Biodiversity,profitability, and vegetation structure in a Mexican coffee agroecosystem

We studied the relationships of bird and small mammal species richness, composition, and abundance to vegetation structure and economic profitability across a coffee intensification gradient in central Veracruz, Mexico. We conducted 2 years of point count censuses for summer resident birds, 2 years of Sherman live trapping for small mammals, and gathered vegetation structure data at 147 sampling points distributed over 16 sites spanning a cultivation intensification gradient. We calculated net annual revenue per hectare as an index of profitability from economic and management data collected during interviews with plantation owners/managers. Both the species richness and abundance of forest-affiliated birds were significantly greater in floristically and structurally diverse ‘bajo monte’ coffee and forest compared with commercial polyculture coffee, which was, in turn, significantly richer than statistically indistinguishable specialized shade and sun coffee. Mammal capture rates were extremely low at all but two sites. Forest bird species richness and abundance were explained by multiple linear regression models that included statistically significant effects of shade cover, percent of trees with epiphytes, and canopy height. We found no clear relationship between profitability and biodiversity, with biodiverse bajo monte coffee plantations ranking among the most profitable under all price scenarios. The high profitability of biodiverse bajo monte coffee systems was not dependent on the inclusion of long-term environmental costs or premium pricing systems. Our results demonstrate that high-biodiversity coffee cultivation can be compatible with high profitability, and has significant potential for conserving biodiversity in coffee-growing regions, but only as a substitute for low-biodiversity coffee cultivation, not forest.     

Pollinator diversity increases fruit production in Mexican coffee plantations: The importance of rustic management systems

Pollination is an ecological process that provides important services to humans. Pollination service in agroecosystems depends on several factors, including the land management systems used by farmers. Here we focused on the effects of insect pollinator diversity on coffee fruit production along a gradient of management systems in central Veracruz, Mexico. The gradient ranged from low environmental impact management systems (the native forest is not completely removed) to high environmental impact management systems (the native forest is completely removed). We hypothesized that pollinator diversity should be higher in low-impact systems. Then, if fruit production is positively related to pollinator diversity, plantations with low-impact management systems should display higher fruit production than plantations with high-impact management systems. We used observational and experimental data to test this hypothesis. Our results indicated that low-impact management systems have higher species richness and relative diversity (measured with the Shannon-Wiener diversity index) of pollinators than high-impact management systems. In all cases, fruit production was positively related with species richness and diversity of pollinators. Moreover, fruit production was higher in low-impact than in high-impact management systems. These results suggest that the diversity of insect pollinators can be influenced by the management system applied by farmers, and that such effects may have strong consequences on coffee fruit production.     

Towards a climate change adaptation strategy for coffee communities and ecosystems in the Sierra Madre de Chiapas, Mexico

The mountain chain of the Sierra Madre de Chiapas in southern Mexico is globally significant for its biodiversity and is one of the most important coffee production areas of Mexico. It provides water for several municipalities and its biosphere reserves are important tourist attractions. Much of the forest cover outside the core protected areas is in fact coffee grown under traditional forest shade. Unless this (agro)forest cover can be sustained, the biodiversity of the Sierra Madre and the environmental services it provides are at risk. We analyzed the threats to livelihoods and environment from climate change through crop suitability modeling based on downscaled climate scenarios for the period 2040 to 2069 (referred to as 2050s) and developed adaptation options through an expert workshop. Significant areas of forest and occasionally coffee are destroyed every year by wildfires, and this problem is bound to increase in a hotter and drier future climate. Widespread landslides and inundations, including on coffee farms, have recently been caused by hurricanes whose intensity is predicted to increase. A hotter climate with more irregular rainfall will be less favorable to the production of quality coffee and lower profitability may compel farmers to abandon shade coffee and expand other land uses of less biodiversity value, probably at the expense of forest. A comprehensive strategy to sustain the biodiversity, ecosystem services and livelihoods of the Sierra Madre in the face of climate change should include the promotion of biodiversity friendly coffee growing and processing practices including complex shade which can offer some hurricane protection and product diversification; payments for forest conservation and restoration from existing government programs complemented by private initiatives; diversification of income sources to mitigate risks associated with unstable environmental conditions and coffee markets; integrated fire management; development of markets that reward sustainable land use practices and forest conservation; crop insurance programs that are accessible to smallholders; and the strengthening of local capacity for adaptive resource management.     

