Semi-arid Climate Zones Research Articles

Critical needs to close monitoring gaps in pan-tropical wetland CH4 emissions

Abstract Global wetlands are the largest and most uncertain natural source of atmospheric methane (CH4). The FLUXNET-CH4 synthesis initiative has established a global network of flux tower infrastructure, offering valuable data products and fostering a dedicated community for the measurement and analysis of methane flux data. Existing studies using the FLUXNET-CH4 Community Product v1.0 have provided invaluable insights into the drivers of ecosystem-to-regional spatial patterns and daily-to-decadal temporal dynamics in temperate, boreal, and Arctic climate regions. However, as the wetland CH4 monitoring network grows, there is a critical knowledge gap about where new monitoring infrastructure ought to be located to improve understanding of the global wetland CH4 budget. Here we address this gap with a spatial representativeness analysis at existing and hypothetical observation sites, using 16 process-based wetland biogeochemistry models and machine learning. We find that, in addition to eddy covariance monitoring sites, existing chamber sites are important complements, especially over high latitudes and the tropics. Furthermore, expanding the current monitoring network for wetland CH4 emissions should prioritize, first, tropical and second, sub-tropical semi-arid wetland regions. Considering those new hypothetical wetland sites from tropical and semi-arid climate zones could significantly improve global estimates of wetland CH4 emissions and reduce bias by 79% (from 76 to 16 TgCH4 y−1), compared with using solely existing monitoring networks. Our study thus demonstrates an approach for long-term strategic expansion of flux observations.

Proposing design strategies for contemporary courtyards based on thermal comfort in cold and semi-arid climate zones

The relationship between urban geometry and microclimate is crucial in urban planning and climatology, significantly affecting outdoor comfort and energy consumption. Compact, dense buildings provide shading in summer, while openness is preferred in winter to maximize sunlight access. Courtyards, as climate-responsive structures, can create localized microclimates tailored to specific climatic conditions. Various components, including geometry, openness, orientation, wall materials, and green cover, influence the microclimate within a courtyard. While previous studies have primarily focused on hot and arid climates, there is a notable research gap concerning the thermal behavior of courtyards in cold and semi-arid regions. This study seeks to fill this gap by evaluating the impact of different courtyard geometries on outdoor thermal comfort specifically in semi-dry and cold climates by exploring optimal configurations for orientation, form, height-to-width ratios, and plan aspect ratios, the research offers strategies that improve both summer and winter microclimates. The study examined the combined effects of geometry and orientation on shading and wind speed in courtyards, modeling their influence on microclimates during warm summers and cold winters using ENVI-met software. Thermal performance indices, specifically PET and UTCI, were employed to assess the courtyards in Tehran. The findings reveal that a height-to-width ratio of 3:1 significantly improves thermal comfort, resulting in a UTCI difference of 19 °C. Furthermore, the model with a 2:1 plan aspect ratio exhibited a UTCI that was 6.7 °C lower than that of the 3:1 ratio. These findings provide valuable insights for designing contemporary courtyards that optimize thermal comfort in similar climates.

A novel framework for developing a machine learning-based forecasting model using multi-stage sensitivity analysis to predict the energy consumption of PCM-integrated building

Accurate machine learning (ML) predictions for the early stages of the building design are crucial to construct energy-efficient buildings utilizing limited resources. Several studies have employed ML methods for energy consumption (EC) prediction without considering the utmost crucial PCM-integrated building design parameters. In addition, reducing the dataset by considering only the most significant building design parameters before applying the ML-based method would be beneficial for reducing the computational power and memory usage of the system as well as utilizing less time in the modelling process. To this end, this research presents a novel framework to establish the most robust and reliable ML-based prediction model with less complexity, considering only the most influential PCM-integrated building design parameters. These parameters were identified for future scenarios of hot semi-arid (BSh) climate zones using multi-stage sensitivity analysis. Afterward, a reduced EC database based on the most significant building's early-design-stage parameters (EDSPs) was utilized to formulate several multi-expression programming (MEP) and support vector machines (SVM)-based forecasting models, considering the variations in their hyperparameter values. Formulated prediction models have shown less time utilization through the training and testing phases for the EC evaluations of selected PCM-integrated building compared to the physical-modelling process. Several statistical parameters were used to test and validate the performance of the formulated prediction models. The acquired model evaluation and validation results demonstrated that the MEP-based prediction model (MEP15) exhibited the highest level of reliability and accuracy, showing an R2 value of >95% for both the training and testing phases. The model's interpretability showed that, throughout the parametric analysis, the developed prediction model adhered to the system's physical boundary constraints. Also, the best-performing prediction model showed energy savings of up to 12% for building integrated with PCM having a melting temperature of 28 °C. Conclusively, this research demonstrated that the developed MEP-based prediction model could be employed to precisely forecast the EC for selected PCM-incorporated building in the whole BSh climate, considering important EDSPs while utilizing minimal resources.

