Changes In Water Management Research Articles

Comparing model complexity for glacio-hydrological simulation in the data-scarce Peruvian Andes

Study regionGlaciated headwaters of the Vilcanota-Urubamba river basin, Southern Peru Study focusA pivotal question is if robust hydrological simulation of streamflow in data-scarce and glaciated catchments can be achieved using parsimonious or more complex models. Therefore, a multi-model assessment of three glacio-hydrological models of different complexity was conducted thoroughly analyzing model performance, flow signatures and runoff components. New hydrological insights for the regionIn data-scarce catchments, such as in the tropical Andes, parsimonious glacio-hydrological models can provide more robust results than complex models. While the overall performance of all models was reasonably good (R2: 0.65–0.70, Nash-Sutcliffe: 0.65–0.73, Nash-Sutcliffe-ln: 0.73–0.78), with increasing data scarcity more complex models involve higher uncertainties. Furthermore, complex models require substantial understanding of the underpinning hydrological processes and a comprehensive calibration strategy to avoid apparently high model performance driven by inadequate assumptions. Based on these insights we present a framework for robust glacio-hydrological simulation under data scarcity. This stepwise approach includes, among others, a multi-model focus with a comprehensive assessment of flow signatures and runoff components. Future modeling needs to be further supported by alternative data collection strategies to substantially improve knowledge and process understanding. Therefore, the extension of sensor and station networks combined with the integration of co-produced knowledge represents a meaningful measure to robust decision-making for climate change adaptation and water management under high uncertainty.

Climate Change Effect on Irrigation Water Requirement of Wheat and Maize in Northern Part of Bangladesh

Bangladesh is one of the most vulnerable countries for climate change in agricultural water management. A research had been done to assess climate change effects on irrigation water use of wheat and maize in the northern part of Bangladesh. The twenty nine years of data (1990-2018) were analyzed with Mann-Kendall test as well as Sen’s slope for climate change impact and the responsible weather parameters due to climate change were identified with correlation coefficients. The crop water requirement of wheat in Bogura and Rangpur was declining at the rate of 3.3mm and 2.3mm per decade respectively. Net irrigation water requirement of wheat at both Bogura and Rangpur was inclining at the rate of 1mm and 10mm per decade respectively because the effective rainfall of these regions was decreasing at 5mm and 11mm per decade respectively. The crop water requirement of maize for similar districts was increasing at the rate of 3.2mm and 2.5mm per decade respectively although net irrigation water requirement had statistically non-significance for climate change effect. The weather parameter, which was mainly responsible for climatic change in irrigation water requirement, was increasing temperature. Therefore, wheat cultivation might be coped with climate change in the northern part of Bangladesh rather than maize on the basis of irrigation and water management.

ATTRICI v1.1 – counterfactual climate for impact attribution

Abstract. Attribution in its general definition aims to quantify drivers of change in a system. According to IPCC Working Group II (WGII) a change in a natural, human or managed system is attributed to climate change by quantifying the difference between the observed state of the system and a counterfactual baseline that characterizes the system's behavior in the absence of climate change, where “climate change refers to any long-term trend in climate, irrespective of its cause” (IPCC, 2014). Impact attribution following this definition remains a challenge because the counterfactual baseline, which characterizes the system behavior in the hypothetical absence of climate change, cannot be observed. Process-based and empirical impact models can fill this gap as they allow us to simulate the counterfactual climate impact baseline. In those simulations, the models are forced by observed direct (human) drivers such as land use changes, changes in water or agricultural management but a counterfactual climate without long-term changes. We here present ATTRICI (ATTRIbuting Climate Impacts), an approach to construct the required counterfactual stationary climate data from observational (factual) climate data. Our method identifies the long-term shifts in the considered daily climate variables that are correlated to global mean temperature change assuming a smooth annual cycle of the associated scaling coefficients for each day of the year. The produced counterfactual climate datasets are used as forcing data within the impact attribution setup of the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP3a). Our method preserves the internal variability of the observed data in the sense that factual and counterfactual data for a given day have the same rank in their respective statistical distributions. The associated impact model simulations allow for quantifying the contribution of climate change to observed long-term changes in impact indicators and for quantifying the contribution of the observed trend in climate to the magnitude of individual impact events. Attribution of climate impacts to anthropogenic forcing would need an additional step separating anthropogenic climate forcing from other sources of climate trends, which is not covered by our method.

