ABSTRACT Rice-Wheat rotation is the dominant land use in the state of Punjab, resulting in over exploitation of ground water resources. Thus, it is necessary to evaluate other land uses that requires less water and are sustainable. The present investigation was planned with four land uses viz., fallow (FLU), rice-wheat (ALU), grasses (GLU) and pear (PLU) with respect to their effect on soil organic carbon and soil physical characteristics in surface and subsurface depth in district Ludhiana, Punjab. The soil organic carbon (SOC) content was higher by 10, 30.9 and 24.9% under rice-wheat, grasses, and pear than that under fallow. The grasses showed higher soil moisture characteristics curve (SMCC) and lower bulk density (Db) than that under rice-wheat. The larger mean weight diameter (MWD) were observed under pear, grasses and fallow than that under rice-wheat by 0.21, 0.51 and 0.41 mm, respectively. The saturated hydraulic conductivity (Ks) was higher in magnitude by 56.1, 55.4 and 28%, respectively under PLU, GLU and FLU over ALU. Of the evaluated land uses, pear and grasses proved to be more sustainable by retaining more moisture, maintaining better soil physical characteristics and SOC under semiarid irrigated conditions in the state on long term gradual response.

中文翻译：

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半干旱灌溉条件下受土地利用影响的土壤有机碳和土壤物理特性

摘要 稻麦轮作是旁遮普邦的主要土地利用方式，导致地下水资源过度开发。因此，有必要评估需要较少水且可持续的其他土地用途。本调查计划使用四种土地用途，即休耕 (FLU)、稻麦 (ALU)、草 (GLU) 和梨 (PLU) 对土壤有机碳和地表和地下土壤物理特性的影响旁遮普省卢迪亚纳区的深度。稻麦、草、梨种植的土壤有机碳含量比休耕种植的土壤有机碳含量高10%、30.9%和24.9%。与水稻-小麦相比，禾草表现出更高的土壤水分特征曲线（SMCC）和更低的容重（Db）。在梨下观察到较大的平均重量直径（MWD），草和休耕分别比稻麦下高 0.21、0.51 和 0.41 毫米。在 PLU、GLU 和 FLU 下，饱和导水率 (Ks) 的量级分别比 ALU 高 56.1、55.4 和 28%。在评估的土地利用中，梨和草在该州半干旱灌溉条件下通过保持更多的水分、保持更好的土壤物理特性和 SOC 被证明是更可持续的。