Agricultura Resiliente ao Clima (ARC): avaliação das lavouras de sequeiro no estado do Ceará no periodo 1945 /2020

The process of determining whether a specific portion of land is suitable for a specific purpose is known as land suitability analysis (LSA). In order to promote sustainable development in semi-arid regions, the objective of this study is to analyse, evaluate, and identify the land for green growth based on topography, climate, and soil characteristics. Twelve thematic maps are prepared by using remote sensing satellite data. The Landsat 8 OLI/TIRS is used for the preparation of the thematic maps like land use land cover (LULC), normalized difference vegetation index (NDVI), top soil grain size index (TGSI), and geomorphology (GM), and DEM data is used for the preparation slope, and drainage density (DD). The collateral data is used to prepare geology and soil thematic maps. From the field work, we have collected soil samples for the compulsory physicochemical parameters such as soil EC and soil N-P-K which were taken into consideration and prepared thematic maps. The analytical hierarchy process (AHP) was used to generate the LSA of the research region, by assigning the appropriate weights to each criterion and sub-criterion for the thematic maps. Geographic information systems (GIS) and the multicriteria decision-making (MCDM) approach were used in the study's methodology. The LSA of the study area has been categories in to four types, i.e., highly suitable, moderately suitable, marginally suitable, and not suitable. The results revealed that 421.31 sq.km (40.09%) is not suitable for agriculture green growth in the study region, whereas 89.58 sq.km (8.52%) is moderately suitable, 267.66 sq.km (25.47%) is marginally suitable, and 266.54 sq.km (25.36%) is highly suitable. Accuracy assessment has validated the LSA map's accuracy (AA). The AA of LSA is 84.22%, which demonstrates a strong connection with the actual data. The research's results could be helpful in locating productive agricultural areas in various parts of the world. The decision-making AHP tool paired with GIS provides a novel method.

INTRODUCTION This chapter aims to capture the central issues that emerged from the papers, presentations and discussions at the International Conference on the Impacts of Climatic Variations and Sustainable Development in Semi-arid Regions (ICID), held in Fortaleza-Ceara, Brazil from 27 January through 1 February 1992 (see Preface). But, given the breadth and depth of the 76 papers and the wide-ranging discussions during the conference, this chapter could cover only a small subset of the issues that arose. We chose to focus on the plight of socially, politically, economically and spatially marginal populations in semi-arid lands, and the urgent need for environmentally sound and equitable development efforts. These themes recurred throughout the papers, presentations and discussions at the conference. This chapter draws from the materials and information presented at the conference, as well as the broader literature where relevant. While the themes within this chapter are derived largely from the conference, the arguments are shaped – as could not have been otherwise – by the experiences and perspectives of the authors. We did not try to represent the scope nor the depth of the issues covered at the conference, but rather, to characterize the problems and opportunities, and to explore what we felt were the most pressing concerns within the semi-arid regions of the world. Climate variability, natural resources and development in semi-arid regions Vulnerability to dislocation, hunger and famine are the most critical problems facing the inhabitants of semi-arid lands. These regions are subject to extreme variations in their relatively scant seasonal and inter-annual precipitation, resulting in recurrent droughts and floods.

Public Irrigation Projects (PIPs) play a strategic role in water security and rural development in semi-arid regions. However, the absence of standardized and replicable tools to assess governance performance and integrate social, ecological and institutional dimensions remains a challenge for sustainable management. To bridge this gap, this study proposes a framework for the quantitative operationalization of the Social–Ecological Systems (SES) approach through the development of the SES Governance Index (SGI), a composite indicator designed to assess adaptive governance in PIPs. The SGI is constructed through a procedure that translates SES components into measurable indicators using a conditional weighting protocol based on correlation analysis and dimensional diagnostics. Five subindices corresponding to core SES dimensions are developed using geometric aggregation, with weights determined according to the statistical structure of each dimension. These subindices are integrated into the final SGI through weighted linear aggregation. The framework is applied to nine PIPs in Brazil to demonstrate suitability for comparative assessment. Rather than producing a fixed ranking, the SGI is presented as a flexible metric for diagnosing governance structures and identifying systemic imbalances. By quantitatively operationalizing the SES framework, this study contributes a methodological tool for governance assessment in PIPs and other resource-dependent contexts.