Socio-environmental dynamics in the central Atacama desert (22°S) during the late Holocene

In the Central Atacama Desert (22°-24°S; henceforth CAD), around 3700 cal yrs BP, human economies begin to transition from relying mostly on hunting and gathering to increasingly incorporating horticulture and pastoralism became more intensive during the Late Intermediate Period (LIP; beginning at ca. 1050 cal yrs BP/900 AD). In this extreme environment, the well-being of past and present farming and herding communities is directly tied to water availability. The lack of proper paleoclimatic/environmental records in terms of their temporal/spatial resolution impeded evaluation whether sedentarization was synchronous, in some degree, with the amelioration of dry conditions recorded during the Late Holocene at millennial timescales. The present paper thus aims (1) to reconstruct the past environmental and climatic dynamics in the CAD (22°S) during the late Holocene at millennial to sub-centennial scales based on the pollen record of fossil rodent middens of Cuesta Chita site and; (2) to discuss their possible relationship to changes in cultivation and water management as seen at the archaeological sites of Topaín, Paniri and Turi, located in the Salado River basin. The CCH rodent midden pollen record reflects wetter (drier) than present phases around 4400, 3650, 3000, 2200–2100, 1600, 855–840, 520–450 and 100 cal yrs BP (980, 450-115 cal yrs BP). By the time that wetter-than-present conditions occurred in the CAD (Formative Period, 3500-1050 cal yrs BP), local communities had already developed small-scale horticultural practices, yet they did not develop extensive or intensive agricultural practices. Indeed, historical processes leading to economic transformations and the rapid adoption of intensive agriculture throughout the CAD after 1000 cal yrs BP occurred and were probably favored by wetter than present conditions, suggesting positive correlations between climatic and cultural change. However, these correlations are complex and non-deterministic. In fact, decreased moisture between 650 and 600 cal yrs BP in the Turi Basin was met by agropastoralists at Topaín with complex local strategies that included changing water management practices and significantly extending farmed lands. Similarly, the Topaín fields were abandoned during a period of much-wetter-than-present conditions. The chronologically fine-grained comparison of the CCH and archaeological records reveals that the relationship between climate and culture is complex, non-deterministic, and historically contingent, with examples of agricultural expansion during a time of water stress, and the abandonment of fields during a time of abundance.

Ecohydraulic tools for aquatic fauna habitat and population status assessment, analysis and monitoring aimed at promoting integrated river management

The ecohydraulic modeling framework in ecological systems includes hydro-morphodynamic, habitat, and population models. In this paper, we proposed an ecohydraulic modeling framework that combines numerical methods and ecological theories to explore the dynamics and interplay between fluvial processes in rivers and the quality of physical habitat and density distribution for fish. The practicality of applying the developed system to ecohydraulics modeling was explored through three case studies and compared with as well as validated using observed data. On the basis of the calculated results, the model system was proven to be efficient in describing population dynamics of the European grayling (Thymallus thymallus. L.) in the Aare River in Switzerland. Satisfactory predictions of the long-term population evolution of the rainbow trout (Oncorhynchus mykiss), brown trout (Salmo trutta) and flannelmouth sucker (Catostomus latipinnis) in the Colorado River in the United States (US) were obtained. Furthermore, the effects of Da-Wei Power Plant construction on the Jiao-Mu River in China on the schizothorax (Schizothorax prenanti) and schizothorax (Racoma) fish species were investigated. The efficiency of fish stocking strategies was evaluated and optimal fish stocking numbers were proposed. The resulting ecohydraulic modeling framework provided very promising results, which highlighted the fundamental role of the temporal variability of hydro-morphological parameters in structuring populations of fish species. Using the ecohydraulic modeling framework to simulate population trends in anticipation of any changes in water management can provide decision-makers with valuable prediction results.