Agricultural land abandonment and natural forest re-growth in the Swiss mountains: A spatially explicit economic analysis

Natural forest re-growth reflects a decline in traditional agricultural practices that can be observed worldwide. Over the last few decades, natural forest re-growth has replaced much of the agricultural land in the Swiss mountains. This is a region where forms of traditional cultivation have preserved unique landscapes and habitats of high ecological value. This study aimed to characterise the locations in the Swiss mountains where agricultural land has been abandoned and overgrown by trees and bushes. Therefore, multivariate statistical models based on geo-physical and socio-economic variables were developed. Land-use change data were taken from two nationwide land-use surveys carried out in the 1980s and 1990s. In order to obtain reliable models, neighbourhood effects and the group structure in our data were accounted for. For the latter a robust estimation technique known as cluster-adjustment was used.Results show that forest re-growth is largely restricted to former alpine pastures, land with grass and scrub vegetation and agricultural land with groups of trees at mid to high altitudes, steep slopes, stony ground and a low temperature sum. Some relationships were not as expected, e.g. many of the new forest areas were found to be relatively close to roads. A new finding from this study was that forest re-growth is largely restricted to regions with immigration, higher proportions of part-time farms as opposed to full-time farms and high farm abandonment rates. By accounting for neighbourhood effects, the model fit was improved. The considerable residual deviance of the models was interpreted as the result of undetected local characteristics, such as poor water availability, small-scaled topographic peculiarities (e.g. small trenches, stonewalls, soil damages by cattle) and the individual's motivation to abandon or maintain cultivation. The conclusion made was that general policy measures for the whole mountain area are not suitable for the prevention of land abandonment and forest re-growth, and that policy measures must pay more attention to local characteristics and needs.     

Fire use: Is it really the cheaper land preparation method for large-scale plantations?

During the last two decades Indonesia has experienced immense forest and land fires. Often these fires are associated with extended drought and widespread use of fire to clear previously logged forest and other degraded land in preparation for oil palm, rubber, or pulpwood plantations. There are many reasons for the use of fire in land clearing activities, but probably the most important one is economics. There is still acceptance that fire is the cheapest, fastest, and most effective land clearing method with the added benefit of providing nutrients from ash residues. This paper provides a review of existing information on the financial costs and benefits of using fire for land clearing in agriculture and forestry plantations as compared with zero-burning techniques. The findings indicate that the economic advantage of fire use varies widely and depends on many factors, such as soil fertility, vegetation density, labour cost, equipment and training costs, and the costs of fire management. For large-scale land clearing, the financial analysis of the costs and benefits of fire versus zero-burning shows that when applied to low-volume vegetation, zero-burning methods are not more expensive than burning – and may actually be more cost effective in the long term. This is the case for clearing oil palm or rubber plantations for replanting, low secondary vegetation, and heavily logged-over forest. Under high-volume forest conditions, burning remains less expensive because it is more difficult, time consuming, and costly to dispose of high volumes of piled wood mechanically.     

Cause and consequence of landscape fragmentation and changing disturbance by socio economic development in mountain landscape system of South Korea

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最佳管理措施对非点源污染控制效果的预测——以北京密云县太师屯镇为例

选取北京市密云水库上游太师屯镇为研究区,针对该区农业非点源污染特征,设计了最佳管理措施(BMPs).同时,在非点源污染损失估算的基础上,率先尝试从经济学角度预测8种不同非点源污染措施在控制氮、磷和泥沙流失的效果及所获得的环境效益、经济效益,并将各单项措施的控制效率进行了比较分析.研究结果表明：改变土地利用类型的3种措施中,25°以上荒草坡还林措施效果最好,对总氮、总磷、泥沙流失的控制效果都超过15%,最高可达30%以上,且经济效益最大;25°以上坡耕地还林效果次之,对总氮、总磷、泥沙流失的控制效果都超过5%,最高可达12%;15°~25°坡耕地变果园措施最差,对总氮、总磷、泥沙流失的控制效果一般为4%~8%.坡度为0°~15°坡耕地在土壤侵蚀控制中具有重要地位;坡耕地植物篱和保护性耕作对土壤侵蚀类非点源污染的控制效果相近,削减的污染损失占非点源污染损失总价值的13%,具有明显的环境效益.针对畜禽养殖污染设计的农村户用沼气池,其经济效率在10%左右;测土施肥技术可减少氮素流失、节约大量化肥,且削减的污染损失达到非点源污染损失总价值的19%.作为综合污染控制措施的河岸缓冲带,可以有效地拦截氮、磷和泥沙的流失,对泥沙的控制效果最好,为83%,对氮的控制效果最低,仅为27%;而从经济效益方面比较,缓冲带减少氮素流失所获得的经济效益最大,约为该措施总经济效益的56%,泥沙次之,占28%;植被缓冲带削减非点源污染的总经济效率最高,可达35%,折合经济价值约1.69×106元.     