The research aims to: a) assess the instabilities associated with rainfall and the variables that define the production of rice, beans, cassava and corn in the state of Ceará between 1945 and 2020; b) estimate models that can be used to make projections of harvested areas, yields and prices for these crops between 1945 and 2020; c) assess the impact of rainfall on the estimated forecasting models; d) assess how rainfall affects the likelihood of farmers making forecasts of the variables that define agricultural production. Rainfall data was obtained from the National Centers for Environmental Information (NOAA). Crop yield data came from the Brazilian Institute of Geography and Statistics (IBGE). Instabilities were measured by the coefficients of variation. ARIMA models (autoregressive, integrated and moving average model) were used to make the forecasts. The hypothesis that the residuals generated by the models are influenced by annual rainfall was tested. The results showed high instabilities in annual rainfall, which spread to the variables that define crop yields. Parsimonious and robust adjustments were obtained from a statistical point of view and it was shown that the errors generated, including their magnitudes, in the models used to forecast all the variables that define bean and corn yields, harvested areas and rice yields, as well as cassava yields, are influenced by annual rainfall in Ceará between 1945 and 2020.

This study aims to determine: (1) Rice, Corn and Soybean production before and after the construction of the Kanci-Pejagan Toll Road in Tanjung District, Brebes Regency and (2) Productivity Rice, Corn and Soybean before and after the construction of the Road Kanci-Pejagan Toll Road in Tanjung District, Brebes Regency. The study was conducted in Tanjung Subdistrict, Brebes Regency. The study was conducted from January to March 2020. The research design used in this study is a quantitative study with a sample of 35 farmers affected by toll road construction. Data collection techniques were carried out by direct interviews with sample farmers, and for supporting data obtained from libraries and agencies / agencies related to the problem under study. To find out the difference between Rice, Corn, and Soybean production and productivity before and after the construction of the Kanci - Pejagan toll road, different test analysis was used. To test the hypotheses about differences in production and productivity before and after the construction of the toll road used hypothesis testing with the t test approach. The results showed that: (1) Kanci - Pejagan Toll Road Development had an impact on Production Rice, Corn, Soybean: (a) Rice production increased by 2.40 tons (2.05%) after toll road construction. Different test results showed no difference in rice production before and after the construction of the toll road, (b) Corn production decreased by 4.04 tons (-6.59%) after the construction of the toll road. Different test results showed that there were differences in corn production before and after the construction of the toll road, (c) Soybean production increased by 0.19 tons (1.95%), after the construction of the toll road. Different test results showed that there was no difference in soybean production before and after the construction of the toll road, and (2) the construction of the Kanci - Pejagan Toll Road had a significant impact on Productivity Rice, Corn, Soybean: (a) Rice productivity increased by 1.01 ton / ha (20.95%). Different test results showed there were differences in rice productivity before and after the construction of the toll road, (b) Maize productivity increased by 0.91 tons (12.36%). Different test results showed that there were differences in corn productivity before and after the construction of the toll road, (c) Soybean productivity increased by 0.42 tons (21.71%) .The different test results showed there were differences in soybean productivity before and after the construction of the toll road.

Irrigation development in semi-arid regions provides benefits for producers as well as many others who reside in the region. Although a common perception exists that irrigation benefits only irrigation producers, a study carried out by Paterson Earth and Water Consulting Ltd showed that irrigation positively impacts many more sectors of the Alberta economy than just irrigation producers. Compared to dry land (rain fed) agriculture, irrigation creates increased employment and economic activity through the purchase of additional farm inputs as well as processing of agricultural products. Multi-use water storage reservoirs, which support irrigation agriculture, provide societal benefits through recreation, hydropower generation, and water supply for habitat development, communities and industries. This study estimated that Alberta’s irrigation industry, which represents less than 5% of the cultivated land base, generates about $3.6 billion to the provincial gross domestic product (GDP), accounting for about 20% of the total agri-food sector GDP. It is also responsible for generating about $2.4 billion in income and creating about 56,000 jobs. Many of these jobs and incomes are generated in the rural regions of the province, and serves as an important part of the rural development initiatives in Alberta. Almost 90% of the GDP generated by the irrigation sector accrued to the region and the province, and only 10% accrued to irrigation producers.