Resistance of grassland productivity to drought and heatwave over a temperate semi-arid climate zone

Drought and heatwave are the primary climate extremes for vegetation productivity loss in the global temperate semi-arid grassland, challenging the ecosystem productivity stability in these areas. Previous studies have indicated a significant decline in the resistance of global grassland productivity to drought, but we still lack a systematic understanding of the mechanisms determining the spatiotemporal variations in grassland resistance to drought and heatwave. In this study, we focused on temperate semi-arid grasslands of China (TSGC) to assess the spatiotemporal variations of grassland productivity resistance to different climate extremes: compound dry-hot events, individual drought events, and individual heatwave events that occurred during 2000–2019. Based on the explainable machine learning model, we explored the resistance to the interaction of drought and heatwave and identify the dominant factors determining the spatiotemporal variations in resistance. The results revealed that grassland resistance to climate extremes had decreased in Xilingol Grassland and Mu Us Sandy Land, and had a not significant increase in Otindag Desert during 2000–2019. Human activities and the increase in CO2 concentration causes a decline in resistance in Mu Us Sandy Land, and the increase of VPD and shift of vegetation loss event timing caused a decline in resistance in Xilingol Grassland, while the weakening of climate extremes, especially the shortening of drought duration, increase the resistance in Otindag Desert. Mean annual temperature dominates the spatial differences in resistance among different grasslands. When drought and heatwave occur simultaneously, there is an additive effect on resistance and causes lower resistance to compound dry-hot events compared to individual drought and heatwave events. Our analysis provides crucial insights into understanding the impact of climate extremes on the temperate semi-arid grasslands of China.

Ratio of immune indices in women of the semi-arid region

Environmental and climatic factors have a significant impact on the immune system, shaping its composition and functions. The semiarid region of Aleppo, characterized by hot, dry summers and moderate, wet and cold winters, is also characterized by environmental pollution such as air pollutants and industrial chemicals. The interaction of these environmental and climatic factors can impair immune function by causing inflammatory responses, compromising the integrity of immune cells, and impairing the body’s ability to mount an effective immune response. To date, the physiological characteristics of the parameters of the human blood system and the development of physiological reactions of adaptive immune homeostasis depending on the territory of residence have not been sufficiently studied. In this work, we studied the state of immune indices in women living in the semi-arid region. Thirty women aged from 20 to 60 years without chronic and acute diseases were examined. Immunocompetence was assessed using white blood cell count, lymphocyte subset analysis and calculation of immune indices including neutrophil to lymphocyte ratio (NLR), lymphocyte to monocyte ratio (LMR), systemic inflammatory response index (SIRI), immunoregulatory index (CD4+/ CD8+) and lymphoproliferation ratio and apoptosis (CD10+/CD95+ and CD71+/CD95+). The results of the analysis showed that the median NLR was 2.18 (1.50-2.90), LMR 6.66 (5.47-8.87), SIRI 0.64 (0.45-0.98), immunoregulatory index 0.99 (0.84-1.27) and the ratio of lymphoproliferation processes to apoptosis (CD10+/ CD95+ and CD71+/CD95+) 0.95 (0.65-1.29) and 0.94 (0.78-1.11), respectively, which indicates a stressful state of immune homeostasis and signs of premature aging of the immune system. Neutrophil-lymphocyte ratio (NLR), lymphocyte-monocyte ratio (LMR), systemic inflammatory response index (SIRI), immunoregulatory index (CD4+/CD8+) and lymphoproliferation-apoptosis ratio were determined. (CD10+/ CD95+ and CD71+/ CD95+) in the examined women of the semiarid climate zone of residence, emphasizes the stressful level of immune homeostasis. The results obtained highlight the need for systematic individual biomedical monitoring to maintain immune homeostasis in populations inhabiting similar environmental conditions.

