The Ecological Services And Sustainable Management Of The Main Shrubs In The Hill Areas Of South Taihang Mountains

Shrubs forest as the main secondary vegetation in hilly areas ofsouthern Taihang Mountain, is of great significance for the maintenance of theecological environment. In particular, the implementation of the Taihang Mountaingreening project in recent years, many forests produce, but as a major local vegetationshrub in the ecological construction is often ignored, which is a serious impact on theecological restoration and reconstruction of local vegetation. Therefore, to carry outthe value evaluation of shrubs forest ecosystem services in the areas, especially for thedivision of the different types of shrubs forest, is very necessary and provides atheoretical basis and reference for classification management, ecologicalcompensation benefits. In this paper, based on the classification of the main shrubsinculding Vitex negundo L. var, Ziziphus jujuba var, Gleditsia hetero-phyiia Bunge,through observation and monitoring, according to "specifications for assessment offorest ecosystem services", the ecological services of water conservation, Soilconservation, Carbon fixation and oxygen release, nutrients accumulation, biologicaldiversity conservation are calculated and evaluated. and the management andutilization of shrubs forest are studied, which provide scientific basis for thesustainable management and ecological compensation. The results show that:1）Acorrding to existing research results, combined with the actual, the typesclassification system dominated by shrubs species’s individual, population andcommunity characteristics, includes of the average height of shrubs, shrubs densityand the important value and the shrubs community diversity of Shannon-Wienerindex and Pielou evenness index (Jsw). the Vitex negundo shrub forest is divided into4types, jujube and Gleditsia hetero-phyiia Bunge shrubs were divided into3types. Atrue reflection of the shrubs spatial heterogeneity, which greatly reduces the numberof shrubs forest types, and satisfies the need of ecologial services value assessment ofspatial heterogeneity;2) the studies of the main shrubs soil physical properties show that: The averagevalues of soil thickness of Vitex negundo L. var, Ziziphus jujuba var, Gleditsiahetero-phyiia Bunge shrubs in different types were between28.38-54.11cm,21.35-53.57cm,15.49-40.92cm; the silt and clay content of0-20cm layer are between17.42-31.47%,6.27-20.78%,20-40cm were14.44-23.93%,5.37-16.46%; soil bulk density between1.09-1.31; soil total porosity is between48.49%-60.81%, the noncapillary porosity between11.87-21.26%. Shrubs can improve soil structure, wich isconducive to ecological benefit;3) The studies of soil chemical properties show that: the soil organic mattercontent in0-20cm is between0.86-3.43%, significant difference. The coefficientvariation is between10.40-71.70%; soil nutrients N, P, K content in0-20cm isbetween0.063-0.23%,0.021-0.080%,1.3-1.64%. The20-40cm content is lower thanthe surface. Soil organic matter and nutrients content of20-40cm is lower than that of0-20cm, the material exchange is less between soil layers, soil erosion willsignificantly change soil nutrient status, that is not conducive to the ecologicalrestoration and reconstruction;4)The shrub water holding characteristic research shows that: The canopyrainfall interception rate averaged Vitex negundo L. var33.12%, Ziziphus jujuba var24.91%, Gleditsia hetero-phyiia Bunge25.81%, The canopy rainfall interception ofthree shrubs forest is in0.25mm-0.66mm; the rainfall interception of litter changerange of0.65mm to2.16mm. The rules are as follows: the community compositionfrom simple to complex, site conditions from the poor to good, the rainfallinterception of forests litter changes from small to big; The soil water holdingcapacity of three shrubs forest was513.6mm,554.7mm,343.4mm, interspecificvariation with community structure by the simple to the complex, which showed anincreasing trend; Ziziphus jujuba var was1.62times of Gleditsia hetero-phyiia Bunge;The maximum and minimum values of soil thickness is54.11cm and15.49cm, nearly4times;5) Studies on hydrological characteristics show that: The soil water content ofthree shrubs forest is between5.14%and10.16%; the change of20-40cm is similar.But the soil of some shrubs types is thin, no20-40; the initial infiltration and steadyinfiltration rate is affected by soil texture and moisture. The initial infiltration rate andsteady infiltration rate of0~20cm were in between7.43-9.77mm/min and5.72-6.17mm/min; The soil moisture of three shrubs forest is positively related to vegetationdistribution and negative correlation to soil depth. The average water content of0-20cm was Vitex negundo L. var﹥Ziziphus jujuba var﹥Gleditsia hetero-phyiiaBunge, which is8.57%,8.18%,7.08%;6) The characteristics of rainfall and surface runoff characteristics show that: Inthe experimentation areas annual rainfall and annual effective rainfall of2008-2010are very imbalance. The averages of three annual rainfall were Vitex negundo L. varin380.87mm, Ziziphus jujuba var520.70mm, Gleditsia hetero-phyiia Bunge547.23mm. Rainfall mainly concentrated in the6-9month, especially in7-8. Heavyrainfall is concentrated also, which of the effective rainfall were accounted for about 60%; different shrubs forest surface runoff significantly: The annual average of threeyears runoff was in between2.93-11.90mm about Vitex negundo L. var four types;4.20-14.97mm about Ziziphus jujuba var three types;3.50-13.53mm about Gleditsiahetero-phyiia Bunge. It is necessary for the evaluation and value of soil and waterconservation