Water-system changes in swampy rice agro-ecosystems area and their economic impacts on farmers in South Sumatra, Indonesia

Conversion of land encompasses not only changes inthe use of land for cultivation of food to non-food product but also includes the conversion of land in use to unused land. Changes in the management of water in the area of agro-ecosystem in Ogan Komering Ilir (OKI) District has resulted in a change of use of paddy swampy land. Research was aimed :1) to analyze the differences in the income of farmers of rice due to the changes management water in the area of agro-ecosystems; and 2) to analyze the level of welfare of the rice farmers after adapting to the current environmental conditions. Research was carried out in the Belanti Village, Sirah Pulau Padang District, Ogan Komering Ilir District, South Sumatra Province, Indonesia. Location was selected purposively as the village was exposed to routine annual flood since 2008. The farmers has experinced crop and harvest failure, despite the fact that it has served as rice granary since 1992. As survey method with structured questionaires was applied in this research. Sampling was conducted purposively against 42 rice farmers who experienced crop failure. The primary and secondary data were collected and then subjected to land rent value analysis and t-test analysis. Results showed that: 1) changes in water management have reduced household income of farmers by 50.06%; and 2) the level of welfare of rice farmers is still low even though they have made adaptation efforts. To improve the quality of living for farmers affected by flooding, there is a need for integrated cooperation between the government of the country, palm plantation companies, and farmers.

Climate Change Adaptation Influences and Barriers Impacting the Asian Agricultural Industry

There has been an increasing interest among scholars regarding the impacts of climate change on agriculture and possible adaptation strategies for farmers. Little attention has been paid, however, to reviewing adaptation initiatives amongst farmers in Asia. This article fills this knowledge gap by examining the current literature on Asian farmers’ perception of climate change, their adaptation strategies, key factors influencing their choices, and the barriers to change. A systematic quantitative literature review is undertaken of 48 papers taken from a range of sources. The review indicates that farmers’ perceptions of climate change have been consistent with the scientific data. It further identifies farmers’ adaptation strategies with regards to soil conservation, water management and land use changes. The review shows numerous factors influencing, and barriers impacting, farmers’ ability to adapt. Influencing factors were analysed and categorised into five groups: cognitive, demographic, social-economic, resources, and institutional. Barriers hampering their adaptive capacity were identified as: a lack of access to information, a lack of access to extension services, limited awareness and knowledge, and limited financial options. The review finishes with some recommendations for future research.

Mapping CO2 fluxes of cypress swamp and marshes in the Greater Everglades using eddy covariance measurements and Landsat data

Wetlands play a critical role in the global carbon (C) budget by sequestering carbon dioxide (CO2) and storing significant amounts of C, but climate change is altering C dynamics in these ecosystems. Therefore, predicting and mapping net ecosystem exchange (NEE) of CO2 in wetlands has emerged as a focus of research to better understand where, how, and when biogeochemical cycles will be modified by human and natural disturbances like climate change. To address this, we developed an object-based machine learning ensemble approach to upscale eddy covariance (EC) CO2 flux measurements across two major wetland ecosystems (cypress swamp and freshwater marshes) in the Greater Everglades of south Florida. We linked 30-m Landsat, water depth, and air temperature data with EC flux measurements using the temporally composite concept for model development, and mapped fluxes within Big Cypress National Preserve (BCNP) and Everglades National Park (ENP) to characterize two distinct seasonal flux patterns. Using an ensemble analysis of three machine learning model outputs (Artificial Neural Network, Support Vector Machine, and Random Forest), our models of NEE at BCNP had a high predictive power with a R2 greater than 0.8, while NEE was predicted at ENP with a R2 greater than 0.5. We also generated an uncertainty map to quantify the prediction diversity caused by application of multiple models in upscaling. This uncertainty map identifies regions that are either easy or challenging to predict from model based analyses. We conclude that integration of Landsat, water depth, and air temperature data is valuable for quantifying CO2 exchange between the atmosphere and Everglades ecosystems, and the developed paradigm is promising for upscaling EC flux measurements in wetlands to study and mitigate disturbances to wetland ecosystem services such as hurricanes, fires, water management and/or climate change.