A dataset of annual TCI, VCI, VHI and TVDI with the resolution of 1 km in the Yellow River Basin (2003–2022)

Primarily situated in arid and semi-arid climatic zones, characterized by naturally limited water resources, the Yellow River Basin is the most drought-affected among China's major basins. As global environmental and climate change continue to evolve, droughts in the Yellow River Basin have become increasingly frequent, making drought monitoring research a current focal point. Based on MODIS vegetation data and surface temperature products, this dataset undergoes quality control procedures such as cloud removal and data reconstruction to collect the data of annual Temperature Condition Index (TCI), Vegetation Condition Index (VCI), Vegetation Health Index (VHI) and Temperature Vegetation Dryness Index (TVDI) in the Yellow River Basin from 2003 to 2022. The spatial scope of this dataset ranges from 32°10′N–41°50′N，95°53′E–119°05′E. The dataset is in GeoTiff format with a spatial resolution of 1km. It can provide foundational data and scientific support for drought disaster monitoring in the Yellow River Basin.

Advancing toward a sustainable future in subtropical semi-arid type climatic zone: Iraq case - The progress of solar photovoltaic energy implementation

The study delves into Iraq's shift towards sustainable energy, focusing on solar photovoltaic energy adoption and expansion to meet rising energy demands and the need for cleaner energy solutions. It highlights the potential of harnessing solar energy, particularly through small-scale solar PV systems, supported by incentives like net metering programs that encourage surplus energy feed-in to the grid. Using Geographic Information System data, the paper examines the spatial distribution of solar PV installations and projects the capacities of rooftop solar PV systems by 2035 under various promising scenarios. It also demonstrates the link between increased solar PV capacity and meeting national energy demands, underscoring the importance of strategic policies, technological advancements, and the engagement of consumers and businesses in driving Iraq towards a sustainable energy future. By fostering an environment conducive to solar PV adoption, the results offers valuable insights for ongoing discussions and future studies on renewable energy strategies in Iraq.

Effects of Childcare Hands-On Gardening on Preschoolers' (3-5 Years) Physical Activity in Semi-Arid Climate Zone.

How hands-on gardening impacts behaviors including healthy eating and physical activity during early childhood can be of critical importance for preventing the early onset of obesity. This study investigates how participating in hands-on gardening impacts preschoolers' (3-5 years old) physical activity (measured by accelerometers) in childcare centers in the semi-arid climate zone. The research was conducted in eight licensed childcare centers located in West Texas with 149 children (n = 149). Four childcare centers in the experimental group received hands-on garden interventions; the other four in the control group did not. In both experimental (intervention) and control (non-intervention) centers, children wore Actigraph GT3X+ accelerometers continuously for 5 days before and for 5 days after intervention (a total of 10 days). Results show that the duration of sedentary behavior of children in the experimental (intervention) group significantly decreased compared to children in the control (non-intervention) group. The finding suggests that the positive effects of childcare hands-on gardening on physical activity extend to semi-arid climate zones where gardening is challenging due to high temperatures and lack of annual rainfall. The research emphasizes the critical need to incorporate hands-on gardening in childcare centers as an obesity prevention strategy nationally in the US and beyond.

Climatic Data Trend Analysis by Mann Kendal Test and Innovative Trend Analysis: A Case Study of Taloqan River at Takhar, Afghanistan.

