【摘 要】
:
We collected soil samples from two representative sites at Aatmile of Khagarachari hill district in Chittagong Hill Tracts. One of the sites was under shifting
【机 构】
:
Institute of Forestry and Environmental Sciences,Department of Microbiology,Department of Applied Ph
论文部分内容阅读
We collected soil samples from two representative sites at Aatmile of Khagarachari hill district in Chittagong Hill Tracts. One of the sites was under shifting cultivation and the other an adjacent 13-year old teak plantation. Both sites were in the same physiographic condition and same aspect with parable soil type, which enabled us to measure the effects of shifting cultivation on soil micro-flora. We studied soil phys-ico-chemical properties and the biochemical and biological properties of soil microbes. Moisture and organic matter content as well as fungi and bacterial populations, both in surface and subsurface soils, were signifi-cantly (p≤0.001) lower in shifting cultivated soils compared to soils not under shifting cultivation, i.e. the teak plantation site. The most abundant bacteria in surface (0-10 cm) and sub-surface (10-20 cm) soils under shifting cultivation were Pseudomonas diminuta and Shigella, respec-tively, while in corresponding soil layers of teak plantation, predominant microbes were Bacillus firmus (0-10 cm) and Xanthomonas (10-20 cm). The microbial population differences cannot be explained by soil texture differences because of the textural similarity in soils from the two sites but could be related to the significantly lower moisture and organic mat-ter contents in soils under shifting cultivation.
其他文献
采用溶胶-凝胶法在不同基体表面制备了叠层式TiO2/SnO2复合纳米薄膜。用扫描电子显微镜(SEM)、X射线衍射(XRD)对复合薄膜表面形貌和晶体结构进行表征。采用紫外-可见吸收光谱
文章报道了塔里木河中游胡杨林土壤原生动物的种类组成、优势类群、相似性系数等,与中国典型地带土壤原生动物进行比较.结果共观察到原生动物5个纲7个目13个属17个种.
We studied relations between natural seedling reproduction and above ground environment in a longleaf pine ecosystem. Forty-eight 0.05 ha circular plots were sa
From March 2007 to March 2009 we quantified plant diversity at Chilapatta Reserve Forest in Terai Duars in the Indian eastern Himala-yas. We sampled stratified
Siberian Pine (Pinus sibirica) is an ecologically and eco-nomically important species in pristine forests throughout northern Rus-sia. Four provenances of P. si
We investigated the effect of forest thinning on soil nitrogen mineralization, nitrification and transformation in a Cryptomeria japoni-ca plantation at high el
We investigated the effect of fire disturbance on short-term soil respiration in birch (Betula platyphylla Suk.) and larch (Larix gmelinii Rupr.) forests in Gre
Cropland agroforest is an important production system in the southwest region of Bangladesh. This study focused on the floristic composition and management of e
Understanding the age effect on soil carbon balance in forest ecosystems is important for other material cycles and forest management. In this research we investigated soil organic carbon density, lit
本文提出了一种由PLC(可编程控制器)为主体的火灾自动探测报警控制器。将来自探测器和手动报警按钮的信号输入到PLC,经PLC逻辑判断,输出报警信号和启动自动灭火系统信号。由于PLC