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Variation in leaf traits is critical for carbon gains and losses during leaf life and drives litter carbon and nutrient losses via decomposition. Accurately quantifying litter decomposition parameters is essential for assessing ecosystem carbon and nutrient dynamics. Leaf litterbags have commonly been employed to measure effects of environmental drivers, decomposers, and plant traits on decomposition rates. There has been much debate regarding the suitability of substituting senesced dead leaves with fresh (green) leaves in litterbags, which has been common practice for mimicking green leaf fall or for practical reasons. Therefore, we tested the null hypothesis that replacement of dead leaves with fresh leaves in litterbag experiments is justified, based on similarities in structural and chemical traits between fresh and dead leaves across plant species and growth forms.We conducted a paired litterbag decomposition experiment with both fresh and dead leaves of 26 common species in subtropical China, in each of five contrasting ecosystems.While fresh leaves generally decomposed faster than dead leaves, this deviation varied among species and growth forms, based on their traits. Overall, there was significant but rather weak correlation between dead leaf decomposition rate k and fresh leaf k, across species and ecosystem types; the deviation between fresh and dead leaf k was larger for fast‐decomposing, mostly herbaceous species. The different decomposition patterns for fresh versus dead leaves were underpinned by key underlying traits integrated in leaf resource economics spectra (LES) for fresh and dead leaves. The dead leaf LES exhibited a greater predictive capability for dead leaf k while the fresh leaf LES had higher explanatory value for the fresh leaf k values.Our findings partly reject the null hypothesis and ask for caution in inferring leaf litter decomposition rates based on green leaf litterbags or traits data. We suggest follow‐up research on substituting senesced roots and stems with fresh ones in decomposition experiments.Synthesis. Human activities and extreme weather events are leading to increasing pulse inputs of fresh plant parts and our study contributes to knowledge on how they contribute to overall decomposition rates besides senesced litter inputs. [ABSTRACT FROM AUTHOR]

Plant functional traits are increasingly used to understand ecological relationships and (changing) ecosystem functions. For understanding ecosystem‐level biogeochemistry, we need to understand how (much) traits co‐vary between different plant organs across species and its implications for litter decomposition. However, we do not know how the degree of synchronous variation in decomposition rates between organs across species could be influenced by different keystone invertebrates decomposing different senesced plant organs, especially in warm‐climate forests. Here we asked whether interspecific patterns in wood and leaf decomposition rates and in the spectra of resource economics traits underpinning them, co‐vary across woody species; and how (much) the keystone invertebrate decomposers of the litter of these organs enhance or lower such co‐variation of decomposition rates through time.We addressed these questions through an 18‐month 'common‐garden' decomposition experiment using leaf, twig and branch litter of 41 woody species in two distant subtropical forest sites in east China. We quantified the effects of leaf, twig and branch functional traits and their respective key invertebrates (moth larvae, termites) on the decomposition rates of those organs.Interspecific variation in wood traits was partly decoupled from that in leaf traits across species, while strong coupling was found between twigs and branches. The co‐variation between leaf and woody organ decomposition rates was altered dynamically through the shifting activities of the key decomposers, which created nonlinear relationships of invertebrate litter consumption as a function of species rankings along the resource economic trait spectra of leaves and branches.The deviations from coupling of decomposition rates between organs were likely caused by combinations of three mechanisms: (1) (de‐)coupling between organs of other traits, not commonly considered in resource economics spectra (e.g. resins) (2) leaf and wood decomposers having specific diet requirements and (3) temporal patterns of the decomposers' activity.Synthesis. Our study highlights the importance of considering the different ways by which invertebrate detritivores drive decomposition processes through time. Under the ongoing biodiversity decline, future research would benefit from a better understanding of the role of the dynamic interactions between detritivore activities and plant functional traits on the carbon turnover in ecosystems. [ABSTRACT FROM AUTHOR]

