کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4375569 1617418 2016 13 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Forest soil carbon and nitrogen cycles under biomass harvest: Stability, transient response, and feedback
ترجمه فارسی عنوان
کربن خاک و کود نیتروژن جنگل تحت برداشت زیست توده: ثبات، پاسخ گذرا و بازخورد
کلمات کلیدی
برداشت محصول زیست توده؛ بهره وری استفاده از نیتروژن اکوسیستم؛ حداکثر عملکرد پایدار؛ مینرالیزاسیون بی حرکت سازی؛ بازخورد گیاه خاک
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک بوم شناسی، تکامل، رفتار و سامانه شناسی
چکیده انگلیسی


• A plant–soil carbon–nitrogen model is studied under biomass harvest.
• Harvest strategies influence plant–soil feedbacks through litter stoichiometry.
• A maximum ecosystem N use efficiency is found at intermediate rotation lengths.
• N use efficiency is increased by transient N retention through immobilization.

Biomass harvest generates an imbalance in forest carbon (C) and nitrogen (N) cycles and the nonlinear biogeochemical responses may have long-term consequences for soil fertility and sustainable management. We analyze these dynamics and characterize the impact of biomass harvest and N fertilization on soil biogeochemistry and ecosystem yield with an ecosystem model of intermediate complexity that couples plant and soil C and N cycles. Two harvest schemes are modeled: continuous harvest at low intensity and periodic clear-cut harvest. Continuously-harvested systems sustain N harvest at steady-state under net mineralization conditions, which depends on the C:N ratio and respiration rate of decomposers. Further, linear stability analysis reveals steady-state harvest regimes are associated with stable foci, indicating oscillations in C and N pools that decay with time after harvest. Modeled ecosystems under periodic clear-cut harvest operate in a limit-cycle with net mineralization on average. However, when N limitation is strong, soil C–N cycling switches between net immobilization and net mineralization through time. The model predicts an optimal rotation length associated with a maximum sustainable yield (MSY) and minimum external N losses. Through non-linear plant–soil feedbacks triggered by harvest, strong N limitation promotes short periods of immobilization and mineral N retention, which alter the relation between MSY and N losses. Rotational systems use N more efficiently than continuous systems with equivalent biomass yield as immobilization protects mineral N from leaching losses. These results highlight dynamic soil C–N cycle responses to harvest strategy that influence a range of functional characteristics, including N retention, leaching, and biomass yield.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Ecological Modelling - Volume 329, 10 June 2016, Pages 64–76
نویسندگان
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