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1.
Human activities are affecting the environment at continental and global scales. An example of this is the Mississippi basin where there has been a large scale loss of wetlands and water quality deterioration over the past century. Wetland and riparian ecosystems have been isolated from rivers and streams. Wetland loss is due both to drainage and reclamation, mainly for agriculture, and to isolation from the river by levees, as in the Mississippi delta. There has been a decline in water quality due to increasing use of fertilizers, enhanced drainage and the loss of wetlands for cleaning water. Water quality has deteriorated throughout the basin and high nitrogen in the Mississippi river is causing a large area of hypoxia in the Gulf of Mexico adjacent to the Mississippi delta. Since the causes of these problems are distributed over the basin, the solution also needs to be distributed over the basin. Ecotechnology and ecological engineering offer the only ecologically sound and cost-effective method of solving these problems. Wetlands to promote nitrogen removal, mainly through denitrification but also through burial and plant uptake, offer a sound ecotechnological solution. At the level of the Mississippi basin, changes in farming practices and use of wetlands for nitrogen assimilation can reduce nitrogen levels in the River. There are additional benefits of restoration of wetland and riverine ecosystems, flood control, reduction in public health threats, and enhanced wildlife and fisheries. At the local drainage basin level, the use of river diversions in the Mississippi delta can address both problems of coastal land loss and water quality deterioration. Nitrate levels in diverted river water are rapidly reduced as water flows through coastal watersheds. At the local level, wetlands are being used to treat municipal wastewater. This is a cost-effective method, which results in improved water quality, enhanced wetland productivity and increased accretion. The problems in the Mississippi basin serves as an example for other watersheds in the Gulf of Mexico. This is especially important in Mexico, where there is a strong need for economical solutions to ecological problems. The Usumacinta delta-Laguna de Terminos regional ecosystem is an example where ecotechnological approaches offer realistic solutions to environmental problems.  相似文献   

2.
The ecological role of historical land use has rarely been explored in the context of grassland restoration. We conducted a 4‐year field experiment in a steppe and an old field in Inner Mongolia in northern China to examine the influence of historical land use and water availability on ecosystem restoration. Species richness, evenness, and plant cover were higher in the steppe than in the old field. The steppe was more temporally stable compared with the old field in terms of species richness, evenness, plant density, and cover. Water addition increased peak aboveground biomass, belowground net primary productivity, species richness, plant density, and cover in both the steppe and the old field. Water addition also enhanced the stability of ecosystems and the restoration of grassland. Our findings suggested that historical land use determines community structure and influences the process of grassland restoration. Converting grasslands to farmland in semiarid areas can cause the long‐term loss of biodiversity and instability of ecosystem with consequent impacts on ecosystem services. The amendment of limited resources is an effective practice to increase the success of ecosystem restoration.  相似文献   

3.
Diversion of freshwater can cause significant changes in hydrologic dynamics and this can have negative consequences for fish populations. Additionally, fishes can be directly entrained into diversion infrastructure (e.g. canals, reservoirs, pumps) where they may become lost to the population. However, the effect of diversion losses on fish population dynamics remains unclear. We used 15 years of release and recovery data from coded-wire-tagged juvenile Chinook Salmon (Oncorhynchus tshawytscha) to model the physical, hydrological and biological predictors of salvage at two large water diversions in the San Francisco Estuary. Additionally, entrainment rates were combined with estimates of mortality during migration to quantify the proportion of total mortality that could be attributed to diversions. Statistical modeling revealed a strong positive relationship between diversion rate and fish entrainment at both diversions and all release locations. Other significant relationships were specific to the rivers where the fish were released, and the specific diversion facility. Although significant relationships were identified in statistical models, entrainment loss and the mean contribution of entrainment to total migration mortality were low. The greatest entrainment mortality occurred for fish released along routes that passed closest to the diversions and certain runs of Chinook Salmon released in the Sacramento River suffered greater mortality but only at the highest diversion rates observed during the study. These results suggest losses at diversions should be put into a population context in order to best inform effective management of Chinook Salmon populations.  相似文献   