While hydropower is a cornerstone of global renewable energy strategies, its development in semi-arid regions remains insufficiently explored. Limited and highly variable water availability often discourages comprehensive assessments of its potential. In particular, run-of-river hydropower, despite its environmental and economic advantages, remains largely underexplored in these contexts due to its sensitivity to flow variability. This study evaluates the theoretical hydropower potential of run-of-river schemes within the semi-arid Grou watershed, a major tributary of the Bouregreg river in Morocco, with a focus on optimizing energy production under dry hydrological conditions. Hydrological modeling was applied using the Soil and Water Assessment Tool (SWAT), enabling the generation of flow-duration curves across the river network. These curves were then used to develop energy-duration curves, allowing for the identification of multiple optimal design flows. Consequently, instead of relying on a single turbine, the study explores the deployment of modular turbines per plant, each tailored to specific flow regimes, thereby expanding the range of exploitable run-of-river hydropower. Results indicate an untapped hydropower potential of approximately 32.4 MW per meter of head, with outputs of 31.5 MW, 783.3 kW, and 98.9 kW for high, moderate, and low flows, respectively. These findings highlight the feasibility of run-of-river hydropower in semi-arid regions and underscore the importance of adaptive turbine systems in enhancing sustainable energy production, specifically in water-scarce environments such as Morocco.

In previous studies, areas prone to soil piping were mapped on the catchment scale by integrating data-mining algorithms and geographical databases. However, this left the question of which input data layers are most influential on soil pipe distribution in semiarid regions, and how they can be exploited for accurate predictions of areas prone to piping. Here, a random forest (RF) procedure was applied to classify areas prone to piping using input data layers selected based on knowledge gained through previous theoretical modeling and empirical measurements. The input data layers were: potential incoming solar radiation; distance from the closest streambank; streambank slope gradient; topographic wetness index; flow accumulation; and vegetation cover as a proxy for the shading effect. An extensive dataset of field measurements (N = 774) was used to train and validate the RF classification procedure. Our results indicated that: (i) RF—based on carefully selected influential input data layers—can be used to map areas prone to soil piping at the catchment scale with high accuracy; (ii) the effect of potential solar radiation and—to a lesser extent—tree shading is noteworthy for soil cracking and subsequent piping development; and (iii) soil pipes were found at short distances (<30 m) from steep bank slopes due to the effect of tension cracks in the streambanks. These observations, over a wide region, further establish the effect of soil cracking, and drying and wetting processes, on soil pipe development in semiarid regions. Future studies applying piping susceptibility mapping at the catchment scale may benefit from using these input layers.

The growing disparity between water yield service (WYS) supply and demand poses a critical challenge to sustainable development in semi-arid regions. While inter-basin water transfer (IBWT) projects are widely implemented to alleviate water scarcity, their long-term impacts on WYS supply-demand dynamics under evolving land use patterns remain poorly quantified. This study addresses this gap by integrating land use simulations and ecosystem service modeling to assess future risks in the Fen River Basin, China. Using the PLUS model, we projected land use changes (2020-2030) under three scenarios: natural development (ND), ecological protection (EP), and economic growth (EG). The InVEST model quantified WYS supply, while demand was evaluated based on socioeconomic and land use data. A novel risk assessment framework incorporating IBWT effects revealed that rapid urbanization (notably cropland-to-artificial land conversion) could increase WYS demand by 12.0 × 108 m3 under the EG scenarios by 2030. IBWT implementation reduced high-risk areas by 18.7%, particularly in midstream urban zones, though downstream regions showed limited improvement (only 0.7%). Geodetector analysis identified land use change (q = 0.68) and IBWT (q = 0.31) as dominant drivers, with spatially heterogeneous influences-artificial land expansion critically impacted upstream areas, while temperature and topography governed midstream risks. Our findings emphasize the need for scenario-specific strategies: restricting urban sprawl, diversifying water sources, and enhancing policy coherence. This integrated approach provides actionable insights for balancing water security and ecological sustainability in water-stressed basins.