Producción, nutrientes, eutrofización y cianobacterias en Uruguay armando el rompecabezas

Despite there are multiple causes and consequences of eutrophication, this article analyses key aspects in the current context of Uruguay, emphasizing on cyanobacterial blooms as one of the most frequent and noticeable consequences. The worsening of eutrophication and its symptoms predicted with climate change, the keys for the reduction of diffuse losses of phosphorus with surface runoff on agricultural lands and the ongoing and future changes of water governance and management of the problem are some of the most important issues considered here. In this analysis, we also identify several challenges, both to fill knowledge gaps and in the arena of environmental management.

Water in Spain: paradigm changes in water policy

ABSTRACT This paper discusses the gradual eclipse of a water management paradigm governed by the dominance of hydropower and irrigation-driven development. With the advent of new values, the former approach has given way to an acknowledgement of the value of water for its intangible contribution to the landscape, among other things. The European Water Framework Directive has lent further impetus to changes in water management and governance. Future water authorities and stakeholders will face additional management challenges such as growing water scarcity, climate change and the predominant role of regional governments in water use negotiation and decision-making.

Vulnerability assessment of Sierra Nevada de Santa Marta, Colombia: World's most irreplaceable nature reserve

Sierra Nevada of Santa Marta (SNSM), Colombia, has been considered the world's most irreplaceable nature reserve. However, little is known about how human activities are generating significant impacts on this protected ecosystem. The aim of this work was to develop a Driver-Pressure-State-Impact-Response (DPSIR) framework as well as a threat assessment to obtain a generalized view regarding the environmental situation of the SNSM. According to the DPSIR approach, the main driving forces generating pressures on the SNSM are mining projects, water management, agricultural systems, tourism, territorial conflicts and climate change. These findings are in great agreement with the results. The multiple pressures derived from activities, such as mining, land use change, and tourism, have contributed significantly to the alteration of the homeostasis of the ecosystem and the reduction of the ecosystem services that it provides. As an important reserve area, different measures have been taken to protect biodiversity, however, their implementation has been insufficient. These results indicate it is a priority to establish governmental measures towards the conservation of SNSM, in particular sustainable development-based approaches involving local indigenous communities, as a guarantee for the well-being of the current and future generations.

Anthropogenic Drought: Definition, Challenges, and Opportunities

AbstractTraditional, mainstream definitions of drought describe it as deficit in water‐related variables or water‐dependent activities (e.g., precipitation, soil moisture, surface and groundwater storage, and irrigation) due to natural variabilities that are out of the control of local decision‐makers. Here, we argue that within coupled human‐water systems, drought must be defined and understood as a process as opposed to a product to help better frame and describe the complex and interrelated dynamics of both natural and human‐induced changes that define anthropogenic drought as a compound multidimensional and multiscale phenomenon, governed by the combination of natural water variability, climate change, human decisions and activities, and altered micro‐climate conditions due to changes in land and water management. This definition considers the full spectrum of dynamic feedbacks and processes (e.g., land‐atmosphere interactions and water and energy balance) within human‐nature systems that drive the development of anthropogenic drought. This process magnifies the water supply demand gap and can lead to water bankruptcy, which will become more rampant around the globe in the coming decades due to continuously growing water demands under compounding effects of climate change and global environmental degradation. This challenge has de facto implications for both short‐term and long‐term water resources planning and management, water governance, and policymaking. Herein, after a brief overview of the anthropogenic drought concept and its examples, we discuss existing research gaps and opportunities for better understanding, modeling, and management of this phenomenon.

Agency and governance in green infrastructure policy adoption and change

ABSTRACT Green Infrastructure (GI) is being adopted in cities all around the world as a key piece of climate change adaptation and water management for local governments. Recognizing that there is increasingly a diversity of actors engaged in designing, implementing, and fostering GI policies, we aim to better understand how urban GI policies take shape over time. We draw from two bodies of scholarship – – agency in Earth System Governance and entrepreneurs in public policy scholarship -- to study the agents who come to exercise authority to shape GI governance. We trace the trajectory of urban GI practices and policy over the past two decades, keenly observing how GI policies are adopted and change over time. We focus on Tucson, Arizona and combine document analysis, key informant interviews, and participation in stakeholder meetings with an innovative timeline method we collaboratively developed with stakeholders to identify the key events and actors in GI policy adoption. Our findings suggest diverse yet, interconnected roles for entrepreneurs highlighting how agency is exercised, how learning occurs and takes shape across entrepreneurs and scales, and how inequities are realized and addressed.