4.
Nitrate-nitrogen retention in wetlands in the Mississippi River Basin   总被引:1,自引:0,他引:1  
《Ecological Engineering》2005,24(4):267-278
Nitrate-nitrogen retention as a result of river water diversions is compared in experimental wetland basins in Ohio for 18 wetland-years (9 years × 2 wetland basins) and a large wetland complex in Louisiana (1 wetland basin × 4 years). The Ohio wetlands had an average nitrate-nitrogen retention of 39 g-N m−2 year−1, while the Louisiana wetland had a slightly higher retention of 46 g-N m−2 year−1 for a similar loading rate area. When annual nitrate retention data from these sites are combined with 26 additional wetland-years of data from other wetland sites in the Basin Mississippi River (Ohio, Illinois, and Louisiana), a robust regression model of nitrate retention versus nitrate loading is developed. The model provides an estimate of 22,000 km2 of wetland creation and restoration needed in the Mississippi River Basin to remove 40% of the nitrogen estimated to discharge into the Gulf of Mexico from the river basin. This estimated wetland restoration is 65 times the published net gain of wetlands in the entire USA over the past 10 years as enforced by the Clean Water Act and is four times the cumulative total of the USDA Wetland Reserve Program wetland protection and restoration activity for the entire USA.  相似文献   

5.
Ecosystem health is an important research topic. Several studies have mainly focused on ecosystem health assessment (EHA) on a large or medium scale, with only a few studies using small grids as research units. Based on the Vigor–Organization–Resilience–Services (VORS) model, which can adequately compute multiple ecosystem values for each land use type, this study used a scale with a 250 m × 250 m grid as the spatial research unit to quantitatively and dynamically assess the ecosystem health and analyze its spatial implications in the Liuxi River Basin, Guangzhou, China. The results showed that the ecosystem health level of each land use type is ranked as follows: water areas > shrublands > grasslands > wetlands > broadleaf forests > drylands > construction land. The amount of construction land area rapidly increased from 2005 to 2018 at the cost of a substantial loss of broadleaf forests, shrublands, and wetlands, which led to a decline in ecosystem health values. Thus, anthropogenic activities such as urbanization and deforestation were the main driving factors affecting land use changes and spatial distribution of ecosystem health. Furthermore, the correlation between ecosystem services (ES) and ecosystem health was the strongest, indicating that ES was a key indicator contributing to ecosystem health in the Liuxi River Basin. The ecosystem health of the Liuxi River Basin had a significant positive spatial aggregation effect which gradually increased from 2005 to 2018. The high–high aggregation areas were mainly clustered in water areas and grasslands, and the low–low aggregation areas were mainly clustered in construction zones and paddy fields. This study provides an important reference for evaluating ecosystem health based on the VORS model, ecological conservation, and the management of small basins in the context of rapid urbanization.  相似文献   

6.
基于InVEST模型的海南岛三大流域生境质量时空演变   总被引:1,自引:0,他引:1  
基于1980—2020年5期土地利用数据,采用InVEST模型,综合应用土地利用转移、生境质量变化率和空间统计分析等方法,探究海南岛三大流域(南渡江、昌化江、万泉河)生境质量变化及其空间分布特征。结果表明: 海南岛三大流域土地利用类型以林地为主,占总面积的70%以上。1980—2020年间,海南岛三大流域建设用地面积增加量最大,达169.09 km2,主要来自耕地和林地。研究区生境质量整体呈现出上游源头区高、中下游区域低的空间分布格局,研究期间生境质量指数总体表现为先略微升高后显著降低的变化特征。在三大流域中,万泉河流域生境质量最高,昌化江流域次之,南渡江流域最低,且南渡江流域生境质量波动较大,受人为干扰较强。1980—2020年间,三大流域生境质量变化率总体降低0.5%,且在2010—2020年间退化明显。1980—2020年间,研究区生境质量在空间分布上具有较强的自相关性和显著的聚集性。三大流域生境质量的热点区主要集中在流域上游源头区域;冷点区主要分布在三大流域的入海口区域以及南渡江的中下游地区。研究结果可为海南岛三大流域生物多样性保护和生态修复提供数据支撑及科学参考。  相似文献   