The meager availability of water as a heat transfer fluid is sometimes an impediment to enhanced geothermal system (EGS) development in semi-arid regions. One potential solution is in substituting CO2 as the working fluid in EGS. However, complex thermo-hydro-mechanical-chemical (THMC) interactions may result when CO2 is injected into the geothermal reservoir. We present a novel numerical model to describe the spatial THMC interactions and to better understand the process interactions that control the evolution of permeability and the heat transfer area. The permeability and porosity evolution accommodate changes driven by thermo-hydro-mechanical compaction/dilation and mineral precipitation/dissolution. Mechanical and hydraulic effects are demonstrated to exert a small and short-term influence on permeability change, while the thermal effects are manifest in the intermediate and short-term influence. The most significant and long-term influence on permeability change is by chemical effects, where decreases in fracture permeability may be of the order of 10-5 due to calcite precipitation in fracture throats, which causes the overall permeability to reduce to 70% of the initial permeability. The initial pressure and temperature of the injected CO2 exerts an overriding influence on permeability. In particular, an increased temperature reduces the mineral precipitation in the fracture and enhances mineral dissolution within the matrix and pore but results in mechanical closure of the fractures. Optimizing injection pressure and temperature may allow the minimization of precipitation and the maximization of heat recovery.

ABSTRACTVegetation plays an important role in the management of water resources and of the terrestrial vegetation degradation in semiarid regions of China. Detailed descriptions of the actual hydrological process of vegetation root water uptake (RWU) are lacking, and the dynamics of interfaces involved in the process of RWU have not received enough attention. A field in situ experiment with bare land and vegetated land was implemented to investigate soil water flow in vadose zones affected by vegetation RWU. The results revealed that, with the influence of RWU, the soil moisture content was redistributed and impacted evaporation and infiltration; therefore, even the roots were driven to utilize groundwater under intense potential evapotranspiration and water stress. Notably, the thicker vadose zones were beneficial for preserving water resources for bare land, but Salix reduced soil water storage by 1191.13 L compared with bare land, which was adverse for water resource development in semiarid regions. The results provide the basis for the protection of the vegetation environment and water resource management in arid regions.

The emergence of large-scale time-series data and advancements in computational power have opened new avenues for analyzing the spatiotemporal evolution of groundwater chemistry, water quality, and human health risks. This paper utilizes hydrogeochemical methods to elucidate the controlling factors of water chemical components based on the test results of 124 groundwater samples collected from 31 monitoring wells in Fuxin City, Liaoning Province, China, from 2018 to 2021. By integrating the Random Forest and Enhanced Water Quality Index methods for water quality assessment and employing the Human Health Risk Assessment (HHRA) model to analyze human health risks, our findings indicate that the groundwater is mildly alkaline, with SO4·Cl-Ca·Mg and HCO3-Ca·Mg as the dominant hydrochemical types, primarily derived from the dissolution of carbonate and silicate minerals such as dolomite, limestone, and andesite, and cation exchange reactions. The EI_RF water quality evaluation model reveals that the overall water quality in the study area is poor, with Class I and II water quality zones mainly located in the northeastern and central parts of the study area, showing a gradual transition from Class I and II in the northeast to Classes IV and V in the southwest, significantly influenced by NO3-, TH, TDS, and SO42-. The HHRA model results indicate that the potential non-carcinogenic risk of groundwater nitrates has a severe impact on infants, with the spatial distribution being low in the northeast and high in the southwest. Due to industrial activities, agricultural practices, and population growth, certain areas in developing countries such as China and India exhibit nitrate concentrations significantly higher than those in most international regions, highlighting global environmental and public health challenges. This underscores the importance of enhancing groundwater monitoring and implementing measures to mitigate pollution. These research outcomes hold significant implications for the government in formulating rational protection and management measures to ensure the sustainable utilization of groundwater resources.