Assessing Future Impacts of Climate Change on Streamflow within the Alabama River Basin

Global climate change is expected to impact future precipitation and surface temperature trends and could alter local hydrologic systems. This study assessed the likely hydrologic responses and changes in streamflow due to future climate change within the Alabama River Basin (ARB) for the mid-21st century 2045 (“2030–2060”) and end-21st century 2075 (“2060–2090”). Using an integrated modeling approach, General Circulation Model (GCM) datasets; the Centre National de Recherches Météorologiques Climate Model 5 (CNRM-CM5), the Community Earth System Model, version 1–Biogeochemistry (CESM1- BGC.1), and the Hadley Centre Global Environment Model version 2 (HADGEM2-AO.1), under medium Representative Concentration Pathway (RCP) 4.5, and based on World Climate Research Program (WCRP)’s Couple Model Intercomparison Phase 5 (CMIP5), were assimilated into calibrated Soil and Water Assessment Tool (SWAT). Mann–Kendall and Theil Sen’s slope were used to assess the trends and magnitude of variability of the historical climate data used for setting up the model. The model calibration showed goodness of fit with minimum Nash–Sutcliffe Efficiency (NSE) coefficient values of 0.83 and Coefficient of Determination (R2) of 0.88 for the three gages within the ARB. Next, the research assessed changes in streamflow for the years 2045 and 2075 against that of the reference baseline year of 1980. The results indicate situations of likely increase and decrease in mean monthly streamflow discharge and increase in the frequency and variability in peak flows during the periods from the mid to end of the 21st century. Seasonally, monthly streamflow increases between 50% and 250% were found for spring and autumn months with decreases in summer months for 2045. Spring and summer months for 2075 resulted in increased monthly streamflow between 50% and 300%, while autumn and spring months experienced decreased streamflow. While the results are prone to inherent uncertainties in the downscaled GCM data used, the simulated dynamics in streamflow and water availability provide critical information for stakeholders to develop sustainable water management and climate change adaptation options for the ARB.

Alternative cropping systems for groundwater irrigation sustainability in the North China Plain

Over-exploitation of groundwater for agricultural irrigation has attracted worldwide attention because of the rapid groundwater depletion and environmental consequences induced by the current intensified cropping system. The combination of cropping system modeling with field experimentation is a powerful tool to evaluate the long-term consequences of changing water management and cropping systems under inter-annual climate variability. Here, we conducted two field experiments for early maize (EM, 2012–2018) single cropping system and winter wheat – summer maize (WWSM, 2015–2018) double cropping system in the North China Plain (NCP). Field observations were carried out for crop growth, yield, and soil volumetric moisture content (VMC) calibration with the Agricultural Policy/Environmental eXtender (APEX) model. The calibrated APEX model was used to assess the long-term (35 years, 1985–2019) impacts of EM and WWSM cropping systems under four irrigation scenarios on sustainable water and crop productivity using historical weather data. Results showed that the APEX replicated growth, yield, and VMC all reasonably well with R2 > 0.5, percent bias < 25%, and index of agreement > 0.8. The model realistically simulated VMC under full irrigation (FI), while model simulations under reduced irrigation were not that accurate. Neglectable yield losses of EM were observed by changing EM-FI to rainfed (EM-RF) (7.0 vs. 6.8 Mg ha−1) and lower inter-annual yield variability. Shifting WWSM-FI to EM-RF saved 47% evapotranspiration (ET) and 115% net water use (NWU) regardless of the precipitation category years, but caused 54% reduction in yield. Critical irrigation (CI) significantly reduced ET (7%) and NWU (28%) of WWSM, without yield loss, compared to FI, indicating great potentials of water-saving through optimized irrigation strategy. Minimum irrigation (MI) saved ET by 17% and NWU of WWSM by 62%, but led to 15% EY reduction compared with FI. In conclusion, the WWSM cropping system under CI has the potential to maintain yield with less water consumption, while rainfed EM is the best alternative option for mitigating groundwater over-exploitation with a certain extent risk in crop yield losses.

