| Phyllostachys edulis, which has many great characteristics such as fast growth, short-cycle, widely used, high economic value and so on, plays an important role in China bamboo species. However, with the rapidly development of bamboo industry and utilization, the problem of soil degradation is becoming more and more serious. Although fertilizer is widely used in production and operation to improve the quality of forest, the heavily use of fertilizers would be easily led to"diminishing returns"and environmental pollution. At present, the studies of control release fertilizer (CRF) have shown that it has high efficiency, light environmental stress and long-term in the fields of fruits, vegetables and precision agriculture, but rarely in moso bamboo forests. As a better material in shoots and wood, it would have a significant mean in phyllostachys edulis sustainable management, if CRF is reasonable used. According to the characteristics of moso bamboo, special slag fertilizer(SSF) which took the iron and steel smelting slag as the carrier and mixed with modifiers and macroelement was developed as a kind of CRF. In this paper, the methods of soil column leaching and the embedding in field were used to study the release rule, and two kinds of fertilization ways furrow and hole were chosen to reveal the effect on growth and soil quality in bamboo forest, the main conclusions are shown as follows:(1) SSF for bamboo had good property in slow release, and the release rate of tested fertilizers were followed by urea (Urea) > common compound fertilizer (CCF) > 1st Special slag fertilizer for moso bamboo (SSF-1) > Osmocote exact (OE). When soil column leaching method cultured fertilizers to 30 days, the accumulation release rates of N up to 89.98%, 80.67%, 49.84% and 42.16% respectively, which indicated that SSF-1 had achived the effecting of slow release under controlled conditions; On the second day embedding in field, the corresponding of release rates were 89.40%, 55.67%, 15.55% and 6.72%. When it reached 10 days, the release rates of CCF and Urea were more than 90%, while the SSF-1 and OE in 20 days were about 80%, and increased by a relatively long process. So, under the natural conditions, the release rates of N could be used to guide people to arrange their fertilization time and quantity.(2) SSF for bamboo can improve productivity of bamboo forest. The index of bamboo number, peak shoot number, shoot rate, bamboo rate, full-height, stem height and leaf N content were all increased significantly in different fertilization ways. As different distribution between furrow and hole, sensitivity to growth index, the number of shoots in furrows was 30.8% higher than that in holes, and rate of bamboo hole was significant higher than that of furrows 15.9%. The other indexes were not significant in the two ways, but in all, furrow was better.Under furrow application, SSF-1, SSF-2 and CCF had no significant differeces on the growth of bamboo, but the amount of bamboo shoots, bamboo amount of shoot rate, bamboo rate, youth bamboo DBH growth and leaves N content were highest for the implementation of SSF-1, SSF-2 and CCF lie in the center, and the last is CK; Height, stem high, ratio of trunk on the biomass were all appeared as CCF > SSF-1 > SSF-2 > CK.(3) The quality of soil had been improved releasing special slag fertilizer for moso bamboo, manifested as 0 ~ 40 cm layer of soil had large range of change, 40 ~ 60cm of soil was relatively stable. The soil bulk density presented downward trend with different methods that the average decline of furrow and hole were respectively 7.0 and 3.7 times as high as control. While the total porosity, average permeability, pH value, organic matter content, NPK content and urease content all presented upward trend and showed furrow > hole > CK. Comparison of SSF-1, SSF-2, and CCF on 0 ~ 60 cm soil layer under furrow condition showed that: soil pH value, total porosity and average permeability of water, organic matter, total N P K and available K were influenced greatestly by SSF-1, the average change amplitude were 1.83%, 4.45%, 6.41%, 1.74%, 2.10%, 0.59%, 3.50% and 4.49% respectively. While CCF had the greatest effect on soil bulk density, alkali-hydrolyzable N and soil urease, the average change amplitude were 1.87%, 2.85% and 3.74% respectively.(4) Comprehensive analysis indicated that the release rule of SSF was simliar to the OE ( 5 to 6 months ), and both of them could attain the aim of controlled-released and meet the needs of nutrient at differernt gorwth period. In all, SSF was more efficient, long-time, lasting, reducing pollution, so, it was the high efficient and economy fertilizer for the bamboo forest. |