Foliar nitrogen (N) or phosphorus (P) status and their stoichiometric homeostasis are integral parts of the plant nutrient economy that determines the success of plant species in environments where N or P limits plant growth. Despite growing evidence for higher predictability of stoichiometric homeostasis of N (HN) than that of P (HP) on plant species abundance in temperate grasslands, no previous studies explicitly examined how foliar N and P status modulate the relationships between stoichiometric homeostasis and species distribution (regional species abundance) of woody plants, especially in P‐limited (sub)tropical ecosystems. We hypothesized that species with a conservative foliar nutrient status but a higher HP (but not HN) would be regional abundant in P‐limited forest.We measured foliar N (LNC) and P (LPC) contents of 54 woody species, community composition and soil N and P contents across 94 forest plots in Chinese subtropical forests. Then we evaluated the species' levels of N and P stoichiometric homeostasis and their regional abundance to test our hypotheses.HN and HP significantly increased with decreasing LNC and LPC. Foliar nutrient status positively correlated with the minimum values of both soil N and P contents, but only negatively associated with the maximum value of soil P content, indicating that conservative species can occupy a wider range of soil P‐ than N‐based nutrient niche. Meanwhile, species abundance negatively correlated with LNC and LPC, and positively correlated with HN and HP. However, the structure equation model analysis showed that species abundance increased with decline of LNC but not yet with increased HN. In contrast, species abundance enhanced with increased HP and decreased LPC via HP, rather than directly with a decline of LPC.Synthesis. This study provides empirical evidence that species with conservative foliar nutrient status are more stable in terms of N and P stoichiometric homeostasis, and foliar N and P economy modulate species abundance distribution in different ways. Our results suggest that maintaining strong stoichiometric homeostasis of leaf P, while maintaining conservative economy of N, is a key physiochemical mechanism for shaping species abundance distribution in P‐limited forests. [ABSTRACT FROM AUTHOR]

A hyper-branched hybridization chain reaction (HB-HCR) is presented herein, which consists of only six species that can metastably coexist until the introduction of an initiator DNA to trigger a cascade of hybridization events, leading to the self-sustained assembly of hyper-branched and nicked double-stranded DNA structures. The system can readily achieve ultrasensitive detection of target DNA. Moreover, the HB-HCR principle is successfully applied to construct three-input concatenated logic circuits with excellent specificity and extended to design a security-mimicking keypad lock system. Significantly, the HB-HCR-based keypad lock can alarm immediately if the "password" is incorrect. Overall, the proposed HB-HCR with high amplification efficiency is simple, homogeneous, fast, robust, and low-cost, and holds great promise in the development of biosensing, in the programmable assembly of DNA architectures, and in molecular logic operations. [ABSTRACT FROM AUTHOR]

In the title compound, C23H16Br2N2O2, intramolecular CH⋯Br and CH⋯N hydrogen bonds from the quinoline fragment form two five-membered rings. The quinoline ring system makes dihedral angles of 81.6 (2) and 31.2 (2)° with the phenyl rings of the diphenylacetamide fragment. In the crystal structure, molecules are linked into chains along the b axis by intermolecular CH⋯O hydrogen bonds. [ABSTRACT FROM AUTHOR]

There are two molecules in the asymmetric unit of the title compound, C21H15FN4O3. In the crystal structure, two intramolecular C— H⋯O hydrogen bonds form two five-membered rings. The molecules are linked into infinite chains along the b axis by intermolecular C--H⋯O hydrogen bonds, and further linked by C—-H⋯N interactions along the a axis. The packing is further stabilized by C—H⋯π interactions. [ABSTRACT FROM AUTHOR]

In the title compound, C16H15N3O2, the dihedral angle between the benzotriazole unit and the other benzene ring is 79.06 (1)°. The crystal structure is stabilized by C—H⋯π inter­actions and van der Waals forces. [ABSTRACT FROM AUTHOR]

In the title compound, C15H12FN3O, an intra­molecular C—H⋯F hydrogen bond forms a six-membered ring. Mol­ecules are linked into a tape along the b axis by an inter­molecular C—H⋯N hydrogen bond. The crystal packing is further stabilized by C—H⋯π and π–π inter­actions. [ABSTRACT FROM AUTHOR]

In the molecule of the title compound, C22H16FN3O3, intramolecular C—H...F hydrogen bonding results in the formation of a six-membered ring. In the crystal structure, intermolecular C—H...O hydrogen bonds link the molecules into centrosymmetric dimers. The packing is further stabilized by π–π interactions [centroid–centroid distance = 3.601 (2) Å]. [ABSTRACT FROM AUTHOR]

In the title compound, C22H14Cl2FN3O3, the two molecules in the asymmetric unit are linked into infinite chains along the a axis by intermolecular C—H...N and C—H...Cl hydrogen bonds. [ABSTRACT FROM AUTHOR]