7.
Upper Mississippi River Restoration (UMRR) was implemented to monitor environmental status and trends and restore degraded habitat. There was little experience conducting restoration in large rivers, and engineering and ecological integration evolved through project implementation. Loss of depth in backwaters and side channels, excessive biological oxygen demand, increased currents, and low water temperatures were common symptoms of backwater eutrophication that were primary objectives for implementing UMRR. Biological outcome monitoring was initially funded for six projects using the most common methods to restore aquatic and wetland habitat. UMRR island construction occurred as four generations of learning. Current plans represent a comprehensive restoration approach including: physical process modeling (i.e. hydraulic and wind‐wave modeling) of existing conditions and alternative restoration measures. Habitat Rehabilitation and Enhancement Projects, fish response monitoring validated winter habitat suitability models. Long term fish population monitoring indicates sustainable recovery, and now population interaction among restored lakes is under investigation. Isolated wetland management in Illinois River backwater lakes can achieve bottom consolidation that promotes emergent wetland habitat response that migratory waterfowl exploit in large numbers. Adult fish movement between the river and management units is restricted to flood stage or through control structures and post‐project movements into the lake for overwintering were not apparent. The lack of Illinois River overwintering habitat is shown by an abundance of young fish and few older fish in status and trends monitoring. Upper Mississippi River System ecosystem restoration practitioners have implemented ecosystem restoration science and practice in a manner that exemplifies the best intent of adaptive management.  相似文献   

8.
Ren  Ling  Rabalais  Nancy N.  Turner  R. Eugene 《Hydrobiologia》2020,847(8):1831-1850

Diversion of river waters to adjacent estuaries may occur during wetland restoration, navigation channel development, or storms. We proposed that diversions of nitrogen- and phosphorus-enriched waters from the river to estuarine waters would result in increased phytoplankton biomass and shifts to noxious or harmful algal blooms. We tested this hypothesis by conducting four seasonal microcosm experiments in which Mississippi River water was mixed at different volume ratios with ambient estuarine waters of three lakes in the upper Barataria Basin, Louisiana, USA. These lakes included two brackish lakes that were in the path of diverted Mississippi River water, and a freshwater lake that was not. The results from the 3- to 8-day experiments yielded a predictable increase in phytoplankton biomass related to nutrient additions from Mississippi River water. The subsequent decreases in the dissolved nitrate + nitrite, soluble reactive phosphorus, and silicate concentrations explained 76 to 86% of the increase in chlorophyll a concentrations in the microcosms. Our experiments showed that cyanobacteria can successfully compete with diatoms for N and P resources even under non-limiting Si conditions and that toxic cyanobacteria densities can increase to bloom levels with increased Mississippi River water inputs to ambient waters in the microcosms. Diversions of Mississippi River into adjacent estuarine waters should be considered in relation to expected and, possibly, unexpected changes in phytoplankton communities to the receiving waters and coastal ecosystems.

  相似文献   

9.
Tropical forest restoration is increasingly seen as an activity that may counteract or reduce biodiversity loss. However, few studies monitor fauna or consider measures of functional diversity to assess restoration success. We assessed the effect of a tropical montane forest restoration program on species and functional diversity, using amphibians as the target group. We compared amphibian assemblages in three types of land use: restoration areas, tropical montane cloud forest (TMCF; reference ecosystem) and cattle pastures (degraded ecosystem) in southern Mexico. We also described microclimate, microhabitat heterogeneity, woody vegetation structure and diversity for each type of land use, and their relationship to amphibian species and functional diversity. Compared to TMCF, restoration areas had similar environmental conditions. However, amphibian species richness was similar in the three types of land use and abundance was lower in the restoration areas. In TMCF, the amphibian assemblage was dominated by forest-specialist species, the pastures by generalist species, and the restoration areas by a combination of both species types. Interestingly, functional richness, functional evenness and functional divergence did not vary with land use, though the number of functional groups in restoration areas and TMCF was slightly higher. Overall, the results suggest that after seven years, active restoration provided habitat heterogeneity and recovered woody vegetation capable of maintaining amphibian species and functional groups similar to those inhabiting TMCF. Forest fragments adjacent to restoration areas seem to facilitate fauna recolonization and this emphasizes the importance of the conservation of the reference ecosystems to achieving restoration success.  相似文献   

