地表基质与植被覆盖空间错位是人工林地退化的重要原因,探究地表基质与植被覆盖的耦合关系,掌握不同地表基质物性结构异质性特征及其对植被生长的约束作用,对生态修复精准施策和植被恢复成效提升具有重要意义。渭北旱腰带位于黄河中游...地表基质与植被覆盖空间错位是人工林地退化的重要原因,探究地表基质与植被覆盖的耦合关系,掌握不同地表基质物性结构异质性特征及其对植被生长的约束作用,对生态修复精准施策和植被恢复成效提升具有重要意义。渭北旱腰带位于黄河中游黄土丘陵沟壑与关中平原的过渡区,是关中平原城市群北部的重要生态屏障。然而,受频繁的矿产资源开采活动影响,该区自然植被破坏严重。同时,在干旱气候、复杂地质和破碎地形的交织作用下,地表基质物性结构空间差异显著,不同地表基质类型水土保持功能参差不齐,导致植被恢复成效不均,生态系统脆弱性突出,严重制约了渭北旱腰带生态屏障功能的发挥。以黄河中游渭北旱腰带典型区域——陕西韩城地区为研究对象,基于地表基质剖面和植被生态样方综合调查,分析了不同地表基质物性结构异质性特征及其与上覆植被群落结构和根系构型的关系;结合植被生态指数时间序列,探讨了地表基质物性结构异质性对植被生态的影响。结果表明:泥质岩、碎屑岩夹泥质岩、冲洪积沙和碎屑岩地表基质的土壤发生层结构完整且厚度大,植被覆盖度均大于80%,2000~2023年植被净初级生产力(NPP)多年平均值相对较高,为378.01~430.77 kg C·m^(-2)·年^(-1),但受孔隙裂隙发育程度和深度的影响,植被群落结构存在差异;碳酸盐岩、冲洪积砾和花岗片麻岩地表基质植被覆盖度均小于50%,净初级生产力多年平均值也相对较低(156.21~320.04 kg C·m^(-2)·年^(-1)),其中花岗片麻岩地表基质裂隙过于发育(平均裂隙密度为4.73 m·m^(-2)),净初级生产力主要由稀疏的深根性乔木贡献,因此具有研究区最低的净初级生产力多年平均值(156.21 kg C·m^(-2)·年^(-1));风积物地表基质虽然土层深厚,但是因垂直节理发育,保水保肥能力弱,地表多生长灌木和草本,零星生长深根系耐旱乔木,净初级生产力多年平均值处于中等水平(378.29 kg C·m^(-2)·年^(-1))。植被覆盖度与地表基质表层土壤厚度间具有极显著的正相关关系(p<0.01),与宽度大于1 mm的裂隙密度之间也呈现显著的正相关关系(p<0.05),反映了地表基质物性结构(物质组成、空间结构、孔隙裂隙等)通过影响植被根系生长和水分吸收,决定了渭北旱腰带地表林草植被生长和净初级生产力水平。展开更多
To expand the study on the structures and biological activities of the anthracyclines anticancer drugs and reduce their toxic side effects,the new anthraquinone derivatives,9‑pyridylanthrahydrazone(9‑PAH)and 9,10‑bisp...To expand the study on the structures and biological activities of the anthracyclines anticancer drugs and reduce their toxic side effects,the new anthraquinone derivatives,9‑pyridylanthrahydrazone(9‑PAH)and 9,10‑bispyridylanthrahydrazone(9,10‑PAH)were designed and synthesized.Utilizing 9‑PAH and 9,10‑PAH as promising anticancer ligands,their respective copper complexes,namely[Cu(L1)Cl_(2)]Cl(1)and{[Cu_(4)(μ_(2)‑Cl)_(3)Cl_(4)(9,10‑PAH)_(2)(DMSO)_(2)]Cl_(2)}_(n)(2),were subsequently synthesized,where the new ligand L1 is formed by coupling two 9‑PAH ligands in the coordination reaction.The chemical and crystal structures of 1 and 2 were elucidated by IR,MS,elemental analysis,and single‑crystal X‑ray diffraction.Complex 1 forms a mononuclear structure.L1 coordinates with Cu through its three N atoms,together with two Cl atoms,to form a five‑coordinated square pyramidal geometry.Complex 2 constitutes a polymeric structure,wherein each structural unit centrosymmetrically encompasses two five‑coordinated binuclear copper complexes(Cu1,Cu2)of 9,10‑PAH,with similar square pyramidal geometry.A chlorine atom(Cl_(2)),located at the symmetry center,bridges Cu1 and Cu1A to connect the two binuclear copper structures.Meanwhile,the two five‑coordinated Cu2 atoms symmetrically bridge the adjacent structural units via one coordinated Cl atom,respectively,thus forming a 1D chain‑like polymeric structure.In vitro anticancer activity assessments revealed that 1 and 2 showed significant cytotoxicity even higher than cisplatin.Specifically,the IC_(50)values of 2 against HeLa‑229 and SK‑OV‑3 cancer cell lines were determined to be(5.92±0.32)μmol·L^(-1)and(6.48±0.39)μmol·L^(-1),respectively.2 could also block the proliferation of HeLa‑229 cells in S phase and significantly induce cell apoptosis.In addition,fluorescence quenching competition experiments suggested that 2 might interact with DNA by an intercalative binding mode,offering insights into its underlying anticancer mechanism.CCDC:2388918,1;2388919,2.展开更多