采伐与人工更新对红壤丘陵区森林面积和地上生物量的影响模拟——以会同县磨哨林场为例

我国人工林生态系统正面临着结构退化、功能降低等问题,迫切需要通过合理的森林管理方案实施有效的管理措施加以改善。本文以湖南省会同县磨哨林场为研究区,应用生态系统过程模型PnET-II和森林景观模型LANDIS-II,采用情景模拟的方式研究未来100年低、中、高强度的采伐措施以及人工更新对森林面积和地上生物量的影响。结果表明：（1）随着采伐强度增加,人工针叶林面积持续减少、森林AGB下降幅度加大;（2）人工更新措施能够使人工针叶林面积保持稳定,促进其AGB积累,有利于人工林更新与生长;（3）对人工林采取中等强度采伐且实施伐后人工更新的管理方案有利于我国南方以杉木（Cunninghamia lanceolata）、马尾松（Pinus massoniana）为主要树种的人工林地区实现森林可持续经营。     

Hydrological eco-service of rubber plantations in Hainan Island and its effect on local economic development

The impacts of economic forest on global environmental change(GEC) are one of the hot issues in environmental study. Based on the 3-year observation data and 40-year climate data, GEC and analysis of the hydrological dynamic characteristics of rubber plantations and estimate of the water balance in the rubber plantations in Hainan Island were made. The results showed that the rainfall intercepted by thecanopy of the plantations accounted for 11.4-5 % of the annual rainfall, the total runoff for 23.71%, the total evaporation and transpiration for 63.24%, the soil moisture storage for 1.6%. Analysis of the 40year rainfall data in the 19 counties of Hainan Island during 1951—1990 showed that the large-scale substitution of the natural vegetation with the rubber plantations had no significant effect on the local rainfall in Hainan Island. The main reasons are (1) 80% of the rainfall in Hainan is brought by typhoons; (2) the proportion of 11.6% rubberplantations in total forest coverage in Hainan is not enough to influence the local rainfall in Hainan Island; and (3) although the rubberplantation is artificial vegetation, it has the similar function to the tropical rain forest. Analysis of the total water resource and I‘otal GDP ofHainan in 1997 showed that the economic benefit resulted from the water resource was 1.0 RMB Yuan/m3 . The value of hydrological of therubber plantation in Hainan was 113.9 million RMB Yuan/a when compared with the tropical rain forest. The paper reaches conclusion that the hydrological eco-service function of rubber plantation has been enhanced after transformed from natural vegetation, which includes the natural service and powerful social service.     

Climate change adaptation,mitigation and livelihood benefits in coffee production: where are the synergies?

There are worldwide approximately 4.3 million coffee (Coffea arabica) producing smallholders generating a large share of tropical developing countries’ gross domestic product, notably in Central America. Their livelihoods and coffee production are facing major challenges due to projected climate change, requiring adaptation decisions that may range from changes in management practices to changes in crops or migration. Since management practices such as shade use and reforestation influence both climate vulnerability and carbon stocks in coffee, there may be synergies between climate change adaptation and mitigation that could make it advantageous to jointly pursue both objectives. In some cases, carbon accounting for mitigation actions might even be used to incentivize and subsidize adaptation actions. To assess potential synergies between climate change mitigation and adaptation in smallholder coffee production systems, we quantified (i) the potential of changes in coffee production and processing practices as well as other livelihood activities to reduce net greenhouse gas emissions, (ii) coffee farmers’ climate change vulnerability and need for adaptation, including the possibility of carbon markets subsidizing adaptation. We worked with smallholder organic coffee farmers in Northern Nicaragua, using workshops, interviews, farm visits and the Cool Farm Tool software to calculate greenhouse gas balances of coffee farms. From the 12 activities found to be relevant for adaptation, two showed strong and five showed modest synergies with mitigation. Afforestation of degraded areas with coffee agroforestry systems and boundary tree plantings resulted in the highest synergies between adaptation and mitigation. Financing possibilities for joint adaptation-mitigation activities could arise through carbon offsetting, carbon insetting, and carbon footprint reductions. Non-monetary benefits such as technical assistance and capacity building could be effective in promoting such synergies at low transaction costs.     

