices employed in the area. In this context the present study was proposed to assess the impact of various agricultural land use systems on humic acid, fulvic acid and humin fraction in soils of different agro-ecological units (AEUs) of southern Kerala. The study focused on specific AEUs in southern Kerala, including the southern coastal plain (AEU 1), Onattukara sandy plain (AEU 3), southern laterites (AEU 8), south central laterites (AEU 9) and southern and central foothills (AEU 12). Within each AEU, various agricultural land use categories such as, coconut, rice, rubber and uncultivated land were selected as specific focal points for this investigation. The HA, FA and HN content in soil exhibited varying ranges across different AEUs, ranging from 0.57 to 2.06, 0.73 to 2.33, and 0.62 to 1.59 per cent respectively. Among the various land uses, rubber exhibited significantly higher levels of HA (1.72%), FA (2.01%) and HN (1.44%) compared to coconut, rice and uncultivated land. Among the different organic matter fractions, FA (32.30-36.18 %) contributed more towards SOM than HA (29.40-32.51 %) and HN (26.43-29.25 %).

Land Survey and Mapping for Agricultural Purpose using UAV

Unmanned Aerial Vehicles (UAVs) are a group of aerial vehicles that include drones. Agriculture has always been the backbone of India’s sustained growth. Land surveying is the most challenging task in the agricultural field in terms of accuracy and time required for surveying using the traditional method. We have built a fully autonomous UAV and calibrated it for agricultural land survey purposes. The navigation and mapping process, in which a predefined path is provided to the UAV flight controller. During its autonomous flight, the drone's camera captures multiple images. Using a threshold-based segmentation method, the cultivated land and uncultivated land areas are determined using this system. Pre-processing of the images, land area segmentation, and post-processing of the images are carried out. The pre-processed image is divided into several distinct regions by applying a colour thresholding technique, which serves as the foundation for the segmentation of land. The results illustrate that the proposed method outperforms the existing method.

Detecting land use land cover using supervised maximum likelihood algorithm on spatiotemporal imagery in Samarinda, Indonesia

Land use change commonly has an impact on urban areas. The land use and land cover (LULC) model should be used to address land problems. Land conversion is inextricably linked to Samarinda, Indonesia, the administrative center of the province of East Kalimantan. Additionally, this city serves as the new capital city’s Ibu Kota Nusantara-specific buffer zone. The current study aims to find and assess Samarinda City’s LULC. A supervised maximum likelihood technique was used to extract this data from spatiotemporal images. Both spatial and non-spatial data about changes in LULC are used in this study. The imagery data for the Samarinda region includes Landsat 5, 7, and 9 images from 1994 to 2022, along with administrative maps and GPS measurement data enabling on-the-ground checkpoints. Before classification analysis, radiometric and atmospheric correction, cropping, and layer stacking procedures were used to treat the image data. In supervised classification, the maximum likelihood method is applied to the four land classes of uncultivated vegetation, cultivated vegetation, waterbodies, and land with buildings. The research result indicates that the number of uncultivated land classes decreased by 6.38 percent and the percentage of cultivated land decreased by 5.52 percent, according to the study’s findings. On the other hand, the proportion of water bodies increased by 2.39 percent, and the proportion of built-up land classes increased by 9.51 percent. The overall and kappa accuracy test’s average value is 97.67%, higher than the required minimum of 75%.

Water and Salinity Variation along the Soil Profile and Groundwater Dynamics of a Fallow Cropland System in the Hetao Irrigation District, China

Managing soil salinity has always been a difficult problem for agriculture. Balancing water and salt while maintaining crop quality and yield is a key issue for agricultural sustainability. The Hetao lrrigation District in China has a complex mix of cultivated and uncultivated land which plays a crucial role in soil salinization processes. To investigate the dynamic properties of soil moisture and salinity, soil ions and groundwater, cultivated and fallow soils in the Hetao lrrigation District were analyzed, side by side, using a combination of field and laboratory tests, with data processed using univariate and multivariate statistical approaches. The results showed that soil moisture increased with increasing soil depth in both cultivated and fallow soils. Salinity showed an increasing trend in 2022 and 2023 from April to September. The soil ions were mainly sulfate in the cultivated soils and chloride in the fallow soils. The characteristic factors affecting salt accumulation in cultivated soils are Na++K+, Cl−, SSC, SO42−, HCO3−, and pH, and the characteristic factors affecting salt accumulation in fallow soils are Na++K+, Cl−, SSC, HCO3−, and pH. Water table depth varied with irrigation and precipitation and was strongly influenced by external environmental factors. Groundwater salinity remained stable throughout the study period. This study provides a theoretical basis for the prevention and control of soil salinization in arid and semiarid areas through the “dry drainage salt” measure.