In the molecule of the title compound, C15H12BrN3O, the dihedral angle between the benzotriazole ring system and the benzene ring is 19.0 (1)°. π–π interactions stabilize the crystal structure (centroid-to-centroid distances of 3.729 and 3.690 Å). [ABSTRACT FROM AUTHOR]

The title compound, C19H19BrN2O3, forms an intramolecular C—H...O hydrogen bond which results in the formation of a five-membered ring. In the crystal structure, intermolecular C—H...O hydrogen bonds link the molecules into infinite chains along the b axis. The packing is further stabilized by C—H...π and π-π interactions. [ABSTRACT FROM AUTHOR]

In the title compound, C16H15N3O, the whole skeleton of non-H atoms is approximately planar; the dihedral angle is 1.45 (2)° between the benzene and triazole rings in the benzotriazole unit and 6.46 (1)° between the other terminal benzene ring and the benzotriazole unit. The crystal structure is stabilized by C—H⋯π inter­actions. [ABSTRACT FROM AUTHOR]

In the title compound, C25H23N3O3, mol­ecules are linked into chains along the c axis by inter­molecular C—H⋯O hydrogen bonds. The packing is further stabilized by C—H⋯π and π–π inter­actions. [ABSTRACT FROM AUTHOR]

In the mol­ecule of the title compound, C23H17Cl2N3O3, the nearly planar benzotriazole system is oriented at dihedral angles of 19.53 (1) and 62.95 (1)°, respectively, with respect to the tolyl and dichloro­phenyl rings. In the crystal structure, mol­ecules are linked into chains along the a axis by inter­molecular C—H⋯O hydrogen bonds. [ABSTRACT FROM AUTHOR]

In the molecule of the title compound, C13H11N3O2, an intramolecular O—H⋯N hydrogen bond forms a six-membered ring. Intermolecular N—H⋯N hydrogen bonds connect adjacent molecules to form a zigzag chain parallel to the c axis. [ABSTRACT FROM AUTHOR]

In the molecule of the title compound, C16H14BrN3O, the benzotriazole ring system makes a dihedral angle of 62.1 (1)° with the benzene ring of the tolyl group. Weak π-π stacking interactions are observed between the triazole rings of inversion-related molecules, with a centroid-centroid distance of 3.726 (1) Å. [ABSTRACT FROM AUTHOR]

In the title compound, C17H13ClN6O, molecules are linked into a zigzag chain along the b axis by C—H…N hydrogen bonds. The packing is further stabilized by π-π interactions. [ABSTRACT FROM AUTHOR]

The molecules of the title compound, C21H14Cl2N4O3H2O, are linked into dimers by C—H… O hydrogen bonds and are linked into chains along the b axis by C—H…O and O—H…N hydrogen bonds involving the solvent water molecule. The packing is further stabilized by π-π interactions. [ABSTRACT FROM AUTHOR]

The asymmetric unit of the title compound, C15H13N3O2, contains two molecules. In the crystal structure, intermolecular N—H…O and N—H…N hydrogen bonds link the molecules, forming infinite chains along the a axis The packing is further stabilized by C—H…π interactions. [ABSTRACT FROM AUTHOR]

In the title compound, C12H9N5OS, mol­ecules are linked into chains along the b axis by N—H⋯N hydrogen bonds. The packing is further stabilized by C—H⋯π and π–π inter­acions. [ABSTRACT FROM AUTHOR]

Mol­ecules of the title compound, C10H8Cl2N4O, are linked into infinite chains along the c axis via O—H⋯N inter­molecular hydrogen bonds. The packing is further stabilized by π–π inter­actions involving the triazole rings. [ABSTRACT FROM AUTHOR]

The molecules of the title compound, C13H11N5O2, are linked into chains along the c axis by N—H…O and C—H…O hydrogen-bond contacts. N—H…N interactions connect the chains into two-dimensional layers. The packing is further stabilized by π-π interactions involving the purine system. [ABSTRACT FROM AUTHOR]

The molecule of the title compound, C22H16N2O2, lies on a crystallographically imposed center of symmetry at the midpoint of the C—C bond of the oxamide unit. In the crystal structure, intermolecular C—H…O and N—H…O hydrogen bonds link the molecules into ribbons along the c axis. The packing is further stabilized by C—H…π interactions. [ABSTRACT FROM AUTHOR]

