Advanced Materials Research Vols. 518-523

Abstract: Poyang Lake Ecological Economic Zone has large forest area, so it's very important to construct prevention forest fire disaster system. This paper presents an algorithm for prevention forest fire disaster based on digital image processing technology. The algorithm distinguishes the realtime forest video by smoke and fire. To determine whether there are some suspicious area in the image in the spatial domain by judging the color properties of smoke and fire through Clustering Algorithm. If it detects any suspicious circumstances, then fixes ccd and detects the suspicious areas in the time domain. In this step, firstly get the initial detect results by wavelet decomposition , then use the k-means clustering algorithm for the spread detection of smoke. Experimental results show that the algorithm is ideal for the experimental video. It alarms before the fire disaster occurs to avoid major fire disaster, which protects the forest resources in the Poyang Lake Ecological Economic Zone.

Abstract: The dynamics of vegetation cover plays an important role in global environment evaluation. Due to the spatial, spectral and radiometric differences among different remote sensing platforms, building long-term and consistent vegetation index (VI) time series is desired to derive comparable vegetation health. In this paper, an approach called Min_Max stretch transformation (MMST) was proposed to generate long-term and consistent VI series based on spatio-temporal association analysis between AVHRR NDVI and MODIS EVI. The proposed approach intended to map AVHRR NDVI to MODIS EVI level and thus both VI products provided consistent VI series. The consistency of the transformed dataset was further evaluated.

Abstract: To explore why seed germination rate is very low for autotetraploid of Robinia pseudoacacia (ARP), the developmental process and matured structure of its ovule were studied by paraffin section and structure anatomy in this paper. Ovule development and abortion of ARP can be formally divided into 3 stages. The initial stage occurred from 5th to 30th day after coronal opened up wholly; in this stage, zygotes were dormant, weight and transverse diameter of ovule increased slower, the rate of ovule with embryo was 0%, and the average abortion rate of ovule was 51.9%. The middle stage went through from 30th to 50th day after coronal opened up wholly; during this stage spherical embryo and heart-shaped embryo were observed, embryo and endosperm grew fast, weight of ovule increased rapidly, aborted ovules had yellow-transparent liquid around them, the rate of ovule with embryo was 33.2%, and the average abortion rate of ovule was 30.2%. The later stage came up from 50th day after coronal opened up wholly to ovule maturation, during this stage cotyledonary embryo formed gradually, the average rate of ovule with embryo was 70.8%, and the average abortion rate of ovule was 72.6%. The percentage of three parts (embryo, endosperm and integument) of ARP matured ovule varied obviously compared with matured ovule of diploid Robinia pseudoacacia, for which ARP matured ovules aborted severely. Therefore, the abortion of ARP ovules was the direct reasons why its seeds aborted.

Abstract: based on the investigation of afforestation project in 2007 in Pingluo city of Ningxa province, this paper analyzed the change of salt concentration of soil and the planting survival rate, and then proposed the afforestation techniques system for saline-alkaline soil in northern Ningxia. The result showed that: (1) Under application of organic fertilizer and irrigation water to reduce salt concentration in the soil, the salt concentration of the soil depths of 10 cm to 30 cm and 30 cm to 50 cm were (1.37 g/l), and the planting surviving rates for Tamarix chinensis, Amorpha fruticosa, Elaeagnus angustifolia, and Populus euphratica were 75%, 75.4%, 96.8% and 92.6% respectively. But with the film covering on the bottom of the planting hole and irrigating water to reducing salt, the salt concentrations for the two soil depths were all 1.28g/l, and the planting surviving rate of D was only 11.4%. (2) Under elevating the planting surface and increasing the soil depth by 80 cm to 100 cm with the soil from trench, and application of organic fertilizer and irrigation water to reducing salt, the salt concentrations for two depth layers were around 0.36g/l, and the planting surviving rates of Elaeagnus angustifolia, Sophora japonica, Tamarix chinensis, and Amorpha fruticosa were 84/1%, 91.1％, 99.5%, and 82.5% respectively. But when soil depth was increased by 40cm to 60cm, the salt concentrations were between 0.65g/l to 0.71g/l, and the planting surviving rates for Amorpha fruticosa, Tamarix chinensis, Elaeagnus angustifolia, Sophora japonica, Euonymus bungeanus were 81.2%, 64.3%, 93.6%, 83.8%, and 100% respectively. (3) Afforestation is a kind of systemic project, if planting is based on selecting some salt resistance tree species such as Amorpha fruticosa, Tamarix chinensis, Elaeagnus angustifolia, Populus euphratica, Atriplex canescens, Nitraria sibirica, Hippophae rhamnoides, Lycium chinense, Sophora japonica, Euonymus bungeanus etc. with the techniques of elevating the planting surface and increasing the soil depth, covering film on the bottom of planting hole, ground surface covering and seedling treatment with chemicals, and application of organic fertilizer, soil amending chemicals and irrigation water to reduce salt, the planting survival rates will be increased in salt-alkaline soil in northern Ningxia.