10.
A Markov-chain transition model (FORSUM) and Monte Carlo simulations were used to simulate the succession patterns and predict a long-term impact of flood on the forest structure and growth in the floodplain of the Upper Mississippi River and Illinois River. Model variables, probabilities, functions, and parameters were derived from the analysis of two comprehensive field surveys conducted in this floodplain. This modeling approach describes the establishment, growth, competition, and death of individual trees for modeled species on a 10,000-ha landscape with spatial resolution of 1 ha. The succession characteristics of each Monte Carlo simulation are summed up to describe forest development and dynamics on a landscape level. FORSUM simulated the impacts of flood intensity and frequency on species composition and dynamics in the Upper Mississippi River floodplain ecosystem. The model provides a useful tool for testing hypotheses about forest succession and enables ecologists and managers to evaluate the impacts of flood disturbances and ecosystem restoration on forest succession. The simulation results suggest that the Markov-chain Monte Carlo method is an efficient tool to help organize the existing data and knowledge of forest succession into a system of quantitative predictions for the Upper Mississippi River floodplain ecosystem.  相似文献   

11.
A diversion of Mississippi River water into Lake Pontchartrain, Louisiana, USA by way of the Bonnet Carre Spillway has been proposed as a restoration technique to help offset regional wetland loss. An experimental diversion of Mississippi River water into Lake Pontchartrain was carried out in April 1994 to monitor the fate of nutrients and sediments in the spillway and Lake Pontchartrain. Approximately 6.4×108 m3 of Mississippi River water was diverted into Lake Pontchartrain over 42 days. As water passed through the Bonnet Carre Spillway, there were reductions in total suspended sediment concentrations of 82–83%, nitrite+nitrate (NOx) of 28–42%, in total nitrogen (TN) of 26–30%, and in total phosphorus (TP) of 50–59%. 3.9±1.1 cm of accretion was measured in the spillway. Nutrient concentrations at the freshwater plume edge in Lake Pontchartrain compared to the Mississippi River were lower for NOx (44–81%), TN (37–57%), and TP (40–70%), and generally higher for organic nitrogen (−7–57%). The Si:N ratio generally increased and the N:P ratio decreased from the river to the plume edge. Nutrient stoichiometric ratios indicate water at the plume edge was not silicate limited, suggesting conditions favoring diatomic phytoplankton.  相似文献   

12.
Estuarine nutrient enrichment is thought to be controlled by land use patterns in coastal watersheds. Hence, the objective of this work was to conduct a watershed analysis in two adjacent river basins with different land use characteristics to determine their influence on estuarine ecosystem response in the Guadalupe Estuary, Texas, U.S.A. All data sources for this study were available electronically on the Internet; the data were mined, managed, analyzed and transformed to simulate the estuarine ecosystem response to watershed-derived nutrient loads. Between 1992 and 2001, developed land use/land cover increased the most while forest cover decreased the most in both basins. Two hydrologic units nearest the coast were responsible for the greatest change in land cover. Nutrient concentrations and loads were significantly higher in the San Antonio River Basin than in the Guadalupe River Basin. Both river basins exhibited the highest flows ever recorded in 1992, however the magnitude of difference in loads between the two coastal hydrologic units for a wet and dry year was much greater in the Guadalupe River Basin (GRB) than in the San Antonio River Basin (SARB); this difference supports the concept that the GRB is a nonpoint source dominated system and SARB is a point source dominated system. There was a strong correlation between developed land use and nutrient concentrations in river water; the GRB had less developed land use and lower nutrient concentrations while the SARB had more developed land use and higher nutrient concentrations. Estuarine ecosystem response differed in the timing, duration and magnitude of DIN, phytoplankton and zooplankton when nitrogen loads from the Lower Guadalupe River were used as opposed to the Lower San Antonio. The two basins studied differ in their fundamental characteristics, i.e. precipitation, flow, human population density, etc., resulting in different drivers of nitrogen loading, point sources in the San Antonio River Basin and nonpoint sources in the Guadalupe River Basin, therefore, differing estuarine ecosystem responses.  相似文献   

13.
Constructed Crevasses and Land Gain in the Mississippi River Delta   总被引:1,自引:0,他引:1  
Extensive land loss, which is mostly wetland loss, has taken place during this century in the Mississippi River delta and other river deltas. Our purpose was to evaluate the effectiveness of constructing “artificial” crevasses, or cuts in the natural levee, made by the U.S. Fish and Wildlife Service in the Delta National Wildlife Refuge (DNWR) to slow or reverse this type of land loss. Land growth of the crevasses was determined from aerial photographs and was related to crevasse-site characteristics. The newly constructed crevasses create emergent wetlands after 2 years of subaqueous growth at about 4.7 ha/year and an average cost of $21,377 per crevasse. The present total cost per hectare declines with age as new land builds, and it will equal $48 per hectare if all the open water in the receiving ponds fills in. At these rates, the net land loss rates in the DNWR measured from 1958 to 1978 would be compensated for by the building of 63 crevasses, 24 of which are already in place.  相似文献   

