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Against the backdrop of rapid urbanization, there is a passive adaptation state shown in urban and rural ecological spaces. Due to the shrinking of ecological patches and the fracture of corridors, problems such as the obstruction of ecological processes, the decline of ecosystem services, and the loss of biodiversity occur. Considering that county ecological space is the key level to undertake provincial ecological security patterns and implement ecological demonstration projects, the construction of a county ecological infrastructure (EI) network is beneficial to the protection of regional ecological security, the improvement of the structures and functions of farmland ecosystems, and the enhancement of the quality of human settlements. In this study, taking Langzhong County in Sichuan Province as an example, a method path for an EI network construction was explored, and an optimization strategy for ecological patterns was proposed. Firstly, morphological spatial pattern analysis (MSPA) and a patch importance index were employed to identify ecological sources. Secondly, by constructing a landscape resistance surface and adopting a minimum cumulative resistance (MCR) model, potential EI corridor paths were extracted. Thirdly, the interaction force values between ecological sources were calculated with a gravity model and important ecological corridors were identified for priority protection and restoration. Finally, an EI corridor network was optimized by combining network structure indexes (α, β, and γ) with the field situation, and stepping stone patches and ecological breakpoints were identified. Based on the analysis results, an ecological protection pattern, which involved three vertical and two horizontal ecological belts, four ecological control zones, and six clusters of EI networks in Langzhong County, was put forward, aiming at protecting 50 ecological sources, repairing 105 ecological corridors of different grades, adding 9 stepping stone patches near long-distance corridors and 15 at the intersection of ecological corridors, and repairing 18 ecological breakpoints. This study has guiding significance for the optimization of county ecological patterns, the construction of farmland forest belts, and site selection of ecological restoration projects.

In recent years, the concept of sponge city has been applied in different places. There are also many experts on sponge cities who believe that to build a sponge city in the city, we need to improve and optimize the rainwater system. In this way, we can better explore the way to plan and design the stormwater system when conducting the construction of the sponge city. This paper will also analyze and study the characteristics and functions of rainwater system planning in the construction of sponge city, and also point out the difficulties of the city in the construction of sponge city. Nowadays, the city must make clear its optimization direction, methods and principles in the transformation of rainwater system, and the optimization and transformation of rainwater system can also improve the construction progress of sponge city faster. The optimization and application of rainwater system can lay a solid foundation for the construction of sponge city.

Two chickpea genotypes viz. Bhakar-2011 (desi) and Noor-2013 (kabuli) were sown in soil filled pots supplied with low (0.3 mg kg-1) and high (3 mg kg-1 soil) zinc (Zn) under control (70% water holding capacity and 25/20 °C day/night temperature), drought (35% water holding capacity) and heat (35/30 °C day/night temperature) stresses. Drought and heat stresses reduced rate of photosynthesis, photosystem II efficiency, plant growth and Zn uptake in chickpea. Low Zn supply exacerbated adverse effects of drought and heat stresses in chickpea, and caused reduction in plant biomass, carbon assimilation, antioxidant activity, impeded Zn uptake and enhanced oxidative damage. However, adequate Zn supply ameliorated adverse effect of drought and heat stresses in both chickpea types. The improvements were more in desi than kabuli type. Adequate Zn nutrition is crucial to augment growth of chickpea plants under high temperature and arid climatic conditions.

Abstract Deep carbon mitigation and water resources conservation are two interacted environmental challenges that China's power sector is facing. We investigate long-term transition pathways (2020–2050) of China's power sector under carbon neutrality target and water withdrawal constraint using an integrated capacity expansion and dispatch model: SWITCH-China. We find that achieving carbon neutrality before 2060 under moderate cost decline of renewables by 10–20% depends heavily on large scale deployment of coal-fired power generation with carbon capture and storage (CCS) since 2035 in China's water-deficient northwestern regions, which may incur significant water penalties in arid catchments. Introducing water withdrawal constraints at the secondary river basin level can reduce the reliance on coal-CCS power generation to achieve carbon neutrality, promote the application of air-cooling technology, and reallocate newly built coal power capacities from northwestern regions to northeastern and southern regions. If levelized cost of renewables can decline rapidly by about 70%, demand for coal power generation with CCS will be significantly reduced by more than 80% and solar photovoltaic (PV) and wind could account for about 70% of the national total power generation by 2050. The transition pathway under low-cost renewables also creates water conservation co-benefits of around 10 billion m3 annually compared to the reference scenario.

