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[Display omitted] • N V guarentee the evolution of O 2 to H 2 O 2 as O 2 exclusive adsorption sites, which improves the efficiency of photopurification work. • –CN, substitutes for hydrogens in primary amines, offer the opportunity for controlling reaction selectivity by inhibiting H 2 O 2 randomly decomposing to •OH. • The steric hindrance effect between N3C and SO induced by –CN and N V prevents H 2 O 2 reducing to •OH enabling the stable presence of SO. The key of photopurification, a bran-new technique for substance purification, is selective mineralization by surface modification of photocatalyst. CN/N V -PCN, nitrogen vacancies (N V) and cyano groups (–CN) co-modified polymeric carbon nitride (PCN), selectively photomineralize benzaldehyde (BZ) in industrial styrene oxide (SO) production solution. N V , special O 2 adsorption sites, guarantee the activation of O 2 to H 2 O 2. –CN, substitutes for hydrogens in terminal amines (–NH 2), inhibit H 2 O 2 randomly decomposing to •OH on –NH 2 sites. N V and –CN adjust the electronic distribution on triazine ring and H to reinforce π-π interaction and O···H N bond between PCN and SO, narrowing the space between benzene ring and N3C site, in which the steric hindrance effect hinders H 2 O 2 reducing to •OH by e- on N3C site. •OH can only produce at the adsorption sites of BZ, which results the selective mineralization of BZ. This work provides not only a modification method of PCN for selective oxidation reaction, but also a bran-new technique for removing homogeneous trace impurities in natural or industrial products. [ABSTRACT FROM AUTHOR]

• Introducing climate (CS) and vegetation seasonality (VS) into the Budyko framework. • CS and VS jointly contribute more than the changes in P and ET 0 in water partitioning. • In average the contributions of VS and CS in water partitioning are equally important. Climate and vegetation changes are main factors influencing water partitioning. However, their impacts on water partitioning are still not well understood. To revisit the interactions among climate, vegetation and water partitioning, this study introduces the climate seasonality (CS) and vegetation seasonality (VS) into the Budyko framework, by using a statistical approach combining the three-parameter Log-logistic probability distribution and multiple linear regression, based on the monthly 〈 P - ET 0 〉 (precipitation (P) minus potential evapotranspiration ( ET 0)) and Normalized Difference Vegetation Index (NDVI). This method is then validated and applied in 86 global catchments to quantify the contribution of climate and vegetation changes to evapotranspiration (ET). Results show that this model can predict well (mean R 2 = 0.81 ± 0.05, P < 0.05) the parameter n , a parameter reflecting the interactions between land surface and atmosphere in the Budyko framework. More importantly, CS and VS jointly control the variation in parameter n , and in average jointly contribute more (mean relative contribution of 57.1 ± 2.3 %) than the changes in P and ET 0 (mean of 42.9 ± 2.3%) to ET. These indicate that CS and VS are at least as important as the changes in P and ET 0 in affecting water balance. Furthermore, the VS contributes slightly lower (mean of 24.9 ± 0.3%) than the CS does (mean of 32.2 ± 2.3%), implying that CS and VS play comparable roles in water partitioning. These findings would be valuable for water resources management and assessing the impacts of climate and land surface changes on water balance in a gradually changing environment. [ABSTRACT FROM AUTHOR]

Carbon and water cycles in forest ecosystems are tightly coupled, but global warming-induced soil and atmospheric droughts alter the coupling, thereby greatly increasing uncertainty in predicting carbon and water cycles. Therefore, a carbon–water coupled model (TRIPLEX-CW-Flux) was developed, and an R package (rTRIPLEXCWFlux) was created to facilitate model application. TRIPLEX-CW-Flux integrates vapor pressure deficit and soil moisture into a stomatal conductance submodule to estimate forest carbon and water fluxes. Prediction accuracy of TRIPLEX-CW-Flux and rTRIPLEXCWFlux application were evaluated in a Chinese fir (Cunninghamia lanceolata) plantation. Simulated net ecosystem production (NEP) and evapotranspiration (ET) were in good agreement with flux observations (R 2 : 0.76 for NEP ; 0.71 for ET). Thus, the TRIPLEX-CW-Flux model can be used to predict and quantify effects of global warming-induced droughts on forest carbon and water cycles. The open-access rTRIPLEXCWFlux package facilitates estimations of carbon sequestration and water consumption in forest ecosystems using the observed flux data. • A physiological process model that couples carbon and water flux was developed. • Both atmospheric and soil drought stress were also integrated into the model. • An R package was encoded for the model to predict forest carbon and water flux. • The simulated values were comparable to the flux data observed in the forest. • This R package can be used to evaluate forest functions under climate change. [ABSTRACT FROM AUTHOR]

• GPP and ET were positively and linearly correlated to Rn and VPD in a karst forest. • WUE was negatively correlated to meteorological factors but positively to Bowen ratio. • WUE was not proportional to 1/VPD or 1/VPD0.5 but interactively responded to drivers. Water-use efficiency (WUE) is a key parameter that measures the balance between carbon gain and water loss in an ecosystem. Achieving better understanding of how WUE responds to environmental drivers is critical for revealing ecohydrological processes and mechanisms, and for biophysical modelling to investigate the interactions between vegetation and the changing environment. Karst landforms cover ∼10 % of the Earth's land surface; however, to date few studies have focused on the behaviours of WUE in karstic ecosystems. To fill these knowledge gaps, a two-year experiment was conducted to investigate the WUE and its drivers in a climax karst forest in southwestern China. Results showed that both the GPP (Gross Primary Production) and ET (evapotranspiration) showed exponential relationships to Ta (air temperature, P < 0.05), but linear relationships to Rn (net radiation, R 2 = 0.38 (GPP) and 0.78 (ET), P < 0.05) and VPD (water vapour pressure deficit, R 2 = 0.36 (GPP) and 0.28 (ET), P < 0.05), being quite different from those in other ecosystems. The reasons would be the different habits of the karstic plants, and the facts that the root zone water availability rarely dropped to low levels due to the frequent precipitation. The WUE, with the mean of 8.0 ± 4.8 mg CO 2 g−1 H 2 O, exhibited negative relationships to VPD (R 2 = 0.23, P < 0.05), Rn (R 2 = 0.28, P < 0.05), and Ta (air temperature, R 2 = 0.42, P < 0.05), and a positive linear relationship to the Bowen ratio (R 2 = 0.17, P < 0.05). Besides these, results also showed that the effects of a specific driver (e.g., VPD) on WUE was affected obviously by other factors (e.g., Ta, Rn), indicating that whether a driver is important or not to WUE, depends strongly on the environmental conditions. As the WUE-response formulas are often used to investigate and model the interactions between vegetation and environment, these findings suggested that the modelers should caution the versatility of the WUE-response formulas. [ABSTRACT FROM AUTHOR]