Climate change is taking place due to increased population and anthropogenic activities. The impacts of climate change have increased the demand for sustainable management of water resources. The semi-arid climatic zone is widely affected by climate change. Afghanistan is vulnerable to climate change because of its climate and variable precipitation. This research has studied the trend analysis of climatic data in the Taloqan River, which is being utilized for drinking and irrigation. The recorded data of the Tangi-Farkhar hydro meteorological station from 2008 to 2021 is used in this work. The non-parametric Mann-Kendall (MK) trend test and the Innovative Trend Analysis (ITA) method are utilized in this investigation. This study has found an increasing trend in the mean value of temperature in May across the period of study but no trend in annual temperature data according to the MK test with a 95 percent confidence level. The ITA shows an increasing trend in the annual temperature data, a decreasing trend in precipitation, and a non-monotonic negative increasing trend in discharge. The MK test has presented no trend in the annual data of precipitation and discharge and showed an increasing trend in the mean discharge value in October and November across the study period.

Comparative analysis of energy performance between clay-based and conventional building materials: A case study in Moroccan semi-arid climate

The environmental challenges arising from using traditional construction materials, such as cement, along with their rapid depletion, underscore the necessity of employing environmentally friendly building materials derived from natural resources. In this context, this study presents a comparative analysis of the energy performance of conventional building materials and clay-based materials. Focusing specifically on the Beni Mellal region, adobe bricks reinforced with straw, at weight percentages of 0%, 2%, and 4%, were manufactured. First, the physicochemical properties of the investigated clay were characterized. Subsequently, the thermophysical properties of the fabricated bricks were determined. Annual simulations were conducted using the TRNSYS software, considering a typical meteorological year (TMY) for Beni Mellal City, located in the semi-arid climatic zone. The energy performance of various passive energy efficiency measures was evaluated and discussed, facilitating a thermal analysis to assess the energy needs for heating and cooling inherent to each building material. The results demonstrate that clay bricks, particularly those reinforced with 4% wheat straw, outperform conventional materials in terms of energy efficiency, highlighting their potential for sustainable construction. This study emphasizes the significance of local clay resources and natural reinforcements in enhancing energy efficiency and provides insights into their application in eco-friendly construction practices, thereby contributing to sustainable development goals

Geçiş İklimi Koşulları Altında Farklı Akarsu Yataklarında Yer Alan Toprakların Verimlilik Özellikleri

This study was conducted to identify and evaluate some of the fertility characteristics of soils in stream beds in Şebinkarahisar district of the Giresun province of Türkiye, which has a transitional climate between semi-arid and humid climate zones. To this end, a total of 48 soil samples, surface (0-30 cm) and subsurface (30-60/61/62/65 cm), were collected from 24 different sampling points on various stream beds. The textures of the surface and subsurface soils taken were determined as CL, SL, SCL, L, C, and LS. pH values of surface soils ranged from 5.84 to 7.98, and the pH values of subsurface soils ranged from 6.06 to 8.05. Lime contents of the soils without salinity problem ranged from 0.00% to 38.30% for surface soils, and from 0.00% to 37.90% for subsurface soils. Organic matter contents varied between 0.32% and 4.16% for surface soils, and between 0.14% and 2.16% for subsurface soils. While the soils were poor in total nitrogen, phosphorus, zinc and manganese, it was determined that the calcium and copper contents were at sufficient levels. Although deficiencies were detected in some soils for potassium, magnesium and iron, they were generally determined to be at sufficient levels. To deal with deficiencies of macro and micro plant nutrients, including deficiency of organic matter, a fertilization planning is recommended that includes barnyard manure, poultry manure, green manure, compost, vermicompost, and various organic fertilizers containing macro and micro elements. Within the scope of the research, climate classifications were also made according to Thornthwaite, De Martonne-Gottman and Erinç methods by had used 48 years (1965-2012) climate data of Şebinkarahisar district. Plant species and varieties to be grown in the study area should be selected from among those suitable to the transitional climate conditions prevailing in the region. It will also be useful to analyze the stream waters in the areas where soil sampling is done.