Relationships between diversity of grassland vegetation, field characteristics and land use management practices assessed at the farm level

In order to assess the impact of policies to encourage extensification in less favoured areas and improve our knowledge of extensive livestock systems, we analyzed relationships between the diversity of grassland vegetation and land use management practices and field characteristics. This study, conducted on a mountainous area in the centre of France, was based on 149 fields, mainly of natural grasslands belonging to 7 farmers. Regression analyses were performed to analyze the relations between the grassland vegetation types (five types established from the list of dominant species), management practices (cutting versus grazing and fertilization) and the topographic (altitude and aspect) and topologic (slope, distance and surface area) characteristics of the fields. The land use management rules used by the farmers were studied by specifying the grazing management rules of the herd (dairy cows), as well as those for conserved forage (mainly hay or silage) and were identified from observations mentioned on the “grazing schedules”, as well as from interviews at the beginning, in the middle and at the end of the study period. The statistical analysis showed that neither the topographic characteristics of the fields nor the distance from the cowshed or surface area were correlated with the grassland vegetation types. It was the management practices used, largely determined by the field slope, which determined the grassland vegetation type. On the other hand, farmers’ statements showed that the grazing and cutting management rules were mostly determined by the slope of the fields and the distance from the cowshed and, to a lesser extent, by the altitude and aspect. These results showed that the farmers take into consideration environmental differences when choosing fields to allocate for grazing and cutting at different seasons, particularly when they are constrained by these features. Nevertheless, when the constraints were minimal, a wide diversity of grassland vegetation types was also observed. This diversity was a result of attributing different functions to the fields which led to different management practices (defoliation methods and fertilization) and, thus, to different grassland vegetation types. Consequently, for farms where animal feed requirements vary according to the time of the year and the type of animal, we suggest that diversity in the grassland vegetation types is a sound component of these livestock systems.     

会同森林生态实验站磨哨林场森林碳密度及分配特征

我国具有全世界最大面积的人工林,在全球气候变暖的大背景下,人工林的固碳能力越来越引起关注。研究选择具有长期观测数据的会同森林生态实验站磨哨林场作为研究区,对比分析了9种不同森林类型生态系统各组分（乔木层、林下植被层、凋落物层、土壤层）碳密度及分配特征（人工林8种,林龄范围为25~32 a：杉木林、马尾松林、湿地松林、杉木+樟树林、杉木+火力楠林、马尾松+木荷林、木荷林、火力楠林;天然林1种,平均林龄为63 a：红栲+青冈+刨花润楠林）。结果表明：1）磨哨林场生态系统碳密度平均为261.61 t/hm²,固碳能力较高,其中,马尾松+木荷林以及杉木+火力楠林两种人工混交林的生态系统碳密度最高,天然林位于第5位;2）乔木层和土壤层是磨哨林场森林生态系统碳密度的主体,占98.23%,林下植被层和凋落物层对整个生态系统碳密度贡献较小;3）乔木层中树干部分的碳密度占绝对优势,其次为根和枝,皮最小;土壤层碳密度及分配比例随深度增加而降低,0~20 cm碳密度占整个土壤层比例最高。     

Long-term impacts of land-use change on dynamics of tropical soil carbon and nitrogen pools