14.
Environmental decision‐making issues in the Atchafalaya River Basin (ARB), Louisiana require innovative approaches that combine scientific understanding and local stakeholder values. Management of the ARB has evolved from strong federal control to establish the ARB as a primary floodway of the Mississippi River and Tributaries Project to a state and federal collaboration to accommodate fish and wildlife resource promotion, recreational opportunities, and economic development. The management policy has expanded to include a growing number of stakeholders, but the decision‐making process has not kept pace. Current conflicts among many local stakeholder groups, due in part to their lack of involvement in the decision‐making process, impede restoration efforts. The absence of a long‐term collective vision for the ARB by both local stakeholder groups and management agencies further confounds these efforts. This paper proposes a process to apply a structured decision‐making framework, a values‐based approach that explicitly defines objectives, to promote stakeholder‐driven restoration efforts in the ARB and to better prepare for and manage long‐term environmental issues. The goals of this approach are: (1) to create a process founded on stakeholder values and supported by rigorous scientific assessment to meet management agency mandates and (2) to establish a transparent process for restoration planning in the ARB that incorporates current and future non‐governmental stakeholders into the decision‐making process. Similar frameworks have been successful in other river basins; we feel the structure of current restoration efforts in the ARB is well‐suited to adopt a values‐focused management framework.  相似文献   

15.
北京市白河和潮河流域生态健康评价   总被引:5,自引:0,他引:5  
徐菲  王永刚  张楠  王旭  范清 《生态学报》2017,37(3):932-942
选取北京市重要的饮用水源密云水库上游白河和潮河流域,结合北京山区流域生态现状,构建了涵盖水域生境结构、水生生物、生态压力和陆域生态格局与功能、生态压力5大类13项指标的评价指标体系,开展了流域生态健康评价。结果表明白河和潮河流域的健康状态整体处于良好等级,但水生生物和陆域生态格局状况相对较差。14个子流域的健康状况差异并不显著,琉璃河、白河下段、汤河上游的健康状况相对较好,潮河中下段和小汤河的健康状况相对较差。流域内不合理的畜禽养殖、岸边带种植及民俗旅游是导致流域生态健康退化的主要原因,建议加强污染负荷排放的控制和监管涉水活动对水生生境的干扰以改善流域健康状况,并重点关注可指示水生态系统早期退化的生物指数,以实现可持续性和适应性的流域管理,保障密云水库的水生态安全。  相似文献   

16.
崔宁  于恩逸  李爽  唐明方  吴钢 《生态学报》2021,41(3):949-958
内蒙古高原湖泊流域是我国北方地区重要的涵养水源区域,发挥着防汛抗旱、气候调节、生物多样性维持等多种生态系统功能。近几十年来,全球气候变化加之人类活动加剧,导致内蒙古高原湖泊的数量和面积大幅减少,流域生态系统的损害日益明显,严重威胁到了周边地区的生态安全,保护与治理内蒙古高原湖泊流域已逐渐成为社会各界关注及迫切需要解决的问题。面向内蒙古高原湖泊流域保护和管理需求,以改善和提升流域生态环境质量和生态系统功能为目的,以内蒙古高原湖泊达里湖流域为研究对象,基于流域生态特性和主要生态环境问题,选取水土流失、土壤侵蚀及土地沙化敏感性3个指标评价了流域生态系统敏感性,从水源涵养、土壤保持和生境质量重要性3个方面评价了流域生态系统功能重要性,并在此基础上,通过GIS空间分析技术将流域分为极重要敏感区,一般重要敏感区和低重要敏感区。结合流域内达里诺尔国家级自然保护区的生态重要性与3个区域评价结果,从生态保护角度将流域分为禁止开发区、重点保护区、质量提升区与潜在威胁区4个区域,同时提出针对每个区域特点的保护与管理对策。研究结果对提高高原地区湖泊流域生态环境质量以及对流域实施科学有效的管理提供了科学依据,同时在促进区域乃至全球生态建设和可持续发展方面具有重要的理论与现实意义。  相似文献   