The Role of Fallows in Sustainable Development

Abandonment of crop production on agricultural lands for several or more years is a widespread practice not only in Europe but also around the world. Economic and political considerations lead to the abandonment of crop production on the poorest lands, although sometimes agriculturally valuable lands are also excluded from farming. Fallow land can be afforested, designated as a dedicated protection area, exposed to natural succession, or used to grow biomass for energy purposes. However, the most important role of agricultural land should be to ensure food safety. The set-aside land with high production potential should be treated in a special way. While lying fallow, the soil can have its fertility sustained or even improved considerably. To this aim, uncultivated land should be properly protected by growing a permanent cover of plant species which will have a positive influence on the soil’s physical, chemical, and biological characteristics. Depending on the geographical location, different plant species will have a beneficial effect on set-aside soil. Given economic and environmental considerations, the best solution is to sow a mixture of grasses and legumes, which can improve substantially the biodiversity on fallow fields, raise the soil’s fertility, ensure high CO2 sequestration ratios, and influence beneficially the soil’s nutritional status and nutrient management. Soil protection can be provided for many years with little effort. The most recent reports implicate that it is possible to achieve several economic and environmental aims simultaneously in the course of the management of land excluded from agricultural production. These aims include the improvement of biodiversity, control of greenhouse gas emissions, generation of energy, and readiness to resume production of commodity plants. Proper management of fallows corresponds well with the challenges defined in the Green Deal for Europe or the US Green New Deal.

Land reclamation increased organic P fractions and phosphatase activities, and strengthened the co-occurrence networks of phoD community in calcareous soils

Organic phosphorus (Po) is an important constituent of P pool. Soil phoD community is primarily involved Po transformation. However, influences of agriculturally-driven land-use change on different Po fractions, phosphatase activities and phoD community are largely unknown. Here, an investigation was carried out containing three treatments: vegetable field (VF), cropland (CF) and uncultivated land (UL). Various Po fractions were measured by Hedley’s sequential extraction and 31P-NMR methods. The activities of alkaline phosphomonoesterase (ALP), acid phosphomonoesterase (ACP), phosphodiesterase activity (PD) and phytase were assayed; the abundance, and diversity of phoD community and its co-occurrence networks were analyzed. Compared with the UL treatment, soil total organic P (total-Po) in the VF and CF treatments significantly increased by 75.9% and 53.0%, respectively, mainly attributed to the increases in NaHCO3-Po, NaOH-Po and C.HCl-Po. 31P-NMR spectra showed that, when land was reclaimed from uncultivated land into agriculture fields (i.e., VF and CF), myo-inositol hexaphosphate (myo-IHP), α-glycerophosphate (α-glyc) and β-glycerophosphate (β-glyc) were increased by 9.5, 3.9 and 2.0 times, respectively. The activities of ACP, ALP and PD in the VF and CF treatments were higher than in the UL treatment. The α-diversity of phoD community was also significantly increased by land reclamation. Moreover, the linkage between soil Po and Po-cycling-related biological parameters (ACP, ALP and PD and phoD community) was more pronounced by NaHCO3-Po and NaOH-Po than the Po fractions measured by 31P-NMR method. Topological parameters (edges, node degree, and betweenness centrality) of phoD community’s network in the VF and CF networks were higher than in the UL network, implying that land reclamation favored to construct a more cooperative network of phoD community. Collectively, our findings demonstrated that when uncultivated land was converted to cropland, soil Po was notably increased, and phoD community’s co-occurrence network was also strengthened. The outcomes of this study emphasize that when land was reclaimed from nature (uncultivated land) into agriculture fields, the fertilization strategy of organic combined with chemical fertilizers application was beneficial for improving P fertility and assembling organic P-cycling related community.