through the classification of shrubs forest;7) The studies of the three shrubs forest biomass, Carbon fixation and nutrientcycling show that: The total biomass of three shrubs forest in different types isbetween1661.79-4622.61kg/hm2, significant difference among the types. Biomassallocation is root in between20-30%, branch and leaf were in between30-40%. Theannual biomass of the lesves accounted for more than65%, most products haveentered into the material circulation; shrubs forest provides soil organic C contentbetween283.7-735.87kg/hm2, which is31.75-43%of the total carbon fixation; Theannual retention of nutrient is small, the highest average36.98kg/hm2, the obviousdifferences among different types. Nutrient cycling rates of N and P2O5betweenthree shrubs forest was more than90%. The carbon and nutrients cycling is animportant content of shrubs forest ecological services, at the same time, the resultsp r o v i d e b a s i c d a t a f o r t h e c l a s s i f i c a t i o n m a n a g e m e n t o f s h r u b s;8) The index system of main shrubs forest ecosystem services assessment isestablished: using by frequency analysis method, and combining with the TaihangMountain ecological background, main problems and ecological conditions, consultthe relevant experts, the indexs are screening and adjustment, and finally we get theevaluation index system: water conservation, soil conservation, carbon fixation andoxygen production, accumulation of nutrients, biodiversity conservation;9) Accurate measurement of each index of ecological services of three shrubs forestshow that: the ecological services of shrubs all types are a significant difference, themeasurement of ecological services through the classification of shrubs forest isscientific and reasonable. About soil and water conservation quantities of three shrubsforest The reducing soil erosion quantity in different types is differences, a maximumof Vitex negundo VI303.53t/hm2, is the smallest jujube I7.13t/hm240times; aboutthe water conservation of shrubs forest is difference, the difference betweenmaximum and minimum is1392.7t/hm2, so the past evaluation of ecological serviceshas a great error the forest as no differences and not considering ecologicalheterogeneity vegetation community; The Carbon fixation and oxygen releasequantities were between352.16-1054.79kg/hm2, and1042.74-2880.36kg/hm2Thedifference between types of three shrubs communities is significant; the nutrientscontent of different shrubs in the leaves of are not the same, the difference of P of theshrubs is smaller; the accumulation of N element in Ziziphus jujuba var is maximal,ang of K elements in Gleditsia hetero-phyiia Bunge is maximum. This result has laid a theoretical foundation for cultivation of classification management and shruborientation of different shrubs forest; Three shrubs forest of different types ofShannon-Wiener index are between0.5659-2.5652, the biodiversity is simple;10) The calculation results of ecosystem services value show that: the percent ofdifferent ecosystem services indeies value was soil conservation and waterconservation about80%, fixing carbon and releasing oxygen and nutrientaccumulation of about6-8%, biodiversity about13-16%. The soil conservation andwater conservation have The maximum value, which is consistent with the actualecological construction in this region; although the values of fixing carbon andreleasing oxygen and nutrient accumulation are little, but because the barren soil, theecological fragile, so the ecological importance is significant; the calculation values ofecological services of different shrubs show that:4types of Vitex negundo was31803.05yuan/a.hm2,35793.58yuan/a.hm2,37739.81yuan/a.hm2,50954.46yuan/a.hm2; three types jujube were36960.35yuan/a.hm2,50489.86yuan/a.hm2,62809.13yuan/a.hm2; all types of Gleditsia hetero-phyiia Bunge were42071.48yuan/a.hm2,45404.28yuan/a.hm2,62847.53yuan/a.hm2. The values of Vitex negundoaveraged39072.72yuan/a.hm2, of Ziziphus jujuba var e is51753.11yuan/a.hm2,Gleditsia hetero-phyiia Bunge is50107.76yuan/a.hm2;11) Studies on shrub forest management measures and utilizations showed thatdifferent management measures had different effect on shrub forest biomass. Themaximum of biomass occurred in autumn. The biomass of Vitex negundo、Ziziphusjujuba var、Gleditsia hetero-phyiia Bunge were2.51kg/tree,1.89kg/tree, and2.84㎏/tree, respectively. The biomass of Vitex negundo、Ziziphus jujuba var、Gleditsiahetero-phyiia Bunge in autumn increased26.13%,15.24%, and51.87%, respectively,compared with those in spring. The best mow height was5cm, under which biomassof Vitex negundo、Ziziphus jujuba var、Gleditsia hetero-phyiia Bunge increased by16.08%,9.83%, and20.93%, respectively, compared with mow height of15cm. Thebiomass increased with the increase of fertilizing amount. Under the treatment of8g/m2, the biomass of Vitex negundo、Ziziphus jujuba var、Gleditsia hetero-phyiiaBunge increased by36.23%,6.98%, and19.25%, respectively, compared with CK.Under the treatment of grass cover, the biomass of Vitex negundo、Ziziphus jujubavar、Gleditsia hetero-phyiia Bunge increased by20.29%,9.3%and4.97%,respectively, compared with CK. The utilization research showed that Vitex negundo、Ziziphus jujuba var、Gleditsia hetero-phyiia Bunge were good fuel forest, with thecalorific value of0.56g,0.49g, and0.56g of standard coal. Bio-oil extractiontechnique indicated that liquid productivity reached60%under the conditionsdissociation temperature500℃, pneumatolysis airflow rate of4m3/h, and thefeedstock rate of3kg/h. Whatever, oxygen content of the production is40%. So further purification was essential to enlarge its application.