Influences of leaf litter replacement on soil biochemical characteristics of main planted forests in Qinling Mountains of China

Abstract

Long-term continuous growth of the same tree species in planted pure forest will lead to soil polarization and degradation. Mixed forestation or litter replacement between different needle-and broad-leaved forests are effective measures, except fertilization, to control soil polarization according to the mutual compensation principle of different tree species. Through a two-year leaf litter replacement experiment in 4 typical planted pure forests of Larix kaempferi, Pinus tabulaeformis, Catalpa fargesii and Quercus aliena var. acuteserrata in Qinling Mountains of China, influences of leaf litter replacement on soil biochemical characteristics and their interspecific relationships were studied and main conclusions were reached as follows.(1) Annual leaf litter decomposition rate of broadleaved forests was 33.70% higher than those of needleleaved forests and increased by 8.35% -12.15% when needle-leaved litter was replaced with broad-leaved forests, whereas it decreased by 5.38% -9.49% when broad-leaved litter was replaced with needle-leaved forests.(2) Leaf litter replacement between needle-and broad-leaved forests popularly raised the contents of organic C, available N, P and K in soil, whose content increments in the needle-leaved forests (8.70% -35.84%) were obviously more than those in the broad-leaved forests (3.73% -10.44%), and in the former, the content increments after replacement with the litter of Catalpa fargesii (24.63% -35.84%) were more than those after replacement with the litter of Quercus aliena var. acuteserrata (8.70% -28.15%). Furthermore, the litter replacement was found to make the soil pH of needle-leaved forests developed from light-acid to neutral. (3) Litter replacement of the needleleaved forests with the broad-leaved litter popularly raised enzyme activities, amounts of microorganisms and contents of micro-biomass C and N in soil, the increments of which after replacement with the litter of Catalpa fargesii were also more than those after replacement with the litter of Quercus aliena var. acuteserrata; while the litter replacement of broad-leaved forests with needle-leaved litter resulted differently depending upon the tree species. Among them, the soil enzyme activities and contents of micro-biomass C and N in the forest of Quercus aliena var. acuteserrata raised while they lowered in the forest of Catalpa fargesii.

Phytoplankton and cyanobacteria abundances in mid‐21st century lakes depend strongly on future land use and climate projections

“…Catchment land use (agriculture and urban areas) is also a major influence on lake algal biomass (Allan, 2004; Carpenter et al, 1998; Jones et al, 2020; Soranno et al, 2015) and serves as a proxy for lakes’ altered nutrient concentrations (Foley et al, 2005; Vanni et al, 2011). Constructed forest areas may amplify eutrophication by increasing soil nutrient contents (Liu et al, 2008). However, high proportions of upstream forest and grassland areas prevent direct inflow of nutrients into freshwater lakes and can sustain water quality where anthropogenic activities are minor (Wiley et al, 2010).…”

Pervasive soil phosphorus losses in terrestrial ecosystems in China

“…Shandong Agricultural University (in Chinese with English abstract). Fu, G., Liu, Z., & Cui, F. (2008) Zhang, T., & Wu, W. (2002). Phosphorus sorption and release of paddy soils: effect of alternation of oxidized and reduced conditions.…”

Changes of Soil Microbiological Properties during Grass Litter Decomposition in Loess Hilly Region, China

“…Zhang et al (2018) showed that the litter decomposition rate is an important major factor affecting soil nutrient dynamics following afforestation [ 10 ]. Some studies have further shown that litter quality and quantity influenced both soil microbial biomass and enzyme activity [ 11 , 12 , 13 , 14 ], Hu et al (2005) found that the responses of soil microbiological properties to litter decomposition were much more sensitive than those of soil chemical properties [ 15 ]. Although these studies have been conducted in much detail, studies addressing the effects of different plant species on soil microbiological properties are relatively scarce.…”