17.
The interactions between climate and land‐use change are dictating the distribution of flora and fauna and reshuffling biotic community composition around the world. Tropical mountains are particularly sensitive because they often have a high human population density, a long history of agriculture, range‐restricted species, and high‐beta diversity due to a steep elevation gradient. Here we evaluated the change in distribution of woody vegetation in the tropical Andes of South America for the period 2001–2014. For the analyses we created annual land‐cover/land‐use maps using MODIS satellite data at 250 m pixel resolution, calculated the cover of woody vegetation (trees and shrubs) in 9,274 hexagons of 115.47 km2, and then determined if there was a statistically significant (p < 0.05) 14 year linear trend (positive—forest gain, negative—forest loss) within each hexagon. Of the 1,308 hexagons with significant trends, 36.6% (n = 479) lost forests and 63.4% (n = 829) gained forests. We estimated an overall net gain of ~500,000 ha in woody vegetation. Forest loss dominated the 1,000–1,499 m elevation zone and forest gain dominated above 1,500 m. The most important transitions were forest loss at lower elevations for pastures and croplands, forest gain in abandoned pastures and cropland in mid‐elevation areas, and shrub encroachment into highland grasslands. Expert validation confirmed the observed trends, but some areas of apparent forest gain were associated with new shade coffee, pine, or eucalypt plantations. In addition, after controlling for elevation and country, forest gain was associated with a decline in the rural population. Although we document an overall gain in forest cover, the recent reversal of forest gains in Colombia demonstrates that these coupled natural‐human systems are highly dynamic and there is an urgent need of a regional real‐time land‐use, biodiversity, and ecosystem services monitoring network.  相似文献   

18.
There are concerns over the increasing concentrations of trace metals being found in the environment. Deltas are essentially integrators of watershed contamination as they are the repositories of sediment transported from and through the watershed. In order to assess changes in trace metal concentrations transported by the Mississippi River–Atchafalaya River systems, vibracores were collected from three coastal freshwater marsh sites under the influence of the Atchafalaya River and emerging Wax Lake Delta (WLD). The cores extended to a depth of 4 m which included deposits of an earlier Mississippi River Delta lobe. C-14 dating showed an age at the lower depth corresponding to approximately 3500 years ago. Vertical profile distribution of metals and metalloids were measured and comparisons between older deposits and concentrations in recent deposits were made. Concentrations of As, Cr, Cu, Ni, Zn, Mo, V, Co, and Hg metals were measured in the profiles along with Fe, Mn, and Al. There was no significant increase in heavy metals or metalloids in recent years as compared to more than 3000-year-old sediment associated with an earlier Mississippi River Delta lobe. Results show that sediment diversion through the Wax Lake Outlet did not increase concentrations of these metals in surface marsh soils. The metal concentrations in the marsh profile were compared to ERL (effects range low) and ERM (effects range medium) values to allow an ecotoxicological assessment. Arsenic was below the ERM values but was greater than the ERL which indicate a potential toxicity under certain conditions. All other metal/metalloids measured were below ERL limits. This study suggests that planned Mississippi River sediment diversions designed to slow the rate of coastal land loss are not likely to lead to trace metals contamination.  相似文献   

19.
20.
Threats to riverine landscapes are often the result of system‐wide river management policy, located far from where the threats appear, or both. As a result, the rationale for land protection to achieve floodplain conservation and restoration has shifted to require that lands must also have multiple and systemic threat abatement benefits. The Mississippi River Flood of 2011 highlighted the need for increased floodplain complexes along the Mississippi River to provide both systemic threat abatement and conservation benefits. We used spatial analysis, landowner outreach, and market assessment to examine ways to enhance land protection in the Atchafalaya River Basin Floodway, the largest river basin swamp North America and the site of two employed floodway locations during the 2011 flood. We identified six Priority Conservation Areas (77,084 ha) in the floodway that are largely privately owned (mean 78.2 ± 6.4%), with forest dominated by Taxodium distichum (baldcypress) and hydrologic and water quality characteristics considered most suitable for baldcypress regeneration (31.2 ± 2.4% and 10.2 ± 3.0% of area, respectively). Landowners expressed high (80%) interest in land protection programs and found the range of property values derived from market analyzes (minimal protection—$346 USD/ha; additional protections—up to $2,223 USD/ha) to be reasonable. We seek to: (1) enhance current land protection in the Atchafalaya River Basin and (2) provide a model for using land protection to increase the number of floodplains for both systemic threat abatement and conservation benefits.  相似文献   

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