Land-use changes, especially the conversion of native forest vegetation to cropland and plantations in tropical region, can alter soil C and N pools and N availability for plant uptake. Deforestation, followed by shifting cultivation and establishment of rubber tree plantation, is a common land-use change in Xishuangbanna, southwest China. However the influence of this kind of land-use change on soil C and N dynamics in this region remains poorly understood, This study was conducted to assess the effects of land-use change on soil C and N pools. Soil samples were collected on five adjacent plots, which belong to three land-use types including secondary forest-an acuminate banana( Musa itinerans) secondary forest and a male bamboo( Dendrocalamus membranaceae) secondary forest, shifting cultivation, and rubber tree ( Hevea brasiliensis (H. B. K. ) Muell. Arg. ) plantation(one plot is 3-year-old, and another is 7-year-old). We measured soil bulk density (BD), pH value, moisture content and concentrations of soil organic carbon(SOC), total soil nitrogen(TSN), and inorganic N(NO3^- -N and NH4^ -N) at 0--3, 3--20, 20--40 and 40--60cm depths, and calculated C and N pools in 0--20, 20--40, 40--60, and 0--60 cm soil layers. Compared with the adjacent secondary forests, shifting cultivation and establishment of rubber tree plantations resulted in significant decline in concentrations and stocks of SOC and TSN in 0--20 and 0--60cm soil layers, and increase in pH and bulk density at 0--3, 3--20, and 20--40cm depths. Soil moisture content decreased only in 0--20cm surface soils in shifting cultivation and plantations. The dynamics of mineral N was much more complex, which had different trends among depths and ecosystems. Compared with the secondary forests, SOC stocks in 0--20cm surface soils in shifting cultivation and rubber tree plantations(3-year-old plantation and 7-year-old plantation) decreased by 34.0%, 33%, and 23% ; and TSN stocks decreased by 32.2%, 20.4%, and 20.4%, respectively,whereas the decreases of SOC and TSN stocks in 0--60cm soil layers were much less. The results indicated that C and N losses were mainly occurred in 0--20cm surface soil, followed by 20--40cm layer.     

Mitigation and adaptation synergy in forest sector

Mitigation and adaptation are the two main strategies to address climate change. Mitigation and adaptation have been considered separately in the global negotiations as well as literature. There is a realization on the need to explore and promote synergy between mitigation and adaptation while addressing climate change. In this paper, an attempt is made to explore the synergy between mitigation and adaptation by considering forest sector, which on the one hand is projected to be adversely impacted under the projected climate change scenarios and on the other provide opportunities to mitigate climate change. Thus, the potential and need for incorporating adaptation strategies and practices in mitigation projects is presented with a few examples. Firstly, there is a need to ensure that mitigation programs or projects do not increase the vulnerability of forest ecosystems and plantations. Secondly, several adaptation practices could be incorporated into mitigation projects to reduce vulnerability. Further, many of the mitigation projects indeed reduce vulnerability and promote adaptation, for example; forest and biodiversity conservation, protected area management and sustainable forestry. Also, many adaptation options such as urban forestry, soil and water conservation and drought resistant varieties also contribute to mitigation of climate change. Thus, there is need for research and field demonstration of synergy between mitigation and adaptation, so that the cost of addressing climate change impacts can be reduced and co-benefits increased.     

Matching national forest policies and management practices for climate change adaptation in Burkina Faso and Ghana

Many studies have suggested various kinds of forest policies, management planning and practices to help forests adapt to climate change. These recommendations are often generic, based mostly on case studies from temperate countries and rarely from Africa. We argue that policy and management recommendations aimed at integrating adaptation into national forest policies and practices in Africa should start with an inventory and careful examination of existing policies and practices in order to understand the nature and extent of intervention required to influence the adaptation of forest ecosystems to climate change. This paper aims to contribute to closing this gap in knowledge detrimental to decision making through the review and analysis of current forest policies and practices in Burkina Faso and Ghana and highlighting elements that have the potential to influence the adaptation of forest ecosystems to climate change. The analysis revealed that adaptation (and mitigation) are not part of current forest policies in Burkina Faso and Ghana, but instead policies contain elements of risk management practices which are also relevant to the adaptation of forest ecosystems. Some of these elements are found in policies on the management of forest fires, forest genetic resources, non-timber resources, tree regeneration and silvicultural practices. To facilitate and enhance the management of these elements, a number of recommendations are suggested. Their implementation will require experienced and well-trained forestry personnel, financial resources, socio-cultural and political dimensions, and the political will of decision makers to act appropriately by formulating necessary policies and mainstreaming adaptation into forest policy and management planning.     

