Particulate organic carbon and nitrogen and soil‐test biological activity under grazed pastures and conservation land uses

Author:

Franzluebbers Alan J.1ORCID

Affiliation:

1. USDA–Agricultural Research Service Raleigh North Carolina USA

Abstract

AbstractSoil organic matter is assumed to accumulate with conservation management. On‐farm surveys using paired‐farm and chronosequence approaches could validate assumptions, as well as provide a diversity of soils and management conditions to assess organic matter fractions. The objective of this study was to assess how land use and pasture management affected the gradient of organic matter fractions from active to resistant. Particulate and non‐particulate (also called mineral‐associated) organic C and N fractions were isolated and soil‐test biological activity was measured from 304 profiles at 0‐ to 10‐, 10‐ to 30‐, and 30‐ to 60‐cm depths on 31 private farms in Virginia. Root‐zone enrichment contents of these soil properties were calculated following subtraction of a baseline from total stocks of each soil profile. Land use was a key factor affecting root‐zone enrichment (0‐ to 30‐cm depth) of particulate organic C (Mg C ha−1) (p ≤ 0.05): conventional‐till cropland (6.3) = no‐till cropland (9.2) < grassland (14.2) < woodland (16.7). Root‐zone enrichments of soil C and N fractions increased with pasture age to a plateau achieved by 25 years and were optimized at cattle stocking rate of 1.0 ± 0.2 Mg live weight ha−1. Feeding hay increased root‐zone enrichment of soil‐test biological activity (49 kg CO2‐C 3 day−1 [Mg hay]−1). Although non‐particulate organic C and N dominated, accumulation with time and steady‐state concentration of particulate fractions were vital steps toward greater soil organic matter under conservation management. Root‐zone enrichment calculations from on‐farm sampling were helpful in distinguishing true effects of management from pedogenesis on soil organic matter formation.

Funder

Foundation for Food and Agriculture Research

Agricultural Research Service

Publisher

Wiley

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3