文摘地表基质与植被覆盖空间错位是人工林地退化的重要原因,探究地表基质与植被覆盖的耦合关系,掌握不同地表基质物性结构异质性特征及其对植被生长的约束作用,对生态修复精准施策和植被恢复成效提升具有重要意义。渭北旱腰带位于黄河中游黄土丘陵沟壑与关中平原的过渡区,是关中平原城市群北部的重要生态屏障。然而,受频繁的矿产资源开采活动影响,该区自然植被破坏严重。同时,在干旱气候、复杂地质和破碎地形的交织作用下,地表基质物性结构空间差异显著,不同地表基质类型水土保持功能参差不齐,导致植被恢复成效不均,生态系统脆弱性突出,严重制约了渭北旱腰带生态屏障功能的发挥。以黄河中游渭北旱腰带典型区域——陕西韩城地区为研究对象,基于地表基质剖面和植被生态样方综合调查,分析了不同地表基质物性结构异质性特征及其与上覆植被群落结构和根系构型的关系;结合植被生态指数时间序列,探讨了地表基质物性结构异质性对植被生态的影响。结果表明:泥质岩、碎屑岩夹泥质岩、冲洪积沙和碎屑岩地表基质的土壤发生层结构完整且厚度大,植被覆盖度均大于80%,2000~2023年植被净初级生产力(NPP)多年平均值相对较高,为378.01~430.77 kg C·m^(-2)·年^(-1),但受孔隙裂隙发育程度和深度的影响,植被群落结构存在差异;碳酸盐岩、冲洪积砾和花岗片麻岩地表基质植被覆盖度均小于50%,净初级生产力多年平均值也相对较低(156.21~320.04 kg C·m^(-2)·年^(-1)),其中花岗片麻岩地表基质裂隙过于发育(平均裂隙密度为4.73 m·m^(-2)),净初级生产力主要由稀疏的深根性乔木贡献,因此具有研究区最低的净初级生产力多年平均值(156.21 kg C·m^(-2)·年^(-1));风积物地表基质虽然土层深厚,但是因垂直节理发育,保水保肥能力弱,地表多生长灌木和草本,零星生长深根系耐旱乔木,净初级生产力多年平均值处于中等水平(378.29 kg C·m^(-2)·年^(-1))。植被覆盖度与地表基质表层土壤厚度间具有极显著的正相关关系(p<0.01),与宽度大于1 mm的裂隙密度之间也呈现显著的正相关关系(p<0.05),反映了地表基质物性结构(物质组成、空间结构、孔隙裂隙等)通过影响植被根系生长和水分吸收,决定了渭北旱腰带地表林草植被生长和净初级生产力水平。
文摘To expand the study on the structures and biological activities of the anthracyclines anticancer drugs and reduce their toxic side effects,the new anthraquinone derivatives,9‑pyridylanthrahydrazone(9‑PAH)and 9,10‑bispyridylanthrahydrazone(9,10‑PAH)were designed and synthesized.Utilizing 9‑PAH and 9,10‑PAH as promising anticancer ligands,their respective copper complexes,namely[Cu(L1)Cl_(2)]Cl(1)and{[Cu_(4)(μ_(2)‑Cl)_(3)Cl_(4)(9,10‑PAH)_(2)(DMSO)_(2)]Cl_(2)}_(n)(2),were subsequently synthesized,where the new ligand L1 is formed by coupling two 9‑PAH ligands in the coordination reaction.The chemical and crystal structures of 1 and 2 were elucidated by IR,MS,elemental analysis,and single‑crystal X‑ray diffraction.Complex 1 forms a mononuclear structure.L1 coordinates with Cu through its three N atoms,together with two Cl atoms,to form a five‑coordinated square pyramidal geometry.Complex 2 constitutes a polymeric structure,wherein each structural unit centrosymmetrically encompasses two five‑coordinated binuclear copper complexes(Cu1,Cu2)of 9,10‑PAH,with similar square pyramidal geometry.A chlorine atom(Cl_(2)),located at the symmetry center,bridges Cu1 and Cu1A to connect the two binuclear copper structures.Meanwhile,the two five‑coordinated Cu2 atoms symmetrically bridge the adjacent structural units via one coordinated Cl atom,respectively,thus forming a 1D chain‑like polymeric structure.In vitro anticancer activity assessments revealed that 1 and 2 showed significant cytotoxicity even higher than cisplatin.Specifically,the IC_(50)values of 2 against HeLa‑229 and SK‑OV‑3 cancer cell lines were determined to be(5.92±0.32)μmol·L^(-1)and(6.48±0.39)μmol·L^(-1),respectively.2 could also block the proliferation of HeLa‑229 cells in S phase and significantly induce cell apoptosis.In addition,fluorescence quenching competition experiments suggested that 2 might interact with DNA by an intercalative binding mode,offering insights into its underlying anticancer mechanism.CCDC:2388918,1;2388919,2.
