|
| Effects of phosphorus addition on soil respiration component characteristics and carbon balance in dry farmlands of the Loess Plateau, Longzhong，China |
| Received:August 10, 2022 |
| View Full Text View/Add Comment Download reader |
| KeyWord:：phosphorus addition|soil respiration|carbon balance|soil enzyme|Loess Plateau |
| Author Name | Affiliation | E-mail | | GAN Run | College of Resources and Environmental Sciences, Gansu Agricultural University, Lanzhou 730070, China
State Key Laboratory of Aridland Crop Science, Gansu Agricultural University, Lanzhou 730070, China | | | QI Peng | College of Resources and Environmental Sciences, Gansu Agricultural University, Lanzhou 730070, China
State Key Laboratory of Aridland Crop Science, Gansu Agricultural University, Lanzhou 730070, China
Gansu Engineering Research Center for Agriculture Water-Saving, Lanzhou 730070, China | gsauqip@163.com | | GUO Gaowen | College of Resources and Environmental Sciences, Gansu Agricultural University, Lanzhou 730070, China
State Key Laboratory of Aridland Crop Science, Gansu Agricultural University, Lanzhou 730070, China | | | WANG Xiaojiao | College of Management, Gansu Agricultural University, Lanzhou 730070, China | | | CAI Liqun | College of Resources and Environmental Sciences, Gansu Agricultural University, Lanzhou 730070, China
State Key Laboratory of Aridland Crop Science, Gansu Agricultural University, Lanzhou 730070, China
Gansu Engineering Research Center for Agriculture Water-Saving, Lanzhou 730070, China | | | HAI Long | College of Resources and Environmental Sciences, Gansu Agricultural University, Lanzhou 730070, China | | | ZHANG Renzhi | College of Resources and Environmental Sciences, Gansu Agricultural University, Lanzhou 730070, China
State Key Laboratory of Aridland Crop Science, Gansu Agricultural University, Lanzhou 730070, China
Gansu Engineering Research Center for Agriculture Water-Saving, Lanzhou 730070, China | |
|
| Hits: 1713 |
| Download times: 1986 |
| Abstract: |
| The balance and sequestration of carbon in terrestrial ecosystems can be significantly affected by a large input of phosphorus. Here, we investigated dynamic changes in soil respiration and its components and the response of carbon balance to phosphorus addition in the dry farming areas of central Gansu Province. A completely randomized block design was used Dingxi city, with four levels of phosphorus application：no phosphorus（CK）, low phosphorus（P1）, medium phosphorus（P2）, and high phosphorus（P3）. Soil respiration, its components, and other environmental factors were measured in each treatment during the spring wheat growth period. The soil respiration temperature sensitivity index, net ecosystem productivity, and carbon balance were calculated. The results of the study showed that phosphorus addition increased the amount of CO2 emitted by soil respiration and its components. Compared with CK, the cumulative CO2 emissions of soil respiration increased significantly in the P1, P2, and P3 treatments by 13.85%, 24.86% and 26.47%, respectively（P<0.05）. Soil heterotrophic respiration increased significantly by 9.09%, 9.4%, and 14.52%（P<0.05）, while autotrophic respiration increased by 18.96%, 39.98%, and 38.33%, respectively（P<0.05）. Soil respiration and its components were affected by multiple factors, with fitting analysis showing that soil moisture and temperature accounted for 37.0%-49.7% and 69.4%-76.8% of the variation, respectively. Stepwise regression and variance decomposition showed that the main influences on soil respiration were alkaline phosphatase content in the 0-5 cm soil and 0-10 cm soil organic carbon layers. The main factors influencing soil heterotrophic respiration were 0-5 cm soil β-1, 4-glucosidase, 0-5 cm soil cellulose disaccharide hydrolase and 5-10 cm soil alkaline phosphatase. The main factors influencing soil autotrophic respiration were 0-5 cm soil alkaline phosphatase, 0-5 cm available phosphorus and 5-10 cm soil cellulose disaccharide hydrolase. All treatments showed a positive net ecosystem productivity, with values of 2 640.10 kg·hm-2, 3 412.91 kg·hm-2, 3 579.83 kg· hm-2, and 3 790.74 kg·hm-2 for CK, P1, P2, and P3 respectively. These values indicate that each treatment formed a ‘sink’of soil carbon. Therefore, in the management of dry farmland ecosystems on the Loess Plateau of Longzhong, the application of phosphorus fertilizer should be suitably increased（115 kg·hm-2 is recommended）to improve soil carbon sequestration efficiency and to build a scientific and rational modern agricultural production management system that places equal emphasis on environmental protection and economic efficiency. |
|
|
|