Water scarcity and power availability are critical issues in agriculture, especially in developing countries.The need to reduce water and electricity consumption while increasing production necessitates innovative solutions.Solar photovoltaic (PV) water pumping systems present a viable option, offering costcompetitiveness, environmental benefits, and energy security.This study examines the techno-economic performance of a solar PV water pump installed at RTTC, Junagadh Agricultural University, from November 2019 to September 2022.The solar PV system, with a 5 HP, 3-phase AC motor, and 20 solar panels, was designed to operate without a battery, using a manual tracking system to optimize performance.The system's performance depended on solar radiation, total dynamic head, water requirements and sunshine hours.Data collected revealed that solar radiation, ranging from 257.53 to 1050.09W/m, significantly affected power generation and system efficiency.The average solar panel output ranged from 811.58 to 4532.79 W/32.8m, with the highest output during the Rabi season.Water horsepower (WHP) varied from 0.73 to 1.72 HP, depending on the season and time of day.Pump discharge rates varied between 2.02 to 4.18 liters per second (lps).The system's average array efficiency ranged from 8.26% to 11.64%, while pump efficiency ranged from 25.30% to 68.58%, with higher efficiencies observed in the morning due to lower head requirements.Overall system efficiency varied from 3.19% to 6.77%, with higher efficiencies during periods of increased solar radiation.Economically, the solar PV pump's operating cost was significantly lower (` 73.19/hour) compared to electric (` 80.18/hour) and diesel pumps (` 230.36/hour).Additionally, solar pumps are environmentally friendly, reducing carbon emissions associated with electricity and diesel use.Farmers in the South Saurashtra Agroclimatic Zone are recommended to adopt solar PV pumps for higher efficiency, lower operating costs, and environmental benefits.Optimal operation times are between 10 am and 4 pm, ensuring effective irrigation and maximizing system performance.This sustainable approach can significantly enhance agricultural productivity and support socio-economic development in semi-arid regions.

The present concern about environmental degradation has produced a renewed interest in organic fertilizers, such as animal manures. In addition, the soil organic matter conservation is one of the most important limiting factors for sustainability development in semiarid regions. In a previous experiment, carried out to evaluate the direct effects of application of manure rates in corn, positive effects of this fertilization were observed on green ear yield and grain yield. It was also verified that manure increased water retention and availability, and phosphorus, potassium, and sodium contents in the soil layer from 0-20 cm, but did not influence pH, calcium, organic matter contents and the sum of bases. The objective of this work was to evaluate the residual effect of applied fertilization on green ear yield and grain yield in cultivars AG 9012 and AG 4051. In both cultivars, a lack of manure residual effects was verified on total number and weight of green ears; number and weight of marketable ears, either unhusked or husked; plant height and ear height; fresh and dry matter in the above-ground part; and grain yield and its components. Cultivar AG 9012 performed best with regard to characteristics employed to evaluate green corn yield, and cultivar AG 4051 was superior with reference to plant height and 100-grain weight. The cultivars were not different with respect to the other traits evaluated.

The guava tree (Psidium guajava L.) is a tropical fruit tree of worldwide importance; however, the salinity of irrigation water severely limits its development in semi-arid regions. However, magnesium (Mg) can mitigate this stress by promoting plant photosynthetic activity. The objective was to evaluate the effect of foliar Mg in mitigating saline stress on photosynthesis and the growth of guava cultivar seedlings. The experiment was conducted in a randomized complete block design, in a 2 × 2 × 3 factorial scheme, with two guava cultivars (Kumagai and Paluma), two irrigation water salinity levels (a low-salinity control—0.5 dS m−1, and salt stress—2.5 dS m−1), and three doses of foliar Mg (0, 1, and 2 mL L−1), and six replications. A salinity of 2.5 dS m−1 reduced growth and gas exchange in both cultivars, with a reduction of approximately 30% in total dry mass, and 16% in CO2 assimilation rate. Supplementation with 1 mL L−1 of Mg attenuated the effects of stress, stimulating chlorophyll synthesis and gas exchange, reducing approximately leaf temperature in 3.5%, and vapor pressure deficit (VPD) in 12%. The Paluma cultivar was more responsive to Mg under salinity, with improved CO2 assimilation rate, stomatal control, and water use efficiency. Kumagai showed greater growth in height and diameter with 1 mL L−1 under stress. Foliar application of magnesium (1 mL L−1) is a promising strategy to produce guava seedlings under saline stress.