Greening of China and possible vegetation effects on soil moisture

Wetting and drying climate sequences and anthropogenic vegetation changes can have profound effects on the hydrological cycle and sustainability of terrestrial ecosystems. China contains many different climates, from humid to extremely arid and it contributes to the global mitigation strategies of climate change. China is also an important contributor to global greening and carbon sequestration. In view of this, we estimated the spatial and temporal variation of leaf area index (LAI), dryness/wetness index (DWI), and soil moisture (SM) in arid (A), semi-arid (SA), semi-humid (SH), and humid (H) climate zones during 1981–2018 in China and analyzed the patterns of DWI and LAI effects on SM under different vegetation greenness. The results showed a significantly increasing trend of LAI in all climatic zones, and the contribution was from highest to lowest: SH (8.17 × 10-3 m2 m−2 year−1), SA (7 × 10-3 m2 m−2 year−1), H (4.71 × 10-3 m2 m−2 year−1), and A (3.98 × 10-3 m2 m−2 year−1). The SA and A zones are becoming wetter, while the soil of SH and H zones are drying. The dry/wet climate variation plays a decisive role in soil moisture, while the role of vegetation is limited. Additionally, the LAI3 (mean LAI from 2016 to 2018) thresholds were 0.25–0.41 and 0.84–0.86 for A and SA as a whole, respectively, as well as 0.47–0.54 and 0.93–1.18 for grassland, respectively. When vegetation exceeded this threshold, the effect of vegetation on soil moisture showed a shift from increasing to decreasing change. Overall, the results of the study provide improved understanding of the atmosphere-soil-vegetation interactions under climate change, as well as effects of vegetation restoration and water conservation efforts.

Estimation of bark water storage capacity of broad- and needle-leaved trees planted in a semi-arid climate zone

In forest ecosystems, measurement of bark water storage capacity (BWSC) is required for determining the amount of rainfall interception and understanding throughfall and stemflow processes. We compared the bark roughness coefficient (BRC) and BWSC of even-aged, widely-planted, broad-leaved and needle-leaved species in the Chitgar Forest Park, near Tehran, Iran. Bark samples (n = 10 per species) were extracted from three needle-leaved species (Cupressus arizonica, Thuja orientalis, and Pinus eldarica) and two broad-leaved species (Acer velutinum and Robinia pseudoacacia). The highest and lowest BWSC was found to be for A. velutinum and P. eldarica trees, respectively (0.63 vs. 0.32 g cm−3). Among the studied species, R. pseudoacacia had the highest BRC (0.69), and the lowest was found to be for A. velutinum species (0.03). The whole tree bole BWSC ranged from 156.8 L for P. eldarica to 14.6 L for A. velutinum. The results suggested that A. velutinum may provide more stemflow to the forest floor due to its small size, low BRC and subsequent low whole tree bole BWSC. These findings significantly contribute to our understanding of rainfall partitioning dynamics and ecohydrological processes associated with stemflow from trees. This improved understanding will help managers in selecting tree hydrologic characteristics that align with their objectives in forestry treatments, afforestation plans and establishment of vegetation in urban park settings within drylands.

Appraisal of irrigation land suitability of semi-arid climatic zone of Rajasthan, India

Abstract Planning how to use the land resources that are available for irrigation is crucial for reducing the problem of food security. Analytical hierarchy process methodologies were used to undertake an analysis of the appropriateness of land using the GIS approach. Each parameter's weight was assessed using a 6 × 6 pairwise comparison matrix because six parameters, including slope, distance to the nearest road, land use land cover, population density, soil texture and rainfall deficit, are taken into account. After all, the weighted overlay approach of the GIS application was used to create the ultimate land suitability map for irrigation. Using the natural break classification approach, the final map was divided into land suitability classes. Of the entire region, 12.9% fell into the highly suitable (S1) class, 85.14% fell into the moderately suitable (S2) class, and 2.57% fell into the least suitable (S3) class. The finding of the study will play a significant role in performing irrigation taking into account the input parameters and ultimately defining suitable land classes and lands that may be used in accordance with current irrigation technology.

