ABSTRACT

Litterfall production, decomposition and nutrient release was investigated for three prominent agroforestry tree species, Prosopis cineraria, Tecomella undulata and Hardwickia binata, grown in the arid western region of India. The highest litterfall was recorded for H. binata (9.44 Mg ha^−l y⁻¹) followed by P. cineraria (8.94 Mg ha^−l y⁻¹) and T. undulata (3.74 Mg ha^−l y⁻¹). It took 15, 12 and 9 months for decomposition of 90% of the litter of H. binata, P. cineraria and T. undulata, respectively. Regression analysis showed that rainfall and air temperature had significant impacts on the decomposition process. Soil moisture and soil microbial biomass carbon showed high correlations (R² > 0.70, p < 0.01) with litter decay. The rate of release of N (k_N = 0.0014, surface (0–15 cm); k_N = 0.0015, sub-surface (15–30 cm)) and K (k_K = 0.0041, surface; k_K = 0.0047, sub-surface) was highest from P. cineraria, whereas release rates of P were statistically equivalent for all species. N release from the decomposing litter increased initially, but then decreased as decomposition progressed. Concentrations of P, K and Mg in the litter decreased throughout the decomposition, with some fluctuations in P and Mg for P. cineraria and H. binata at the later stage. Ca release did not follow any specific trend. P. cineraria, with considerable amounts of litterfall, the highest nutrient inputs to the soil and the most rapid release of nutrients during the decomposition, was concluded to facilitate greater fertility build-up of the soil compared with the other two species.

摘要

研究了生长在印度干旱西部地区的三种主要农林业树种Prosopis cineraria、Tecomella undulata和Hardwickia binata的凋落物产量、分解和养分释放。最高的凋落物记录为H. binata (9.44 Mg ha ^-l y ^-1 )，其次是P. cineraria (8.94 Mg ha ^-l y ^-1 ) 和T. undulata (3.74 Mg ha ^-l y ^-1 )。90% 的H. binata、 P. cineraria和T. undulata凋落物分别用了 15、12 和 9 个月的时间分解， 分别。回归分析表明，降雨和气温对分解过程有显着影响。土壤水分和土壤微生物生物量碳与凋落物腐烂具有高度相关性（ R ²  > 0.70，p < 0.01）。N ( k _N  = 0.0014, 表面 (0-15 cm); k _N  = 0.0015, 次表面 (15-30 cm)) 和 K ( k _K  = 0.0041, 表面; k _K  = 0.0047,地下）从P. cineraria中最高，而所有物种的 P 释放率在统计上是相等的。分解垫料中的 N 释放最初增加，但随后随着分解的进行而减少。凋落物中P、K和Mg的浓度在整个分解过程中下降，后期P. cineraria和H. binata的P和Mg有一些波动。Ca 释放没有遵循任何特定趋势。P. cineraria具有相当数量的凋落物、最高的土壤养分投入和在分解过程中最快速的养分释放，与其他两个物种相比，其结论是促进土壤肥力的增加。