Abstract: With the development of the world, public demands for recreation opportunities and scenic beauty of forest have risen substantially in recent decades. Providing recreation activities is one of most important function of forest. The Scenic Beauty Model was established to predict landscape quality, the results were obtained by using Quantification Theory Type I for multiple regression models. The variables in the model of contribution rate can be seen, shrub coverage has the greatest influence in landscape quality, the following variables were canopy density, average height of first alive branches, noticeability of dead branch et al. Then management measures were put forward. It is important for managers in better understanding the interactions between scenic beauty and other forest attributes, has an important role in construction of scenic and recreational forest.

Abstract: Palm plants are important garden plant resources, in the landscape has many USES. Based on the observation of the landscape of hainan palm, palm plants in hainan explore into the main application of way and configuration types, and points out that the palm species of plant landscape in hainan shortage, and puts forward personal advice.

Abstract: Through the experiment of different Irrigation Amounts with urea applied, the paper studied the influence of Irrigation Amounts on soil nitric nitrogen dynamical changes under film hole irrigation and the nitric nitrogen content of the growing period was determined. The result showed: different irrigation amount in the profiles being 3cm and 8cm away from the film hole center, it appeared nitric nitrogen accumulation peaks, increased the irrigation amount promoted the transformation of urea, increased the transformed nitric nitrogen content and distribution of nitric nitrate and the risk of nitric nitrate leaching. In the profiles being 3cm away from the film hole center, the nitric nitrogen accumulation peak significantly reduced at harvest stage, but it reduced in the profiles being 8cm away from the film hole center at milky stage. The milky stage was the maximum period when the corn uptook nitrogen at different irrigation amount. Increased irrigation amount lower the accumulation content of nitric nitrogen near the film hole center after harvest, and higher the accumulation content of nitric nitrogen far away from the film hole center. Above researches could provide the basis for rational fertilization of farmland and nitrate environmental impacts on assessment.

Abstract: Stoichiometric characteristics of soil organic carbon (SOC), total nitrogen (N) and total phosphorus (P) across forest communities were investigated based on community classification in Changtan Nature Reserve, Guangdong province, China. Results are as follows: (1) the monsoon broadleaved forest had high concentrations of SOC, N and P as compared with other community types. The highest concentration of SOC (39.2±2.3 g•kg-1) was found in the Schima superba community, while the highest concentration of N (2.21±0.24 g•kg-1) occurred in the Castanopsis fissa community, which also had the highest P concentration. Pinus massoniana community had the lowest concentrations of SOC, N, and P, especially lacking in P element. (2) Communities which had longer succession time exhibited a high C:P ratio. The Schima superba and Castanopsis fissa communities had the highest C:P ratios (301.0 and 304.2, respectively); in contrast, soil C:P ratio in the Cunninghamia lanceolata community was only 150.0. (3) The highest and lowest ratios of soil C:N were found in monsoon evergreen broadleaved forest (36.6) and Schima superba community (17.0), respectively, which was significantly different (P < 0.05). No significant difference was found in the N:P ratios among the five communities.

Abstract: Flora composition and species diversity features of Pseudolarix amabilis community at the Yaoluoping natural reserve in Anhui Province were analyzed. According to the statistics from 4 sample plots, there are 88 species (including varieties) of 77 genus belonging to 48 families of vascular plants. There are various plants in the community of Pseudolarix amabilis, and its family and genus are of scattered composition. Their floral composition is complicated. In terms of geographical composition of seed plant genus, most of them are distributed in the temperate zone. The species diversity of shrub layer is the highest, the tree layer is the second, and the herb layer is the lowest in the vertical structure of the community. The species diversity index of different layers shows: shrub layer>tree layer>herb layer.

Abstract: This paper, based on the long sequence meteorological data and the MODIS remote sensing data, calculates the every-ten-day NDVI index and SPI index of the grassland vegetation in the Eastern Inner Mongolia between 2006 and 2010. It applies the SPI index to indicate the degree of drought and the NDVI index to represent the growth status of the grassland vegetation. This paper analyzes the relationship between the NDVI index and the SPI index by the Time Series Spectrum Analysis Method, leading to the conclusion that the vegetations are sensitive to the drought in the green-turning and yellowing period, but relatively not that sensitive in the budding and maturation period, and that, the vegetations in meadow grassland, typical grassland and desert grassland vary in the responses to the drought.