“Ground Water Development Techniques under Water Cup” Bidal Village Dist. Satara

Abstract: Paani Foundation is a non-profit, non-governmental organization actively engaged in drought prevention and watershed management in the state of Maharashtra, India. Founded by Indian actor Amir Khan and his wife Kiran Rao, the foundation is led by CEO Satyajit Bhatkal. The state of Maharashtra has a history of recurring droughts and severe water scarcity over the past few years, including the significant drought in 2013. Approximately one-third of the state falls within the semi-arid climatic zone. Due to the impact of climate change, rainfall patterns have become increasingly erratic. The state's irrigation coverage is only 16% of the total cultivated area, significantly lower than the national average of 42%. As a result, there has been excessive use of bore wells, leading to a rapid decline in groundwater levels. In 2015, the state government officially declared that 60% of its villages were facing a "drought-like condition," meaning their crop yields were less than 50% of the normal yield in the state. This condition currently affects 23,811 out of the state's 39,453 villages, resulting in a significant drop in agricultural output for the year, as stated by officials.

An overview of groundwater response to a changing climate in the Murray-Darling Basin, Australia: potential implications for the basin system and opportunities for management

The Murray-Darling Basin (MDB) is a highly allocated and regulated, mostly semiarid basin in south-eastern Australia, where groundwater is a significant water resource. Future climate predictions for the MDB include an expansion of arid and semiarid climate zones to replace temperate areas. The impacts of climate change are already evident in declining groundwater levels and changes in the connection status between rivers and groundwater, and modelling has predicted a further reduction in future groundwater recharge and ongoing declines in groundwater levels. This is predicted to further reduce river baseflow and negatively impact groundwater-dependent ecosystems (GDEs), and these system responses to a changing climate and extreme events are complex and not always well understood. This report provides an overview of the current state of knowledge of groundwater response to a changing climate for the MDB, and outlines challenges and opportunities for future groundwater research and management. Opportunities for the region include improving data systems and acquisition through automation and novel data sources, and growing capability in integrated, risk-based modelling. Quantification of the groundwater/surface-water connection response to declining groundwater levels, and assessing GDE water requirements and thresholds, would enable identification of vulnerable systems and inform the development of metrics for adaptive management, improving the ability to respond to climate extremes. There is potential to adapt policy to support active management of groundwater where required, including conjunctive use and water banking. Improving knowledge sharing and water literacy, including understanding community values of groundwater and GDEs, would support future decision-making.

Challenges in the Sustainable Economy of Northern Ghana– Impacts of Soybean Trade on Bambara Groundnut: A Case Study

The global seed trade has reached and conquered Northern Ghana, squeezing out local suppliers. Considering ongoing population growth, rapidly urbanizing communities, changing diets, and vast quantities of imported food products, the endeavours of enterprises that try to reduce the local food production deficit should be more appreciated. Rice, maize, and soybeans are three types of grain that dominate the global seed trade. Furthermore, the natural conditions and vegetation of the sub-tropical region are close to optimal. While rice and maize have been cultivated for a long time, soybeans are a new crop in the semi-arid climate zone of the Guinea-Savannah.The motivations and ambitions are clear: pushing improved soybean seeds into the traditional farming system of Northern Ghana to meet the zero hunger sustainable development goal while widening the market for western seed producers. In the Ghanaian context, microfinance is built on making customers dependent on services. On the bone hand, it is a tool to extend farm sizes through mechanization, fertilizers, and modern cultivation technologies to increase yield; on the other hand, microfinance could cause financial difficulties within society and farmer associations, and it has negative effects on unsupported and unfinanced activities such as cultivating indigenous crops.

Impact of Climate Change on Crop Yields: Insights from the Abruzzo Region, Central Italy

Climate change poses a major sustainability challenge, with potential far-reaching economic and social impacts, including fluctuations in agricultural yields and subsequent volatility in the availability and prices of essential food resources. In this study, we analyze the changes in climatic variables and agricultural yields for main crops cultivated in the Abruzzo Region (Central Italy), as well as their reciprocal correlation pattern in the time range, 1952–2014. Central Italy exhibits a well-developed agricultural sector and is characterized by a Mediterranean climate; given its proximity to the semi-arid and arid North African climate zone, such a region may be particularly vulnerable to climate change impacts. The analysis reveals an increase in drought intensity and persistence, starting from the 1980s, with a shift towards more temperate conditions in winter months and a transition to a warmer and more arid climate during the summer season. Moreover, the study identifies an overall increase in the correlation magnitude between crop yield fluctuations and climatic variables in the period 1983–2014 compared to that during the previous thirty-year time range. This finding can be interpreted as a change in the resilience (or increased vulnerability) of the agricultural production system to climate change. This work can be thus considered as an interesting case study in the Mediterranean region, offering valuable insights for constructing probabilistic models of fluctuations in agricultural production possibly induced by climate change.

