{"title":"Biomass yield and nutrient removal by water hyacinth (Eichhornia crassipes) as influenced by harvesting frequency","authors":"K.R. Reddy, E.M. D'Angelo","doi":"10.1016/0144-4565(90)90045-L","DOIUrl":null,"url":null,"abstract":"<div><p>The effects of harvesting frequency on productivity, nutrient storage and uptake, and detritus accumulation by water hyacinth (<em>Eichhornia crassipes</em> /Mart/ Solms) cultured outdoors in nutrient-enriched waters were evaluated for a period of 13 months. Significant differences in hyacinth standing crop and productivity were measured with harvesting regimes of 1, 3 (harvest at maximum density) and 21 harvests over a 13-month period. The average plant standing crop decreased from 65 to 20 kg (fresh wt) m<sup>−2</sup> for systems with 1 and 21 harvests, respectively. Total harvested plant biomass was 67 kg (fresh wt) m<sup>−2</sup>, 110 kg (fresh wt) m<sup>−2</sup> and 162 kg (fresh wt) m<sup>−2</sup> for 1, 3 and 21 harvests, respectively. The mean net productivity increased from 7·7 to 16·5 and 24·5 g (dry wt) m<sup>−2</sup> day<sup>−1</sup> for 1, 3 and 21 harvests, respectively. Nutrient storage in water hyacinth biomass (live, dead and detrital) at the end of the study decreased from 93 to 46 and 30 g N m<sup>−2</sup>, and from 20 to 12 and 5 g P m<sup>−2</sup>, for 1, 3 and 21 harvests, respectively. For the system with one harvest, 46% of the stored N and 25% of the stored P were recovered in dedrital tissue at the bottom of the tank. For the systtem with 21 harvests, only 11% of the stored N and 15% of the stored P were recovered in detrital tissue at the bottom of the tank. Ammonium-N and soluble reactive P concentrations in the water column were significantly higher for the treatment with one harvest compared to the treatments with 3 and 21 harvests.</p></div>","PeriodicalId":100179,"journal":{"name":"Biomass","volume":"21 1","pages":"Pages 27-42"},"PeriodicalIF":0.0000,"publicationDate":"1990-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0144-4565(90)90045-L","citationCount":"36","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Biomass","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/014445659090045L","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 36
Abstract
The effects of harvesting frequency on productivity, nutrient storage and uptake, and detritus accumulation by water hyacinth (Eichhornia crassipes /Mart/ Solms) cultured outdoors in nutrient-enriched waters were evaluated for a period of 13 months. Significant differences in hyacinth standing crop and productivity were measured with harvesting regimes of 1, 3 (harvest at maximum density) and 21 harvests over a 13-month period. The average plant standing crop decreased from 65 to 20 kg (fresh wt) m−2 for systems with 1 and 21 harvests, respectively. Total harvested plant biomass was 67 kg (fresh wt) m−2, 110 kg (fresh wt) m−2 and 162 kg (fresh wt) m−2 for 1, 3 and 21 harvests, respectively. The mean net productivity increased from 7·7 to 16·5 and 24·5 g (dry wt) m−2 day−1 for 1, 3 and 21 harvests, respectively. Nutrient storage in water hyacinth biomass (live, dead and detrital) at the end of the study decreased from 93 to 46 and 30 g N m−2, and from 20 to 12 and 5 g P m−2, for 1, 3 and 21 harvests, respectively. For the system with one harvest, 46% of the stored N and 25% of the stored P were recovered in dedrital tissue at the bottom of the tank. For the systtem with 21 harvests, only 11% of the stored N and 15% of the stored P were recovered in detrital tissue at the bottom of the tank. Ammonium-N and soluble reactive P concentrations in the water column were significantly higher for the treatment with one harvest compared to the treatments with 3 and 21 harvests.
在13个月的试验中,研究了采收频率对富营养化水体中室外养殖水葫芦(Eichhornia crassipes /Mart/ Solms)生产力、养分储存和吸收以及碎屑积累的影响。在13个月的采收期内,采用1次、3次(最大密度采收)和21次采收制度,测量了风信子立木产量和生产力的显著差异。在收获1次和21次的系统中,平均直立作物从65 kg(新鲜wt) m - 2减少到20 kg(新鲜wt) m - 2。收获的总植物生物量分别为67公斤(新鲜重量)m - 2、110公斤(新鲜重量)m - 2和162公斤(新鲜重量)m - 2。在第1、3和21个收获期,平均净生产力分别从7·7增加到16·5和24·5 g(干重量)m−2 day−1。研究结束时,水葫芦生物量(活的、死的和碎屑)的营养储量分别从93 g N m−2下降到46 g和30 g,从20 g P m−2下降到12 g和5 g。对于一次收获的系统,46%的储存N和25%的储存P在罐底的脱皮组织中被回收。对于收获21次的系统,只有11%的储存氮和15%的储存磷在罐底的碎屑组织中被回收。1次收获处理的水柱中铵态氮和可溶性活性磷浓度显著高于3次和21次收获处理。