Effects of various driving factors on potential evapotranspiration trends over the main grain-production area of China while accounting for vegetation dynamics

Potential evapotranspiration (PET) is an important consideration in the study of agricultural water management and climate change. Although a number of studies have already explored the effects of climate factors on changes in PET, the quantitative effects of various driving factors needs to be further studied, as most studies have not accounted for vegetation dynamics by characterizing changes in leaf area and stomatal resistance. Here, we used the Shuttleworth–Wallace (S-W) model based on climate, vegetation, and energy factors to quantitatively analyze the effects of various driving factors at multiple spatial scales over the main grain-producing area of China (MGPAC) from 1982 to 2016. The S-W model had a satisfactory performance because S-W based Standardized Precipitation Evapotranspiration Index (SPEI) had a higher determination coefficient (0.33 VS. 0.26) than Penman-Monteith based SPEI for soil moisture standardized anomaly over MGPAC. MGPAC had a mean annual PET of 926.20 mm and showed a marked increase of 3.844 mm yr−1 during the study period. Evergreen broadleaf forest and grassland had the highest and lowest annual average PET values (1535.65 mm and 633.67 mm), respectively. Although climate factors could directly explain 79.42% of the PET increase over the MGPAC, vegetation dynamics were also identified to be a non-negligible factor explaining the increase in PET (directly explaining 18.91% of the PET trend). Specifically, vegetation dynamics contributed to explaining 67.30% and 48.91% of the PET trend in the Huang-Huai-Hai and Loess Plateau regions. These findings are closely related to changes in the temperature and leaf area index (LAI), which notably increased by 0.04 °C yr−1 (P < 0.01) and 0.0038 m2 m−2 yr−1 (P < 0.01), respectively. Regarding single drivers, variation in temperature and LAI significantly increased the PET by 3.582 mm yr−1 (P < 0.01) and 1.127 mm yr−1 (P < 0.01) across the MGPAC, respectively. This study can provide a new insight to improve agricultural production and management in China.

Groundwater resource exploration & development – Focus on groundwater to support surface water supply in the Lower Olifants River, South Africa

Many South-African towns in the Western Cape Province are dependent on surface water resources to satisfy the ever-increasing water demand. In recent years, the effects of climate change on the environment has challenged these areas continually and recently led to calls for major changes in water management. The Lower Olifants River Water Management Area experienced an extreme drought that persisted from 2016 to 2018, which led to the need for development of groundwater resources. The local economy of the Lower Olifants River is dependent on water releases from the Clanwilliam and Bulshoek Dams, located within the Olifants River Syncline (ORS), where ‘megafault’ zones form preferred flowpaths for groundwater in the Table Mountain Group (TMG) aquifers. The Lower Olifants River Water User Association (LORWUA) was mandated to proceed with the exploration and development of these aquifers to supplement the existing water use of the LORWUA. This will be available during periods of less rainfall and therefore increase the security of the water supplied. The groundwater project aimed at exploring and developing the fractured rock aquifers of the Peninsula (Op) and Skurweberg (Ss) Formations contained within the TMG. Through a high-level desktop assessment, remote sensing investigations and geophysical ground surveys, several target areas and drilling priorities were identified to obtain high borehole yields that access the resource in proximity to existing surface infrastructure. The projected water need from the groundwater resource was 8.6 million cubic metres per annum (Mm3/a). Faults/structure zones were the main hydrogeological targets, with drill target depths of structures planned for intersection deeper than 100 m below ground level (mbgl). Down-hole camera work and initial aquifer testing concluded that deep geological contact zones are prone to collapse when flow is induced in water-bearing fractures. This indicated the need for production borehole construction, even prior to aquifer testing for yield estimates. A major concern still to be resolved is the availability of water in storage and the realistic expectations of the well field over time. Although individual borehole testing provided information on the properties of specific water-bearing structures, long-term monitoring will provide a better understanding of the aquifer in response to abstraction and recovery in times of rest. The operating rules for the conjunctive use of the well field developed, with the existing surface water scheme, is still to be defined and modelled for optimisation, pending long-term monitoring.