In the title compound, C21H15ClN4O3, mol­ecules are linked into dimers by C—H⋯O hydrogen bonds and are linked into chains along the a axis by C—H⋯N inter­molecular hydrogen bonds. The packing is further stabilized by C—H⋯π and π–π inter­actions. [ABSTRACT FROM AUTHOR]

In the title compound, C12H13N3O2, the methoxyphenylpropanone unit is approximately planar. The dihedral angle between the benzene ring and the triazole ring is 80.60 (1)°. A—C HC—H⋯π interaction stabilizes the crystal structure. [ABSTRACT FROM AUTHOR]

In the title compound, [Zn(C13H12N2O)2(H2O)2](NO3)2, the ZnII ion is located on an inversion center. Each Zn center is six-coordinated by two O atoms and two N atoms from two benzamide ligands, and two O atoms from two water molecules, in a distorted octahedral geometry with normal values of Zn—N [2.1977 (19) Å] and Zn-O [2.0853 (17) and 2.1081 (18) Å] coordinating bonds. Intermolecular N—H⋯O and O—H⋯O hydrogen bonds link cations and anions into layers parallel to the bc plane. [ABSTRACT FROM AUTHOR]

In the centrosymmetric title compound, [Mn2(C4H2O4)-(NO3)2(C14H12N2)2(H2O)2], each Mn atom is six-coordinate in a distorted octahedral geometry. Molecules form stacks by π-π interactions (centroid-centroid distances of 3.826, 3.708 and 3.719 Å). The water molecules act as donors to form O—H⋯O hydrogen bonds. Moreover, the molecules are linked into chains along the a axis by C—H⋯O intermolecular hydrogen bonds. [ABSTRACT FROM AUTHOR]

In the molecule of the title compound, C15H12ClN3O, the dihedral angle between the benzotriazole ring system and the chlorobenzene ring is 63.06 (1)°.π−π Interactions stabilize the crystal structure. [ABSTRACT FROM AUTHOR]

In the title compound, C15H12FN3O, the dihedral angle between the benzotriazole fragment and the benzene ring is 19.0 (1)°. C—H…π interactions and van der Waals forces stabilize the crystal structure. [ABSTRACT FROM AUTHOR]

In the molecule of the title compound, C16H15N3O, the benzotriazole system is planar. In the crystal structure, intermolecular C—H…O hydrogen bonds link the molecules into chains. The packing is further stabilized by C—H…π interactions. [ABSTRACT FROM AUTHOR]

The title compound, C21H15FN4O3, has a nonplanar conformation. The mean plane of the benzotriazole group makes dihedral angles of 79.30 (1) and 11.64 (1)° with the pyridine and benzene rings, respectively. An intramolecular C—H...F hydrogen bond forms a six-membered ring. Molecules are linked into dimers by C—H...O hydrogen bonds, and are linked into chains along the b axis by intermolecular C—H...N hydrogen bonds. The packing is further stabilized by weak π–π interactions with a distance of 3.752 (2) Å between the centroids of the benzene rings. [ABSTRACT FROM AUTHOR]

In the molecule of the title compound, C21H15FN4O3, intramolecular C—H...O and C—H...F hydrogen bonds result in the formation of one six- and one five-membered ring. In the crystal structure, intermolecular C—H...O hydrogen bonds link the molecules into chains along the a axis. The packing is further stabilized by π–π interactions [centroid–centroid distance 3.632 (2) Å]. [ABSTRACT FROM AUTHOR]

The molecule of the title compound, C13H9Cl2N5OS2, is essentially non-planar, with a dihedral angle of 68.6 (2)° between the thiadiazole and triazole rings, and a dihedral angle of 62.8 (1)° between the thiadiazole and benzene rings. The crystal packing is stabilized by intermolecular C—H...N hydrogen bonds, which link dimers into zigzag chains along the b axis. [ABSTRACT FROM AUTHOR]

In the crystal structure of the title compound, C19H14N2O2, the molecules are almost planar. The dihedral angle between the two aromatic ring systems is 3.67 (1)°. [ABSTRACT FROM AUTHOR]

The mol­ecule of the title compound, C16H16N2O4, lies on a crystallographically imposed center of symmetry at the mid-point of the C—C bond of the oxamide unit. An intra­molecular C—H⋯O hydrogen bond forms a six-membered ring, and mol­ecules are linked into ribbons along the a axis by N—H⋯O hydrogen bonds. [ABSTRACT FROM AUTHOR]