As an effective emission reduction approach, CO2 capture and storage (CCS) combined with enhanced water recovery (EWR) technology can not only reduce CO2 emissions, but can also recover deep saline water resources to relieve pressure on regional water resources, and can ensure the energy supply and both social and economic development. However, the environmental benefits and application costs of CCS-EWR are uncertain, and are determined by the technology level, geological conditions, and other physical factors. In this study, an optimal source-sink matching model and a techno-economic assessment model were developed to evaluate the contributions of CCS-EWR to carbon emission reduction and the increase of the water supply by considering various uncertain factors, as well as the corresponding costs. In addition, the Yellow River Basin (YRB) in China was selected as the research region because, while there are abundant coal-fired power plants (CFPPs) in the YRB, the water resources are scarce. The results revealed the following. (1) The maximum CO2 capture capacity of the 236 CFPPs in the YRB is about 738.77 Mt/a, and nearly 13.14 Gt of fresh water could be provided until the 236 CFPPs in the YRB retire, which can partially relieve the pressure on the supply of water resources. (2) With the consideration of the CCS-EWR benefits, the average cost of the 236 CFPPs in the YRB in their residual lifetime to reduce their CO2 emissions by 90% will be no more than 180 CNY/t. (3) The incentive effect of the increase of the industrial water price on the profits of CCS-EWR projects is not significant. CCS-EWR technology has better application prospects in China under the dual constraints of carbon-neutral targets and water shortages, and more policy support is required for its deployment.

AbstractRising atmospheric [CO2] and associated climate change are expected to modify primary productivity across a range of ecosystems globally. Increasing aridity is predicted to reduce grassland productivity, although rising [CO2] and associated increases in plant water use efficiency may partially offset the effect of drying on growth. Difficulties arise in predicting the direction and magnitude of future changes in ecosystem productivity, due to limited field experimentation investigating climate and CO2 interactions. We use repeat near‐surface digital photography to quantify the effects of water availability and experimentally manipulated elevated [CO2] (eCO2) on understorey live foliage cover and biomass over three growing seasons in a temperate grassy woodland in south‐eastern Australia. We hypothesised that (i) understorey herbaceous productivity is dependent upon soil water availability, and (ii) that eCO2 will increase productivity, with greatest stimulation occurring under conditions of low water availability. Soil volumetric water content (VWC) determined foliage cover and growth rates over the length of the growing season (August to March), with low VWC (<0.1 m3 m−3) reducing productivity. However, eCO2 did not increase herbaceous cover and biomass over the duration of the experiment, or mitigate the effects of low water availability on understorey growth rates and cover. Our findings suggest that projected increases in aridity in temperate woodlands are likely to lead to reduced understorey productivity, with little scope for eCO2 to offset these changes.

Abstract Aquatic centres are large and complex buildings which include at least one indoor swimming pool and several amenities such as gymnasium, cafe, office, spa, sauna and stadium. There are only a few studies that have investigated the energy and water use of aquatic centres. This study developed energy and water benchmarks for aquatic centres in Victoria, Australia using data from 22 aquatic centres. Statistical regression based benchmarking method was used to identify relevant correlations and significances of several variables in regards to the energy and water use of aquatic centres. The analysis indicated that conditioned usable floor area and the number of visitors have the strongest correlation and significance to the energy and water use of aquatic centres respectively. No strong correlation was found between energy and water use. The proposed energy benchmark for aquatic centres ranges between 648 kWh/m2 and 2283 kWh/m2 (conditioned usable floor area) and the proposed water benchmark for aquatic centres ranges between 11 L/Visitor and 110 L/Visitor. An attempt to identify energy and water efficient characteristics of aquatic centres was also undertaken using the detailed data collected.

Abstract Recent publications on the successful mineralisation of carbon dioxide in basalts in Iceland and Washington State, USA, have shown that mineral storage can be a serious alternative to more mainstream geologic carbon storage efforts to lock away permanently carbon dioxide. In this study we look at the pore solution chemistry and mineralogy of basaltic glass and crystalline basalt under post-injection conditions, i.e. after rise of the pH via matrix dissolution and the first phase of carbonate formation. Experimental findings indicate that further precipitation of carbonates under more alkaline conditions is highly dependent on the availability of divalent cations. If the pore water is deficient in divalent cations, smectites and/or zeolites will dominate the secondary mineralogy of the pore space, depending on the basalt matrix. At low carbonate alkalinity no additional secondary carbonates are expected to form meaning the remaining pore space is lost to secondary silicates, irrespective of the basalt matrix. At high carbonate alkalinity, some of this limited storage volume may additionally be occupied by dawsonite −if the Na concentration in the percolating groundwater (brine) is high. Using synthetic seawater as a proxy for the groundwater composition and thus furnishing considerable amounts of divalent cations to the carbonated solution, results in massive precipitation of calcite, magnesite, and other Ca/Mg-carbonates under already moderate carbonate alkalinity. More efficient use of the basaltic storage volume can thus be attained by promoting formation of secondary carbonates compared to the inevitable formation of secondary silicate phases at higher pH. This can be done by ensuring that the pore water does not become depleted in divalent cations, even after carbonate formation. Using seawater as carbonating fluid or injection of CO2 into the basaltic oceanic crust, where saline fluids percolate, can reach this goal. However, such an approach needs sophisticated reactive transport modelling to adjust CO2 injection rates in order to avoid too rapid carbonate deposition and clogging of the pore space too close to the injection well.