Climate change and equitable urban water management: critical urban water zones (CUWZs) in Nepal and beyond

ABSTRACT Anthropogenic climate change is creating numerous challenges for rapidly urbanising countries. Foremost among these challenges is securing potable water for the urban population, while at times, mitigating flood risks. This article presents research on urban water issues in the rapidly growing city of Dhulikhel in Nepal within a global purview of climate change processes and impacts on urban water. The vulnerabilities to climate change are extremely high in Himalayan cities. New theoretical approaches are required to accurately define problems, causation and potential solutions. Our research has experimented with and developed the concept of Critical Urban Water Zones (CUWZs), which integrates vertical and horizontal elements of the physical environment with social, political and cultural considerations over time. CUWZ enables the identification of critical water management issues in local areas and provides a foundation for future urban water management policy and practices that are climate adaptive and equitable.

Effects of Thermal Water Upwelling on Microclimate Change in the High Geo-Temperature Roadway

Deep-circling thermal water upwelling and trickling to high geo-temperature roadway obviously alter the microclimate in mines, which brings difficulty to the prediction of airflow temperature and humidity. This is the basis of air-conditioning cooling load calculation. The heat and mass transfer between trickling water and airflow is rather complicated. Moreover, humid air exhibits the accumulation effect of heat and humidity in the long-distance flow process. In this paper, an apparatus was designed and developed to explore the influence of thermal water trickling on the airflow thermal parameters of a section of roadway (1L–39L, in which 1L–9L is the trickling section). The results show the following (1) With the rise of trickling water temperature, the total enthalpy difference of dry air in the roadway increases within a small range and that of humid air goes up nonlinearly. Besides, the increase of trickling water flow rate has an insignificant effect on the sensible heat of the airflow, while it plays a notable role in increasing the latent heat of the airflow. (2) High trickling water temperature results in a higher growth rate of humidity ratio at 19L than those at 29L and 39L in the early stage of thermal water trickling. Meanwhile, sensible heat exchange, which becomes strong after thermal water trickles for over 30 min, complicates the enthalpy difference variation rates of wet air at the three measuring points. (3) The three measuring points in the 19L–39L section all display a process of enthalpy growth with time. In the case of point 39L, the enthalpy difference of humid air surges sharply when the trickling water temperature is 80 ° C or the flow rate is 200 ml/min. The research results boast some reference value for thermal water management and microclimate change forecasting after the airflow passes through a trickling roadway.

Drought responses and adaptation strategies to climate change by pastoralists in the semi-arid area, Laikipia County, Kenya

This study was undertaken in Laikipia County, Kenya, to identify factors influencing the choices of strategies by pastoralists to adapt to climate change. The study particularly evaluates the role of perceived climate extremes (frequency of dry spells and droughts), early warning information, and access to private ranch grazing, in determining response decisions to climate change. Besides, we test if households jointly adopt climate change adaptation strategies. The primary data collected from 440 sample households was analyzed using the multivariate probit (MVP) model. In the MVP model, we consider the following measures: increased mobility (distance & frequency), storage/purchase of fodder, change in water management, partial shift to other livelihoods, and herd management. The results reveal that these adaptation strategies are jointly adopted by pastoralists as complements and substitutes. From the empirical result, the perceived increase in the number of dry spells and drought, access to early warning information, access to private ranch grazing, main market distance from homesteads, and the highest level of education in the household are the key determinants of the choices of adaptation strategies to cope with drought and climate change. From a policy perspective, this research contributes to the ongoing debate on best practices by addressing climate change-related challenges in semi-arid land management. Therefore, there is a need for early warning institutions to increase their visibility in the semi-arid areas by exploring effective methods of delivering climate risk information in good time. Improving access to market and private ranch grazing should be promoted in the Kenyan semi-arid areas. Given that pastoralists’ perceptions of climate change and climate risk is a decisive variable in adaptation decision-making, there is need to improve the understanding of pastoralists’ changing climatic conditions. Furthermore, since the results indicate that mobility and storage of fodder are substitutes, the adoption of hay production could become a key production strategy for pastoralists which will increase the competitiveness of their livestock in the market and increase milk production.