Evaluating the Primary Macronutrients and their Correlations with pH, Electrical conductivity, Organic Carbon and Soil Nutrient index in the Arid and Semi-Arid Climatic Zones of Anantapur District, Andhra Pradesh, India

In the year 2022, the study was carried at Agricultural Research Station, Anantapur aimed to assess macronutrient levels and their correlation with soil physico chemical properties in the arid and semi-arid regions of Anantapur district, Andhra Pradesh. A total 42 samples were collected from farmers field under different land use. The soil analysis revealed a pH range of 6.53 to 8.94, with a mean pH of 7.89 and a majority of samples exhibiting alkaline properties. Soil electrical conductivity (EC) varied from 0.05 to 0.83 dS/m, with a mean EC of 0.22 dS/m, and most samples falling within the non-saline and very low salinity categories. Organic carbon content ranged from 0.07% to 1.15% with a mean of 0.38%, and a significant proportion of samples displayed low organic carbon levels. Available nitrogen content ranged from 50.4 to 264.6 kg/ha (mean: 139.44 kg/ha), mostly below the critical threshold. Phosphorus availability was medium (range: 16.1 to 44 kg/ha, mean: 29.97 kg/ha), while available potassium content varied widely (range: 15.68 to 311 kg/ha, mean: 129.65 kg/ha), with a substantial proportion of samples indicating low levels. The nutrient index categorized nitrogen and potassium as low in fertility and phosphorus as medium, reflecting values of 0.71, 1.37, and 1.09 (L, M, L) respectively. Correlations showed EC negatively related to pH (-0.056), while organic carbon positively correlated with EC (0.288*), and nitrogen displayed positive correlations with both organic carbon (0.283*) and pH (0.257). Phosphorus exhibited a positive correlation with organic carbon (0.224), and potassium displayed robust positive correlations with EC (0.592**) and moderate positive correlations with organic carbon (0.392**), nitrogen (0.311*), and a slight negative correlation with pH (-0.253). This result helps to understand nutrient status in the arid and semi-arid areas of Anantapur and recommended to incorporate compost, crop residues and green manure crops and use cover crops as live mulching helps to increase organic carbon, nitrogen and potassium and it also decrease nitrogen losses through volatilization.

Analysis of Vegetation Dynamics and Driving Mechanisms on the Qinghai-Tibet Plateau in the Context of Climate Change

The Qinghai-Tibet Plateau (TP) is susceptible to climate change and human activities, which brought about drastic alterations in vegetation on the plateau. However, the trends and driving mechanisms of vegetation changes remain unclear. Therefore, the normalized difference vegetation index (NDVI) was used to analyze the spatiotemporal distribution of vegetation and the consistency of dynamic trends in the TP from 2000 to 2020 in this study. The independent contributions and interactive factors of natural and human activities on vegetation changes were investigated through the Geodetector model. The drivers of vegetation under different dry–wet zones and precipitation gradients were quantitatively separated, and the internal mechanisms of vegetation changes were discussed from multiple perspectives. The results showed that from 2000 to 2020, the NDVI had an overall increasing trend, with an increasing rate of 0.0027 a−1, and the spatial pattern was different, increasing gradually from the northwest to the southeast. Consistent improvement occurred in the central and southeastern parts of the TP, while the western and northern parts consistently deteriorated. The annual mean precipitation had the greatest explanatory power for vegetation changes (0.781). The explanatory power of the integrated effects between two factors was greater than that of individual factors. The integrated effects between annual mean precipitation and other driving factors had the strongest explanatory power on vegetation variations. The driving mechanisms of vegetation dynamics varied among different dry–wet zones, and the vegetation growth was more sensitive to the response of precipitation in arid and semi-arid climate zones. This study enhances our understanding of the intrinsic mechanisms of vegetation changes on the plateau, which can provide a reference for ecological conservation, and has implications for further prediction and assessment of vegetation ecosystem stability.