Environmental and socio-economic impacts of institutional reforms on the agricultural sector of Vietnam: Land suitability assessment for Robusta coffee in the Dak Gan region

After the reunion of North and South Vietnam in 1975, the area under small-holder, irrigated cultivation of Robusta coffee increased by a factor of 10 in the Central Highlands. The actual coffee acreage in Dak Lak province is estimated to be over 260,000 ha, representing 60% of the national production, with 405,000 t year⁻¹ for the world market. Vietnam is presently the second largest exporter worldwide and expansion is still going on. In cooperation with the National Institute for Agricultural Planning and Projection (NIAPP), a 5-year development project “Land Evaluation for Land Use Planning and Development of Sustainable Agriculture in the Central Highlands of South Vietnam” was set up, with a goal of diagnosing the sustainability of the rapidly expanding Robusta coffee sector in Central Vietnam. This paper describes the reasons for this quick expansion and investigates the consequences in ecological and social terms. This is done based on a large-scale natural resources inventory, land suitability analysis for Robusta coffee and participatory rural appraisal combined with secondary statistical records from Dak Gan commune. It is representative of the Central Highlands in terms of geomorphological and pedological variability, ethnic identity and with regard to trade-offs between forest conservation and coffee expansion at the cost of available water stocks. Local institutional reforms in the eighties have accelerated coffee expansion in three ways: demographic resettlement, socio-economic liberalization and legislation towards land ownership. Interaction between these three factors has induced a second spontaneous migration flow towards the Highlands in the nineties. Forest area declined by 19% and was converted to coffee plantations, encouraged by the high economic return of this cash crop. The results indicate that this has happened in an haphazard manner and led to a mismatch between the present land use pattern and the natural resource base. Unsustainable land use manifests itself at four levels. (i) The areal limits for sustainable coffee production have been exceeded. (ii) As a consequence over 74% of the present coffee stand is situated on sub-optimal land units. (iii) An excessive coffee area in combination with over-irrigation is likely to deplete groundwater resources. (iv) And paradoxically 24.3% of suitable soils for coffee production is still under forest in Dak Gan. In turn this leads to large-scale environmental and socio-economic decline: soil erosion, water scarcity and social inequity resulting in conflicts between migrants and the indigenous tribes. Besides local reforms, world trade liberalization changed the global coffee market in the late nineties from a regulated system to a free trade market. This fostered global oversupply, which in combination with a stagnant coffee demand suppressed the world market price. Since Vietnam became the second world producer of Robusta, prices have declined by a factor of 3, not only affecting the local sector but households worldwide.     

格式栲天然林水源涵养功能的研究

本文通过对三明莘口格式栲天然林与人工林的林冠层,林木植被层和林褥层及林下土壤层的持水量,土壤渗透性能差异等的研究。结果表明:格式栲天然林林分持水总量比格式持和楠木人工林分别增加 225.131t/ha 和 296.558t/ha;土壤稳渗值高达 8.09 mm/min,分别是格式栲和楠木人工林的3.3倍和25.3倍。格式栲天然林具有良好的水源涵养功能。     

珠江三角洲森林生态系统碳密度分配及其储量动态特征

 在测定植被的含碳率与土壤有机碳含量的基础上,研究了南亚热带珠江三角洲地区森林生态系统碳密度分配及其储量动态.结果表明:植被平均含碳率为35.81%~51.60%,按照生物量加权的含碳率为46.57%~52.45%;土壤有机碳含量及其差异程度为表层最高,随土壤深度增加,有机碳含量及其差异逐渐减小;相同龄级的植被含碳率与土壤含碳量均表现为阔叶林>针阔混交林>针叶林,不同龄级的森林均表现为成龄林>中龄林>幼龄林.植被碳密度与土壤碳密度范围分别为23.58~139.18,55.54~151.16t/hm2,而且土壤分配比例均大于植被分配比例,但土壤分配比例随着龄级的增长呈下降趋势.1989~2003年间,珠江三角洲森林生态系统总体碳储量及其碳密度均呈上升趋势,这说明在改革开放高速发展时期珠江三角洲森林生态系统由于生物量的增加,起到了重要的碳汇功能,而且其碳汇功能正逐步提高.     

江苏省徐淮地区的景观生态问题与对策

在对江苏省徐淮地区景观生态分类与制图研究的基础上，分析了该地区稀疏植被景观，常绿针叶林景观，落叶阔叶林景观，旱地作物景观，水旱轮作景观，湖泊景观等主要景观型的生态２问题，并提出了相应的生态对策。